lowfield_mri_programs/picoscope-main/pugixml.cpp

/**
 * pugixml parser - version 1.14
 * --------------------------------------------------------
 * Copyright (C) 2006-2023, by Arseny Kapoulkine (arseny.kapoulkine@gmail.com)
 * Report bugs and download new versions at https://pugixml.org/
 *
 * This library is distributed under the MIT License. See notice at the end
 * of this file.
 *
 * This work is based on the pugxml parser, which is:
 * Copyright (C) 2003, by Kristen Wegner (kristen@tima.net)
 */

#ifndef SOURCE_PUGIXML_CPP
#define SOURCE_PUGIXML_CPP

#include "pugixml.hpp"

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <limits.h>

#ifdef PUGIXML_WCHAR_MODE
#	include <wchar.h>
#endif

#ifndef PUGIXML_NO_XPATH
#	include <math.h>
#	include <float.h>
#endif

#ifndef PUGIXML_NO_STL
#	include <istream>
#	include <ostream>
#	include <string>
#endif

// For placement new
#include <new>

// For load_file
#if defined(__linux__) || defined(__APPLE__)
#include <sys/stat.h>
#endif

#ifdef _MSC_VER
#	pragma warning(push)
#	pragma warning(disable: 4127) // conditional expression is constant
#	pragma warning(disable: 4324) // structure was padded due to __declspec(align())
#	pragma warning(disable: 4702) // unreachable code
#	pragma warning(disable: 4996) // this function or variable may be unsafe
#endif

#if defined(_MSC_VER) && defined(__c2__)
#	pragma clang diagnostic push
#	pragma clang diagnostic ignored "-Wdeprecated" // this function or variable may be unsafe
#endif

#ifdef __INTEL_COMPILER
#	pragma warning(disable: 177) // function was declared but never referenced
#	pragma warning(disable: 279) // controlling expression is constant
#	pragma warning(disable: 1478 1786) // function was declared "deprecated"
#	pragma warning(disable: 1684) // conversion from pointer to same-sized integral type
#endif

#if defined(__BORLANDC__) && defined(PUGIXML_HEADER_ONLY)
#	pragma warn -8080 // symbol is declared but never used; disabling this inside push/pop bracket does not make the warning go away
#endif

#ifdef __BORLANDC__
#	pragma option push
#	pragma warn -8008 // condition is always false
#	pragma warn -8066 // unreachable code
#endif

#ifdef __SNC__
// Using diag_push/diag_pop does not disable the warnings inside templates due to a compiler bug
#	pragma diag_suppress=178 // function was declared but never referenced
#	pragma diag_suppress=237 // controlling expression is constant
#endif

#ifdef __TI_COMPILER_VERSION__
#	pragma diag_suppress 179 // function was declared but never referenced
#endif

// Inlining controls
#if defined(_MSC_VER) && _MSC_VER >= 1300
#	define PUGI_IMPL_NO_INLINE __declspec(noinline)
#elif defined(__GNUC__)
#	define PUGI_IMPL_NO_INLINE __attribute__((noinline))
#else
#	define PUGI_IMPL_NO_INLINE
#endif

// Branch weight controls
#if defined(__GNUC__) && !defined(__c2__)
#	define PUGI_IMPL_UNLIKELY(cond) __builtin_expect(cond, 0)
#else
#	define PUGI_IMPL_UNLIKELY(cond) (cond)
#endif

// Simple static assertion
#define PUGI_IMPL_STATIC_ASSERT(cond) { static const char condition_failed[(cond) ? 1 : -1] = {0}; (void)condition_failed[0]; }

// Digital Mars C++ bug workaround for passing char loaded from memory via stack
#ifdef __DMC__
#	define PUGI_IMPL_DMC_VOLATILE volatile
#else
#	define PUGI_IMPL_DMC_VOLATILE
#endif

// Integer sanitizer workaround; we only apply this for clang since gcc8 has no_sanitize but not unsigned-integer-overflow and produces "attribute directive ignored" warnings
#if defined(__clang__) && defined(__has_attribute)
#	if __has_attribute(no_sanitize)
#		define PUGI_IMPL_UNSIGNED_OVERFLOW __attribute__((no_sanitize("unsigned-integer-overflow")))
#	else
#		define PUGI_IMPL_UNSIGNED_OVERFLOW
#	endif
#else
#	define PUGI_IMPL_UNSIGNED_OVERFLOW
#endif

// Borland C++ bug workaround for not defining ::memcpy depending on header include order (can't always use std::memcpy because some compilers don't have it at all)
#if defined(__BORLANDC__) && !defined(__MEM_H_USING_LIST)
using std::memcpy;
using std::memmove;
using std::memset;
#endif

// Old versions of GCC do not define ::malloc and ::free depending on header include order
#if defined(__GNUC__) && (__GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 4))
using std::malloc;
using std::free;
#endif

// Some MinGW/GCC versions have headers that erroneously omit LLONG_MIN/LLONG_MAX/ULLONG_MAX definitions from limits.h in some configurations
#if defined(PUGIXML_HAS_LONG_LONG) && defined(__GNUC__) && !defined(LLONG_MAX) && !defined(LLONG_MIN) && !defined(ULLONG_MAX)
#	define LLONG_MIN (-LLONG_MAX - 1LL)
#	define LLONG_MAX __LONG_LONG_MAX__
#	define ULLONG_MAX (LLONG_MAX * 2ULL + 1ULL)
#endif

// In some environments MSVC is a compiler but the CRT lacks certain MSVC-specific features
#if defined(_MSC_VER) && !defined(__S3E__) && !defined(_WIN32_WCE)
#	define PUGI_IMPL_MSVC_CRT_VERSION _MSC_VER
#elif defined(_WIN32_WCE)
#	define PUGI_IMPL_MSVC_CRT_VERSION 1310 // MSVC7.1
#endif

// Not all platforms have snprintf; we define a wrapper that uses snprintf if possible. This only works with buffers with a known size.
#if __cplusplus >= 201103
#	define PUGI_IMPL_SNPRINTF(buf, ...) snprintf(buf, sizeof(buf), __VA_ARGS__)
#elif defined(PUGI_IMPL_MSVC_CRT_VERSION) && PUGI_IMPL_MSVC_CRT_VERSION >= 1400
#	define PUGI_IMPL_SNPRINTF(buf, ...) _snprintf_s(buf, _countof(buf), _TRUNCATE, __VA_ARGS__)
#elif defined(__APPLE__) && __clang_major__ >= 14 // Xcode 14 marks sprintf as deprecated while still using C++98 by default
#	define PUGI_IMPL_SNPRINTF(buf, fmt, arg1, arg2) snprintf(buf, sizeof(buf), fmt, arg1, arg2)
#else
#	define PUGI_IMPL_SNPRINTF sprintf
#endif

// We put implementation details into an anonymous namespace in source mode, but have to keep it in non-anonymous namespace in header-only mode to prevent binary bloat.
#ifdef PUGIXML_HEADER_ONLY
#	define PUGI_IMPL_NS_BEGIN namespace pugi { namespace impl {
#	define PUGI_IMPL_NS_END } }
#	define PUGI_IMPL_FN inline
#	define PUGI_IMPL_FN_NO_INLINE inline
#else
#	if defined(_MSC_VER) && _MSC_VER < 1300 // MSVC6 seems to have an amusing bug with anonymous namespaces inside namespaces
#		define PUGI_IMPL_NS_BEGIN namespace pugi { namespace impl {
#		define PUGI_IMPL_NS_END } }
#	else
#		define PUGI_IMPL_NS_BEGIN namespace pugi { namespace impl { namespace {
#		define PUGI_IMPL_NS_END } } }
#	endif
#	define PUGI_IMPL_FN
#	define PUGI_IMPL_FN_NO_INLINE PUGI_IMPL_NO_INLINE
#endif

// uintptr_t
#if (defined(_MSC_VER) && _MSC_VER < 1600) || (defined(__BORLANDC__) && __BORLANDC__ < 0x561)
namespace pugi
{
#	ifndef _UINTPTR_T_DEFINED
	typedef size_t uintptr_t;
#	endif

	typedef unsigned __int8 uint8_t;
	typedef unsigned __int16 uint16_t;
	typedef unsigned __int32 uint32_t;
}
#else
#	include <stdint.h>
#endif

// Memory allocation
PUGI_IMPL_NS_BEGIN
	PUGI_IMPL_FN void* default_allocate(size_t size)
	{
		return malloc(size);
	}

	PUGI_IMPL_FN void default_deallocate(void* ptr)
	{
		free(ptr);
	}

	template <typename T>
	struct xml_memory_management_function_storage
	{
		static allocation_function allocate;
		static deallocation_function deallocate;
	};

	// Global allocation functions are stored in class statics so that in header mode linker deduplicates them
	// Without a template<> we'll get multiple definitions of the same static
	template <typename T> allocation_function xml_memory_management_function_storage<T>::allocate = default_allocate;
	template <typename T> deallocation_function xml_memory_management_function_storage<T>::deallocate = default_deallocate;

	typedef xml_memory_management_function_storage<int> xml_memory;
PUGI_IMPL_NS_END

// String utilities
PUGI_IMPL_NS_BEGIN
	// Get string length
	PUGI_IMPL_FN size_t strlength(const char_t* s)
	{
		assert(s);

	#ifdef PUGIXML_WCHAR_MODE
		return wcslen(s);
	#else
		return strlen(s);
	#endif
	}

	// Compare two strings
	PUGI_IMPL_FN bool strequal(const char_t* src, const char_t* dst)
	{
		assert(src && dst);

	#ifdef PUGIXML_WCHAR_MODE
		return wcscmp(src, dst) == 0;
	#else
		return strcmp(src, dst) == 0;
	#endif
	}

	// Compare lhs with [rhs_begin, rhs_end)
	PUGI_IMPL_FN bool strequalrange(const char_t* lhs, const char_t* rhs, size_t count)
	{
		for (size_t i = 0; i < count; ++i)
			if (lhs[i] != rhs[i])
				return false;

		return lhs[count] == 0;
	}

	// Get length of wide string, even if CRT lacks wide character support
	PUGI_IMPL_FN size_t strlength_wide(const wchar_t* s)
	{
		assert(s);

	#ifdef PUGIXML_WCHAR_MODE
		return wcslen(s);
	#else
		const wchar_t* end = s;
		while (*end) end++;
		return static_cast<size_t>(end - s);
	#endif
	}
PUGI_IMPL_NS_END

// auto_ptr-like object for exception recovery
PUGI_IMPL_NS_BEGIN
	template <typename T> struct auto_deleter
	{
		typedef void (*D)(T*);

		T* data;
		D deleter;

		auto_deleter(T* data_, D deleter_): data(data_), deleter(deleter_)
		{
		}

		~auto_deleter()
		{
			if (data) deleter(data);
		}

		T* release()
		{
			T* result = data;
			data = 0;
			return result;
		}
	};
PUGI_IMPL_NS_END

#ifdef PUGIXML_COMPACT
PUGI_IMPL_NS_BEGIN
	class compact_hash_table
	{
	public:
		compact_hash_table(): _items(0), _capacity(0), _count(0)
		{
		}

		void clear()
		{
			if (_items)
			{
				xml_memory::deallocate(_items);
				_items = 0;
				_capacity = 0;
				_count = 0;
			}
		}

		void* find(const void* key)
		{
			if (_capacity == 0) return 0;

			item_t* item = get_item(key);
			assert(item);
			assert(item->key == key || (item->key == 0 && item->value == 0));

			return item->value;
		}

		void insert(const void* key, void* value)
		{
			assert(_capacity != 0 && _count < _capacity - _capacity / 4);

			item_t* item = get_item(key);
			assert(item);

			if (item->key == 0)
			{
				_count++;
				item->key = key;
			}

			item->value = value;
		}

		bool reserve(size_t extra = 16)
		{
			if (_count + extra >= _capacity - _capacity / 4)
				return rehash(_count + extra);

			return true;
		}

	private:
		struct item_t
		{
			const void* key;
			void* value;
		};

		item_t* _items;
		size_t _capacity;

		size_t _count;

		bool rehash(size_t count);

		item_t* get_item(const void* key)
		{
			assert(key);
			assert(_capacity > 0);

			size_t hashmod = _capacity - 1;
			size_t bucket = hash(key) & hashmod;

			for (size_t probe = 0; probe <= hashmod; ++probe)
			{
				item_t& probe_item = _items[bucket];

				if (probe_item.key == key || probe_item.key == 0)
					return &probe_item;

				// hash collision, quadratic probing
				bucket = (bucket + probe + 1) & hashmod;
			}

			assert(false && "Hash table is full"); // unreachable
			return 0;
		}

		static PUGI_IMPL_UNSIGNED_OVERFLOW unsigned int hash(const void* key)
		{
			unsigned int h = static_cast<unsigned int>(reinterpret_cast<uintptr_t>(key) & 0xffffffff);

			// MurmurHash3 32-bit finalizer
			h ^= h >> 16;
			h *= 0x85ebca6bu;
			h ^= h >> 13;
			h *= 0xc2b2ae35u;
			h ^= h >> 16;

			return h;
		}
	};

	PUGI_IMPL_FN_NO_INLINE bool compact_hash_table::rehash(size_t count)
	{
		size_t capacity = 32;
		while (count >= capacity - capacity / 4)
			capacity *= 2;

		compact_hash_table rt;
		rt._capacity = capacity;
		rt._items = static_cast<item_t*>(xml_memory::allocate(sizeof(item_t) * capacity));

		if (!rt._items)
			return false;

		memset(rt._items, 0, sizeof(item_t) * capacity);

		for (size_t i = 0; i < _capacity; ++i)
			if (_items[i].key)
				rt.insert(_items[i].key, _items[i].value);

		if (_items)
			xml_memory::deallocate(_items);

		_capacity = capacity;
		_items = rt._items;

		assert(_count == rt._count);

		return true;
	}

PUGI_IMPL_NS_END
#endif

PUGI_IMPL_NS_BEGIN
#ifdef PUGIXML_COMPACT
	static const uintptr_t xml_memory_block_alignment = 4;
#else
	static const uintptr_t xml_memory_block_alignment = sizeof(void*);
#endif

	// extra metadata bits
	static const uintptr_t xml_memory_page_contents_shared_mask = 64;
	static const uintptr_t xml_memory_page_name_allocated_mask = 32;
	static const uintptr_t xml_memory_page_value_allocated_mask = 16;
	static const uintptr_t xml_memory_page_type_mask = 15;

	// combined masks for string uniqueness
	static const uintptr_t xml_memory_page_name_allocated_or_shared_mask = xml_memory_page_name_allocated_mask | xml_memory_page_contents_shared_mask;
	static const uintptr_t xml_memory_page_value_allocated_or_shared_mask = xml_memory_page_value_allocated_mask | xml_memory_page_contents_shared_mask;

#ifdef PUGIXML_COMPACT
	#define PUGI_IMPL_GETHEADER_IMPL(object, page, flags) // unused
	#define PUGI_IMPL_GETPAGE_IMPL(header) (header).get_page()
#else
	#define PUGI_IMPL_GETHEADER_IMPL(object, page, flags) (((reinterpret_cast<char*>(object) - reinterpret_cast<char*>(page)) << 8) | (flags))
	// this macro casts pointers through void* to avoid 'cast increases required alignment of target type' warnings
	#define PUGI_IMPL_GETPAGE_IMPL(header) static_cast<impl::xml_memory_page*>(const_cast<void*>(static_cast<const void*>(reinterpret_cast<const char*>(&header) - (header >> 8))))
#endif

	#define PUGI_IMPL_GETPAGE(n) PUGI_IMPL_GETPAGE_IMPL((n)->header)
	#define PUGI_IMPL_NODETYPE(n) static_cast<xml_node_type>((n)->header & impl::xml_memory_page_type_mask)

	struct xml_allocator;

	struct xml_memory_page
	{
		static xml_memory_page* construct(void* memory)
		{
			xml_memory_page* result = static_cast<xml_memory_page*>(memory);

			result->allocator = 0;
			result->prev = 0;
			result->next = 0;
			result->busy_size = 0;
			result->freed_size = 0;

		#ifdef PUGIXML_COMPACT
			result->compact_string_base = 0;
			result->compact_shared_parent = 0;
			result->compact_page_marker = 0;
		#endif

			return result;
		}

		xml_allocator* allocator;

		xml_memory_page* prev;
		xml_memory_page* next;

		size_t busy_size;
		size_t freed_size;

	#ifdef PUGIXML_COMPACT
		char_t* compact_string_base;
		void* compact_shared_parent;
		uint32_t* compact_page_marker;
	#endif
	};

	static const size_t xml_memory_page_size =
	#ifdef PUGIXML_MEMORY_PAGE_SIZE
		(PUGIXML_MEMORY_PAGE_SIZE)
	#else
		32768
	#endif
		- sizeof(xml_memory_page);

	struct xml_memory_string_header
	{
		uint16_t page_offset; // offset from page->data
		uint16_t full_size; // 0 if string occupies whole page
	};

	struct xml_allocator
	{
		xml_allocator(xml_memory_page* root): _root(root), _busy_size(root->busy_size)
		{
		#ifdef PUGIXML_COMPACT
			_hash = 0;
		#endif
		}

		xml_memory_page* allocate_page(size_t data_size)
		{
			size_t size = sizeof(xml_memory_page) + data_size;

			// allocate block with some alignment, leaving memory for worst-case padding
			void* memory = xml_memory::allocate(size);
			if (!memory) return 0;

			// prepare page structure
			xml_memory_page* page = xml_memory_page::construct(memory);
			assert(page);

			assert(this == _root->allocator);
			page->allocator = this;

			return page;
		}

		static void deallocate_page(xml_memory_page* page)
		{
			xml_memory::deallocate(page);
		}

		void* allocate_memory_oob(size_t size, xml_memory_page*& out_page);

		void* allocate_memory(size_t size, xml_memory_page*& out_page)
		{
			if (PUGI_IMPL_UNLIKELY(_busy_size + size > xml_memory_page_size))
				return allocate_memory_oob(size, out_page);

			void* buf = reinterpret_cast<char*>(_root) + sizeof(xml_memory_page) + _busy_size;

			_busy_size += size;

			out_page = _root;

			return buf;
		}

	#ifdef PUGIXML_COMPACT
		void* allocate_object(size_t size, xml_memory_page*& out_page)
		{
			void* result = allocate_memory(size + sizeof(uint32_t), out_page);
			if (!result) return 0;

			// adjust for marker
			ptrdiff_t offset = static_cast<char*>(result) - reinterpret_cast<char*>(out_page->compact_page_marker);

			if (PUGI_IMPL_UNLIKELY(static_cast<uintptr_t>(offset) >= 256 * xml_memory_block_alignment))
			{
				// insert new marker
				uint32_t* marker = static_cast<uint32_t*>(result);

				*marker = static_cast<uint32_t>(reinterpret_cast<char*>(marker) - reinterpret_cast<char*>(out_page));
				out_page->compact_page_marker = marker;

				// since we don't reuse the page space until we reallocate it, we can just pretend that we freed the marker block
				// this will make sure deallocate_memory correctly tracks the size
				out_page->freed_size += sizeof(uint32_t);

				return marker + 1;
			}
			else
			{
				// roll back uint32_t part
				_busy_size -= sizeof(uint32_t);

				return result;
			}
		}
	#else
		void* allocate_object(size_t size, xml_memory_page*& out_page)
		{
			return allocate_memory(size, out_page);
		}
	#endif

		void deallocate_memory(void* ptr, size_t size, xml_memory_page* page)
		{
			if (page == _root) page->busy_size = _busy_size;

			assert(ptr >= reinterpret_cast<char*>(page) + sizeof(xml_memory_page) && ptr < reinterpret_cast<char*>(page) + sizeof(xml_memory_page) + page->busy_size);
			(void)!ptr;

			page->freed_size += size;
			assert(page->freed_size <= page->busy_size);

			if (page->freed_size == page->busy_size)
			{
				if (page->next == 0)
				{
					assert(_root == page);

					// top page freed, just reset sizes
					page->busy_size = 0;
					page->freed_size = 0;

				#ifdef PUGIXML_COMPACT
					// reset compact state to maximize efficiency
					page->compact_string_base = 0;
					page->compact_shared_parent = 0;
					page->compact_page_marker = 0;
				#endif

					_busy_size = 0;
				}
				else
				{
					assert(_root != page);
					assert(page->prev);

					// remove from the list
					page->prev->next = page->next;
					page->next->prev = page->prev;

					// deallocate
					deallocate_page(page);
				}
			}
		}

		char_t* allocate_string(size_t length)
		{
			static const size_t max_encoded_offset = (1 << 16) * xml_memory_block_alignment;

			PUGI_IMPL_STATIC_ASSERT(xml_memory_page_size <= max_encoded_offset);

			// allocate memory for string and header block
			size_t size = sizeof(xml_memory_string_header) + length * sizeof(char_t);

			// round size up to block alignment boundary
			size_t full_size = (size + (xml_memory_block_alignment - 1)) & ~(xml_memory_block_alignment - 1);

			xml_memory_page* page;
			xml_memory_string_header* header = static_cast<xml_memory_string_header*>(allocate_memory(full_size, page));

			if (!header) return 0;

			// setup header
			ptrdiff_t page_offset = reinterpret_cast<char*>(header) - reinterpret_cast<char*>(page) - sizeof(xml_memory_page);

			assert(page_offset % xml_memory_block_alignment == 0);
			assert(page_offset >= 0 && static_cast<size_t>(page_offset) < max_encoded_offset);
			header->page_offset = static_cast<uint16_t>(static_cast<size_t>(page_offset) / xml_memory_block_alignment);

			// full_size == 0 for large strings that occupy the whole page
			assert(full_size % xml_memory_block_alignment == 0);
			assert(full_size < max_encoded_offset || (page->busy_size == full_size && page_offset == 0));
			header->full_size = static_cast<uint16_t>(full_size < max_encoded_offset ? full_size / xml_memory_block_alignment : 0);

			// round-trip through void* to avoid 'cast increases required alignment of target type' warning
			// header is guaranteed a pointer-sized alignment, which should be enough for char_t
			return static_cast<char_t*>(static_cast<void*>(header + 1));
		}

		void deallocate_string(char_t* string)
		{
			// this function casts pointers through void* to avoid 'cast increases required alignment of target type' warnings
			// we're guaranteed the proper (pointer-sized) alignment on the input string if it was allocated via allocate_string

			// get header
			xml_memory_string_header* header = static_cast<xml_memory_string_header*>(static_cast<void*>(string)) - 1;
			assert(header);

			// deallocate
			size_t page_offset = sizeof(xml_memory_page) + header->page_offset * xml_memory_block_alignment;
			xml_memory_page* page = reinterpret_cast<xml_memory_page*>(static_cast<void*>(reinterpret_cast<char*>(header) - page_offset));

			// if full_size == 0 then this string occupies the whole page
			size_t full_size = header->full_size == 0 ? page->busy_size : header->full_size * xml_memory_block_alignment;

			deallocate_memory(header, full_size, page);
		}

		bool reserve()
		{
		#ifdef PUGIXML_COMPACT
			return _hash->reserve();
		#else
			return true;
		#endif
		}

		xml_memory_page* _root;
		size_t _busy_size;

	#ifdef PUGIXML_COMPACT
		compact_hash_table* _hash;
	#endif
	};

	PUGI_IMPL_FN_NO_INLINE void* xml_allocator::allocate_memory_oob(size_t size, xml_memory_page*& out_page)
	{
		const size_t large_allocation_threshold = xml_memory_page_size / 4;

		xml_memory_page* page = allocate_page(size <= large_allocation_threshold ? xml_memory_page_size : size);
		out_page = page;

		if (!page) return 0;

		if (size <= large_allocation_threshold)
		{
			_root->busy_size = _busy_size;

			// insert page at the end of linked list
			page->prev = _root;
			_root->next = page;
			_root = page;

			_busy_size = size;
		}
		else
		{
			// insert page before the end of linked list, so that it is deleted as soon as possible
			// the last page is not deleted even if it's empty (see deallocate_memory)
			assert(_root->prev);

			page->prev = _root->prev;
			page->next = _root;

			_root->prev->next = page;
			_root->prev = page;

			page->busy_size = size;
		}

		return reinterpret_cast<char*>(page) + sizeof(xml_memory_page);
	}
PUGI_IMPL_NS_END

#ifdef PUGIXML_COMPACT
PUGI_IMPL_NS_BEGIN
	static const uintptr_t compact_alignment_log2 = 2;
	static const uintptr_t compact_alignment = 1 << compact_alignment_log2;

	class compact_header
	{
	public:
		compact_header(xml_memory_page* page, unsigned int flags)
		{
			PUGI_IMPL_STATIC_ASSERT(xml_memory_block_alignment == compact_alignment);

			ptrdiff_t offset = (reinterpret_cast<char*>(this) - reinterpret_cast<char*>(page->compact_page_marker));
			assert(offset % compact_alignment == 0 && static_cast<uintptr_t>(offset) < 256 * compact_alignment);

			_page = static_cast<unsigned char>(offset >> compact_alignment_log2);
			_flags = static_cast<unsigned char>(flags);
		}

		void operator&=(uintptr_t mod)
		{
			_flags &= static_cast<unsigned char>(mod);
		}

		void operator|=(uintptr_t mod)
		{
			_flags |= static_cast<unsigned char>(mod);
		}

		uintptr_t operator&(uintptr_t mod) const
		{
			return _flags & mod;
		}

		xml_memory_page* get_page() const
		{
			// round-trip through void* to silence 'cast increases required alignment of target type' warnings
			const char* page_marker = reinterpret_cast<const char*>(this) - (_page << compact_alignment_log2);
			const char* page = page_marker - *reinterpret_cast<const uint32_t*>(static_cast<const void*>(page_marker));

			return const_cast<xml_memory_page*>(reinterpret_cast<const xml_memory_page*>(static_cast<const void*>(page)));
		}

	private:
		unsigned char _page;
		unsigned char _flags;
	};

	PUGI_IMPL_FN xml_memory_page* compact_get_page(const void* object, int header_offset)
	{
		const compact_header* header = reinterpret_cast<const compact_header*>(static_cast<const char*>(object) - header_offset);

		return header->get_page();
	}

	template <int header_offset, typename T> PUGI_IMPL_FN_NO_INLINE T* compact_get_value(const void* object)
	{
		return static_cast<T*>(compact_get_page(object, header_offset)->allocator->_hash->find(object));
	}

	template <int header_offset, typename T> PUGI_IMPL_FN_NO_INLINE void compact_set_value(const void* object, T* value)
	{
		compact_get_page(object, header_offset)->allocator->_hash->insert(object, value);
	}

	template <typename T, int header_offset, int start = -126> class compact_pointer
	{
	public:
		compact_pointer(): _data(0)
		{
		}

		void operator=(const compact_pointer& rhs)
		{
			*this = rhs + 0;
		}

		void operator=(T* value)
		{
			if (value)
			{
				// value is guaranteed to be compact-aligned; 'this' is not
				// our decoding is based on 'this' aligned to compact alignment downwards (see operator T*)
				// so for negative offsets (e.g. -3) we need to adjust the diff by compact_alignment - 1 to
				// compensate for arithmetic shift rounding for negative values
				ptrdiff_t diff = reinterpret_cast<char*>(value) - reinterpret_cast<char*>(this);
				ptrdiff_t offset = ((diff + int(compact_alignment - 1)) >> compact_alignment_log2) - start;

				if (static_cast<uintptr_t>(offset) <= 253)
					_data = static_cast<unsigned char>(offset + 1);
				else
				{
					compact_set_value<header_offset>(this, value);

					_data = 255;
				}
			}
			else
				_data = 0;
		}

		operator T*() const
		{
			if (_data)
			{
				if (_data < 255)
				{
					uintptr_t base = reinterpret_cast<uintptr_t>(this) & ~(compact_alignment - 1);

					return reinterpret_cast<T*>(base + (_data - 1 + start) * compact_alignment);
				}
				else
					return compact_get_value<header_offset, T>(this);
			}
			else
				return 0;
		}

		T* operator->() const
		{
			return *this;
		}

	private:
		unsigned char _data;
	};

	template <typename T, int header_offset> class compact_pointer_parent
	{
	public:
		compact_pointer_parent(): _data(0)
		{
		}

		void operator=(const compact_pointer_parent& rhs)
		{
			*this = rhs + 0;
		}

		void operator=(T* value)
		{
			if (value)
			{
				// value is guaranteed to be compact-aligned; 'this' is not
				// our decoding is based on 'this' aligned to compact alignment downwards (see operator T*)
				// so for negative offsets (e.g. -3) we need to adjust the diff by compact_alignment - 1 to
				// compensate for arithmetic shift behavior for negative values
				ptrdiff_t diff = reinterpret_cast<char*>(value) - reinterpret_cast<char*>(this);
				ptrdiff_t offset = ((diff + int(compact_alignment - 1)) >> compact_alignment_log2) + 65533;

				if (static_cast<uintptr_t>(offset) <= 65533)
				{
					_data = static_cast<unsigned short>(offset + 1);
				}
				else
				{
					xml_memory_page* page = compact_get_page(this, header_offset);

					if (PUGI_IMPL_UNLIKELY(page->compact_shared_parent == 0))
						page->compact_shared_parent = value;

					if (page->compact_shared_parent == value)
					{
						_data = 65534;
					}
					else
					{
						compact_set_value<header_offset>(this, value);

						_data = 65535;
					}
				}
			}
			else
			{
				_data = 0;
			}
		}

		operator T*() const
		{
			if (_data)
			{
				if (_data < 65534)
				{
					uintptr_t base = reinterpret_cast<uintptr_t>(this) & ~(compact_alignment - 1);

					return reinterpret_cast<T*>(base + (_data - 1 - 65533) * compact_alignment);
				}
				else if (_data == 65534)
					return static_cast<T*>(compact_get_page(this, header_offset)->compact_shared_parent);
				else
					return compact_get_value<header_offset, T>(this);
			}
			else
				return 0;
		}

		T* operator->() const
		{
			return *this;
		}

	private:
		uint16_t _data;
	};

	template <int header_offset, int base_offset> class compact_string
	{
	public:
		compact_string(): _data(0)
		{
		}

		void operator=(const compact_string& rhs)
		{
			*this = rhs + 0;
		}

		void operator=(char_t* value)
		{
			if (value)
			{
				xml_memory_page* page = compact_get_page(this, header_offset);

				if (PUGI_IMPL_UNLIKELY(page->compact_string_base == 0))
					page->compact_string_base = value;

				ptrdiff_t offset = value - page->compact_string_base;

				if (static_cast<uintptr_t>(offset) < (65535 << 7))
				{
					// round-trip through void* to silence 'cast increases required alignment of target type' warnings
					uint16_t* base = reinterpret_cast<uint16_t*>(static_cast<void*>(reinterpret_cast<char*>(this) - base_offset));

					if (*base == 0)
					{
						*base = static_cast<uint16_t>((offset >> 7) + 1);
						_data = static_cast<unsigned char>((offset & 127) + 1);
					}
					else
					{
						ptrdiff_t remainder = offset - ((*base - 1) << 7);

						if (static_cast<uintptr_t>(remainder) <= 253)
						{
							_data = static_cast<unsigned char>(remainder + 1);
						}
						else
						{
							compact_set_value<header_offset>(this, value);

							_data = 255;
						}
					}
				}
				else
				{
					compact_set_value<header_offset>(this, value);

					_data = 255;
				}
			}
			else
			{
				_data = 0;
			}
		}

		operator char_t*() const
		{
			if (_data)
			{
				if (_data < 255)
				{
					xml_memory_page* page = compact_get_page(this, header_offset);

					// round-trip through void* to silence 'cast increases required alignment of target type' warnings
					const uint16_t* base = reinterpret_cast<const uint16_t*>(static_cast<const void*>(reinterpret_cast<const char*>(this) - base_offset));
					assert(*base);

					ptrdiff_t offset = ((*base - 1) << 7) + (_data - 1);

					return page->compact_string_base + offset;
				}
				else
				{
					return compact_get_value<header_offset, char_t>(this);
				}
			}
			else
				return 0;
		}

	private:
		unsigned char _data;
	};
PUGI_IMPL_NS_END
#endif

#ifdef PUGIXML_COMPACT
namespace pugi
{
	struct xml_attribute_struct
	{
		xml_attribute_struct(impl::xml_memory_page* page): header(page, 0), namevalue_base(0)
		{
			PUGI_IMPL_STATIC_ASSERT(sizeof(xml_attribute_struct) == 8);
		}

		impl::compact_header header;

		uint16_t namevalue_base;

		impl::compact_string<4, 2> name;
		impl::compact_string<5, 3> value;

		impl::compact_pointer<xml_attribute_struct, 6> prev_attribute_c;
		impl::compact_pointer<xml_attribute_struct, 7, 0> next_attribute;
	};

	struct xml_node_struct
	{
		xml_node_struct(impl::xml_memory_page* page, xml_node_type type): header(page, type), namevalue_base(0)
		{
			PUGI_IMPL_STATIC_ASSERT(sizeof(xml_node_struct) == 12);
		}

		impl::compact_header header;

		uint16_t namevalue_base;

		impl::compact_string<4, 2> name;
		impl::compact_string<5, 3> value;

		impl::compact_pointer_parent<xml_node_struct, 6> parent;

		impl::compact_pointer<xml_node_struct, 8, 0> first_child;

		impl::compact_pointer<xml_node_struct,  9>    prev_sibling_c;
		impl::compact_pointer<xml_node_struct, 10, 0> next_sibling;

		impl::compact_pointer<xml_attribute_struct, 11, 0> first_attribute;
	};
}
#else
namespace pugi
{
	struct xml_attribute_struct
	{
		xml_attribute_struct(impl::xml_memory_page* page): name(0), value(0), prev_attribute_c(0), next_attribute(0)
		{
			header = PUGI_IMPL_GETHEADER_IMPL(this, page, 0);
		}

		uintptr_t header;

		char_t*	name;
		char_t*	value;

		xml_attribute_struct* prev_attribute_c;
		xml_attribute_struct* next_attribute;
	};

	struct xml_node_struct
	{
		xml_node_struct(impl::xml_memory_page* page, xml_node_type type): name(0), value(0), parent(0), first_child(0), prev_sibling_c(0), next_sibling(0), first_attribute(0)
		{
			header = PUGI_IMPL_GETHEADER_IMPL(this, page, type);
		}

		uintptr_t header;

		char_t* name;
		char_t* value;

		xml_node_struct* parent;

		xml_node_struct* first_child;

		xml_node_struct* prev_sibling_c;
		xml_node_struct* next_sibling;

		xml_attribute_struct* first_attribute;
	};
}
#endif

PUGI_IMPL_NS_BEGIN
	struct xml_extra_buffer
	{
		char_t* buffer;
		xml_extra_buffer* next;
	};

	struct xml_document_struct: public xml_node_struct, public xml_allocator
	{
		xml_document_struct(xml_memory_page* page): xml_node_struct(page, node_document), xml_allocator(page), buffer(0), extra_buffers(0)
		{
		}

		const char_t* buffer;

		xml_extra_buffer* extra_buffers;

	#ifdef PUGIXML_COMPACT
		compact_hash_table hash;
	#endif
	};

	template <typename Object> inline xml_allocator& get_allocator(const Object* object)
	{
		assert(object);

		return *PUGI_IMPL_GETPAGE(object)->allocator;
	}

	template <typename Object> inline xml_document_struct& get_document(const Object* object)
	{
		assert(object);

		return *static_cast<xml_document_struct*>(PUGI_IMPL_GETPAGE(object)->allocator);
	}
PUGI_IMPL_NS_END

// Low-level DOM operations
PUGI_IMPL_NS_BEGIN
	inline xml_attribute_struct* allocate_attribute(xml_allocator& alloc)
	{
		xml_memory_page* page;
		void* memory = alloc.allocate_object(sizeof(xml_attribute_struct), page);
		if (!memory) return 0;

		return new (memory) xml_attribute_struct(page);
	}

	inline xml_node_struct* allocate_node(xml_allocator& alloc, xml_node_type type)
	{
		xml_memory_page* page;
		void* memory = alloc.allocate_object(sizeof(xml_node_struct), page);
		if (!memory) return 0;

		return new (memory) xml_node_struct(page, type);
	}

	inline void destroy_attribute(xml_attribute_struct* a, xml_allocator& alloc)
	{
		if (a->header & impl::xml_memory_page_name_allocated_mask)
			alloc.deallocate_string(a->name);

		if (a->header & impl::xml_memory_page_value_allocated_mask)
			alloc.deallocate_string(a->value);

		alloc.deallocate_memory(a, sizeof(xml_attribute_struct), PUGI_IMPL_GETPAGE(a));
	}

	inline void destroy_node(xml_node_struct* n, xml_allocator& alloc)
	{
		if (n->header & impl::xml_memory_page_name_allocated_mask)
			alloc.deallocate_string(n->name);

		if (n->header & impl::xml_memory_page_value_allocated_mask)
			alloc.deallocate_string(n->value);

		for (xml_attribute_struct* attr = n->first_attribute; attr; )
		{
			xml_attribute_struct* next = attr->next_attribute;

			destroy_attribute(attr, alloc);

			attr = next;
		}

		for (xml_node_struct* child = n->first_child; child; )
		{
			xml_node_struct* next = child->next_sibling;

			destroy_node(child, alloc);

			child = next;
		}

		alloc.deallocate_memory(n, sizeof(xml_node_struct), PUGI_IMPL_GETPAGE(n));
	}

	inline void append_node(xml_node_struct* child, xml_node_struct* node)
	{
		child->parent = node;

		xml_node_struct* head = node->first_child;

		if (head)
		{
			xml_node_struct* tail = head->prev_sibling_c;

			tail->next_sibling = child;
			child->prev_sibling_c = tail;
			head->prev_sibling_c = child;
		}
		else
		{
			node->first_child = child;
			child->prev_sibling_c = child;
		}
	}

	inline void prepend_node(xml_node_struct* child, xml_node_struct* node)
	{
		child->parent = node;

		xml_node_struct* head = node->first_child;

		if (head)
		{
			child->prev_sibling_c = head->prev_sibling_c;
			head->prev_sibling_c = child;
		}
		else
			child->prev_sibling_c = child;

		child->next_sibling = head;
		node->first_child = child;
	}

	inline void insert_node_after(xml_node_struct* child, xml_node_struct* node)
	{
		xml_node_struct* parent = node->parent;

		child->parent = parent;

		xml_node_struct* next = node->next_sibling;

		if (next)
			next->prev_sibling_c = child;
		else
			parent->first_child->prev_sibling_c = child;

		child->next_sibling = next;
		child->prev_sibling_c = node;

		node->next_sibling = child;
	}

	inline void insert_node_before(xml_node_struct* child, xml_node_struct* node)
	{
		xml_node_struct* parent = node->parent;

		child->parent = parent;

		xml_node_struct* prev = node->prev_sibling_c;

		if (prev->next_sibling)
			prev->next_sibling = child;
		else
			parent->first_child = child;

		child->prev_sibling_c = prev;
		child->next_sibling = node;

		node->prev_sibling_c = child;
	}

	inline void remove_node(xml_node_struct* node)
	{
		xml_node_struct* parent = node->parent;

		xml_node_struct* next = node->next_sibling;
		xml_node_struct* prev = node->prev_sibling_c;

		if (next)
			next->prev_sibling_c = prev;
		else
			parent->first_child->prev_sibling_c = prev;

		if (prev->next_sibling)
			prev->next_sibling = next;
		else
			parent->first_child = next;

		node->parent = 0;
		node->prev_sibling_c = 0;
		node->next_sibling = 0;
	}

	inline void append_attribute(xml_attribute_struct* attr, xml_node_struct* node)
	{
		xml_attribute_struct* head = node->first_attribute;

		if (head)
		{
			xml_attribute_struct* tail = head->prev_attribute_c;

			tail->next_attribute = attr;
			attr->prev_attribute_c = tail;
			head->prev_attribute_c = attr;
		}
		else
		{
			node->first_attribute = attr;
			attr->prev_attribute_c = attr;
		}
	}

	inline void prepend_attribute(xml_attribute_struct* attr, xml_node_struct* node)
	{
		xml_attribute_struct* head = node->first_attribute;

		if (head)
		{
			attr->prev_attribute_c = head->prev_attribute_c;
			head->prev_attribute_c = attr;
		}
		else
			attr->prev_attribute_c = attr;

		attr->next_attribute = head;
		node->first_attribute = attr;
	}

	inline void insert_attribute_after(xml_attribute_struct* attr, xml_attribute_struct* place, xml_node_struct* node)
	{
		xml_attribute_struct* next = place->next_attribute;

		if (next)
			next->prev_attribute_c = attr;
		else
			node->first_attribute->prev_attribute_c = attr;

		attr->next_attribute = next;
		attr->prev_attribute_c = place;
		place->next_attribute = attr;
	}

	inline void insert_attribute_before(xml_attribute_struct* attr, xml_attribute_struct* place, xml_node_struct* node)
	{
		xml_attribute_struct* prev = place->prev_attribute_c;

		if (prev->next_attribute)
			prev->next_attribute = attr;
		else
			node->first_attribute = attr;

		attr->prev_attribute_c = prev;
		attr->next_attribute = place;
		place->prev_attribute_c = attr;
	}

	inline void remove_attribute(xml_attribute_struct* attr, xml_node_struct* node)
	{
		xml_attribute_struct* next = attr->next_attribute;
		xml_attribute_struct* prev = attr->prev_attribute_c;

		if (next)
			next->prev_attribute_c = prev;
		else
			node->first_attribute->prev_attribute_c = prev;

		if (prev->next_attribute)
			prev->next_attribute = next;
		else
			node->first_attribute = next;

		attr->prev_attribute_c = 0;
		attr->next_attribute = 0;
	}

	PUGI_IMPL_FN_NO_INLINE xml_node_struct* append_new_node(xml_node_struct* node, xml_allocator& alloc, xml_node_type type = node_element)
	{
		if (!alloc.reserve()) return 0;

		xml_node_struct* child = allocate_node(alloc, type);
		if (!child) return 0;

		append_node(child, node);

		return child;
	}

	PUGI_IMPL_FN_NO_INLINE xml_attribute_struct* append_new_attribute(xml_node_struct* node, xml_allocator& alloc)
	{
		if (!alloc.reserve()) return 0;

		xml_attribute_struct* attr = allocate_attribute(alloc);
		if (!attr) return 0;

		append_attribute(attr, node);

		return attr;
	}
PUGI_IMPL_NS_END

// Helper classes for code generation
PUGI_IMPL_NS_BEGIN
	struct opt_false
	{
		enum { value = 0 };
	};

	struct opt_true
	{
		enum { value = 1 };
	};
PUGI_IMPL_NS_END

// Unicode utilities
PUGI_IMPL_NS_BEGIN
	inline uint16_t endian_swap(uint16_t value)
	{
		return static_cast<uint16_t>(((value & 0xff) << 8) | (value >> 8));
	}

	inline uint32_t endian_swap(uint32_t value)
	{
		return ((value & 0xff) << 24) | ((value & 0xff00) << 8) | ((value & 0xff0000) >> 8) | (value >> 24);
	}

	struct utf8_counter
	{
		typedef size_t value_type;

		static value_type low(value_type result, uint32_t ch)
		{
			// U+0000..U+007F
			if (ch < 0x80) return result + 1;
			// U+0080..U+07FF
			else if (ch < 0x800) return result + 2;
			// U+0800..U+FFFF
			else return result + 3;
		}

		static value_type high(value_type result, uint32_t)
		{
			// U+10000..U+10FFFF
			return result + 4;
		}
	};

	struct utf8_writer
	{
		typedef uint8_t* value_type;

		static value_type low(value_type result, uint32_t ch)
		{
			// U+0000..U+007F
			if (ch < 0x80)
			{
				*result = static_cast<uint8_t>(ch);
				return result + 1;
			}
			// U+0080..U+07FF
			else if (ch < 0x800)
			{
				result[0] = static_cast<uint8_t>(0xC0 | (ch >> 6));
				result[1] = static_cast<uint8_t>(0x80 | (ch & 0x3F));
				return result + 2;
			}
			// U+0800..U+FFFF
			else
			{
				result[0] = static_cast<uint8_t>(0xE0 | (ch >> 12));
				result[1] = static_cast<uint8_t>(0x80 | ((ch >> 6) & 0x3F));
				result[2] = static_cast<uint8_t>(0x80 | (ch & 0x3F));
				return result + 3;
			}
		}

		static value_type high(value_type result, uint32_t ch)
		{
			// U+10000..U+10FFFF
			result[0] = static_cast<uint8_t>(0xF0 | (ch >> 18));
			result[1] = static_cast<uint8_t>(0x80 | ((ch >> 12) & 0x3F));
			result[2] = static_cast<uint8_t>(0x80 | ((ch >> 6) & 0x3F));
			result[3] = static_cast<uint8_t>(0x80 | (ch & 0x3F));
			return result + 4;
		}

		static value_type any(value_type result, uint32_t ch)
		{
			return (ch < 0x10000) ? low(result, ch) : high(result, ch);
		}
	};

	struct utf16_counter
	{
		typedef size_t value_type;

		static value_type low(value_type result, uint32_t)
		{
			return result + 1;
		}

		static value_type high(value_type result, uint32_t)
		{
			return result + 2;
		}
	};

	struct utf16_writer
	{
		typedef uint16_t* value_type;

		static value_type low(value_type result, uint32_t ch)
		{
			*result = static_cast<uint16_t>(ch);

			return result + 1;
		}

		static value_type high(value_type result, uint32_t ch)
		{
			uint32_t msh = static_cast<uint32_t>(ch - 0x10000) >> 10;
			uint32_t lsh = static_cast<uint32_t>(ch - 0x10000) & 0x3ff;

			result[0] = static_cast<uint16_t>(0xD800 + msh);
			result[1] = static_cast<uint16_t>(0xDC00 + lsh);

			return result + 2;
		}

		static value_type any(value_type result, uint32_t ch)
		{
			return (ch < 0x10000) ? low(result, ch) : high(result, ch);
		}
	};

	struct utf32_counter
	{
		typedef size_t value_type;

		static value_type low(value_type result, uint32_t)
		{
			return result + 1;
		}

		static value_type high(value_type result, uint32_t)
		{
			return result + 1;
		}
	};

	struct utf32_writer
	{
		typedef uint32_t* value_type;

		static value_type low(value_type result, uint32_t ch)
		{
			*result = ch;

			return result + 1;
		}

		static value_type high(value_type result, uint32_t ch)
		{
			*result = ch;

			return result + 1;
		}

		static value_type any(value_type result, uint32_t ch)
		{
			*result = ch;

			return result + 1;
		}
	};

	struct latin1_writer
	{
		typedef uint8_t* value_type;

		static value_type low(value_type result, uint32_t ch)
		{
			*result = static_cast<uint8_t>(ch > 255 ? '?' : ch);

			return result + 1;
		}

		static value_type high(value_type result, uint32_t ch)
		{
			(void)ch;

			*result = '?';

			return result + 1;
		}
	};

	struct utf8_decoder
	{
		typedef uint8_t type;

		template <typename Traits> static inline typename Traits::value_type process(const uint8_t* data, size_t size, typename Traits::value_type result, Traits)
		{
			const uint8_t utf8_byte_mask = 0x3f;

			while (size)
			{
				uint8_t lead = *data;

				// 0xxxxxxx -> U+0000..U+007F
				if (lead < 0x80)
				{
					result = Traits::low(result, lead);
					data += 1;
					size -= 1;

