ttload.c

qt-x11-opensource-src-4.1.4.tar.gz源码

        goto Exit;

      /* now read the offsets of each font in the file */
      if ( FT_NEW_ARRAY( face->ttc_header.offsets, face->ttc_header.count ) ||
           FT_FRAME_ENTER( face->ttc_header.count * 4L )                    )
        goto Exit;

      for ( n = 0; n < face->ttc_header.count; n++ )
        face->ttc_header.offsets[n] = FT_GET_ULONG();

      FT_FRAME_EXIT();

      /* check face index */
      if ( face_index >= face->ttc_header.count )
      {
        error = SFNT_Err_Bad_Argument;
        goto Exit;
      }

      /* seek to the appropriate TrueType file, then read tag */
      offset = face->ttc_header.offsets[face_index];

      if ( FT_STREAM_SEEK( offset )   ||
           FT_READ_LONG( format_tag ) )
        goto Exit;
    }

    /* the format tag was read, now check the rest of the header */
    sfnt->format_tag = format_tag;
    sfnt->offset     = offset;

    if ( FT_STREAM_READ_FIELDS( sfnt_header_fields, sfnt ) )
      goto Exit;

    /* now check the sfnt directory */
    error = sfnt_dir_check( stream, offset, sfnt->num_tables );
    if ( error )
    {
      FT_TRACE2(( "tt_face_load_sfnt_header: file is not SFNT!\n" ));
      error = SFNT_Err_Unknown_File_Format;
      goto Exit;
    }

    /* disallow face index values > 0 for non-TTC files */
    if ( font_format_tag != TTAG_ttcf && face_index > 0 )
      error = SFNT_Err_Bad_Argument;

  Exit:
    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    tt_face_load_directory                                             */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Loads the table directory into a face object.                      */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    face   :: A handle to the target face object.                      */
  /*                                                                       */
  /* <Input>                                                               */
  /*    stream :: The input stream.                                        */
  /*                                                                       */
  /*    sfnt   :: The SFNT directory header.                               */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    The stream cursor must be at the font file's origin.               */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  tt_face_load_directory( TT_Face      face,
                          FT_Stream    stream,
                          SFNT_Header  sfnt )
  {
    FT_Error     error;
    FT_Memory    memory = stream->memory;

    TT_TableRec  *entry, *limit;


    FT_TRACE2(( "tt_face_load_directory: %08p\n", face ));

    FT_TRACE2(( "-- Tables count:   %12u\n",  sfnt->num_tables ));
    FT_TRACE2(( "-- Format version: %08lx\n", sfnt->format_tag ));

    face->num_tables = sfnt->num_tables;

    if ( FT_QNEW_ARRAY( face->dir_tables, face->num_tables ) )
      goto Exit;

    if ( FT_STREAM_SEEK( sfnt->offset + 12 )      ||
         FT_FRAME_ENTER( face->num_tables * 16L ) )
      goto Exit;

    entry = face->dir_tables;
    limit = entry + face->num_tables;

    for ( ; entry < limit; entry++ )
    {                    /* loop through the tables and get all entries */
      entry->Tag      = FT_GET_TAG4();
      entry->CheckSum = FT_GET_ULONG();
      entry->Offset   = FT_GET_LONG();
      entry->Length   = FT_GET_LONG();

      FT_TRACE2(( "  %c%c%c%c  -  %08lx  -  %08lx\n",
                  (FT_Char)( entry->Tag >> 24 ),
                  (FT_Char)( entry->Tag >> 16 ),
                  (FT_Char)( entry->Tag >> 8  ),
                  (FT_Char)( entry->Tag       ),
                  entry->Offset,
                  entry->Length ));
    }

    FT_FRAME_EXIT();

    FT_TRACE2(( "Directory loaded\n\n" ));

  Exit:
    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    tt_face_load_any                                                   */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Loads any font table into client memory.                           */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face   :: The face object to look for.                             */
  /*                                                                       */
  /*    tag    :: The tag of table to load.  Use the value 0 if you want   */
  /*              to access the whole font file, else set this parameter   */
  /*              to a valid TrueType table tag that you can forge with    */
  /*              the MAKE_TT_TAG macro.                                   */
  /*                                                                       */
  /*    offset :: The starting offset in the table (or the file if         */
  /*              tag == 0).                                               */
  /*                                                                       */
  /*    length :: The address of the decision variable:                    */
  /*                                                                       */
  /*                If length == NULL:                                     */
  /*                  Loads the whole table.  Returns an error if          */
  /*                  `offset' == 0!                                       */
  /*                                                                       */
  /*                If *length == 0:                                       */
  /*                  Exits immediately; returning the length of the given */
  /*                  table or of the font file, depending on the value of */
  /*                  `tag'.                                               */
  /*                                                                       */
  /*                If *length != 0:                                       */
  /*                  Loads the next `length' bytes of table or font,      */
  /*                  starting at offset `offset' (in table or font too).  */
  /*                                                                       */
  /* <Output>                                                              */
  /*    buffer :: The address of target buffer.                            */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  tt_face_load_any( TT_Face    face,
                    FT_ULong   tag,
                    FT_Long    offset,
                    FT_Byte*   buffer,
                    FT_ULong*  length )
  {
    FT_Error   error;
    FT_Stream  stream;
    TT_Table   table;
    FT_ULong   size;


