docs: Extracted Installation section, minor fixes/clarifications, added loading intro and load_file documentation

git-svn-id: http://pugixml.googlecode.com/svn/trunk@541 99668b35-9821-0410-8761-19e4c4f06640

1 files changed, 178 insertions, 115 deletions

diff --git a/docs/manual.qbk b/docs/manual.qbk
index 81a89df..bd3f68e 100644
--- a/docs/manual.qbk
+++ b/docs/manual.qbk
@@ -13,6 +13,8 @@
 

 PugiXML User Manual

 

+[section:overview Overview]

+

 [section:introduction Introduction]

 

 $$$ minimalistic/lightweight; why should the user choose pugixml

@@ -21,13 +23,111 @@ $$$ unicode support
 $$$ low memory consumption and fragmentation

 $$$ this is the ref manual; here is the quick-start guide, here are the code samples

 

-pugixml is a C++ XML $$processing library$$. It consists of a DOM-like interface with rich traversal/modification capabilities, an extremely fast XML parser which constructs the DOM tree from an XML file/buffer, and a XPath 1.0 implementation for complex data-driven tree queries. The library is [link manual.overview.portability extremely portable] and easy to integrate and use. pugixml is developed and maintained since 2006 and has ^many users^. All code is distributed under the MIT license, making it completely free to use even in commercial applications.

+pugixml is a C++ XML $$processing library$$. It consists of a DOM-like interface with rich traversal/modification capabilities, an extremely fast XML parser which constructs the DOM tree from an XML file/buffer, and a XPath 1.0 implementation for complex data-driven tree queries. The library is [link manual.install.portability extremely portable] and easy to integrate and use. pugixml is developed and maintained since 2006 and has ^many users^. All code is distributed under the MIT license, making it completely free to use even in commercial applications.

 

 Please note that pugixml's parser is a non-validating one; if you either need to process XML documents that do not fit in memory or need DTD/Schema validation, the library is not for you.

 

 [endsect] [/introduction]

 

-[section:overview Overview]

+[section:feedback Feedback]

+

+If you believe you've found a bug in pugixml (bugs include compilation problems (errors/warnings), crashes, performance degradation and incorrect behavior), please file an issue via [@http://code.google.com/p/pugixml/issues/entry issue submission form]. Be sure to include the relevant information so that the bug can be reproduced: the version of pugixml, compiler version and target architecture, the code that uses pugixml and exhibits the bug, etc.

+

+Feature requests can be reported the same way as bugs, so if you're missing some functionality in pugixml or if the API is rough in some places and you can suggest an improvement, file an issue. However please note that there are many factors when considering API changes (compatibility with previous versions, API redundancy, etc.), so generally features that can be implemented via a small function without pugixml modification are not accepted. However, all rules have exceptions.

+

+If you have a contribution to pugixml, such as build script for some build system/IDE, or a well-designed set of helper functions, or a binding to some language other than C++, please file an issue. You can include the relevant patches as issue attachments. Your contribution has to be distributed under the terms of a license that's compatible with pugixml license; i.e. GPL/LGPL licensed code is not accepted.

+

+[#email]

+If filing an issue is not possible due to privacy or other concerns, you can contact pugixml author by e-mail directly: [@mailto:arseny.kapoulkine@gmail.com arseny.kapoulkine@gmail.com].

+

+[endsect] [/feedback]

+

+[section:changelog Changelog]

+

+Only changes since version 0.5 are listed here; you can [@changes.txt view the full changelog here].

+ 

+Version 0.9:

+

+* Major Unicode improvements:

+	# Introduced encoding support (automatic/manual encoding detection on load, manual encoding selection on save, conversion from/to UTF8, UTF16 LE/BE, UTF32 LE/BE) 

+	# Introduced wchar_t mode (you can set PUGIXML_WCHAR_MODE define to switch pugixml internal encoding from UTF8 to wchar_t; all functions are switched to their Unicode variants) 

+	# Load/save functions now support wide streams

+

+* Bug fixes:

+	# Fixed document corruption on failed parsing bug 

+	# XPath string <-> number conversion improvements (increased precision, fixed crash for huge numbers) 

+	# Improved DOCTYPE parsing: now parser recognizes all well-formed DOCTYPE declarations 

+	# Fixed xml_attribute::as_uint() for large numbers (i.e. 2^32-1)

+

+* Specification changes:

+	# parse() API changed to load_buffer/load_buffer_inplace/load_buffer_inplace_own; load_buffer APIs do not require zero-terminated strings. 

