C++ FT_FRAME_ENTER函数代码示例

  tt_face_load_gasp( TT_Face    face,
                     FT_Stream  stream )
  {
    FT_Error   error;
    FT_Memory  memory = stream->memory;

    FT_UInt        j,num_ranges;
    TT_GaspRange   gaspranges;


    /* the gasp table is optional */
    error = face->goto_table( face, TTAG_gasp, stream, 0 );
    if ( error )
      goto Exit;

    if ( FT_FRAME_ENTER( 4L ) )
      goto Exit;

    face->gasp.version   = FT_GET_USHORT();
    face->gasp.numRanges = FT_GET_USHORT();

    FT_FRAME_EXIT();

    /* only support versions 0 and 1 of the table */
    if ( face->gasp.version >= 2 )
    {
      face->gasp.numRanges = 0;
      error = SFNT_Err_Invalid_Table;
      goto Exit;
    }

    num_ranges = face->gasp.numRanges;
    FT_TRACE3(( "numRanges: %u\n", num_ranges ));

    if ( FT_QNEW_ARRAY( gaspranges, num_ranges ) ||
         FT_FRAME_ENTER( num_ranges * 4L )      )
      goto Exit;

    face->gasp.gaspRanges = gaspranges;

    for ( j = 0; j < num_ranges; j++ )
    {
      gaspranges[j].maxPPEM  = FT_GET_USHORT();
      gaspranges[j].gaspFlag = FT_GET_USHORT();

      FT_TRACE3(( "gaspRange %d: rangeMaxPPEM %5d, rangeGaspBehavior 0x%x\n",
                  j,
                  gaspranges[j].maxPPEM,
                  gaspranges[j].gaspFlag ));
    }

    FT_FRAME_EXIT();

  Exit:
    return error;
  }

  T1_Read_Metrics( FT_Face    t1_face,
                   FT_Stream  stream )
  {
    FT_Error  error;
    FT_Byte*  start;


    if ( FT_FRAME_ENTER( stream->size ) )
      return error;

    start = (FT_Byte*)stream->cursor;

    if ( stream->size >= ft_strlen( "StartFontMetrics" )    &&
         ft_strncmp( (const char*)start, "StartFontMetrics",
                     ft_strlen( "StartFontMetrics" ) ) == 0 )
      error = T1_Read_AFM( t1_face, stream );

    else if ( stream->size > 6                                &&
              start[0] == 0x00 && start[1] == 0x01            &&
              LITTLE_ENDIAN_UINT( start + 2 ) == stream->size )
      error = T1_Read_PFM( t1_face, stream );

    else
      error = T1_Err_Unknown_File_Format;

    FT_FRAME_EXIT();

    return error;
  }

  static void
  read_data_from_FT_Stream( png_structp  png,
                            png_bytep    data,
                            png_size_t   length )
  {
    FT_Error   error;
    png_voidp  p      = png_get_io_ptr( png );
    FT_Stream  stream = (FT_Stream)p;


    if ( FT_FRAME_ENTER( length ) )
    {
      FT_Error*  e = (FT_Error*)png_get_error_ptr( png );


      *e = FT_THROW( Invalid_Stream_Read );
      png_error( png, NULL );

      return;
    }

    memcpy( data, stream->cursor, length );

    FT_FRAME_EXIT();
  }

  static FT_Error
  check_type1_format( FT_Stream    stream,
                      const char*  header_string,
                      size_t       header_length )
  {
    FT_Error   error;
    FT_UShort  tag;
    FT_Long    size;


    if ( FT_STREAM_SEEK( 0 ) )
      goto Exit;

    error = read_pfb_tag( stream, &tag, &size );
    if ( error )
      goto Exit;

    if ( tag != 0x8001U && FT_STREAM_SEEK( 0 ) )
      goto Exit;

    if ( !FT_FRAME_ENTER( header_length ) )
    {
      error = 0;

      if ( ft_memcmp( stream->cursor, header_string, header_length ) != 0 )
        error = T1_Err_Unknown_File_Format;