					// process aligned single-byte (ascii) blocks
					if ((reinterpret_cast<uintptr_t>(data) & 3) == 0)
					{
						// round-trip through void* to silence 'cast increases required alignment of target type' warnings
						while (size >= 4 && (*static_cast<const uint32_t*>(static_cast<const void*>(data)) & 0x80808080) == 0)
						{
							result = Traits::low(result, data[0]);
							result = Traits::low(result, data[1]);
							result = Traits::low(result, data[2]);
							result = Traits::low(result, data[3]);
							data += 4;
							size -= 4;
						}
					}
				}
				// 110xxxxx -> U+0080..U+07FF
				else if (static_cast<unsigned int>(lead - 0xC0) < 0x20 && size >= 2 && (data[1] & 0xc0) == 0x80)
				{
					result = Traits::low(result, ((lead & ~0xC0) << 6) | (data[1] & utf8_byte_mask));
					data += 2;
					size -= 2;
				}
				// 1110xxxx -> U+0800-U+FFFF
				else if (static_cast<unsigned int>(lead - 0xE0) < 0x10 && size >= 3 && (data[1] & 0xc0) == 0x80 && (data[2] & 0xc0) == 0x80)
				{
					result = Traits::low(result, ((lead & ~0xE0) << 12) | ((data[1] & utf8_byte_mask) << 6) | (data[2] & utf8_byte_mask));
					data += 3;
					size -= 3;
				}
				// 11110xxx -> U+10000..U+10FFFF
				else if (static_cast<unsigned int>(lead - 0xF0) < 0x08 && size >= 4 && (data[1] & 0xc0) == 0x80 && (data[2] & 0xc0) == 0x80 && (data[3] & 0xc0) == 0x80)
				{
					result = Traits::high(result, ((lead & ~0xF0) << 18) | ((data[1] & utf8_byte_mask) << 12) | ((data[2] & utf8_byte_mask) << 6) | (data[3] & utf8_byte_mask));
					data += 4;
					size -= 4;
				}
				// 10xxxxxx or 11111xxx -> invalid
				else
				{
					data += 1;
					size -= 1;
				}
			}

			return result;
		}
	};

	template <typename opt_swap> struct utf16_decoder
	{
		typedef uint16_t type;

		template <typename Traits> static inline typename Traits::value_type process(const uint16_t* data, size_t size, typename Traits::value_type result, Traits)
		{
			while (size)
			{
				uint16_t lead = opt_swap::value ? endian_swap(*data) : *data;

				// U+0000..U+D7FF
				if (lead < 0xD800)
				{
					result = Traits::low(result, lead);
					data += 1;
					size -= 1;
				}
				// U+E000..U+FFFF
				else if (static_cast<unsigned int>(lead - 0xE000) < 0x2000)
				{
					result = Traits::low(result, lead);
					data += 1;
					size -= 1;
				}
				// surrogate pair lead
				else if (static_cast<unsigned int>(lead - 0xD800) < 0x400 && size >= 2)
				{
					uint16_t next = opt_swap::value ? endian_swap(data[1]) : data[1];

					if (static_cast<unsigned int>(next - 0xDC00) < 0x400)
					{
						result = Traits::high(result, 0x10000 + ((lead & 0x3ff) << 10) + (next & 0x3ff));
						data += 2;
						size -= 2;
					}
					else
					{
						data += 1;
						size -= 1;
					}
				}
				else
				{
					data += 1;
					size -= 1;
				}
			}

			return result;
		}
	};

	template <typename opt_swap> struct utf32_decoder
	{
		typedef uint32_t type;

		template <typename Traits> static inline typename Traits::value_type process(const uint32_t* data, size_t size, typename Traits::value_type result, Traits)
		{
			while (size)
			{
				uint32_t lead = opt_swap::value ? endian_swap(*data) : *data;

				// U+0000..U+FFFF
				if (lead < 0x10000)
				{
					result = Traits::low(result, lead);
					data += 1;
					size -= 1;
				}
				// U+10000..U+10FFFF
				else
				{
					result = Traits::high(result, lead);
					data += 1;
					size -= 1;
				}
			}

			return result;
		}
	};

	struct latin1_decoder
	{
		typedef uint8_t type;

		template <typename Traits> static inline typename Traits::value_type process(const uint8_t* data, size_t size, typename Traits::value_type result, Traits)
		{
			while (size)
			{
				result = Traits::low(result, *data);
				data += 1;
				size -= 1;
			}

			return result;
		}
	};

	template <size_t size> struct wchar_selector;

	template <> struct wchar_selector<2>
	{
		typedef uint16_t type;
		typedef utf16_counter counter;
		typedef utf16_writer writer;
		typedef utf16_decoder<opt_false> decoder;
	};

	template <> struct wchar_selector<4>
	{
		typedef uint32_t type;
		typedef utf32_counter counter;
		typedef utf32_writer writer;
		typedef utf32_decoder<opt_false> decoder;
	};

	typedef wchar_selector<sizeof(wchar_t)>::counter wchar_counter;
	typedef wchar_selector<sizeof(wchar_t)>::writer wchar_writer;

	struct wchar_decoder
	{
		typedef wchar_t type;

		template <typename Traits> static inline typename Traits::value_type process(const wchar_t* data, size_t size, typename Traits::value_type result, Traits traits)
		{
			typedef wchar_selector<sizeof(wchar_t)>::decoder decoder;

			return decoder::process(reinterpret_cast<const typename decoder::type*>(data), size, result, traits);
		}
	};

#ifdef PUGIXML_WCHAR_MODE
	PUGI_IMPL_FN void convert_wchar_endian_swap(wchar_t* result, const wchar_t* data, size_t length)
	{
		for (size_t i = 0; i < length; ++i)
			result[i] = static_cast<wchar_t>(endian_swap(static_cast<wchar_selector<sizeof(wchar_t)>::type>(data[i])));
	}
#endif
PUGI_IMPL_NS_END

PUGI_IMPL_NS_BEGIN
	enum chartype_t
	{
		ct_parse_pcdata = 1,	// \0, &, \r, <
		ct_parse_attr = 2,		// \0, &, \r, ', "
		ct_parse_attr_ws = 4,	// \0, &, \r, ', ", \n, tab
		ct_space = 8,			// \r, \n, space, tab
		ct_parse_cdata = 16,	// \0, ], >, \r
		ct_parse_comment = 32,	// \0, -, >, \r
		ct_symbol = 64,			// Any symbol > 127, a-z, A-Z, 0-9, _, :, -, .
		ct_start_symbol = 128	// Any symbol > 127, a-z, A-Z, _, :
	};

	static const unsigned char chartype_table[256] =
	{
		55,  0,   0,   0,   0,   0,   0,   0,      0,   12,  12,  0,   0,   63,  0,   0,   // 0-15
		0,   0,   0,   0,   0,   0,   0,   0,      0,   0,   0,   0,   0,   0,   0,   0,   // 16-31
		8,   0,   6,   0,   0,   0,   7,   6,      0,   0,   0,   0,   0,   96,  64,  0,   // 32-47
		64,  64,  64,  64,  64,  64,  64,  64,     64,  64,  192, 0,   1,   0,   48,  0,   // 48-63
		0,   192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192, // 64-79
		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 0,   0,   16,  0,   192, // 80-95
		0,   192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192, // 96-111
		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 0, 0, 0, 0, 0,           // 112-127

		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192, // 128+
		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192,
		192, 192, 192, 192, 192, 192, 192, 192,    192, 192, 192, 192, 192, 192, 192, 192
	};

	enum chartypex_t
	{
		ctx_special_pcdata = 1,   // Any symbol >= 0 and < 32 (except \t, \r, \n), &, <, >
		ctx_special_attr = 2,     // Any symbol >= 0 and < 32, &, <, ", '
		ctx_start_symbol = 4,	  // Any symbol > 127, a-z, A-Z, _
		ctx_digit = 8,			  // 0-9
		ctx_symbol = 16			  // Any symbol > 127, a-z, A-Z, 0-9, _, -, .
	};

	static const unsigned char chartypex_table[256] =
	{
		3,  3,  3,  3,  3,  3,  3,  3,     3,  2,  2,  3,  3,  2,  3,  3,     // 0-15
		3,  3,  3,  3,  3,  3,  3,  3,     3,  3,  3,  3,  3,  3,  3,  3,     // 16-31
		0,  0,  2,  0,  0,  0,  3,  2,     0,  0,  0,  0,  0, 16, 16,  0,     // 32-47
		24, 24, 24, 24, 24, 24, 24, 24,    24, 24, 0,  0,  3,  0,  1,  0,     // 48-63

		0,  20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,    // 64-79
		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 0,  0,  0,  0,  20,    // 80-95
		0,  20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,    // 96-111
		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 0,  0,  0,  0,  0,     // 112-127

		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,    // 128+
		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20,
		20, 20, 20, 20, 20, 20, 20, 20,    20, 20, 20, 20, 20, 20, 20, 20
	};

#ifdef PUGIXML_WCHAR_MODE
	#define PUGI_IMPL_IS_CHARTYPE_IMPL(c, ct, table) ((static_cast<unsigned int>(c) < 128 ? table[static_cast<unsigned int>(c)] : table[128]) & (ct))
#else
	#define PUGI_IMPL_IS_CHARTYPE_IMPL(c, ct, table) (table[static_cast<unsigned char>(c)] & (ct))
#endif

	#define PUGI_IMPL_IS_CHARTYPE(c, ct) PUGI_IMPL_IS_CHARTYPE_IMPL(c, ct, chartype_table)
	#define PUGI_IMPL_IS_CHARTYPEX(c, ct) PUGI_IMPL_IS_CHARTYPE_IMPL(c, ct, chartypex_table)

	PUGI_IMPL_FN bool is_little_endian()
	{
		unsigned int ui = 1;

		return *reinterpret_cast<unsigned char*>(&ui) == 1;
	}

	PUGI_IMPL_FN xml_encoding get_wchar_encoding()
	{
		PUGI_IMPL_STATIC_ASSERT(sizeof(wchar_t) == 2 || sizeof(wchar_t) == 4);

		if (sizeof(wchar_t) == 2)
			return is_little_endian() ? encoding_utf16_le : encoding_utf16_be;
		else
			return is_little_endian() ? encoding_utf32_le : encoding_utf32_be;
	}

	PUGI_IMPL_FN bool parse_declaration_encoding(const uint8_t* data, size_t size, const uint8_t*& out_encoding, size_t& out_length)
	{
	#define PUGI_IMPL_SCANCHAR(ch) { if (offset >= size || data[offset] != ch) return false; offset++; }
	#define PUGI_IMPL_SCANCHARTYPE(ct) { while (offset < size && PUGI_IMPL_IS_CHARTYPE(data[offset], ct)) offset++; }

		// check if we have a non-empty XML declaration
		if (size < 6 || !((data[0] == '<') & (data[1] == '?') & (data[2] == 'x') & (data[3] == 'm') & (data[4] == 'l') && PUGI_IMPL_IS_CHARTYPE(data[5], ct_space)))
			return false;

		// scan XML declaration until the encoding field
		for (size_t i = 6; i + 1 < size; ++i)
		{
			// declaration can not contain ? in quoted values
			if (data[i] == '?')
				return false;

			if (data[i] == 'e' && data[i + 1] == 'n')
			{
				size_t offset = i;

				// encoding follows the version field which can't contain 'en' so this has to be the encoding if XML is well formed
				PUGI_IMPL_SCANCHAR('e'); PUGI_IMPL_SCANCHAR('n'); PUGI_IMPL_SCANCHAR('c'); PUGI_IMPL_SCANCHAR('o');
				PUGI_IMPL_SCANCHAR('d'); PUGI_IMPL_SCANCHAR('i'); PUGI_IMPL_SCANCHAR('n'); PUGI_IMPL_SCANCHAR('g');

				// S? = S?
				PUGI_IMPL_SCANCHARTYPE(ct_space);
				PUGI_IMPL_SCANCHAR('=');
				PUGI_IMPL_SCANCHARTYPE(ct_space);

				// the only two valid delimiters are ' and "
				uint8_t delimiter = (offset < size && data[offset] == '"') ? '"' : '\'';

				PUGI_IMPL_SCANCHAR(delimiter);

				size_t start = offset;

				out_encoding = data + offset;

				PUGI_IMPL_SCANCHARTYPE(ct_symbol);

				out_length = offset - start;

				PUGI_IMPL_SCANCHAR(delimiter);

				return true;
			}
		}

		return false;

	#undef PUGI_IMPL_SCANCHAR
	#undef PUGI_IMPL_SCANCHARTYPE
	}

	PUGI_IMPL_FN xml_encoding guess_buffer_encoding(const uint8_t* data, size_t size)
	{
		// skip encoding autodetection if input buffer is too small
		if (size < 4) return encoding_utf8;

		uint8_t d0 = data[0], d1 = data[1], d2 = data[2], d3 = data[3];

		// look for BOM in first few bytes
		if (d0 == 0 && d1 == 0 && d2 == 0xfe && d3 == 0xff) return encoding_utf32_be;
		if (d0 == 0xff && d1 == 0xfe && d2 == 0 && d3 == 0) return encoding_utf32_le;
		if (d0 == 0xfe && d1 == 0xff) return encoding_utf16_be;
		if (d0 == 0xff && d1 == 0xfe) return encoding_utf16_le;
		if (d0 == 0xef && d1 == 0xbb && d2 == 0xbf) return encoding_utf8;

		// look for <, <? or <?xm in various encodings
		if (d0 == 0 && d1 == 0 && d2 == 0 && d3 == 0x3c) return encoding_utf32_be;
		if (d0 == 0x3c && d1 == 0 && d2 == 0 && d3 == 0) return encoding_utf32_le;
		if (d0 == 0 && d1 == 0x3c && d2 == 0 && d3 == 0x3f) return encoding_utf16_be;
		if (d0 == 0x3c && d1 == 0 && d2 == 0x3f && d3 == 0) return encoding_utf16_le;

		// look for utf16 < followed by node name (this may fail, but is better than utf8 since it's zero terminated so early)
		if (d0 == 0 && d1 == 0x3c) return encoding_utf16_be;
		if (d0 == 0x3c && d1 == 0) return encoding_utf16_le;

		// no known BOM detected; parse declaration
		const uint8_t* enc = 0;
		size_t enc_length = 0;

		if (d0 == 0x3c && d1 == 0x3f && d2 == 0x78 && d3 == 0x6d && parse_declaration_encoding(data, size, enc, enc_length))
		{
			// iso-8859-1 (case-insensitive)
			if (enc_length == 10
				&& (enc[0] | ' ') == 'i' && (enc[1] | ' ') == 's' && (enc[2] | ' ') == 'o'
				&& enc[3] == '-' && enc[4] == '8' && enc[5] == '8' && enc[6] == '5' && enc[7] == '9'
				&& enc[8] == '-' && enc[9] == '1')
				return encoding_latin1;

			// latin1 (case-insensitive)
			if (enc_length == 6
				&& (enc[0] | ' ') == 'l' && (enc[1] | ' ') == 'a' && (enc[2] | ' ') == 't'
				&& (enc[3] | ' ') == 'i' && (enc[4] | ' ') == 'n'
				&& enc[5] == '1')
				return encoding_latin1;
		}

		return encoding_utf8;
	}

	PUGI_IMPL_FN xml_encoding get_buffer_encoding(xml_encoding encoding, const void* contents, size_t size)
	{
		// replace wchar encoding with utf implementation
		if (encoding == encoding_wchar) return get_wchar_encoding();

		// replace utf16 encoding with utf16 with specific endianness
		if (encoding == encoding_utf16) return is_little_endian() ? encoding_utf16_le : encoding_utf16_be;

		// replace utf32 encoding with utf32 with specific endianness
		if (encoding == encoding_utf32) return is_little_endian() ? encoding_utf32_le : encoding_utf32_be;

		// only do autodetection if no explicit encoding is requested
		if (encoding != encoding_auto) return encoding;

		// try to guess encoding (based on XML specification, Appendix F.1)
		const uint8_t* data = static_cast<const uint8_t*>(contents);

		return guess_buffer_encoding(data, size);
	}

	PUGI_IMPL_FN bool get_mutable_buffer(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, bool is_mutable)
	{
		size_t length = size / sizeof(char_t);

		if (is_mutable)
		{
			out_buffer = static_cast<char_t*>(const_cast<void*>(contents));
			out_length = length;
		}
		else
		{
			char_t* buffer = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
			if (!buffer) return false;

			if (contents)
				memcpy(buffer, contents, length * sizeof(char_t));
			else
				assert(length == 0);

			buffer[length] = 0;

			out_buffer = buffer;
			out_length = length + 1;
		}

		return true;
	}

#ifdef PUGIXML_WCHAR_MODE
	PUGI_IMPL_FN bool need_endian_swap_utf(xml_encoding le, xml_encoding re)
	{
		return (le == encoding_utf16_be && re == encoding_utf16_le) || (le == encoding_utf16_le && re == encoding_utf16_be) ||
			   (le == encoding_utf32_be && re == encoding_utf32_le) || (le == encoding_utf32_le && re == encoding_utf32_be);
	}

	PUGI_IMPL_FN bool convert_buffer_endian_swap(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, bool is_mutable)
	{
		const char_t* data = static_cast<const char_t*>(contents);
		size_t length = size / sizeof(char_t);

		if (is_mutable)
		{
			char_t* buffer = const_cast<char_t*>(data);

			convert_wchar_endian_swap(buffer, data, length);

			out_buffer = buffer;
			out_length = length;
		}
		else
		{
			char_t* buffer = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
			if (!buffer) return false;

			convert_wchar_endian_swap(buffer, data, length);
			buffer[length] = 0;

			out_buffer = buffer;
			out_length = length + 1;
		}

		return true;
	}

	template <typename D> PUGI_IMPL_FN bool convert_buffer_generic(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, D)
	{
		const typename D::type* data = static_cast<const typename D::type*>(contents);
		size_t data_length = size / sizeof(typename D::type);

		// first pass: get length in wchar_t units
		size_t length = D::process(data, data_length, 0, wchar_counter());

		// allocate buffer of suitable length
		char_t* buffer = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
		if (!buffer) return false;

		// second pass: convert utf16 input to wchar_t
		wchar_writer::value_type obegin = reinterpret_cast<wchar_writer::value_type>(buffer);
		wchar_writer::value_type oend = D::process(data, data_length, obegin, wchar_writer());

		assert(oend == obegin + length);
		*oend = 0;

		out_buffer = buffer;
		out_length = length + 1;

		return true;
	}

	PUGI_IMPL_FN bool convert_buffer(char_t*& out_buffer, size_t& out_length, xml_encoding encoding, const void* contents, size_t size, bool is_mutable)
	{
		// get native encoding
		xml_encoding wchar_encoding = get_wchar_encoding();

		// fast path: no conversion required
		if (encoding == wchar_encoding)
			return get_mutable_buffer(out_buffer, out_length, contents, size, is_mutable);

		// only endian-swapping is required
		if (need_endian_swap_utf(encoding, wchar_encoding))
			return convert_buffer_endian_swap(out_buffer, out_length, contents, size, is_mutable);

		// source encoding is utf8
		if (encoding == encoding_utf8)
			return convert_buffer_generic(out_buffer, out_length, contents, size, utf8_decoder());

		// source encoding is utf16
		if (encoding == encoding_utf16_be || encoding == encoding_utf16_le)
		{
			xml_encoding native_encoding = is_little_endian() ? encoding_utf16_le : encoding_utf16_be;

			return (native_encoding == encoding) ?
				convert_buffer_generic(out_buffer, out_length, contents, size, utf16_decoder<opt_false>()) :
				convert_buffer_generic(out_buffer, out_length, contents, size, utf16_decoder<opt_true>());
		}

		// source encoding is utf32
		if (encoding == encoding_utf32_be || encoding == encoding_utf32_le)
		{
			xml_encoding native_encoding = is_little_endian() ? encoding_utf32_le : encoding_utf32_be;

			return (native_encoding == encoding) ?
				convert_buffer_generic(out_buffer, out_length, contents, size, utf32_decoder<opt_false>()) :
				convert_buffer_generic(out_buffer, out_length, contents, size, utf32_decoder<opt_true>());
		}

		// source encoding is latin1
		if (encoding == encoding_latin1)
			return convert_buffer_generic(out_buffer, out_length, contents, size, latin1_decoder());

		assert(false && "Invalid encoding"); // unreachable
		return false;
	}
#else
	template <typename D> PUGI_IMPL_FN bool convert_buffer_generic(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, D)
	{
		const typename D::type* data = static_cast<const typename D::type*>(contents);
		size_t data_length = size / sizeof(typename D::type);

		// first pass: get length in utf8 units
		size_t length = D::process(data, data_length, 0, utf8_counter());

		// allocate buffer of suitable length
		char_t* buffer = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
		if (!buffer) return false;

		// second pass: convert utf16 input to utf8
		uint8_t* obegin = reinterpret_cast<uint8_t*>(buffer);
		uint8_t* oend = D::process(data, data_length, obegin, utf8_writer());

		assert(oend == obegin + length);
		*oend = 0;

		out_buffer = buffer;
		out_length = length + 1;

		return true;
	}

	PUGI_IMPL_FN size_t get_latin1_7bit_prefix_length(const uint8_t* data, size_t size)
	{
		for (size_t i = 0; i < size; ++i)
			if (data[i] > 127)
				return i;

		return size;
	}

	PUGI_IMPL_FN bool convert_buffer_latin1(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, bool is_mutable)
	{
		const uint8_t* data = static_cast<const uint8_t*>(contents);
		size_t data_length = size;

		// get size of prefix that does not need utf8 conversion
		size_t prefix_length = get_latin1_7bit_prefix_length(data, data_length);
		assert(prefix_length <= data_length);

		const uint8_t* postfix = data + prefix_length;
		size_t postfix_length = data_length - prefix_length;

		// if no conversion is needed, just return the original buffer
		if (postfix_length == 0) return get_mutable_buffer(out_buffer, out_length, contents, size, is_mutable);

		// first pass: get length in utf8 units
		size_t length = prefix_length + latin1_decoder::process(postfix, postfix_length, 0, utf8_counter());

		// allocate buffer of suitable length
		char_t* buffer = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
		if (!buffer) return false;

		// second pass: convert latin1 input to utf8
		memcpy(buffer, data, prefix_length);

		uint8_t* obegin = reinterpret_cast<uint8_t*>(buffer);
		uint8_t* oend = latin1_decoder::process(postfix, postfix_length, obegin + prefix_length, utf8_writer());

		assert(oend == obegin + length);
		*oend = 0;

		out_buffer = buffer;
		out_length = length + 1;

		return true;
	}

	PUGI_IMPL_FN bool convert_buffer(char_t*& out_buffer, size_t& out_length, xml_encoding encoding, const void* contents, size_t size, bool is_mutable)
	{
		// fast path: no conversion required
		if (encoding == encoding_utf8)
			return get_mutable_buffer(out_buffer, out_length, contents, size, is_mutable);

		// source encoding is utf16
		if (encoding == encoding_utf16_be || encoding == encoding_utf16_le)
		{
			xml_encoding native_encoding = is_little_endian() ? encoding_utf16_le : encoding_utf16_be;

			return (native_encoding == encoding) ?
				convert_buffer_generic(out_buffer, out_length, contents, size, utf16_decoder<opt_false>()) :
				convert_buffer_generic(out_buffer, out_length, contents, size, utf16_decoder<opt_true>());
		}

		// source encoding is utf32
		if (encoding == encoding_utf32_be || encoding == encoding_utf32_le)
		{
			xml_encoding native_encoding = is_little_endian() ? encoding_utf32_le : encoding_utf32_be;

			return (native_encoding == encoding) ?
				convert_buffer_generic(out_buffer, out_length, contents, size, utf32_decoder<opt_false>()) :
				convert_buffer_generic(out_buffer, out_length, contents, size, utf32_decoder<opt_true>());
		}

		// source encoding is latin1
		if (encoding == encoding_latin1)
			return convert_buffer_latin1(out_buffer, out_length, contents, size, is_mutable);

		assert(false && "Invalid encoding"); // unreachable
		return false;
	}
#endif

	PUGI_IMPL_FN size_t as_utf8_begin(const wchar_t* str, size_t length)
	{
		// get length in utf8 characters
		return wchar_decoder::process(str, length, 0, utf8_counter());
	}

	PUGI_IMPL_FN void as_utf8_end(char* buffer, size_t size, const wchar_t* str, size_t length)
	{
		// convert to utf8
		uint8_t* begin = reinterpret_cast<uint8_t*>(buffer);
		uint8_t* end = wchar_decoder::process(str, length, begin, utf8_writer());

		assert(begin + size == end);
		(void)!end;
		(void)!size;
	}

#ifndef PUGIXML_NO_STL
	PUGI_IMPL_FN std::string as_utf8_impl(const wchar_t* str, size_t length)
	{
		// first pass: get length in utf8 characters
		size_t size = as_utf8_begin(str, length);

		// allocate resulting string
		std::string result;
		result.resize(size);

		// second pass: convert to utf8
		if (size > 0) as_utf8_end(&result[0], size, str, length);

		return result;
	}

	PUGI_IMPL_FN std::basic_string<wchar_t> as_wide_impl(const char* str, size_t size)
	{
		const uint8_t* data = reinterpret_cast<const uint8_t*>(str);

		// first pass: get length in wchar_t units
		size_t length = utf8_decoder::process(data, size, 0, wchar_counter());

		// allocate resulting string
		std::basic_string<wchar_t> result;
		result.resize(length);

		// second pass: convert to wchar_t
		if (length > 0)
		{
			wchar_writer::value_type begin = reinterpret_cast<wchar_writer::value_type>(&result[0]);
			wchar_writer::value_type end = utf8_decoder::process(data, size, begin, wchar_writer());

			assert(begin + length == end);
			(void)!end;
		}

		return result;
	}
#endif

	template <typename Header>
	inline bool strcpy_insitu_allow(size_t length, const Header& header, uintptr_t header_mask, char_t* target)
	{
		// never reuse shared memory
		if (header & xml_memory_page_contents_shared_mask) return false;

		size_t target_length = strlength(target);

		// always reuse document buffer memory if possible
		if ((header & header_mask) == 0) return target_length >= length;

		// reuse heap memory if waste is not too great
		const size_t reuse_threshold = 32;

		return target_length >= length && (target_length < reuse_threshold || target_length - length < target_length / 2);
	}

	template <typename String, typename Header>
	PUGI_IMPL_FN bool strcpy_insitu(String& dest, Header& header, uintptr_t header_mask, const char_t* source, size_t source_length)
	{
		assert((header & header_mask) == 0 || dest); // header bit indicates whether dest was previously allocated

		if (source_length == 0)
		{
			// empty string and null pointer are equivalent, so just deallocate old memory
			xml_allocator* alloc = PUGI_IMPL_GETPAGE_IMPL(header)->allocator;

			if (header & header_mask) alloc->deallocate_string(dest);

			// mark the string as not allocated
			dest = 0;
			header &= ~header_mask;

			return true;
		}
		else if (dest && strcpy_insitu_allow(source_length, header, header_mask, dest))
		{
			// we can reuse old buffer, so just copy the new data (including zero terminator)
			memcpy(dest, source, source_length * sizeof(char_t));
			dest[source_length] = 0;

			return true;
		}
		else
		{
			xml_allocator* alloc = PUGI_IMPL_GETPAGE_IMPL(header)->allocator;

			if (!alloc->reserve()) return false;

			// allocate new buffer
			char_t* buf = alloc->allocate_string(source_length + 1);
			if (!buf) return false;

			// copy the string (including zero terminator)
			memcpy(buf, source, source_length * sizeof(char_t));
			buf[source_length] = 0;

			// deallocate old buffer (*after* the above to protect against overlapping memory and/or allocation failures)
			if (header & header_mask) alloc->deallocate_string(dest);

			// the string is now allocated, so set the flag
			dest = buf;
			header |= header_mask;

			return true;
		}
	}

	struct gap
	{
		char_t* end;
		size_t size;

		gap(): end(0), size(0)
		{
		}

		// Push new gap, move s count bytes further (skipping the gap).
		// Collapse previous gap.
		void push(char_t*& s, size_t count)
		{
			if (end) // there was a gap already; collapse it
			{
				// Move [old_gap_end, new_gap_start) to [old_gap_start, ...)
				assert(s >= end);
				memmove(end - size, end, reinterpret_cast<char*>(s) - reinterpret_cast<char*>(end));
			}

			s += count; // end of current gap

			// "merge" two gaps
			end = s;
			size += count;
		}

		// Collapse all gaps, return past-the-end pointer
		char_t* flush(char_t* s)
		{
			if (end)
			{
				// Move [old_gap_end, current_pos) to [old_gap_start, ...)
				assert(s >= end);
				memmove(end - size, end, reinterpret_cast<char*>(s) - reinterpret_cast<char*>(end));

				return s - size;
			}
			else return s;
		}
	};

	PUGI_IMPL_FN char_t* strconv_escape(char_t* s, gap& g)
	{
		char_t* stre = s + 1;

		switch (*stre)
		{
			case '#':	// &#...
			{
				unsigned int ucsc = 0;

				if (stre[1] == 'x') // &#x... (hex code)
				{
					stre += 2;

					char_t ch = *stre;

					if (ch == ';') return stre;

					for (;;)
					{
						if (static_cast<unsigned int>(ch - '0') <= 9)
							ucsc = 16 * ucsc + (ch - '0');
						else if (static_cast<unsigned int>((ch | ' ') - 'a') <= 5)
							ucsc = 16 * ucsc + ((ch | ' ') - 'a' + 10);
						else if (ch == ';')
							break;
						else // cancel
							return stre;

						ch = *++stre;
					}

					++stre;
				}
				else	// &#... (dec code)
				{
					char_t ch = *++stre;

					if (ch == ';') return stre;

					for (;;)
					{
						if (static_cast<unsigned int>(ch - '0') <= 9)
							ucsc = 10 * ucsc + (ch - '0');
						else if (ch == ';')
							break;
						else // cancel
							return stre;

						ch = *++stre;
					}

					++stre;
				}

			#ifdef PUGIXML_WCHAR_MODE
				s = reinterpret_cast<char_t*>(wchar_writer::any(reinterpret_cast<wchar_writer::value_type>(s), ucsc));
			#else
				s = reinterpret_cast<char_t*>(utf8_writer::any(reinterpret_cast<uint8_t*>(s), ucsc));
			#endif

				g.push(s, stre - s);
				return stre;
			}

			case 'a':	// &a
			{
				++stre;

				if (*stre == 'm') // &am
				{
					if (*++stre == 'p' && *++stre == ';') // &amp;
					{
						*s++ = '&';
						++stre;

						g.push(s, stre - s);
						return stre;
					}
				}
				else if (*stre == 'p') // &ap
				{
					if (*++stre == 'o' && *++stre == 's' && *++stre == ';') // &apos;
					{
						*s++ = '\'';
						++stre;

						g.push(s, stre - s);
						return stre;
					}
				}
				break;
			}

			case 'g': // &g
			{
				if (*++stre == 't' && *++stre == ';') // &gt;
				{
					*s++ = '>';
					++stre;

					g.push(s, stre - s);
					return stre;
				}
				break;
			}

			case 'l': // &l
			{
				if (*++stre == 't' && *++stre == ';') // &lt;
				{
					*s++ = '<';
					++stre;

					g.push(s, stre - s);
					return stre;
				}
				break;
			}

			case 'q': // &q
			{
				if (*++stre == 'u' && *++stre == 'o' && *++stre == 't' && *++stre == ';') // &quot;
				{
					*s++ = '"';
					++stre;

					g.push(s, stre - s);
					return stre;
				}
				break;
			}

			default:
				break;
		}

		return stre;
	}

	// Parser utilities
	#define PUGI_IMPL_ENDSWITH(c, e)        ((c) == (e) || ((c) == 0 && endch == (e)))
	#define PUGI_IMPL_SKIPWS()              { while (PUGI_IMPL_IS_CHARTYPE(*s, ct_space)) ++s; }
	#define PUGI_IMPL_OPTSET(OPT)           ( optmsk & (OPT) )
	#define PUGI_IMPL_PUSHNODE(TYPE)        { cursor = append_new_node(cursor, *alloc, TYPE); if (!cursor) PUGI_IMPL_THROW_ERROR(status_out_of_memory, s); }
	#define PUGI_IMPL_POPNODE()             { cursor = cursor->parent; }
	#define PUGI_IMPL_SCANFOR(X)            { while (*s != 0 && !(X)) ++s; }
	#define PUGI_IMPL_SCANWHILE(X)          { while (X) ++s; }
	#define PUGI_IMPL_SCANWHILE_UNROLL(X)   { for (;;) { char_t ss = s[0]; if (PUGI_IMPL_UNLIKELY(!(X))) { break; } ss = s[1]; if (PUGI_IMPL_UNLIKELY(!(X))) { s += 1; break; } ss = s[2]; if (PUGI_IMPL_UNLIKELY(!(X))) { s += 2; break; } ss = s[3]; if (PUGI_IMPL_UNLIKELY(!(X))) { s += 3; break; } s += 4; } }
	#define PUGI_IMPL_ENDSEG()              { ch = *s; *s = 0; ++s; }
	#define PUGI_IMPL_THROW_ERROR(err, m)   return error_offset = m, error_status = err, static_cast<char_t*>(0)
	#define PUGI_IMPL_CHECK_ERROR(err, m)   { if (*s == 0) PUGI_IMPL_THROW_ERROR(err, m); }

	PUGI_IMPL_FN char_t* strconv_comment(char_t* s, char_t endch)
	{
		gap g;

		while (true)
		{
			PUGI_IMPL_SCANWHILE_UNROLL(!PUGI_IMPL_IS_CHARTYPE(ss, ct_parse_comment));

			if (*s == '\r') // Either a single 0x0d or 0x0d 0x0a pair
			{
				*s++ = '\n'; // replace first one with 0x0a

				if (*s == '\n') g.push(s, 1);
			}
			else if (s[0] == '-' && s[1] == '-' && PUGI_IMPL_ENDSWITH(s[2], '>')) // comment ends here
			{
				*g.flush(s) = 0;

				return s + (s[2] == '>' ? 3 : 2);
			}
			else if (*s == 0)
			{
				return 0;
			}
			else ++s;
		}
	}

	PUGI_IMPL_FN char_t* strconv_cdata(char_t* s, char_t endch)
	{
		gap g;

		while (true)
		{
			PUGI_IMPL_SCANWHILE_UNROLL(!PUGI_IMPL_IS_CHARTYPE(ss, ct_parse_cdata));

			if (*s == '\r') // Either a single 0x0d or 0x0d 0x0a pair
			{
				*s++ = '\n'; // replace first one with 0x0a

				if (*s == '\n') g.push(s, 1);
			}
			else if (s[0] == ']' && s[1] == ']' && PUGI_IMPL_ENDSWITH(s[2], '>')) // CDATA ends here
			{
				*g.flush(s) = 0;

				return s + 1;
			}
			else if (*s == 0)
			{
				return 0;
			}
			else ++s;
		}
	}

	typedef char_t* (*strconv_pcdata_t)(char_t*);

	template <typename opt_trim, typename opt_eol, typename opt_escape> struct strconv_pcdata_impl
	{
		static char_t* parse(char_t* s)
		{
			gap g;

			char_t* begin = s;

			while (true)
			{
				PUGI_IMPL_SCANWHILE_UNROLL(!PUGI_IMPL_IS_CHARTYPE(ss, ct_parse_pcdata));

				if (*s == '<') // PCDATA ends here
				{
					char_t* end = g.flush(s);

					if (opt_trim::value)
						while (end > begin && PUGI_IMPL_IS_CHARTYPE(end[-1], ct_space))
							--end;

					*end = 0;

					return s + 1;
				}
				else if (opt_eol::value && *s == '\r') // Either a single 0x0d or 0x0d 0x0a pair
				{
					*s++ = '\n'; // replace first one with 0x0a

					if (*s == '\n') g.push(s, 1);
				}
				else if (opt_escape::value && *s == '&')
				{
					s = strconv_escape(s, g);
				}
				else if (*s == 0)
				{
					char_t* end = g.flush(s);

					if (opt_trim::value)
						while (end > begin && PUGI_IMPL_IS_CHARTYPE(end[-1], ct_space))
							--end;

					*end = 0;

					return s;
				}
				else ++s;
			}
		}
	};

	PUGI_IMPL_FN strconv_pcdata_t get_strconv_pcdata(unsigned int optmask)
	{
		PUGI_IMPL_STATIC_ASSERT(parse_escapes == 0x10 && parse_eol == 0x20 && parse_trim_pcdata == 0x0800);

		switch (((optmask >> 4) & 3) | ((optmask >> 9) & 4)) // get bitmask for flags (trim eol escapes); this simultaneously checks 3 options from assertion above
		{
		case 0: return strconv_pcdata_impl<opt_false, opt_false, opt_false>::parse;
		case 1: return strconv_pcdata_impl<opt_false, opt_false, opt_true>::parse;
		case 2: return strconv_pcdata_impl<opt_false, opt_true, opt_false>::parse;
		case 3: return strconv_pcdata_impl<opt_false, opt_true, opt_true>::parse;
		case 4: return strconv_pcdata_impl<opt_true, opt_false, opt_false>::parse;
		case 5: return strconv_pcdata_impl<opt_true, opt_false, opt_true>::parse;
		case 6: return strconv_pcdata_impl<opt_true, opt_true, opt_false>::parse;
		case 7: return strconv_pcdata_impl<opt_true, opt_true, opt_true>::parse;
		default: assert(false); return 0; // unreachable
		}
	}

	typedef char_t* (*strconv_attribute_t)(char_t*, char_t);

	template <typename opt_escape> struct strconv_attribute_impl
	{
		static char_t* parse_wnorm(char_t* s, char_t end_quote)
		{
			gap g;

			// trim leading whitespaces
			if (PUGI_IMPL_IS_CHARTYPE(*s, ct_space))
			{
				char_t* str = s;

				do ++str;
				while (PUGI_IMPL_IS_CHARTYPE(*str, ct_space));

				g.push(s, str - s);
			}

			while (true)
			{
				PUGI_IMPL_SCANWHILE_UNROLL(!PUGI_IMPL_IS_CHARTYPE(ss, ct_parse_attr_ws | ct_space));

				if (*s == end_quote)
				{
					char_t* str = g.flush(s);

					do *str-- = 0;
					while (PUGI_IMPL_IS_CHARTYPE(*str, ct_space));

					return s + 1;
				}
				else if (PUGI_IMPL_IS_CHARTYPE(*s, ct_space))
				{
					*s++ = ' ';

					if (PUGI_IMPL_IS_CHARTYPE(*s, ct_space))
					{
						char_t* str = s + 1;
						while (PUGI_IMPL_IS_CHARTYPE(*str, ct_space)) ++str;

						g.push(s, str - s);
					}
				}
				else if (opt_escape::value && *s == '&')
				{
					s = strconv_escape(s, g);
				}
				else if (!*s)
				{
					return 0;
				}
				else ++s;
			}
		}

		static char_t* parse_wconv(char_t* s, char_t end_quote)
		{
			gap g;

			while (true)
			{
				PUGI_IMPL_SCANWHILE_UNROLL(!PUGI_IMPL_IS_CHARTYPE(ss, ct_parse_attr_ws));

				if (*s == end_quote)
				{
					*g.flush(s) = 0;

					return s + 1;
				}
				else if (PUGI_IMPL_IS_CHARTYPE(*s, ct_space))
				{
					if (*s == '\r')
					{
						*s++ = ' ';

						if (*s == '\n') g.push(s, 1);
					}
					else *s++ = ' ';
				}
				else if (opt_escape::value && *s == '&')
				{
					s = strconv_escape(s, g);
				}
				else if (!*s)
				{
					return 0;
				}
				else ++s;
			}
		}

		static char_t* parse_eol(char_t* s, char_t end_quote)
		{
			gap g;

			while (true)
			{
				PUGI_IMPL_SCANWHILE_UNROLL(!PUGI_IMPL_IS_CHARTYPE(ss, ct_parse_attr));

				if (*s == end_quote)
				{
					*g.flush(s) = 0;

					return s + 1;
				}
				else if (*s == '\r')
				{
					*s++ = '\n';

					if (*s == '\n') g.push(s, 1);
				}
				else if (opt_escape::value && *s == '&')
				{
					s = strconv_escape(s, g);
				}
				else if (!*s)
				{
					return 0;
				}
				else ++s;
			}
		}

		static char_t* parse_simple(char_t* s, char_t end_quote)
		{
			gap g;

			while (true)
			{
				PUGI_IMPL_SCANWHILE_UNROLL(!PUGI_IMPL_IS_CHARTYPE(ss, ct_parse_attr));

				if (*s == end_quote)
				{
					*g.flush(s) = 0;

					return s + 1;
				}
				else if (opt_escape::value && *s == '&')
				{
					s = strconv_escape(s, g);
				}
				else if (!*s)
				{
					return 0;
				}
				else ++s;
			}
		}
	};

	PUGI_IMPL_FN strconv_attribute_t get_strconv_attribute(unsigned int optmask)
	{
		PUGI_IMPL_STATIC_ASSERT(parse_escapes == 0x10 && parse_eol == 0x20 && parse_wconv_attribute == 0x40 && parse_wnorm_attribute == 0x80);

		switch ((optmask >> 4) & 15) // get bitmask for flags (wnorm wconv eol escapes); this simultaneously checks 4 options from assertion above
		{
		case 0:  return strconv_attribute_impl<opt_false>::parse_simple;
		case 1:  return strconv_attribute_impl<opt_true>::parse_simple;
		case 2:  return strconv_attribute_impl<opt_false>::parse_eol;
		case 3:  return strconv_attribute_impl<opt_true>::parse_eol;
		case 4:  return strconv_attribute_impl<opt_false>::parse_wconv;
		case 5:  return strconv_attribute_impl<opt_true>::parse_wconv;
		case 6:  return strconv_attribute_impl<opt_false>::parse_wconv;
		case 7:  return strconv_attribute_impl<opt_true>::parse_wconv;
		case 8:  return strconv_attribute_impl<opt_false>::parse_wnorm;
		case 9:  return strconv_attribute_impl<opt_true>::parse_wnorm;
		case 10: return strconv_attribute_impl<opt_false>::parse_wnorm;
		case 11: return strconv_attribute_impl<opt_true>::parse_wnorm;
		case 12: return strconv_attribute_impl<opt_false>::parse_wnorm;
		case 13: return strconv_attribute_impl<opt_true>::parse_wnorm;
		case 14: return strconv_attribute_impl<opt_false>::parse_wnorm;
		case 15: return strconv_attribute_impl<opt_true>::parse_wnorm;
		default: assert(false); return 0; // unreachable
		}
	}

	inline xml_parse_result make_parse_result(xml_parse_status status, ptrdiff_t offset = 0)
	{
		xml_parse_result result;
		result.status = status;
		result.offset = offset;

		return result;
	}

	struct xml_parser
	{
		xml_allocator* alloc;
		char_t* error_offset;
		xml_parse_status error_status;

		xml_parser(xml_allocator* alloc_): alloc(alloc_), error_offset(0), error_status(status_ok)
		{
		}

		// DOCTYPE consists of nested sections of the following possible types:
		// <!-- ... -->, <? ... ?>, "...", '...'
		// <![...]]>
		// <!...>
		// First group can not contain nested groups
		// Second group can contain nested groups of the same type
		// Third group can contain all other groups
		char_t* parse_doctype_primitive(char_t* s)
		{
			if (*s == '"' || *s == '\'')
			{
				// quoted string
				char_t ch = *s++;
				PUGI_IMPL_SCANFOR(*s == ch);
				if (!*s) PUGI_IMPL_THROW_ERROR(status_bad_doctype, s);

				s++;
			}
			else if (s[0] == '<' && s[1] == '?')
			{
				// <? ... ?>
				s += 2;
				PUGI_IMPL_SCANFOR(s[0] == '?' && s[1] == '>'); // no need for ENDSWITH because ?> can't terminate proper doctype
				if (!*s) PUGI_IMPL_THROW_ERROR(status_bad_doctype, s);

				s += 2;
			}
			else if (s[0] == '<' && s[1] == '!' && s[2] == '-' && s[3] == '-')
			{
				s += 4;
				PUGI_IMPL_SCANFOR(s[0] == '-' && s[1] == '-' && s[2] == '>'); // no need for ENDSWITH because --> can't terminate proper doctype
				if (!*s) PUGI_IMPL_THROW_ERROR(status_bad_doctype, s);

				s += 3;
			}
			else PUGI_IMPL_THROW_ERROR(status_bad_doctype, s);

			return s;
		}

		char_t* parse_doctype_ignore(char_t* s)
		{
			size_t depth = 0;

			assert(s[0] == '<' && s[1] == '!' && s[2] == '[');
			s += 3;

			while (*s)
			{
				if (s[0] == '<' && s[1] == '!' && s[2] == '[')
				{
					// nested ignore section
					s += 3;
					depth++;
				}
				else if (s[0] == ']' && s[1] == ']' && s[2] == '>')
				{
					// ignore section end
					s += 3;

					if (depth == 0)
						return s;

					depth--;
				}
				else s++;
			}

			PUGI_IMPL_THROW_ERROR(status_bad_doctype, s);
		}

		char_t* parse_doctype_group(char_t* s, char_t endch)
		{
			size_t depth = 0;

			assert((s[0] == '<' || s[0] == 0) && s[1] == '!');
			s += 2;

			while (*s)
			{
				if (s[0] == '<' && s[1] == '!' && s[2] != '-')
				{
					if (s[2] == '[')
					{
						// ignore
						s = parse_doctype_ignore(s);
						if (!s) return s;
					}
					else
					{
						// some control group
						s += 2;
						depth++;
					}
				}
				else if (s[0] == '<' || s[0] == '"' || s[0] == '\'')
				{
					// unknown tag (forbidden), or some primitive group
					s = parse_doctype_primitive(s);
					if (!s) return s;
				}
				else if (*s == '>')
				{
					if (depth == 0)
						return s;

					depth--;
					s++;
				}
				else s++;
			}

			if (depth != 0 || endch != '>') PUGI_IMPL_THROW_ERROR(status_bad_doctype, s);

			return s;
		}

		char_t* parse_exclamation(char_t* s, xml_node_struct* cursor, unsigned int optmsk, char_t endch)
		{
			// parse node contents, starting with exclamation mark
			++s;

			if (*s == '-') // '<!-...'
			{
				++s;

				if (*s == '-') // '<!--...'
				{
					++s;

					if (PUGI_IMPL_OPTSET(parse_comments))
					{
						PUGI_IMPL_PUSHNODE(node_comment); // Append a new node on the tree.
						cursor->value = s; // Save the offset.
					}

					if (PUGI_IMPL_OPTSET(parse_eol) && PUGI_IMPL_OPTSET(parse_comments))
					{
						s = strconv_comment(s, endch);

						if (!s) PUGI_IMPL_THROW_ERROR(status_bad_comment, cursor->value);
					}
					else
					{
						// Scan for terminating '-->'.
						PUGI_IMPL_SCANFOR(s[0] == '-' && s[1] == '-' && PUGI_IMPL_ENDSWITH(s[2], '>'));
						PUGI_IMPL_CHECK_ERROR(status_bad_comment, s);

						if (PUGI_IMPL_OPTSET(parse_comments))
							*s = 0; // Zero-terminate this segment at the first terminating '-'.

						s += (s[2] == '>' ? 3 : 2); // Step over the '\0->'.
					}
				}
				else PUGI_IMPL_THROW_ERROR(status_bad_comment, s);
			}
			else if (*s == '[')
			{
				// '<![CDATA[...'
				if (*++s=='C' && *++s=='D' && *++s=='A' && *++s=='T' && *++s=='A' && *++s == '[')
				{
					++s;

					if (PUGI_IMPL_OPTSET(parse_cdata))
					{
						PUGI_IMPL_PUSHNODE(node_cdata); // Append a new node on the tree.
						cursor->value = s; // Save the offset.

						if (PUGI_IMPL_OPTSET(parse_eol))
						{
							s = strconv_cdata(s, endch);

							if (!s) PUGI_IMPL_THROW_ERROR(status_bad_cdata, cursor->value);
						}
						else
						{
							// Scan for terminating ']]>'.
							PUGI_IMPL_SCANFOR(s[0] == ']' && s[1] == ']' && PUGI_IMPL_ENDSWITH(s[2], '>'));
							PUGI_IMPL_CHECK_ERROR(status_bad_cdata, s);

							*s++ = 0; // Zero-terminate this segment.
						}
					}
					else // Flagged for discard, but we still have to scan for the terminator.
					{
						// Scan for terminating ']]>'.
						PUGI_IMPL_SCANFOR(s[0] == ']' && s[1] == ']' && PUGI_IMPL_ENDSWITH(s[2], '>'));
						PUGI_IMPL_CHECK_ERROR(status_bad_cdata, s);

						++s;
					}

					s += (s[1] == '>' ? 2 : 1); // Step over the last ']>'.
				}
				else PUGI_IMPL_THROW_ERROR(status_bad_cdata, s);
			}
			else if (s[0] == 'D' && s[1] == 'O' && s[2] == 'C' && s[3] == 'T' && s[4] == 'Y' && s[5] == 'P' && PUGI_IMPL_ENDSWITH(s[6], 'E'))
			{
				s -= 2;

				if (cursor->parent) PUGI_IMPL_THROW_ERROR(status_bad_doctype, s);

				char_t* mark = s + 9;

				s = parse_doctype_group(s, endch);
				if (!s) return s;

				assert((*s == 0 && endch == '>') || *s == '>');
				if (*s) *s++ = 0;

				if (PUGI_IMPL_OPTSET(parse_doctype))
				{
					while (PUGI_IMPL_IS_CHARTYPE(*mark, ct_space)) ++mark;

					PUGI_IMPL_PUSHNODE(node_doctype);

					cursor->value = mark;
				}
			}
			else if (*s == 0 && endch == '-') PUGI_IMPL_THROW_ERROR(status_bad_comment, s);
			else if (*s == 0 && endch == '[') PUGI_IMPL_THROW_ERROR(status_bad_cdata, s);
			else PUGI_IMPL_THROW_ERROR(status_unrecognized_tag, s);

			return s;
		}

		char_t* parse_question(char_t* s, xml_node_struct*& ref_cursor, unsigned int optmsk, char_t endch)
		{
			// load into registers
			xml_node_struct* cursor = ref_cursor;
			char_t ch = 0;

			// parse node contents, starting with question mark
			++s;

			// read PI target
			char_t* target = s;

			if (!PUGI_IMPL_IS_CHARTYPE(*s, ct_start_symbol)) PUGI_IMPL_THROW_ERROR(status_bad_pi, s);

			PUGI_IMPL_SCANWHILE(PUGI_IMPL_IS_CHARTYPE(*s, ct_symbol));
			PUGI_IMPL_CHECK_ERROR(status_bad_pi, s);

			// determine node type; stricmp / strcasecmp is not portable
			bool declaration = (target[0] | ' ') == 'x' && (target[1] | ' ') == 'm' && (target[2] | ' ') == 'l' && target + 3 == s;

			if (declaration ? PUGI_IMPL_OPTSET(parse_declaration) : PUGI_IMPL_OPTSET(parse_pi))
			{
				if (declaration)
				{
					// disallow non top-level declarations
					if (cursor->parent) PUGI_IMPL_THROW_ERROR(status_bad_pi, s);

					PUGI_IMPL_PUSHNODE(node_declaration);
				}
				else
				{
					PUGI_IMPL_PUSHNODE(node_pi);
				}

				cursor->name = target;

				PUGI_IMPL_ENDSEG();

				// parse value/attributes
				if (ch == '?')
				{
					// empty node
					if (!PUGI_IMPL_ENDSWITH(*s, '>')) PUGI_IMPL_THROW_ERROR(status_bad_pi, s);
					s += (*s == '>');

					PUGI_IMPL_POPNODE();
				}
				else if (PUGI_IMPL_IS_CHARTYPE(ch, ct_space))
				{
					PUGI_IMPL_SKIPWS();

					// scan for tag end
					char_t* value = s;

					PUGI_IMPL_SCANFOR(s[0] == '?' && PUGI_IMPL_ENDSWITH(s[1], '>'));
					PUGI_IMPL_CHECK_ERROR(status_bad_pi, s);

					if (declaration)
					{
						// replace ending ? with / so that 'element' terminates properly
						*s = '/';

						// we exit from this function with cursor at node_declaration, which is a signal to parse() to go to LOC_ATTRIBUTES
						s = value;
					}
					else
					{
						// store value and step over >
						cursor->value = value;

						PUGI_IMPL_POPNODE();

						PUGI_IMPL_ENDSEG();

						s += (*s == '>');
					}
				}
				else PUGI_IMPL_THROW_ERROR(status_bad_pi, s);
			}
			else
			{
				// scan for tag end
				PUGI_IMPL_SCANFOR(s[0] == '?' && PUGI_IMPL_ENDSWITH(s[1], '>'));
				PUGI_IMPL_CHECK_ERROR(status_bad_pi, s);

				s += (s[1] == '>' ? 2 : 1);
			}

			// store from registers
			ref_cursor = cursor;

			return s;
		}

		char_t* parse_tree(char_t* s, xml_node_struct* root, unsigned int optmsk, char_t endch)
		{
			strconv_attribute_t strconv_attribute = get_strconv_attribute(optmsk);
			strconv_pcdata_t strconv_pcdata = get_strconv_pcdata(optmsk);

			char_t ch = 0;
			xml_node_struct* cursor = root;
			char_t* mark = s;
			char_t* merged_pcdata = s;

			while (*s != 0)
			{
				if (*s == '<')
				{
					++s;

				LOC_TAG:
					if (PUGI_IMPL_IS_CHARTYPE(*s, ct_start_symbol)) // '<#...'
					{
						PUGI_IMPL_PUSHNODE(node_element); // Append a new node to the tree.

						cursor->name = s;

						PUGI_IMPL_SCANWHILE_UNROLL(PUGI_IMPL_IS_CHARTYPE(ss, ct_symbol)); // Scan for a terminator.
						PUGI_IMPL_ENDSEG(); // Save char in 'ch', terminate & step over.

						if (ch == '>')
						{
							// end of tag
						}
						else if (PUGI_IMPL_IS_CHARTYPE(ch, ct_space))
						{
						LOC_ATTRIBUTES:
							while (true)
							{
								PUGI_IMPL_SKIPWS(); // Eat any whitespace.

								if (PUGI_IMPL_IS_CHARTYPE(*s, ct_start_symbol)) // <... #...
								{
									xml_attribute_struct* a = append_new_attribute(cursor, *alloc); // Make space for this attribute.
									if (!a) PUGI_IMPL_THROW_ERROR(status_out_of_memory, s);

									a->name = s; // Save the offset.