+	# Renamed as_utf16 to as_wide 

+	# Changed xml_node::offset_debug return type and xml_parse_result::offset type to ptrdiff_t 

+	# Nodes/attributes with empty names are now printed as :anonymous

+

+* Performance improvements:

+	# Optimized document parsing and saving 

+	# Changed internal memory management: internal allocator is used for both metadata and name/value data; allocated pages are deleted if all allocations from them are deleted 

+	# Optimized memory consumption: sizeof(xml_node_struct) reduced from 40 bytes to 32 bytes on x86 

+	# Optimized debug mode parsing/saving by order of magnitude

+

+* Miscellaneous:

+	# All STL includes except <exception> in pugixml.hpp are replaced with forward declarations

+

+* Compatibility:

+	# parse() and as_utf16 are left for compatibility (these functions are deprecated and will be removed in pugixml-1.0) 

+	# Wildcard functions, document_order/precompute_document_order functions, format_write_bom_utf8 and parse_wnorm_attribute flags are deprecated and will be removed in version 1.0 

+

+[endsect] [/changelog]

+

+[section:thanks Acknowledgments]

+

+pugixml could not be developed without the help from many people; some of them are listed in this section. If you've played a part in pugixml development and you can not find yourself on this list, I'm truly sorry; please [link email send me an e-mail] so I can fix this.

+

+Thanks to *Kristen Wegner* for pugxml parser, which was used as a basis for pugixml.

+

+Thanks to *Neville Franks* for contributions to pugxml parser.

+

+Thanks to *Artyom Palvelev* for suggesting a lazy gap contraction approach.

+

+Thanks to *Vyacheslav Egorov* for documentation proofreading.

+

+[endsect] [/thanks]

+

+[section:license License]

+

+The pugixml library is distributed under the MIT license:

+

+[pre

+Copyright (c) 2006-2010 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.

+]

+

+[endsect] [/license]

+

+[endsect] [/overview]

+ 

+[section:install Installation]

 

 [section:getting Getting pugixml]

 

@@ -72,7 +172,7 @@ Use latest version tag if you want to automatically get new versions via =svn up
 

 pugixml is distributed in source form without any pre-built binaries; you have to build them yourself.

  

-The complete pugixml source consists of four files - two source files, [file pugixml.cpp] and [file pugixpath.cpp], and two header files, [file pugixml.hpp] and [file pugiconfig.hpp]. [file pugixml.hpp] is the primary header which you need to include in order to use pugixml classes/functions; [file pugiconfig.hpp] is a supplementary configuration file (see [link manual.overview.building.config]). The rest of this guide assumes that [file pugixml.hpp] is either in the current directory or in one of include directories of your projects, so that `#include "pugixml.hpp"` can find the header; however you can also use relative path (i.e. `#include "../libs/pugixml/src/pugixml.hpp"`) or include directory-relative path (i.e. `#include <xml/thirdparty/pugixml/src/pugixml.hpp>`).

+The complete pugixml source consists of four files - two source files, [file pugixml.cpp] and [file pugixpath.cpp], and two header files, [file pugixml.hpp] and [file pugiconfig.hpp]. [file pugixml.hpp] is the primary header which you need to include in order to use pugixml classes/functions; [file pugiconfig.hpp] is a supplementary configuration file (see [link manual.install.building.config]). The rest of this guide assumes that [file pugixml.hpp] is either in the current directory or in one of include directories of your projects, so that `#include "pugixml.hpp"` can find the header; however you can also use relative path (i.e. `#include "../libs/pugixml/src/pugixml.hpp"`) or include directory-relative path (i.e. `#include <xml/thirdparty/pugixml/src/pugixml.hpp>`).

  

 [note You don't need to compile [file pugixpath.cpp] unless you use XPath.]

