gxvcommn.c

奇趣公司比较新的qt/emd版本

  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                          SFNT NAME                            *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  FT_LOCAL_DEF( void )
  gxv_sfntName_validate( FT_UShort      name_index,
                         FT_UShort      min_index,
                         FT_UShort      max_index,
                         GXV_Validator  valid )
  {
    FT_SfntName  name;
    FT_UInt      i;
    FT_UInt      nnames;


    GXV_NAME_ENTER( "sfntName" );

    if ( name_index < min_index || max_index < name_index )
      FT_INVALID_FORMAT;

    nnames = FT_Get_Sfnt_Name_Count( valid->face );
    for ( i = 0; i < nnames; i++ )
    {
      if ( FT_Get_Sfnt_Name( valid->face, i, &name ) != FT_Err_Ok )
        continue ;

      if ( name.name_id == name_index )
        goto Out;
    }

    GXV_TRACE(( "  nameIndex = %d (UNTITLED)\n", name_index ));
    FT_INVALID_DATA;
    goto Exit;  /* make compiler happy */

  Out:
    FT_TRACE1(( "  nameIndex = %d (", name_index ));
    GXV_TRACE_HEXDUMP_SFNTNAME( name );
    FT_TRACE1(( ")\n" ));

  Exit:
    GXV_EXIT;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                          STATE TABLE                          *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /* -------------------------- Class Table --------------------------- */

  /*
   * highestClass specifies how many classes are defined in this
   * Class Subtable.  Apple spec does not mention whether undefined
   * holes in the class (e.g.: 0-3 are predefined, 4 is unused, 5 is used)
   * are permitted.  At present, holes in a defined class are not checked.
   *   -- suzuki toshiya <[e-mail]>
   */

  static void
  gxv_ClassTable_validate( FT_Bytes       table,
                           FT_UShort*     length_p,
                           FT_UShort      stateSize,
                           FT_Byte*       maxClassID_p,
                           GXV_Validator  valid )
  {
    FT_Bytes   p     = table;
    FT_Bytes   limit = table + *length_p;
    FT_UShort  firstGlyph;
    FT_UShort  nGlyphs;


    GXV_NAME_ENTER( "ClassTable" );

    *maxClassID_p = 3;  /* Classes 0, 2, and 3 are predefined */

    GXV_LIMIT_CHECK( 2 + 2 );
    firstGlyph = FT_NEXT_USHORT( p );
    nGlyphs    = FT_NEXT_USHORT( p );

    GXV_TRACE(( " (firstGlyph = %d, nGlyphs = %d)\n", firstGlyph, nGlyphs ));

    if ( !nGlyphs )
      goto Out;

    gxv_glyphid_validate( (FT_UShort)( firstGlyph + nGlyphs ), valid );

    {
      FT_Byte    nGlyphInClass[256];
      FT_Byte    classID;
      FT_UShort  i;


      ft_memset( nGlyphInClass, 0, 256 );


      for ( i = 0; i < nGlyphs; i++ )
      {
        GXV_LIMIT_CHECK( 1 );
        classID = FT_NEXT_BYTE( p );
        switch ( classID )
        {
          /* following classes should not appear in class array */
        case 0:             /* end of text */
        case 2:             /* out of bounds */
        case 3:             /* end of line */
          FT_INVALID_DATA;
          break;

        case 1:             /* out of bounds */
        default:            /* user-defined: 4 - ( stateSize - 1 ) */
          if ( classID >= stateSize )
            FT_INVALID_DATA;   /* assign glyph to undefined state */

          nGlyphInClass[classID]++;
          break;
        }
      }
      *length_p = (FT_UShort)( p - table );

      /* scan max ClassID in use */
      for ( i = 0; i < stateSize; i++ )
        if ( ( 3 < i ) && ( nGlyphInClass[i] > 0 ) )
          *maxClassID_p = (FT_Byte)i;  /* XXX: Check Range? */
    }

  Out:
    GXV_TRACE(( "Declared stateSize=0x%02x, Used maxClassID=0x%02x\n",
                stateSize, *maxClassID_p ));
    GXV_EXIT;
  }


  /* --------------------------- State Array ----------------------------- */

  static void
  gxv_StateArray_validate( FT_Bytes       table,
                           FT_UShort*     length_p,
                           FT_Byte        maxClassID,
                           FT_UShort      stateSize,
                           FT_Byte*       maxState_p,
                           FT_Byte*       maxEntry_p,
                           GXV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_Bytes  limit = table + *length_p;
    FT_Byte   clazz;
    FT_Byte   entry;

