tinyxml.h

这个代码用C＋＋实现了一个小型虚拟机

	/// STL std::string form.	
	void SetValue( const std::string& _value )	
	{	
		StringToBuffer buf( _value );
		SetValue( buf.buffer ? buf.buffer : "error" );	
	}
	#endif

	/// Get the next sibling attribute in the DOM. Returns null at end.
	const TiXmlAttribute* Next() const;
	TiXmlAttribute* Next();
	/// Get the previous sibling attribute in the DOM. Returns null at beginning.
	const TiXmlAttribute* Previous() const;
	TiXmlAttribute* Previous();

	bool operator==( const TiXmlAttribute& rhs ) const { return rhs.name == name; }
	bool operator<( const TiXmlAttribute& rhs )	 const { return name < rhs.name; }
	bool operator>( const TiXmlAttribute& rhs )  const { return name > rhs.name; }

	/*	Attribute parsing starts: first letter of the name
						 returns: the next char after the value end quote
	*/
	virtual const char* Parse( const char* p, TiXmlParsingData* data, TiXmlEncoding encoding );

	// Prints this Attribute to a FILE stream.
	virtual void Print( FILE* cfile, int depth ) const;

	virtual void StreamOut( TIXML_OSTREAM * out ) const;
	// [internal use]
	// Set the document pointer so the attribute can report errors.
	void SetDocument( TiXmlDocument* doc )	{ document = doc; }

private:
	TiXmlAttribute( const TiXmlAttribute& );				// not implemented.
	void operator=( const TiXmlAttribute& base );	// not allowed.

	TiXmlDocument*	document;	// A pointer back to a document, for error reporting.
	TIXML_STRING name;
	TIXML_STRING value;
	TiXmlAttribute*	prev;
	TiXmlAttribute*	next;
};


/*	A class used to manage a group of attributes.
	It is only used internally, both by the ELEMENT and the DECLARATION.
	
	The set can be changed transparent to the Element and Declaration
	classes that use it, but NOT transparent to the Attribute
	which has to implement a next() and previous() method. Which makes
	it a bit problematic and prevents the use of STL.

	This version is implemented with circular lists because:
		- I like circular lists
		- it demonstrates some independence from the (typical) doubly linked list.
*/
class TiXmlAttributeSet
{
public:
	TiXmlAttributeSet();
	~TiXmlAttributeSet();

	void Add( TiXmlAttribute* attribute );
	void Remove( TiXmlAttribute* attribute );

	const TiXmlAttribute* First()	const	{ return ( sentinel.next == &sentinel ) ? 0 : sentinel.next; }
	TiXmlAttribute* First()					{ return ( sentinel.next == &sentinel ) ? 0 : sentinel.next; }
	const TiXmlAttribute* Last() const		{ return ( sentinel.prev == &sentinel ) ? 0 : sentinel.prev; }
	TiXmlAttribute* Last()					{ return ( sentinel.prev == &sentinel ) ? 0 : sentinel.prev; }

	const TiXmlAttribute*	Find( const char * name ) const;
	TiXmlAttribute*	Find( const char * name );

private:
	//*ME:	Because of hidden/disabled copy-construktor in TiXmlAttribute (sentinel-element),
	//*ME:	this class must be also use a hidden/disabled copy-constructor !!!
	TiXmlAttributeSet( const TiXmlAttributeSet& );	// not allowed
	void operator=( const TiXmlAttributeSet& );	// not allowed (as TiXmlAttribute)

	TiXmlAttribute sentinel;
};


/** The element is a container class. It has a value, the element name,
	and can contain other elements, text, comments, and unknowns.
	Elements also contain an arbitrary number of attributes.
*/
class TiXmlElement : public TiXmlNode
{
public:
	/// Construct an element.
	TiXmlElement (const char * in_value);

	#ifdef TIXML_USE_STL
	/// std::string constructor.
	TiXmlElement( const std::string& _value );
	#endif

	TiXmlElement( const TiXmlElement& );

	void operator=( const TiXmlElement& base );

	virtual ~TiXmlElement();

	/** Given an attribute name, Attribute() returns the value
		for the attribute of that name, or null if none exists.
	*/
	const char* Attribute( const char* name ) const;

	/** Given an attribute name, Attribute() returns the value
		for the attribute of that name, or null if none exists.
		If the attribute exists and can be converted to an integer,
		the integer value will be put in the return 'i', if 'i'
		is non-null.
	*/
	const char* Attribute( const char* name, int* i ) const;

	/** Given an attribute name, Attribute() returns the value
		for the attribute of that name, or null if none exists.
		If the attribute exists and can be converted to an double,
		the double value will be put in the return 'd', if 'd'
		is non-null.
	*/
	const char* Attribute( const char* name, double* d ) const;