 

@@ -149,7 +249,7 @@ pugixml uses several defines to control the compilation process. There are two w
 

 [note As of version 0.9, exceptions are *only* used in XPath implementation; therefore, XPath is also disabled if this macro is defined. This will change in version 1.0.]

 

-`PUGIXML_API`, `PUGIXML_CLASS` and `PUGIXML_FUNCTION` defines let you specify custom attributes (i.e. declspec or calling conventions) for pugixml classes and non-member functions. In absence of `PUGIXML_CLASS` or `PUGIXML_FUNCTION` definitions, `PUGIXML_API` definition is used instead. For example, to specify fixed calling convention, you can define `PUGIXML_FUNCTION` to i.e. `__fastcall`. Another example is DLL import/export attributes in MSVC (see [link manual.overview.building.shared]).

+`PUGIXML_API`, `PUGIXML_CLASS` and `PUGIXML_FUNCTION` defines let you specify custom attributes (i.e. declspec or calling conventions) for pugixml classes and non-member functions. In absence of `PUGIXML_CLASS` or `PUGIXML_FUNCTION` definitions, `PUGIXML_API` definition is used instead. For example, to specify fixed calling convention, you can define `PUGIXML_FUNCTION` to i.e. `__fastcall`. Another example is DLL import/export attributes in MSVC (see [link manual.install.building.shared]).

 

 [note In that example `PUGIXML_API` is inconsistent between several source files; this is an exception to the consistency rule.]

  

@@ -179,104 +279,8 @@ pugixml is written in standard-compliant C++ with some compiler-specific workaro
 

 [endsect] [/portability]

 

-[section:feedback Feedback]

-

-If you believe you've found a bug in pugixml (bugs include compilation problems (errors/warnings), crashes, performance degradation and incorrect behavior), please file an issue via [@http://code.google.com/p/pugixml/issues/entry issue submission form]. Be sure to include the relevant information so that the bug can be reproduced: the version of pugixml, compiler version and target architecture, the code that uses pugixml and exhibits the bug, etc.

-

-Feature requests can be reported the same way as bugs, so if you're missing some functionality in pugixml or if the API is rough in some places and you can suggest an improvement, file an issue. However please note that there are many factors when considering API changes (compatibility with previous versions, API redundancy, etc.), so generally features that can be implemented via a small function without pugixml modification are not accepted. However, all rules have exceptions.

-

-If you have a contribution to pugixml, such as build script for some build system/IDE, or a well-designed set of helper functions, or a binding to some language other than C++, please file an issue. You can include the relevant patches as issue attachments. Your contribution has to be distributed under the terms of a license that's compatible with pugixml license; i.e. GPL/LGPL licensed code is not accepted.

-

-[#email]

-If filing an issue is not possible due to privacy or other concerns, you can contact pugixml author by e-mail directly: [@mailto:arseny.kapoulkine@gmail.com arseny.kapoulkine@gmail.com].

-

-[endsect] [/feedback]

-

-[section:changelog Changelog]

-

-Only changes since version 0.5 are listed here; you can [@changes.txt view the full changelog here].

- 

-Version 0.9:

-

-* Major Unicode improvements:

-	# Introduced encoding support (automatic/manual encoding detection on load, manual encoding selection on save, conversion from/to UTF8, UTF16 LE/BE, UTF32 LE/BE) 

-	# Introduced wchar_t mode (you can set PUGIXML_WCHAR_MODE define to switch pugixml internal encoding from UTF8 to wchar_t; all functions are switched to their Unicode variants) 

-	# Load/save functions now support wide streams

-

-* Bug fixes:

-	# Fixed document corruption on failed parsing bug 

-	# XPath string <-> number conversion improvements (increased precision, fixed crash for huge numbers) 

-	# Improved DOCTYPE parsing: now parser recognizes all well-formed DOCTYPE declarations 

-	# Fixed xml_attribute::as_uint() for large numbers (i.e. 2^32-1)

-

-* Specification changes:

-	# parse() API changed to load_buffer/load_buffer_inplace/load_buffer_inplace_own; load_buffer APIs do not require zero-terminated strings. 

