ttload.c

a very goog book

  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Free_Names                                                      */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Frees the name records.                                            */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face :: A handle to the target face object.                        */
  /*                                                                       */
  FT_LOCAL_DEF( void )
  TT_Free_Names( TT_Face  face )
  {
    FT_Memory     memory = face->root.driver->root.memory;
    TT_NameTable  table  = &face->name_table;
    TT_NameEntry  entry  = table->names;
    FT_UInt       count  = table->numNameRecords;


    for ( ; count > 0; count--, entry++ )
    {
      FT_FREE( entry->string );
      entry->stringLength = 0;
    }

    /* free strings table */
    FT_FREE( table->names );

    table->numNameRecords = 0;
    table->format         = 0;
    table->storageOffset  = 0;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Load_CMap                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Loads the cmap directory in a face object.  The cmaps itselves are */
  /*    loaded on demand in the `ttcmap.c' module.                         */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face   :: A handle to the target face object.                      */
  /*                                                                       */
  /*    stream :: A handle to the input stream.                            */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */

#ifdef FT_CONFIG_OPTION_USE_CMAPS

  FT_LOCAL_DEF( FT_Error )
  TT_Load_CMap( TT_Face    face,
                FT_Stream  stream )
  {
    FT_Error  error;


    error = face->goto_table( face, TTAG_cmap, stream, &face->cmap_size );
    if ( error )
    {
      FT_TRACE2(( "No `cmap' table in font !\n" ));
      error = SFNT_Err_CMap_Table_Missing;
      goto Exit;
    }

    if ( !FT_FRAME_EXTRACT( face->cmap_size, face->cmap_table ) )
      FT_TRACE2(( "`cmap' table loaded\n" ));
    else
    {
      FT_ERROR(( "`cmap' table is too short!\n" ));
      face->cmap_size = 0;
    }

  Exit:
    return error;
  }

#else /* !FT_CONFIG_OPTION_USE_CMAPS */

  FT_LOCAL_DEF( FT_Error )
  TT_Load_CMap( TT_Face    face,
                FT_Stream  stream )
  {
    FT_Error       error;
    FT_Memory      memory = stream->memory;
    FT_Long        table_start;
    TT_CMapDirRec  cmap_dir;

    const FT_Frame_Field  cmap_fields[] =
    {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  TT_CMapDirRec

      FT_FRAME_START( 4 ),
        FT_FRAME_USHORT( tableVersionNumber ),
        FT_FRAME_USHORT( numCMaps ),
      FT_FRAME_END
    };

    const FT_Frame_Field  cmap_rec_fields[] =
    {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  TT_CMapTableRec

      FT_FRAME_START( 4 ),
        FT_FRAME_USHORT( format ),
        FT_FRAME_USHORT( length ),
      FT_FRAME_END
    };


    FT_TRACE2(( "CMaps " ));

    error = face->goto_table( face, TTAG_cmap, stream, 0 );
    if ( error )
    {
      error = SFNT_Err_CMap_Table_Missing;
      goto Exit;
    }

    table_start = FT_STREAM_POS();

    if ( FT_STREAM_READ_FIELDS( cmap_fields, &cmap_dir ) )
      goto Exit;

    /* reserve space in face table for cmap tables */
    if ( FT_NEW_ARRAY( face->charmaps, cmap_dir.numCMaps ) )
      goto Exit;

    face->num_charmaps = cmap_dir.numCMaps;
    {
      TT_CharMap  charmap = face->charmaps;
      TT_CharMap  limit   = charmap + face->num_charmaps;


      /* read the header of each charmap first */
      if ( FT_FRAME_ENTER( face->num_charmaps * 8L ) )
        goto Exit;

      for ( ; charmap < limit; charmap++ )
      {
        TT_CMapTable  cmap;


        charmap->root.face = (FT_Face)face;
        cmap               = &charmap->cmap;

        cmap->loaded             = FALSE;
        cmap->platformID         = FT_GET_USHORT();
        cmap->platformEncodingID = FT_GET_USHORT();
        cmap->offset             = (FT_ULong)FT_GET_LONG();
      }

      FT_FRAME_EXIT();

      /* now read the rest of each table */
      for ( charmap = face->charmaps; charmap < limit; charmap++ )
      {
        TT_CMapTable  cmap = &charmap->cmap;


        if ( FT_STREAM_SEEK( table_start + (FT_Long)cmap->offset ) ||
             FT_STREAM_READ_FIELDS( cmap_rec_fields, cmap )        )
          goto Exit;

        cmap->offset = FT_STREAM_POS();
      }
    }

    FT_TRACE2(( "loaded\n" ));

  Exit:
    return error;
  }

#endif /* !FT_CONFIG_OPTION_USE_CMAPS */


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Load_OS2                                                        */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Loads the OS2 table.                                               */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face   :: A handle to the target face object.                      */
  /*                                                                       */
  /*    stream :: A handle to the input stream.                            */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  TT_Load_OS2( TT_Face    face,
               FT_Stream  stream )
  {
    FT_Error  error;
    TT_OS2*   os2;

    const FT_Frame_Field  os2_fields[] =
    {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  TT_OS2