      FT_FRAME_EXIT();
    }

  Exit:
    return error;
  }

  static FT_Error
  cff_index_load_offsets( CFF_Index  idx )
  {
    FT_Error   error  = 0;
    FT_Stream  stream = idx->stream;
    FT_Memory  memory = stream->memory;


    if ( idx->count > 0 && idx->offsets == NULL )
    {
      FT_Byte    offsize = idx->off_size;
      FT_ULong   data_size;
      FT_Byte*   p;
      FT_Byte*   p_end;
      FT_ULong*  poff;


      data_size = (FT_ULong)( idx->count + 1 ) * offsize;

      if ( FT_NEW_ARRAY( idx->offsets, idx->count + 1 ) ||
           FT_STREAM_SEEK( idx->start + 3 )             ||
           FT_FRAME_ENTER( data_size )                  )
        goto Exit;

      poff   = idx->offsets;
      p      = (FT_Byte*)stream->cursor;
      p_end  = p + data_size;

      switch ( offsize )
      {
      case 1:
        for ( ; p < p_end; p++, poff++ )
          poff[0] = p[0];
        break;

      case 2:
        for ( ; p < p_end; p += 2, poff++ )
          poff[0] = FT_PEEK_USHORT( p );
        break;

      case 3:
        for ( ; p < p_end; p += 3, poff++ )
          poff[0] = FT_PEEK_OFF3( p );
        break;

      default:
        for ( ; p < p_end; p += 4, poff++ )
          poff[0] = FT_PEEK_ULONG( p );
      }

      FT_FRAME_EXIT();
    }

  Exit:
    if ( error )
      FT_FREE( idx->offsets );

    return error;
  }

static FT_UInt32
tt_synth_sfnt_checksum( FT_Stream  stream,
                        FT_ULong   length )
{
    FT_Error   error;
    FT_UInt32  checksum = 0;
    FT_UInt    i;


    if ( FT_FRAME_ENTER( length ) )
        return 0;

    for ( ; length > 3; length -= 4 )
        checksum += (FT_UInt32)FT_GET_ULONG();

    for ( i = 3; length > 0; length--, i-- )
        checksum += (FT_UInt32)FT_GET_BYTE() << ( i * 8 );

    FT_FRAME_EXIT();

    return checksum;
}

  static FT_Error
  check_type1_format( FT_Stream    stream,
                      const char*  header_string,
                      size_t       header_length )
  {
    FT_Error   error;
    FT_UShort  tag;
    FT_ULong   dummy;


    if ( FT_STREAM_SEEK( 0 ) )
      goto Exit;

    error = read_pfb_tag( stream, &tag, &dummy );
    if ( error )
      goto Exit;

    /* We assume that the first segment in a PFB is always encoded as   */
    /* text.  This might be wrong (and the specification doesn't insist */
    /* on that), but we have never seen a counterexample.               */
    if ( tag != 0x8001U && FT_STREAM_SEEK( 0 ) )
      goto Exit;

    if ( !FT_FRAME_ENTER( header_length ) )
    {
      error = FT_Err_Ok;

      if ( ft_memcmp( stream->cursor, header_string, header_length ) != 0 )
        error = FT_THROW( Unknown_File_Format );

      FT_FRAME_EXIT();
    }

  Exit:
    return error;
  }

  tt_face_load_name( TT_Face    face,
                     FT_Stream  stream )
  {
    FT_Error      error;
    FT_Memory     memory = stream->memory;
    FT_ULong      table_pos, table_len;
    FT_ULong      storage_start, storage_limit;
    FT_UInt       count;
    TT_NameTable  table;

    static const FT_Frame_Field  name_table_fields[] =
    {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  TT_NameTableRec

      FT_FRAME_START( 6 ),
        FT_FRAME_USHORT( format ),
        FT_FRAME_USHORT( numNameRecords ),
        FT_FRAME_USHORT( storageOffset ),
      FT_FRAME_END
    };

    static const FT_Frame_Field  name_record_fields[] =
    {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  TT_NameEntryRec

      /* no FT_FRAME_START */
        FT_FRAME_USHORT( platformID ),
        FT_FRAME_USHORT( encodingID ),
        FT_FRAME_USHORT( languageID ),
        FT_FRAME_USHORT( nameID ),
        FT_FRAME_USHORT( stringLength ),
        FT_FRAME_USHORT( stringOffset ),
      FT_FRAME_END
    };


    table         = &face->name_table;
    table->stream = stream;

    error = face->goto_table( face, TTAG_name, stream, &table_len );
    if ( error )
      goto Exit;

    table_pos = FT_STREAM_POS();


    if ( FT_STREAM_READ_FIELDS( name_table_fields, table ) )
      goto Exit;