-	# Renamed as_utf16 to as_wide 

-	# Changed xml_node::offset_debug return type and xml_parse_result::offset type to ptrdiff_t 

-	# Nodes/attributes with empty names are now printed as :anonymous

-

-* Performance improvements:

-	# Optimized document parsing and saving 

-	# Changed internal memory management: internal allocator is used for both metadata and name/value data; allocated pages are deleted if all allocations from them are deleted 

-	# Optimized memory consumption: sizeof(xml_node_struct) reduced from 40 bytes to 32 bytes on x86 

-	# Optimized debug mode parsing/saving by order of magnitude

-

-* Miscellaneous:

-	# All STL includes except <exception> in pugixml.hpp are replaced with forward declarations

-

-* Compatibility:

-	# parse() and as_utf16 are left for compatibility (these functions are deprecated and will be removed in pugixml-1.0) 

-	# Wildcard functions, document_order/precompute_document_order functions, format_write_bom_utf8 and parse_wnorm_attribute flags are deprecated and will be removed in version 1.0 

-

-[endsect] [/changelog]

-

-[section:thanks Acknowledgments]

-

-pugixml could not be developed without the help from many people; some of them are listed in this section. If you've played a part in pugixml development and you can not find yourself on this list, I'm truly sorry; please [link email send me an e-mail] so I can fix this.

-

-Thanks to *Kristen Wegner* for pugxml parser, which was used as a basis for pugixml.

-

-Thanks to *Neville Franks* for contributions to pugxml parser.

-

-Thanks to *Artyom Palvelev* for suggesting a lazy gap contraction approach.

-

-Thanks to *Vyacheslav Egorov* for documentation proofreading.

-

-[endsect] [/thanks]

-

-[section:license License]

-

-The pugixml library is distributed under the MIT license:

-

-[pre

-Copyright (c) 2006-2010 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.

+[endsect] [/install]

 

-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.

-]

-

-[endsect] [/license]

-

-[endsect] [/overview]

- 

 [section:dom Document object model]

 

 pugixml stores XML data in DOM-like way: the entire XML document (both document structure and element data) is stored in memory as a tree. The tree can be loaded from character stream (file, string, C++ I/O stream), then traversed via special API or XPath expressions. The whole tree is mutable: both node structure and node/attribute data can be changed at any time. Finally, the result of document transformations can be saved to a character stream (file, C++ I/O stream or custom transport).

@@ -337,7 +341,7 @@ The tree nodes can be of one of the following types (which together form the enu
 

 [:Here the node has name `"xml"` and a single attribute with name `"version"` and value `"1.0"`. By default declaration nodes are treated as non-essential part of XML markup and are not loaded during XML parsing. You can override this behavior by adding `parse_declaration` flag. Also, by default a dummy declaration is output when XML document is saved unless there is already a declaration in the document; you can disable this by adding `format_no_declaration` flag.]

 

-Finally, here is a complete example of XML document and the corresponding tree representation:

+Finally, here is a complete example of XML document and the corresponding tree representation ([@samples/tree.xml]):

 

 [table

 

@@ -369,9 +373,9 @@ Finally, here is a complete example of XML document and the corresponding tree r
 

 Despite the fact that there are several node types, there are only three C++ types representing the tree (`xml_document`, `xml_node`, `xml_attribute`); some operations on `xml_node` are only valid for certain node types. They are described below.

 

-`xml_document` is the owner of the entire document structure; it is a non-copyable class. The interface of `xml_document` consists of parsing functions (see ^3. Parsing^), saving functions (see ^4. Saving^) and the interface of `xml_node`, which allows for document inspection and/or modification. Note that while `xml_document` is a sub-class of `xml_node`, `xml_node` is not a polymorphic type; the inheritance is only used to simplify usage.

+`xml_document` is the owner of the entire document structure; it is a non-copyable class. The interface of `xml_document` consists of loading functions (see [link manual.loading]), saving functions (see [link manual.saving]) and the interface of `xml_node`, which allows for document inspection and/or modification. Note that while `xml_document` is a sub-class of `xml_node`, `xml_node` is not a polymorphic type; the inheritance is only used to simplify usage.