    FT_UNUSED( stateSize ); /* for the non-debugging case */


    GXV_NAME_ENTER( "StateArray" );

    GXV_TRACE(( "parse %d bytes by stateSize=%d maxClassID=%d\n",
                (int)(*length_p), stateSize, (int)(maxClassID) ));

    /*
     * 2 states are predefined and must be described in StateArray:
     * state 0 (start of text), 1 (start of line)
     */
    GXV_LIMIT_CHECK( ( 1 + maxClassID ) * 2 );

    *maxState_p = 0;
    *maxEntry_p = 0;

    /* read if enough to read another state */
    while ( p + ( 1 + maxClassID ) <= limit )
    {
      (*maxState_p)++;
      for ( clazz = 0; clazz <= maxClassID; clazz++ )
      {
        entry = FT_NEXT_BYTE( p );
        *maxEntry_p = (FT_Byte)FT_MAX( *maxEntry_p, entry );
      }
    }
    GXV_TRACE(( "parsed: maxState=%d, maxEntry=%d\n",
                *maxState_p, *maxEntry_p ));

    *length_p = (FT_UShort)( p - table );

    GXV_EXIT;
  }


  /* --------------------------- Entry Table ----------------------------- */

  static void
  gxv_EntryTable_validate( FT_Bytes       table,
                           FT_UShort*     length_p,
                           FT_Byte        maxEntry,
                           FT_UShort      stateArray,
                           FT_UShort      stateArray_length,
                           FT_Byte        maxClassID,
                           FT_Bytes       statetable_table,
                           FT_Bytes       statetable_limit,
                           GXV_Validator  valid )
  {
    FT_Bytes  p     = table;
    FT_Bytes  limit = table + *length_p;
    FT_Byte   entry;
    FT_Byte   state;
    FT_Int    entrySize = 2 + 2 + GXV_GLYPHOFFSET_SIZE( statetable );

    GXV_XStateTable_GlyphOffsetDesc  glyphOffset;


    GXV_NAME_ENTER( "EntryTable" );

    GXV_TRACE(( "maxEntry=%d entrySize=%d\n", maxEntry, entrySize ));

    if ( ( maxEntry + 1 ) * entrySize > *length_p )
    {
      if ( valid->root->level >= FT_VALIDATE_PARANOID )
        FT_INVALID_TOO_SHORT;

      /* ftxvalidator and FontValidator both warn and continue */
      maxEntry = (FT_Byte)( *length_p / entrySize - 1 );
      GXV_TRACE(( "too large maxEntry, shrinking to %d fit EntryTable length\n",
                  maxEntry ));
    }

    for ( entry = 0; entry <= maxEntry; entry++ )
    {
      FT_UShort  newState;
      FT_UShort  flags;


      GXV_LIMIT_CHECK( 2 + 2 );
      newState = FT_NEXT_USHORT( p );
      flags    = FT_NEXT_USHORT( p );


      if ( newState < stateArray                     ||
           stateArray + stateArray_length < newState )
      {
        GXV_TRACE(( " newState offset 0x%04x is out of stateArray\n",
                    newState ));
        if ( valid->root->level >= FT_VALIDATE_PARANOID )
          FT_INVALID_OFFSET;
        continue;
      }

      if ( 0 != ( ( newState - stateArray ) % ( 1 + maxClassID ) ) )
      {
        GXV_TRACE(( " newState offset 0x%04x is not aligned to %d-classes\n",
                    newState,  1 + maxClassID ));
        if ( valid->root->level >= FT_VALIDATE_PARANOID )
          FT_INVALID_OFFSET;
        continue;
      }

      state = (FT_Byte)( ( newState - stateArray ) / ( 1 + maxClassID ) );

      switch ( GXV_GLYPHOFFSET_FMT( statetable ) )
      {
      case GXV_GLYPHOFFSET_NONE:
        glyphOffset.uc = 0;  /* make compiler happy */
        break;

      case GXV_GLYPHOFFSET_UCHAR:
        glyphOffset.uc = FT_NEXT_BYTE( p );
        break;

      case GXV_GLYPHOFFSET_CHAR:
        glyphOffset.c = FT_NEXT_CHAR( p );
        break;

      case GXV_GLYPHOFFSET_USHORT:
        glyphOffset.u = FT_NEXT_USHORT( p );
        break;

      case GXV_GLYPHOFFSET_SHORT:
        glyphOffset.s = FT_NEXT_SHORT( p );
        break;

      case GXV_GLYPHOFFSET_ULONG:
        glyphOffset.ul = FT_NEXT_ULONG( p );
        break;

      case GXV_GLYPHOFFSET_LONG:
        glyphOffset.l = FT_NEXT_LONG( p );
        break;

      default:
        if ( valid->root->level >= FT_VALIDATE_PARANOID )
          FT_INVALID_FORMAT;
        goto Exit;
      }

      if ( NULL != valid->statetable.entry_validate_func )
        valid->statetable.entry_validate_func( state,
                                               flags,
                                               glyphOffset,
                                               statetable_table,
                                               statetable_limit,
                                               valid );
    }

