// File: TXmlDocument.h // // Description: Here are a set of classes that deal with Xml files. None // of the classes throws exceptions. All errors are returned // as HRESULTS. All error values a listed below. // // These classes do a minimum of copying of data. When // reading the file, a view of it is mapped into memory. Then // all elements and attributes reference directly into the // mapping. So element and attribute names are NOT null // terminated. This is kind of a hassle for the user but // it eliminate the need for copies. // // When the Value is updated, a copy IS made. This way the // Xml SimpleTable implementer is not obligated to keep the // (often) temporary string variable around until the Save. // // Author: Stephen Rakonza (stephenr x63199) // // Date / Change: 9-15-1999 / Created // #ifndef __TXMLDOCUMENT_H__ #define __TXMLDOCUMENT_H__ #ifndef __SMARTPOINTER_H__ #include "SmartPointer.h" #endif #ifndef __TLIST_H__ #include "TList.h" #endif class TXmlAttribute; class TXmlDocument; class TXmlElement; class TXmlElementList; class TXmlNode; #ifndef ASSERT #define ASSERT(x) #endif //Error codes //E_OUTOFMEMORY #define E_NODENOTFOUND 0x80000001 #define E_ERROR_PARSING_XML 0x80000002 #define E_ATTRIBUTE_NOT_FOUND 0x80000003 #define E_ERROR_OPENING_FILE 0x80000004 // TFileMapping // // This class is the base class for Attributes and Elements. class TFileMapping { public: TFileMapping() : m_hFile(0), m_hMapping(0), m_pMapping(0), m_Size(0) {} ~TFileMapping() { if(m_pMapping) { if(0 == FlushViewOfFile(m_pMapping,0)) { ASSERT(false && "ERROR - UNABLE TO FLUSH TO DISK"); } UnmapViewOfFile(m_pMapping); } if(m_hMapping) CloseHandle(m_hMapping); if(m_hFile) CloseHandle(m_hFile); } HRESULT Load(LPCTSTR filename, bool bReadWrite = false) { //We don't do any error checking because the API functions should deal with NULL hFile & hMapping. Use should check //m_pMapping (via Mapping()) before using the object. m_hFile = CreateFile(filename, GENERIC_READ | (bReadWrite ? GENERIC_WRITE : 0), 0, NULL, OPEN_EXISTING, FILE_FLAG_RANDOM_ACCESS, NULL); m_hMapping = CreateFileMapping(m_hFile, NULL, (bReadWrite ? PAGE_READWRITE : PAGE_READONLY), 0, 0, NULL); m_pMapping = reinterpret_cast(MapViewOfFile(m_hMapping, (bReadWrite ? FILE_MAP_WRITE : FILE_MAP_READ), 0, 0, 0)); m_Size = GetFileSize(m_hFile, 0); return (0 == m_pMapping) ? E_ERROR_OPENING_FILE : S_OK; } unsigned long Size() const {return m_Size;} char * Mapping() const {return m_pMapping;} char * EOF() const {return (m_pMapping + m_Size);} private: HANDLE m_hFile; HANDLE m_hMapping; char * m_pMapping; unsigned long m_Size; }; // TXmlNode // // This class is the base class for Attributes and Elements. class TXmlNode { public: TXmlNode(); virtual ~TXmlNode(); void GetName(LPCSTR &o_pNodeName, size_t &o_cStringLengthName) const;//Length is returned because pNodeName is NOT necessarily NULL terminated. void GetValue(LPCSTR &o_pNodeValue, size_t &o_cStringLengthValue) const;//Length is returned because pNodeName is NOT necessarily NULL terminated. //The name is stored as a pointer only. This is because the Xml SimpleTable presumably //gets the Meta and stores the element and attribute names as memeber variables. So they //should be around for the life time of the XmlDocument object. void SetValue(LPCSTR i_szNodeValue); //This one makes a copy of the data public: enum Change { eUnchanged, eModify, eInsert, eRemove }; Change m_change; size_t m_cStringLengthName; size_t m_cStringLengthValue; TFileMapping * m_pMap; //Pointer to the whole document. Needed for checking begin and end of file. If 0 then Node is not attached to a Doc. LPCSTR m_pNodeName; //Here we store the pointer directly LPCSTR m_pNodeValue; //Here we store the pointer directly LPCSTR m_szUpdatedName; //Here's where we store the updated name pointer TSmartPointerArray m_szUpdatedValue; //Here's where we store a copy of the updated value LPCSTR AdvancePastWhitespaces(LPCSTR i_pString); void SetName(LPCSTR i_szNodeName); //This stores the pointer and does NOT