 

-Default constructor of `xml_document` initializes the document to the tree with only a root node (document node). You can then populate it with data using either tree modification functions or parsing functions; all parsing functions destroy the previous tree with all occupied memory, which puts existing nodes/attributes from this document to invalid state. Destructor of `xml_document` also destroys the tree, thus the lifetime of the document object should exceed the lifetimes of any node/attribute handles that point to the tree.

+Default constructor of `xml_document` initializes the document to the tree with only a root node (document node). You can then populate it with data using either tree modification functions or loading functions; all loading functions destroy the previous tree with all occupied memory, which puts existing nodes/attributes from this document to invalid state. Destructor of `xml_document` also destroys the tree, thus the lifetime of the document object should exceed the lifetimes of any node/attribute handles that point to the tree.

 

 [caution While technically node/attribute handles can be alive when the tree they're referring to is destroyed, calling any member function of these handles results in undefined behavior. Thus it is recommended to make sure that the document is destroyed only after all references to its nodes/attributes are destroyed.]

 

@@ -381,9 +385,10 @@ There is a special value of `xml_node` type, known as null node or empty node. I
 

 `xml_attribute` is the handle to a XML attribute; it has the same semantics as `xml_node`, i.e. there can be several `xml_attribute` handles pointing to the same underlying object, there is a special null attribute value, which propagates to function results.

 

-You can check if a given `xml_node`/`xml_attribute` handle is null by calling the following method:

+You can check if a given `xml_node`/`xml_attribute` handle is null by calling the following methods:

 

-	bool empty() const;

+	bool xml_node::empty() const;

+	bool xml_attribute::empty() const;

 

 Nodes and attributes do not exist outside of document tree, so you can't create them without adding them to some document. Once underlying node/attribute objects are destroyed, the handles to those objects become invalid. While this means that destruction of the entire tree invalidates all node/attribute handles, it also means that destroying a subtree (by calling `remove_child`) or removing an attribute invalidates the corresponding handles. There is no way to check handle validity; you have to ensure correctness through external mechanisms.

 

@@ -393,23 +398,23 @@ Both `xml_node` and `xml_attribute` have the default constructor which initializ
 

 [section:unicode Unicode interface]

 

-There are two choices of interface and internal representation when configuring pugixml: you can either choose the UTF-8 (also called char) interface or UTF-16/32 (also called wchar_t) one. The choice is controlled via `PUGIXML_WCHAR_MODE` define; you can set it via [file pugiconfig.hpp] or via preprocessor options, as discussed in [link manual.overview.building.config]. If this define is set, the wchar_t interface is used; otherwise (by default) the char interface is used. The exact wide character encoding is assumed to be either UTF-16 or UTF-32 and is determined based on size of `wchar_t` type.

+There are two choices of interface and internal representation when configuring pugixml: you can either choose the UTF-8 (also called char) interface or UTF-16/32 (also called wchar_t) one. The choice is controlled via `PUGIXML_WCHAR_MODE` define; you can set it via [file pugiconfig.hpp] or via preprocessor options, as discussed in [link manual.install.building.config]. If this define is set, the wchar_t interface is used; otherwise (by default) the char interface is used. The exact wide character encoding is assumed to be either UTF-16 or UTF-32 and is determined based on size of `wchar_t` type.

 

 [note If size of `wchar_t` is 2, pugixml assumes UTF-16 encoding instead of UCS-2, which means that some characters are represented as two code points.]

 

 All tree functions that work with strings work with either C-style null terminated strings or STL strings of the selected character type. For example, node name accessors look like this in char mode:

 

-	const char* name() const;

-	bool set_name(const char* value);

+	const char* xml_node::name() const;

+	bool xml_node::set_name(const char* value);

 

 and like this in wchar_t mode:

 

-	const wchar_t* name() const;

-	bool set_name(const wchar_t* value);

+	const wchar_t* xml_node::name() const;

+	bool xml_node::set_name(const wchar_t* value);

 

 There is a special type, `pugi::char_t`, that is defined as the character type and depends on the library configuration; it will be also used in the documentation hereafter. There is also a type `pugi::string_t`, which is defined as the STL string of the character type; it corresponds to `std::string` in char mode and to `std::wstring` in wchar_t mode.

