ZIP and BASE64 Handling
[DLL]

All TFORMer functions accepting filenames may also be called with a name of a ZIP-file or with a BASE64 encoded string (which may contain a zip-file again). More...

Collaboration diagram for ZIP and BASE64 Handling:

Functions
TECIT_DLLSPEC HTUNZIPPER	TecUnzipper_Alloc (LPCSTR pszFilename)
	Allocated memory for a new unzipper handle.
TECIT_DLLSPEC HTUNZIPPER	TecUnzipper_AllocW (LPCWSTR pszFilename)
	Allocated memory for a new unzipper handle.
TECIT_DLLSPEC VOID	TecUnzipper_Free (HTUNZIPPER htUnzipper)
	Deallocates memory allocated by TecUnzipper_Alloc.
TECIT_DLLSPEC ERRCODE	TecUnzipper_DeleteAllFiles (HTUNZIPPER htUnzipper)
	Deletes all files and directories on disk that have been created by TecUnzipper_Extract.
TECIT_DLLSPEC ERRCODE	TecUnzipper_Base64Decode (HTUNZIPPER htUnzipper)
	Tests if the passed to TecUnzipper_Alloc is a BASE64 encoded string and decodes it to a temporary file.
TECIT_DLLSPEC ERRCODE	TecUnzipper_Extract (HTUNZIPPER htUnzipper, LPCSTR pszDirectory)
	Extracts a ZIP file into a temporary directory.
TECIT_DLLSPEC ERRCODE	TecUnzipper_ExtractW (HTUNZIPPER htUnzipper, LPCWSTR pszDirectory)
	Extracts a ZIP file into a temporary directory.
TECIT_DLLSPEC INT	TecUnzipper_GetFileCount (HTUNZIPPER htUnzipper)
	Returns the number of files that have been extracted.
TECIT_DLLSPEC LPCSTR	TecUnzipper_GetFile (HTUNZIPPER htUnzipper, INT nIndex)
	Returns the filename with the specified index (0.
TECIT_DLLSPEC INT	TecUnzipper_FindFileByExt (HTUNZIPPER htUnzipper, LPCSTR pszExtension, INT nStartIndex, BOOL bCaseInsensitiveSearch)
	Finds the first file in the set of extracted files that matches the specified file extension.
TECIT_DLLSPEC INT	TecUnzipper_FindFileByExtW (HTUNZIPPER htUnzipper, LPCWSTR pszExtension, INT nStartIndex, BOOL bCaseInsensitiveSearch)
	Finds the first file in the set of extracted files that matches the specified file extension.
TECIT_DLLSPEC LPSTR	TecUnzipper_Base64_Encode (LPCSTR szData, LONG lLen)
	Creates a BASE64 encoded string.
TECIT_DLLSPEC VOID	TecUnzipper_Base64_Free (LPSTR szStr)
	Free a BASE64 encoded string created with TecUnzipper_Base64_Encode.
TECIT_DLLSPEC LPCSTR	TecUnzipper_GetFilename (HTUNZIPPER htUnzipper)
	Returns the filename of the zip file being used or of the temp file created by TecUnzipper_Base64Decode.

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Detailed Description

All TFORMer functions accepting filenames may also be called with a name of a ZIP-file or with a BASE64 encoded string (which may contain a zip-file again).

Functions in this group enable the software developer to implement an optimized handling of such zip-files (or BASE64 string).

Usually all TFORMer functions accepting files are trying to determine if it is a zip-file automatically (a BASE64 encoded file is determined by the BASE64: prefix). When TFORMer detects a zip-file it is unzipped automatically to the temp-directory of the current user. This automatic unzipping requires TFORMer to clean up such temporary files after the function call ends. If you want to avoid the per-function unzipping and deleting, then implement the unzipping functionality yourself by the TecUnzipper-functions. Thereafter pass the resulting files to the TFORMer functions.

• Some declarations

     ERRCODE eCode       = ErrOk;
     LPCSTR  pszFilename = "repository.zip";
  

• Allocate an unzipper handle

        HTUNZIPPER hZip = TecUnzipper_Alloc( pszFilename );
        if( !hZip )
          return ERROR_OUTOFMEMORY;
  

• Make sure that data is always BASE64 decoded. Not required in this case, but should be always done so that you can pass strings starting with "BASE64:" to TecUnzipper_Alloc

        TecUnzipper_Base64Decode( hZip );
  

• Extract data to a temporary directory

        eCode = TecUnzipper_Extract( hZip, NULL );
  

• Check the return code to see if extracting was successful

        if( eCode == ErrOk )
        {
  

• Find the first Repository in the zip file

          INT nIndex  = TecUnzipper_FindFileByExt( hZip, "TFR", -1, TRUE );
          if( nIndex == -1 )
  

• The zip archive does not contain a TFORMer Repository file.

            eCode = ERROR_FILE_NOT_FOUND;
          else
  

• Get the absolute path to the extracted Repository file.

            pszFilename = TecUnzipper_GetFile( hZip, nIndex );
        }
        else
        {
  

• The passed filename was neither a zip file nor a base 64 encoded string. Ignore the error and work with the data as a normal TFR file.

          pszFilename = TecUnzipper_GetFilename( hZip );
          eCode       = ErrOk;
        }
  

• pszFilename contains now the path to a normal temporary TFR file
• Do something with pszFilename now ...
• Delete created temporary files

     TecUnzipper_DeleteAllFiles( hZip );
  

• Free the unzipper handle

        TecUnzipper_Free( hZip );