    /* Some popular Asian fonts have an invalid `storageOffset' value   */
    /* (it should be at least "6 + 12*num_names").  However, the string */
    /* offsets, computed as "storageOffset + entry->stringOffset", are  */
    /* valid pointers within the name table...                          */
    /*                                                                  */
    /* We thus can't check `storageOffset' right now.                   */
    /*                                                                  */
    storage_start = table_pos + 6 + 12*table->numNameRecords;
    storage_limit = table_pos + table_len;

    if ( storage_start > storage_limit )
    {
      FT_ERROR(( "tt_face_load_name: invalid `name' table\n" ));
      error = SFNT_Err_Name_Table_Missing;
      goto Exit;
    }

    /* Allocate the array of name records. */
    count                 = table->numNameRecords;
    table->numNameRecords = 0;

    if ( FT_NEW_ARRAY( table->names, count ) ||
         FT_FRAME_ENTER( count * 12 )        )
      goto Exit;

    /* Load the name records and determine how much storage is needed */
    /* to hold the strings themselves.                                */
    {
      TT_NameEntryRec*  entry = table->names;


      for ( ; count > 0; count-- )
      {
        if ( FT_STREAM_READ_FIELDS( name_record_fields, entry ) )
          continue;

        /* check that the name is not empty */
        if ( entry->stringLength == 0 )
          continue;

        /* check that the name string is within the table */
        entry->stringOffset += table_pos + table->storageOffset;
        if ( entry->stringOffset                       < storage_start ||
             entry->stringOffset + entry->stringLength > storage_limit )
        {
          /* invalid entry - ignore it */
          entry->stringOffset = 0;
          entry->stringLength = 0;
          continue;
//.........这里部分代码省略.........

static FT_Error
fnt_face_get_dll_font( FNT_Face  face,
                       FT_Int    face_index )
{
    FT_Error         error;
    FT_Stream        stream = FT_FACE( face )->stream;
    FT_Memory        memory = FT_FACE( face )->memory;
    WinMZ_HeaderRec  mz_header;


    face->font = 0;

    /* does it begin with an MZ header? */
    if ( FT_STREAM_SEEK( 0 )                                      ||
            FT_STREAM_READ_FIELDS( winmz_header_fields, &mz_header ) )
        goto Exit;

    error = FNT_Err_Unknown_File_Format;
    if ( mz_header.magic == WINFNT_MZ_MAGIC )
    {
        /* yes, now look for an NE header in the file */
        WinNE_HeaderRec  ne_header;


        if ( FT_STREAM_SEEK( mz_header.lfanew )                       ||
                FT_STREAM_READ_FIELDS( winne_header_fields, &ne_header ) )
            goto Exit;

        error = FNT_Err_Unknown_File_Format;
        if ( ne_header.magic == WINFNT_NE_MAGIC )
        {
            /* good, now look into the resource table for each FNT resource */
            FT_ULong   res_offset  = mz_header.lfanew +
                                     ne_header.resource_tab_offset;
            FT_UShort  size_shift;
            FT_UShort  font_count  = 0;
            FT_ULong   font_offset = 0;


            if ( FT_STREAM_SEEK( res_offset )                    ||
                    FT_FRAME_ENTER( ne_header.rname_tab_offset -
                                    ne_header.resource_tab_offset ) )
                goto Exit;

            size_shift = FT_GET_USHORT_LE();

            for (;;)
            {
                FT_UShort  type_id, count;


                type_id = FT_GET_USHORT_LE();
                if ( !type_id )
                    break;

                count = FT_GET_USHORT_LE();

                if ( type_id == 0x8008U )
                {
                    font_count  = count;
                    font_offset = (FT_ULong)( FT_STREAM_POS() + 4 +
                                              ( stream->cursor - stream->limit ) );
                    break;
                }

                stream->cursor += 4 + count * 12;
            }

            FT_FRAME_EXIT();