 

-In addition to the interface, the internal implementation changes to store XML data as `pugi::char_t`; this means that these two modes have different memory usage characteristics. The conversion to `pugi::char_t` upon document parsing and from `pugi::char_t` upon document saving happen automatically, which also carries minor performance penalty. The general advice however is to select the character mode based on usage scenario, i.e. if UTF-8 is inconvenient to process and most of your XML data is localized, wchar_t mode is probably a better choice.

+In addition to the interface, the internal implementation changes to store XML data as `pugi::char_t`; this means that these two modes have different memory usage characteristics. The conversion to `pugi::char_t` upon document loading and from `pugi::char_t` upon document saving happen automatically, which also carries minor performance penalty. The general advice however is to select the character mode based on usage scenario, i.e. if UTF-8 is inconvenient to process and most of your XML data is localized, wchar_t mode is probably a better choice.

 

 There are cases when you'll have to convert string data between UTF-8 and wchar_t encodings; the following helper functions are provided for such purposes:

 

@@ -417,6 +422,14 @@ There are cases when you'll have to convert string data between UTF-8 and wchar_
 	std::wstring as_wide(const char* str);

 

 Both functions accept null-terminated string as an argument `str`, and return the converted string. `as_utf8` performs conversion from UTF-16/32 to UTF-8; `as_wide` performs conversion from UTF-8 to UTF-16/32. Invalid UTF sequences are silently discarded upon conversion. `str` has to be a valid string; passing null pointer results in undefined behavior.

+

+[note Most examples in this documentation assume char interface and therefore will not compile with `PUGIXML_WCHAR_MODE`. This is to simplify the documentation; usually the only changes you'll have to make is to pass `wchar_t` string literals, i.e. instead of

+

+`pugi::xml_node node = doc.child("bookstore").find_child_by_attribute("book", "id", "12345");`

+

+you'll have to do

+

+`pugi::xml_node node = doc.child(L"bookstore").find_child_by_attribute(L"book", L"id", L"12345");`]

  

 [endsect] [/unicode]

 

@@ -463,7 +476,7 @@ You can use the following accessor functions to change or get current memory man
 

 Allocation function is called with the size (in bytes) as an argument and should return a pointer to memory block with alignment that is suitable for pointer storage and size that is greater or equal to the requested one. If the allocation fails, the function has to return null pointer (throwing an exception from allocation function results in undefined behavior). Deallocation function is called with the pointer that was returned by the previous call or with a null pointer; null pointer deallocation should be handled as a no-op. If memory management functions are not thread-safe, library thread safety is not guaranteed.

 

-This is a simple example of custom memory management ([@samples/custom_memory_management.cpp])

+This is a simple example of custom memory management ([@samples/custom_memory_management.cpp]):

 

 [import samples/custom_memory_management.cpp]

 [code_custom_memory_management_decl]

@@ -479,7 +492,7 @@ When setting new memory management functions, care must be taken to make sure th
 

 Constructing a document object using the default constructor does not result in any allocations; document node is stored inside the `xml_document` object.

 

-When the document is loaded from file/buffer, unless an inplace loading function is used (see ^3. Parsing^), a complete copy of character stream is made; all names/values of nodes and attributes are allocated in this buffer. This buffer is allocated via a single large allocation and is only freed when document memory is reclaimed (i.e. if the `xml_document` object is destroyed or if another document is loaded in the same object). Also when loading from file or stream, an additional large allocation may be performed if encoding conversion is required; a temporary buffer is allocated, and it is freed before load function returns.

+When the document is loaded from file/buffer, unless an inplace loading function is used (see [link manual.loading.memory]), a complete copy of character stream is made; all names/values of nodes and attributes are allocated in this buffer. This buffer is allocated via a single large allocation and is only freed when document memory is reclaimed (i.e. if the `xml_document` object is destroyed or if another document is loaded in the same object). Also when loading from file or stream, an additional large allocation may be performed if encoding conversion is required; a temporary buffer is allocated, and it is freed before load function returns.

