ftrfork.c

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                                        magic, result_offset );
  }


  static FT_Error
  raccess_guess_apple_single( FT_Library  library,
                              FT_Stream   stream,
                              char *      base_file_name,
                              char      **result_file_name,
                              FT_Long    *result_offset )
  {
    FT_Int32  magic = (0x00 << 24 | 0x05 << 16 | 0x16 << 8 | 0x00);


    *result_file_name = NULL;
    return raccess_guess_apple_generic( library, stream, base_file_name,
                                        magic, result_offset );
  }


  static FT_Error
  raccess_guess_darwin_ufs_export( FT_Library  library,
                                   FT_Stream   stream,
                                   char *      base_file_name,
                                   char      **result_file_name,
                                   FT_Long    *result_offset )
  {
    char*      newpath;
    FT_Error   error;
    FT_Memory  memory;

    FT_UNUSED( stream );


    memory  = library->memory;
    newpath = raccess_make_file_name( memory, base_file_name, "._" );
    if ( !newpath )
      return FT_Err_Out_Of_Memory;

    error = raccess_guess_linux_double_from_file_name( library, newpath,
                                                       result_offset );
    if ( !error )
      *result_file_name = newpath;
    else
      FT_FREE( newpath );

    return error;
  }


  static FT_Error
  raccess_guess_darwin_hfsplus( FT_Library  library,
                                FT_Stream   stream,
                                char *      base_file_name,
                                char      **result_file_name,
                                FT_Long    *result_offset )
  {
    /*
      Only meaningful on systems with hfs+ drivers (or Macs).
     */
    FT_Error   error;
    char*      newpath;
    FT_Memory  memory;
    FT_Long    base_file_len = ft_strlen( base_file_name );

    FT_UNUSED( stream );


    memory = library->memory;

    if ( base_file_len > FT_INT_MAX )
      return FT_Err_Array_Too_Large;

    if ( FT_ALLOC( newpath, base_file_len + 6 ) )
      return error;

    FT_MEM_COPY( newpath, base_file_name, base_file_len );
    FT_MEM_COPY( newpath + base_file_len, "/rsrc", 6 );

    *result_file_name = newpath;
    *result_offset    = 0;

    return FT_Err_Ok;
  }


  static FT_Error
  raccess_guess_vfat( FT_Library  library,
                      FT_Stream   stream,
                      char *      base_file_name,
                      char      **result_file_name,
                      FT_Long    *result_offset )
  {
    char*      newpath;
    FT_Memory  memory;

    FT_UNUSED( stream );


    memory = library->memory;

    newpath = raccess_make_file_name( memory, base_file_name,
                                      "resource.frk/" );
    if ( !newpath )
      return FT_Err_Out_Of_Memory;

    *result_file_name = newpath;
    *result_offset    = 0;

    return FT_Err_Ok;
  }


  static FT_Error
  raccess_guess_linux_cap( FT_Library  library,
                           FT_Stream   stream,
                           char *      base_file_name,
                           char      **result_file_name,
                           FT_Long    *result_offset )
  {
    char*      newpath;
    FT_Memory  memory;

    FT_UNUSED( stream );


    memory = library->memory;

    newpath = raccess_make_file_name( memory, base_file_name, ".resource/" );
    if ( !newpath )
      return FT_Err_Out_Of_Memory;

    *result_file_name = newpath;
    *result_offset    = 0;

    return FT_Err_Ok;
  }


  static FT_Error
  raccess_guess_linux_double( FT_Library  library,
                              FT_Stream   stream,
                              char *      base_file_name,
                              char      **result_file_name,
                              FT_Long    *result_offset )
  {
    char*      newpath;
    FT_Error   error;
    FT_Memory  memory;

    FT_UNUSED( stream );


    memory = library->memory;

    newpath = raccess_make_file_name( memory, base_file_name, "%" );
    if ( !newpath )
      return FT_Err_Out_Of_Memory;

    error = raccess_guess_linux_double_from_file_name( library, newpath,
                                                       result_offset );
    if ( !error )
      *result_file_name = newpath;
    else
      FT_FREE( newpath );

    return error;
  }


  static FT_Error
  raccess_guess_linux_netatalk( FT_Library  library,
                                FT_Stream   stream,
                                char *      base_file_name,
                                char      **result_file_name,
                                FT_Long    *result_offset )
  {
    char*      newpath;
    FT_Error   error;
    FT_Memory  memory;