									PUGI_IMPL_SCANWHILE_UNROLL(PUGI_IMPL_IS_CHARTYPE(ss, ct_symbol)); // Scan for a terminator.
									PUGI_IMPL_ENDSEG(); // Save char in 'ch', terminate & step over.

									if (PUGI_IMPL_IS_CHARTYPE(ch, ct_space))
									{
										PUGI_IMPL_SKIPWS(); // Eat any whitespace.

										ch = *s;
										++s;
									}

									if (ch == '=') // '<... #=...'
									{
										PUGI_IMPL_SKIPWS(); // Eat any whitespace.

										if (*s == '"' || *s == '\'') // '<... #="...'
										{
											ch = *s; // Save quote char to avoid breaking on "''" -or- '""'.
											++s; // Step over the quote.
											a->value = s; // Save the offset.

											s = strconv_attribute(s, ch);

											if (!s) PUGI_IMPL_THROW_ERROR(status_bad_attribute, a->value);

											// After this line the loop continues from the start;
											// Whitespaces, / and > are ok, symbols and EOF are wrong,
											// everything else will be detected
											if (PUGI_IMPL_IS_CHARTYPE(*s, ct_start_symbol)) PUGI_IMPL_THROW_ERROR(status_bad_attribute, s);
										}
										else PUGI_IMPL_THROW_ERROR(status_bad_attribute, s);
									}
									else PUGI_IMPL_THROW_ERROR(status_bad_attribute, s);
								}
								else if (*s == '/')
								{
									++s;

									if (*s == '>')
									{
										PUGI_IMPL_POPNODE();
										s++;
										break;
									}
									else if (*s == 0 && endch == '>')
									{
										PUGI_IMPL_POPNODE();
										break;
									}
									else PUGI_IMPL_THROW_ERROR(status_bad_start_element, s);
								}
								else if (*s == '>')
								{
									++s;

									break;
								}
								else if (*s == 0 && endch == '>')
								{
									break;
								}
								else PUGI_IMPL_THROW_ERROR(status_bad_start_element, s);
							}

							// !!!
						}
						else if (ch == '/') // '<#.../'
						{
							if (!PUGI_IMPL_ENDSWITH(*s, '>')) PUGI_IMPL_THROW_ERROR(status_bad_start_element, s);

							PUGI_IMPL_POPNODE(); // Pop.

							s += (*s == '>');
						}
						else if (ch == 0)
						{
							// we stepped over null terminator, backtrack & handle closing tag
							--s;

							if (endch != '>') PUGI_IMPL_THROW_ERROR(status_bad_start_element, s);
						}
						else PUGI_IMPL_THROW_ERROR(status_bad_start_element, s);
					}
					else if (*s == '/')
					{
						++s;

						mark = s;

						char_t* name = cursor->name;
						if (!name) PUGI_IMPL_THROW_ERROR(status_end_element_mismatch, mark);

						while (PUGI_IMPL_IS_CHARTYPE(*s, ct_symbol))
						{
							if (*s++ != *name++) PUGI_IMPL_THROW_ERROR(status_end_element_mismatch, mark);
						}

						if (*name)
						{
							if (*s == 0 && name[0] == endch && name[1] == 0) PUGI_IMPL_THROW_ERROR(status_bad_end_element, s);
							else PUGI_IMPL_THROW_ERROR(status_end_element_mismatch, mark);
						}

						PUGI_IMPL_POPNODE(); // Pop.

						PUGI_IMPL_SKIPWS();

						if (*s == 0)
						{
							if (endch != '>') PUGI_IMPL_THROW_ERROR(status_bad_end_element, s);
						}
						else
						{
							if (*s != '>') PUGI_IMPL_THROW_ERROR(status_bad_end_element, s);
							++s;
						}
					}
					else if (*s == '?') // '<?...'
					{
						s = parse_question(s, cursor, optmsk, endch);
						if (!s) return s;

						assert(cursor);
						if (PUGI_IMPL_NODETYPE(cursor) == node_declaration) goto LOC_ATTRIBUTES;
					}
					else if (*s == '!') // '<!...'
					{
						s = parse_exclamation(s, cursor, optmsk, endch);
						if (!s) return s;
					}
					else if (*s == 0 && endch == '?') PUGI_IMPL_THROW_ERROR(status_bad_pi, s);
					else PUGI_IMPL_THROW_ERROR(status_unrecognized_tag, s);
				}
				else
				{
					mark = s; // Save this offset while searching for a terminator.

					PUGI_IMPL_SKIPWS(); // Eat whitespace if no genuine PCDATA here.

					if (*s == '<' || !*s)
					{
						// We skipped some whitespace characters because otherwise we would take the tag branch instead of PCDATA one
						assert(mark != s);

						if (!PUGI_IMPL_OPTSET(parse_ws_pcdata | parse_ws_pcdata_single) || PUGI_IMPL_OPTSET(parse_trim_pcdata))
						{
							continue;
						}
						else if (PUGI_IMPL_OPTSET(parse_ws_pcdata_single))
						{
							if (s[0] != '<' || s[1] != '/' || cursor->first_child) continue;
						}
					}

					if (!PUGI_IMPL_OPTSET(parse_trim_pcdata))
						s = mark;

					if (cursor->parent || PUGI_IMPL_OPTSET(parse_fragment))
					{
						char_t* parsed_pcdata = s;

						s = strconv_pcdata(s);

						if (PUGI_IMPL_OPTSET(parse_embed_pcdata) && cursor->parent && !cursor->first_child && !cursor->value)
						{
							cursor->value = parsed_pcdata; // Save the offset.
						}
						else if (PUGI_IMPL_OPTSET(parse_merge_pcdata) && cursor->first_child && PUGI_IMPL_NODETYPE(cursor->first_child->prev_sibling_c) == node_pcdata)
						{
							assert(merged_pcdata >= cursor->first_child->prev_sibling_c->value);

							// Catch up to the end of last parsed value; only needed for the first fragment.
							merged_pcdata += strlength(merged_pcdata);

							size_t length = strlength(parsed_pcdata);

							// Must use memmove instead of memcpy as this move may overlap
							memmove(merged_pcdata, parsed_pcdata, (length + 1) * sizeof(char_t));
							merged_pcdata += length;
						}
						else
						{
							xml_node_struct* prev_cursor = cursor;
							PUGI_IMPL_PUSHNODE(node_pcdata); // Append a new node on the tree.

							cursor->value = parsed_pcdata; // Save the offset.
							merged_pcdata = parsed_pcdata; // Used for parse_merge_pcdata above, cheaper to save unconditionally

							cursor = prev_cursor; // Pop since this is a standalone.
						}

						if (!*s) break;
					}
					else
					{
						PUGI_IMPL_SCANFOR(*s == '<'); // '...<'
						if (!*s) break;

						++s;
					}

					// We're after '<'
					goto LOC_TAG;
				}
			}

			// check that last tag is closed
			if (cursor != root) PUGI_IMPL_THROW_ERROR(status_end_element_mismatch, s);

			return s;
		}

	#ifdef PUGIXML_WCHAR_MODE
		static char_t* parse_skip_bom(char_t* s)
		{
			unsigned int bom = 0xfeff;
			return (s[0] == static_cast<wchar_t>(bom)) ? s + 1 : s;
		}
	#else
		static char_t* parse_skip_bom(char_t* s)
		{
			return (s[0] == '\xef' && s[1] == '\xbb' && s[2] == '\xbf') ? s + 3 : s;
		}
	#endif

		static bool has_element_node_siblings(xml_node_struct* node)
		{
			while (node)
			{
				if (PUGI_IMPL_NODETYPE(node) == node_element) return true;

				node = node->next_sibling;
			}

			return false;
		}

		static xml_parse_result parse(char_t* buffer, size_t length, xml_document_struct* xmldoc, xml_node_struct* root, unsigned int optmsk)
		{
			// early-out for empty documents
			if (length == 0)
				return make_parse_result(PUGI_IMPL_OPTSET(parse_fragment) ? status_ok : status_no_document_element);

			// get last child of the root before parsing
			xml_node_struct* last_root_child = root->first_child ? root->first_child->prev_sibling_c + 0 : 0;

			// create parser on stack
			xml_parser parser(static_cast<xml_allocator*>(xmldoc));

			// save last character and make buffer zero-terminated (speeds up parsing)
			char_t endch = buffer[length - 1];
			buffer[length - 1] = 0;

			// skip BOM to make sure it does not end up as part of parse output
			char_t* buffer_data = parse_skip_bom(buffer);

			// perform actual parsing
			parser.parse_tree(buffer_data, root, optmsk, endch);

			xml_parse_result result = make_parse_result(parser.error_status, parser.error_offset ? parser.error_offset - buffer : 0);
			assert(result.offset >= 0 && static_cast<size_t>(result.offset) <= length);

			if (result)
			{
				// since we removed last character, we have to handle the only possible false positive (stray <)
				if (endch == '<')
					return make_parse_result(status_unrecognized_tag, length - 1);

				// check if there are any element nodes parsed
				xml_node_struct* first_root_child_parsed = last_root_child ? last_root_child->next_sibling + 0 : root->first_child + 0;

				if (!PUGI_IMPL_OPTSET(parse_fragment) && !has_element_node_siblings(first_root_child_parsed))
					return make_parse_result(status_no_document_element, length - 1);
			}
			else
			{
				// roll back offset if it occurs on a null terminator in the source buffer
				if (result.offset > 0 && static_cast<size_t>(result.offset) == length - 1 && endch == 0)
					result.offset--;
			}

			return result;
		}
	};

	// Output facilities
	PUGI_IMPL_FN xml_encoding get_write_native_encoding()
	{
	#ifdef PUGIXML_WCHAR_MODE
		return get_wchar_encoding();
	#else
		return encoding_utf8;
	#endif
	}

	PUGI_IMPL_FN xml_encoding get_write_encoding(xml_encoding encoding)
	{
		// replace wchar encoding with utf implementation
		if (encoding == encoding_wchar) return get_wchar_encoding();

		// replace utf16 encoding with utf16 with specific endianness
		if (encoding == encoding_utf16) return is_little_endian() ? encoding_utf16_le : encoding_utf16_be;

		// replace utf32 encoding with utf32 with specific endianness
		if (encoding == encoding_utf32) return is_little_endian() ? encoding_utf32_le : encoding_utf32_be;

		// only do autodetection if no explicit encoding is requested
		if (encoding != encoding_auto) return encoding;

		// assume utf8 encoding
		return encoding_utf8;
	}

	template <typename D, typename T> PUGI_IMPL_FN size_t convert_buffer_output_generic(typename T::value_type dest, const char_t* data, size_t length, D, T)
	{
		PUGI_IMPL_STATIC_ASSERT(sizeof(char_t) == sizeof(typename D::type));

		typename T::value_type end = D::process(reinterpret_cast<const typename D::type*>(data), length, dest, T());

		return static_cast<size_t>(end - dest) * sizeof(*dest);
	}

	template <typename D, typename T> PUGI_IMPL_FN size_t convert_buffer_output_generic(typename T::value_type dest, const char_t* data, size_t length, D, T, bool opt_swap)
	{
		PUGI_IMPL_STATIC_ASSERT(sizeof(char_t) == sizeof(typename D::type));

		typename T::value_type end = D::process(reinterpret_cast<const typename D::type*>(data), length, dest, T());

		if (opt_swap)
		{
			for (typename T::value_type i = dest; i != end; ++i)
				*i = endian_swap(*i);
		}

		return static_cast<size_t>(end - dest) * sizeof(*dest);
	}

#ifdef PUGIXML_WCHAR_MODE
	PUGI_IMPL_FN size_t get_valid_length(const char_t* data, size_t length)
	{
		if (length < 1) return 0;

		// discard last character if it's the lead of a surrogate pair
		return (sizeof(wchar_t) == 2 && static_cast<unsigned int>(static_cast<uint16_t>(data[length - 1]) - 0xD800) < 0x400) ? length - 1 : length;
	}

	PUGI_IMPL_FN size_t convert_buffer_output(char_t* r_char, uint8_t* r_u8, uint16_t* r_u16, uint32_t* r_u32, const char_t* data, size_t length, xml_encoding encoding)
	{
		// only endian-swapping is required
		if (need_endian_swap_utf(encoding, get_wchar_encoding()))
		{
			convert_wchar_endian_swap(r_char, data, length);

			return length * sizeof(char_t);
		}

		// convert to utf8
		if (encoding == encoding_utf8)
			return convert_buffer_output_generic(r_u8, data, length, wchar_decoder(), utf8_writer());

		// convert to utf16
		if (encoding == encoding_utf16_be || encoding == encoding_utf16_le)
		{
			xml_encoding native_encoding = is_little_endian() ? encoding_utf16_le : encoding_utf16_be;

			return convert_buffer_output_generic(r_u16, data, length, wchar_decoder(), utf16_writer(), native_encoding != encoding);
		}

		// convert to utf32
		if (encoding == encoding_utf32_be || encoding == encoding_utf32_le)
		{
			xml_encoding native_encoding = is_little_endian() ? encoding_utf32_le : encoding_utf32_be;

			return convert_buffer_output_generic(r_u32, data, length, wchar_decoder(), utf32_writer(), native_encoding != encoding);
		}

		// convert to latin1
		if (encoding == encoding_latin1)
			return convert_buffer_output_generic(r_u8, data, length, wchar_decoder(), latin1_writer());

		assert(false && "Invalid encoding"); // unreachable
		return 0;
	}
#else
	PUGI_IMPL_FN size_t get_valid_length(const char_t* data, size_t length)
	{
		if (length < 5) return 0;

		for (size_t i = 1; i <= 4; ++i)
		{
			uint8_t ch = static_cast<uint8_t>(data[length - i]);

			// either a standalone character or a leading one
			if ((ch & 0xc0) != 0x80) return length - i;
		}

		// there are four non-leading characters at the end, sequence tail is broken so might as well process the whole chunk
		return length;
	}

	PUGI_IMPL_FN size_t convert_buffer_output(char_t* /* r_char */, uint8_t* r_u8, uint16_t* r_u16, uint32_t* r_u32, const char_t* data, size_t length, xml_encoding encoding)
	{
		if (encoding == encoding_utf16_be || encoding == encoding_utf16_le)
		{
			xml_encoding native_encoding = is_little_endian() ? encoding_utf16_le : encoding_utf16_be;

			return convert_buffer_output_generic(r_u16, data, length, utf8_decoder(), utf16_writer(), native_encoding != encoding);
		}

		if (encoding == encoding_utf32_be || encoding == encoding_utf32_le)
		{
			xml_encoding native_encoding = is_little_endian() ? encoding_utf32_le : encoding_utf32_be;

			return convert_buffer_output_generic(r_u32, data, length, utf8_decoder(), utf32_writer(), native_encoding != encoding);
		}

		if (encoding == encoding_latin1)
			return convert_buffer_output_generic(r_u8, data, length, utf8_decoder(), latin1_writer());

		assert(false && "Invalid encoding"); // unreachable
		return 0;
	}
#endif

	class xml_buffered_writer
	{
		xml_buffered_writer(const xml_buffered_writer&);
		xml_buffered_writer& operator=(const xml_buffered_writer&);

	public:
		xml_buffered_writer(xml_writer& writer_, xml_encoding user_encoding): writer(writer_), bufsize(0), encoding(get_write_encoding(user_encoding))
		{
			PUGI_IMPL_STATIC_ASSERT(bufcapacity >= 8);
		}

		size_t flush()
		{
			flush(buffer, bufsize);
			bufsize = 0;
			return 0;
		}

		void flush(const char_t* data, size_t size)
		{
			if (size == 0) return;

			// fast path, just write data
			if (encoding == get_write_native_encoding())
				writer.write(data, size * sizeof(char_t));
			else
			{
				// convert chunk
				size_t result = convert_buffer_output(scratch.data_char, scratch.data_u8, scratch.data_u16, scratch.data_u32, data, size, encoding);
				assert(result <= sizeof(scratch));

				// write data
				writer.write(scratch.data_u8, result);
			}
		}

		void write_direct(const char_t* data, size_t length)
		{
			// flush the remaining buffer contents
			flush();

			// handle large chunks
			if (length > bufcapacity)
			{
				if (encoding == get_write_native_encoding())
				{
					// fast path, can just write data chunk
					writer.write(data, length * sizeof(char_t));
					return;
				}

				// need to convert in suitable chunks
				while (length > bufcapacity)
				{
					// get chunk size by selecting such number of characters that are guaranteed to fit into scratch buffer
					// and form a complete codepoint sequence (i.e. discard start of last codepoint if necessary)
					size_t chunk_size = get_valid_length(data, bufcapacity);
					assert(chunk_size);

					// convert chunk and write
					flush(data, chunk_size);

					// iterate
					data += chunk_size;
					length -= chunk_size;
				}

				// small tail is copied below
				bufsize = 0;
			}

			memcpy(buffer + bufsize, data, length * sizeof(char_t));
			bufsize += length;
		}

		void write_buffer(const char_t* data, size_t length)
		{
			size_t offset = bufsize;

			if (offset + length <= bufcapacity)
			{
				memcpy(buffer + offset, data, length * sizeof(char_t));
				bufsize = offset + length;
			}
			else
			{
				write_direct(data, length);
			}
		}

		void write_string(const char_t* data)
		{
			// write the part of the string that fits in the buffer
			size_t offset = bufsize;

			while (*data && offset < bufcapacity)
				buffer[offset++] = *data++;

			// write the rest
			if (offset < bufcapacity)
			{
				bufsize = offset;
			}
			else
			{
				// backtrack a bit if we have split the codepoint
				size_t length = offset - bufsize;
				size_t extra = length - get_valid_length(data - length, length);

				bufsize = offset - extra;

				write_direct(data - extra, strlength(data) + extra);
			}
		}

		void write(char_t d0)
		{
			size_t offset = bufsize;
			if (offset > bufcapacity - 1) offset = flush();

			buffer[offset + 0] = d0;
			bufsize = offset + 1;
		}

		void write(char_t d0, char_t d1)
		{
			size_t offset = bufsize;
			if (offset > bufcapacity - 2) offset = flush();

			buffer[offset + 0] = d0;
			buffer[offset + 1] = d1;
			bufsize = offset + 2;
		}

		void write(char_t d0, char_t d1, char_t d2)
		{
			size_t offset = bufsize;
			if (offset > bufcapacity - 3) offset = flush();

			buffer[offset + 0] = d0;
			buffer[offset + 1] = d1;
			buffer[offset + 2] = d2;
			bufsize = offset + 3;
		}

		void write(char_t d0, char_t d1, char_t d2, char_t d3)
		{
			size_t offset = bufsize;
			if (offset > bufcapacity - 4) offset = flush();

			buffer[offset + 0] = d0;
			buffer[offset + 1] = d1;
			buffer[offset + 2] = d2;
			buffer[offset + 3] = d3;
			bufsize = offset + 4;
		}

		void write(char_t d0, char_t d1, char_t d2, char_t d3, char_t d4)
		{
			size_t offset = bufsize;
			if (offset > bufcapacity - 5) offset = flush();

			buffer[offset + 0] = d0;
			buffer[offset + 1] = d1;
			buffer[offset + 2] = d2;
			buffer[offset + 3] = d3;
			buffer[offset + 4] = d4;
			bufsize = offset + 5;
		}

		void write(char_t d0, char_t d1, char_t d2, char_t d3, char_t d4, char_t d5)
		{
			size_t offset = bufsize;
			if (offset > bufcapacity - 6) offset = flush();

			buffer[offset + 0] = d0;
			buffer[offset + 1] = d1;
			buffer[offset + 2] = d2;
			buffer[offset + 3] = d3;
			buffer[offset + 4] = d4;
			buffer[offset + 5] = d5;
			bufsize = offset + 6;
		}

		// utf8 maximum expansion: x4 (-> utf32)
		// utf16 maximum expansion: x2 (-> utf32)
		// utf32 maximum expansion: x1
		enum
		{
			bufcapacitybytes =
			#ifdef PUGIXML_MEMORY_OUTPUT_STACK
				PUGIXML_MEMORY_OUTPUT_STACK
			#else
				10240
			#endif
			,
			bufcapacity = bufcapacitybytes / (sizeof(char_t) + 4)
		};

		char_t buffer[bufcapacity];

		union
		{
			uint8_t data_u8[4 * bufcapacity];
			uint16_t data_u16[2 * bufcapacity];
			uint32_t data_u32[bufcapacity];
			char_t data_char[bufcapacity];
		} scratch;

		xml_writer& writer;
		size_t bufsize;
		xml_encoding encoding;
	};

	PUGI_IMPL_FN void text_output_escaped(xml_buffered_writer& writer, const char_t* s, chartypex_t type, unsigned int flags)
	{
		while (*s)
		{
			const char_t* prev = s;

			// While *s is a usual symbol
			PUGI_IMPL_SCANWHILE_UNROLL(!PUGI_IMPL_IS_CHARTYPEX(ss, type));

			writer.write_buffer(prev, static_cast<size_t>(s - prev));

			switch (*s)
			{
				case 0: break;
				case '&':
					writer.write('&', 'a', 'm', 'p', ';');
					++s;
					break;
				case '<':
					writer.write('&', 'l', 't', ';');
					++s;
					break;
				case '>':
					writer.write('&', 'g', 't', ';');
					++s;
					break;
				case '"':
					if (flags & format_attribute_single_quote)
						writer.write('"');
					else
						writer.write('&', 'q', 'u', 'o', 't', ';');
					++s;
					break;
				case '\'':
					if (flags & format_attribute_single_quote)
						writer.write('&', 'a', 'p', 'o', 's', ';');
					else
						writer.write('\'');
					++s;
					break;
				default: // s is not a usual symbol
				{
					unsigned int ch = static_cast<unsigned int>(*s++);
					assert(ch < 32);

					if (!(flags & format_skip_control_chars))
						writer.write('&', '#', static_cast<char_t>((ch / 10) + '0'), static_cast<char_t>((ch % 10) + '0'), ';');
				}
			}
		}
	}

	PUGI_IMPL_FN void text_output(xml_buffered_writer& writer, const char_t* s, chartypex_t type, unsigned int flags)
	{
		if (flags & format_no_escapes)
			writer.write_string(s);
		else
			text_output_escaped(writer, s, type, flags);
	}

	PUGI_IMPL_FN void text_output_cdata(xml_buffered_writer& writer, const char_t* s)
	{
		do
		{
			writer.write('<', '!', '[', 'C', 'D');
			writer.write('A', 'T', 'A', '[');

			const char_t* prev = s;

			// look for ]]> sequence - we can't output it as is since it terminates CDATA
			while (*s && !(s[0] == ']' && s[1] == ']' && s[2] == '>')) ++s;

			// skip ]] if we stopped at ]]>, > will go to the next CDATA section
			if (*s) s += 2;

			writer.write_buffer(prev, static_cast<size_t>(s - prev));

			writer.write(']', ']', '>');
		}
		while (*s);
	}

	PUGI_IMPL_FN void text_output_indent(xml_buffered_writer& writer, const char_t* indent, size_t indent_length, unsigned int depth)
	{
		switch (indent_length)
		{
		case 1:
		{
			for (unsigned int i = 0; i < depth; ++i)
				writer.write(indent[0]);
			break;
		}

		case 2:
		{
			for (unsigned int i = 0; i < depth; ++i)
				writer.write(indent[0], indent[1]);
			break;
		}

		case 3:
		{
			for (unsigned int i = 0; i < depth; ++i)
				writer.write(indent[0], indent[1], indent[2]);
			break;
		}

		case 4:
		{
			for (unsigned int i = 0; i < depth; ++i)
				writer.write(indent[0], indent[1], indent[2], indent[3]);
			break;
		}

		default:
		{
			for (unsigned int i = 0; i < depth; ++i)
				writer.write_buffer(indent, indent_length);
		}
		}
	}

	PUGI_IMPL_FN void node_output_comment(xml_buffered_writer& writer, const char_t* s)
	{
		writer.write('<', '!', '-', '-');

		while (*s)
		{
			const char_t* prev = s;

			// look for -\0 or -- sequence - we can't output it since -- is illegal in comment body
			while (*s && !(s[0] == '-' && (s[1] == '-' || s[1] == 0))) ++s;

			writer.write_buffer(prev, static_cast<size_t>(s - prev));

			if (*s)
			{
				assert(*s == '-');

				writer.write('-', ' ');
				++s;
			}
		}

		writer.write('-', '-', '>');
	}

	PUGI_IMPL_FN void node_output_pi_value(xml_buffered_writer& writer, const char_t* s)
	{
		while (*s)
		{
			const char_t* prev = s;

			// look for ?> sequence - we can't output it since ?> terminates PI
			while (*s && !(s[0] == '?' && s[1] == '>')) ++s;

			writer.write_buffer(prev, static_cast<size_t>(s - prev));

			if (*s)
			{
				assert(s[0] == '?' && s[1] == '>');

				writer.write('?', ' ', '>');
				s += 2;
			}
		}
	}

	PUGI_IMPL_FN void node_output_attributes(xml_buffered_writer& writer, xml_node_struct* node, const char_t* indent, size_t indent_length, unsigned int flags, unsigned int depth)
	{
		const char_t* default_name = PUGIXML_TEXT(":anonymous");
		const char_t enquotation_char = (flags & format_attribute_single_quote) ? '\'' : '"';

		for (xml_attribute_struct* a = node->first_attribute; a; a = a->next_attribute)
		{
			if ((flags & (format_indent_attributes | format_raw)) == format_indent_attributes)
			{
				writer.write('\n');

				text_output_indent(writer, indent, indent_length, depth + 1);
			}
			else
			{
				writer.write(' ');
			}

			writer.write_string(a->name ? a->name + 0 : default_name);
			writer.write('=', enquotation_char);

			if (a->value)
				text_output(writer, a->value, ctx_special_attr, flags);

			writer.write(enquotation_char);
		}
	}

	PUGI_IMPL_FN bool node_output_start(xml_buffered_writer& writer, xml_node_struct* node, const char_t* indent, size_t indent_length, unsigned int flags, unsigned int depth)
	{
		const char_t* default_name = PUGIXML_TEXT(":anonymous");
		const char_t* name = node->name ? node->name + 0 : default_name;

		writer.write('<');
		writer.write_string(name);

		if (node->first_attribute)
			node_output_attributes(writer, node, indent, indent_length, flags, depth);

		// element nodes can have value if parse_embed_pcdata was used
		if (!node->value)
		{
			if (!node->first_child)
			{
				if (flags & format_no_empty_element_tags)
				{
					writer.write('>', '<', '/');
					writer.write_string(name);
					writer.write('>');

					return false;
				}
				else
				{
					if ((flags & format_raw) == 0)
						writer.write(' ');

					writer.write('/', '>');

					return false;
				}
			}
			else
			{
				writer.write('>');

				return true;
			}
		}
		else
		{
			writer.write('>');

			text_output(writer, node->value, ctx_special_pcdata, flags);

			if (!node->first_child)
			{
				writer.write('<', '/');
				writer.write_string(name);
				writer.write('>');

				return false;
			}
			else
			{
				return true;
			}
		}
	}

	PUGI_IMPL_FN void node_output_end(xml_buffered_writer& writer, xml_node_struct* node)
	{
		const char_t* default_name = PUGIXML_TEXT(":anonymous");
		const char_t* name = node->name ? node->name + 0 : default_name;

		writer.write('<', '/');
		writer.write_string(name);
		writer.write('>');
	}

	PUGI_IMPL_FN void node_output_simple(xml_buffered_writer& writer, xml_node_struct* node, unsigned int flags)
	{
		const char_t* default_name = PUGIXML_TEXT(":anonymous");

		switch (PUGI_IMPL_NODETYPE(node))
		{
			case node_pcdata:
				text_output(writer, node->value ? node->value + 0 : PUGIXML_TEXT(""), ctx_special_pcdata, flags);
				break;

			case node_cdata:
				text_output_cdata(writer, node->value ? node->value + 0 : PUGIXML_TEXT(""));
				break;

			case node_comment:
				node_output_comment(writer, node->value ? node->value + 0 : PUGIXML_TEXT(""));
				break;

			case node_pi:
				writer.write('<', '?');
				writer.write_string(node->name ? node->name + 0 : default_name);

				if (node->value)
				{
					writer.write(' ');
					node_output_pi_value(writer, node->value);
				}

				writer.write('?', '>');
				break;

			case node_declaration:
				writer.write('<', '?');
				writer.write_string(node->name ? node->name + 0 : default_name);
				node_output_attributes(writer, node, PUGIXML_TEXT(""), 0, flags | format_raw, 0);
				writer.write('?', '>');
				break;

			case node_doctype:
				writer.write('<', '!', 'D', 'O', 'C');
				writer.write('T', 'Y', 'P', 'E');

				if (node->value)
				{
					writer.write(' ');
					writer.write_string(node->value);
				}

				writer.write('>');
				break;

			default:
				assert(false && "Invalid node type"); // unreachable
		}
	}

	enum indent_flags_t
	{
		indent_newline = 1,
		indent_indent = 2
	};

	PUGI_IMPL_FN void node_output(xml_buffered_writer& writer, xml_node_struct* root, const char_t* indent, unsigned int flags, unsigned int depth)
	{
		size_t indent_length = ((flags & (format_indent | format_indent_attributes)) && (flags & format_raw) == 0) ? strlength(indent) : 0;
		unsigned int indent_flags = indent_indent;

		xml_node_struct* node = root;

		do
		{
			assert(node);

			// begin writing current node
			if (PUGI_IMPL_NODETYPE(node) == node_pcdata || PUGI_IMPL_NODETYPE(node) == node_cdata)
			{
				node_output_simple(writer, node, flags);

				indent_flags = 0;
			}
			else
			{
				if ((indent_flags & indent_newline) && (flags & format_raw) == 0)
					writer.write('\n');

				if ((indent_flags & indent_indent) && indent_length)
					text_output_indent(writer, indent, indent_length, depth);

				if (PUGI_IMPL_NODETYPE(node) == node_element)
				{
					indent_flags = indent_newline | indent_indent;

					if (node_output_start(writer, node, indent, indent_length, flags, depth))
					{
						// element nodes can have value if parse_embed_pcdata was used
						if (node->value)
							indent_flags = 0;

						node = node->first_child;
						depth++;
						continue;
					}
				}
				else if (PUGI_IMPL_NODETYPE(node) == node_document)
				{
					indent_flags = indent_indent;

					if (node->first_child)
					{
						node = node->first_child;
						continue;
					}
				}
				else
				{
					node_output_simple(writer, node, flags);

					indent_flags = indent_newline | indent_indent;
				}
			}

			// continue to the next node
			while (node != root)
			{
				if (node->next_sibling)
				{
					node = node->next_sibling;
					break;
				}

				node = node->parent;

				// write closing node
				if (PUGI_IMPL_NODETYPE(node) == node_element)
				{
					depth--;

					if ((indent_flags & indent_newline) && (flags & format_raw) == 0)
						writer.write('\n');

					if ((indent_flags & indent_indent) && indent_length)
						text_output_indent(writer, indent, indent_length, depth);

					node_output_end(writer, node);

					indent_flags = indent_newline | indent_indent;
				}
			}
		}
		while (node != root);

		if ((indent_flags & indent_newline) && (flags & format_raw) == 0)
			writer.write('\n');
	}

	PUGI_IMPL_FN bool has_declaration(xml_node_struct* node)
	{
		for (xml_node_struct* child = node->first_child; child; child = child->next_sibling)
		{
			xml_node_type type = PUGI_IMPL_NODETYPE(child);

			if (type == node_declaration) return true;
			if (type == node_element) return false;
		}

		return false;
	}

	PUGI_IMPL_FN bool is_attribute_of(xml_attribute_struct* attr, xml_node_struct* node)
	{
		for (xml_attribute_struct* a = node->first_attribute; a; a = a->next_attribute)
			if (a == attr)
				return true;

		return false;
	}

	PUGI_IMPL_FN bool allow_insert_attribute(xml_node_type parent)
	{
		return parent == node_element || parent == node_declaration;
	}

	PUGI_IMPL_FN bool allow_insert_child(xml_node_type parent, xml_node_type child)
	{
		if (parent != node_document && parent != node_element) return false;
		if (child == node_document || child == node_null) return false;
		if (parent != node_document && (child == node_declaration || child == node_doctype)) return false;

		return true;
	}

	PUGI_IMPL_FN bool allow_move(xml_node parent, xml_node child)
	{
		// check that child can be a child of parent
		if (!allow_insert_child(parent.type(), child.type()))
			return false;

		// check that node is not moved between documents
		if (parent.root() != child.root())
			return false;

		// check that new parent is not in the child subtree
		xml_node cur = parent;

		while (cur)
		{
			if (cur == child)
				return false;

			cur = cur.parent();
		}

		return true;
	}

	template <typename String, typename Header>
	PUGI_IMPL_FN void node_copy_string(String& dest, Header& header, uintptr_t header_mask, char_t* source, Header& source_header, xml_allocator* alloc)
	{
		assert(!dest && (header & header_mask) == 0); // copies are performed into fresh nodes

		if (source)
		{
			if (alloc && (source_header & header_mask) == 0)
			{
				dest = source;

				// since strcpy_insitu can reuse document buffer memory we need to mark both source and dest as shared
				header |= xml_memory_page_contents_shared_mask;
				source_header |= xml_memory_page_contents_shared_mask;
			}
			else
				strcpy_insitu(dest, header, header_mask, source, strlength(source));
		}
	}

	PUGI_IMPL_FN void node_copy_contents(xml_node_struct* dn, xml_node_struct* sn, xml_allocator* shared_alloc)
	{
		node_copy_string(dn->name, dn->header, xml_memory_page_name_allocated_mask, sn->name, sn->header, shared_alloc);
		node_copy_string(dn->value, dn->header, xml_memory_page_value_allocated_mask, sn->value, sn->header, shared_alloc);

		for (xml_attribute_struct* sa = sn->first_attribute; sa; sa = sa->next_attribute)
		{
			xml_attribute_struct* da = append_new_attribute(dn, get_allocator(dn));

			if (da)
			{
				node_copy_string(da->name, da->header, xml_memory_page_name_allocated_mask, sa->name, sa->header, shared_alloc);
				node_copy_string(da->value, da->header, xml_memory_page_value_allocated_mask, sa->value, sa->header, shared_alloc);
			}
		}
	}

	PUGI_IMPL_FN void node_copy_tree(xml_node_struct* dn, xml_node_struct* sn)
	{
		xml_allocator& alloc = get_allocator(dn);
		xml_allocator* shared_alloc = (&alloc == &get_allocator(sn)) ? &alloc : 0;

		node_copy_contents(dn, sn, shared_alloc);

		xml_node_struct* dit = dn;
		xml_node_struct* sit = sn->first_child;

		while (sit && sit != sn)
		{
			// loop invariant: dit is inside the subtree rooted at dn
			assert(dit);

			// when a tree is copied into one of the descendants, we need to skip that subtree to avoid an infinite loop
			if (sit != dn)
			{
				xml_node_struct* copy = append_new_node(dit, alloc, PUGI_IMPL_NODETYPE(sit));

				if (copy)
				{
					node_copy_contents(copy, sit, shared_alloc);

					if (sit->first_child)
					{
						dit = copy;
						sit = sit->first_child;
						continue;
					}
				}
			}

			// continue to the next node
			do
			{
				if (sit->next_sibling)
				{
					sit = sit->next_sibling;
					break;
				}

				sit = sit->parent;
				dit = dit->parent;

				// loop invariant: dit is inside the subtree rooted at dn while sit is inside sn
				assert(sit == sn || dit);
			}
			while (sit != sn);
		}

		assert(!sit || dit == dn->parent);
	}

	PUGI_IMPL_FN void node_copy_attribute(xml_attribute_struct* da, xml_attribute_struct* sa)
	{
		xml_allocator& alloc = get_allocator(da);
		xml_allocator* shared_alloc = (&alloc == &get_allocator(sa)) ? &alloc : 0;

		node_copy_string(da->name, da->header, xml_memory_page_name_allocated_mask, sa->name, sa->header, shared_alloc);
		node_copy_string(da->value, da->header, xml_memory_page_value_allocated_mask, sa->value, sa->header, shared_alloc);
	}

	inline bool is_text_node(xml_node_struct* node)
	{
		xml_node_type type = PUGI_IMPL_NODETYPE(node);

		return type == node_pcdata || type == node_cdata;
	}

	// get value with conversion functions
	template <typename U> PUGI_IMPL_FN PUGI_IMPL_UNSIGNED_OVERFLOW U string_to_integer(const char_t* value, U minv, U maxv)
	{
		U result = 0;
		const char_t* s = value;

		while (PUGI_IMPL_IS_CHARTYPE(*s, ct_space))
			s++;

		bool negative = (*s == '-');

		s += (*s == '+' || *s == '-');

		bool overflow = false;

		if (s[0] == '0' && (s[1] | ' ') == 'x')
		{
			s += 2;

			// since overflow detection relies on length of the sequence skip leading zeros
			while (*s == '0')
				s++;

			const char_t* start = s;

			for (;;)
			{
				if (static_cast<unsigned>(*s - '0') < 10)
					result = result * 16 + (*s - '0');
				else if (static_cast<unsigned>((*s | ' ') - 'a') < 6)
					result = result * 16 + ((*s | ' ') - 'a' + 10);
				else
					break;

				s++;
			}

			size_t digits = static_cast<size_t>(s - start);

			overflow = digits > sizeof(U) * 2;
		}
		else
		{
			// since overflow detection relies on length of the sequence skip leading zeros
			while (*s == '0')
				s++;

			const char_t* start = s;

			for (;;)
			{
				if (static_cast<unsigned>(*s - '0') < 10)
					result = result * 10 + (*s - '0');
				else
					break;

				s++;
			}

			size_t digits = static_cast<size_t>(s - start);

			PUGI_IMPL_STATIC_ASSERT(sizeof(U) == 8 || sizeof(U) == 4 || sizeof(U) == 2);

			const size_t max_digits10 = sizeof(U) == 8 ? 20 : sizeof(U) == 4 ? 10 : 5;
			const char_t max_lead = sizeof(U) == 8 ? '1' : sizeof(U) == 4 ? '4' : '6';
			const size_t high_bit = sizeof(U) * 8 - 1;

			overflow = digits >= max_digits10 && !(digits == max_digits10 && (*start < max_lead || (*start == max_lead && result >> high_bit)));
		}

		if (negative)
		{
			// Workaround for crayc++ CC-3059: Expected no overflow in routine.
		#ifdef _CRAYC
			return (overflow || result > ~minv + 1) ? minv : ~result + 1;
		#else
			return (overflow || result > 0 - minv) ? minv : 0 - result;
		#endif
		}
		else
			return (overflow || result > maxv) ? maxv : result;
	}

	PUGI_IMPL_FN int get_value_int(const char_t* value)
	{
		return string_to_integer<unsigned int>(value, static_cast<unsigned int>(INT_MIN), INT_MAX);
	}

	PUGI_IMPL_FN unsigned int get_value_uint(const char_t* value)
	{
		return string_to_integer<unsigned int>(value, 0, UINT_MAX);
	}

	PUGI_IMPL_FN double get_value_double(const char_t* value)
	{
	#ifdef PUGIXML_WCHAR_MODE
		return wcstod(value, 0);
	#else
		return strtod(value, 0);
	#endif
	}

	PUGI_IMPL_FN float get_value_float(const char_t* value)
	{
	#ifdef PUGIXML_WCHAR_MODE
		return static_cast<float>(wcstod(value, 0));
	#else
		return static_cast<float>(strtod(value, 0));
	#endif
	}

	PUGI_IMPL_FN bool get_value_bool(const char_t* value)
	{
		// only look at first char
		char_t first = *value;

		// 1*, t* (true), T* (True), y* (yes), Y* (YES)
		return (first == '1' || first == 't' || first == 'T' || first == 'y' || first == 'Y');
	}

#ifdef PUGIXML_HAS_LONG_LONG
	PUGI_IMPL_FN long long get_value_llong(const char_t* value)
	{
		return string_to_integer<unsigned long long>(value, static_cast<unsigned long long>(LLONG_MIN), LLONG_MAX);
	}

	PUGI_IMPL_FN unsigned long long get_value_ullong(const char_t* value)
	{
		return string_to_integer<unsigned long long>(value, 0, ULLONG_MAX);
	}
#endif

	template <typename U> PUGI_IMPL_FN PUGI_IMPL_UNSIGNED_OVERFLOW char_t* integer_to_string(char_t* begin, char_t* end, U value, bool negative)
	{
		char_t* result = end - 1;
		U rest = negative ? 0 - value : value;

		do
		{
			*result-- = static_cast<char_t>('0' + (rest % 10));
			rest /= 10;
		}
		while (rest);

		assert(result >= begin);
		(void)begin;