            if ( !font_count || !font_offset )
            {
                FT_TRACE2(( "this file doesn't contain any FNT resources!\n" ));
                error = FNT_Err_Unknown_File_Format;
                goto Exit;
            }

            face->root.num_faces = font_count;

            if ( face_index >= font_count )
            {
                error = FNT_Err_Bad_Argument;
                goto Exit;
            }

            if ( FT_NEW( face->font ) )
                goto Exit;

            if ( FT_STREAM_SEEK( font_offset + face_index * 12 ) ||
                    FT_FRAME_ENTER( 12 )                            )
                goto Fail;

            face->font->offset     = (FT_ULong)FT_GET_USHORT_LE() << size_shift;
            face->font->fnt_size   = (FT_ULong)FT_GET_USHORT_LE() << size_shift;
            face->font->size_shift = size_shift;

            stream->cursor += 8;

            FT_FRAME_EXIT();

//.........这里部分代码省略.........

  T1_Read_Metrics( FT_Face    t1_face,
                   FT_Stream  stream )
  {
    PSAux_Service  psaux;
    FT_Memory      memory  = stream->memory;
    AFM_ParserRec  parser;
    AFM_FontInfo   fi      = NULL;
    FT_Error       error   = FT_ERR( Unknown_File_Format );
    T1_Font        t1_font = &( (T1_Face)t1_face )->type1;


    if ( FT_NEW( fi )                   ||
         FT_FRAME_ENTER( stream->size ) )
      goto Exit;

    fi->FontBBox  = t1_font->font_bbox;
    fi->Ascender  = t1_font->font_bbox.yMax;
    fi->Descender = t1_font->font_bbox.yMin;

    psaux = (PSAux_Service)( (T1_Face)t1_face )->psaux;
    if ( psaux->afm_parser_funcs )
    {
      error = psaux->afm_parser_funcs->init( &parser,
                                             stream->memory,
                                             stream->cursor,
                                             stream->limit );

      if ( !error )
      {
        parser.FontInfo  = fi;
        parser.get_index = t1_get_index;
        parser.user_data = t1_font;

        error = psaux->afm_parser_funcs->parse( &parser );
        psaux->afm_parser_funcs->done( &parser );
      }
    }

    if ( FT_ERR_EQ( error, Unknown_File_Format ) )
    {
      FT_Byte*  start = stream->cursor;


      /* MS Windows allows versions up to 0x3FF without complaining */
      if ( stream->size > 6                              &&
           start[1] < 4                                  &&
           FT_PEEK_ULONG_LE( start + 2 ) == stream->size )
        error = T1_Read_PFM( t1_face, stream, fi );
    }

    if ( !error )
    {
      t1_font->font_bbox = fi->FontBBox;

      t1_face->bbox.xMin =   fi->FontBBox.xMin            >> 16;
      t1_face->bbox.yMin =   fi->FontBBox.yMin            >> 16;
      /* no `U' suffix here to 0xFFFF! */
      t1_face->bbox.xMax = ( fi->FontBBox.xMax + 0xFFFF ) >> 16;
      t1_face->bbox.yMax = ( fi->FontBBox.yMax + 0xFFFF ) >> 16;

      /* no `U' suffix here to 0x8000! */
      t1_face->ascender  = (FT_Short)( ( fi->Ascender  + 0x8000 ) >> 16 );
      t1_face->descender = (FT_Short)( ( fi->Descender + 0x8000 ) >> 16 );

      if ( fi->NumKernPair )
      {
        t1_face->face_flags |= FT_FACE_FLAG_KERNING;
        ( (T1_Face)t1_face )->afm_data = fi;
        fi = NULL;
      }
    }

  pfr_phy_font_load( PFR_PhyFont  phy_font,
                     FT_Stream    stream,
                     FT_UInt32    offset,
                     FT_UInt32    size )
  {
    FT_Error   error;
    FT_Memory  memory = stream->memory;
    FT_UInt    flags;
    FT_ULong   num_aux;
    FT_Byte*   p;
    FT_Byte*   limit;


    phy_font->memory = memory;
    phy_font->offset = offset;

    phy_font->kern_items      = NULL;
    phy_font->kern_items_tail = &phy_font->kern_items;

    if ( FT_STREAM_SEEK( offset ) ||
         FT_FRAME_ENTER( size )   )
      goto Exit;

    phy_font->cursor = stream->cursor;

    p     = stream->cursor;
    limit = p + size;