	/** QueryIntAttribute examines the attribute - it is an alternative to the
		Attribute() method with richer error checking.
		If the attribute is an integer, it is stored in 'value' and 
		the call returns TIXML_SUCCESS. If it is not
		an integer, it returns TIXML_WRONG_TYPE. If the attribute
		does not exist, then TIXML_NO_ATTRIBUTE is returned.
	*/	
	int QueryIntAttribute( const char* name, int* _value ) const;
	/// QueryDoubleAttribute examines the attribute - see QueryIntAttribute().
	int QueryDoubleAttribute( const char* name, double* _value ) const;
	/// QueryFloatAttribute examines the attribute - see QueryIntAttribute().
	int QueryFloatAttribute( const char* name, float* _value ) const {
		double d;
		int result = QueryDoubleAttribute( name, &d );
		if ( result == TIXML_SUCCESS ) {
			*_value = (float)d;
		}
		return result;
	}

	/** Sets an attribute of name to a given value. The attribute
		will be created if it does not exist, or changed if it does.
	*/
	void SetAttribute( const char* name, const char * _value );

    #ifdef TIXML_USE_STL
	const char* Attribute( const std::string& name ) const				{ return Attribute( name.c_str() ); }
	const char* Attribute( const std::string& name, int* i ) const		{ return Attribute( name.c_str(), i ); }
	const char* Attribute( const std::string& name, double* d ) const	{ return Attribute( name.c_str(), d ); }
	int QueryIntAttribute( const std::string& name, int* _value ) const	{ return QueryIntAttribute( name.c_str(), _value ); }
	int QueryDoubleAttribute( const std::string& name, double* _value ) const { return QueryDoubleAttribute( name.c_str(), _value ); }

	/// STL std::string form.
	void SetAttribute( const std::string& name, const std::string& _value )	
	{	
		StringToBuffer n( name );
		StringToBuffer v( _value );
		if ( n.buffer && v.buffer )
			SetAttribute (n.buffer, v.buffer );	
	}	
	///< STL std::string form.
	void SetAttribute( const std::string& name, int _value )	
	{	
		StringToBuffer n( name );
		if ( n.buffer )
			SetAttribute (n.buffer, _value);	
	}	
	#endif

	/** Sets an attribute of name to a given value. The attribute
		will be created if it does not exist, or changed if it does.
	*/
	void SetAttribute( const char * name, int value );

	/** Sets an attribute of name to a given value. The attribute
		will be created if it does not exist, or changed if it does.
	*/
	void SetDoubleAttribute( const char * name, double value );

	/** Deletes an attribute with the given name.
	*/
	void RemoveAttribute( const char * name );
    #ifdef TIXML_USE_STL
	void RemoveAttribute( const std::string& name )	{	RemoveAttribute (name.c_str ());	}	///< STL std::string form.
	#endif

	const TiXmlAttribute* FirstAttribute() const	{ return attributeSet.First(); }		///< Access the first attribute in this element.
	TiXmlAttribute* FirstAttribute() 				{ return attributeSet.First(); }
	const TiXmlAttribute* LastAttribute()	const 	{ return attributeSet.Last(); }		///< Access the last attribute in this element.
	TiXmlAttribute* LastAttribute()					{ return attributeSet.Last(); }

	/** Convenience function for easy access to the text inside an element. Although easy
		and concise, GetText() is limited compared to getting the TiXmlText child
		and accessing it directly.
	
		If the first child of 'this' is a TiXmlText, the GetText()
		returns the character string of the Text node, else null is returned.

		This is a convenient method for getting the text of simple contained text:
		@verbatim
		<foo>This is text</foo>
		const char* str = fooElement->GetText();
		@endverbatim

		'str' will be a pointer to "This is text". 
		
		Note that this function can be misleading. If the element foo was created from
		this XML:
		@verbatim
		<foo><b>This is text</b></foo> 
		@endverbatim

		then the value of str would be null. The first child node isn't a text node, it is
		another element. From this XML:
		@verbatim
		<foo>This is <b>text</b></foo> 
		@endverbatim
		GetText() will return "This is ".