		*result = '-';

		return result + !negative;
	}

	// set value with conversion functions
	template <typename String, typename Header>
	PUGI_IMPL_FN bool set_value_ascii(String& dest, Header& header, uintptr_t header_mask, char* buf)
	{
	#ifdef PUGIXML_WCHAR_MODE
		char_t wbuf[128];
		assert(strlen(buf) < sizeof(wbuf) / sizeof(wbuf[0]));

		size_t offset = 0;
		for (; buf[offset]; ++offset) wbuf[offset] = buf[offset];

		return strcpy_insitu(dest, header, header_mask, wbuf, offset);
	#else
		return strcpy_insitu(dest, header, header_mask, buf, strlen(buf));
	#endif
	}

	template <typename U, typename String, typename Header>
	PUGI_IMPL_FN bool set_value_integer(String& dest, Header& header, uintptr_t header_mask, U value, bool negative)
	{
		char_t buf[64];
		char_t* end = buf + sizeof(buf) / sizeof(buf[0]);
		char_t* begin = integer_to_string(buf, end, value, negative);

		return strcpy_insitu(dest, header, header_mask, begin, end - begin);
	}

	template <typename String, typename Header>
	PUGI_IMPL_FN bool set_value_convert(String& dest, Header& header, uintptr_t header_mask, float value, int precision)
	{
		char buf[128];
		PUGI_IMPL_SNPRINTF(buf, "%.*g", precision, double(value));

		return set_value_ascii(dest, header, header_mask, buf);
	}

	template <typename String, typename Header>
	PUGI_IMPL_FN bool set_value_convert(String& dest, Header& header, uintptr_t header_mask, double value, int precision)
	{
		char buf[128];
		PUGI_IMPL_SNPRINTF(buf, "%.*g", precision, value);

		return set_value_ascii(dest, header, header_mask, buf);
	}

	template <typename String, typename Header>
	PUGI_IMPL_FN bool set_value_bool(String& dest, Header& header, uintptr_t header_mask, bool value)
	{
		return strcpy_insitu(dest, header, header_mask, value ? PUGIXML_TEXT("true") : PUGIXML_TEXT("false"), value ? 4 : 5);
	}

	PUGI_IMPL_FN xml_parse_result load_buffer_impl(xml_document_struct* doc, xml_node_struct* root, void* contents, size_t size, unsigned int options, xml_encoding encoding, bool is_mutable, bool own, char_t** out_buffer)
	{
		// check input buffer
		if (!contents && size) return make_parse_result(status_io_error);

		// get actual encoding
		xml_encoding buffer_encoding = impl::get_buffer_encoding(encoding, contents, size);

		// if convert_buffer below throws bad_alloc, we still need to deallocate contents if we own it
		auto_deleter<void> contents_guard(own ? contents : 0, xml_memory::deallocate);

		// get private buffer
		char_t* buffer = 0;
		size_t length = 0;

		// coverity[var_deref_model]
		if (!impl::convert_buffer(buffer, length, buffer_encoding, contents, size, is_mutable)) return impl::make_parse_result(status_out_of_memory);

		// after this we either deallocate contents (below) or hold on to it via doc->buffer, so we don't need to guard it
		contents_guard.release();

		// delete original buffer if we performed a conversion
		if (own && buffer != contents && contents) impl::xml_memory::deallocate(contents);

		// grab onto buffer if it's our buffer, user is responsible for deallocating contents himself
		if (own || buffer != contents) *out_buffer = buffer;

		// store buffer for offset_debug
		doc->buffer = buffer;

		// parse
		xml_parse_result res = impl::xml_parser::parse(buffer, length, doc, root, options);

		// remember encoding
		res.encoding = buffer_encoding;

		return res;
	}

	// we need to get length of entire file to load it in memory; the only (relatively) sane way to do it is via seek/tell trick
	PUGI_IMPL_FN xml_parse_status get_file_size(FILE* file, size_t& out_result)
	{
	#if defined(__linux__) || defined(__APPLE__)
		// this simultaneously retrieves the file size and file mode (to guard against loading non-files)
		struct stat st;
		if (fstat(fileno(file), &st) != 0) return status_io_error;

		// anything that's not a regular file doesn't have a coherent length
		if (!S_ISREG(st.st_mode)) return status_io_error;

		typedef off_t length_type;
		length_type length = st.st_size;
	#elif defined(PUGI_IMPL_MSVC_CRT_VERSION) && PUGI_IMPL_MSVC_CRT_VERSION >= 1400
		// there are 64-bit versions of fseek/ftell, let's use them
		typedef __int64 length_type;

		_fseeki64(file, 0, SEEK_END);
		length_type length = _ftelli64(file);
		_fseeki64(file, 0, SEEK_SET);
	#elif defined(__MINGW32__) && !defined(__NO_MINGW_LFS) && (!defined(__STRICT_ANSI__) || defined(__MINGW64_VERSION_MAJOR))
		// there are 64-bit versions of fseek/ftell, let's use them
		typedef off64_t length_type;

		fseeko64(file, 0, SEEK_END);
		length_type length = ftello64(file);
		fseeko64(file, 0, SEEK_SET);
	#else
		// if this is a 32-bit OS, long is enough; if this is a unix system, long is 64-bit, which is enough; otherwise we can't do anything anyway.
		typedef long length_type;

		fseek(file, 0, SEEK_END);
		length_type length = ftell(file);
		fseek(file, 0, SEEK_SET);
	#endif

		// check for I/O errors
		if (length < 0) return status_io_error;

		// check for overflow
		size_t result = static_cast<size_t>(length);

		if (static_cast<length_type>(result) != length) return status_out_of_memory;

		// finalize
		out_result = result;

		return status_ok;
	}

	// This function assumes that buffer has extra sizeof(char_t) writable bytes after size
	PUGI_IMPL_FN size_t zero_terminate_buffer(void* buffer, size_t size, xml_encoding encoding)
	{
		// We only need to zero-terminate if encoding conversion does not do it for us
	#ifdef PUGIXML_WCHAR_MODE
		xml_encoding wchar_encoding = get_wchar_encoding();

		if (encoding == wchar_encoding || need_endian_swap_utf(encoding, wchar_encoding))
		{
			size_t length = size / sizeof(char_t);

			static_cast<char_t*>(buffer)[length] = 0;
			return (length + 1) * sizeof(char_t);
		}
	#else
		if (encoding == encoding_utf8)
		{
			static_cast<char*>(buffer)[size] = 0;
			return size + 1;
		}
	#endif

		return size;
	}

	PUGI_IMPL_FN xml_parse_result load_file_impl(xml_document_struct* doc, FILE* file, unsigned int options, xml_encoding encoding, char_t** out_buffer)
	{
		if (!file) return make_parse_result(status_file_not_found);

		// get file size (can result in I/O errors)
		size_t size = 0;
		xml_parse_status size_status = get_file_size(file, size);
		if (size_status != status_ok) return make_parse_result(size_status);

		size_t max_suffix_size = sizeof(char_t);

		// allocate buffer for the whole file
		char* contents = static_cast<char*>(xml_memory::allocate(size + max_suffix_size));
		if (!contents) return make_parse_result(status_out_of_memory);

		// read file in memory
		size_t read_size = fread(contents, 1, size, file);

		if (read_size != size)
		{
			xml_memory::deallocate(contents);
			return make_parse_result(status_io_error);
		}

		xml_encoding real_encoding = get_buffer_encoding(encoding, contents, size);

		return load_buffer_impl(doc, doc, contents, zero_terminate_buffer(contents, size, real_encoding), options, real_encoding, true, true, out_buffer);
	}

	PUGI_IMPL_FN void close_file(FILE* file)
	{
		fclose(file);
	}

#ifndef PUGIXML_NO_STL
	template <typename T> struct xml_stream_chunk
	{
		static xml_stream_chunk* create()
		{
			void* memory = xml_memory::allocate(sizeof(xml_stream_chunk));
			if (!memory) return 0;

			return new (memory) xml_stream_chunk();
		}

		static void destroy(xml_stream_chunk* chunk)
		{
			// free chunk chain
			while (chunk)
			{
				xml_stream_chunk* next_ = chunk->next;

				xml_memory::deallocate(chunk);

				chunk = next_;
			}
		}

		xml_stream_chunk(): next(0), size(0)
		{
		}

		xml_stream_chunk* next;
		size_t size;

		T data[xml_memory_page_size / sizeof(T)];
	};

	template <typename T> PUGI_IMPL_FN xml_parse_status load_stream_data_noseek(std::basic_istream<T>& stream, void** out_buffer, size_t* out_size)
	{
		auto_deleter<xml_stream_chunk<T> > chunks(0, xml_stream_chunk<T>::destroy);

		// read file to a chunk list
		size_t total = 0;
		xml_stream_chunk<T>* last = 0;

		while (!stream.eof())
		{
			// allocate new chunk
			xml_stream_chunk<T>* chunk = xml_stream_chunk<T>::create();
			if (!chunk) return status_out_of_memory;

			// append chunk to list
			if (last) last = last->next = chunk;
			else chunks.data = last = chunk;

			// read data to chunk
			stream.read(chunk->data, static_cast<std::streamsize>(sizeof(chunk->data) / sizeof(T)));
			chunk->size = static_cast<size_t>(stream.gcount()) * sizeof(T);

			// read may set failbit | eofbit in case gcount() is less than read length, so check for other I/O errors
			if (stream.bad() || (!stream.eof() && stream.fail())) return status_io_error;

			// guard against huge files (chunk size is small enough to make this overflow check work)
			if (total + chunk->size < total) return status_out_of_memory;
			total += chunk->size;
		}

		size_t max_suffix_size = sizeof(char_t);

		// copy chunk list to a contiguous buffer
		char* buffer = static_cast<char*>(xml_memory::allocate(total + max_suffix_size));
		if (!buffer) return status_out_of_memory;

		char* write = buffer;

		for (xml_stream_chunk<T>* chunk = chunks.data; chunk; chunk = chunk->next)
		{
			assert(write + chunk->size <= buffer + total);
			memcpy(write, chunk->data, chunk->size);
			write += chunk->size;
		}

		assert(write == buffer + total);

		// return buffer
		*out_buffer = buffer;
		*out_size = total;

		return status_ok;
	}

	template <typename T> PUGI_IMPL_FN xml_parse_status load_stream_data_seek(std::basic_istream<T>& stream, void** out_buffer, size_t* out_size)
	{
		// get length of remaining data in stream
		typename std::basic_istream<T>::pos_type pos = stream.tellg();
		stream.seekg(0, std::ios::end);
		std::streamoff length = stream.tellg() - pos;
		stream.seekg(pos);

		if (stream.fail() || pos < 0) return status_io_error;

		// guard against huge files
		size_t read_length = static_cast<size_t>(length);

		if (static_cast<std::streamsize>(read_length) != length || length < 0) return status_out_of_memory;

		size_t max_suffix_size = sizeof(char_t);

		// read stream data into memory (guard against stream exceptions with buffer holder)
		auto_deleter<void> buffer(xml_memory::allocate(read_length * sizeof(T) + max_suffix_size), xml_memory::deallocate);
		if (!buffer.data) return status_out_of_memory;

		stream.read(static_cast<T*>(buffer.data), static_cast<std::streamsize>(read_length));

		// read may set failbit | eofbit in case gcount() is less than read_length (i.e. line ending conversion), so check for other I/O errors
		if (stream.bad() || (!stream.eof() && stream.fail())) return status_io_error;

		// return buffer
		size_t actual_length = static_cast<size_t>(stream.gcount());
		assert(actual_length <= read_length);

		*out_buffer = buffer.release();
		*out_size = actual_length * sizeof(T);

		return status_ok;
	}

	template <typename T> PUGI_IMPL_FN xml_parse_result load_stream_impl(xml_document_struct* doc, std::basic_istream<T>& stream, unsigned int options, xml_encoding encoding, char_t** out_buffer)
	{
		void* buffer = 0;
		size_t size = 0;
		xml_parse_status status = status_ok;

		// if stream has an error bit set, bail out (otherwise tellg() can fail and we'll clear error bits)
		if (stream.fail()) return make_parse_result(status_io_error);

		// load stream to memory (using seek-based implementation if possible, since it's faster and takes less memory)
		if (stream.tellg() < 0)
		{
			stream.clear(); // clear error flags that could be set by a failing tellg
			status = load_stream_data_noseek(stream, &buffer, &size);
		}
		else
			status = load_stream_data_seek(stream, &buffer, &size);

		if (status != status_ok) return make_parse_result(status);

		xml_encoding real_encoding = get_buffer_encoding(encoding, buffer, size);

		return load_buffer_impl(doc, doc, buffer, zero_terminate_buffer(buffer, size, real_encoding), options, real_encoding, true, true, out_buffer);
	}
#endif

#if defined(PUGI_IMPL_MSVC_CRT_VERSION) || defined(__BORLANDC__) || (defined(__MINGW32__) && (!defined(__STRICT_ANSI__) || defined(__MINGW64_VERSION_MAJOR)))
	PUGI_IMPL_FN FILE* open_file_wide(const wchar_t* path, const wchar_t* mode)
	{
#if defined(PUGI_IMPL_MSVC_CRT_VERSION) && PUGI_IMPL_MSVC_CRT_VERSION >= 1400
		FILE* file = 0;
		return _wfopen_s(&file, path, mode) == 0 ? file : 0;
#else
		return _wfopen(path, mode);
#endif
	}
#else
	PUGI_IMPL_FN char* convert_path_heap(const wchar_t* str)
	{
		assert(str);

		// first pass: get length in utf8 characters
		size_t length = strlength_wide(str);
		size_t size = as_utf8_begin(str, length);

		// allocate resulting string
		char* result = static_cast<char*>(xml_memory::allocate(size + 1));
		if (!result) return 0;

		// second pass: convert to utf8
		as_utf8_end(result, size, str, length);

		// zero-terminate
		result[size] = 0;

		return result;
	}

	PUGI_IMPL_FN FILE* open_file_wide(const wchar_t* path, const wchar_t* mode)
	{
		// there is no standard function to open wide paths, so our best bet is to try utf8 path
		char* path_utf8 = convert_path_heap(path);
		if (!path_utf8) return 0;

		// convert mode to ASCII (we mirror _wfopen interface)
		char mode_ascii[4] = {0};
		for (size_t i = 0; mode[i]; ++i) mode_ascii[i] = static_cast<char>(mode[i]);

		// try to open the utf8 path
		FILE* result = fopen(path_utf8, mode_ascii);

		// free dummy buffer
		xml_memory::deallocate(path_utf8);

		return result;
	}
#endif

	PUGI_IMPL_FN FILE* open_file(const char* path, const char* mode)
	{
#if defined(PUGI_IMPL_MSVC_CRT_VERSION) && PUGI_IMPL_MSVC_CRT_VERSION >= 1400
		FILE* file = 0;
		return fopen_s(&file, path, mode) == 0 ? file : 0;
#else
		return fopen(path, mode);
#endif
	}

	PUGI_IMPL_FN bool save_file_impl(const xml_document& doc, FILE* file, const char_t* indent, unsigned int flags, xml_encoding encoding)
	{
		if (!file) return false;

		xml_writer_file writer(file);
		doc.save(writer, indent, flags, encoding);

		return fflush(file) == 0 && ferror(file) == 0;
	}

	struct name_null_sentry
	{
		xml_node_struct* node;
		char_t* name;

		name_null_sentry(xml_node_struct* node_): node(node_), name(node_->name)
		{
			node->name = 0;
		}

		~name_null_sentry()
		{
			node->name = name;
		}
	};
PUGI_IMPL_NS_END

namespace pugi
{
	PUGI_IMPL_FN xml_writer::~xml_writer()
	{
	}

	PUGI_IMPL_FN xml_writer_file::xml_writer_file(void* file_): file(file_)
	{
	}

	PUGI_IMPL_FN void xml_writer_file::write(const void* data, size_t size)
	{
		size_t result = fwrite(data, 1, size, static_cast<FILE*>(file));
		(void)!result; // unfortunately we can't do proper error handling here
	}

#ifndef PUGIXML_NO_STL
	PUGI_IMPL_FN xml_writer_stream::xml_writer_stream(std::basic_ostream<char, std::char_traits<char> >& stream): narrow_stream(&stream), wide_stream(0)
	{
	}

	PUGI_IMPL_FN xml_writer_stream::xml_writer_stream(std::basic_ostream<wchar_t, std::char_traits<wchar_t> >& stream): narrow_stream(0), wide_stream(&stream)
	{
	}

	PUGI_IMPL_FN void xml_writer_stream::write(const void* data, size_t size)
	{
		if (narrow_stream)
		{
			assert(!wide_stream);
			narrow_stream->write(reinterpret_cast<const char*>(data), static_cast<std::streamsize>(size));
		}
		else
		{
			assert(wide_stream);
			assert(size % sizeof(wchar_t) == 0);

			wide_stream->write(reinterpret_cast<const wchar_t*>(data), static_cast<std::streamsize>(size / sizeof(wchar_t)));
		}
	}
#endif

	PUGI_IMPL_FN xml_tree_walker::xml_tree_walker(): _depth(0)
	{
	}

	PUGI_IMPL_FN xml_tree_walker::~xml_tree_walker()
	{
	}

	PUGI_IMPL_FN int xml_tree_walker::depth() const
	{
		return _depth;
	}

	PUGI_IMPL_FN bool xml_tree_walker::begin(xml_node&)
	{
		return true;
	}

	PUGI_IMPL_FN bool xml_tree_walker::end(xml_node&)
	{
		return true;
	}

	PUGI_IMPL_FN xml_attribute::xml_attribute(): _attr(0)
	{
	}

	PUGI_IMPL_FN xml_attribute::xml_attribute(xml_attribute_struct* attr): _attr(attr)
	{
	}

	PUGI_IMPL_FN static void unspecified_bool_xml_attribute(xml_attribute***)
	{
	}

	PUGI_IMPL_FN xml_attribute::operator xml_attribute::unspecified_bool_type() const
	{
		return _attr ? unspecified_bool_xml_attribute : 0;
	}

	PUGI_IMPL_FN bool xml_attribute::operator!() const
	{
		return !_attr;
	}

	PUGI_IMPL_FN bool xml_attribute::operator==(const xml_attribute& r) const
	{
		return (_attr == r._attr);
	}

	PUGI_IMPL_FN bool xml_attribute::operator!=(const xml_attribute& r) const
	{
		return (_attr != r._attr);
	}

	PUGI_IMPL_FN bool xml_attribute::operator<(const xml_attribute& r) const
	{
		return (_attr < r._attr);
	}

	PUGI_IMPL_FN bool xml_attribute::operator>(const xml_attribute& r) const
	{
		return (_attr > r._attr);
	}

	PUGI_IMPL_FN bool xml_attribute::operator<=(const xml_attribute& r) const
	{
		return (_attr <= r._attr);
	}

	PUGI_IMPL_FN bool xml_attribute::operator>=(const xml_attribute& r) const
	{
		return (_attr >= r._attr);
	}

	PUGI_IMPL_FN xml_attribute xml_attribute::next_attribute() const
	{
		if (!_attr) return xml_attribute();
		return xml_attribute(_attr->next_attribute);
	}

	PUGI_IMPL_FN xml_attribute xml_attribute::previous_attribute() const
	{
		if (!_attr) return xml_attribute();
		xml_attribute_struct* prev = _attr->prev_attribute_c;
		return prev->next_attribute ? xml_attribute(prev) : xml_attribute();
	}

	PUGI_IMPL_FN const char_t* xml_attribute::as_string(const char_t* def) const
	{
		if (!_attr) return def;
		const char_t* value = _attr->value;
		return value ? value : def;
	}

	PUGI_IMPL_FN int xml_attribute::as_int(int def) const
	{
		if (!_attr) return def;
		const char_t* value = _attr->value;
		return value ? impl::get_value_int(value) : def;
	}

	PUGI_IMPL_FN unsigned int xml_attribute::as_uint(unsigned int def) const
	{
		if (!_attr) return def;
		const char_t* value = _attr->value;
		return value ? impl::get_value_uint(value) : def;
	}

	PUGI_IMPL_FN double xml_attribute::as_double(double def) const
	{
		if (!_attr) return def;
		const char_t* value = _attr->value;
		return value ? impl::get_value_double(value) : def;
	}

	PUGI_IMPL_FN float xml_attribute::as_float(float def) const
	{
		if (!_attr) return def;
		const char_t* value = _attr->value;
		return value ? impl::get_value_float(value) : def;
	}

	PUGI_IMPL_FN bool xml_attribute::as_bool(bool def) const
	{
		if (!_attr) return def;
		const char_t* value = _attr->value;
		return value ? impl::get_value_bool(value) : def;
	}

#ifdef PUGIXML_HAS_LONG_LONG
	PUGI_IMPL_FN long long xml_attribute::as_llong(long long def) const
	{
		if (!_attr) return def;
		const char_t* value = _attr->value;
		return value ? impl::get_value_llong(value) : def;
	}

	PUGI_IMPL_FN unsigned long long xml_attribute::as_ullong(unsigned long long def) const
	{
		if (!_attr) return def;
		const char_t* value = _attr->value;
		return value ? impl::get_value_ullong(value) : def;
	}
#endif

	PUGI_IMPL_FN bool xml_attribute::empty() const
	{
		return !_attr;
	}

	PUGI_IMPL_FN const char_t* xml_attribute::name() const
	{
		if (!_attr) return PUGIXML_TEXT("");
		const char_t* name = _attr->name;
		return name ? name : PUGIXML_TEXT("");
	}

	PUGI_IMPL_FN const char_t* xml_attribute::value() const
	{
		if (!_attr) return PUGIXML_TEXT("");
		const char_t* value = _attr->value;
		return value ? value : PUGIXML_TEXT("");
	}

	PUGI_IMPL_FN size_t xml_attribute::hash_value() const
	{
		return static_cast<size_t>(reinterpret_cast<uintptr_t>(_attr) / sizeof(xml_attribute_struct));
	}

	PUGI_IMPL_FN xml_attribute_struct* xml_attribute::internal_object() const
	{
		return _attr;
	}

	PUGI_IMPL_FN xml_attribute& xml_attribute::operator=(const char_t* rhs)
	{
		set_value(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_attribute& xml_attribute::operator=(int rhs)
	{
		set_value(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_attribute& xml_attribute::operator=(unsigned int rhs)
	{
		set_value(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_attribute& xml_attribute::operator=(long rhs)
	{
		set_value(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_attribute& xml_attribute::operator=(unsigned long rhs)
	{
		set_value(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_attribute& xml_attribute::operator=(double rhs)
	{
		set_value(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_attribute& xml_attribute::operator=(float rhs)
	{
		set_value(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_attribute& xml_attribute::operator=(bool rhs)
	{
		set_value(rhs);
		return *this;
	}

#ifdef PUGIXML_HAS_LONG_LONG
	PUGI_IMPL_FN xml_attribute& xml_attribute::operator=(long long rhs)
	{
		set_value(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_attribute& xml_attribute::operator=(unsigned long long rhs)
	{
		set_value(rhs);
		return *this;
	}
#endif

	PUGI_IMPL_FN bool xml_attribute::set_name(const char_t* rhs)
	{
		if (!_attr) return false;

		return impl::strcpy_insitu(_attr->name, _attr->header, impl::xml_memory_page_name_allocated_mask, rhs, impl::strlength(rhs));
	}

	PUGI_IMPL_FN bool xml_attribute::set_name(const char_t* rhs, size_t size)
	{
		if (!_attr) return false;

		return impl::strcpy_insitu(_attr->name, _attr->header, impl::xml_memory_page_name_allocated_mask, rhs, size);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(const char_t* rhs)
	{
		if (!_attr) return false;

		return impl::strcpy_insitu(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, impl::strlength(rhs));
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(const char_t* rhs, size_t size)
	{
		if (!_attr) return false;

		return impl::strcpy_insitu(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, size);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(int rhs)
	{
		if (!_attr) return false;

		return impl::set_value_integer<unsigned int>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(unsigned int rhs)
	{
		if (!_attr) return false;

		return impl::set_value_integer<unsigned int>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, false);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(long rhs)
	{
		if (!_attr) return false;

		return impl::set_value_integer<unsigned long>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(unsigned long rhs)
	{
		if (!_attr) return false;

		return impl::set_value_integer<unsigned long>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, false);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(double rhs)
	{
		if (!_attr) return false;

		return impl::set_value_convert(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, default_double_precision);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(double rhs, int precision)
	{
		if (!_attr) return false;

		return impl::set_value_convert(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, precision);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(float rhs)
	{
		if (!_attr) return false;

		return impl::set_value_convert(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, default_float_precision);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(float rhs, int precision)
	{
		if (!_attr) return false;

		return impl::set_value_convert(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, precision);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(bool rhs)
	{
		if (!_attr) return false;

		return impl::set_value_bool(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs);
	}

#ifdef PUGIXML_HAS_LONG_LONG
	PUGI_IMPL_FN bool xml_attribute::set_value(long long rhs)
	{
		if (!_attr) return false;

		return impl::set_value_integer<unsigned long long>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0);
	}

	PUGI_IMPL_FN bool xml_attribute::set_value(unsigned long long rhs)
	{
		if (!_attr) return false;

		return impl::set_value_integer<unsigned long long>(_attr->value, _attr->header, impl::xml_memory_page_value_allocated_mask, rhs, false);
	}
#endif

#ifdef __BORLANDC__
	PUGI_IMPL_FN bool operator&&(const xml_attribute& lhs, bool rhs)
	{
		return (bool)lhs && rhs;
	}

	PUGI_IMPL_FN bool operator||(const xml_attribute& lhs, bool rhs)
	{
		return (bool)lhs || rhs;
	}
#endif

	PUGI_IMPL_FN xml_node::xml_node(): _root(0)
	{
	}

	PUGI_IMPL_FN xml_node::xml_node(xml_node_struct* p): _root(p)
	{
	}

	PUGI_IMPL_FN static void unspecified_bool_xml_node(xml_node***)
	{
	}

	PUGI_IMPL_FN xml_node::operator xml_node::unspecified_bool_type() const
	{
		return _root ? unspecified_bool_xml_node : 0;
	}

	PUGI_IMPL_FN bool xml_node::operator!() const
	{
		return !_root;
	}

	PUGI_IMPL_FN xml_node::iterator xml_node::begin() const
	{
		return iterator(_root ? _root->first_child + 0 : 0, _root);
	}

	PUGI_IMPL_FN xml_node::iterator xml_node::end() const
	{
		return iterator(0, _root);
	}

	PUGI_IMPL_FN xml_node::attribute_iterator xml_node::attributes_begin() const
	{
		return attribute_iterator(_root ? _root->first_attribute + 0 : 0, _root);
	}

	PUGI_IMPL_FN xml_node::attribute_iterator xml_node::attributes_end() const
	{
		return attribute_iterator(0, _root);
	}

	PUGI_IMPL_FN xml_object_range<xml_node_iterator> xml_node::children() const
	{
		return xml_object_range<xml_node_iterator>(begin(), end());
	}

	PUGI_IMPL_FN xml_object_range<xml_named_node_iterator> xml_node::children(const char_t* name_) const
	{
		return xml_object_range<xml_named_node_iterator>(xml_named_node_iterator(child(name_)._root, _root, name_), xml_named_node_iterator(0, _root, name_));
	}

	PUGI_IMPL_FN xml_object_range<xml_attribute_iterator> xml_node::attributes() const
	{
		return xml_object_range<xml_attribute_iterator>(attributes_begin(), attributes_end());
	}

	PUGI_IMPL_FN bool xml_node::operator==(const xml_node& r) const
	{
		return (_root == r._root);
	}

	PUGI_IMPL_FN bool xml_node::operator!=(const xml_node& r) const
	{
		return (_root != r._root);
	}

	PUGI_IMPL_FN bool xml_node::operator<(const xml_node& r) const
	{
		return (_root < r._root);
	}

	PUGI_IMPL_FN bool xml_node::operator>(const xml_node& r) const
	{
		return (_root > r._root);
	}

	PUGI_IMPL_FN bool xml_node::operator<=(const xml_node& r) const
	{
		return (_root <= r._root);
	}

	PUGI_IMPL_FN bool xml_node::operator>=(const xml_node& r) const
	{
		return (_root >= r._root);
	}

	PUGI_IMPL_FN bool xml_node::empty() const
	{
		return !_root;
	}

	PUGI_IMPL_FN const char_t* xml_node::name() const
	{
		if (!_root) return PUGIXML_TEXT("");
		const char_t* name = _root->name;
		return name ? name : PUGIXML_TEXT("");
	}

	PUGI_IMPL_FN xml_node_type xml_node::type() const
	{
		return _root ? PUGI_IMPL_NODETYPE(_root) : node_null;
	}

	PUGI_IMPL_FN const char_t* xml_node::value() const
	{
		if (!_root) return PUGIXML_TEXT("");
		const char_t* value = _root->value;
		return value ? value : PUGIXML_TEXT("");
	}

	PUGI_IMPL_FN xml_node xml_node::child(const char_t* name_) const
	{
		if (!_root) return xml_node();

		for (xml_node_struct* i = _root->first_child; i; i = i->next_sibling)
		{
			const char_t* iname = i->name;
			if (iname && impl::strequal(name_, iname))
				return xml_node(i);
		}

		return xml_node();
	}

	PUGI_IMPL_FN xml_attribute xml_node::attribute(const char_t* name_) const
	{
		if (!_root) return xml_attribute();

		for (xml_attribute_struct* i = _root->first_attribute; i; i = i->next_attribute)
		{
			const char_t* iname = i->name;
			if (iname && impl::strequal(name_, iname))
				return xml_attribute(i);
		}

		return xml_attribute();
	}

	PUGI_IMPL_FN xml_node xml_node::next_sibling(const char_t* name_) const
	{
		if (!_root) return xml_node();

		for (xml_node_struct* i = _root->next_sibling; i; i = i->next_sibling)
		{
			const char_t* iname = i->name;
			if (iname && impl::strequal(name_, iname))
				return xml_node(i);
		}

		return xml_node();
	}

	PUGI_IMPL_FN xml_node xml_node::next_sibling() const
	{
		return _root ? xml_node(_root->next_sibling) : xml_node();
	}

	PUGI_IMPL_FN xml_node xml_node::previous_sibling(const char_t* name_) const
	{
		if (!_root) return xml_node();

		for (xml_node_struct* i = _root->prev_sibling_c; i->next_sibling; i = i->prev_sibling_c)
		{
			const char_t* iname = i->name;
			if (iname && impl::strequal(name_, iname))
				return xml_node(i);
		}

		return xml_node();
	}

	PUGI_IMPL_FN xml_attribute xml_node::attribute(const char_t* name_, xml_attribute& hint_) const
	{
		xml_attribute_struct* hint = hint_._attr;

		// if hint is not an attribute of node, behavior is not defined
		assert(!hint || (_root && impl::is_attribute_of(hint, _root)));

		if (!_root) return xml_attribute();

		// optimistically search from hint up until the end
		for (xml_attribute_struct* i = hint; i; i = i->next_attribute)
		{
			const char_t* iname = i->name;
			if (iname && impl::strequal(name_, iname))
			{
				// update hint to maximize efficiency of searching for consecutive attributes
				hint_._attr = i->next_attribute;

				return xml_attribute(i);
			}
		}

		// wrap around and search from the first attribute until the hint
		// 'j' null pointer check is technically redundant, but it prevents a crash in case the assertion above fails
		for (xml_attribute_struct* j = _root->first_attribute; j && j != hint; j = j->next_attribute)
		{
			const char_t* jname = j->name;
			if (jname && impl::strequal(name_, jname))
			{
				// update hint to maximize efficiency of searching for consecutive attributes
				hint_._attr = j->next_attribute;

				return xml_attribute(j);
			}
		}

		return xml_attribute();
	}

	PUGI_IMPL_FN xml_node xml_node::previous_sibling() const
	{
		if (!_root) return xml_node();
		xml_node_struct* prev = _root->prev_sibling_c;
		return prev->next_sibling ? xml_node(prev) : xml_node();
	}

	PUGI_IMPL_FN xml_node xml_node::parent() const
	{
		return _root ? xml_node(_root->parent) : xml_node();
	}

	PUGI_IMPL_FN xml_node xml_node::root() const
	{
		return _root ? xml_node(&impl::get_document(_root)) : xml_node();
	}

	PUGI_IMPL_FN xml_text xml_node::text() const
	{
		return xml_text(_root);
	}

	PUGI_IMPL_FN const char_t* xml_node::child_value() const
	{
		if (!_root) return PUGIXML_TEXT("");

		// element nodes can have value if parse_embed_pcdata was used
		if (PUGI_IMPL_NODETYPE(_root) == node_element && _root->value)
			return _root->value;

		for (xml_node_struct* i = _root->first_child; i; i = i->next_sibling)
		{
			const char_t* ivalue = i->value;
			if (impl::is_text_node(i) && ivalue)
				return ivalue;
		}

		return PUGIXML_TEXT("");
	}

	PUGI_IMPL_FN const char_t* xml_node::child_value(const char_t* name_) const
	{
		return child(name_).child_value();
	}

	PUGI_IMPL_FN xml_attribute xml_node::first_attribute() const
	{
		if (!_root) return xml_attribute();
		return xml_attribute(_root->first_attribute);
	}

	PUGI_IMPL_FN xml_attribute xml_node::last_attribute() const
	{
		if (!_root) return xml_attribute();
		xml_attribute_struct* first = _root->first_attribute;
		return first ? xml_attribute(first->prev_attribute_c) : xml_attribute();
	}

	PUGI_IMPL_FN xml_node xml_node::first_child() const
	{
		if (!_root) return xml_node();
		return xml_node(_root->first_child);
	}

	PUGI_IMPL_FN xml_node xml_node::last_child() const
	{
		if (!_root) return xml_node();
		xml_node_struct* first = _root->first_child;
		return first ? xml_node(first->prev_sibling_c) : xml_node();
	}

	PUGI_IMPL_FN bool xml_node::set_name(const char_t* rhs)
	{
		xml_node_type type_ = _root ? PUGI_IMPL_NODETYPE(_root) : node_null;

		if (type_ != node_element && type_ != node_pi && type_ != node_declaration)
			return false;

		return impl::strcpy_insitu(_root->name, _root->header, impl::xml_memory_page_name_allocated_mask, rhs, impl::strlength(rhs));
	}

	PUGI_IMPL_FN bool xml_node::set_name(const char_t* rhs, size_t size)
	{
		xml_node_type type_ = _root ? PUGI_IMPL_NODETYPE(_root) : node_null;

		if (type_ != node_element && type_ != node_pi && type_ != node_declaration)
			return false;

		return impl::strcpy_insitu(_root->name, _root->header, impl::xml_memory_page_name_allocated_mask, rhs, size);
	}

	PUGI_IMPL_FN bool xml_node::set_value(const char_t* rhs)
	{
		xml_node_type type_ = _root ? PUGI_IMPL_NODETYPE(_root) : node_null;

		if (type_ != node_pcdata && type_ != node_cdata && type_ != node_comment && type_ != node_pi && type_ != node_doctype)
			return false;

		return impl::strcpy_insitu(_root->value, _root->header, impl::xml_memory_page_value_allocated_mask, rhs, impl::strlength(rhs));
	}

	PUGI_IMPL_FN bool xml_node::set_value(const char_t* rhs, size_t size)
	{
		xml_node_type type_ = _root ? PUGI_IMPL_NODETYPE(_root) : node_null;

		if (type_ != node_pcdata && type_ != node_cdata && type_ != node_comment && type_ != node_pi && type_ != node_doctype)
			return false;

		return impl::strcpy_insitu(_root->value, _root->header, impl::xml_memory_page_value_allocated_mask, rhs, size);
	}

	PUGI_IMPL_FN xml_attribute xml_node::append_attribute(const char_t* name_)
	{
		if (!impl::allow_insert_attribute(type())) return xml_attribute();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_attribute();

		xml_attribute a(impl::allocate_attribute(alloc));
		if (!a) return xml_attribute();

		impl::append_attribute(a._attr, _root);

		a.set_name(name_);

		return a;
	}

	PUGI_IMPL_FN xml_attribute xml_node::prepend_attribute(const char_t* name_)
	{
		if (!impl::allow_insert_attribute(type())) return xml_attribute();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_attribute();

		xml_attribute a(impl::allocate_attribute(alloc));
		if (!a) return xml_attribute();

		impl::prepend_attribute(a._attr, _root);

		a.set_name(name_);

		return a;
	}

	PUGI_IMPL_FN xml_attribute xml_node::insert_attribute_after(const char_t* name_, const xml_attribute& attr)
	{
		if (!impl::allow_insert_attribute(type())) return xml_attribute();
		if (!attr || !impl::is_attribute_of(attr._attr, _root)) return xml_attribute();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_attribute();

		xml_attribute a(impl::allocate_attribute(alloc));
		if (!a) return xml_attribute();

		impl::insert_attribute_after(a._attr, attr._attr, _root);

		a.set_name(name_);

		return a;
	}

	PUGI_IMPL_FN xml_attribute xml_node::insert_attribute_before(const char_t* name_, const xml_attribute& attr)
	{
		if (!impl::allow_insert_attribute(type())) return xml_attribute();
		if (!attr || !impl::is_attribute_of(attr._attr, _root)) return xml_attribute();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_attribute();

		xml_attribute a(impl::allocate_attribute(alloc));
		if (!a) return xml_attribute();

		impl::insert_attribute_before(a._attr, attr._attr, _root);

		a.set_name(name_);

		return a;
	}

	PUGI_IMPL_FN xml_attribute xml_node::append_copy(const xml_attribute& proto)
	{
		if (!proto) return xml_attribute();
		if (!impl::allow_insert_attribute(type())) return xml_attribute();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_attribute();

		xml_attribute a(impl::allocate_attribute(alloc));
		if (!a) return xml_attribute();

		impl::append_attribute(a._attr, _root);
		impl::node_copy_attribute(a._attr, proto._attr);

		return a;
	}

	PUGI_IMPL_FN xml_attribute xml_node::prepend_copy(const xml_attribute& proto)
	{
		if (!proto) return xml_attribute();
		if (!impl::allow_insert_attribute(type())) return xml_attribute();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_attribute();

		xml_attribute a(impl::allocate_attribute(alloc));
		if (!a) return xml_attribute();

		impl::prepend_attribute(a._attr, _root);
		impl::node_copy_attribute(a._attr, proto._attr);

		return a;
	}

	PUGI_IMPL_FN xml_attribute xml_node::insert_copy_after(const xml_attribute& proto, const xml_attribute& attr)
	{
		if (!proto) return xml_attribute();
		if (!impl::allow_insert_attribute(type())) return xml_attribute();
		if (!attr || !impl::is_attribute_of(attr._attr, _root)) return xml_attribute();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_attribute();

		xml_attribute a(impl::allocate_attribute(alloc));
		if (!a) return xml_attribute();

		impl::insert_attribute_after(a._attr, attr._attr, _root);
		impl::node_copy_attribute(a._attr, proto._attr);

		return a;
	}

	PUGI_IMPL_FN xml_attribute xml_node::insert_copy_before(const xml_attribute& proto, const xml_attribute& attr)
	{
		if (!proto) return xml_attribute();
		if (!impl::allow_insert_attribute(type())) return xml_attribute();
		if (!attr || !impl::is_attribute_of(attr._attr, _root)) return xml_attribute();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_attribute();

		xml_attribute a(impl::allocate_attribute(alloc));
		if (!a) return xml_attribute();

		impl::insert_attribute_before(a._attr, attr._attr, _root);
		impl::node_copy_attribute(a._attr, proto._attr);

		return a;
	}

	PUGI_IMPL_FN xml_node xml_node::append_child(xml_node_type type_)
	{
		if (!impl::allow_insert_child(type(), type_)) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		xml_node n(impl::allocate_node(alloc, type_));
		if (!n) return xml_node();

		impl::append_node(n._root, _root);

		if (type_ == node_declaration) n.set_name(PUGIXML_TEXT("xml"));

		return n;
	}

	PUGI_IMPL_FN xml_node xml_node::prepend_child(xml_node_type type_)
	{
		if (!impl::allow_insert_child(type(), type_)) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		xml_node n(impl::allocate_node(alloc, type_));
		if (!n) return xml_node();

		impl::prepend_node(n._root, _root);

		if (type_ == node_declaration) n.set_name(PUGIXML_TEXT("xml"));

		return n;
	}

	PUGI_IMPL_FN xml_node xml_node::insert_child_before(xml_node_type type_, const xml_node& node)
	{
		if (!impl::allow_insert_child(type(), type_)) return xml_node();
		if (!node._root || node._root->parent != _root) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		xml_node n(impl::allocate_node(alloc, type_));
		if (!n) return xml_node();

		impl::insert_node_before(n._root, node._root);

		if (type_ == node_declaration) n.set_name(PUGIXML_TEXT("xml"));

		return n;
	}

	PUGI_IMPL_FN xml_node xml_node::insert_child_after(xml_node_type type_, const xml_node& node)
	{
		if (!impl::allow_insert_child(type(), type_)) return xml_node();
		if (!node._root || node._root->parent != _root) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		xml_node n(impl::allocate_node(alloc, type_));
		if (!n) return xml_node();

		impl::insert_node_after(n._root, node._root);

		if (type_ == node_declaration) n.set_name(PUGIXML_TEXT("xml"));

		return n;
	}

	PUGI_IMPL_FN xml_node xml_node::append_child(const char_t* name_)
	{
		xml_node result = append_child(node_element);

		result.set_name(name_);

		return result;
	}

	PUGI_IMPL_FN xml_node xml_node::prepend_child(const char_t* name_)
	{
		xml_node result = prepend_child(node_element);

		result.set_name(name_);

		return result;
	}

	PUGI_IMPL_FN xml_node xml_node::insert_child_after(const char_t* name_, const xml_node& node)
	{
		xml_node result = insert_child_after(node_element, node);

		result.set_name(name_);

		return result;
	}

	PUGI_IMPL_FN xml_node xml_node::insert_child_before(const char_t* name_, const xml_node& node)
	{
		xml_node result = insert_child_before(node_element, node);

		result.set_name(name_);

		return result;
	}

	PUGI_IMPL_FN xml_node xml_node::append_copy(const xml_node& proto)
	{
		xml_node_type type_ = proto.type();
		if (!impl::allow_insert_child(type(), type_)) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		xml_node n(impl::allocate_node(alloc, type_));
		if (!n) return xml_node();

		impl::append_node(n._root, _root);
		impl::node_copy_tree(n._root, proto._root);

		return n;
	}

	PUGI_IMPL_FN xml_node xml_node::prepend_copy(const xml_node& proto)
	{
		xml_node_type type_ = proto.type();
		if (!impl::allow_insert_child(type(), type_)) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		xml_node n(impl::allocate_node(alloc, type_));
		if (!n) return xml_node();

		impl::prepend_node(n._root, _root);
		impl::node_copy_tree(n._root, proto._root);

		return n;
	}

	PUGI_IMPL_FN xml_node xml_node::insert_copy_after(const xml_node& proto, const xml_node& node)
	{
		xml_node_type type_ = proto.type();
		if (!impl::allow_insert_child(type(), type_)) return xml_node();
		if (!node._root || node._root->parent != _root) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		xml_node n(impl::allocate_node(alloc, type_));
		if (!n) return xml_node();

		impl::insert_node_after(n._root, node._root);
		impl::node_copy_tree(n._root, proto._root);

		return n;
	}

	PUGI_IMPL_FN xml_node xml_node::insert_copy_before(const xml_node& proto, const xml_node& node)
	{
		xml_node_type type_ = proto.type();
		if (!impl::allow_insert_child(type(), type_)) return xml_node();
		if (!node._root || node._root->parent != _root) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		xml_node n(impl::allocate_node(alloc, type_));
		if (!n) return xml_node();

		impl::insert_node_before(n._root, node._root);
		impl::node_copy_tree(n._root, proto._root);

		return n;
	}

	PUGI_IMPL_FN xml_node xml_node::append_move(const xml_node& moved)
	{
		if (!impl::allow_move(*this, moved)) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		// disable document_buffer_order optimization since moving nodes around changes document order without changing buffer pointers
		impl::get_document(_root).header |= impl::xml_memory_page_contents_shared_mask;

		impl::remove_node(moved._root);
		impl::append_node(moved._root, _root);

		return moved;
	}

	PUGI_IMPL_FN xml_node xml_node::prepend_move(const xml_node& moved)
	{
		if (!impl::allow_move(*this, moved)) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		// disable document_buffer_order optimization since moving nodes around changes document order without changing buffer pointers
		impl::get_document(_root).header |= impl::xml_memory_page_contents_shared_mask;

		impl::remove_node(moved._root);
		impl::prepend_node(moved._root, _root);

		return moved;
	}

	PUGI_IMPL_FN xml_node xml_node::insert_move_after(const xml_node& moved, const xml_node& node)
	{
		if (!impl::allow_move(*this, moved)) return xml_node();
		if (!node._root || node._root->parent != _root) return xml_node();
		if (moved._root == node._root) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		// disable document_buffer_order optimization since moving nodes around changes document order without changing buffer pointers
		impl::get_document(_root).header |= impl::xml_memory_page_contents_shared_mask;

		impl::remove_node(moved._root);
		impl::insert_node_after(moved._root, node._root);

		return moved;
	}

	PUGI_IMPL_FN xml_node xml_node::insert_move_before(const xml_node& moved, const xml_node& node)
	{
		if (!impl::allow_move(*this, moved)) return xml_node();
		if (!node._root || node._root->parent != _root) return xml_node();
		if (moved._root == node._root) return xml_node();

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return xml_node();

		// disable document_buffer_order optimization since moving nodes around changes document order without changing buffer pointers
		impl::get_document(_root).header |= impl::xml_memory_page_contents_shared_mask;

		impl::remove_node(moved._root);
		impl::insert_node_before(moved._root, node._root);

		return moved;
	}

	PUGI_IMPL_FN bool xml_node::remove_attribute(const char_t* name_)
	{
		return remove_attribute(attribute(name_));
	}

	PUGI_IMPL_FN bool xml_node::remove_attribute(const xml_attribute& a)
	{
		if (!_root || !a._attr) return false;
		if (!impl::is_attribute_of(a._attr, _root)) return false;

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return false;

		impl::remove_attribute(a._attr, _root);
		impl::destroy_attribute(a._attr, alloc);

		return true;
	}

	PUGI_IMPL_FN bool xml_node::remove_attributes()
	{
		if (!_root) return false;

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return false;

		for (xml_attribute_struct* attr = _root->first_attribute; attr; )
		{
			xml_attribute_struct* next = attr->next_attribute;

			impl::destroy_attribute(attr, alloc);

			attr = next;
		}

		_root->first_attribute = 0;

		return true;
	}

	PUGI_IMPL_FN bool xml_node::remove_child(const char_t* name_)
	{
		return remove_child(child(name_));
	}

	PUGI_IMPL_FN bool xml_node::remove_child(const xml_node& n)
	{
		if (!_root || !n._root || n._root->parent != _root) return false;

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return false;

		impl::remove_node(n._root);
		impl::destroy_node(n._root, alloc);

		return true;
	}

	PUGI_IMPL_FN bool xml_node::remove_children()
	{
		if (!_root) return false;

		impl::xml_allocator& alloc = impl::get_allocator(_root);
		if (!alloc.reserve()) return false;

		for (xml_node_struct* cur = _root->first_child; cur; )
		{
			xml_node_struct* next = cur->next_sibling;

			impl::destroy_node(cur, alloc);

			cur = next;
		}

		_root->first_child = 0;

		return true;
	}

	PUGI_IMPL_FN xml_parse_result xml_node::append_buffer(const void* contents, size_t size, unsigned int options, xml_encoding encoding)
	{
		// append_buffer is only valid for elements/documents
		if (!impl::allow_insert_child(type(), node_element)) return impl::make_parse_result(status_append_invalid_root);

		// append buffer can not merge PCDATA into existing PCDATA nodes
		if ((options & parse_merge_pcdata) != 0 && last_child().type() == node_pcdata) return impl::make_parse_result(status_append_invalid_root);

		// get document node
		impl::xml_document_struct* doc = &impl::get_document(_root);