    PFR_CHECK( 15 );
    phy_font->font_ref_number    = PFR_NEXT_USHORT( p );
    phy_font->outline_resolution = PFR_NEXT_USHORT( p );
    phy_font->metrics_resolution = PFR_NEXT_USHORT( p );
    phy_font->bbox.xMin          = PFR_NEXT_SHORT( p );
    phy_font->bbox.yMin          = PFR_NEXT_SHORT( p );
    phy_font->bbox.xMax          = PFR_NEXT_SHORT( p );
    phy_font->bbox.yMax          = PFR_NEXT_SHORT( p );
    phy_font->flags      = flags = PFR_NEXT_BYTE( p );

    /* get the standard advance for non-proportional fonts */
    if ( !(flags & PFR_PHY_PROPORTIONAL) )
    {
      PFR_CHECK( 2 );
      phy_font->standard_advance = PFR_NEXT_SHORT( p );
    }

    /* load the extra items when present */
    if ( flags & PFR_PHY_EXTRA_ITEMS )
    {
      error = pfr_extra_items_parse( &p, limit,
                                     pfr_phy_font_extra_items, phy_font );

      if ( error )
        goto Fail;
    }

    /* In certain fonts, the auxiliary bytes contain interesting   */
    /* information.  These are not in the specification but can be */
    /* guessed by looking at the content of a few PFR0 fonts.      */
    PFR_CHECK( 3 );
    num_aux = PFR_NEXT_ULONG( p );

    if ( num_aux > 0 )
    {
      FT_Byte*  q = p;
      FT_Byte*  q2;


      PFR_CHECK_SIZE( num_aux );
      p += num_aux;

      while ( num_aux > 0 )
      {
        FT_UInt  length, type;


        if ( q + 4 > p )
          break;

        length = PFR_NEXT_USHORT( q );
        if ( length < 4 || length > num_aux )
          break;

        q2   = q + length - 2;
        type = PFR_NEXT_USHORT( q );

        switch ( type )
        {
        case 1:
          /* this seems to correspond to the font's family name, padded to */
          /* an even number of bytes with a zero byte appended if needed   */
          error = pfr_aux_name_load( q, length - 4U, memory,
                                     &phy_font->family_name );
          if ( error )
            goto Exit;
          break;

        case 2:
          if ( q + 32 > q2 )
            break;

//.........这里部分代码省略.........

  static FT_Error
  cff_encoding_load( CFF_Encoding  encoding,
                     CFF_Charset   charset,
                     FT_UInt       num_glyphs,
                     FT_Stream     stream,
                     FT_ULong      base_offset,
                     FT_ULong      offset )
  {
    FT_Error   error = CFF_Err_Ok;
    FT_UInt    count;
    FT_UInt    j;
    FT_UShort  glyph_sid;
    FT_UInt    glyph_code;


    /* Check for charset->sids.  If we do not have this, we fail. */
    if ( !charset->sids )
    {
      error = CFF_Err_Invalid_File_Format;
      goto Exit;
    }

    /* Zero out the code to gid/sid mappings. */
    for ( j = 0; j < 256; j++ )
    {
      encoding->sids [j] = 0;
      encoding->codes[j] = 0;
    }

    /* Note: The encoding table in a CFF font is indexed by glyph index;  */
    /* the first encoded glyph index is 1.  Hence, we read the character  */
    /* code (`glyph_code') at index j and make the assignment:            */
    /*                                                                    */
    /*    encoding->codes[glyph_code] = j + 1                             */
    /*                                                                    */
    /* We also make the assignment:                                       */
    /*                                                                    */
    /*    encoding->sids[glyph_code] = charset->sids[j + 1]               */
    /*                                                                    */
    /* This gives us both a code to GID and a code to SID mapping.        */

    if ( offset > 1 )
    {
      encoding->offset = base_offset + offset;

      /* we need to parse the table to determine its size */
      if ( FT_STREAM_SEEK( encoding->offset ) ||
           FT_READ_BYTE( encoding->format )   ||
           FT_READ_BYTE( count )              )
        goto Exit;

      switch ( encoding->format & 0x7F )
      {
      case 0:
        {
          FT_Byte*  p;