 

 All additional memory, such as memory for document structure (node/attribute objects) and memory for node/attribute names/values is allocated in pages on the order of 32 kilobytes; actual objects are allocated inside the pages using a memory management scheme optimized for fast allocation/deallocation of many small objects. Because of the scheme specifics, the pages are only destroyed if all objects inside them are destroyed; also, generally destroying an object does not mean that subsequent object creation will reuse the same memory. This means that it is possible to devise a usage scheme which will lead to higher memory usage than expected; one example is adding a lot of nodes, and them removing all even numbered ones; not a single page is reclaimed in the process. However this is an example specifically crafted to produce unsatisfying behavior; in all practical usage scenarios the memory consumption is less than that of a general-purpose allocator because allocation meta-data is very small in size.

 

@@ -489,7 +502,57 @@ All additional memory, such as memory for document structure (node/attribute obj
 

 [endsect] [/dom]

 

-3. Parsing document (+ error handling!) (+ W3C conformance)

+[section:loading Loading document]

+

+pugixml provides several functions for loading XML data from various places - files, C++ iostreams, memory buffers. All functions use an extremely fast non-validating parser. This parser is not fully W3C conformant - it can load any valid XML document, but does not perform some well-formedness checks. While considerable effort is made to reject invalid XML documents, some validation is not performed because of performance reasons. Also some XML transformations (i.e. EOL handling or attribute value normalization) can impact parsing speed and thus can be disabled. However for vast majority of XML documents there is no performance difference between different parsing options. Parsing options also control whether certain XML nodes are parsed; see [link manual.loading.options] for more information.

+

+XML data is always converted to internal character format (see [link manual.dom.unicode]) before parsing. pugixml supports all popular Unicode encodings (UTF-8, UTF-16 (big and little endian), UTF-32 (big and little endian); UCS-2 is naturally supported since its a strict subset of UTF-16) and handles all encoding conversions automatically. Unless explicit encoding is specified, loading functions perform automatic encoding detection based on first few characters of XML data, so in almost all cases you do not have to specify document encoding. Encoding conversion is described in more detail in [link manual.loading.encoding].

+

+[section:file Loading document from file]

+

+The most common source of XML data is files; pugixml provides a separate function for loading XML document from file:

+

+	xml_parse_result xml_document::load_file(const char* path, unsigned int options = parse_default, encoding_t encoding = encoding_auto);

+	

+This function accepts file path as its first argument, and also two optional arguments, which specify parsing options (see [link manual.loading.options]) and input data encoding (see [link manual.loading.encoding]). The path has the target operating system format, so it can be a relative or absolute one, it should have the delimiters of target system, it should have the exact case if target file system is case-sensitive, etc. File path is passed to file opening function as-is without any modifications.

+

+`load_file` returns the result of the operation in a `xml_parse_result` object; this object contains the operation status, and the related information (i.e. last successfully parsed position in the input file, if parsing fails). See [link manual.loading.errors] for error handling details.

+

+[note As of version 0.9, there is no function for loading XML document from wide character path. Unfortunately, there is no portable way to do this; the version 1.0 will provide such function only for platforms with the corresponding functionality. You can use stream-loading functions as a workaround if your STL implementation can open file streams via `wchar_t` paths.]

+

+This is a simple example of loading XML document from file ([@samples/load_file.cpp]):

+

+[import samples/load_file.cpp]

+[code_load_file]

+

+[endsect] [/file]

+

+[section:memory Loading document from memory]

+foo

+[endsect] [/memory]

+

+[section:stream Loading document from C++ IO streams]

+foo

+[endsect] [/stream]

+

+[section:errors Handling parsing errors]

+foo

+concise syntax (if (!doc.load(...)) ...)

+[endsect] [/errors]

+

+[section:options Parsing options]

+foo

+[endsect] [/options]

+

+[section:encoding Encodings]

+foo

+[endsect] [/encoding]

+

+[section:w3c W3C specification conformance]

+foo

+[endsect] [/w3c]

+

+[endsect] [/loading]

 

 4. Getting data from document