		// disable document_buffer_order optimization since in a document with multiple buffers comparing buffer pointers does not make sense
		doc->header |= impl::xml_memory_page_contents_shared_mask;

		// get extra buffer element (we'll store the document fragment buffer there so that we can deallocate it later)
		impl::xml_memory_page* page = 0;
		impl::xml_extra_buffer* extra = static_cast<impl::xml_extra_buffer*>(doc->allocate_memory(sizeof(impl::xml_extra_buffer) + sizeof(void*), page));
		(void)page;

		if (!extra) return impl::make_parse_result(status_out_of_memory);

	#ifdef PUGIXML_COMPACT
		// align the memory block to a pointer boundary; this is required for compact mode where memory allocations are only 4b aligned
		// note that this requires up to sizeof(void*)-1 additional memory, which the allocation above takes into account
		extra = reinterpret_cast<impl::xml_extra_buffer*>((reinterpret_cast<uintptr_t>(extra) + (sizeof(void*) - 1)) & ~(sizeof(void*) - 1));
	#endif

		// add extra buffer to the list
		extra->buffer = 0;
		extra->next = doc->extra_buffers;
		doc->extra_buffers = extra;

		// name of the root has to be NULL before parsing - otherwise closing node mismatches will not be detected at the top level
		impl::name_null_sentry sentry(_root);

		return impl::load_buffer_impl(doc, _root, const_cast<void*>(contents), size, options, encoding, false, false, &extra->buffer);
	}

	PUGI_IMPL_FN xml_node xml_node::find_child_by_attribute(const char_t* name_, const char_t* attr_name, const char_t* attr_value) const
	{
		if (!_root) return xml_node();

		for (xml_node_struct* i = _root->first_child; i; i = i->next_sibling)
		{
			const char_t* iname = i->name;
			if (iname && impl::strequal(name_, iname))
			{
				for (xml_attribute_struct* a = i->first_attribute; a; a = a->next_attribute)
				{
					const char_t* aname = a->name;
					if (aname && impl::strequal(attr_name, aname))
					{
						const char_t* avalue = a->value;
						if (impl::strequal(attr_value, avalue ? avalue : PUGIXML_TEXT("")))
							return xml_node(i);
					}
				}
			}
		}

		return xml_node();
	}

	PUGI_IMPL_FN xml_node xml_node::find_child_by_attribute(const char_t* attr_name, const char_t* attr_value) const
	{
		if (!_root) return xml_node();

		for (xml_node_struct* i = _root->first_child; i; i = i->next_sibling)
			for (xml_attribute_struct* a = i->first_attribute; a; a = a->next_attribute)
			{
				const char_t* aname = a->name;
				if (aname && impl::strequal(attr_name, aname))
				{
					const char_t* avalue = a->value;
					if (impl::strequal(attr_value, avalue ? avalue : PUGIXML_TEXT("")))
						return xml_node(i);
				}
			}

		return xml_node();
	}

#ifndef PUGIXML_NO_STL
	PUGI_IMPL_FN string_t xml_node::path(char_t delimiter) const
	{
		if (!_root) return string_t();

		size_t offset = 0;

		for (xml_node_struct* i = _root; i; i = i->parent)
		{
			const char_t* iname = i->name;
			offset += (i != _root);
			offset += iname ? impl::strlength(iname) : 0;
		}

		string_t result;
		result.resize(offset);

		for (xml_node_struct* j = _root; j; j = j->parent)
		{
			if (j != _root)
				result[--offset] = delimiter;

			const char_t* jname = j->name;
			if (jname)
			{
				size_t length = impl::strlength(jname);

				offset -= length;
				memcpy(&result[offset], jname, length * sizeof(char_t));
			}
		}

		assert(offset == 0);

		return result;
	}
#endif

	PUGI_IMPL_FN xml_node xml_node::first_element_by_path(const char_t* path_, char_t delimiter) const
	{
		xml_node context = path_[0] == delimiter ? root() : *this;

		if (!context._root) return xml_node();

		const char_t* path_segment = path_;

		while (*path_segment == delimiter) ++path_segment;

		const char_t* path_segment_end = path_segment;

		while (*path_segment_end && *path_segment_end != delimiter) ++path_segment_end;

		if (path_segment == path_segment_end) return context;

		const char_t* next_segment = path_segment_end;

		while (*next_segment == delimiter) ++next_segment;

		if (*path_segment == '.' && path_segment + 1 == path_segment_end)
			return context.first_element_by_path(next_segment, delimiter);
		else if (*path_segment == '.' && *(path_segment+1) == '.' && path_segment + 2 == path_segment_end)
			return context.parent().first_element_by_path(next_segment, delimiter);
		else
		{
			for (xml_node_struct* j = context._root->first_child; j; j = j->next_sibling)
			{
				const char_t* jname = j->name;
				if (jname && impl::strequalrange(jname, path_segment, static_cast<size_t>(path_segment_end - path_segment)))
				{
					xml_node subsearch = xml_node(j).first_element_by_path(next_segment, delimiter);

					if (subsearch) return subsearch;
				}
			}

			return xml_node();
		}
	}

	PUGI_IMPL_FN bool xml_node::traverse(xml_tree_walker& walker)
	{
		walker._depth = -1;

		xml_node arg_begin(_root);
		if (!walker.begin(arg_begin)) return false;

		xml_node_struct* cur = _root ? _root->first_child + 0 : 0;

		if (cur)
		{
			++walker._depth;

			do
			{
				xml_node arg_for_each(cur);
				if (!walker.for_each(arg_for_each))
					return false;

				if (cur->first_child)
				{
					++walker._depth;
					cur = cur->first_child;
				}
				else if (cur->next_sibling)
					cur = cur->next_sibling;
				else
				{
					while (!cur->next_sibling && cur != _root && cur->parent)
					{
						--walker._depth;
						cur = cur->parent;
					}

					if (cur != _root)
						cur = cur->next_sibling;
				}
			}
			while (cur && cur != _root);
		}

		assert(walker._depth == -1);

		xml_node arg_end(_root);
		return walker.end(arg_end);
	}

	PUGI_IMPL_FN size_t xml_node::hash_value() const
	{
		return static_cast<size_t>(reinterpret_cast<uintptr_t>(_root) / sizeof(xml_node_struct));
	}

	PUGI_IMPL_FN xml_node_struct* xml_node::internal_object() const
	{
		return _root;
	}

	PUGI_IMPL_FN void xml_node::print(xml_writer& writer, const char_t* indent, unsigned int flags, xml_encoding encoding, unsigned int depth) const
	{
		if (!_root) return;

		impl::xml_buffered_writer buffered_writer(writer, encoding);

		impl::node_output(buffered_writer, _root, indent, flags, depth);

		buffered_writer.flush();
	}

#ifndef PUGIXML_NO_STL
	PUGI_IMPL_FN void xml_node::print(std::basic_ostream<char, std::char_traits<char> >& stream, const char_t* indent, unsigned int flags, xml_encoding encoding, unsigned int depth) const
	{
		xml_writer_stream writer(stream);

		print(writer, indent, flags, encoding, depth);
	}

	PUGI_IMPL_FN void xml_node::print(std::basic_ostream<wchar_t, std::char_traits<wchar_t> >& stream, const char_t* indent, unsigned int flags, unsigned int depth) const
	{
		xml_writer_stream writer(stream);

		print(writer, indent, flags, encoding_wchar, depth);
	}
#endif

	PUGI_IMPL_FN ptrdiff_t xml_node::offset_debug() const
	{
		if (!_root) return -1;

		impl::xml_document_struct& doc = impl::get_document(_root);

		// we can determine the offset reliably only if there is exactly once parse buffer
		if (!doc.buffer || doc.extra_buffers) return -1;

		switch (type())
		{
		case node_document:
			return 0;

		case node_element:
		case node_declaration:
		case node_pi:
			return _root->name && (_root->header & impl::xml_memory_page_name_allocated_or_shared_mask) == 0 ? _root->name - doc.buffer : -1;

		case node_pcdata:
		case node_cdata:
		case node_comment:
		case node_doctype:
			return _root->value && (_root->header & impl::xml_memory_page_value_allocated_or_shared_mask) == 0 ? _root->value - doc.buffer : -1;

		default:
			assert(false && "Invalid node type"); // unreachable
			return -1;
		}
	}

#ifdef __BORLANDC__
	PUGI_IMPL_FN bool operator&&(const xml_node& lhs, bool rhs)
	{
		return (bool)lhs && rhs;
	}

	PUGI_IMPL_FN bool operator||(const xml_node& lhs, bool rhs)
	{
		return (bool)lhs || rhs;
	}
#endif

	PUGI_IMPL_FN xml_text::xml_text(xml_node_struct* root): _root(root)
	{
	}

	PUGI_IMPL_FN xml_node_struct* xml_text::_data() const
	{
		if (!_root || impl::is_text_node(_root)) return _root;

		// element nodes can have value if parse_embed_pcdata was used
		if (PUGI_IMPL_NODETYPE(_root) == node_element && _root->value)
			return _root;

		for (xml_node_struct* node = _root->first_child; node; node = node->next_sibling)
			if (impl::is_text_node(node))
				return node;

		return 0;
	}

	PUGI_IMPL_FN xml_node_struct* xml_text::_data_new()
	{
		xml_node_struct* d = _data();
		if (d) return d;

		return xml_node(_root).append_child(node_pcdata).internal_object();
	}

	PUGI_IMPL_FN xml_text::xml_text(): _root(0)
	{
	}

	PUGI_IMPL_FN static void unspecified_bool_xml_text(xml_text***)
	{
	}

	PUGI_IMPL_FN xml_text::operator xml_text::unspecified_bool_type() const
	{
		return _data() ? unspecified_bool_xml_text : 0;
	}

	PUGI_IMPL_FN bool xml_text::operator!() const
	{
		return !_data();
	}

	PUGI_IMPL_FN bool xml_text::empty() const
	{
		return _data() == 0;
	}

	PUGI_IMPL_FN const char_t* xml_text::get() const
	{
		xml_node_struct* d = _data();
		if (!d) return PUGIXML_TEXT("");
		const char_t* value = d->value;
		return value ? value : PUGIXML_TEXT("");
	}

	PUGI_IMPL_FN const char_t* xml_text::as_string(const char_t* def) const
	{
		xml_node_struct* d = _data();
		if (!d) return def;
		const char_t* value = d->value;
		return value ? value : def;
	}

	PUGI_IMPL_FN int xml_text::as_int(int def) const
	{
		xml_node_struct* d = _data();
		if (!d) return def;
		const char_t* value = d->value;
		return value ? impl::get_value_int(value) : def;
	}

	PUGI_IMPL_FN unsigned int xml_text::as_uint(unsigned int def) const
	{
		xml_node_struct* d = _data();
		if (!d) return def;
		const char_t* value = d->value;
		return value ? impl::get_value_uint(value) : def;
	}

	PUGI_IMPL_FN double xml_text::as_double(double def) const
	{
		xml_node_struct* d = _data();
		if (!d) return def;
		const char_t* value = d->value;
		return value ? impl::get_value_double(value) : def;
	}

	PUGI_IMPL_FN float xml_text::as_float(float def) const
	{
		xml_node_struct* d = _data();
		if (!d) return def;
		const char_t* value = d->value;
		return value ? impl::get_value_float(value) : def;
	}

	PUGI_IMPL_FN bool xml_text::as_bool(bool def) const
	{
		xml_node_struct* d = _data();
		if (!d) return def;
		const char_t* value = d->value;
		return value ? impl::get_value_bool(value) : def;
	}

#ifdef PUGIXML_HAS_LONG_LONG
	PUGI_IMPL_FN long long xml_text::as_llong(long long def) const
	{
		xml_node_struct* d = _data();
		if (!d) return def;
		const char_t* value = d->value;
		return value ? impl::get_value_llong(value) : def;
	}

	PUGI_IMPL_FN unsigned long long xml_text::as_ullong(unsigned long long def) const
	{
		xml_node_struct* d = _data();
		if (!d) return def;
		const char_t* value = d->value;
		return value ? impl::get_value_ullong(value) : def;
	}
#endif

	PUGI_IMPL_FN bool xml_text::set(const char_t* rhs)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::strcpy_insitu(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, impl::strlength(rhs)) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(const char_t* rhs, size_t size)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::strcpy_insitu(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, size) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(int rhs)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_integer<unsigned int>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(unsigned int rhs)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_integer<unsigned int>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, false) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(long rhs)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_integer<unsigned long>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(unsigned long rhs)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_integer<unsigned long>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, false) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(float rhs)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_convert(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, default_float_precision) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(float rhs, int precision)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_convert(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, precision) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(double rhs)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_convert(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, default_double_precision) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(double rhs, int precision)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_convert(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, precision) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(bool rhs)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_bool(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs) : false;
	}

#ifdef PUGIXML_HAS_LONG_LONG
	PUGI_IMPL_FN bool xml_text::set(long long rhs)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_integer<unsigned long long>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, rhs < 0) : false;
	}

	PUGI_IMPL_FN bool xml_text::set(unsigned long long rhs)
	{
		xml_node_struct* dn = _data_new();

		return dn ? impl::set_value_integer<unsigned long long>(dn->value, dn->header, impl::xml_memory_page_value_allocated_mask, rhs, false) : false;
	}
#endif

	PUGI_IMPL_FN xml_text& xml_text::operator=(const char_t* rhs)
	{
		set(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_text& xml_text::operator=(int rhs)
	{
		set(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_text& xml_text::operator=(unsigned int rhs)
	{
		set(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_text& xml_text::operator=(long rhs)
	{
		set(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_text& xml_text::operator=(unsigned long rhs)
	{
		set(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_text& xml_text::operator=(double rhs)
	{
		set(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_text& xml_text::operator=(float rhs)
	{
		set(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_text& xml_text::operator=(bool rhs)
	{
		set(rhs);
		return *this;
	}

#ifdef PUGIXML_HAS_LONG_LONG
	PUGI_IMPL_FN xml_text& xml_text::operator=(long long rhs)
	{
		set(rhs);
		return *this;
	}

	PUGI_IMPL_FN xml_text& xml_text::operator=(unsigned long long rhs)
	{
		set(rhs);
		return *this;
	}
#endif

	PUGI_IMPL_FN xml_node xml_text::data() const
	{
		return xml_node(_data());
	}

#ifdef __BORLANDC__
	PUGI_IMPL_FN bool operator&&(const xml_text& lhs, bool rhs)
	{
		return (bool)lhs && rhs;
	}

	PUGI_IMPL_FN bool operator||(const xml_text& lhs, bool rhs)
	{
		return (bool)lhs || rhs;
	}
#endif

	PUGI_IMPL_FN xml_node_iterator::xml_node_iterator()
	{
	}

	PUGI_IMPL_FN xml_node_iterator::xml_node_iterator(const xml_node& node): _wrap(node), _parent(node.parent())
	{
	}

	PUGI_IMPL_FN xml_node_iterator::xml_node_iterator(xml_node_struct* ref, xml_node_struct* parent): _wrap(ref), _parent(parent)
	{
	}

	PUGI_IMPL_FN bool xml_node_iterator::operator==(const xml_node_iterator& rhs) const
	{
		return _wrap._root == rhs._wrap._root && _parent._root == rhs._parent._root;
	}

	PUGI_IMPL_FN bool xml_node_iterator::operator!=(const xml_node_iterator& rhs) const
	{
		return _wrap._root != rhs._wrap._root || _parent._root != rhs._parent._root;
	}

	PUGI_IMPL_FN xml_node& xml_node_iterator::operator*() const
	{
		assert(_wrap._root);
		return _wrap;
	}

	PUGI_IMPL_FN xml_node* xml_node_iterator::operator->() const
	{
		assert(_wrap._root);
		return const_cast<xml_node*>(&_wrap); // BCC5 workaround
	}

	PUGI_IMPL_FN xml_node_iterator& xml_node_iterator::operator++()
	{
		assert(_wrap._root);
		_wrap._root = _wrap._root->next_sibling;
		return *this;
	}

	PUGI_IMPL_FN xml_node_iterator xml_node_iterator::operator++(int)
	{
		xml_node_iterator temp = *this;
		++*this;
		return temp;
	}

	PUGI_IMPL_FN xml_node_iterator& xml_node_iterator::operator--()
	{
		_wrap = _wrap._root ? _wrap.previous_sibling() : _parent.last_child();
		return *this;
	}

	PUGI_IMPL_FN xml_node_iterator xml_node_iterator::operator--(int)
	{
		xml_node_iterator temp = *this;
		--*this;
		return temp;
	}

	PUGI_IMPL_FN xml_attribute_iterator::xml_attribute_iterator()
	{
	}

	PUGI_IMPL_FN xml_attribute_iterator::xml_attribute_iterator(const xml_attribute& attr, const xml_node& parent): _wrap(attr), _parent(parent)
	{
	}

	PUGI_IMPL_FN xml_attribute_iterator::xml_attribute_iterator(xml_attribute_struct* ref, xml_node_struct* parent): _wrap(ref), _parent(parent)
	{
	}

	PUGI_IMPL_FN bool xml_attribute_iterator::operator==(const xml_attribute_iterator& rhs) const
	{
		return _wrap._attr == rhs._wrap._attr && _parent._root == rhs._parent._root;
	}

	PUGI_IMPL_FN bool xml_attribute_iterator::operator!=(const xml_attribute_iterator& rhs) const
	{
		return _wrap._attr != rhs._wrap._attr || _parent._root != rhs._parent._root;
	}

	PUGI_IMPL_FN xml_attribute& xml_attribute_iterator::operator*() const
	{
		assert(_wrap._attr);
		return _wrap;
	}

	PUGI_IMPL_FN xml_attribute* xml_attribute_iterator::operator->() const
	{
		assert(_wrap._attr);
		return const_cast<xml_attribute*>(&_wrap); // BCC5 workaround
	}

	PUGI_IMPL_FN xml_attribute_iterator& xml_attribute_iterator::operator++()
	{
		assert(_wrap._attr);
		_wrap._attr = _wrap._attr->next_attribute;
		return *this;
	}

	PUGI_IMPL_FN xml_attribute_iterator xml_attribute_iterator::operator++(int)
	{
		xml_attribute_iterator temp = *this;
		++*this;
		return temp;
	}

	PUGI_IMPL_FN xml_attribute_iterator& xml_attribute_iterator::operator--()
	{
		_wrap = _wrap._attr ? _wrap.previous_attribute() : _parent.last_attribute();
		return *this;
	}

	PUGI_IMPL_FN xml_attribute_iterator xml_attribute_iterator::operator--(int)
	{
		xml_attribute_iterator temp = *this;
		--*this;
		return temp;
	}

	PUGI_IMPL_FN xml_named_node_iterator::xml_named_node_iterator(): _name(0)
	{
	}

	PUGI_IMPL_FN xml_named_node_iterator::xml_named_node_iterator(const xml_node& node, const char_t* name): _wrap(node), _parent(node.parent()), _name(name)
	{
	}

	PUGI_IMPL_FN xml_named_node_iterator::xml_named_node_iterator(xml_node_struct* ref, xml_node_struct* parent, const char_t* name): _wrap(ref), _parent(parent), _name(name)
	{
	}

	PUGI_IMPL_FN bool xml_named_node_iterator::operator==(const xml_named_node_iterator& rhs) const
	{
		return _wrap._root == rhs._wrap._root && _parent._root == rhs._parent._root;
	}

	PUGI_IMPL_FN bool xml_named_node_iterator::operator!=(const xml_named_node_iterator& rhs) const
	{
		return _wrap._root != rhs._wrap._root || _parent._root != rhs._parent._root;
	}

	PUGI_IMPL_FN xml_node& xml_named_node_iterator::operator*() const
	{
		assert(_wrap._root);
		return _wrap;
	}

	PUGI_IMPL_FN xml_node* xml_named_node_iterator::operator->() const
	{
		assert(_wrap._root);
		return const_cast<xml_node*>(&_wrap); // BCC5 workaround
	}

	PUGI_IMPL_FN xml_named_node_iterator& xml_named_node_iterator::operator++()
	{
		assert(_wrap._root);
		_wrap = _wrap.next_sibling(_name);
		return *this;
	}

	PUGI_IMPL_FN xml_named_node_iterator xml_named_node_iterator::operator++(int)
	{
		xml_named_node_iterator temp = *this;
		++*this;
		return temp;
	}

	PUGI_IMPL_FN xml_named_node_iterator& xml_named_node_iterator::operator--()
	{
		if (_wrap._root)
			_wrap = _wrap.previous_sibling(_name);
		else
		{
			_wrap = _parent.last_child();

			if (!impl::strequal(_wrap.name(), _name))
				_wrap = _wrap.previous_sibling(_name);
		}

		return *this;
	}

	PUGI_IMPL_FN xml_named_node_iterator xml_named_node_iterator::operator--(int)
	{
		xml_named_node_iterator temp = *this;
		--*this;
		return temp;
	}

	PUGI_IMPL_FN xml_parse_result::xml_parse_result(): status(status_internal_error), offset(0), encoding(encoding_auto)
	{
	}

	PUGI_IMPL_FN xml_parse_result::operator bool() const
	{
		return status == status_ok;
	}

	PUGI_IMPL_FN const char* xml_parse_result::description() const
	{
		switch (status)
		{
		case status_ok: return "No error";

		case status_file_not_found: return "File was not found";
		case status_io_error: return "Error reading from file/stream";
		case status_out_of_memory: return "Could not allocate memory";
		case status_internal_error: return "Internal error occurred";

		case status_unrecognized_tag: return "Could not determine tag type";

		case status_bad_pi: return "Error parsing document declaration/processing instruction";
		case status_bad_comment: return "Error parsing comment";
		case status_bad_cdata: return "Error parsing CDATA section";
		case status_bad_doctype: return "Error parsing document type declaration";
		case status_bad_pcdata: return "Error parsing PCDATA section";
		case status_bad_start_element: return "Error parsing start element tag";
		case status_bad_attribute: return "Error parsing element attribute";
		case status_bad_end_element: return "Error parsing end element tag";
		case status_end_element_mismatch: return "Start-end tags mismatch";

		case status_append_invalid_root: return "Unable to append nodes: root is not an element or document";

		case status_no_document_element: return "No document element found";

		default: return "Unknown error";
		}
	}

	PUGI_IMPL_FN xml_document::xml_document(): _buffer(0)
	{
		_create();
	}

	PUGI_IMPL_FN xml_document::~xml_document()
	{
		_destroy();
	}

#ifdef PUGIXML_HAS_MOVE
	PUGI_IMPL_FN xml_document::xml_document(xml_document&& rhs) PUGIXML_NOEXCEPT_IF_NOT_COMPACT: _buffer(0)
	{
		_create();
		_move(rhs);
	}

	PUGI_IMPL_FN xml_document& xml_document::operator=(xml_document&& rhs) PUGIXML_NOEXCEPT_IF_NOT_COMPACT
	{
		if (this == &rhs) return *this;

		_destroy();
		_create();
		_move(rhs);

		return *this;
	}
#endif

	PUGI_IMPL_FN void xml_document::reset()
	{
		_destroy();
		_create();
	}

	PUGI_IMPL_FN void xml_document::reset(const xml_document& proto)
	{
		reset();

		impl::node_copy_tree(_root, proto._root);
	}

	PUGI_IMPL_FN void xml_document::_create()
	{
		assert(!_root);

	#ifdef PUGIXML_COMPACT
		// space for page marker for the first page (uint32_t), rounded up to pointer size; assumes pointers are at least 32-bit
		const size_t page_offset = sizeof(void*);
	#else
		const size_t page_offset = 0;
	#endif

		// initialize sentinel page
		PUGI_IMPL_STATIC_ASSERT(sizeof(impl::xml_memory_page) + sizeof(impl::xml_document_struct) + page_offset <= sizeof(_memory));

		// prepare page structure
		impl::xml_memory_page* page = impl::xml_memory_page::construct(_memory);
		assert(page);

		page->busy_size = impl::xml_memory_page_size;

		// setup first page marker
	#ifdef PUGIXML_COMPACT
		// round-trip through void* to avoid 'cast increases required alignment of target type' warning
		page->compact_page_marker = reinterpret_cast<uint32_t*>(static_cast<void*>(reinterpret_cast<char*>(page) + sizeof(impl::xml_memory_page)));
		*page->compact_page_marker = sizeof(impl::xml_memory_page);
	#endif

		// allocate new root
		_root = new (reinterpret_cast<char*>(page) + sizeof(impl::xml_memory_page) + page_offset) impl::xml_document_struct(page);
		_root->prev_sibling_c = _root;

		// setup sentinel page
		page->allocator = static_cast<impl::xml_document_struct*>(_root);

		// setup hash table pointer in allocator
	#ifdef PUGIXML_COMPACT
		page->allocator->_hash = &static_cast<impl::xml_document_struct*>(_root)->hash;
	#endif

		// verify the document allocation
		assert(reinterpret_cast<char*>(_root) + sizeof(impl::xml_document_struct) <= _memory + sizeof(_memory));
	}

	PUGI_IMPL_FN void xml_document::_destroy()
	{
		assert(_root);

		// destroy static storage
		if (_buffer)
		{
			impl::xml_memory::deallocate(_buffer);
			_buffer = 0;
		}

		// destroy extra buffers (note: no need to destroy linked list nodes, they're allocated using document allocator)
		for (impl::xml_extra_buffer* extra = static_cast<impl::xml_document_struct*>(_root)->extra_buffers; extra; extra = extra->next)
		{
			if (extra->buffer) impl::xml_memory::deallocate(extra->buffer);
		}

		// destroy dynamic storage, leave sentinel page (it's in static memory)
		impl::xml_memory_page* root_page = PUGI_IMPL_GETPAGE(_root);
		assert(root_page && !root_page->prev);
		assert(reinterpret_cast<char*>(root_page) >= _memory && reinterpret_cast<char*>(root_page) < _memory + sizeof(_memory));

		for (impl::xml_memory_page* page = root_page->next; page; )
		{
			impl::xml_memory_page* next = page->next;

			impl::xml_allocator::deallocate_page(page);

			page = next;
		}

	#ifdef PUGIXML_COMPACT
		// destroy hash table
		static_cast<impl::xml_document_struct*>(_root)->hash.clear();
	#endif

		_root = 0;
	}

#ifdef PUGIXML_HAS_MOVE
	PUGI_IMPL_FN void xml_document::_move(xml_document& rhs) PUGIXML_NOEXCEPT_IF_NOT_COMPACT
	{
		impl::xml_document_struct* doc = static_cast<impl::xml_document_struct*>(_root);
		impl::xml_document_struct* other = static_cast<impl::xml_document_struct*>(rhs._root);

		// save first child pointer for later; this needs hash access
		xml_node_struct* other_first_child = other->first_child;

	#ifdef PUGIXML_COMPACT
		// reserve space for the hash table up front; this is the only operation that can fail
		// if it does, we have no choice but to throw (if we have exceptions)
		if (other_first_child)
		{
			size_t other_children = 0;
			for (xml_node_struct* node = other_first_child; node; node = node->next_sibling)
				other_children++;

			// in compact mode, each pointer assignment could result in a hash table request
			// during move, we have to relocate document first_child and parents of all children
			// normally there's just one child and its parent has a pointerless encoding but
			// we assume the worst here
			if (!other->_hash->reserve(other_children + 1))
			{
			#ifdef PUGIXML_NO_EXCEPTIONS
				return;
			#else
				throw std::bad_alloc();
			#endif
			}
		}
	#endif

		// move allocation state
		// note that other->_root may point to the embedded document page, in which case we should keep original (empty) state
		if (other->_root != PUGI_IMPL_GETPAGE(other))
		{
			doc->_root = other->_root;
			doc->_busy_size = other->_busy_size;
		}

		// move buffer state
		doc->buffer = other->buffer;
		doc->extra_buffers = other->extra_buffers;
		_buffer = rhs._buffer;

	#ifdef PUGIXML_COMPACT
		// move compact hash; note that the hash table can have pointers to other but they will be "inactive", similarly to nodes removed with remove_child
		doc->hash = other->hash;
		doc->_hash = &doc->hash;

		// make sure we don't access other hash up until the end when we reinitialize other document
		other->_hash = 0;
	#endif

		// move page structure
		impl::xml_memory_page* doc_page = PUGI_IMPL_GETPAGE(doc);
		assert(doc_page && !doc_page->prev && !doc_page->next);

		impl::xml_memory_page* other_page = PUGI_IMPL_GETPAGE(other);
		assert(other_page && !other_page->prev);

		// relink pages since root page is embedded into xml_document
		if (impl::xml_memory_page* page = other_page->next)
		{
			assert(page->prev == other_page);

			page->prev = doc_page;

			doc_page->next = page;
			other_page->next = 0;
		}

		// make sure pages point to the correct document state
		for (impl::xml_memory_page* page = doc_page->next; page; page = page->next)
		{
			assert(page->allocator == other);

			page->allocator = doc;

		#ifdef PUGIXML_COMPACT
			// this automatically migrates most children between documents and prevents ->parent assignment from allocating
			if (page->compact_shared_parent == other)
				page->compact_shared_parent = doc;
		#endif
		}

		// move tree structure
		assert(!doc->first_child);

		doc->first_child = other_first_child;

		for (xml_node_struct* node = other_first_child; node; node = node->next_sibling)
		{
		#ifdef PUGIXML_COMPACT
			// most children will have migrated when we reassigned compact_shared_parent
			assert(node->parent == other || node->parent == doc);

			node->parent = doc;
		#else
			assert(node->parent == other);
			node->parent = doc;
		#endif
		}

		// reset other document
		new (other) impl::xml_document_struct(PUGI_IMPL_GETPAGE(other));
		rhs._buffer = 0;
	}
#endif

#ifndef PUGIXML_NO_STL
	PUGI_IMPL_FN xml_parse_result xml_document::load(std::basic_istream<char, std::char_traits<char> >& stream, unsigned int options, xml_encoding encoding)
	{
		reset();

		return impl::load_stream_impl(static_cast<impl::xml_document_struct*>(_root), stream, options, encoding, &_buffer);
	}

	PUGI_IMPL_FN xml_parse_result xml_document::load(std::basic_istream<wchar_t, std::char_traits<wchar_t> >& stream, unsigned int options)
	{
		reset();

		return impl::load_stream_impl(static_cast<impl::xml_document_struct*>(_root), stream, options, encoding_wchar, &_buffer);
	}
#endif

	PUGI_IMPL_FN xml_parse_result xml_document::load_string(const char_t* contents, unsigned int options)
	{
		// Force native encoding (skip autodetection)
	#ifdef PUGIXML_WCHAR_MODE
		xml_encoding encoding = encoding_wchar;
	#else
		xml_encoding encoding = encoding_utf8;
	#endif

		return load_buffer(contents, impl::strlength(contents) * sizeof(char_t), options, encoding);
	}

	PUGI_IMPL_FN xml_parse_result xml_document::load(const char_t* contents, unsigned int options)
	{
		return load_string(contents, options);
	}

	PUGI_IMPL_FN xml_parse_result xml_document::load_file(const char* path_, unsigned int options, xml_encoding encoding)
	{
		reset();

		using impl::auto_deleter; // MSVC7 workaround
		auto_deleter<FILE> file(impl::open_file(path_, "rb"), impl::close_file);

		return impl::load_file_impl(static_cast<impl::xml_document_struct*>(_root), file.data, options, encoding, &_buffer);
	}

	PUGI_IMPL_FN xml_parse_result xml_document::load_file(const wchar_t* path_, unsigned int options, xml_encoding encoding)
	{
		reset();

		using impl::auto_deleter; // MSVC7 workaround
		auto_deleter<FILE> file(impl::open_file_wide(path_, L"rb"), impl::close_file);

		return impl::load_file_impl(static_cast<impl::xml_document_struct*>(_root), file.data, options, encoding, &_buffer);
	}

	PUGI_IMPL_FN xml_parse_result xml_document::load_buffer(const void* contents, size_t size, unsigned int options, xml_encoding encoding)
	{
		reset();

		return impl::load_buffer_impl(static_cast<impl::xml_document_struct*>(_root), _root, const_cast<void*>(contents), size, options, encoding, false, false, &_buffer);
	}

	PUGI_IMPL_FN xml_parse_result xml_document::load_buffer_inplace(void* contents, size_t size, unsigned int options, xml_encoding encoding)
	{
		reset();

		return impl::load_buffer_impl(static_cast<impl::xml_document_struct*>(_root), _root, contents, size, options, encoding, true, false, &_buffer);
	}

	PUGI_IMPL_FN xml_parse_result xml_document::load_buffer_inplace_own(void* contents, size_t size, unsigned int options, xml_encoding encoding)
	{
		reset();

		return impl::load_buffer_impl(static_cast<impl::xml_document_struct*>(_root), _root, contents, size, options, encoding, true, true, &_buffer);
	}

	PUGI_IMPL_FN void xml_document::save(xml_writer& writer, const char_t* indent, unsigned int flags, xml_encoding encoding) const
	{
		impl::xml_buffered_writer buffered_writer(writer, encoding);

		if ((flags & format_write_bom) && encoding != encoding_latin1)
		{
			// BOM always represents the codepoint U+FEFF, so just write it in native encoding
		#ifdef PUGIXML_WCHAR_MODE
			unsigned int bom = 0xfeff;
			buffered_writer.write(static_cast<wchar_t>(bom));
		#else
			buffered_writer.write('\xef', '\xbb', '\xbf');
		#endif
		}

		if (!(flags & format_no_declaration) && !impl::has_declaration(_root))
		{
			buffered_writer.write_string(PUGIXML_TEXT("<?xml version=\"1.0\""));
			if (encoding == encoding_latin1) buffered_writer.write_string(PUGIXML_TEXT(" encoding=\"ISO-8859-1\""));
			buffered_writer.write('?', '>');
			if (!(flags & format_raw)) buffered_writer.write('\n');
		}

		impl::node_output(buffered_writer, _root, indent, flags, 0);

		buffered_writer.flush();
	}

#ifndef PUGIXML_NO_STL
	PUGI_IMPL_FN void xml_document::save(std::basic_ostream<char, std::char_traits<char> >& stream, const char_t* indent, unsigned int flags, xml_encoding encoding) const
	{
		xml_writer_stream writer(stream);

		save(writer, indent, flags, encoding);
	}

	PUGI_IMPL_FN void xml_document::save(std::basic_ostream<wchar_t, std::char_traits<wchar_t> >& stream, const char_t* indent, unsigned int flags) const
	{
		xml_writer_stream writer(stream);

		save(writer, indent, flags, encoding_wchar);
	}
#endif

	PUGI_IMPL_FN bool xml_document::save_file(const char* path_, const char_t* indent, unsigned int flags, xml_encoding encoding) const
	{
		using impl::auto_deleter; // MSVC7 workaround
		auto_deleter<FILE> file(impl::open_file(path_, (flags & format_save_file_text) ? "w" : "wb"), impl::close_file);

		return impl::save_file_impl(*this, file.data, indent, flags, encoding) && fclose(file.release()) == 0;
	}

	PUGI_IMPL_FN bool xml_document::save_file(const wchar_t* path_, const char_t* indent, unsigned int flags, xml_encoding encoding) const
	{
		using impl::auto_deleter; // MSVC7 workaround
		auto_deleter<FILE> file(impl::open_file_wide(path_, (flags & format_save_file_text) ? L"w" : L"wb"), impl::close_file);

		return impl::save_file_impl(*this, file.data, indent, flags, encoding) && fclose(file.release()) == 0;
	}

	PUGI_IMPL_FN xml_node xml_document::document_element() const
	{
		assert(_root);

		for (xml_node_struct* i = _root->first_child; i; i = i->next_sibling)
			if (PUGI_IMPL_NODETYPE(i) == node_element)
				return xml_node(i);

		return xml_node();
	}

#ifndef PUGIXML_NO_STL
	PUGI_IMPL_FN std::string PUGIXML_FUNCTION as_utf8(const wchar_t* str)
	{
		assert(str);

		return impl::as_utf8_impl(str, impl::strlength_wide(str));
	}

	PUGI_IMPL_FN std::string PUGIXML_FUNCTION as_utf8(const std::basic_string<wchar_t>& str)
	{
		return impl::as_utf8_impl(str.c_str(), str.size());
	}

	PUGI_IMPL_FN std::basic_string<wchar_t> PUGIXML_FUNCTION as_wide(const char* str)
	{
		assert(str);

		return impl::as_wide_impl(str, strlen(str));
	}

	PUGI_IMPL_FN std::basic_string<wchar_t> PUGIXML_FUNCTION as_wide(const std::string& str)
	{
		return impl::as_wide_impl(str.c_str(), str.size());
	}
#endif

	PUGI_IMPL_FN void PUGIXML_FUNCTION set_memory_management_functions(allocation_function allocate, deallocation_function deallocate)
	{
		impl::xml_memory::allocate = allocate;
		impl::xml_memory::deallocate = deallocate;
	}

	PUGI_IMPL_FN allocation_function PUGIXML_FUNCTION get_memory_allocation_function()
	{
		return impl::xml_memory::allocate;
	}

	PUGI_IMPL_FN deallocation_function PUGIXML_FUNCTION get_memory_deallocation_function()
	{
		return impl::xml_memory::deallocate;
	}
}

#if !defined(PUGIXML_NO_STL) && (defined(_MSC_VER) || defined(__ICC))
namespace std
{
	// Workarounds for (non-standard) iterator category detection for older versions (MSVC7/IC8 and earlier)
	PUGI_IMPL_FN std::bidirectional_iterator_tag _Iter_cat(const pugi::xml_node_iterator&)
	{
		return std::bidirectional_iterator_tag();
	}

	PUGI_IMPL_FN std::bidirectional_iterator_tag _Iter_cat(const pugi::xml_attribute_iterator&)
	{
		return std::bidirectional_iterator_tag();
	}

	PUGI_IMPL_FN std::bidirectional_iterator_tag _Iter_cat(const pugi::xml_named_node_iterator&)
	{
		return std::bidirectional_iterator_tag();
	}
}
#endif

#if !defined(PUGIXML_NO_STL) && defined(__SUNPRO_CC)
namespace std
{
	// Workarounds for (non-standard) iterator category detection
	PUGI_IMPL_FN std::bidirectional_iterator_tag __iterator_category(const pugi::xml_node_iterator&)
	{
		return std::bidirectional_iterator_tag();
	}

	PUGI_IMPL_FN std::bidirectional_iterator_tag __iterator_category(const pugi::xml_attribute_iterator&)
	{
		return std::bidirectional_iterator_tag();
	}

	PUGI_IMPL_FN std::bidirectional_iterator_tag __iterator_category(const pugi::xml_named_node_iterator&)
	{
		return std::bidirectional_iterator_tag();
	}
}
#endif

#ifndef PUGIXML_NO_XPATH
// STL replacements
PUGI_IMPL_NS_BEGIN
	struct equal_to
	{
		template <typename T> bool operator()(const T& lhs, const T& rhs) const
		{
			return lhs == rhs;
		}
	};

	struct not_equal_to
	{
		template <typename T> bool operator()(const T& lhs, const T& rhs) const
		{
			return lhs != rhs;
		}
	};

	struct less
	{
		template <typename T> bool operator()(const T& lhs, const T& rhs) const
		{
			return lhs < rhs;
		}
	};

	struct less_equal
	{
		template <typename T> bool operator()(const T& lhs, const T& rhs) const
		{
			return lhs <= rhs;
		}
	};

	template <typename T> inline void swap(T& lhs, T& rhs)
	{
		T temp = lhs;
		lhs = rhs;
		rhs = temp;
	}

	template <typename I, typename Pred> PUGI_IMPL_FN I min_element(I begin, I end, const Pred& pred)
	{
		I result = begin;

		for (I it = begin + 1; it != end; ++it)
			if (pred(*it, *result))
				result = it;

		return result;
	}

	template <typename I> PUGI_IMPL_FN void reverse(I begin, I end)
	{
		while (end - begin > 1)
			swap(*begin++, *--end);
	}

	template <typename I> PUGI_IMPL_FN I unique(I begin, I end)
	{
		// fast skip head
		while (end - begin > 1 && *begin != *(begin + 1))
			begin++;

		if (begin == end)
			return begin;

		// last written element
		I write = begin++;

		// merge unique elements
		while (begin != end)
		{
			if (*begin != *write)
				*++write = *begin++;
			else
				begin++;
		}

		// past-the-end (write points to live element)
		return write + 1;
	}

	template <typename T, typename Pred> PUGI_IMPL_FN void insertion_sort(T* begin, T* end, const Pred& pred)
	{
		if (begin == end)
			return;

		for (T* it = begin + 1; it != end; ++it)
		{
			T val = *it;
			T* hole = it;

			// move hole backwards
			while (hole > begin && pred(val, *(hole - 1)))
			{
				*hole = *(hole - 1);
				hole--;
			}

			// fill hole with element
			*hole = val;
		}
	}

	template <typename I, typename Pred> inline I median3(I first, I middle, I last, const Pred& pred)
	{
		if (pred(*middle, *first))
			swap(middle, first);
		if (pred(*last, *middle))
			swap(last, middle);
		if (pred(*middle, *first))
			swap(middle, first);

		return middle;
	}

	template <typename T, typename Pred> PUGI_IMPL_FN void partition3(T* begin, T* end, T pivot, const Pred& pred, T** out_eqbeg, T** out_eqend)
	{
		// invariant: array is split into 4 groups: = < ? > (each variable denotes the boundary between the groups)
		T* eq = begin;
		T* lt = begin;
		T* gt = end;

		while (lt < gt)
		{
			if (pred(*lt, pivot))
				lt++;
			else if (*lt == pivot)
				swap(*eq++, *lt++);
			else
				swap(*lt, *--gt);
		}

		// we now have just 4 groups: = < >; move equal elements to the middle
		T* eqbeg = gt;

		for (T* it = begin; it != eq; ++it)
			swap(*it, *--eqbeg);

		*out_eqbeg = eqbeg;
		*out_eqend = gt;
	}

	template <typename I, typename Pred> PUGI_IMPL_FN void sort(I begin, I end, const Pred& pred)
	{
		// sort large chunks
		while (end - begin > 16)
		{
			// find median element
			I middle = begin + (end - begin) / 2;
			I median = median3(begin, middle, end - 1, pred);

			// partition in three chunks (< = >)
			I eqbeg, eqend;
			partition3(begin, end, *median, pred, &eqbeg, &eqend);

			// loop on larger half
			if (eqbeg - begin > end - eqend)
			{
				sort(eqend, end, pred);
				end = eqbeg;
			}
			else
			{
				sort(begin, eqbeg, pred);
				begin = eqend;
			}
		}

		// insertion sort small chunk
		insertion_sort(begin, end, pred);
	}

	PUGI_IMPL_FN bool hash_insert(const void** table, size_t size, const void* key)
	{
		assert(key);

		unsigned int h = static_cast<unsigned int>(reinterpret_cast<uintptr_t>(key));

		// MurmurHash3 32-bit finalizer
		h ^= h >> 16;
		h *= 0x85ebca6bu;
		h ^= h >> 13;
		h *= 0xc2b2ae35u;
		h ^= h >> 16;

		size_t hashmod = size - 1;
		size_t bucket = h & hashmod;

		for (size_t probe = 0; probe <= hashmod; ++probe)
		{
			if (table[bucket] == 0)
			{
				table[bucket] = key;
				return true;
			}

			if (table[bucket] == key)
				return false;

			// hash collision, quadratic probing
			bucket = (bucket + probe + 1) & hashmod;
		}

		assert(false && "Hash table is full"); // unreachable
		return false;
	}
PUGI_IMPL_NS_END

// Allocator used for AST and evaluation stacks
PUGI_IMPL_NS_BEGIN
	static const size_t xpath_memory_page_size =
	#ifdef PUGIXML_MEMORY_XPATH_PAGE_SIZE
		PUGIXML_MEMORY_XPATH_PAGE_SIZE
	#else
		4096
	#endif
		;

	static const uintptr_t xpath_memory_block_alignment = sizeof(double) > sizeof(void*) ? sizeof(double) : sizeof(void*);

	struct xpath_memory_block
	{
		xpath_memory_block* next;
		size_t capacity;

		union
		{
			char data[xpath_memory_page_size];
			double alignment;
		};
	};

	struct xpath_allocator
	{
		xpath_memory_block* _root;
		size_t _root_size;
		bool* _error;

		xpath_allocator(xpath_memory_block* root, bool* error = 0): _root(root), _root_size(0), _error(error)
		{
		}

		void* allocate(size_t size)
		{
			// round size up to block alignment boundary
			size = (size + xpath_memory_block_alignment - 1) & ~(xpath_memory_block_alignment - 1);

			if (_root_size + size <= _root->capacity)
			{
				void* buf = &_root->data[0] + _root_size;
				_root_size += size;
				return buf;
			}
			else
			{
				// make sure we have at least 1/4th of the page free after allocation to satisfy subsequent allocation requests
				size_t block_capacity_base = sizeof(_root->data);
				size_t block_capacity_req = size + block_capacity_base / 4;
				size_t block_capacity = (block_capacity_base > block_capacity_req) ? block_capacity_base : block_capacity_req;

				size_t block_size = block_capacity + offsetof(xpath_memory_block, data);

				xpath_memory_block* block = static_cast<xpath_memory_block*>(xml_memory::allocate(block_size));
				if (!block)
				{
					if (_error) *_error = true;
					return 0;
				}

				block->next = _root;
				block->capacity = block_capacity;

				_root = block;
				_root_size = size;

				return block->data;
			}
		}

		void* reallocate(void* ptr, size_t old_size, size_t new_size)
		{
			// round size up to block alignment boundary
			old_size = (old_size + xpath_memory_block_alignment - 1) & ~(xpath_memory_block_alignment - 1);
			new_size = (new_size + xpath_memory_block_alignment - 1) & ~(xpath_memory_block_alignment - 1);

			// we can only reallocate the last object
			assert(ptr == 0 || static_cast<char*>(ptr) + old_size == &_root->data[0] + _root_size);

			// try to reallocate the object inplace
			if (ptr && _root_size - old_size + new_size <= _root->capacity)
			{
				_root_size = _root_size - old_size + new_size;
				return ptr;
			}

			// allocate a new block
			void* result = allocate(new_size);
			if (!result) return 0;

			// we have a new block
			if (ptr)
			{
				// copy old data (we only support growing)
				assert(new_size >= old_size);
				memcpy(result, ptr, old_size);

				// free the previous page if it had no other objects
				assert(_root->data == result);
				assert(_root->next);

				if (_root->next->data == ptr)
				{
					// deallocate the whole page, unless it was the first one
					xpath_memory_block* next = _root->next->next;

					if (next)
					{
						xml_memory::deallocate(_root->next);
						_root->next = next;
					}
				}
			}

			return result;
		}

		void revert(const xpath_allocator& state)
		{
			// free all new pages
			xpath_memory_block* cur = _root;

			while (cur != state._root)
			{
				xpath_memory_block* next = cur->next;

				xml_memory::deallocate(cur);

				cur = next;
			}

			// restore state
			_root = state._root;
			_root_size = state._root_size;
		}

		void release()
		{
			xpath_memory_block* cur = _root;
			assert(cur);

			while (cur->next)
			{
				xpath_memory_block* next = cur->next;

				xml_memory::deallocate(cur);

				cur = next;
			}
		}
	};

	struct xpath_allocator_capture
	{
		xpath_allocator_capture(xpath_allocator* alloc): _target(alloc), _state(*alloc)
		{
		}

		~xpath_allocator_capture()
		{
			_target->revert(_state);
		}

		xpath_allocator* _target;
		xpath_allocator _state;
	};

	struct xpath_stack
	{
		xpath_allocator* result;
		xpath_allocator* temp;
	};

	struct xpath_stack_data
	{
		xpath_memory_block blocks[2];
		xpath_allocator result;
		xpath_allocator temp;
		xpath_stack stack;
		bool oom;

		xpath_stack_data(): result(blocks + 0, &oom), temp(blocks + 1, &oom), oom(false)
		{
			blocks[0].next = blocks[1].next = 0;
			blocks[0].capacity = blocks[1].capacity = sizeof(blocks[0].data);

			stack.result = &result;
			stack.temp = &temp;
		}

		~xpath_stack_data()
		{
			result.release();
			temp.release();
		}
	};
PUGI_IMPL_NS_END