          /* By convention, GID 0 is always ".notdef" and is never */
          /* coded in the font.  Hence, the number of codes found  */
          /* in the table is `count+1'.                            */
          /*                                                       */
          encoding->count = count + 1;

          if ( FT_FRAME_ENTER( count ) )
            goto Exit;

          p = (FT_Byte*)stream->cursor;

          for ( j = 1; j <= count; j++ )
          {
            glyph_code = *p++;

            /* Make sure j is not too big. */
            if ( j < num_glyphs )
            {
              /* Assign code to GID mapping. */
              encoding->codes[glyph_code] = (FT_UShort)j;

              /* Assign code to SID mapping. */
              encoding->sids[glyph_code] = charset->sids[j];
            }
          }

          FT_FRAME_EXIT();
        }
        break;

      case 1:
        {
          FT_UInt  nleft;
          FT_UInt  i = 1;
          FT_UInt  k;


          encoding->count = 0;

          /* Parse the Format1 ranges. */
          for ( j = 0;  j < count; j++, i += nleft )
          {
//.........这里部分代码省略.........

  static FT_Error
  pfr_sort_kerning_pairs( FT_Stream    stream,
                          PFR_PhyFont  phy_font )
  {
    FT_Error      error;
    FT_Memory     memory = stream->memory;
    PFR_KernPair  pairs;
    PFR_KernItem  item;
    PFR_Char      chars     = phy_font->chars;
    FT_UInt       num_chars = phy_font->num_chars;
    FT_UInt       count;


   /* create kerning pairs array
    */
    if ( FT_NEW_ARRAY( phy_font->kern_pairs, phy_font->num_kern_pairs ) )
      goto Exit;

   /* load all kerning items into the array,
    * converting character codes into glyph indices
    */
    pairs = phy_font->kern_pairs;
    item  = phy_font->kern_items;
    count = 0;

    for ( ; item; item = item->next )
    {
      FT_UInt   limit = count + item->pair_count;
      FT_Byte*  p;


      if ( limit > phy_font->num_kern_pairs )
      {
        error = PFR_Err_Invalid_Table;
        goto Exit;
      }

      if ( FT_STREAM_SEEK( item->offset )                       ||
           FT_FRAME_ENTER( item->pair_count * item->pair_size ) )
        goto Exit;

      p = stream->cursor;

      for ( ; count < limit; count++ )
      {
        PFR_KernPair  pair = pairs + count;
        FT_UInt       char1, char2;
        FT_Int        kerning;


        if ( item->flags & PFR_KERN_2BYTE_CHAR )
        {
          char1 = FT_NEXT_USHORT( p );
          char2 = FT_NEXT_USHORT( p );
        }
        else
        {
          char1 = FT_NEXT_BYTE( p );
          char2 = FT_NEXT_BYTE( p );
        }

        if ( item->flags & PFR_KERN_2BYTE_ADJ )
          kerning = item->base_adj + FT_NEXT_SHORT( p );
        else
          kerning = item->base_adj + FT_NEXT_CHAR( p );

        pair->glyph1  = pfr_get_gindex( chars, num_chars, char1 );
        pair->glyph2  = pfr_get_gindex( chars, num_chars, char2 );
        pair->kerning = kerning;
      }

      FT_FRAME_EXIT();
    }

   /* sort the resulting array
    */
    ft_qsort( pairs, count,
              sizeof ( PFR_KernPairRec ),
              pfr_compare_kern_pairs );

  Exit:
    if ( error )
    {
     /* disable kerning data in case of error
      */
      phy_font->num_kern_pairs = 0;
    }

    return error;
  }

  static FT_Error
  cff_new_index( CFF_Index  idx,
                 FT_Stream  stream,
                 FT_Bool    load )
  {
    FT_Error   error;
    FT_Memory  memory = stream->memory;
    FT_UShort  count;


    FT_MEM_ZERO( idx, sizeof ( *idx ) );

    idx->stream = stream;
    if ( !FT_READ_USHORT( count ) &&
         count > 0                )
    {
      FT_Byte*   p;
      FT_Byte    offsize;
      FT_ULong   data_size;
      FT_ULong*  poff;


