otvgpos.c.svn-base

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    OTV_EXIT;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                     GPOS LOOKUP TYPE 5                        *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /* sets valid->extra2 (1) */

  static void
  otv_MarkLigPos_validate( FT_Bytes       table,
                           OTV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_UInt   PosFormat;


    OTV_NAME_ENTER( "MarkLigPos" );

    OTV_LIMIT_CHECK( 2 );
    PosFormat = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (format %d)\n", PosFormat ));

    switch ( PosFormat )
    {
    case 1:
      valid->extra2 = 1;
      OTV_NEST3( MarkLigPosFormat1, LigatureArray, LigatureAttach );
      OTV_RUN( table, valid );
      break;

    default:
      FT_INVALID_FORMAT;
    }

    OTV_EXIT;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                     GPOS LOOKUP TYPE 6                        *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /* sets valid->extra2 (0) */

  static void
  otv_MarkMarkPos_validate( FT_Bytes       table,
                            OTV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_UInt   PosFormat;


    OTV_NAME_ENTER( "MarkMarkPos" );

    OTV_LIMIT_CHECK( 2 );
    PosFormat = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (format %d)\n", PosFormat ));

    switch ( PosFormat )
    {
    case 1:
      valid->extra2 = 0;
      OTV_NEST2( MarkMarkPosFormat1, Mark2Array );
      OTV_RUN( table, valid );
      break;

    default:
      FT_INVALID_FORMAT;
    }

    OTV_EXIT;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                     GPOS LOOKUP TYPE 7                        *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /* sets valid->extra1 (lookup count) */

  static void
  otv_ContextPos_validate( FT_Bytes       table,
                           OTV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_UInt   PosFormat;


    OTV_NAME_ENTER( "ContextPos" );

    OTV_LIMIT_CHECK( 2 );
    PosFormat = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (format %d)\n", PosFormat ));

    switch ( PosFormat )
    {
    case 1:
      /* no need to check glyph indices/classes used as input for these */
      /* context rules since even invalid glyph indices/classes return  */
      /* meaningful results                                             */

      valid->extra1 = valid->lookup_count;
      OTV_NEST3( ContextPosFormat1, PosRuleSet, PosRule );
      OTV_RUN( table, valid );
      break;

    case 2:
      /* no need to check glyph indices/classes used as input for these */
      /* context rules since even invalid glyph indices/classes return  */
      /* meaningful results                                             */

      OTV_NEST3( ContextPosFormat2, PosClassSet, PosClassRule );
      OTV_RUN( table, valid );
      break;

    case 3:
      OTV_NEST1( ContextPosFormat3 );
      OTV_RUN( table, valid );
      break;

    default:
      FT_INVALID_FORMAT;
    }

    OTV_EXIT;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                     GPOS LOOKUP TYPE 8                        *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /* sets valid->extra1 (lookup count) */

  static void
  otv_ChainContextPos_validate( FT_Bytes       table,
                                OTV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_UInt   PosFormat;


    OTV_NAME_ENTER( "ChainContextPos" );

    OTV_LIMIT_CHECK( 2 );
    PosFormat = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (format %d)\n", PosFormat ));

    switch ( PosFormat )
    {
    case 1:
      /* no need to check glyph indices/classes used as input for these */
      /* context rules since even invalid glyph indices/classes return  */
      /* meaningful results                                             */

      valid->extra1 = valid->lookup_count;
      OTV_NEST3( ChainContextPosFormat1,
                 ChainPosRuleSet, ChainPosRule );
      OTV_RUN( table, valid );
      break;

    case 2:
      /* no need to check glyph indices/classes used as input for these */
      /* context rules since even invalid glyph indices/classes return  */
      /* meaningful results                                             */

      OTV_NEST3( ChainContextPosFormat2,
                 ChainPosClassSet, ChainPosClassRule );
      OTV_RUN( table, valid );
      break;

    case 3:
      OTV_NEST1( ChainContextPosFormat3 );
      OTV_RUN( table, valid );
      break;

    default:
      FT_INVALID_FORMAT;
    }

    OTV_EXIT;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                     GPOS LOOKUP TYPE 9                        *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /* uses valid->type_funcs */

  static void
  otv_ExtensionPos_validate( FT_Bytes       table,
                             OTV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_UInt   PosFormat;


    OTV_NAME_ENTER( "ExtensionPos" );

    OTV_LIMIT_CHECK( 2 );
    PosFormat = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (format %d)\n", PosFormat ));

    switch ( PosFormat )
    {
    case 1:     /* ExtensionPosFormat1 */
      {
        FT_UInt            ExtensionLookupType, ExtensionOffset;
        OTV_Validate_Func  validate;


        OTV_LIMIT_CHECK( 6 );
        ExtensionLookupType = FT_NEXT_USHORT( p );
        ExtensionOffset     = FT_NEXT_ULONG( p );

        if ( ExtensionLookupType == 0 || ExtensionLookupType >= 9 )
          FT_INVALID_DATA;

        validate = valid->type_funcs[ExtensionLookupType - 1];
        validate( table + ExtensionOffset, valid );
      }
      break;

    default:
      FT_INVALID_FORMAT;
    }

    OTV_EXIT;
  }


  static const OTV_Validate_Func  otv_gpos_validate_funcs[9] =
  {
    otv_SinglePos_validate,
    otv_PairPos_validate,
    otv_CursivePos_validate,
    otv_MarkBasePos_validate,
    otv_MarkLigPos_validate,
    otv_MarkMarkPos_validate,
    otv_ContextPos_validate,
    otv_ChainContextPos_validate,
    otv_ExtensionPos_validate
  };


  /* sets valid->type_count */
  /* sets valid->type_funcs */

  FT_LOCAL_DEF( void )
  otv_GPOS_subtable_validate( FT_Bytes       table,
                              OTV_Validator  valid )
  {
    valid->type_count = 9;
    valid->type_funcs = (OTV_Validate_Func*)otv_gpos_validate_funcs;

    otv_Lookup_validate( table, valid );
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                          GPOS TABLE                           *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /* sets valid->glyph_count */

  FT_LOCAL_DEF( void )
  otv_GPOS_validate( FT_Bytes      table,
                     FT_UInt       glyph_count,
                     FT_Validator  ftvalid )
  {
    OTV_ValidatorRec  validrec;
    OTV_Validator     valid = &validrec;
    FT_Bytes          p     = table;
    FT_UInt           ScriptList, FeatureList, LookupList;


    valid->root = ftvalid;

    FT_TRACE3(( "validating GPOS table\n" ));
    OTV_INIT;

    OTV_LIMIT_CHECK( 10 );

    if ( FT_NEXT_ULONG( p ) != 0x10000UL )      /* Version */
      FT_INVALID_FORMAT;

    ScriptList  = FT_NEXT_USHORT( p );
    FeatureList = FT_NEXT_USHORT( p );
    LookupList  = FT_NEXT_USHORT( p );

    valid->type_count  = 9;
    valid->type_funcs  = (OTV_Validate_Func*)otv_gpos_validate_funcs;
    valid->glyph_count = glyph_count;

    otv_LookupList_validate( table + LookupList,
                             valid );
    otv_FeatureList_validate( table + FeatureList, table + LookupList,
                              valid );
    otv_ScriptList_validate( table + ScriptList, table + FeatureList,
                             valid );

    FT_TRACE4(( "\n" ));
  }


/* END */