		WARNING: GetText() accesses a child node - don't become confused with the 
				 similarly named TiXmlHandle::Text() and TiXmlNode::ToText() which are 
				 safe type casts on the referenced node.
	*/
	const char* GetText() const;

	/// Creates a new Element and returns it - the returned element is a copy.
	virtual TiXmlNode* Clone() const;
	// Print the Element to a FILE stream.
	virtual void Print( FILE* cfile, int depth ) const;

	/*	Attribtue parsing starts: next char past '<'
						 returns: next char past '>'
	*/
	virtual const char* Parse( const char* p, TiXmlParsingData* data, TiXmlEncoding encoding );

protected:

	void CopyTo( TiXmlElement* target ) const;
	void ClearThis();	// like clear, but initializes 'this' object as well

	// Used to be public [internal use]
	#ifdef TIXML_USE_STL
	    virtual void StreamIn( TIXML_ISTREAM * in, TIXML_STRING * tag );
	#endif
	virtual void StreamOut( TIXML_OSTREAM * out ) const;

	/*	[internal use]
		Reads the "value" of the element -- another element, or text.
		This should terminate with the current end tag.
	*/
	const char* ReadValue( const char* in, TiXmlParsingData* prevData, TiXmlEncoding encoding );

private:

	TiXmlAttributeSet attributeSet;
};


/**	An XML comment.
*/
class TiXmlComment : public TiXmlNode
{
public:
	/// Constructs an empty comment.
	TiXmlComment() : TiXmlNode( TiXmlNode::COMMENT ) {}
	TiXmlComment( const TiXmlComment& );
	void operator=( const TiXmlComment& base );

	virtual ~TiXmlComment()	{}

	/// Returns a copy of this Comment.
	virtual TiXmlNode* Clone() const;
	/// Write this Comment to a FILE stream.
	virtual void Print( FILE* cfile, int depth ) const;

	/*	Attribtue parsing starts: at the ! of the !--
						 returns: next char past '>'
	*/
	virtual const char* Parse( const char* p, TiXmlParsingData* data, TiXmlEncoding encoding );

protected:
	void CopyTo( TiXmlComment* target ) const;

	// used to be public
	#ifdef TIXML_USE_STL
	    virtual void StreamIn( TIXML_ISTREAM * in, TIXML_STRING * tag );
	#endif
	virtual void StreamOut( TIXML_OSTREAM * out ) const;

private:

};


/** XML text. A text node can have 2 ways to output the next. "normal" output 
	and CDATA. It will default to the mode it was parsed from the XML file and
	you generally want to leave it alone, but you can change the output mode with 
	SetCDATA() and query it with CDATA().
*/
class TiXmlText : public TiXmlNode
{
	friend class TiXmlElement;
public:
	/** Constructor for text element. By default, it is treated as 
		normal, encoded text. If you want it be output as a CDATA text
		element, set the parameter _cdata to 'true'
	*/
	TiXmlText (const char * initValue ) : TiXmlNode (TiXmlNode::TEXT)
	{
		SetValue( initValue );
		cdata = false;
	}
	virtual ~TiXmlText() {}

	#ifdef TIXML_USE_STL
	/// Constructor.
	TiXmlText( const std::string& initValue ) : TiXmlNode (TiXmlNode::TEXT)
	{
		SetValue( initValue );
		cdata = false;
	}
	#endif

	TiXmlText( const TiXmlText& copy ) : TiXmlNode( TiXmlNode::TEXT )	{ copy.CopyTo( this ); }
	void operator=( const TiXmlText& base )							 	{ base.CopyTo( this ); }

	/// Write this text object to a FILE stream.
	virtual void Print( FILE* cfile, int depth ) const;

	/// Queries whether this represents text using a CDATA section.
	bool CDATA()					{ return cdata; }
	/// Turns on or off a CDATA representation of text.
	void SetCDATA( bool _cdata )	{ cdata = _cdata; }

	virtual const char* Parse( const char* p, TiXmlParsingData* data, TiXmlEncoding encoding );

protected :
	///  [internal use] Creates a new Element and returns it.
	virtual TiXmlNode* Clone() const;
	void CopyTo( TiXmlText* target ) const;

	virtual void StreamOut ( TIXML_OSTREAM * out ) const;
	bool Blank() const;	// returns true if all white space and new lines
	// [internal use]
	#ifdef TIXML_USE_STL
	    virtual void StreamIn( TIXML_ISTREAM * in, TIXML_STRING * tag );
	#endif

private:
	bool cdata;			// true if this should be input and output as a CDATA style text element
};


/** In correct XML the declaration is the first entry in the file.
	@verbatim
		<?xml version="1.0" standalone="yes"?>
	@endverbatim

	TinyXml will happily read or write files without a declaration,
	however. There are 3 possible attributes to the declaration:
	version, encoding, and standalone.

	Note: In this version of the code, the attributes are
	handled as special cases, not generic attributes, simply
	because there can only be at most 3 and they are always the same.
*/
class TiXmlDeclaration : public TiXmlNode
{
public:
	/// Construct an empty declaration.
	TiXmlDeclaration()   : TiXmlNode( TiXmlNode::DECLARATION ) {}

#ifdef TIXML_USE_STL