ttload.c

qt-embedded-2.3.8.tar.gz源码

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

  Exit:
    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_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_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_LookUp_Table( face, tag );
      if ( !table )
      {
        error = TT_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 TT_Err_Ok;
    }

    if ( length )
      size = *length;

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

  Exit:
    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_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_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_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_Load_Generic_Table: Font table is missing!\n" ));
      goto Exit;
    }

    header = &face->header;

    if ( 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_Load_Generic_Table: Font table loaded.\n" ));

  Exit:
    return error;
  }


  FT_LOCAL_DEF
  FT_Error  TT_Load_Header( TT_Face    face,
                            FT_Stream  stream )
  {
    return TT_Load_Generic_Header( face, stream, TTAG_head );
  }


#ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS

  FT_LOCAL_DEF
  FT_Error  TT_Load_Bitmap_Header( TT_Face    face,
                                   FT_Stream  stream )
  {
    return TT_Load_Generic_Header( face, stream, TTAG_bhed );
  }

#endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Load_MaxProfile                                                 */
  /*                                                                       */
  /* <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_Load_MaxProfile( TT_Face    face,
                                FT_Stream  stream )
  {
    FT_Error        error;
    TT_MaxProfile*  maxProfile = &face->max_profile;

    const FT_Frame_Field  maxp_fields[] =
    {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  TT_MaxProfile

      FT_FRAME_START( 32 ),
        FT_FRAME_ULONG ( version ),
        FT_FRAME_USHORT( numGlyphs ),
        FT_FRAME_USHORT( maxPoints ),
        FT_FRAME_USHORT( maxContours ),
        FT_FRAME_USHORT( maxCompositePoints ),
        FT_FRAME_USHORT( maxCompositeContours ),
        FT_FRAME_USHORT( maxZones ),
        FT_FRAME_USHORT( maxTwilightPoints ),
        FT_FRAME_USHORT( maxStorage ),
        FT_FRAME_USHORT( maxFunctionDefs ),
        FT_FRAME_USHORT( maxInstructionDefs ),
        FT_FRAME_USHORT( maxStackElements ),
        FT_FRAME_USHORT( maxSizeOfInstructions ),
        FT_FRAME_USHORT( maxComponentElements ),
        FT_FRAME_USHORT( maxComponentDepth ),
      FT_FRAME_END };


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

    error = face->goto_table( face, TTAG_maxp, stream, 0 );
    if ( error )
      goto Exit;

    if ( READ_Fields( maxp_fields, maxProfile ) )
      goto Exit;

    /* XXX: an adjustment that is necessary to load certain */
    /*      broken fonts like `Keystrokes MT' :-(           */
    /*                                                      */
    /*   We allocate 64 function entries by default when    */
    /*   the maxFunctionDefs field is null.                 */

    if ( maxProfile->maxFunctionDefs == 0 )
      maxProfile->maxFunctionDefs = 64;

    face->root.num_glyphs = maxProfile->numGlyphs;

    face->root.internal->max_points = MAX( maxProfile->maxCompositePoints,
                                           maxProfile->maxPoints );

    face->root.internal->max_contours = MAX( maxProfile->maxCompositeContours,
                                             maxProfile->maxContours );

    face->max_components = (FT_ULong)maxProfile->maxComponentElements +
                           maxProfile->maxComponentDepth;

    /* XXX: some fonts have maxComponents set to 0; we will */
    /*      then use 16 of them by default.                 */
    if ( face->max_components == 0 )
      face->max_components = 16;

    /* We also increase maxPoints and maxContours in order to support */
    /* some broken fonts.                                             */
    face->root.internal->max_points   += 8;
    face->root.internal->max_contours += 4;

    FT_TRACE2(( "MAXP loaded.\n" ));

  Exit:
    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Load_Metrics                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Loads the horizontal or vertical metrics table into a face object. */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face     :: A handle to the target face object.                    */
  /*    stream   :: The input stream.                                      */
  /*    vertical :: A boolean flag.  If set, load vertical metrics.        */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  static
  FT_Error  TT_Load_Metrics( TT_Face    face,
                             FT_Stream  stream,
                             FT_Bool    vertical )
  {
    FT_Error   error;
    FT_Memory  memory = stream->memory;

    FT_ULong   table_len;
    FT_Long    num_shorts, num_longs, num_shorts_checked;

    TT_LongMetrics**   longs;
    TT_ShortMetrics**  shorts;


    FT_TRACE2(( "TT_Load_%s_Metrics: %08p\n", vertical ? "Vertical"
                                                       : "Horizontal",
                                              face ));

    if ( vertical )
    {
      /* The table is optional, quit silently if it wasn't found       */
      /* XXX: Some fonts have a valid vertical header with a non-null  */
      /*      `number_of_VMetrics' fields, but no corresponding `vmtx' */
      /*      table to get the metrics from (e.g. mingliu).            */
      /*                                                               */
      /*      For safety, we set the field to 0!                       */
      /*                                                               */
      error = face->goto_table( face, TTAG_vmtx, stream, &table_len );
      if ( error )
      {
        /* Set number_Of_VMetrics to 0! */
        FT_TRACE2(( "  no vertical header in file.\n" ));
        face->vertical.number_Of_VMetrics = 0;
        error = TT_Err_Ok;
        goto Exit;
      }

      num_longs = face->vertical.number_Of_VMetrics;
      longs     = (TT_LongMetrics**)&face->vertical.long_metrics;
      shorts    = (TT_ShortMetrics**)&face->vertical.short_metrics;
    }
    else