make a copy of the string void SetName(LPCSTR i_pNodeName, LPCSTR i_szStringEndToken);//Use this one if you want SetName to search for then end token to determine //the length of the name. void SetValue(LPCSTR i_pNodeValue, LPCSTR i_szStringEndToken); }; // TXmlAttribute // // This class represents a singe Attribute class TXmlAttribute : public TXmlNode { public: TXmlAttribute() : m_bSingleQuotes(false){} bool IsUsingSingleQuote() const {return m_bSingleQuotes;} void UseSingleQuote(bool bSingeQuote=true){m_bSingleQuotes = bSingeQuote;} //XmlDocument methods public: TXmlAttribute(LPCSTR i_pLeadingSpace, TFileMapping &i_pMap) : m_bSingleQuotes(false){} HRESULT Init(LPCSTR i_pLeadingSpace, TFileMapping *i_pMap); bool m_bSingleQuotes; //false indicates double quotes //Whitespace management LPCSTR m_pNodeBeginning; //This is a pointer to where the node starts (this is the first whitespace following the element name or preceeding attribute. LPCSTR m_pNodeEnd; //This is a pointer to where the node ends (pointer just past the quote) If the node is marked as Changed, then this is the //range of bytes that is replaced. }; // TXmlElement // // This class represents a singe Element class TXmlElement : public TXmlNode { //Consumer methods public: //Attribute Methods HRESULT GetAttributeValue(LPCSTR i_szName, LPCSTR &o_pValue, size_t &o_StringLength); HRESULT SetAttributeValue(LPCSTR i_szName, LPCSTR i_szValue); //Child Element Methods HRESULT GetChildList(TList *&o_XmlElementList); HRESULT InsertAsLastChild(TXmlElement &i_XmlElement); //This Element Methods void SetValue(LPCSTR i_szValue); //This sets the bEndingTag flag and calls the base class //XmlDocument methods public: TXmlElement(); TXmlElement(LPCSTR i_pOpenBracket); HRESULT Init(LPCSTR i_pOpenBracket, TFileMapping *i_pMap); private: TList m_AttributeList; //This is filled in when the first Attribute method is called bool m_bAttributeListInited; bool m_bChildListInited; bool m_bEndingTag; //This is set at ctor time. Or it can be set to true at SetValue or InsertAsLastChild time. TList m_ChildList; //This is filled in when the first Child Element method is called. //Whitespace management LPCSTR m_pNodeBeginning; //This is a pointer to where the node starts (the first white space following the previous nodes' '>') LPCSTR m_pNodeEnd; //This is a pointer to where the node ends (pointer just past the '>') If the node is marked as Changed, //then this is the range of bytes that is replaced. TXmlAttribute * GetAttribute(LPCSTR i_pName, size_t i_cbName); HRESULT PopulateAttributeList(); }; //Handling TXmlElement pointer - In order to reduce the number of copies, the consumer of pointer should delete the //pointer UNLESS changes are made. If changes are made to an XmlElement, it goes into the write cache and will be //cleaned up either at Save time or upon deletion of the XmlDocument. class TXmlDocument { public: TXmlDocument() {} ~TXmlDocument() {} HRESULT CreateElement(LPCSTR i_szElementName, TXmlElement *&o_pElement);//Creates a new element but does NOT put it into the XmlDocument //GetElement is designed specifically to get a Table element from an XML file. It scans from the beginning of the document //in search of the tag name. If there is more than one element of this name, only the first one will be acknowledged. HRESULT DeleteElement(TXmlElement &i_pElement);//Removes the element HRESULT GetElementList(LPCSTR i_szElementName, TList *&o_pElementList);//Find the first matching element. Fails if the element is not found. void ReleaseElementList(TList * &i_pElementList);//Element is no longer used by the consumer. If no changes have been made to the Element //it will be deleted. HRESULT Load(LPCWSTR i_wszXMLFileName, bool bReadWrite=false);//Maps the file into memory HRESULT Parse(bool i_bValidate=false);//Check the file for well formity and validates against XML Schema if bValidate is true HRESULT Save();//Saves the xml file with all of the updates private: TFileMapping m_FileMapping; }; #endif // __TXMLDOCUMENT_H__