// String class
PUGI_IMPL_NS_BEGIN
	class xpath_string
	{
		const char_t* _buffer;
		bool _uses_heap;
		size_t _length_heap;

		static char_t* duplicate_string(const char_t* string, size_t length, xpath_allocator* alloc)
		{
			char_t* result = static_cast<char_t*>(alloc->allocate((length + 1) * sizeof(char_t)));
			if (!result) return 0;

			memcpy(result, string, length * sizeof(char_t));
			result[length] = 0;

			return result;
		}

		xpath_string(const char_t* buffer, bool uses_heap_, size_t length_heap): _buffer(buffer), _uses_heap(uses_heap_), _length_heap(length_heap)
		{
		}

	public:
		static xpath_string from_const(const char_t* str)
		{
			return xpath_string(str, false, 0);
		}

		static xpath_string from_heap_preallocated(const char_t* begin, const char_t* end)
		{
			assert(begin <= end && *end == 0);

			return xpath_string(begin, true, static_cast<size_t>(end - begin));
		}

		static xpath_string from_heap(const char_t* begin, const char_t* end, xpath_allocator* alloc)
		{
			assert(begin <= end);

			if (begin == end)
				return xpath_string();

			size_t length = static_cast<size_t>(end - begin);
			const char_t* data = duplicate_string(begin, length, alloc);

			return data ? xpath_string(data, true, length) : xpath_string();
		}

		xpath_string(): _buffer(PUGIXML_TEXT("")), _uses_heap(false), _length_heap(0)
		{
		}

		void append(const xpath_string& o, xpath_allocator* alloc)
		{
			// skip empty sources
			if (!*o._buffer) return;

			// fast append for constant empty target and constant source
			if (!*_buffer && !_uses_heap && !o._uses_heap)
			{
				_buffer = o._buffer;
			}
			else
			{
				// need to make heap copy
				size_t target_length = length();
				size_t source_length = o.length();
				size_t result_length = target_length + source_length;

				// allocate new buffer
				char_t* result = static_cast<char_t*>(alloc->reallocate(_uses_heap ? const_cast<char_t*>(_buffer) : 0, (target_length + 1) * sizeof(char_t), (result_length + 1) * sizeof(char_t)));
				if (!result) return;

				// append first string to the new buffer in case there was no reallocation
				if (!_uses_heap) memcpy(result, _buffer, target_length * sizeof(char_t));

				// append second string to the new buffer
				memcpy(result + target_length, o._buffer, source_length * sizeof(char_t));
				result[result_length] = 0;

				// finalize
				_buffer = result;
				_uses_heap = true;
				_length_heap = result_length;
			}
		}

		const char_t* c_str() const
		{
			return _buffer;
		}

		size_t length() const
		{
			return _uses_heap ? _length_heap : strlength(_buffer);
		}

		char_t* data(xpath_allocator* alloc)
		{
			// make private heap copy
			if (!_uses_heap)
			{
				size_t length_ = strlength(_buffer);
				const char_t* data_ = duplicate_string(_buffer, length_, alloc);

				if (!data_) return 0;

				_buffer = data_;
				_uses_heap = true;
				_length_heap = length_;
			}

			return const_cast<char_t*>(_buffer);
		}

		bool empty() const
		{
			return *_buffer == 0;
		}

		bool operator==(const xpath_string& o) const
		{
			return strequal(_buffer, o._buffer);
		}

		bool operator!=(const xpath_string& o) const
		{
			return !strequal(_buffer, o._buffer);
		}

		bool uses_heap() const
		{
			return _uses_heap;
		}
	};
PUGI_IMPL_NS_END

PUGI_IMPL_NS_BEGIN
	PUGI_IMPL_FN bool starts_with(const char_t* string, const char_t* pattern)
	{
		while (*pattern && *string == *pattern)
		{
			string++;
			pattern++;
		}

		return *pattern == 0;
	}

	PUGI_IMPL_FN const char_t* find_char(const char_t* s, char_t c)
	{
	#ifdef PUGIXML_WCHAR_MODE
		return wcschr(s, c);
	#else
		return strchr(s, c);
	#endif
	}

	PUGI_IMPL_FN const char_t* find_substring(const char_t* s, const char_t* p)
	{
	#ifdef PUGIXML_WCHAR_MODE
		// MSVC6 wcsstr bug workaround (if s is empty it always returns 0)
		return (*p == 0) ? s : wcsstr(s, p);
	#else
		return strstr(s, p);
	#endif
	}

	// Converts symbol to lower case, if it is an ASCII one
	PUGI_IMPL_FN char_t tolower_ascii(char_t ch)
	{
		return static_cast<unsigned int>(ch - 'A') < 26 ? static_cast<char_t>(ch | ' ') : ch;
	}

	PUGI_IMPL_FN xpath_string string_value(const xpath_node& na, xpath_allocator* alloc)
	{
		if (na.attribute())
			return xpath_string::from_const(na.attribute().value());
		else
		{
			xml_node n = na.node();

			switch (n.type())
			{
			case node_pcdata:
			case node_cdata:
			case node_comment:
			case node_pi:
				return xpath_string::from_const(n.value());

			case node_document:
			case node_element:
			{
				xpath_string result;

				// element nodes can have value if parse_embed_pcdata was used
				if (n.value()[0])
					result.append(xpath_string::from_const(n.value()), alloc);

				xml_node cur = n.first_child();

				while (cur && cur != n)
				{
					if (cur.type() == node_pcdata || cur.type() == node_cdata)
						result.append(xpath_string::from_const(cur.value()), alloc);

					if (cur.first_child())
						cur = cur.first_child();
					else if (cur.next_sibling())
						cur = cur.next_sibling();
					else
					{
						while (!cur.next_sibling() && cur != n)
							cur = cur.parent();

						if (cur != n) cur = cur.next_sibling();
					}
				}

				return result;
			}

			default:
				return xpath_string();
			}
		}
	}

	PUGI_IMPL_FN bool node_is_before_sibling(xml_node_struct* ln, xml_node_struct* rn)
	{
		assert(ln->parent == rn->parent);

		// there is no common ancestor (the shared parent is null), nodes are from different documents
		if (!ln->parent) return ln < rn;

		// determine sibling order
		xml_node_struct* ls = ln;
		xml_node_struct* rs = rn;

		while (ls && rs)
		{
			if (ls == rn) return true;
			if (rs == ln) return false;

			ls = ls->next_sibling;
			rs = rs->next_sibling;
		}

		// if rn sibling chain ended ln must be before rn
		return !rs;
	}

	PUGI_IMPL_FN bool node_is_before(xml_node_struct* ln, xml_node_struct* rn)
	{
		// find common ancestor at the same depth, if any
		xml_node_struct* lp = ln;
		xml_node_struct* rp = rn;

		while (lp && rp && lp->parent != rp->parent)
		{
			lp = lp->parent;
			rp = rp->parent;
		}

		// parents are the same!
		if (lp && rp) return node_is_before_sibling(lp, rp);

		// nodes are at different depths, need to normalize heights
		bool left_higher = !lp;

		while (lp)
		{
			lp = lp->parent;
			ln = ln->parent;
		}

		while (rp)
		{
			rp = rp->parent;
			rn = rn->parent;
		}

		// one node is the ancestor of the other
		if (ln == rn) return left_higher;

		// find common ancestor... again
		while (ln->parent != rn->parent)
		{
			ln = ln->parent;
			rn = rn->parent;
		}

		return node_is_before_sibling(ln, rn);
	}

	PUGI_IMPL_FN bool node_is_ancestor(xml_node_struct* parent, xml_node_struct* node)
	{
		while (node && node != parent) node = node->parent;

		return parent && node == parent;
	}

	PUGI_IMPL_FN const void* document_buffer_order(const xpath_node& xnode)
	{
		xml_node_struct* node = xnode.node().internal_object();

		if (node)
		{
			if ((get_document(node).header & xml_memory_page_contents_shared_mask) == 0)
			{
				if (node->name && (node->header & impl::xml_memory_page_name_allocated_or_shared_mask) == 0) return node->name;
				if (node->value && (node->header & impl::xml_memory_page_value_allocated_or_shared_mask) == 0) return node->value;
			}

			return 0;
		}

		xml_attribute_struct* attr = xnode.attribute().internal_object();

		if (attr)
		{
			if ((get_document(attr).header & xml_memory_page_contents_shared_mask) == 0)
			{
				if ((attr->header & impl::xml_memory_page_name_allocated_or_shared_mask) == 0) return attr->name;
				if ((attr->header & impl::xml_memory_page_value_allocated_or_shared_mask) == 0) return attr->value;
			}

			return 0;
		}

		return 0;
	}

	struct document_order_comparator
	{
		bool operator()(const xpath_node& lhs, const xpath_node& rhs) const
		{
			// optimized document order based check
			const void* lo = document_buffer_order(lhs);
			const void* ro = document_buffer_order(rhs);

			if (lo && ro) return lo < ro;

			// slow comparison
			xml_node ln = lhs.node(), rn = rhs.node();

			// compare attributes
			if (lhs.attribute() && rhs.attribute())
			{
				// shared parent
				if (lhs.parent() == rhs.parent())
				{
					// determine sibling order
					for (xml_attribute a = lhs.attribute(); a; a = a.next_attribute())
						if (a == rhs.attribute())
							return true;

					return false;
				}

				// compare attribute parents
				ln = lhs.parent();
				rn = rhs.parent();
			}
			else if (lhs.attribute())
			{
				// attributes go after the parent element
				if (lhs.parent() == rhs.node()) return false;

				ln = lhs.parent();
			}
			else if (rhs.attribute())
			{
				// attributes go after the parent element
				if (rhs.parent() == lhs.node()) return true;

				rn = rhs.parent();
			}

			if (ln == rn) return false;

			if (!ln || !rn) return ln < rn;

			return node_is_before(ln.internal_object(), rn.internal_object());
		}
	};

	PUGI_IMPL_FN double gen_nan()
	{
	#if defined(__STDC_IEC_559__) || ((FLT_RADIX - 0 == 2) && (FLT_MAX_EXP - 0 == 128) && (FLT_MANT_DIG - 0 == 24))
		PUGI_IMPL_STATIC_ASSERT(sizeof(float) == sizeof(uint32_t));
		typedef uint32_t UI; // BCC5 workaround
		union { float f; UI i; } u;
		u.i = 0x7fc00000;
		return double(u.f);
	#else
		// fallback
		const volatile double zero = 0.0;
		return zero / zero;
	#endif
	}

	PUGI_IMPL_FN bool is_nan(double value)
	{
	#if defined(PUGI_IMPL_MSVC_CRT_VERSION) || defined(__BORLANDC__)
		return !!_isnan(value);
	#elif defined(fpclassify) && defined(FP_NAN)
		return fpclassify(value) == FP_NAN;
	#else
		// fallback
		const volatile double v = value;
		return v != v;
	#endif
	}

	PUGI_IMPL_FN const char_t* convert_number_to_string_special(double value)
	{
	#if defined(PUGI_IMPL_MSVC_CRT_VERSION) || defined(__BORLANDC__)
		if (_finite(value)) return (value == 0) ? PUGIXML_TEXT("0") : 0;
		if (_isnan(value)) return PUGIXML_TEXT("NaN");
		return value > 0 ? PUGIXML_TEXT("Infinity") : PUGIXML_TEXT("-Infinity");
	#elif defined(fpclassify) && defined(FP_NAN) && defined(FP_INFINITE) && defined(FP_ZERO)
		switch (fpclassify(value))
		{
		case FP_NAN:
			return PUGIXML_TEXT("NaN");

		case FP_INFINITE:
			return value > 0 ? PUGIXML_TEXT("Infinity") : PUGIXML_TEXT("-Infinity");

		case FP_ZERO:
			return PUGIXML_TEXT("0");

		default:
			return 0;
		}
	#else
		// fallback
		const volatile double v = value;

		if (v == 0) return PUGIXML_TEXT("0");
		if (v != v) return PUGIXML_TEXT("NaN");
		if (v * 2 == v) return value > 0 ? PUGIXML_TEXT("Infinity") : PUGIXML_TEXT("-Infinity");
		return 0;
	#endif
	}

	PUGI_IMPL_FN bool convert_number_to_boolean(double value)
	{
		return (value != 0 && !is_nan(value));
	}

	PUGI_IMPL_FN void truncate_zeros(char* begin, char* end)
	{
		while (begin != end && end[-1] == '0') end--;

		*end = 0;
	}

	// gets mantissa digits in the form of 0.xxxxx with 0. implied and the exponent
#if defined(PUGI_IMPL_MSVC_CRT_VERSION) && PUGI_IMPL_MSVC_CRT_VERSION >= 1400
	PUGI_IMPL_FN void convert_number_to_mantissa_exponent(double value, char (&buffer)[32], char** out_mantissa, int* out_exponent)
	{
		// get base values
		int sign, exponent;
		_ecvt_s(buffer, sizeof(buffer), value, DBL_DIG + 1, &exponent, &sign);

		// truncate redundant zeros
		truncate_zeros(buffer, buffer + strlen(buffer));

		// fill results
		*out_mantissa = buffer;
		*out_exponent = exponent;
	}
#else
	PUGI_IMPL_FN void convert_number_to_mantissa_exponent(double value, char (&buffer)[32], char** out_mantissa, int* out_exponent)
	{
		// get a scientific notation value with IEEE DBL_DIG decimals
		PUGI_IMPL_SNPRINTF(buffer, "%.*e", DBL_DIG, value);

		// get the exponent (possibly negative)
		char* exponent_string = strchr(buffer, 'e');
		assert(exponent_string);

		int exponent = atoi(exponent_string + 1);

		// extract mantissa string: skip sign
		char* mantissa = buffer[0] == '-' ? buffer + 1 : buffer;
		assert(mantissa[0] != '0' && (mantissa[1] == '.' || mantissa[1] == ','));

		// divide mantissa by 10 to eliminate integer part
		mantissa[1] = mantissa[0];
		mantissa++;
		exponent++;

		// remove extra mantissa digits and zero-terminate mantissa
		truncate_zeros(mantissa, exponent_string);

		// fill results
		*out_mantissa = mantissa;
		*out_exponent = exponent;
	}
#endif

	PUGI_IMPL_FN xpath_string convert_number_to_string(double value, xpath_allocator* alloc)
	{
		// try special number conversion
		const char_t* special = convert_number_to_string_special(value);
		if (special) return xpath_string::from_const(special);

		// get mantissa + exponent form
		char mantissa_buffer[32];

		char* mantissa;
		int exponent;
		convert_number_to_mantissa_exponent(value, mantissa_buffer, &mantissa, &exponent);

		// allocate a buffer of suitable length for the number
		size_t result_size = strlen(mantissa_buffer) + (exponent > 0 ? exponent : -exponent) + 4;
		char_t* result = static_cast<char_t*>(alloc->allocate(sizeof(char_t) * result_size));
		if (!result) return xpath_string();

		// make the number!
		char_t* s = result;

		// sign
		if (value < 0) *s++ = '-';

		// integer part
		if (exponent <= 0)
		{
			*s++ = '0';
		}
		else
		{
			while (exponent > 0)
			{
				assert(*mantissa == 0 || static_cast<unsigned int>(*mantissa - '0') <= 9);
				*s++ = *mantissa ? *mantissa++ : '0';
				exponent--;
			}
		}

		// fractional part
		if (*mantissa)
		{
			// decimal point
			*s++ = '.';

			// extra zeroes from negative exponent
			while (exponent < 0)
			{
				*s++ = '0';
				exponent++;
			}

			// extra mantissa digits
			while (*mantissa)
			{
				assert(static_cast<unsigned int>(*mantissa - '0') <= 9);
				*s++ = *mantissa++;
			}
		}

		// zero-terminate
		assert(s < result + result_size);
		*s = 0;

		return xpath_string::from_heap_preallocated(result, s);
	}

	PUGI_IMPL_FN bool check_string_to_number_format(const char_t* string)
	{
		// parse leading whitespace
		while (PUGI_IMPL_IS_CHARTYPE(*string, ct_space)) ++string;

		// parse sign
		if (*string == '-') ++string;

		if (!*string) return false;

		// if there is no integer part, there should be a decimal part with at least one digit
		if (!PUGI_IMPL_IS_CHARTYPEX(string[0], ctx_digit) && (string[0] != '.' || !PUGI_IMPL_IS_CHARTYPEX(string[1], ctx_digit))) return false;

		// parse integer part
		while (PUGI_IMPL_IS_CHARTYPEX(*string, ctx_digit)) ++string;

		// parse decimal part
		if (*string == '.')
		{
			++string;

			while (PUGI_IMPL_IS_CHARTYPEX(*string, ctx_digit)) ++string;
		}

		// parse trailing whitespace
		while (PUGI_IMPL_IS_CHARTYPE(*string, ct_space)) ++string;

		return *string == 0;
	}

	PUGI_IMPL_FN double convert_string_to_number(const char_t* string)
	{
		// check string format
		if (!check_string_to_number_format(string)) return gen_nan();

		// parse string
	#ifdef PUGIXML_WCHAR_MODE
		return wcstod(string, 0);
	#else
		return strtod(string, 0);
	#endif
	}

	PUGI_IMPL_FN bool convert_string_to_number_scratch(char_t (&buffer)[32], const char_t* begin, const char_t* end, double* out_result)
	{
		size_t length = static_cast<size_t>(end - begin);
		char_t* scratch = buffer;

		if (length >= sizeof(buffer) / sizeof(buffer[0]))
		{
			// need to make dummy on-heap copy
			scratch = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
			if (!scratch) return false;
		}

		// copy string to zero-terminated buffer and perform conversion
		memcpy(scratch, begin, length * sizeof(char_t));
		scratch[length] = 0;

		*out_result = convert_string_to_number(scratch);

		// free dummy buffer
		if (scratch != buffer) xml_memory::deallocate(scratch);

		return true;
	}

	PUGI_IMPL_FN double round_nearest(double value)
	{
		return floor(value + 0.5);
	}

	PUGI_IMPL_FN double round_nearest_nzero(double value)
	{
		// same as round_nearest, but returns -0 for [-0.5, -0]
		// ceil is used to differentiate between +0 and -0 (we return -0 for [-0.5, -0] and +0 for +0)
		return (value >= -0.5 && value <= 0) ? ceil(value) : floor(value + 0.5);
	}

	PUGI_IMPL_FN const char_t* qualified_name(const xpath_node& node)
	{
		return node.attribute() ? node.attribute().name() : node.node().name();
	}

	PUGI_IMPL_FN const char_t* local_name(const xpath_node& node)
	{
		const char_t* name = qualified_name(node);
		const char_t* p = find_char(name, ':');

		return p ? p + 1 : name;
	}

	struct namespace_uri_predicate
	{
		const char_t* prefix;
		size_t prefix_length;

		namespace_uri_predicate(const char_t* name)
		{
			const char_t* pos = find_char(name, ':');

			prefix = pos ? name : 0;
			prefix_length = pos ? static_cast<size_t>(pos - name) : 0;
		}

		bool operator()(xml_attribute a) const
		{
			const char_t* name = a.name();

			if (!starts_with(name, PUGIXML_TEXT("xmlns"))) return false;

			return prefix ? name[5] == ':' && strequalrange(name + 6, prefix, prefix_length) : name[5] == 0;
		}
	};

	PUGI_IMPL_FN const char_t* namespace_uri(xml_node node)
	{
		namespace_uri_predicate pred = node.name();

		xml_node p = node;

		while (p)
		{
			xml_attribute a = p.find_attribute(pred);

			if (a) return a.value();

			p = p.parent();
		}

		return PUGIXML_TEXT("");
	}

	PUGI_IMPL_FN const char_t* namespace_uri(xml_attribute attr, xml_node parent)
	{
		namespace_uri_predicate pred = attr.name();

		// Default namespace does not apply to attributes
		if (!pred.prefix) return PUGIXML_TEXT("");

		xml_node p = parent;

		while (p)
		{
			xml_attribute a = p.find_attribute(pred);

			if (a) return a.value();

			p = p.parent();
		}

		return PUGIXML_TEXT("");
	}

	PUGI_IMPL_FN const char_t* namespace_uri(const xpath_node& node)
	{
		return node.attribute() ? namespace_uri(node.attribute(), node.parent()) : namespace_uri(node.node());
	}

	PUGI_IMPL_FN char_t* normalize_space(char_t* buffer)
	{
		char_t* write = buffer;

		for (char_t* it = buffer; *it; )
		{
			char_t ch = *it++;

			if (PUGI_IMPL_IS_CHARTYPE(ch, ct_space))
			{
				// replace whitespace sequence with single space
				while (PUGI_IMPL_IS_CHARTYPE(*it, ct_space)) it++;

				// avoid leading spaces
				if (write != buffer) *write++ = ' ';
			}
			else *write++ = ch;
		}

		// remove trailing space
		if (write != buffer && PUGI_IMPL_IS_CHARTYPE(write[-1], ct_space)) write--;

		// zero-terminate
		*write = 0;

		return write;
	}

	PUGI_IMPL_FN char_t* translate(char_t* buffer, const char_t* from, const char_t* to, size_t to_length)
	{
		char_t* write = buffer;

		while (*buffer)
		{
			PUGI_IMPL_DMC_VOLATILE char_t ch = *buffer++;

			const char_t* pos = find_char(from, ch);

			if (!pos)
				*write++ = ch; // do not process
			else if (static_cast<size_t>(pos - from) < to_length)
				*write++ = to[pos - from]; // replace
		}

		// zero-terminate
		*write = 0;

		return write;
	}

	PUGI_IMPL_FN unsigned char* translate_table_generate(xpath_allocator* alloc, const char_t* from, const char_t* to)
	{
		unsigned char table[128] = {0};

		while (*from)
		{
			unsigned int fc = static_cast<unsigned int>(*from);
			unsigned int tc = static_cast<unsigned int>(*to);

			if (fc >= 128 || tc >= 128)
				return 0;

			// code=128 means "skip character"
			if (!table[fc])
				table[fc] = static_cast<unsigned char>(tc ? tc : 128);

			from++;
			if (tc) to++;
		}

		for (int i = 0; i < 128; ++i)
			if (!table[i])
				table[i] = static_cast<unsigned char>(i);

		void* result = alloc->allocate(sizeof(table));
		if (!result) return 0;

		memcpy(result, table, sizeof(table));

		return static_cast<unsigned char*>(result);
	}

	PUGI_IMPL_FN char_t* translate_table(char_t* buffer, const unsigned char* table)
	{
		char_t* write = buffer;

		while (*buffer)
		{
			char_t ch = *buffer++;
			unsigned int index = static_cast<unsigned int>(ch);

			if (index < 128)
			{
				unsigned char code = table[index];

				// code=128 means "skip character" (table size is 128 so 128 can be a special value)
				// this code skips these characters without extra branches
				*write = static_cast<char_t>(code);
				write += 1 - (code >> 7);
			}
			else
			{
				*write++ = ch;
			}
		}

		// zero-terminate
		*write = 0;

		return write;
	}

	inline bool is_xpath_attribute(const char_t* name)
	{
		return !(starts_with(name, PUGIXML_TEXT("xmlns")) && (name[5] == 0 || name[5] == ':'));
	}

	struct xpath_variable_boolean: xpath_variable
	{
		xpath_variable_boolean(): xpath_variable(xpath_type_boolean), value(false)
		{
		}

		bool value;
		char_t name[1];
	};

	struct xpath_variable_number: xpath_variable
	{
		xpath_variable_number(): xpath_variable(xpath_type_number), value(0)
		{
		}

		double value;
		char_t name[1];
	};

	struct xpath_variable_string: xpath_variable
	{
		xpath_variable_string(): xpath_variable(xpath_type_string), value(0)
		{
		}

		~xpath_variable_string()
		{
			if (value) xml_memory::deallocate(value);
		}

		char_t* value;
		char_t name[1];
	};

	struct xpath_variable_node_set: xpath_variable
	{
		xpath_variable_node_set(): xpath_variable(xpath_type_node_set)
		{
		}

		xpath_node_set value;
		char_t name[1];
	};

	static const xpath_node_set dummy_node_set;

	PUGI_IMPL_FN PUGI_IMPL_UNSIGNED_OVERFLOW unsigned int hash_string(const char_t* str)
	{
		// Jenkins one-at-a-time hash (http://en.wikipedia.org/wiki/Jenkins_hash_function#one-at-a-time)
		unsigned int result = 0;

		while (*str)
		{
			result += static_cast<unsigned int>(*str++);
			result += result << 10;
			result ^= result >> 6;
		}

		result += result << 3;
		result ^= result >> 11;
		result += result << 15;

		return result;
	}

	template <typename T> PUGI_IMPL_FN T* new_xpath_variable(const char_t* name)
	{
		size_t length = strlength(name);
		if (length == 0) return 0; // empty variable names are invalid

		// $$ we can't use offsetof(T, name) because T is non-POD, so we just allocate additional length characters
		void* memory = xml_memory::allocate(sizeof(T) + length * sizeof(char_t));
		if (!memory) return 0;

		T* result = new (memory) T();

		memcpy(result->name, name, (length + 1) * sizeof(char_t));

		return result;
	}

	PUGI_IMPL_FN xpath_variable* new_xpath_variable(xpath_value_type type, const char_t* name)
	{
		switch (type)
		{
		case xpath_type_node_set:
			return new_xpath_variable<xpath_variable_node_set>(name);

		case xpath_type_number:
			return new_xpath_variable<xpath_variable_number>(name);

		case xpath_type_string:
			return new_xpath_variable<xpath_variable_string>(name);

		case xpath_type_boolean:
			return new_xpath_variable<xpath_variable_boolean>(name);

		default:
			return 0;
		}
	}

	template <typename T> PUGI_IMPL_FN void delete_xpath_variable(T* var)
	{
		var->~T();
		xml_memory::deallocate(var);
	}

	PUGI_IMPL_FN void delete_xpath_variable(xpath_value_type type, xpath_variable* var)
	{
		switch (type)
		{
		case xpath_type_node_set:
			delete_xpath_variable(static_cast<xpath_variable_node_set*>(var));
			break;

		case xpath_type_number:
			delete_xpath_variable(static_cast<xpath_variable_number*>(var));
			break;

		case xpath_type_string:
			delete_xpath_variable(static_cast<xpath_variable_string*>(var));
			break;

		case xpath_type_boolean:
			delete_xpath_variable(static_cast<xpath_variable_boolean*>(var));
			break;

		default:
			assert(false && "Invalid variable type"); // unreachable
		}
	}

	PUGI_IMPL_FN bool copy_xpath_variable(xpath_variable* lhs, const xpath_variable* rhs)
	{
		switch (rhs->type())
		{
		case xpath_type_node_set:
			return lhs->set(static_cast<const xpath_variable_node_set*>(rhs)->value);

		case xpath_type_number:
			return lhs->set(static_cast<const xpath_variable_number*>(rhs)->value);

		case xpath_type_string:
			return lhs->set(static_cast<const xpath_variable_string*>(rhs)->value);

		case xpath_type_boolean:
			return lhs->set(static_cast<const xpath_variable_boolean*>(rhs)->value);

		default:
			assert(false && "Invalid variable type"); // unreachable
			return false;
		}
	}

	PUGI_IMPL_FN bool get_variable_scratch(char_t (&buffer)[32], xpath_variable_set* set, const char_t* begin, const char_t* end, xpath_variable** out_result)
	{
		size_t length = static_cast<size_t>(end - begin);
		char_t* scratch = buffer;

		if (length >= sizeof(buffer) / sizeof(buffer[0]))
		{
			// need to make dummy on-heap copy
			scratch = static_cast<char_t*>(xml_memory::allocate((length + 1) * sizeof(char_t)));
			if (!scratch) return false;
		}

		// copy string to zero-terminated buffer and perform lookup
		memcpy(scratch, begin, length * sizeof(char_t));
		scratch[length] = 0;

		*out_result = set->get(scratch);

		// free dummy buffer
		if (scratch != buffer) xml_memory::deallocate(scratch);

		return true;
	}
PUGI_IMPL_NS_END

// Internal node set class
PUGI_IMPL_NS_BEGIN
	PUGI_IMPL_FN xpath_node_set::type_t xpath_get_order(const xpath_node* begin, const xpath_node* end)
	{
		if (end - begin < 2)
			return xpath_node_set::type_sorted;

		document_order_comparator cmp;

		bool first = cmp(begin[0], begin[1]);

		for (const xpath_node* it = begin + 1; it + 1 < end; ++it)
			if (cmp(it[0], it[1]) != first)
				return xpath_node_set::type_unsorted;

		return first ? xpath_node_set::type_sorted : xpath_node_set::type_sorted_reverse;
	}

	PUGI_IMPL_FN xpath_node_set::type_t xpath_sort(xpath_node* begin, xpath_node* end, xpath_node_set::type_t type, bool rev)
	{
		xpath_node_set::type_t order = rev ? xpath_node_set::type_sorted_reverse : xpath_node_set::type_sorted;

		if (type == xpath_node_set::type_unsorted)
		{
			xpath_node_set::type_t sorted = xpath_get_order(begin, end);

			if (sorted == xpath_node_set::type_unsorted)
			{
				sort(begin, end, document_order_comparator());

				type = xpath_node_set::type_sorted;
			}
			else
				type = sorted;
		}

		if (type != order) reverse(begin, end);

		return order;
	}

	PUGI_IMPL_FN xpath_node xpath_first(const xpath_node* begin, const xpath_node* end, xpath_node_set::type_t type)
	{
		if (begin == end) return xpath_node();

		switch (type)
		{
		case xpath_node_set::type_sorted:
			return *begin;

		case xpath_node_set::type_sorted_reverse:
			return *(end - 1);

		case xpath_node_set::type_unsorted:
			return *min_element(begin, end, document_order_comparator());

		default:
			assert(false && "Invalid node set type"); // unreachable
			return xpath_node();
		}
	}

	class xpath_node_set_raw
	{
		xpath_node_set::type_t _type;

		xpath_node* _begin;
		xpath_node* _end;
		xpath_node* _eos;

	public:
		xpath_node_set_raw(): _type(xpath_node_set::type_unsorted), _begin(0), _end(0), _eos(0)
		{
		}

		xpath_node* begin() const
		{
			return _begin;
		}

		xpath_node* end() const
		{
			return _end;
		}

		bool empty() const
		{
			return _begin == _end;
		}

		size_t size() const
		{
			return static_cast<size_t>(_end - _begin);
		}

		xpath_node first() const
		{
			return xpath_first(_begin, _end, _type);
		}

		void push_back_grow(const xpath_node& node, xpath_allocator* alloc);

		void push_back(const xpath_node& node, xpath_allocator* alloc)
		{
			if (_end != _eos)
				*_end++ = node;
			else
				push_back_grow(node, alloc);
		}

		void append(const xpath_node* begin_, const xpath_node* end_, xpath_allocator* alloc)
		{
			if (begin_ == end_) return;

			size_t size_ = static_cast<size_t>(_end - _begin);
			size_t capacity = static_cast<size_t>(_eos - _begin);
			size_t count = static_cast<size_t>(end_ - begin_);

			if (size_ + count > capacity)
			{
				// reallocate the old array or allocate a new one
				xpath_node* data = static_cast<xpath_node*>(alloc->reallocate(_begin, capacity * sizeof(xpath_node), (size_ + count) * sizeof(xpath_node)));
				if (!data) return;

				// finalize
				_begin = data;
				_end = data + size_;
				_eos = data + size_ + count;
			}

			memcpy(_end, begin_, count * sizeof(xpath_node));
			_end += count;
		}

		void sort_do()
		{
			_type = xpath_sort(_begin, _end, _type, false);
		}

		void truncate(xpath_node* pos)
		{
			assert(_begin <= pos && pos <= _end);

			_end = pos;
		}

		void remove_duplicates(xpath_allocator* alloc)
		{
			if (_type == xpath_node_set::type_unsorted && _end - _begin > 2)
			{
				xpath_allocator_capture cr(alloc);

				size_t size_ = static_cast<size_t>(_end - _begin);

				size_t hash_size = 1;
				while (hash_size < size_ + size_ / 2) hash_size *= 2;

				const void** hash_data = static_cast<const void**>(alloc->allocate(hash_size * sizeof(void**)));
				if (!hash_data) return;

				memset(hash_data, 0, hash_size * sizeof(const void**));

				xpath_node* write = _begin;

				for (xpath_node* it = _begin; it != _end; ++it)
				{
					const void* attr = it->attribute().internal_object();
					const void* node = it->node().internal_object();
					const void* key = attr ? attr : node;

					if (key && hash_insert(hash_data, hash_size, key))
					{
						*write++ = *it;
					}
				}

				_end = write;
			}
			else
			{
				_end = unique(_begin, _end);
			}
		}

		xpath_node_set::type_t type() const
		{
			return _type;
		}

		void set_type(xpath_node_set::type_t value)
		{
			_type = value;
		}
	};

	PUGI_IMPL_FN_NO_INLINE void xpath_node_set_raw::push_back_grow(const xpath_node& node, xpath_allocator* alloc)
	{
		size_t capacity = static_cast<size_t>(_eos - _begin);

		// get new capacity (1.5x rule)
		size_t new_capacity = capacity + capacity / 2 + 1;

		// reallocate the old array or allocate a new one
		xpath_node* data = static_cast<xpath_node*>(alloc->reallocate(_begin, capacity * sizeof(xpath_node), new_capacity * sizeof(xpath_node)));
		if (!data) return;

		// finalize
		_begin = data;
		_end = data + capacity;
		_eos = data + new_capacity;

		// push
		*_end++ = node;
	}
PUGI_IMPL_NS_END

PUGI_IMPL_NS_BEGIN
	struct xpath_context
	{
		xpath_node n;
		size_t position, size;

		xpath_context(const xpath_node& n_, size_t position_, size_t size_): n(n_), position(position_), size(size_)
		{
		}
	};

	enum lexeme_t
	{
		lex_none = 0,
		lex_equal,
		lex_not_equal,
		lex_less,
		lex_greater,
		lex_less_or_equal,
		lex_greater_or_equal,
		lex_plus,
		lex_minus,
		lex_multiply,
		lex_union,
		lex_var_ref,
		lex_open_brace,
		lex_close_brace,
		lex_quoted_string,
		lex_number,
		lex_slash,
		lex_double_slash,
		lex_open_square_brace,
		lex_close_square_brace,
		lex_string,
		lex_comma,
		lex_axis_attribute,
		lex_dot,
		lex_double_dot,
		lex_double_colon,
		lex_eof
	};

	struct xpath_lexer_string
	{
		const char_t* begin;
		const char_t* end;

		xpath_lexer_string(): begin(0), end(0)
		{
		}

		bool operator==(const char_t* other) const
		{
			size_t length = static_cast<size_t>(end - begin);

			return strequalrange(other, begin, length);
		}
	};

	class xpath_lexer
	{
		const char_t* _cur;
		const char_t* _cur_lexeme_pos;
		xpath_lexer_string _cur_lexeme_contents;

		lexeme_t _cur_lexeme;

	public:
		explicit xpath_lexer(const char_t* query): _cur(query)
		{
			next();
		}

		const char_t* state() const
		{
			return _cur;
		}

		void next()
		{
			const char_t* cur = _cur;

			while (PUGI_IMPL_IS_CHARTYPE(*cur, ct_space)) ++cur;

			// save lexeme position for error reporting
			_cur_lexeme_pos = cur;

			switch (*cur)
			{
			case 0:
				_cur_lexeme = lex_eof;
				break;

			case '>':
				if (*(cur+1) == '=')
				{
					cur += 2;
					_cur_lexeme = lex_greater_or_equal;
				}
				else
				{
					cur += 1;
					_cur_lexeme = lex_greater;
				}
				break;

			case '<':
				if (*(cur+1) == '=')
				{
					cur += 2;
					_cur_lexeme = lex_less_or_equal;
				}
				else
				{
					cur += 1;
					_cur_lexeme = lex_less;
				}
				break;

			case '!':
				if (*(cur+1) == '=')
				{
					cur += 2;
					_cur_lexeme = lex_not_equal;
				}
				else
				{
					_cur_lexeme = lex_none;
				}
				break;

			case '=':
				cur += 1;
				_cur_lexeme = lex_equal;

				break;

			case '+':
				cur += 1;
				_cur_lexeme = lex_plus;

				break;

			case '-':
				cur += 1;
				_cur_lexeme = lex_minus;

				break;

			case '*':
				cur += 1;
				_cur_lexeme = lex_multiply;

				break;

			case '|':
				cur += 1;
				_cur_lexeme = lex_union;

				break;

			case '$':
				cur += 1;

				if (PUGI_IMPL_IS_CHARTYPEX(*cur, ctx_start_symbol))
				{
					_cur_lexeme_contents.begin = cur;

					while (PUGI_IMPL_IS_CHARTYPEX(*cur, ctx_symbol)) cur++;

					if (cur[0] == ':' && PUGI_IMPL_IS_CHARTYPEX(cur[1], ctx_symbol)) // qname
					{
						cur++; // :

						while (PUGI_IMPL_IS_CHARTYPEX(*cur, ctx_symbol)) cur++;
					}

					_cur_lexeme_contents.end = cur;

					_cur_lexeme = lex_var_ref;
				}
				else
				{
					_cur_lexeme = lex_none;
				}

				break;

			case '(':
				cur += 1;
				_cur_lexeme = lex_open_brace;

				break;

			case ')':
				cur += 1;
				_cur_lexeme = lex_close_brace;

				break;

			case '[':
				cur += 1;
				_cur_lexeme = lex_open_square_brace;

				break;

			case ']':
				cur += 1;
				_cur_lexeme = lex_close_square_brace;

				break;

			case ',':
				cur += 1;
				_cur_lexeme = lex_comma;

				break;

			case '/':
				if (*(cur+1) == '/')
				{
					cur += 2;
					_cur_lexeme = lex_double_slash;
				}
				else
				{
					cur += 1;
					_cur_lexeme = lex_slash;
				}
				break;

			case '.':
				if (*(cur+1) == '.')
				{
					cur += 2;
					_cur_lexeme = lex_double_dot;
				}
				else if (PUGI_IMPL_IS_CHARTYPEX(*(cur+1), ctx_digit))
				{
					_cur_lexeme_contents.begin = cur; // .

					++cur;

					while (PUGI_IMPL_IS_CHARTYPEX(*cur, ctx_digit)) cur++;

					_cur_lexeme_contents.end = cur;

					_cur_lexeme = lex_number;
				}
				else
				{
					cur += 1;
					_cur_lexeme = lex_dot;
				}
				break;

			case '@':
				cur += 1;
				_cur_lexeme = lex_axis_attribute;

				break;

			case '"':
			case '\'':
			{
				char_t terminator = *cur;

				++cur;

				_cur_lexeme_contents.begin = cur;
				while (*cur && *cur != terminator) cur++;
				_cur_lexeme_contents.end = cur;

				if (!*cur)
					_cur_lexeme = lex_none;
				else
				{
					cur += 1;
					_cur_lexeme = lex_quoted_string;
				}

				break;
			}

			case ':':
				if (*(cur+1) == ':')
				{
					cur += 2;
					_cur_lexeme = lex_double_colon;
				}
				else
				{
					_cur_lexeme = lex_none;
				}
				break;

			default:
				if (PUGI_IMPL_IS_CHARTYPEX(*cur, ctx_digit))
				{
					_cur_lexeme_contents.begin = cur;

					while (PUGI_IMPL_IS_CHARTYPEX(*cur, ctx_digit)) cur++;

					if (*cur == '.')
					{
						cur++;

						while (PUGI_IMPL_IS_CHARTYPEX(*cur, ctx_digit)) cur++;
					}

					_cur_lexeme_contents.end = cur;

					_cur_lexeme = lex_number;
				}
				else if (PUGI_IMPL_IS_CHARTYPEX(*cur, ctx_start_symbol))
				{
					_cur_lexeme_contents.begin = cur;

					while (PUGI_IMPL_IS_CHARTYPEX(*cur, ctx_symbol)) cur++;

					if (cur[0] == ':')
					{
						if (cur[1] == '*') // namespace test ncname:*
						{
							cur += 2; // :*
						}
						else if (PUGI_IMPL_IS_CHARTYPEX(cur[1], ctx_symbol)) // namespace test qname
						{
							cur++; // :

							while (PUGI_IMPL_IS_CHARTYPEX(*cur, ctx_symbol)) cur++;
						}
					}

					_cur_lexeme_contents.end = cur;

					_cur_lexeme = lex_string;
				}
				else
				{
					_cur_lexeme = lex_none;
				}
			}

			_cur = cur;
		}

		lexeme_t current() const
		{
			return _cur_lexeme;
		}

		const char_t* current_pos() const
		{
			return _cur_lexeme_pos;
		}

		const xpath_lexer_string& contents() const
		{
			assert(_cur_lexeme == lex_var_ref || _cur_lexeme == lex_number || _cur_lexeme == lex_string || _cur_lexeme == lex_quoted_string);

			return _cur_lexeme_contents;
		}
	};

	enum ast_type_t
	{
		ast_unknown,
		ast_op_or,						// left or right
		ast_op_and,						// left and right
		ast_op_equal,					// left = right
		ast_op_not_equal,				// left != right
		ast_op_less,					// left < right
		ast_op_greater,					// left > right
		ast_op_less_or_equal,			// left <= right
		ast_op_greater_or_equal,		// left >= right
		ast_op_add,						// left + right
		ast_op_subtract,				// left - right
		ast_op_multiply,				// left * right
		ast_op_divide,					// left / right
		ast_op_mod,						// left % right
		ast_op_negate,					// left - right
		ast_op_union,					// left | right
		ast_predicate,					// apply predicate to set; next points to next predicate
		ast_filter,						// select * from left where right
		ast_string_constant,			// string constant
		ast_number_constant,			// number constant
		ast_variable,					// variable
		ast_func_last,					// last()
		ast_func_position,				// position()
		ast_func_count,					// count(left)
		ast_func_id,					// id(left)
		ast_func_local_name_0,			// local-name()
		ast_func_local_name_1,			// local-name(left)
		ast_func_namespace_uri_0,		// namespace-uri()
		ast_func_namespace_uri_1,		// namespace-uri(left)
		ast_func_name_0,				// name()
		ast_func_name_1,				// name(left)
		ast_func_string_0,				// string()
		ast_func_string_1,				// string(left)
		ast_func_concat,				// concat(left, right, siblings)
		ast_func_starts_with,			// starts_with(left, right)
		ast_func_contains,				// contains(left, right)
		ast_func_substring_before,		// substring-before(left, right)
		ast_func_substring_after,		// substring-after(left, right)
		ast_func_substring_2,			// substring(left, right)
		ast_func_substring_3,			// substring(left, right, third)
		ast_func_string_length_0,		// string-length()
		ast_func_string_length_1,		// string-length(left)
		ast_func_normalize_space_0,		// normalize-space()
		ast_func_normalize_space_1,		// normalize-space(left)
		ast_func_translate,				// translate(left, right, third)
		ast_func_boolean,				// boolean(left)
		ast_func_not,					// not(left)
		ast_func_true,					// true()
		ast_func_false,					// false()
		ast_func_lang,					// lang(left)
		ast_func_number_0,				// number()
		ast_func_number_1,				// number(left)
		ast_func_sum,					// sum(left)
		ast_func_floor,					// floor(left)
		ast_func_ceiling,				// ceiling(left)
		ast_func_round,					// round(left)
		ast_step,						// process set left with step
		ast_step_root,					// select root node

		ast_opt_translate_table,		// translate(left, right, third) where right/third are constants
		ast_opt_compare_attribute		// @name = 'string'
	};

	enum axis_t
	{
		axis_ancestor,
		axis_ancestor_or_self,
		axis_attribute,
		axis_child,
		axis_descendant,
		axis_descendant_or_self,
		axis_following,
		axis_following_sibling,
		axis_namespace,
		axis_parent,
		axis_preceding,
		axis_preceding_sibling,
		axis_self
	};

	enum nodetest_t
	{
		nodetest_none,
		nodetest_name,
		nodetest_type_node,
		nodetest_type_comment,
		nodetest_type_pi,
		nodetest_type_text,
		nodetest_pi,
		nodetest_all,
		nodetest_all_in_namespace
	};

	enum predicate_t
	{
		predicate_default,
		predicate_posinv,
		predicate_constant,
		predicate_constant_one
	};

	enum nodeset_eval_t
	{
		nodeset_eval_all,
		nodeset_eval_any,
		nodeset_eval_first
	};

	template <axis_t N> struct axis_to_type
	{
		static const axis_t axis;
	};

	template <axis_t N> const axis_t axis_to_type<N>::axis = N;

	class xpath_ast_node
	{
	private:
		// node type
		char _type;
		char _rettype;

		// for ast_step
		char _axis;

		// for ast_step/ast_predicate/ast_filter
		char _test;