      FT_FRAME_START( 78 ),
        FT_FRAME_USHORT( version ),
        FT_FRAME_SHORT ( xAvgCharWidth ),
        FT_FRAME_USHORT( usWeightClass ),
        FT_FRAME_USHORT( usWidthClass ),
        FT_FRAME_SHORT ( fsType ),
        FT_FRAME_SHORT ( ySubscriptXSize ),
        FT_FRAME_SHORT ( ySubscriptYSize ),
        FT_FRAME_SHORT ( ySubscriptXOffset ),
        FT_FRAME_SHORT ( ySubscriptYOffset ),
        FT_FRAME_SHORT ( ySuperscriptXSize ),
        FT_FRAME_SHORT ( ySuperscriptYSize ),
        FT_FRAME_SHORT ( ySuperscriptXOffset ),
        FT_FRAME_SHORT ( ySuperscriptYOffset ),
        FT_FRAME_SHORT ( yStrikeoutSize ),
        FT_FRAME_SHORT ( yStrikeoutPosition ),
        FT_FRAME_SHORT ( sFamilyClass ),
        FT_FRAME_BYTE  ( panose[0] ),
        FT_FRAME_BYTE  ( panose[1] ),
        FT_FRAME_BYTE  ( panose[2] ),
        FT_FRAME_BYTE  ( panose[3] ),
        FT_FRAME_BYTE  ( panose[4] ),
        FT_FRAME_BYTE  ( panose[5] ),
        FT_FRAME_BYTE  ( panose[6] ),
        FT_FRAME_BYTE  ( panose[7] ),
        FT_FRAME_BYTE  ( panose[8] ),
        FT_FRAME_BYTE  ( panose[9] ),
        FT_FRAME_ULONG ( ulUnicodeRange1 ),
        FT_FRAME_ULONG ( ulUnicodeRange2 ),
        FT_FRAME_ULONG ( ulUnicodeRange3 ),
        FT_FRAME_ULONG ( ulUnicodeRange4 ),
        FT_FRAME_BYTE  ( achVendID[0] ),
        FT_FRAME_BYTE  ( achVendID[1] ),
        FT_FRAME_BYTE  ( achVendID[2] ),
        FT_FRAME_BYTE  ( achVendID[3] ),

        FT_FRAME_USHORT( fsSelection ),
        FT_FRAME_USHORT( usFirstCharIndex ),
        FT_FRAME_USHORT( usLastCharIndex ),
        FT_FRAME_SHORT ( sTypoAscender ),
        FT_FRAME_SHORT ( sTypoDescender ),
        FT_FRAME_SHORT ( sTypoLineGap ),
        FT_FRAME_USHORT( usWinAscent ),
        FT_FRAME_USHORT( usWinDescent ),
      FT_FRAME_END
    };

    const FT_Frame_Field  os2_fields_extra[] =
    {
      FT_FRAME_START( 8 ),
        FT_FRAME_ULONG( ulCodePageRange1 ),
        FT_FRAME_ULONG( ulCodePageRange2 ),
      FT_FRAME_END
    };

    const FT_Frame_Field  os2_fields_extra2[] =
    {
      FT_FRAME_START( 10 ),
        FT_FRAME_SHORT ( sxHeight ),
        FT_FRAME_SHORT ( sCapHeight ),
        FT_FRAME_USHORT( usDefaultChar ),
        FT_FRAME_USHORT( usBreakChar ),
        FT_FRAME_USHORT( usMaxContext ),
      FT_FRAME_END
    };


    FT_TRACE2(( "OS/2 Table " ));

    /* We now support old Mac fonts where the OS/2 table doesn't  */
    /* exist.  Simply put, we set the `version' field to 0xFFFF   */
    /* and test this value each time we need to access the table. */
    error = face->goto_table( face, TTAG_OS2, stream, 0 );
    if ( error )
    {
      FT_TRACE2(( "is missing!\n" ));
      face->os2.version = 0xFFFFU;
      error = SFNT_Err_Ok;
      goto Exit;
    }

    os2 = &face->os2;

    if ( FT_STREAM_READ_FIELDS( os2_fields, os2 ) )
      goto Exit;

    os2->ulCodePageRange1 = 0;
    os2->ulCodePageRange2 = 0;
    os2->sxHeight         = 0;
    os2->sCapHeight       = 0;
    os2->usDefaultChar    = 0;
    os2->usBreakChar      = 0;
    os2->usMaxContext     = 0;

    if ( os2->version >= 0x0001 )
    {
      /* only version 1 tables */
      if ( FT_STREAM_READ_FIELDS( os2_fields_extra, os2 ) )
        goto Exit;

      if ( os2->version >= 0x0002 )
      {
        /* only version 2 tables */
        if ( FT_STREAM_READ_FIELDS( os2_fields_extra2, os2 ) )
          goto Exit;
      }
    }

    FT_TRACE2(( "loaded\n" ));

  Exit:
    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Load_Postscript                                                 */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Loads the Postscript table.                                        */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face   :: A handle to the target face object.                      */
  /*                                                                       */
  /*    stream :: A handle to the input stream.                            */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  TT_Load_PostScript( TT_Face    face,
                      FT_Stream  stream )
  {
    FT_Error        error;
    TT_Postscript*  post = &face->postscript;

    static const FT_Frame_Field  post_fields[] =