      /* there is at least one element; read the offset size,           */
      /* then access the offset table to compute the index's total size */
      if ( FT_READ_BYTE( offsize ) )
        goto Exit;

      idx->stream   = stream;
      idx->count    = count;
      idx->off_size = offsize;
      data_size     = (FT_ULong)( count + 1 ) * offsize;

      if ( FT_NEW_ARRAY( idx->offsets, count + 1 ) ||
           FT_FRAME_ENTER( data_size )             )
        goto Exit;

      poff = idx->offsets;
      p    = (FT_Byte*)stream->cursor;

      for ( ; (FT_Short)count >= 0; count-- )
      {
        poff[0] = cff_get_offset( p, offsize );
        poff++;
        p += offsize;
      }

      FT_FRAME_EXIT();

      idx->data_offset = FT_STREAM_POS();
      data_size        = poff[-1] - 1;

      if ( load )
      {
        /* load the data */
        if ( FT_FRAME_EXTRACT( data_size, idx->bytes ) )
          goto Exit;
      }
      else
      {
        /* skip the data */
        if ( FT_STREAM_SKIP( data_size ) )
          goto Exit;
      }
    }

  Exit:
    if ( error )
      FT_FREE( idx->offsets );

    return error;
  }

  tt_face_load_font_dir( TT_Face    face,
                         FT_Stream  stream )
  {
    SFNT_HeaderRec  sfnt;
    FT_Error        error;
    FT_Memory       memory = stream->memory;
    TT_TableRec*    entry;
    FT_Int          nn;

    static const FT_Frame_Field  offset_table_fields[] =
    {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  SFNT_HeaderRec

      FT_FRAME_START( 8 ),
        FT_FRAME_USHORT( num_tables ),
        FT_FRAME_USHORT( search_range ),
        FT_FRAME_USHORT( entry_selector ),
        FT_FRAME_USHORT( range_shift ),
      FT_FRAME_END
    };


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

    /* read the offset table */

    sfnt.offset = FT_STREAM_POS();

    if ( FT_READ_ULONG( sfnt.format_tag )                    ||
         FT_STREAM_READ_FIELDS( offset_table_fields, &sfnt ) )
      goto Exit;

    /* many fonts don't have these fields set correctly */
#if 0
    if ( sfnt.search_range != 1 << ( sfnt.entry_selector + 4 )        ||
         sfnt.search_range + sfnt.range_shift != sfnt.num_tables << 4 )
      return FT_THROW( Unknown_File_Format );
#endif

    /* load the table directory */

    FT_TRACE2(( "-- Number of tables: %10u\n",    sfnt.num_tables ));
    FT_TRACE2(( "-- Format version:   0x%08lx\n", sfnt.format_tag ));

    if ( sfnt.format_tag != TTAG_OTTO )
    {
      /* check first */
      error = check_table_dir( &sfnt, stream );
      if ( error )
      {
        FT_TRACE2(( "tt_face_load_font_dir:"
                    " invalid table directory for TrueType\n" ));

        goto Exit;
      }
    }

    face->num_tables = sfnt.num_tables;
    face->format_tag = sfnt.format_tag;

    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;

    FT_TRACE2(( "\n"
                "  tag    offset    length   checksum\n"
                "  ----------------------------------\n" ));

    for ( nn = 0; nn < sfnt.num_tables; nn++ )
    {
      entry->Tag      = FT_GET_TAG4();
      entry->CheckSum = FT_GET_ULONG();
      entry->Offset   = FT_GET_ULONG();
      entry->Length   = FT_GET_ULONG();

      /* ignore invalid tables that can't be sanitized */

      if ( entry->Offset > stream->size )
        continue;
      else if ( entry->Length > stream->size - entry->Offset )
      {
        if ( entry->Tag == TTAG_hmtx ||
             entry->Tag == TTAG_vmtx )
        {
#ifdef FT_DEBUG_LEVEL_TRACE
          FT_ULong  old_length = entry->Length;
#endif


          /* make metrics table length a multiple of 4 */
          entry->Length = ( stream->size - entry->Offset ) & ~3U;

          FT_TRACE2(( "  %c%c%c%c  %08lx  %08lx  %08lx"
                      " (sanitized; original length %08lx)\n",
//.........这里部分代码省略.........