		// tree node structure
		xpath_ast_node* _left;
		xpath_ast_node* _right;
		xpath_ast_node* _next;

		union
		{
			// value for ast_string_constant
			const char_t* string;
			// value for ast_number_constant
			double number;
			// variable for ast_variable
			xpath_variable* variable;
			// node test for ast_step (node name/namespace/node type/pi target)
			const char_t* nodetest;
			// table for ast_opt_translate_table
			const unsigned char* table;
		} _data;

		xpath_ast_node(const xpath_ast_node&);
		xpath_ast_node& operator=(const xpath_ast_node&);

		template <class Comp> static bool compare_eq(xpath_ast_node* lhs, xpath_ast_node* rhs, const xpath_context& c, const xpath_stack& stack, const Comp& comp)
		{
			xpath_value_type lt = lhs->rettype(), rt = rhs->rettype();

			if (lt != xpath_type_node_set && rt != xpath_type_node_set)
			{
				if (lt == xpath_type_boolean || rt == xpath_type_boolean)
					return comp(lhs->eval_boolean(c, stack), rhs->eval_boolean(c, stack));
				else if (lt == xpath_type_number || rt == xpath_type_number)
					return comp(lhs->eval_number(c, stack), rhs->eval_number(c, stack));
				else if (lt == xpath_type_string || rt == xpath_type_string)
				{
					xpath_allocator_capture cr(stack.result);

					xpath_string ls = lhs->eval_string(c, stack);
					xpath_string rs = rhs->eval_string(c, stack);

					return comp(ls, rs);
				}
			}
			else if (lt == xpath_type_node_set && rt == xpath_type_node_set)
			{
				xpath_allocator_capture cr(stack.result);

				xpath_node_set_raw ls = lhs->eval_node_set(c, stack, nodeset_eval_all);
				xpath_node_set_raw rs = rhs->eval_node_set(c, stack, nodeset_eval_all);

				for (const xpath_node* li = ls.begin(); li != ls.end(); ++li)
					for (const xpath_node* ri = rs.begin(); ri != rs.end(); ++ri)
					{
						xpath_allocator_capture cri(stack.result);

						if (comp(string_value(*li, stack.result), string_value(*ri, stack.result)))
							return true;
					}

				return false;
			}
			else
			{
				if (lt == xpath_type_node_set)
				{
					swap(lhs, rhs);
					swap(lt, rt);
				}

				if (lt == xpath_type_boolean)
					return comp(lhs->eval_boolean(c, stack), rhs->eval_boolean(c, stack));
				else if (lt == xpath_type_number)
				{
					xpath_allocator_capture cr(stack.result);

					double l = lhs->eval_number(c, stack);
					xpath_node_set_raw rs = rhs->eval_node_set(c, stack, nodeset_eval_all);

					for (const xpath_node* ri = rs.begin(); ri != rs.end(); ++ri)
					{
						xpath_allocator_capture cri(stack.result);

						if (comp(l, convert_string_to_number(string_value(*ri, stack.result).c_str())))
							return true;
					}

					return false;
				}
				else if (lt == xpath_type_string)
				{
					xpath_allocator_capture cr(stack.result);

					xpath_string l = lhs->eval_string(c, stack);
					xpath_node_set_raw rs = rhs->eval_node_set(c, stack, nodeset_eval_all);

					for (const xpath_node* ri = rs.begin(); ri != rs.end(); ++ri)
					{
						xpath_allocator_capture cri(stack.result);

						if (comp(l, string_value(*ri, stack.result)))
							return true;
					}

					return false;
				}
			}

			assert(false && "Wrong types"); // unreachable
			return false;
		}

		static bool eval_once(xpath_node_set::type_t type, nodeset_eval_t eval)
		{
			return type == xpath_node_set::type_sorted ? eval != nodeset_eval_all : eval == nodeset_eval_any;
		}

		template <class Comp> static bool compare_rel(xpath_ast_node* lhs, xpath_ast_node* rhs, const xpath_context& c, const xpath_stack& stack, const Comp& comp)
		{
			xpath_value_type lt = lhs->rettype(), rt = rhs->rettype();

			if (lt != xpath_type_node_set && rt != xpath_type_node_set)
				return comp(lhs->eval_number(c, stack), rhs->eval_number(c, stack));
			else if (lt == xpath_type_node_set && rt == xpath_type_node_set)
			{
				xpath_allocator_capture cr(stack.result);

				xpath_node_set_raw ls = lhs->eval_node_set(c, stack, nodeset_eval_all);
				xpath_node_set_raw rs = rhs->eval_node_set(c, stack, nodeset_eval_all);

				for (const xpath_node* li = ls.begin(); li != ls.end(); ++li)
				{
					xpath_allocator_capture cri(stack.result);

					double l = convert_string_to_number(string_value(*li, stack.result).c_str());

					for (const xpath_node* ri = rs.begin(); ri != rs.end(); ++ri)
					{
						xpath_allocator_capture crii(stack.result);

						if (comp(l, convert_string_to_number(string_value(*ri, stack.result).c_str())))
							return true;
					}
				}

				return false;
			}
			else if (lt != xpath_type_node_set && rt == xpath_type_node_set)
			{
				xpath_allocator_capture cr(stack.result);

				double l = lhs->eval_number(c, stack);
				xpath_node_set_raw rs = rhs->eval_node_set(c, stack, nodeset_eval_all);

				for (const xpath_node* ri = rs.begin(); ri != rs.end(); ++ri)
				{
					xpath_allocator_capture cri(stack.result);

					if (comp(l, convert_string_to_number(string_value(*ri, stack.result).c_str())))
						return true;
				}

				return false;
			}
			else if (lt == xpath_type_node_set && rt != xpath_type_node_set)
			{
				xpath_allocator_capture cr(stack.result);

				xpath_node_set_raw ls = lhs->eval_node_set(c, stack, nodeset_eval_all);
				double r = rhs->eval_number(c, stack);

				for (const xpath_node* li = ls.begin(); li != ls.end(); ++li)
				{
					xpath_allocator_capture cri(stack.result);

					if (comp(convert_string_to_number(string_value(*li, stack.result).c_str()), r))
						return true;
				}

				return false;
			}
			else
			{
				assert(false && "Wrong types"); // unreachable
				return false;
			}
		}

		static void apply_predicate_boolean(xpath_node_set_raw& ns, size_t first, xpath_ast_node* expr, const xpath_stack& stack, bool once)
		{
			assert(ns.size() >= first);
			assert(expr->rettype() != xpath_type_number);

			size_t i = 1;
			size_t size = ns.size() - first;

			xpath_node* last = ns.begin() + first;

			// remove_if... or well, sort of
			for (xpath_node* it = last; it != ns.end(); ++it, ++i)
			{
				xpath_context c(*it, i, size);

				if (expr->eval_boolean(c, stack))
				{
					*last++ = *it;

					if (once) break;
				}
			}

			ns.truncate(last);
		}

		static void apply_predicate_number(xpath_node_set_raw& ns, size_t first, xpath_ast_node* expr, const xpath_stack& stack, bool once)
		{
			assert(ns.size() >= first);
			assert(expr->rettype() == xpath_type_number);

			size_t i = 1;
			size_t size = ns.size() - first;

			xpath_node* last = ns.begin() + first;

			// remove_if... or well, sort of
			for (xpath_node* it = last; it != ns.end(); ++it, ++i)
			{
				xpath_context c(*it, i, size);

				if (expr->eval_number(c, stack) == static_cast<double>(i))
				{
					*last++ = *it;

					if (once) break;
				}
			}

			ns.truncate(last);
		}

		static void apply_predicate_number_const(xpath_node_set_raw& ns, size_t first, xpath_ast_node* expr, const xpath_stack& stack)
		{
			assert(ns.size() >= first);
			assert(expr->rettype() == xpath_type_number);

			size_t size = ns.size() - first;

			xpath_node* last = ns.begin() + first;

			xpath_node cn;
			xpath_context c(cn, 1, size);

			double er = expr->eval_number(c, stack);

			if (er >= 1.0 && er <= static_cast<double>(size))
			{
				size_t eri = static_cast<size_t>(er);

				if (er == static_cast<double>(eri))
				{
					xpath_node r = last[eri - 1];

					*last++ = r;
				}
			}

			ns.truncate(last);
		}

		void apply_predicate(xpath_node_set_raw& ns, size_t first, const xpath_stack& stack, bool once)
		{
			if (ns.size() == first) return;

			assert(_type == ast_filter || _type == ast_predicate);

			if (_test == predicate_constant || _test == predicate_constant_one)
				apply_predicate_number_const(ns, first, _right, stack);
			else if (_right->rettype() == xpath_type_number)
				apply_predicate_number(ns, first, _right, stack, once);
			else
				apply_predicate_boolean(ns, first, _right, stack, once);
		}

		void apply_predicates(xpath_node_set_raw& ns, size_t first, const xpath_stack& stack, nodeset_eval_t eval)
		{
			if (ns.size() == first) return;

			bool last_once = eval_once(ns.type(), eval);

			for (xpath_ast_node* pred = _right; pred; pred = pred->_next)
				pred->apply_predicate(ns, first, stack, !pred->_next && last_once);
		}

		bool step_push(xpath_node_set_raw& ns, xml_attribute_struct* a, xml_node_struct* parent, xpath_allocator* alloc)
		{
			assert(a);

			const char_t* name = a->name ? a->name + 0 : PUGIXML_TEXT("");

			switch (_test)
			{
			case nodetest_name:
				if (strequal(name, _data.nodetest) && is_xpath_attribute(name))
				{
					ns.push_back(xpath_node(xml_attribute(a), xml_node(parent)), alloc);
					return true;
				}
				break;

			case nodetest_type_node:
			case nodetest_all:
				if (is_xpath_attribute(name))
				{
					ns.push_back(xpath_node(xml_attribute(a), xml_node(parent)), alloc);
					return true;
				}
				break;

			case nodetest_all_in_namespace:
				if (starts_with(name, _data.nodetest) && is_xpath_attribute(name))
				{
					ns.push_back(xpath_node(xml_attribute(a), xml_node(parent)), alloc);
					return true;
				}
				break;

			default:
				;
			}

			return false;
		}

		bool step_push(xpath_node_set_raw& ns, xml_node_struct* n, xpath_allocator* alloc)
		{
			assert(n);

			xml_node_type type = PUGI_IMPL_NODETYPE(n);

			switch (_test)
			{
			case nodetest_name:
				if (type == node_element && n->name && strequal(n->name, _data.nodetest))
				{
					ns.push_back(xml_node(n), alloc);
					return true;
				}
				break;

			case nodetest_type_node:
				ns.push_back(xml_node(n), alloc);
				return true;

			case nodetest_type_comment:
				if (type == node_comment)
				{
					ns.push_back(xml_node(n), alloc);
					return true;
				}
				break;

			case nodetest_type_text:
				if (type == node_pcdata || type == node_cdata)
				{
					ns.push_back(xml_node(n), alloc);
					return true;
				}
				break;

			case nodetest_type_pi:
				if (type == node_pi)
				{
					ns.push_back(xml_node(n), alloc);
					return true;
				}
				break;

			case nodetest_pi:
				if (type == node_pi && n->name && strequal(n->name, _data.nodetest))
				{
					ns.push_back(xml_node(n), alloc);
					return true;
				}
				break;

			case nodetest_all:
				if (type == node_element)
				{
					ns.push_back(xml_node(n), alloc);
					return true;
				}
				break;

			case nodetest_all_in_namespace:
				if (type == node_element && n->name && starts_with(n->name, _data.nodetest))
				{
					ns.push_back(xml_node(n), alloc);
					return true;
				}
				break;

			default:
				assert(false && "Unknown axis"); // unreachable
			}

			return false;
		}

		template <class T> void step_fill(xpath_node_set_raw& ns, xml_node_struct* n, xpath_allocator* alloc, bool once, T)
		{
			const axis_t axis = T::axis;

			switch (axis)
			{
			case axis_attribute:
			{
				for (xml_attribute_struct* a = n->first_attribute; a; a = a->next_attribute)
					if (step_push(ns, a, n, alloc) & once)
						return;

				break;
			}

			case axis_child:
			{
				for (xml_node_struct* c = n->first_child; c; c = c->next_sibling)
					if (step_push(ns, c, alloc) & once)
						return;

				break;
			}

			case axis_descendant:
			case axis_descendant_or_self:
			{
				if (axis == axis_descendant_or_self)
					if (step_push(ns, n, alloc) & once)
						return;

				xml_node_struct* cur = n->first_child;

				while (cur)
				{
					if (step_push(ns, cur, alloc) & once)
						return;

					if (cur->first_child)
						cur = cur->first_child;
					else
					{
						while (!cur->next_sibling)
						{
							cur = cur->parent;

							if (cur == n) return;
						}

						cur = cur->next_sibling;
					}
				}

				break;
			}

			case axis_following_sibling:
			{
				for (xml_node_struct* c = n->next_sibling; c; c = c->next_sibling)
					if (step_push(ns, c, alloc) & once)
						return;

				break;
			}

			case axis_preceding_sibling:
			{
				for (xml_node_struct* c = n->prev_sibling_c; c->next_sibling; c = c->prev_sibling_c)
					if (step_push(ns, c, alloc) & once)
						return;

				break;
			}

			case axis_following:
			{
				xml_node_struct* cur = n;

				// exit from this node so that we don't include descendants
				while (!cur->next_sibling)
				{
					cur = cur->parent;

					if (!cur) return;
				}

				cur = cur->next_sibling;

				while (cur)
				{
					if (step_push(ns, cur, alloc) & once)
						return;

					if (cur->first_child)
						cur = cur->first_child;
					else
					{
						while (!cur->next_sibling)
						{
							cur = cur->parent;

							if (!cur) return;
						}

						cur = cur->next_sibling;
					}
				}

				break;
			}

			case axis_preceding:
			{
				xml_node_struct* cur = n;

				// exit from this node so that we don't include descendants
				while (!cur->prev_sibling_c->next_sibling)
				{
					cur = cur->parent;

					if (!cur) return;
				}

				cur = cur->prev_sibling_c;

				while (cur)
				{
					if (cur->first_child)
						cur = cur->first_child->prev_sibling_c;
					else
					{
						// leaf node, can't be ancestor
						if (step_push(ns, cur, alloc) & once)
							return;

						while (!cur->prev_sibling_c->next_sibling)
						{
							cur = cur->parent;

							if (!cur) return;

							if (!node_is_ancestor(cur, n))
								if (step_push(ns, cur, alloc) & once)
									return;
						}

						cur = cur->prev_sibling_c;
					}
				}

				break;
			}

			case axis_ancestor:
			case axis_ancestor_or_self:
			{
				if (axis == axis_ancestor_or_self)
					if (step_push(ns, n, alloc) & once)
						return;

				xml_node_struct* cur = n->parent;

				while (cur)
				{
					if (step_push(ns, cur, alloc) & once)
						return;

					cur = cur->parent;
				}

				break;
			}

			case axis_self:
			{
				step_push(ns, n, alloc);

				break;
			}

			case axis_parent:
			{
				if (n->parent)
					step_push(ns, n->parent, alloc);

				break;
			}

			default:
				assert(false && "Unimplemented axis"); // unreachable
			}
		}

		template <class T> void step_fill(xpath_node_set_raw& ns, xml_attribute_struct* a, xml_node_struct* p, xpath_allocator* alloc, bool once, T v)
		{
			const axis_t axis = T::axis;

			switch (axis)
			{
			case axis_ancestor:
			case axis_ancestor_or_self:
			{
				if (axis == axis_ancestor_or_self && _test == nodetest_type_node) // reject attributes based on principal node type test
					if (step_push(ns, a, p, alloc) & once)
						return;

				xml_node_struct* cur = p;

				while (cur)
				{
					if (step_push(ns, cur, alloc) & once)
						return;

					cur = cur->parent;
				}

				break;
			}

			case axis_descendant_or_self:
			case axis_self:
			{
				if (_test == nodetest_type_node) // reject attributes based on principal node type test
					step_push(ns, a, p, alloc);

				break;
			}

			case axis_following:
			{
				xml_node_struct* cur = p;

				while (cur)
				{
					if (cur->first_child)
						cur = cur->first_child;
					else
					{
						while (!cur->next_sibling)
						{
							cur = cur->parent;

							if (!cur) return;
						}

						cur = cur->next_sibling;
					}

					if (step_push(ns, cur, alloc) & once)
						return;
				}

				break;
			}

			case axis_parent:
			{
				step_push(ns, p, alloc);

				break;
			}

			case axis_preceding:
			{
				// preceding:: axis does not include attribute nodes and attribute ancestors (they are the same as parent's ancestors), so we can reuse node preceding
				step_fill(ns, p, alloc, once, v);
				break;
			}

			default:
				assert(false && "Unimplemented axis"); // unreachable
			}
		}

		template <class T> void step_fill(xpath_node_set_raw& ns, const xpath_node& xn, xpath_allocator* alloc, bool once, T v)
		{
			const axis_t axis = T::axis;
			const bool axis_has_attributes = (axis == axis_ancestor || axis == axis_ancestor_or_self || axis == axis_descendant_or_self || axis == axis_following || axis == axis_parent || axis == axis_preceding || axis == axis_self);

			if (xn.node())
				step_fill(ns, xn.node().internal_object(), alloc, once, v);
			else if (axis_has_attributes && xn.attribute() && xn.parent())
				step_fill(ns, xn.attribute().internal_object(), xn.parent().internal_object(), alloc, once, v);
		}

		template <class T> xpath_node_set_raw step_do(const xpath_context& c, const xpath_stack& stack, nodeset_eval_t eval, T v)
		{
			const axis_t axis = T::axis;
			const bool axis_reverse = (axis == axis_ancestor || axis == axis_ancestor_or_self || axis == axis_preceding || axis == axis_preceding_sibling);
			const xpath_node_set::type_t axis_type = axis_reverse ? xpath_node_set::type_sorted_reverse : xpath_node_set::type_sorted;

			bool once =
				(axis == axis_attribute && _test == nodetest_name) ||
				(!_right && eval_once(axis_type, eval)) ||
			    // coverity[mixed_enums]
				(_right && !_right->_next && _right->_test == predicate_constant_one);

			xpath_node_set_raw ns;
			ns.set_type(axis_type);

			if (_left)
			{
				xpath_node_set_raw s = _left->eval_node_set(c, stack, nodeset_eval_all);

				// self axis preserves the original order
				if (axis == axis_self) ns.set_type(s.type());

				for (const xpath_node* it = s.begin(); it != s.end(); ++it)
				{
					size_t size = ns.size();

					// in general, all axes generate elements in a particular order, but there is no order guarantee if axis is applied to two nodes
					if (axis != axis_self && size != 0) ns.set_type(xpath_node_set::type_unsorted);

					step_fill(ns, *it, stack.result, once, v);
					if (_right) apply_predicates(ns, size, stack, eval);
				}
			}
			else
			{
				step_fill(ns, c.n, stack.result, once, v);
				if (_right) apply_predicates(ns, 0, stack, eval);
			}

			// child, attribute and self axes always generate unique set of nodes
			// for other axis, if the set stayed sorted, it stayed unique because the traversal algorithms do not visit the same node twice
			if (axis != axis_child && axis != axis_attribute && axis != axis_self && ns.type() == xpath_node_set::type_unsorted)
				ns.remove_duplicates(stack.temp);

			return ns;
		}

	public:
		xpath_ast_node(ast_type_t type, xpath_value_type rettype_, const char_t* value):
			_type(static_cast<char>(type)), _rettype(static_cast<char>(rettype_)), _axis(0), _test(0), _left(0), _right(0), _next(0)
		{
			assert(type == ast_string_constant);
			_data.string = value;
		}

		xpath_ast_node(ast_type_t type, xpath_value_type rettype_, double value):
			_type(static_cast<char>(type)), _rettype(static_cast<char>(rettype_)), _axis(0), _test(0), _left(0), _right(0), _next(0)
		{
			assert(type == ast_number_constant);
			_data.number = value;
		}

		xpath_ast_node(ast_type_t type, xpath_value_type rettype_, xpath_variable* value):
			_type(static_cast<char>(type)), _rettype(static_cast<char>(rettype_)), _axis(0), _test(0), _left(0), _right(0), _next(0)
		{
			assert(type == ast_variable);
			_data.variable = value;
		}

		xpath_ast_node(ast_type_t type, xpath_value_type rettype_, xpath_ast_node* left = 0, xpath_ast_node* right = 0):
			_type(static_cast<char>(type)), _rettype(static_cast<char>(rettype_)), _axis(0), _test(0), _left(left), _right(right), _next(0)
		{
		}

		xpath_ast_node(ast_type_t type, xpath_ast_node* left, axis_t axis, nodetest_t test, const char_t* contents):
			_type(static_cast<char>(type)), _rettype(xpath_type_node_set), _axis(static_cast<char>(axis)), _test(static_cast<char>(test)), _left(left), _right(0), _next(0)
		{
			assert(type == ast_step);
			_data.nodetest = contents;
		}

		xpath_ast_node(ast_type_t type, xpath_ast_node* left, xpath_ast_node* right, predicate_t test):
			_type(static_cast<char>(type)), _rettype(xpath_type_node_set), _axis(0), _test(static_cast<char>(test)), _left(left), _right(right), _next(0)
		{
			assert(type == ast_filter || type == ast_predicate);
		}

		void set_next(xpath_ast_node* value)
		{
			_next = value;
		}

		void set_right(xpath_ast_node* value)
		{
			_right = value;
		}

		bool eval_boolean(const xpath_context& c, const xpath_stack& stack)
		{
			switch (_type)
			{
			case ast_op_or:
				return _left->eval_boolean(c, stack) || _right->eval_boolean(c, stack);

			case ast_op_and:
				return _left->eval_boolean(c, stack) && _right->eval_boolean(c, stack);

			case ast_op_equal:
				return compare_eq(_left, _right, c, stack, equal_to());

			case ast_op_not_equal:
				return compare_eq(_left, _right, c, stack, not_equal_to());

			case ast_op_less:
				return compare_rel(_left, _right, c, stack, less());

			case ast_op_greater:
				return compare_rel(_right, _left, c, stack, less());

			case ast_op_less_or_equal:
				return compare_rel(_left, _right, c, stack, less_equal());

			case ast_op_greater_or_equal:
				return compare_rel(_right, _left, c, stack, less_equal());

			case ast_func_starts_with:
			{
				xpath_allocator_capture cr(stack.result);

				xpath_string lr = _left->eval_string(c, stack);
				xpath_string rr = _right->eval_string(c, stack);

				return starts_with(lr.c_str(), rr.c_str());
			}

			case ast_func_contains:
			{
				xpath_allocator_capture cr(stack.result);

				xpath_string lr = _left->eval_string(c, stack);
				xpath_string rr = _right->eval_string(c, stack);

				return find_substring(lr.c_str(), rr.c_str()) != 0;
			}

			case ast_func_boolean:
				return _left->eval_boolean(c, stack);

			case ast_func_not:
				return !_left->eval_boolean(c, stack);

			case ast_func_true:
				return true;

			case ast_func_false:
				return false;

			case ast_func_lang:
			{
				if (c.n.attribute()) return false;

				xpath_allocator_capture cr(stack.result);

				xpath_string lang = _left->eval_string(c, stack);

				for (xml_node n = c.n.node(); n; n = n.parent())
				{
					xml_attribute a = n.attribute(PUGIXML_TEXT("xml:lang"));

					if (a)
					{
						const char_t* value = a.value();

						// strnicmp / strncasecmp is not portable
						for (const char_t* lit = lang.c_str(); *lit; ++lit)
						{
							if (tolower_ascii(*lit) != tolower_ascii(*value)) return false;
							++value;
						}

						return *value == 0 || *value == '-';
					}
				}

				return false;
			}

			case ast_opt_compare_attribute:
			{
				const char_t* value = (_right->_type == ast_string_constant) ? _right->_data.string : _right->_data.variable->get_string();

				xml_attribute attr = c.n.node().attribute(_left->_data.nodetest);

				return attr && strequal(attr.value(), value) && is_xpath_attribute(attr.name());
			}

			case ast_variable:
			{
				assert(_rettype == _data.variable->type());

				if (_rettype == xpath_type_boolean)
					return _data.variable->get_boolean();

				// variable needs to be converted to the correct type, this is handled by the fallthrough block below
				break;
			}

			default:
				;
			}

			// none of the ast types that return the value directly matched, we need to perform type conversion
			switch (_rettype)
			{
			case xpath_type_number:
				return convert_number_to_boolean(eval_number(c, stack));

			case xpath_type_string:
			{
				xpath_allocator_capture cr(stack.result);

				return !eval_string(c, stack).empty();
			}

			case xpath_type_node_set:
			{
				xpath_allocator_capture cr(stack.result);

				return !eval_node_set(c, stack, nodeset_eval_any).empty();
			}

			default:
				assert(false && "Wrong expression for return type boolean"); // unreachable
				return false;
			}
		}

		double eval_number(const xpath_context& c, const xpath_stack& stack)
		{
			switch (_type)
			{
			case ast_op_add:
				return _left->eval_number(c, stack) + _right->eval_number(c, stack);

			case ast_op_subtract:
				return _left->eval_number(c, stack) - _right->eval_number(c, stack);

			case ast_op_multiply:
				return _left->eval_number(c, stack) * _right->eval_number(c, stack);

			case ast_op_divide:
				return _left->eval_number(c, stack) / _right->eval_number(c, stack);

			case ast_op_mod:
				return fmod(_left->eval_number(c, stack), _right->eval_number(c, stack));

			case ast_op_negate:
				return -_left->eval_number(c, stack);

			case ast_number_constant:
				return _data.number;

			case ast_func_last:
				return static_cast<double>(c.size);

			case ast_func_position:
				return static_cast<double>(c.position);

			case ast_func_count:
			{
				xpath_allocator_capture cr(stack.result);

				return static_cast<double>(_left->eval_node_set(c, stack, nodeset_eval_all).size());
			}

			case ast_func_string_length_0:
			{
				xpath_allocator_capture cr(stack.result);

				return static_cast<double>(string_value(c.n, stack.result).length());
			}

			case ast_func_string_length_1:
			{
				xpath_allocator_capture cr(stack.result);

				return static_cast<double>(_left->eval_string(c, stack).length());
			}

			case ast_func_number_0:
			{
				xpath_allocator_capture cr(stack.result);

				return convert_string_to_number(string_value(c.n, stack.result).c_str());
			}

			case ast_func_number_1:
				return _left->eval_number(c, stack);

			case ast_func_sum:
			{
				xpath_allocator_capture cr(stack.result);

				double r = 0;

				xpath_node_set_raw ns = _left->eval_node_set(c, stack, nodeset_eval_all);

				for (const xpath_node* it = ns.begin(); it != ns.end(); ++it)
				{
					xpath_allocator_capture cri(stack.result);

					r += convert_string_to_number(string_value(*it, stack.result).c_str());
				}

				return r;
			}

			case ast_func_floor:
			{
				double r = _left->eval_number(c, stack);

				return r == r ? floor(r) : r;
			}

			case ast_func_ceiling:
			{
				double r = _left->eval_number(c, stack);

				return r == r ? ceil(r) : r;
			}

			case ast_func_round:
				return round_nearest_nzero(_left->eval_number(c, stack));

			case ast_variable:
			{
				assert(_rettype == _data.variable->type());

				if (_rettype == xpath_type_number)
					return _data.variable->get_number();

				// variable needs to be converted to the correct type, this is handled by the fallthrough block below
				break;
			}

			default:
				;
			}

			// none of the ast types that return the value directly matched, we need to perform type conversion
			switch (_rettype)
			{
			case xpath_type_boolean:
				return eval_boolean(c, stack) ? 1 : 0;

			case xpath_type_string:
			{
				xpath_allocator_capture cr(stack.result);

				return convert_string_to_number(eval_string(c, stack).c_str());
			}

			case xpath_type_node_set:
			{
				xpath_allocator_capture cr(stack.result);

				return convert_string_to_number(eval_string(c, stack).c_str());
			}

			default:
				assert(false && "Wrong expression for return type number"); // unreachable
				return 0;
			}
		}

		xpath_string eval_string_concat(const xpath_context& c, const xpath_stack& stack)
		{
			assert(_type == ast_func_concat);

			xpath_allocator_capture ct(stack.temp);

			// count the string number
			size_t count = 1;
			for (xpath_ast_node* nc = _right; nc; nc = nc->_next) count++;

			// allocate a buffer for temporary string objects
			xpath_string* buffer = static_cast<xpath_string*>(stack.temp->allocate(count * sizeof(xpath_string)));
			if (!buffer) return xpath_string();

			// evaluate all strings to temporary stack
			xpath_stack swapped_stack = {stack.temp, stack.result};

			buffer[0] = _left->eval_string(c, swapped_stack);

			size_t pos = 1;
			for (xpath_ast_node* n = _right; n; n = n->_next, ++pos) buffer[pos] = n->eval_string(c, swapped_stack);
			assert(pos == count);

			// get total length
			size_t length = 0;
			for (size_t i = 0; i < count; ++i) length += buffer[i].length();

			// create final string
			char_t* result = static_cast<char_t*>(stack.result->allocate((length + 1) * sizeof(char_t)));
			if (!result) return xpath_string();

			char_t* ri = result;

			for (size_t j = 0; j < count; ++j)
				for (const char_t* bi = buffer[j].c_str(); *bi; ++bi)
					*ri++ = *bi;

			*ri = 0;

			return xpath_string::from_heap_preallocated(result, ri);
		}

		xpath_string eval_string(const xpath_context& c, const xpath_stack& stack)
		{
			switch (_type)
			{
			case ast_string_constant:
				return xpath_string::from_const(_data.string);

			case ast_func_local_name_0:
			{
				xpath_node na = c.n;

				return xpath_string::from_const(local_name(na));
			}

			case ast_func_local_name_1:
			{
				xpath_allocator_capture cr(stack.result);

				xpath_node_set_raw ns = _left->eval_node_set(c, stack, nodeset_eval_first);
				xpath_node na = ns.first();

				return xpath_string::from_const(local_name(na));
			}

			case ast_func_name_0:
			{
				xpath_node na = c.n;

				return xpath_string::from_const(qualified_name(na));
			}

			case ast_func_name_1:
			{
				xpath_allocator_capture cr(stack.result);

				xpath_node_set_raw ns = _left->eval_node_set(c, stack, nodeset_eval_first);
				xpath_node na = ns.first();

				return xpath_string::from_const(qualified_name(na));
			}

			case ast_func_namespace_uri_0:
			{
				xpath_node na = c.n;

				return xpath_string::from_const(namespace_uri(na));
			}

			case ast_func_namespace_uri_1:
			{
				xpath_allocator_capture cr(stack.result);

				xpath_node_set_raw ns = _left->eval_node_set(c, stack, nodeset_eval_first);
				xpath_node na = ns.first();

				return xpath_string::from_const(namespace_uri(na));
			}

			case ast_func_string_0:
				return string_value(c.n, stack.result);

			case ast_func_string_1:
				return _left->eval_string(c, stack);

			case ast_func_concat:
				return eval_string_concat(c, stack);

			case ast_func_substring_before:
			{
				xpath_allocator_capture cr(stack.temp);

				xpath_stack swapped_stack = {stack.temp, stack.result};

				xpath_string s = _left->eval_string(c, swapped_stack);
				xpath_string p = _right->eval_string(c, swapped_stack);

				const char_t* pos = find_substring(s.c_str(), p.c_str());

				return pos ? xpath_string::from_heap(s.c_str(), pos, stack.result) : xpath_string();
			}

			case ast_func_substring_after:
			{
				xpath_allocator_capture cr(stack.temp);

				xpath_stack swapped_stack = {stack.temp, stack.result};

				xpath_string s = _left->eval_string(c, swapped_stack);
				xpath_string p = _right->eval_string(c, swapped_stack);

				const char_t* pos = find_substring(s.c_str(), p.c_str());
				if (!pos) return xpath_string();

				const char_t* rbegin = pos + p.length();
				const char_t* rend = s.c_str() + s.length();

				return s.uses_heap() ? xpath_string::from_heap(rbegin, rend, stack.result) : xpath_string::from_const(rbegin);
			}

			case ast_func_substring_2:
			{
				xpath_allocator_capture cr(stack.temp);

				xpath_stack swapped_stack = {stack.temp, stack.result};

				xpath_string s = _left->eval_string(c, swapped_stack);
				size_t s_length = s.length();

				double first = round_nearest(_right->eval_number(c, stack));

				if (is_nan(first)) return xpath_string(); // NaN
				else if (first >= static_cast<double>(s_length + 1)) return xpath_string();

				size_t pos = first < 1 ? 1 : static_cast<size_t>(first);
				assert(1 <= pos && pos <= s_length + 1);

				const char_t* rbegin = s.c_str() + (pos - 1);
				const char_t* rend = s.c_str() + s.length();

				return s.uses_heap() ? xpath_string::from_heap(rbegin, rend, stack.result) : xpath_string::from_const(rbegin);
			}

			case ast_func_substring_3:
			{
				xpath_allocator_capture cr(stack.temp);

				xpath_stack swapped_stack = {stack.temp, stack.result};

				xpath_string s = _left->eval_string(c, swapped_stack);
				size_t s_length = s.length();

				double first = round_nearest(_right->eval_number(c, stack));
				double last = first + round_nearest(_right->_next->eval_number(c, stack));

				if (is_nan(first) || is_nan(last)) return xpath_string();
				else if (first >= static_cast<double>(s_length + 1)) return xpath_string();
				else if (first >= last) return xpath_string();
				else if (last < 1) return xpath_string();

				size_t pos = first < 1 ? 1 : static_cast<size_t>(first);
				size_t end = last >= static_cast<double>(s_length + 1) ? s_length + 1 : static_cast<size_t>(last);

				assert(1 <= pos && pos <= end && end <= s_length + 1);
				const char_t* rbegin = s.c_str() + (pos - 1);
				const char_t* rend = s.c_str() + (end - 1);

				return (end == s_length + 1 && !s.uses_heap()) ? xpath_string::from_const(rbegin) : xpath_string::from_heap(rbegin, rend, stack.result);
			}

			case ast_func_normalize_space_0:
			{
				xpath_string s = string_value(c.n, stack.result);

				char_t* begin = s.data(stack.result);
				if (!begin) return xpath_string();

				char_t* end = normalize_space(begin);

				return xpath_string::from_heap_preallocated(begin, end);
			}

			case ast_func_normalize_space_1:
			{
				xpath_string s = _left->eval_string(c, stack);

				char_t* begin = s.data(stack.result);
				if (!begin) return xpath_string();

				char_t* end = normalize_space(begin);

				return xpath_string::from_heap_preallocated(begin, end);
			}

			case ast_func_translate:
			{
				xpath_allocator_capture cr(stack.temp);

				xpath_stack swapped_stack = {stack.temp, stack.result};

				xpath_string s = _left->eval_string(c, stack);
				xpath_string from = _right->eval_string(c, swapped_stack);
				xpath_string to = _right->_next->eval_string(c, swapped_stack);

				char_t* begin = s.data(stack.result);
				if (!begin) return xpath_string();

				char_t* end = translate(begin, from.c_str(), to.c_str(), to.length());

				return xpath_string::from_heap_preallocated(begin, end);
			}

			case ast_opt_translate_table:
			{
				xpath_string s = _left->eval_string(c, stack);

				char_t* begin = s.data(stack.result);
				if (!begin) return xpath_string();

				char_t* end = translate_table(begin, _data.table);

				return xpath_string::from_heap_preallocated(begin, end);
			}

			case ast_variable:
			{
				assert(_rettype == _data.variable->type());

				if (_rettype == xpath_type_string)
					return xpath_string::from_const(_data.variable->get_string());

				// variable needs to be converted to the correct type, this is handled by the fallthrough block below
				break;
			}

			default:
				;
			}

			// none of the ast types that return the value directly matched, we need to perform type conversion
			switch (_rettype)
			{
			case xpath_type_boolean:
				return xpath_string::from_const(eval_boolean(c, stack) ? PUGIXML_TEXT("true") : PUGIXML_TEXT("false"));

			case xpath_type_number:
				return convert_number_to_string(eval_number(c, stack), stack.result);

			case xpath_type_node_set:
			{
				xpath_allocator_capture cr(stack.temp);

				xpath_stack swapped_stack = {stack.temp, stack.result};

				xpath_node_set_raw ns = eval_node_set(c, swapped_stack, nodeset_eval_first);
				return ns.empty() ? xpath_string() : string_value(ns.first(), stack.result);
			}

			default:
				assert(false && "Wrong expression for return type string"); // unreachable
				return xpath_string();
			}
		}

		xpath_node_set_raw eval_node_set(const xpath_context& c, const xpath_stack& stack, nodeset_eval_t eval)
		{
			switch (_type)
			{
			case ast_op_union:
			{
				xpath_allocator_capture cr(stack.temp);

				xpath_stack swapped_stack = {stack.temp, stack.result};

				xpath_node_set_raw ls = _left->eval_node_set(c, stack, eval);
				xpath_node_set_raw rs = _right->eval_node_set(c, swapped_stack, eval);

				// we can optimize merging two sorted sets, but this is a very rare operation, so don't bother
				ls.set_type(xpath_node_set::type_unsorted);

				ls.append(rs.begin(), rs.end(), stack.result);
				ls.remove_duplicates(stack.temp);

				return ls;
			}

			case ast_filter:
			{
				xpath_node_set_raw set = _left->eval_node_set(c, stack, _test == predicate_constant_one ? nodeset_eval_first : nodeset_eval_all);

				// either expression is a number or it contains position() call; sort by document order
				if (_test != predicate_posinv) set.sort_do();

				bool once = eval_once(set.type(), eval);

				apply_predicate(set, 0, stack, once);

				return set;
			}

			case ast_func_id:
				return xpath_node_set_raw();

			case ast_step:
			{
				switch (_axis)
				{
				case axis_ancestor:
					return step_do(c, stack, eval, axis_to_type<axis_ancestor>());

				case axis_ancestor_or_self:
					return step_do(c, stack, eval, axis_to_type<axis_ancestor_or_self>());

				case axis_attribute:
					return step_do(c, stack, eval, axis_to_type<axis_attribute>());

				case axis_child:
					return step_do(c, stack, eval, axis_to_type<axis_child>());

				case axis_descendant:
					return step_do(c, stack, eval, axis_to_type<axis_descendant>());

				case axis_descendant_or_self:
					return step_do(c, stack, eval, axis_to_type<axis_descendant_or_self>());

				case axis_following:
					return step_do(c, stack, eval, axis_to_type<axis_following>());

				case axis_following_sibling:
					return step_do(c, stack, eval, axis_to_type<axis_following_sibling>());

				case axis_namespace:
					// namespaced axis is not supported
					return xpath_node_set_raw();

				case axis_parent:
					return step_do(c, stack, eval, axis_to_type<axis_parent>());

				case axis_preceding:
					return step_do(c, stack, eval, axis_to_type<axis_preceding>());

				case axis_preceding_sibling:
					return step_do(c, stack, eval, axis_to_type<axis_preceding_sibling>());

				case axis_self:
					return step_do(c, stack, eval, axis_to_type<axis_self>());

				default:
					assert(false && "Unknown axis"); // unreachable
					return xpath_node_set_raw();
				}
			}

			case ast_step_root:
			{
				assert(!_right); // root step can't have any predicates

				xpath_node_set_raw ns;

				ns.set_type(xpath_node_set::type_sorted);

				if (c.n.node()) ns.push_back(c.n.node().root(), stack.result);
				else if (c.n.attribute()) ns.push_back(c.n.parent().root(), stack.result);

				return ns;
			}

			case ast_variable:
			{
				assert(_rettype == _data.variable->type());

				if (_rettype == xpath_type_node_set)
				{
					const xpath_node_set& s = _data.variable->get_node_set();

					xpath_node_set_raw ns;

					ns.set_type(s.type());
					ns.append(s.begin(), s.end(), stack.result);

					return ns;
				}

				// variable needs to be converted to the correct type, this is handled by the fallthrough block below
				break;
			}

			default:
				;
			}

			// none of the ast types that return the value directly matched, but conversions to node set are invalid
			assert(false && "Wrong expression for return type node set"); // unreachable
			return xpath_node_set_raw();
		}

		void optimize(xpath_allocator* alloc)
		{
			if (_left)
				_left->optimize(alloc);

			if (_right)
				_right->optimize(alloc);

			if (_next)
				_next->optimize(alloc);

			// coverity[var_deref_model]
			optimize_self(alloc);
		}

		void optimize_self(xpath_allocator* alloc)
		{
			// Rewrite [position()=expr] with [expr]
			// Note that this step has to go before classification to recognize [position()=1]
			if ((_type == ast_filter || _type == ast_predicate) &&
				_right && // workaround for clang static analyzer (_right is never null for ast_filter/ast_predicate)
				_right->_type == ast_op_equal && _right->_left->_type == ast_func_position && _right->_right->_rettype == xpath_type_number)
			{
				_right = _right->_right;
			}

			// Classify filter/predicate ops to perform various optimizations during evaluation
			if ((_type == ast_filter || _type == ast_predicate) && _right) // workaround for clang static analyzer (_right is never null for ast_filter/ast_predicate)
			{
				assert(_test == predicate_default);

				if (_right->_type == ast_number_constant && _right->_data.number == 1.0)
					_test = predicate_constant_one;
				else if (_right->_rettype == xpath_type_number && (_right->_type == ast_number_constant || _right->_type == ast_variable || _right->_type == ast_func_last))
					_test = predicate_constant;
				else if (_right->_rettype != xpath_type_number && _right->is_posinv_expr())
					_test = predicate_posinv;
			}

			// Rewrite descendant-or-self::node()/child::foo with descendant::foo
			// The former is a full form of //foo, the latter is much faster since it executes the node test immediately
			// Do a similar kind of rewrite for self/descendant/descendant-or-self axes
			// Note that we only rewrite positionally invariant steps (//foo[1] != /descendant::foo[1])
			if (_type == ast_step && (_axis == axis_child || _axis == axis_self || _axis == axis_descendant || _axis == axis_descendant_or_self) &&
				_left && _left->_type == ast_step && _left->_axis == axis_descendant_or_self && _left->_test == nodetest_type_node && !_left->_right &&
				is_posinv_step())
			{
				if (_axis == axis_child || _axis == axis_descendant)
					_axis = axis_descendant;
				else
					_axis = axis_descendant_or_self;

				_left = _left->_left;
			}

			// Use optimized lookup table implementation for translate() with constant arguments
			if (_type == ast_func_translate &&
				_right && // workaround for clang static analyzer (_right is never null for ast_func_translate)
				_right->_type == ast_string_constant && _right->_next->_type == ast_string_constant)
			{
				unsigned char* table = translate_table_generate(alloc, _right->_data.string, _right->_next->_data.string);

				if (table)
				{
					_type = ast_opt_translate_table;
					_data.table = table;
				}
			}

			// Use optimized path for @attr = 'value' or @attr = $value
			if (_type == ast_op_equal &&
				_left && _right && // workaround for clang static analyzer and Coverity (_left and _right are never null for ast_op_equal)
                // coverity[mixed_enums]
				_left->_type == ast_step && _left->_axis == axis_attribute && _left->_test == nodetest_name && !_left->_left && !_left->_right &&
				(_right->_type == ast_string_constant || (_right->_type == ast_variable && _right->_rettype == xpath_type_string)))
			{
				_type = ast_opt_compare_attribute;
			}
		}

		bool is_posinv_expr() const
		{
			switch (_type)
			{
			case ast_func_position:
			case ast_func_last:
				return false;

			case ast_string_constant:
			case ast_number_constant:
			case ast_variable:
				return true;

			case ast_step:
			case ast_step_root:
				return true;

			case ast_predicate:
			case ast_filter:
				return true;

			default:
				if (_left && !_left->is_posinv_expr()) return false;

				for (xpath_ast_node* n = _right; n; n = n->_next)
					if (!n->is_posinv_expr()) return false;

				return true;
			}
		}

		bool is_posinv_step() const
		{
			assert(_type == ast_step);

			for (xpath_ast_node* n = _right; n; n = n->_next)
			{
				assert(n->_type == ast_predicate);

				if (n->_test != predicate_posinv)
					return false;
			}

			return true;
		}

		xpath_value_type rettype() const
		{
			return static_cast<xpath_value_type>(_rettype);
		}
	};

	static const size_t xpath_ast_depth_limit =
	#ifdef PUGIXML_XPATH_DEPTH_LIMIT
		PUGIXML_XPATH_DEPTH_LIMIT
	#else
		1024
	#endif
		;

	struct xpath_parser
	{
		xpath_allocator* _alloc;
		xpath_lexer _lexer;

		const char_t* _query;
		xpath_variable_set* _variables;

		xpath_parse_result* _result;

		char_t _scratch[32];

		size_t _depth;

		xpath_ast_node* error(const char* message)
		{
			_result->error = message;
			_result->offset = _lexer.current_pos() - _query;

			return 0;
		}

		xpath_ast_node* error_oom()
		{
			assert(_alloc->_error);
			*_alloc->_error = true;

			return 0;
		}

		xpath_ast_node* error_rec()
		{
			return error("Exceeded maximum allowed query depth");
		}

		void* alloc_node()
		{
			return _alloc->allocate(sizeof(xpath_ast_node));
		}

		xpath_ast_node* alloc_node(ast_type_t type, xpath_value_type rettype, const char_t* value)
		{
			void* memory = alloc_node();
			return memory ? new (memory) xpath_ast_node(type, rettype, value) : 0;
		}

		xpath_ast_node* alloc_node(ast_type_t type, xpath_value_type rettype, double value)
		{
			void* memory = alloc_node();
			return memory ? new (memory) xpath_ast_node(type, rettype, value) : 0;
		}

		xpath_ast_node* alloc_node(ast_type_t type, xpath_value_type rettype, xpath_variable* value)
		{
			void* memory = alloc_node();
			return memory ? new (memory) xpath_ast_node(type, rettype, value) : 0;
		}

		xpath_ast_node* alloc_node(ast_type_t type, xpath_value_type rettype, xpath_ast_node* left = 0, xpath_ast_node* right = 0)
		{
			void* memory = alloc_node();
			return memory ? new (memory) xpath_ast_node(type, rettype, left, right) : 0;
		}

		xpath_ast_node* alloc_node(ast_type_t type, xpath_ast_node* left, axis_t axis, nodetest_t test, const char_t* contents)
		{
			void* memory = alloc_node();
			return memory ? new (memory) xpath_ast_node(type, left, axis, test, contents) : 0;
		}

		xpath_ast_node* alloc_node(ast_type_t type, xpath_ast_node* left, xpath_ast_node* right, predicate_t test)
		{
			void* memory = alloc_node();
			return memory ? new (memory) xpath_ast_node(type, left, right, test) : 0;
		}

		const char_t* alloc_string(const xpath_lexer_string& value)
		{
			if (!value.begin)
				return PUGIXML_TEXT("");

			size_t length = static_cast<size_t>(value.end - value.begin);

			char_t* c = static_cast<char_t*>(_alloc->allocate((length + 1) * sizeof(char_t)));
			if (!c) return 0;

			memcpy(c, value.begin, length * sizeof(char_t));
			c[length] = 0;

			return c;
		}

		xpath_ast_node* parse_function(const xpath_lexer_string& name, size_t argc, xpath_ast_node* args[2])
		{
			switch (name.begin[0])
			{
			case 'b':
				if (name == PUGIXML_TEXT("boolean") && argc == 1)
					return alloc_node(ast_func_boolean, xpath_type_boolean, args[0]);

				break;

			case 'c':
				if (name == PUGIXML_TEXT("count") && argc == 1)
				{
					if (args[0]->rettype() != xpath_type_node_set) return error("Function has to be applied to node set");
					return alloc_node(ast_func_count, xpath_type_number, args[0]);
				}
				else if (name == PUGIXML_TEXT("contains") && argc == 2)
					return alloc_node(ast_func_contains, xpath_type_boolean, args[0], args[1]);
				else if (name == PUGIXML_TEXT("concat") && argc >= 2)
					return alloc_node(ast_func_concat, xpath_type_string, args[0], args[1]);
				else if (name == PUGIXML_TEXT("ceiling") && argc == 1)
					return alloc_node(ast_func_ceiling, xpath_type_number, args[0]);

				break;

			case 'f':
				if (name == PUGIXML_TEXT("false") && argc == 0)
					return alloc_node(ast_func_false, xpath_type_boolean);
				else if (name == PUGIXML_TEXT("floor") && argc == 1)
					return alloc_node(ast_func_floor, xpath_type_number, args[0]);

				break;

			case 'i':
				if (name == PUGIXML_TEXT("id") && argc == 1)
					return alloc_node(ast_func_id, xpath_type_node_set, args[0]);

				break;

			case 'l':
				if (name == PUGIXML_TEXT("last") && argc == 0)
					return alloc_node(ast_func_last, xpath_type_number);
				else if (name == PUGIXML_TEXT("lang") && argc == 1)
					return alloc_node(ast_func_lang, xpath_type_boolean, args[0]);
				else if (name == PUGIXML_TEXT("local-name") && argc <= 1)
				{
					if (argc == 1 && args[0]->rettype() != xpath_type_node_set) return error("Function has to be applied to node set");
					return alloc_node(argc == 0 ? ast_func_local_name_0 : ast_func_local_name_1, xpath_type_string, args[0]);
				}

				break;

			case 'n':
				if (name == PUGIXML_TEXT("name") && argc <= 1)
				{
					if (argc == 1 && args[0]->rettype() != xpath_type_node_set) return error("Function has to be applied to node set");
					return alloc_node(argc == 0 ? ast_func_name_0 : ast_func_name_1, xpath_type_string, args[0]);
				}
				else if (name == PUGIXML_TEXT("namespace-uri") && argc <= 1)
				{
					if (argc == 1 && args[0]->rettype() != xpath_type_node_set) return error("Function has to be applied to node set");
					return alloc_node(argc == 0 ? ast_func_namespace_uri_0 : ast_func_namespace_uri_1, xpath_type_string, args[0]);
				}
				else if (name == PUGIXML_TEXT("normalize-space") && argc <= 1)
					return alloc_node(argc == 0 ? ast_func_normalize_space_0 : ast_func_normalize_space_1, xpath_type_string, args[0], args[1]);
				else if (name == PUGIXML_TEXT("not") && argc == 1)
					return alloc_node(ast_func_not, xpath_type_boolean, args[0]);
				else if (name == PUGIXML_TEXT("number") && argc <= 1)
					return alloc_node(argc == 0 ? ast_func_number_0 : ast_func_number_1, xpath_type_number, args[0]);

				break;

			case 'p':
				if (name == PUGIXML_TEXT("position") && argc == 0)
					return alloc_node(ast_func_position, xpath_type_number);

				break;

			case 'r':
				if (name == PUGIXML_TEXT("round") && argc == 1)
					return alloc_node(ast_func_round, xpath_type_number, args[0]);

				break;

			case 's':
				if (name == PUGIXML_TEXT("string") && argc <= 1)
					return alloc_node(argc == 0 ? ast_func_string_0 : ast_func_string_1, xpath_type_string, args[0]);
				else if (name == PUGIXML_TEXT("string-length") && argc <= 1)
					return alloc_node(argc == 0 ? ast_func_string_length_0 : ast_func_string_length_1, xpath_type_number, args[0]);
				else if (name == PUGIXML_TEXT("starts-with") && argc == 2)
					return alloc_node(ast_func_starts_with, xpath_type_boolean, args[0], args[1]);
				else if (name == PUGIXML_TEXT("substring-before") && argc == 2)
					return alloc_node(ast_func_substring_before, xpath_type_string, args[0], args[1]);
				else if (name == PUGIXML_TEXT("substring-after") && argc == 2)
					return alloc_node(ast_func_substring_after, xpath_type_string, args[0], args[1]);
				else if (name == PUGIXML_TEXT("substring") && (argc == 2 || argc == 3))
					return alloc_node(argc == 2 ? ast_func_substring_2 : ast_func_substring_3, xpath_type_string, args[0], args[1]);
				else if (name == PUGIXML_TEXT("sum") && argc == 1)
				{
					if (args[0]->rettype() != xpath_type_node_set) return error("Function has to be applied to node set");
					return alloc_node(ast_func_sum, xpath_type_number, args[0]);
				}

				break;

			case 't':
				if (name == PUGIXML_TEXT("translate") && argc == 3)
					return alloc_node(ast_func_translate, xpath_type_string, args[0], args[1]);
				else if (name == PUGIXML_TEXT("true") && argc == 0)
					return alloc_node(ast_func_true, xpath_type_boolean);

				break;

			default:
				break;
			}

			return error("Unrecognized function or wrong parameter count");
		}

		axis_t parse_axis_name(const xpath_lexer_string& name, bool& specified)
		{
			specified = true;

			switch (name.begin[0])
			{
			case 'a':
				if (name == PUGIXML_TEXT("ancestor"))
					return axis_ancestor;
				else if (name == PUGIXML_TEXT("ancestor-or-self"))
					return axis_ancestor_or_self;
				else if (name == PUGIXML_TEXT("attribute"))
					return axis_attribute;

				break;

			case 'c':
				if (name == PUGIXML_TEXT("child"))
					return axis_child;

				break;

			case 'd':
				if (name == PUGIXML_TEXT("descendant"))
					return axis_descendant;
				else if (name == PUGIXML_TEXT("descendant-or-self"))
					return axis_descendant_or_self;

				break;

			case 'f':
				if (name == PUGIXML_TEXT("following"))
					return axis_following;
				else if (name == PUGIXML_TEXT("following-sibling"))
					return axis_following_sibling;

				break;

			case 'n':
				if (name == PUGIXML_TEXT("namespace"))
					return axis_namespace;

				break;

			case 'p':
				if (name == PUGIXML_TEXT("parent"))
					return axis_parent;
				else if (name == PUGIXML_TEXT("preceding"))
					return axis_preceding;
				else if (name == PUGIXML_TEXT("preceding-sibling"))
					return axis_preceding_sibling;

				break;

			case 's':
				if (name == PUGIXML_TEXT("self"))
					return axis_self;

				break;

			default:
				break;
			}

			specified = false;
			return axis_child;
		}

		nodetest_t parse_node_test_type(const xpath_lexer_string& name)
		{
			switch (name.begin[0])
			{
			case 'c':
				if (name == PUGIXML_TEXT("comment"))
					return nodetest_type_comment;

				break;

			case 'n':
				if (name == PUGIXML_TEXT("node"))
					return nodetest_type_node;

				break;

			case 'p':
				if (name == PUGIXML_TEXT("processing-instruction"))
					return nodetest_type_pi;

				break;

			case 't':
				if (name == PUGIXML_TEXT("text"))
					return nodetest_type_text;

				break;

			default:
				break;
			}

			return nodetest_none;
		}

		// PrimaryExpr ::= VariableReference | '(' Expr ')' | Literal | Number | FunctionCall
		xpath_ast_node* parse_primary_expression()
		{
			switch (_lexer.current())
			{
			case lex_var_ref:
			{
				xpath_lexer_string name = _lexer.contents();

				if (!_variables)
					return error("Unknown variable: variable set is not provided");

				xpath_variable* var = 0;
				if (!get_variable_scratch(_scratch, _variables, name.begin, name.end, &var))
					return error_oom();

				if (!var)
					return error("Unknown variable: variable set does not contain the given name");