    FT_UNUSED( stream );


    memory = library->memory;

    newpath = raccess_make_file_name( memory, base_file_name,
                                      ".AppleDouble/" );
    if ( !newpath )
      return FT_Err_Out_Of_Memory;

    error = raccess_guess_linux_double_from_file_name( library, newpath,
                                                       result_offset );
    if ( !error )
      *result_file_name = newpath;
    else
      FT_FREE( newpath );

    return error;
  }


  static FT_Error
  raccess_guess_apple_generic( FT_Library  library,
                               FT_Stream   stream,
                               char *      base_file_name,
                               FT_Int32    magic,
                               FT_Long    *result_offset )
  {
    FT_Int32   magic_from_stream;
    FT_Error   error;
    FT_Int32   version_number = 0;
    FT_UShort  n_of_entries;

    int        i;
    FT_UInt32  entry_id, entry_offset, entry_length = 0;

    const FT_UInt32  resource_fork_entry_id = 0x2;

    FT_UNUSED( library );
    FT_UNUSED( base_file_name );
    FT_UNUSED( version_number );
    FT_UNUSED( entry_length   );


    if ( FT_READ_LONG( magic_from_stream ) )
      return error;
    if ( magic_from_stream != magic )
      return FT_Err_Unknown_File_Format;

    if ( FT_READ_LONG( version_number ) )
      return error;

    /* filler */
    error = FT_Stream_Skip( stream, 16 );
    if ( error )
      return error;

    if ( FT_READ_USHORT( n_of_entries ) )
      return error;
    if ( n_of_entries == 0 )
      return FT_Err_Unknown_File_Format;

    for ( i = 0; i < n_of_entries; i++ )
    {
      if ( FT_READ_LONG( entry_id ) )
        return error;
      if ( entry_id == resource_fork_entry_id )
      {
        if ( FT_READ_LONG( entry_offset ) ||
             FT_READ_LONG( entry_length ) )
          continue;
        *result_offset = entry_offset;

        return FT_Err_Ok;
      }
      else
        FT_Stream_Skip( stream, 4 + 4 );    /* offset + length */
      }

    return FT_Err_Unknown_File_Format;
  }


  static FT_Error
  raccess_guess_linux_double_from_file_name( FT_Library  library,
                                             char *      file_name,
                                             FT_Long    *result_offset )
  {
    FT_Open_Args  args2;
    FT_Stream     stream2;
    char *        nouse = NULL;
    FT_Error      error;


    args2.flags    = FT_OPEN_PATHNAME;
    args2.pathname = file_name;
    error = FT_Stream_New( library, &args2, &stream2 );
    if ( error )
      return error;

    error = raccess_guess_apple_double( library, stream2, file_name,
                                        &nouse, result_offset );

    FT_Stream_Free( stream2, 0 );

    return error;
  }


  static char*
  raccess_make_file_name( FT_Memory    memory,
                          const char  *original_name,
                          const char  *insertion )
  {
    char*        new_name;
    char*        tmp;
    const char*  slash;
    unsigned     new_length;
    FT_Error     error = FT_Err_Ok;

    FT_UNUSED( error );


    new_length = ft_strlen( original_name ) + ft_strlen( insertion );
    if ( FT_ALLOC( new_name, new_length + 1 ) )
      return NULL;

    tmp = ft_strrchr( original_name, '/' );
    if ( tmp )
    {
      ft_strncpy( new_name, original_name, tmp - original_name + 1 );
      new_name[tmp - original_name + 1] = '\0';
      slash = tmp + 1;
    }
    else
    {
      slash       = original_name;
      new_name[0] = '\0';
    }

    ft_strcat( new_name, insertion );
    ft_strcat( new_name, slash );

    return new_name;
  }


#else   /* !FT_CONFIG_OPTION_GUESSING_EMBEDDED_RFORK */


  /*************************************************************************/
  /*                  Dummy function; just sets errors                     */
  /*************************************************************************/

  FT_BASE_DEF( void )
  FT_Raccess_Guess( FT_Library  library,
                    FT_Stream   stream,
                    char*       base_name,
                    char      **new_names,
                    FT_Long    *offsets,
                    FT_Error   *errors )
  {
    int  i;

    FT_UNUSED( library );
    FT_UNUSED( stream );
    FT_UNUSED( base_name );


    for ( i = 0; i < FT_RACCESS_N_RULES; i++ )
    {
      new_names[i] = NULL;
      offsets[i]   = 0;
      errors[i]    = FT_Err_Unimplemented_Feature;
    }
  }


#endif  /* !FT_CONFIG_OPTION_GUESSING_EMBEDDED_RFORK */


/* END */