  Exit:
    *length_p = (FT_UShort)( p - table );

    GXV_EXIT;
  }


  /* =========================== State Table ============================= */

  FT_LOCAL_DEF( void )
  gxv_StateTable_subtable_setup( FT_UShort      table_size,
                                 FT_UShort      classTable,
                                 FT_UShort      stateArray,
                                 FT_UShort      entryTable,
                                 FT_UShort*     classTable_length_p,
                                 FT_UShort*     stateArray_length_p,
                                 FT_UShort*     entryTable_length_p,
                                 GXV_Validator  valid )
  {
    FT_UShort   o[3];
    FT_UShort*  l[3];
    FT_UShort   buff[4];


    o[0] = classTable;
    o[1] = stateArray;
    o[2] = entryTable;
    l[0] = classTable_length_p;
    l[1] = stateArray_length_p;
    l[2] = entryTable_length_p;

    gxv_set_length_by_ushort_offset( o, l, buff, 3, table_size, valid );
  }


  FT_LOCAL_DEF( void )
  gxv_StateTable_validate( FT_Bytes       table,
                           FT_Bytes       limit,
                           GXV_Validator  valid )
  {
    FT_UShort   stateSize;
    FT_UShort   classTable;     /* offset to Class(Sub)Table */
    FT_UShort   stateArray;     /* offset to StateArray */
    FT_UShort   entryTable;     /* offset to EntryTable */

    FT_UShort   classTable_length;
    FT_UShort   stateArray_length;
    FT_UShort   entryTable_length;
    FT_Byte     maxClassID;
    FT_Byte     maxState;
    FT_Byte     maxEntry;

    GXV_StateTable_Subtable_Setup_Func  setup_func;

    FT_Bytes    p = table;


    GXV_NAME_ENTER( "StateTable" );

    GXV_TRACE(( "StateTable header\n" ));

    GXV_LIMIT_CHECK( 2 + 2 + 2 + 2 );
    stateSize  = FT_NEXT_USHORT( p );
    classTable = FT_NEXT_USHORT( p );
    stateArray = FT_NEXT_USHORT( p );
    entryTable = FT_NEXT_USHORT( p );

    GXV_TRACE(( "stateSize=0x%04x\n", stateSize ));
    GXV_TRACE(( "offset to classTable=0x%04x\n", classTable ));
    GXV_TRACE(( "offset to stateArray=0x%04x\n", stateArray ));
    GXV_TRACE(( "offset to entryTable=0x%04x\n", entryTable ));

    if ( stateSize > 0xFF )
      FT_INVALID_DATA;

    if ( valid->statetable.optdata_load_func != NULL )
      valid->statetable.optdata_load_func( p, limit, valid );

    if ( valid->statetable.subtable_setup_func != NULL)
      setup_func = valid->statetable.subtable_setup_func;
    else
      setup_func = gxv_StateTable_subtable_setup;

    setup_func( (FT_UShort)( limit - table ),
                classTable,
                stateArray,
                entryTable,
                &classTable_length,
                &stateArray_length,
                &entryTable_length,
                valid );

    GXV_TRACE(( "StateTable Subtables\n" ));

    if ( classTable != 0 )
      gxv_ClassTable_validate( table + classTable,
                               &classTable_length,
                               stateSize,
                               &maxClassID,
                               valid );
    else
      maxClassID = (FT_Byte)( stateSize - 1 );

    if ( stateArray != 0 )
      gxv_StateArray_validate( table + stateArray,
                               &stateArray_length,
                               maxClassID,
                               stateSize,
                               &maxState,
                               &maxEntry,
                               valid );
    else
    {
      maxState = 1;     /* 0:start of text, 1:start of line are predefined */
      maxEntry = 0;
    }

    if ( maxEntry > 0 && entryTable == 0 )
      FT_INVALID_OFFSET;

    if ( entryTable != 0 )
      gxv_EntryTable_validate( table + entryTable,
                               &entryTable_length,
                               maxEntry,
                               stateArray,
                               stateArray_length,
                               maxClassID,
                               table,
                               limit,
                               valid );

    GXV_EXIT;