				_lexer.next();

				return alloc_node(ast_variable, var->type(), var);
			}

			case lex_open_brace:
			{
				_lexer.next();

				xpath_ast_node* n = parse_expression();
				if (!n) return 0;

				if (_lexer.current() != lex_close_brace)
					return error("Expected ')' to match an opening '('");

				_lexer.next();

				return n;
			}

			case lex_quoted_string:
			{
				const char_t* value = alloc_string(_lexer.contents());
				if (!value) return 0;

				_lexer.next();

				return alloc_node(ast_string_constant, xpath_type_string, value);
			}

			case lex_number:
			{
				double value = 0;

				if (!convert_string_to_number_scratch(_scratch, _lexer.contents().begin, _lexer.contents().end, &value))
					return error_oom();

				_lexer.next();

				return alloc_node(ast_number_constant, xpath_type_number, value);
			}

			case lex_string:
			{
				xpath_ast_node* args[2] = {0};
				size_t argc = 0;

				xpath_lexer_string function = _lexer.contents();
				_lexer.next();

				xpath_ast_node* last_arg = 0;

				if (_lexer.current() != lex_open_brace)
					return error("Unrecognized function call");
				_lexer.next();

				size_t old_depth = _depth;

				while (_lexer.current() != lex_close_brace)
				{
					if (argc > 0)
					{
						if (_lexer.current() != lex_comma)
							return error("No comma between function arguments");
						_lexer.next();
					}

					if (++_depth > xpath_ast_depth_limit)
						return error_rec();

					xpath_ast_node* n = parse_expression();
					if (!n) return 0;

					if (argc < 2) args[argc] = n;
					else last_arg->set_next(n);

					argc++;
					last_arg = n;
				}

				_lexer.next();

				_depth = old_depth;

				return parse_function(function, argc, args);
			}

			default:
				return error("Unrecognizable primary expression");
			}
		}

		// FilterExpr ::= PrimaryExpr | FilterExpr Predicate
		// Predicate ::= '[' PredicateExpr ']'
		// PredicateExpr ::= Expr
		xpath_ast_node* parse_filter_expression()
		{
			xpath_ast_node* n = parse_primary_expression();
			if (!n) return 0;

			size_t old_depth = _depth;

			while (_lexer.current() == lex_open_square_brace)
			{
				_lexer.next();

				if (++_depth > xpath_ast_depth_limit)
					return error_rec();

				if (n->rettype() != xpath_type_node_set)
					return error("Predicate has to be applied to node set");

				xpath_ast_node* expr = parse_expression();
				if (!expr) return 0;

				n = alloc_node(ast_filter, n, expr, predicate_default);
				if (!n) return 0;

				if (_lexer.current() != lex_close_square_brace)
					return error("Expected ']' to match an opening '['");

				_lexer.next();
			}

			_depth = old_depth;

			return n;
		}

		// Step ::= AxisSpecifier NodeTest Predicate* | AbbreviatedStep
		// AxisSpecifier ::= AxisName '::' | '@'?
		// NodeTest ::= NameTest | NodeType '(' ')' | 'processing-instruction' '(' Literal ')'
		// NameTest ::= '*' | NCName ':' '*' | QName
		// AbbreviatedStep ::= '.' | '..'
		xpath_ast_node* parse_step(xpath_ast_node* set)
		{
			if (set && set->rettype() != xpath_type_node_set)
				return error("Step has to be applied to node set");

			bool axis_specified = false;
			axis_t axis = axis_child; // implied child axis

			if (_lexer.current() == lex_axis_attribute)
			{
				axis = axis_attribute;
				axis_specified = true;

				_lexer.next();
			}
			else if (_lexer.current() == lex_dot)
			{
				_lexer.next();

				if (_lexer.current() == lex_open_square_brace)
					return error("Predicates are not allowed after an abbreviated step");

				return alloc_node(ast_step, set, axis_self, nodetest_type_node, 0);
			}
			else if (_lexer.current() == lex_double_dot)
			{
				_lexer.next();

				if (_lexer.current() == lex_open_square_brace)
					return error("Predicates are not allowed after an abbreviated step");

				return alloc_node(ast_step, set, axis_parent, nodetest_type_node, 0);
			}

			nodetest_t nt_type = nodetest_none;
			xpath_lexer_string nt_name;

			if (_lexer.current() == lex_string)
			{
				// node name test
				nt_name = _lexer.contents();
				_lexer.next();

				// was it an axis name?
				if (_lexer.current() == lex_double_colon)
				{
					// parse axis name
					if (axis_specified)
						return error("Two axis specifiers in one step");

					axis = parse_axis_name(nt_name, axis_specified);

					if (!axis_specified)
						return error("Unknown axis");

					// read actual node test
					_lexer.next();

					if (_lexer.current() == lex_multiply)
					{
						nt_type = nodetest_all;
						nt_name = xpath_lexer_string();
						_lexer.next();
					}
					else if (_lexer.current() == lex_string)
					{
						nt_name = _lexer.contents();
						_lexer.next();
					}
					else
					{
						return error("Unrecognized node test");
					}
				}

				if (nt_type == nodetest_none)
				{
					// node type test or processing-instruction
					if (_lexer.current() == lex_open_brace)
					{
						_lexer.next();

						if (_lexer.current() == lex_close_brace)
						{
							_lexer.next();

							nt_type = parse_node_test_type(nt_name);

							if (nt_type == nodetest_none)
								return error("Unrecognized node type");

							nt_name = xpath_lexer_string();
						}
						else if (nt_name == PUGIXML_TEXT("processing-instruction"))
						{
							if (_lexer.current() != lex_quoted_string)
								return error("Only literals are allowed as arguments to processing-instruction()");

							nt_type = nodetest_pi;
							nt_name = _lexer.contents();
							_lexer.next();

							if (_lexer.current() != lex_close_brace)
								return error("Unmatched brace near processing-instruction()");
							_lexer.next();
						}
						else
						{
							return error("Unmatched brace near node type test");
						}
					}
					// QName or NCName:*
					else
					{
						if (nt_name.end - nt_name.begin > 2 && nt_name.end[-2] == ':' && nt_name.end[-1] == '*') // NCName:*
						{
							nt_name.end--; // erase *

							nt_type = nodetest_all_in_namespace;
						}
						else
						{
							nt_type = nodetest_name;
						}
					}
				}
			}
			else if (_lexer.current() == lex_multiply)
			{
				nt_type = nodetest_all;
				_lexer.next();
			}
			else
			{
				return error("Unrecognized node test");
			}

			const char_t* nt_name_copy = alloc_string(nt_name);
			if (!nt_name_copy) return 0;

			xpath_ast_node* n = alloc_node(ast_step, set, axis, nt_type, nt_name_copy);
			if (!n) return 0;

			size_t old_depth = _depth;

			xpath_ast_node* last = 0;

			while (_lexer.current() == lex_open_square_brace)
			{
				_lexer.next();

				if (++_depth > xpath_ast_depth_limit)
					return error_rec();

				xpath_ast_node* expr = parse_expression();
				if (!expr) return 0;

				xpath_ast_node* pred = alloc_node(ast_predicate, 0, expr, predicate_default);
				if (!pred) return 0;

				if (_lexer.current() != lex_close_square_brace)
					return error("Expected ']' to match an opening '['");
				_lexer.next();

				if (last) last->set_next(pred);
				else n->set_right(pred);

				last = pred;
			}

			_depth = old_depth;

			return n;
		}

		// RelativeLocationPath ::= Step | RelativeLocationPath '/' Step | RelativeLocationPath '//' Step
		xpath_ast_node* parse_relative_location_path(xpath_ast_node* set)
		{
			xpath_ast_node* n = parse_step(set);
			if (!n) return 0;

			size_t old_depth = _depth;

			while (_lexer.current() == lex_slash || _lexer.current() == lex_double_slash)
			{
				lexeme_t l = _lexer.current();
				_lexer.next();

				if (l == lex_double_slash)
				{
					n = alloc_node(ast_step, n, axis_descendant_or_self, nodetest_type_node, 0);
					if (!n) return 0;

					++_depth;
				}

				if (++_depth > xpath_ast_depth_limit)
					return error_rec();

				n = parse_step(n);
				if (!n) return 0;
			}

			_depth = old_depth;

			return n;
		}

		// LocationPath ::= RelativeLocationPath | AbsoluteLocationPath
		// AbsoluteLocationPath ::= '/' RelativeLocationPath? | '//' RelativeLocationPath
		xpath_ast_node* parse_location_path()
		{
			if (_lexer.current() == lex_slash)
			{
				_lexer.next();

				xpath_ast_node* n = alloc_node(ast_step_root, xpath_type_node_set);
				if (!n) return 0;

				// relative location path can start from axis_attribute, dot, double_dot, multiply and string lexemes; any other lexeme means standalone root path
				lexeme_t l = _lexer.current();

				if (l == lex_string || l == lex_axis_attribute || l == lex_dot || l == lex_double_dot || l == lex_multiply)
					return parse_relative_location_path(n);
				else
					return n;
			}
			else if (_lexer.current() == lex_double_slash)
			{
				_lexer.next();

				xpath_ast_node* n = alloc_node(ast_step_root, xpath_type_node_set);
				if (!n) return 0;

				n = alloc_node(ast_step, n, axis_descendant_or_self, nodetest_type_node, 0);
				if (!n) return 0;

				return parse_relative_location_path(n);
			}

			// else clause moved outside of if because of bogus warning 'control may reach end of non-void function being inlined' in gcc 4.0.1
			return parse_relative_location_path(0);
		}

		// PathExpr ::= LocationPath
		//				| FilterExpr
		//				| FilterExpr '/' RelativeLocationPath
		//				| FilterExpr '//' RelativeLocationPath
		// UnionExpr ::= PathExpr | UnionExpr '|' PathExpr
		// UnaryExpr ::= UnionExpr | '-' UnaryExpr
		xpath_ast_node* parse_path_or_unary_expression()
		{
			// Clarification.
			// PathExpr begins with either LocationPath or FilterExpr.
			// FilterExpr begins with PrimaryExpr
			// PrimaryExpr begins with '$' in case of it being a variable reference,
			// '(' in case of it being an expression, string literal, number constant or
			// function call.
			if (_lexer.current() == lex_var_ref || _lexer.current() == lex_open_brace ||
				_lexer.current() == lex_quoted_string || _lexer.current() == lex_number ||
				_lexer.current() == lex_string)
			{
				if (_lexer.current() == lex_string)
				{
					// This is either a function call, or not - if not, we shall proceed with location path
					const char_t* state = _lexer.state();

					while (PUGI_IMPL_IS_CHARTYPE(*state, ct_space)) ++state;

					if (*state != '(')
						return parse_location_path();

					// This looks like a function call; however this still can be a node-test. Check it.
					if (parse_node_test_type(_lexer.contents()) != nodetest_none)
						return parse_location_path();
				}

				xpath_ast_node* n = parse_filter_expression();
				if (!n) return 0;

				if (_lexer.current() == lex_slash || _lexer.current() == lex_double_slash)
				{
					lexeme_t l = _lexer.current();
					_lexer.next();

					if (l == lex_double_slash)
					{
						if (n->rettype() != xpath_type_node_set)
							return error("Step has to be applied to node set");

						n = alloc_node(ast_step, n, axis_descendant_or_self, nodetest_type_node, 0);
						if (!n) return 0;
					}

					// select from location path
					return parse_relative_location_path(n);
				}

				return n;
			}
			else if (_lexer.current() == lex_minus)
			{
				_lexer.next();

				// precedence 7+ - only parses union expressions
				xpath_ast_node* n = parse_expression(7);
				if (!n) return 0;

				return alloc_node(ast_op_negate, xpath_type_number, n);
			}
			else
			{
				return parse_location_path();
			}
		}

		struct binary_op_t
		{
			ast_type_t asttype;
			xpath_value_type rettype;
			int precedence;

			binary_op_t(): asttype(ast_unknown), rettype(xpath_type_none), precedence(0)
			{
			}

			binary_op_t(ast_type_t asttype_, xpath_value_type rettype_, int precedence_): asttype(asttype_), rettype(rettype_), precedence(precedence_)
			{
			}

			static binary_op_t parse(xpath_lexer& lexer)
			{
				switch (lexer.current())
				{
				case lex_string:
					if (lexer.contents() == PUGIXML_TEXT("or"))
						return binary_op_t(ast_op_or, xpath_type_boolean, 1);
					else if (lexer.contents() == PUGIXML_TEXT("and"))
						return binary_op_t(ast_op_and, xpath_type_boolean, 2);
					else if (lexer.contents() == PUGIXML_TEXT("div"))
						return binary_op_t(ast_op_divide, xpath_type_number, 6);
					else if (lexer.contents() == PUGIXML_TEXT("mod"))
						return binary_op_t(ast_op_mod, xpath_type_number, 6);
					else
						return binary_op_t();

				case lex_equal:
					return binary_op_t(ast_op_equal, xpath_type_boolean, 3);

				case lex_not_equal:
					return binary_op_t(ast_op_not_equal, xpath_type_boolean, 3);

				case lex_less:
					return binary_op_t(ast_op_less, xpath_type_boolean, 4);

				case lex_greater:
					return binary_op_t(ast_op_greater, xpath_type_boolean, 4);

				case lex_less_or_equal:
					return binary_op_t(ast_op_less_or_equal, xpath_type_boolean, 4);

				case lex_greater_or_equal:
					return binary_op_t(ast_op_greater_or_equal, xpath_type_boolean, 4);

				case lex_plus:
					return binary_op_t(ast_op_add, xpath_type_number, 5);

				case lex_minus:
					return binary_op_t(ast_op_subtract, xpath_type_number, 5);

				case lex_multiply:
					return binary_op_t(ast_op_multiply, xpath_type_number, 6);

				case lex_union:
					return binary_op_t(ast_op_union, xpath_type_node_set, 7);

				default:
					return binary_op_t();
				}
			}
		};

		xpath_ast_node* parse_expression_rec(xpath_ast_node* lhs, int limit)
		{
			binary_op_t op = binary_op_t::parse(_lexer);

			while (op.asttype != ast_unknown && op.precedence >= limit)
			{
				_lexer.next();

				if (++_depth > xpath_ast_depth_limit)
					return error_rec();

				xpath_ast_node* rhs = parse_path_or_unary_expression();
				if (!rhs) return 0;

				binary_op_t nextop = binary_op_t::parse(_lexer);

				while (nextop.asttype != ast_unknown && nextop.precedence > op.precedence)
				{
					rhs = parse_expression_rec(rhs, nextop.precedence);
					if (!rhs) return 0;

					nextop = binary_op_t::parse(_lexer);
				}

				if (op.asttype == ast_op_union && (lhs->rettype() != xpath_type_node_set || rhs->rettype() != xpath_type_node_set))
					return error("Union operator has to be applied to node sets");

				lhs = alloc_node(op.asttype, op.rettype, lhs, rhs);
				if (!lhs) return 0;

				op = binary_op_t::parse(_lexer);
			}

			return lhs;
		}

		// Expr ::= OrExpr
		// OrExpr ::= AndExpr | OrExpr 'or' AndExpr
		// AndExpr ::= EqualityExpr | AndExpr 'and' EqualityExpr
		// EqualityExpr ::= RelationalExpr
		//					| EqualityExpr '=' RelationalExpr
		//					| EqualityExpr '!=' RelationalExpr
		// RelationalExpr ::= AdditiveExpr
		//					  | RelationalExpr '<' AdditiveExpr
		//					  | RelationalExpr '>' AdditiveExpr
		//					  | RelationalExpr '<=' AdditiveExpr
		//					  | RelationalExpr '>=' AdditiveExpr
		// AdditiveExpr ::= MultiplicativeExpr
		//					| AdditiveExpr '+' MultiplicativeExpr
		//					| AdditiveExpr '-' MultiplicativeExpr
		// MultiplicativeExpr ::= UnaryExpr
		//						  | MultiplicativeExpr '*' UnaryExpr
		//						  | MultiplicativeExpr 'div' UnaryExpr
		//						  | MultiplicativeExpr 'mod' UnaryExpr
		xpath_ast_node* parse_expression(int limit = 0)
		{
			size_t old_depth = _depth;

			if (++_depth > xpath_ast_depth_limit)
				return error_rec();

			xpath_ast_node* n = parse_path_or_unary_expression();
			if (!n) return 0;

			n = parse_expression_rec(n, limit);

			_depth = old_depth;

			return n;
		}

		xpath_parser(const char_t* query, xpath_variable_set* variables, xpath_allocator* alloc, xpath_parse_result* result): _alloc(alloc), _lexer(query), _query(query), _variables(variables), _result(result), _depth(0)
		{
		}

		xpath_ast_node* parse()
		{
			xpath_ast_node* n = parse_expression();
			if (!n) return 0;

			assert(_depth == 0);

			// check if there are unparsed tokens left
			if (_lexer.current() != lex_eof)
				return error("Incorrect query");

			return n;
		}

		static xpath_ast_node* parse(const char_t* query, xpath_variable_set* variables, xpath_allocator* alloc, xpath_parse_result* result)
		{
			xpath_parser parser(query, variables, alloc, result);

			return parser.parse();
		}
	};

	struct xpath_query_impl
	{
		static xpath_query_impl* create()
		{
			void* memory = xml_memory::allocate(sizeof(xpath_query_impl));
			if (!memory) return 0;

			return new (memory) xpath_query_impl();
		}

		static void destroy(xpath_query_impl* impl)
		{
			// free all allocated pages
			impl->alloc.release();

			// free allocator memory (with the first page)
			xml_memory::deallocate(impl);
		}

		xpath_query_impl(): root(0), alloc(&block, &oom), oom(false)
		{
			block.next = 0;
			block.capacity = sizeof(block.data);
		}

		xpath_ast_node* root;
		xpath_allocator alloc;
		xpath_memory_block block;
		bool oom;
	};

	PUGI_IMPL_FN impl::xpath_ast_node* evaluate_node_set_prepare(xpath_query_impl* impl)
	{
		if (!impl) return 0;

		if (impl->root->rettype() != xpath_type_node_set)
		{
		#ifdef PUGIXML_NO_EXCEPTIONS
			return 0;
		#else
			xpath_parse_result res;
			res.error = "Expression does not evaluate to node set";

			throw xpath_exception(res);
		#endif
		}

		return impl->root;
	}
PUGI_IMPL_NS_END

namespace pugi
{
#ifndef PUGIXML_NO_EXCEPTIONS
	PUGI_IMPL_FN xpath_exception::xpath_exception(const xpath_parse_result& result_): _result(result_)
	{
		assert(_result.error);
	}

	PUGI_IMPL_FN const char* xpath_exception::what() const throw()
	{
		return _result.error;
	}

	PUGI_IMPL_FN const xpath_parse_result& xpath_exception::result() const
	{
		return _result;
	}
#endif

	PUGI_IMPL_FN xpath_node::xpath_node()
	{
	}

	PUGI_IMPL_FN xpath_node::xpath_node(const xml_node& node_): _node(node_)
	{
	}

	PUGI_IMPL_FN xpath_node::xpath_node(const xml_attribute& attribute_, const xml_node& parent_): _node(attribute_ ? parent_ : xml_node()), _attribute(attribute_)
	{
	}

	PUGI_IMPL_FN xml_node xpath_node::node() const
	{
		return _attribute ? xml_node() : _node;
	}

	PUGI_IMPL_FN xml_attribute xpath_node::attribute() const
	{
		return _attribute;
	}

	PUGI_IMPL_FN xml_node xpath_node::parent() const
	{
		return _attribute ? _node : _node.parent();
	}

	PUGI_IMPL_FN static void unspecified_bool_xpath_node(xpath_node***)
	{
	}

	PUGI_IMPL_FN xpath_node::operator xpath_node::unspecified_bool_type() const
	{
		return (_node || _attribute) ? unspecified_bool_xpath_node : 0;
	}

	PUGI_IMPL_FN bool xpath_node::operator!() const
	{
		return !(_node || _attribute);
	}

	PUGI_IMPL_FN bool xpath_node::operator==(const xpath_node& n) const
	{
		return _node == n._node && _attribute == n._attribute;
	}

	PUGI_IMPL_FN bool xpath_node::operator!=(const xpath_node& n) const
	{
		return _node != n._node || _attribute != n._attribute;
	}

#ifdef __BORLANDC__
	PUGI_IMPL_FN bool operator&&(const xpath_node& lhs, bool rhs)
	{
		return (bool)lhs && rhs;
	}

	PUGI_IMPL_FN bool operator||(const xpath_node& lhs, bool rhs)
	{
		return (bool)lhs || rhs;
	}
#endif

	PUGI_IMPL_FN void xpath_node_set::_assign(const_iterator begin_, const_iterator end_, type_t type_)
	{
		assert(begin_ <= end_);

		size_t size_ = static_cast<size_t>(end_ - begin_);

		// use internal buffer for 0 or 1 elements, heap buffer otherwise
		xpath_node* storage = (size_ <= 1) ? _storage : static_cast<xpath_node*>(impl::xml_memory::allocate(size_ * sizeof(xpath_node)));

		if (!storage)
		{
		#ifdef PUGIXML_NO_EXCEPTIONS
			return;
		#else
			throw std::bad_alloc();
		#endif
		}

		// deallocate old buffer
		if (_begin != _storage)
			impl::xml_memory::deallocate(_begin);

		// size check is necessary because for begin_ = end_ = nullptr, memcpy is UB
		if (size_)
			memcpy(storage, begin_, size_ * sizeof(xpath_node));

		_begin = storage;
		_end = storage + size_;
		_type = type_;
	}

#ifdef PUGIXML_HAS_MOVE
	PUGI_IMPL_FN void xpath_node_set::_move(xpath_node_set& rhs) PUGIXML_NOEXCEPT
	{
		_type = rhs._type;
		_storage[0] = rhs._storage[0];
		_begin = (rhs._begin == rhs._storage) ? _storage : rhs._begin;
		_end = _begin + (rhs._end - rhs._begin);

		rhs._type = type_unsorted;
		rhs._begin = rhs._storage;
		rhs._end = rhs._storage;
	}
#endif

	PUGI_IMPL_FN xpath_node_set::xpath_node_set(): _type(type_unsorted), _begin(_storage), _end(_storage)
	{
	}

	PUGI_IMPL_FN xpath_node_set::xpath_node_set(const_iterator begin_, const_iterator end_, type_t type_): _type(type_unsorted), _begin(_storage), _end(_storage)
	{
		_assign(begin_, end_, type_);
	}

	PUGI_IMPL_FN xpath_node_set::~xpath_node_set()
	{
		if (_begin != _storage)
			impl::xml_memory::deallocate(_begin);
	}

	PUGI_IMPL_FN xpath_node_set::xpath_node_set(const xpath_node_set& ns): _type(type_unsorted), _begin(_storage), _end(_storage)
	{
		_assign(ns._begin, ns._end, ns._type);
	}

	PUGI_IMPL_FN xpath_node_set& xpath_node_set::operator=(const xpath_node_set& ns)
	{
		if (this == &ns) return *this;

		_assign(ns._begin, ns._end, ns._type);

		return *this;
	}

#ifdef PUGIXML_HAS_MOVE
	PUGI_IMPL_FN xpath_node_set::xpath_node_set(xpath_node_set&& rhs) PUGIXML_NOEXCEPT: _type(type_unsorted), _begin(_storage), _end(_storage)
	{
		_move(rhs);
	}

	PUGI_IMPL_FN xpath_node_set& xpath_node_set::operator=(xpath_node_set&& rhs) PUGIXML_NOEXCEPT
	{
		if (this == &rhs) return *this;

		if (_begin != _storage)
			impl::xml_memory::deallocate(_begin);

		_move(rhs);

		return *this;
	}
#endif

	PUGI_IMPL_FN xpath_node_set::type_t xpath_node_set::type() const
	{
		return _type;
	}

	PUGI_IMPL_FN size_t xpath_node_set::size() const
	{
		return _end - _begin;
	}

	PUGI_IMPL_FN bool xpath_node_set::empty() const
	{
		return _begin == _end;
	}

	PUGI_IMPL_FN const xpath_node& xpath_node_set::operator[](size_t index) const
	{
		assert(index < size());
		return _begin[index];
	}

	PUGI_IMPL_FN xpath_node_set::const_iterator xpath_node_set::begin() const
	{
		return _begin;
	}

	PUGI_IMPL_FN xpath_node_set::const_iterator xpath_node_set::end() const
	{
		return _end;
	}

	PUGI_IMPL_FN void xpath_node_set::sort(bool reverse)
	{
		_type = impl::xpath_sort(_begin, _end, _type, reverse);
	}

	PUGI_IMPL_FN xpath_node xpath_node_set::first() const
	{
		return impl::xpath_first(_begin, _end, _type);
	}

	PUGI_IMPL_FN xpath_parse_result::xpath_parse_result(): error("Internal error"), offset(0)
	{
	}

	PUGI_IMPL_FN xpath_parse_result::operator bool() const
	{
		return error == 0;
	}

	PUGI_IMPL_FN const char* xpath_parse_result::description() const
	{
		return error ? error : "No error";
	}

	PUGI_IMPL_FN xpath_variable::xpath_variable(xpath_value_type type_): _type(type_), _next(0)
	{
	}

	PUGI_IMPL_FN const char_t* xpath_variable::name() const
	{
		switch (_type)
		{
		case xpath_type_node_set:
			return static_cast<const impl::xpath_variable_node_set*>(this)->name;

		case xpath_type_number:
			return static_cast<const impl::xpath_variable_number*>(this)->name;

		case xpath_type_string:
			return static_cast<const impl::xpath_variable_string*>(this)->name;

		case xpath_type_boolean:
			return static_cast<const impl::xpath_variable_boolean*>(this)->name;

		default:
			assert(false && "Invalid variable type"); // unreachable
			return 0;
		}
	}

	PUGI_IMPL_FN xpath_value_type xpath_variable::type() const
	{
		return _type;
	}

	PUGI_IMPL_FN bool xpath_variable::get_boolean() const
	{
		return (_type == xpath_type_boolean) ? static_cast<const impl::xpath_variable_boolean*>(this)->value : false;
	}

	PUGI_IMPL_FN double xpath_variable::get_number() const
	{
		return (_type == xpath_type_number) ? static_cast<const impl::xpath_variable_number*>(this)->value : impl::gen_nan();
	}

	PUGI_IMPL_FN const char_t* xpath_variable::get_string() const
	{
		const char_t* value = (_type == xpath_type_string) ? static_cast<const impl::xpath_variable_string*>(this)->value : 0;
		return value ? value : PUGIXML_TEXT("");
	}

	PUGI_IMPL_FN const xpath_node_set& xpath_variable::get_node_set() const
	{
		return (_type == xpath_type_node_set) ? static_cast<const impl::xpath_variable_node_set*>(this)->value : impl::dummy_node_set;
	}

	PUGI_IMPL_FN bool xpath_variable::set(bool value)
	{
		if (_type != xpath_type_boolean) return false;

		static_cast<impl::xpath_variable_boolean*>(this)->value = value;
		return true;
	}

	PUGI_IMPL_FN bool xpath_variable::set(double value)
	{
		if (_type != xpath_type_number) return false;

		static_cast<impl::xpath_variable_number*>(this)->value = value;
		return true;
	}

	PUGI_IMPL_FN bool xpath_variable::set(const char_t* value)
	{
		if (_type != xpath_type_string) return false;

		impl::xpath_variable_string* var = static_cast<impl::xpath_variable_string*>(this);

		// duplicate string
		size_t size = (impl::strlength(value) + 1) * sizeof(char_t);

		char_t* copy = static_cast<char_t*>(impl::xml_memory::allocate(size));
		if (!copy) return false;

		memcpy(copy, value, size);

		// replace old string
		if (var->value) impl::xml_memory::deallocate(var->value);
		var->value = copy;

		return true;
	}

	PUGI_IMPL_FN bool xpath_variable::set(const xpath_node_set& value)
	{
		if (_type != xpath_type_node_set) return false;

		static_cast<impl::xpath_variable_node_set*>(this)->value = value;
		return true;
	}

	PUGI_IMPL_FN xpath_variable_set::xpath_variable_set()
	{
		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
			_data[i] = 0;
	}

	PUGI_IMPL_FN xpath_variable_set::~xpath_variable_set()
	{
		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
			_destroy(_data[i]);
	}

	PUGI_IMPL_FN xpath_variable_set::xpath_variable_set(const xpath_variable_set& rhs)
	{
		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
			_data[i] = 0;

		_assign(rhs);
	}

	PUGI_IMPL_FN xpath_variable_set& xpath_variable_set::operator=(const xpath_variable_set& rhs)
	{
		if (this == &rhs) return *this;

		_assign(rhs);

		return *this;
	}

#ifdef PUGIXML_HAS_MOVE
	PUGI_IMPL_FN xpath_variable_set::xpath_variable_set(xpath_variable_set&& rhs) PUGIXML_NOEXCEPT
	{
		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
		{
			_data[i] = rhs._data[i];
			rhs._data[i] = 0;
		}
	}

	PUGI_IMPL_FN xpath_variable_set& xpath_variable_set::operator=(xpath_variable_set&& rhs) PUGIXML_NOEXCEPT
	{
		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
		{
			_destroy(_data[i]);

			_data[i] = rhs._data[i];
			rhs._data[i] = 0;
		}

		return *this;
	}
#endif

	PUGI_IMPL_FN void xpath_variable_set::_assign(const xpath_variable_set& rhs)
	{
		xpath_variable_set temp;

		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
			if (rhs._data[i] && !_clone(rhs._data[i], &temp._data[i]))
				return;

		_swap(temp);
	}

	PUGI_IMPL_FN void xpath_variable_set::_swap(xpath_variable_set& rhs)
	{
		for (size_t i = 0; i < sizeof(_data) / sizeof(_data[0]); ++i)
		{
			xpath_variable* chain = _data[i];

			_data[i] = rhs._data[i];
			rhs._data[i] = chain;
		}
	}

	PUGI_IMPL_FN xpath_variable* xpath_variable_set::_find(const char_t* name) const
	{
		const size_t hash_size = sizeof(_data) / sizeof(_data[0]);
		size_t hash = impl::hash_string(name) % hash_size;

		// look for existing variable
		for (xpath_variable* var = _data[hash]; var; var = var->_next)
			if (impl::strequal(var->name(), name))
				return var;

		return 0;
	}

	PUGI_IMPL_FN bool xpath_variable_set::_clone(xpath_variable* var, xpath_variable** out_result)
	{
		xpath_variable* last = 0;

		while (var)
		{
			// allocate storage for new variable
			xpath_variable* nvar = impl::new_xpath_variable(var->_type, var->name());
			if (!nvar) return false;

			// link the variable to the result immediately to handle failures gracefully
			if (last)
				last->_next = nvar;
			else
				*out_result = nvar;

			last = nvar;

			// copy the value; this can fail due to out-of-memory conditions
			if (!impl::copy_xpath_variable(nvar, var)) return false;

			var = var->_next;
		}

		return true;
	}

	PUGI_IMPL_FN void xpath_variable_set::_destroy(xpath_variable* var)
	{
		while (var)
		{
			xpath_variable* next = var->_next;

			impl::delete_xpath_variable(var->_type, var);

			var = next;
		}
	}

	PUGI_IMPL_FN xpath_variable* xpath_variable_set::add(const char_t* name, xpath_value_type type)
	{
		const size_t hash_size = sizeof(_data) / sizeof(_data[0]);
		size_t hash = impl::hash_string(name) % hash_size;

		// look for existing variable
		for (xpath_variable* var = _data[hash]; var; var = var->_next)
			if (impl::strequal(var->name(), name))
				return var->type() == type ? var : 0;

		// add new variable
		xpath_variable* result = impl::new_xpath_variable(type, name);

		if (result)
		{
			result->_next = _data[hash];

			_data[hash] = result;
		}

		return result;
	}

	PUGI_IMPL_FN bool xpath_variable_set::set(const char_t* name, bool value)
	{
		xpath_variable* var = add(name, xpath_type_boolean);
		return var ? var->set(value) : false;
	}

	PUGI_IMPL_FN bool xpath_variable_set::set(const char_t* name, double value)
	{
		xpath_variable* var = add(name, xpath_type_number);
		return var ? var->set(value) : false;
	}

	PUGI_IMPL_FN bool xpath_variable_set::set(const char_t* name, const char_t* value)
	{
		xpath_variable* var = add(name, xpath_type_string);
		return var ? var->set(value) : false;
	}

	PUGI_IMPL_FN bool xpath_variable_set::set(const char_t* name, const xpath_node_set& value)
	{
		xpath_variable* var = add(name, xpath_type_node_set);
		return var ? var->set(value) : false;
	}

	PUGI_IMPL_FN xpath_variable* xpath_variable_set::get(const char_t* name)
	{
		return _find(name);
	}

	PUGI_IMPL_FN const xpath_variable* xpath_variable_set::get(const char_t* name) const
	{
		return _find(name);
	}

	PUGI_IMPL_FN xpath_query::xpath_query(const char_t* query, xpath_variable_set* variables): _impl(0)
	{
		impl::xpath_query_impl* qimpl = impl::xpath_query_impl::create();

		if (!qimpl)
		{
		#ifdef PUGIXML_NO_EXCEPTIONS
			_result.error = "Out of memory";
		#else
			throw std::bad_alloc();
		#endif
		}
		else
		{
			using impl::auto_deleter; // MSVC7 workaround
			auto_deleter<impl::xpath_query_impl> impl(qimpl, impl::xpath_query_impl::destroy);

			qimpl->root = impl::xpath_parser::parse(query, variables, &qimpl->alloc, &_result);

			if (qimpl->root)
			{
				qimpl->root->optimize(&qimpl->alloc);

				_impl = impl.release();
				_result.error = 0;
			}
			else
			{
			#ifdef PUGIXML_NO_EXCEPTIONS
				if (qimpl->oom) _result.error = "Out of memory";
			#else
				if (qimpl->oom) throw std::bad_alloc();
				throw xpath_exception(_result);
			#endif
			}
		}
	}

	PUGI_IMPL_FN xpath_query::xpath_query(): _impl(0)
	{
	}

	PUGI_IMPL_FN xpath_query::~xpath_query()
	{
		if (_impl)
			impl::xpath_query_impl::destroy(static_cast<impl::xpath_query_impl*>(_impl));
	}

#ifdef PUGIXML_HAS_MOVE
	PUGI_IMPL_FN xpath_query::xpath_query(xpath_query&& rhs) PUGIXML_NOEXCEPT
	{
		_impl = rhs._impl;
		_result = rhs._result;
		rhs._impl = 0;
		rhs._result = xpath_parse_result();
	}

	PUGI_IMPL_FN xpath_query& xpath_query::operator=(xpath_query&& rhs) PUGIXML_NOEXCEPT
	{
		if (this == &rhs) return *this;

		if (_impl)
			impl::xpath_query_impl::destroy(static_cast<impl::xpath_query_impl*>(_impl));

		_impl = rhs._impl;
		_result = rhs._result;
		rhs._impl = 0;
		rhs._result = xpath_parse_result();

		return *this;
	}
#endif

	PUGI_IMPL_FN xpath_value_type xpath_query::return_type() const
	{
		if (!_impl) return xpath_type_none;

		return static_cast<impl::xpath_query_impl*>(_impl)->root->rettype();
	}

	PUGI_IMPL_FN bool xpath_query::evaluate_boolean(const xpath_node& n) const
	{
		if (!_impl) return false;

		impl::xpath_context c(n, 1, 1);
		impl::xpath_stack_data sd;

		bool r = static_cast<impl::xpath_query_impl*>(_impl)->root->eval_boolean(c, sd.stack);

		if (sd.oom)
		{
		#ifdef PUGIXML_NO_EXCEPTIONS
			return false;
		#else
			throw std::bad_alloc();
		#endif
		}

		return r;
	}

	PUGI_IMPL_FN double xpath_query::evaluate_number(const xpath_node& n) const
	{
		if (!_impl) return impl::gen_nan();

		impl::xpath_context c(n, 1, 1);
		impl::xpath_stack_data sd;

		double r = static_cast<impl::xpath_query_impl*>(_impl)->root->eval_number(c, sd.stack);

		if (sd.oom)
		{
		#ifdef PUGIXML_NO_EXCEPTIONS
			return impl::gen_nan();
		#else
			throw std::bad_alloc();
		#endif
		}

		return r;
	}

#ifndef PUGIXML_NO_STL
	PUGI_IMPL_FN string_t xpath_query::evaluate_string(const xpath_node& n) const
	{
		if (!_impl) return string_t();

		impl::xpath_context c(n, 1, 1);
		impl::xpath_stack_data sd;

		impl::xpath_string r = static_cast<impl::xpath_query_impl*>(_impl)->root->eval_string(c, sd.stack);

		if (sd.oom)
		{
		#ifdef PUGIXML_NO_EXCEPTIONS
			return string_t();
		#else
			throw std::bad_alloc();
		#endif
		}

		return string_t(r.c_str(), r.length());
	}
#endif

	PUGI_IMPL_FN size_t xpath_query::evaluate_string(char_t* buffer, size_t capacity, const xpath_node& n) const
	{
		impl::xpath_context c(n, 1, 1);
		impl::xpath_stack_data sd;

		impl::xpath_string r = _impl ? static_cast<impl::xpath_query_impl*>(_impl)->root->eval_string(c, sd.stack) : impl::xpath_string();

		if (sd.oom)
		{
		#ifdef PUGIXML_NO_EXCEPTIONS
			r = impl::xpath_string();
		#else
			throw std::bad_alloc();
		#endif
		}

		size_t full_size = r.length() + 1;

		if (capacity > 0)
		{
			size_t size = (full_size < capacity) ? full_size : capacity;
			assert(size > 0);

			memcpy(buffer, r.c_str(), (size - 1) * sizeof(char_t));
			buffer[size - 1] = 0;
		}

		return full_size;
	}

	PUGI_IMPL_FN xpath_node_set xpath_query::evaluate_node_set(const xpath_node& n) const
	{
		impl::xpath_ast_node* root = impl::evaluate_node_set_prepare(static_cast<impl::xpath_query_impl*>(_impl));
		if (!root) return xpath_node_set();

		impl::xpath_context c(n, 1, 1);
		impl::xpath_stack_data sd;

		impl::xpath_node_set_raw r = root->eval_node_set(c, sd.stack, impl::nodeset_eval_all);

		if (sd.oom)
		{
		#ifdef PUGIXML_NO_EXCEPTIONS
			return xpath_node_set();
		#else
			throw std::bad_alloc();
		#endif
		}

		return xpath_node_set(r.begin(), r.end(), r.type());
	}

	PUGI_IMPL_FN xpath_node xpath_query::evaluate_node(const xpath_node& n) const
	{
		impl::xpath_ast_node* root = impl::evaluate_node_set_prepare(static_cast<impl::xpath_query_impl*>(_impl));
		if (!root) return xpath_node();

		impl::xpath_context c(n, 1, 1);
		impl::xpath_stack_data sd;

		impl::xpath_node_set_raw r = root->eval_node_set(c, sd.stack, impl::nodeset_eval_first);

		if (sd.oom)
		{
		#ifdef PUGIXML_NO_EXCEPTIONS
			return xpath_node();
		#else
			throw std::bad_alloc();
		#endif
		}

		return r.first();
	}

	PUGI_IMPL_FN const xpath_parse_result& xpath_query::result() const
	{
		return _result;
	}

	PUGI_IMPL_FN static void unspecified_bool_xpath_query(xpath_query***)
	{
	}

	PUGI_IMPL_FN xpath_query::operator xpath_query::unspecified_bool_type() const
	{
		return _impl ? unspecified_bool_xpath_query : 0;
	}

	PUGI_IMPL_FN bool xpath_query::operator!() const
	{
		return !_impl;
	}

	PUGI_IMPL_FN xpath_node xml_node::select_node(const char_t* query, xpath_variable_set* variables) const
	{
		xpath_query q(query, variables);
		return q.evaluate_node(*this);
	}

	PUGI_IMPL_FN xpath_node xml_node::select_node(const xpath_query& query) const
	{
		return query.evaluate_node(*this);
	}

	PUGI_IMPL_FN xpath_node_set xml_node::select_nodes(const char_t* query, xpath_variable_set* variables) const
	{
		xpath_query q(query, variables);
		return q.evaluate_node_set(*this);
	}

	PUGI_IMPL_FN xpath_node_set xml_node::select_nodes(const xpath_query& query) const
	{
		return query.evaluate_node_set(*this);
	}

	PUGI_IMPL_FN xpath_node xml_node::select_single_node(const char_t* query, xpath_variable_set* variables) const
	{
		xpath_query q(query, variables);
		return q.evaluate_node(*this);
	}

	PUGI_IMPL_FN xpath_node xml_node::select_single_node(const xpath_query& query) const
	{
		return query.evaluate_node(*this);
	}
}

#endif

#ifdef __BORLANDC__
#	pragma option pop
#endif

// Intel C++ does not properly keep warning state for function templates,
// so popping warning state at the end of translation unit leads to warnings in the middle.
#if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
#	pragma warning(pop)
#endif

#if defined(_MSC_VER) && defined(__c2__)
#	pragma clang diagnostic pop
#endif

// Undefine all local macros (makes sure we're not leaking macros in header-only mode)
#undef PUGI_IMPL_NO_INLINE
#undef PUGI_IMPL_UNLIKELY
#undef PUGI_IMPL_STATIC_ASSERT
#undef PUGI_IMPL_DMC_VOLATILE
#undef PUGI_IMPL_UNSIGNED_OVERFLOW
#undef PUGI_IMPL_MSVC_CRT_VERSION
#undef PUGI_IMPL_SNPRINTF
#undef PUGI_IMPL_NS_BEGIN
#undef PUGI_IMPL_NS_END
#undef PUGI_IMPL_FN
#undef PUGI_IMPL_FN_NO_INLINE
#undef PUGI_IMPL_GETHEADER_IMPL
#undef PUGI_IMPL_GETPAGE_IMPL
#undef PUGI_IMPL_GETPAGE
#undef PUGI_IMPL_NODETYPE
#undef PUGI_IMPL_IS_CHARTYPE_IMPL
#undef PUGI_IMPL_IS_CHARTYPE
#undef PUGI_IMPL_IS_CHARTYPEX
#undef PUGI_IMPL_ENDSWITH
#undef PUGI_IMPL_SKIPWS
#undef PUGI_IMPL_OPTSET
#undef PUGI_IMPL_PUSHNODE
#undef PUGI_IMPL_POPNODE
#undef PUGI_IMPL_SCANFOR
#undef PUGI_IMPL_SCANWHILE
#undef PUGI_IMPL_SCANWHILE_UNROLL
#undef PUGI_IMPL_ENDSEG
#undef PUGI_IMPL_THROW_ERROR
#undef PUGI_IMPL_CHECK_ERROR

#endif

/**
 * Copyright (c) 2006-2023 Arseny Kapoulkine
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use,
 * copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following
 * conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */