platformutils.hpp

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      * This must be implemented by the per-platform driver, which should
      * use local file services to open the passed file. If it fails, a
      * null handle pointer should be returned.
      *
      * @param fileName The string containing the name of the file
      *
      * @return The file handle of the opened file
      */
    static FileHandle openFile(const XMLCh* const fileName
        , MemoryManager* const manager  = XMLPlatformUtils::fgMemoryManager);

    /** Open a named file to write
      *
      * This must be implemented by the per-platform driver, which should
      * use local file services to open passed file. If it fails, a
      * null handle pointer should be returned.
      *
      * @param fileName The string containing the name of the file
      *
      * @return The file handle of the opened file
      */
    static FileHandle openFileToWrite(const char* const fileName
        , MemoryManager* const manager  = XMLPlatformUtils::fgMemoryManager);

    /** Open a named file to write
      *
      * This must be implemented by the per-platform driver, which should
      * use local file services to open the passed file. If it fails, a
      * null handle pointer should be returned.
      *
      * @param fileName The string containing the name of the file
      *
      * @return The file handle of the opened file
      */
    static FileHandle openFileToWrite(const XMLCh* const fileName
        , MemoryManager* const manager  = XMLPlatformUtils::fgMemoryManager);

    /** Opens the standard input as a file
      *
      * This must be implemented by the per-platform driver, which should
      * use local file services to open a handle to the standard input.
      * It should be a copy of the standard input handle, since it will
      * be closed later!
      *
      * @return The file handle of the standard input stream
      */
    static FileHandle openStdInHandle(MemoryManager* const manager  = XMLPlatformUtils::fgMemoryManager);

    /** Reads the file buffer
      *
      * This must be implemented by the per-platform driver, which should
      * use local file services to read up to 'toRead' bytes of data from
      * the passed file, and return those bytes in the 'toFill' buffer. It
      * is not an error not to read the requested number of bytes. When the
      * end of file is reached, zero should be returned.
      *
      * @param theFile The file handle to be read from.
      * @param toRead The maximum number of byte to read from the current
      * position
      * @param toFill The byte buffer to fill
      *
      * @return Returns the number of bytes read from the stream or file
      */
    static unsigned int readFileBuffer
    (
                FileHandle      theFile
        , const unsigned int    toRead
        ,       XMLByte* const  toFill
        , MemoryManager* const manager  = XMLPlatformUtils::fgMemoryManager
    );

    /** Writes the buffer to the file
      *
      * This must be implemented by the per-platform driver, which should
      * use local file services to write up to 'toWrite' bytes of data to
      * the passed file. Unless exception raised by local file services,
      * 'toWrite' bytes of data is to be written to the passed file.
      *
      * @param theFile The file handle to be written to.
      * @param toWrite The maximum number of byte to write from the current
      * position
      * @param toFlush The byte buffer to flush
      *
      * @return void
      */
    static void writeBufferToFile
    (
          FileHandle     const  theFile
        , long                  toWrite
        , const XMLByte* const  toFlush
        , MemoryManager* const manager  = XMLPlatformUtils::fgMemoryManager
    );

    /** Resets the file handle
      *
      * This must be implemented by the per-platform driver which will use
      * local file services to reset the file position to the start of the
      * the file.
      *
      * @param theFile The file handle that you want to reset
      */
    static void resetFile(FileHandle theFile
        , MemoryManager* const manager  = XMLPlatformUtils::fgMemoryManager);

    //@}


    /** @name File System Methods */
    //@{
    /** Gets the full path from a relative path
      *
      * This must be implemented by the per-platform driver. It should
      * complete a relative path using the 'current directory', or whatever
      * the local equivalent of a current directory is. If the passed
      * source path is actually fully qualified, then a straight copy of it
      * will be returned.
      *
      * @param srcPath The path of the file for which you want the full path
      *
      * @param manager Pointer to the memory manager to be used to
      *                allocate objects.
      *
      * @return Returns the fully qualified path of the file name including
      *         the file name. This is dyanmically allocated and must be
      *         deleted  by the caller when its no longer needed! The memory
      *         returned will beallocated using the static memory manager, if
      *         user do not supply a memory manager. Users then need to make
      *         sure to use either the default or user specific memory manager
      *         to deallocate the memory.
      */
    static XMLCh* getFullPath
    (
        const XMLCh* const srcPath
        , MemoryManager* const manager = XMLPlatformUtils::fgMemoryManager
    );