    if ( tag != 0 )
    {
      /* look for tag in font directory */
      table = tt_face_lookup_table( face, tag );
      if ( !table )
      {
        error = SFNT_Err_Table_Missing;
        goto Exit;
      }

      offset += table->Offset;
      size    = table->Length;
    }
    else
      /* tag == 0 -- the user wants to access the font file directly */
      size = face->root.stream->size;

    if ( length && *length == 0 )
    {
      *length = size;

      return SFNT_Err_Ok;
    }

    if ( length )
      size = *length;

    stream = face->root.stream;
    /* the `if' is syntactic sugar for picky compilers */
    if ( FT_STREAM_READ_AT( offset, buffer, size ) )
      goto Exit;

  Exit:
    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    tt_face_load_generic_header                                        */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Loads the TrueType table `head' or `bhed'.                         */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face   :: A handle to the target face object.                      */
  /*                                                                       */
  /*    stream :: The input stream.                                        */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  static FT_Error
  tt_face_load_generic_header( TT_Face    face,
                               FT_Stream  stream,
                               FT_ULong   tag )
  {
    FT_Error    error;
    TT_Header*  header;

    static const FT_Frame_Field  header_fields[] =
    {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  TT_Header

      FT_FRAME_START( 54 ),
        FT_FRAME_ULONG ( Table_Version ),
        FT_FRAME_ULONG ( Font_Revision ),
        FT_FRAME_LONG  ( CheckSum_Adjust ),
        FT_FRAME_LONG  ( Magic_Number ),
        FT_FRAME_USHORT( Flags ),
        FT_FRAME_USHORT( Units_Per_EM ),
        FT_FRAME_LONG  ( Created[0] ),
        FT_FRAME_LONG  ( Created[1] ),
        FT_FRAME_LONG  ( Modified[0] ),
        FT_FRAME_LONG  ( Modified[1] ),
        FT_FRAME_SHORT ( xMin ),
        FT_FRAME_SHORT ( yMin ),
        FT_FRAME_SHORT ( xMax ),
        FT_FRAME_SHORT ( yMax ),
        FT_FRAME_USHORT( Mac_Style ),
        FT_FRAME_USHORT( Lowest_Rec_PPEM ),
        FT_FRAME_SHORT ( Font_Direction ),
        FT_FRAME_SHORT ( Index_To_Loc_Format ),
        FT_FRAME_SHORT ( Glyph_Data_Format ),
      FT_FRAME_END
    };


    FT_TRACE2(( "tt_face_load_generic_header: "
                "%08p, looking up font table `%c%c%c%c'.\n",
                face,
                (FT_Char)( tag >> 24 ),
                (FT_Char)( tag >> 16 ),
                (FT_Char)( tag >> 8  ),
                (FT_Char)( tag       ) ));

    error = face->goto_table( face, tag, stream, 0 );
    if ( error )
    {
      FT_TRACE2(( "tt_face_load_generic_header: Font table is missing!\n" ));
      goto Exit;
    }

    header = &face->header;

    if ( FT_STREAM_READ_FIELDS( header_fields, header ) )
      goto Exit;

    FT_TRACE2(( "    Units per EM: %8u\n", header->Units_Per_EM ));
    FT_TRACE2(( "    IndexToLoc:   %8d\n", header->Index_To_Loc_Format ));
    FT_TRACE2(( "tt_face_load_generic_header: Font table loaded.\n" ));

  Exit:
    return error;
  }


  FT_LOCAL_DEF( FT_Error )
  tt_face_load_header( TT_Face    face,
                       FT_Stream  stream )
  {
    return tt_face_load_generic_header( face, stream, TTAG_head );
  }


#ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS

  FT_LOCAL_DEF( FT_Error )
  tt_face_load_bitmap_header( TT_Face    face,
                              FT_Stream  stream )
  {
    return tt_face_load_generic_header( face, stream, TTAG_bhed );
  }

#endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    tt_face_load_max_profile                                           */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Loads the maximum profile into a face object.                      */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face   :: A handle to the target face object.                      */
  /*                                                                       */
  /*    stream :: The input stream.                                        */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  tt_face_load_max_profile( TT_Face    face,
                            FT_Stream  stream )
  {
    FT_Error        error;
    TT_MaxProfile*  maxProfile = &face->max_profile;

    const FT_Frame_Field  maxp_fields[] =