    /** Gets the current working directory 
      *
      * This must be implemented by the per-platform driver. It returns 
      * the current working directory is. 
      *
      * @return Returns the current working directory. 
      *         This is dyanmically allocated and must be deleted
      *         by the caller when its no longer needed! The memory returned
      *         will be allocated using the static memory manager, if users
      *         do not supply a memory manager. Users then need to make sure
      *         to use either the default or user specific memory manager to
      *         deallocate the memory.
      */
    static XMLCh* getCurrentDirectory
    (
        MemoryManager* const manager = XMLPlatformUtils::fgMemoryManager
    );

    /** Check if a charater is a slash
      *
      * This must be implemented by the per-platform driver. 
      *
      * @param c the character to be examined
      *
      * @return true  if the character examined is a slash
      *         false otherwise
      */
    static inline bool isAnySlash(XMLCh c);
    
    /** Remove occurences of the pair of dot slash 
      *
      * To remove the sequence, dot slash if it is part of the sequence,
      * slash dot slash.
      *
      * @param srcPath The path for which you want to remove the dot slash sequence.
      *
      * @return 
      */
    static void   removeDotSlash(XMLCh* const srcPath
        , MemoryManager* const manager = XMLPlatformUtils::fgMemoryManager);

    /** Remove occurences of the dot dot slash 
      *
      * To remove the sequence, slash dot dot slash and its preceding path segment
      * if and only if the preceding path segment is not slash dot dot slash.
      *
      * @param srcPath The path for which you want to remove the slash dot
      *        dot slash sequence and its preceding path segment.
      *
      * @return 
      */
    static void   removeDotDotSlash(XMLCh* const srcPath
        , MemoryManager* const manager = XMLPlatformUtils::fgMemoryManager);

    /** Determines if a path is relative or absolute
      *
      * This must be implemented by the per-platform driver, which should
      * determine whether the passed path is relative or not. The concept
      * of relative and absolute might be... well relative on different
      * platforms. But, as long as the determination is made consistently
      * and in coordination with the weavePaths() method, it should work
      * for any platform.
      *
      * @param toCheck The file name which you want to check
      *
      * @return Returns true if the filename appears to be relative
      */
    static bool isRelative(const XMLCh* const toCheck
        , MemoryManager* const manager = XMLPlatformUtils::fgMemoryManager
        );

    /** Utility to join two paths
      *
      * This must be implemented by the per-platform driver, and should
      * weave the relative path part together with the base part and return
      * a new path that represents this combination.
      *
      * If the relative part turns out to be fully qualified, it will be
      * returned as is. If it is not, then it will be woven onto the
      * passed base path, by removing one path component for each leading
      * "../" (or whatever is the equivalent in the local system) in the
      * relative path.
      *
      * @param basePath The string containing the base path
      * @param relativePath The string containing the relative path
      *
      * @return Returns a string containing the 'woven' path. It should
      * be dynamically allocated and becomes the responsibility of the
      * caller to delete.
      */
    static XMLCh* weavePaths
    (
        const   XMLCh* const    basePath
        , const XMLCh* const    relativePath
        , MemoryManager* const manager = XMLPlatformUtils::fgMemoryManager
    );
    //@}

    /** @name Timing Methods */
    //@{

    /** Gets the system time in milliseconds
      *
      * This must be implemented by the per-platform driver, which should
      * use local services to return the current value of a running
      * millisecond timer. Note that the value returned is only as accurate
      * as the millisecond time of the underyling host system.
      *
      * @return Returns the system time as an unsigned long
      */
    static unsigned long getCurrentMillis();
    //@}

    /** @name Mutex Methods */
    //@{

    /** Closes a mutex handle
      *
      * Each per-platform driver must implement this. Only it knows what
      * the actual content of the passed mutex handle is.
      *
      * @param mtxHandle The mutex handle that you want to close
      */
    static void closeMutex(void* const mtxHandle);

    /** Locks a mutex handle
      *
      * Each per-platform driver must implement this. Only it knows what
      * the actual content of the passed mutex handle is.
      *
      * @param mtxHandle The mutex handle that you want to lock
      */
    static void lockMutex(void* const mtxHandle);

    /** Make a new mutex
      *
      * Each per-platform driver must implement this. Only it knows what
      * the actual content of the passed mutex handle is. The returned
      * handle pointer will be eventually passed to closeMutex() which is
      * also implemented by the platform driver.
      */
    static void* makeMutex();

    /** Unlocks a mutex
      *
      * Each per-platform driver must implement this. Only it knows what
      * the actual content of the passed mutex handle is.
      *
      * Note that, since the underlying system synchronization services
      * are used, Xerces cannot guarantee that lock/unlock operations are
      * correctly enforced on a per-thread basis or that incorrect nesting
      * of lock/unlock operations will be caught.
      *
      * @param mtxHandle The mutex handle that you want to unlock
      */
    static void unlockMutex(void* const mtxHandle);

    //@}


    /** @name External Message Support */