cffgload.c.svn-base

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      /********************************************************************/
      /*                                                                  */
      /* Decode operator or operand                                       */
      /*                                                                  */
      v = *ip++;
      if ( v >= 32 || v == 28 )
      {
        FT_Int    shift = 16;
        FT_Int32  val;


        /* this is an operand, push it on the stack */
        if ( v == 28 )
        {
          if ( ip + 1 >= limit )
            goto Syntax_Error;
          val = (FT_Short)( ( (FT_Short)ip[0] << 8 ) | ip[1] );
          ip += 2;
        }
        else if ( v < 247 )
          val = (FT_Long)v - 139;
        else if ( v < 251 )
        {
          if ( ip >= limit )
            goto Syntax_Error;
          val = ( (FT_Long)v - 247 ) * 256 + *ip++ + 108;
        }
        else if ( v < 255 )
        {
          if ( ip >= limit )
            goto Syntax_Error;
          val = -( (FT_Long)v - 251 ) * 256 - *ip++ - 108;
        }
        else
        {
          if ( ip + 3 >= limit )
            goto Syntax_Error;
          val = ( (FT_Int32)ip[0] << 24 ) |
                ( (FT_Int32)ip[1] << 16 ) |
                ( (FT_Int32)ip[2] <<  8 ) |
                            ip[3];
          ip    += 4;
          shift  = 0;
        }
        if ( decoder->top - stack >= CFF_MAX_OPERANDS )
          goto Stack_Overflow;

        val           <<= shift;
        *decoder->top++ = val;

#ifdef FT_DEBUG_LEVEL_TRACE
        if ( !( val & 0xFFFFL ) )
          FT_TRACE4(( " %ld", (FT_Int32)( val >> 16 ) ));
        else
          FT_TRACE4(( " %.2f", val / 65536.0 ));
#endif

      }
      else
      {
        FT_Fixed*  args     = decoder->top;
        FT_Int     num_args = (FT_Int)( args - decoder->stack );
        FT_Int     req_args;


        /* find operator */
        op = cff_op_unknown;

        switch ( v )
        {
        case 1:
          op = cff_op_hstem;
          break;
        case 3:
          op = cff_op_vstem;
          break;
        case 4:
          op = cff_op_vmoveto;
          break;
        case 5:
          op = cff_op_rlineto;
          break;
        case 6:
          op = cff_op_hlineto;
          break;
        case 7:
          op = cff_op_vlineto;
          break;
        case 8:
          op = cff_op_rrcurveto;
          break;
        case 9:
          op = cff_op_closepath;
          break;
        case 10:
          op = cff_op_callsubr;
          break;
        case 11:
          op = cff_op_return;
          break;
        case 12:
          {
            if ( ip >= limit )
              goto Syntax_Error;
            v = *ip++;

            switch ( v )
            {
            case 0:
              op = cff_op_dotsection;
              break;
            case 3:
              op = cff_op_and;
              break;
            case 4:
              op = cff_op_or;
              break;
            case 5:
              op = cff_op_not;
              break;
            case 8:
              op = cff_op_store;
              break;
            case 9:
              op = cff_op_abs;
              break;
            case 10:
              op = cff_op_add;
              break;
            case 11:
              op = cff_op_sub;
              break;
            case 12:
              op = cff_op_div;
              break;
            case 13:
              op = cff_op_load;
              break;
            case 14:
              op = cff_op_neg;
              break;
            case 15:
              op = cff_op_eq;
              break;
            case 18:
              op = cff_op_drop;
              break;
            case 20:
              op = cff_op_put;
              break;
            case 21:
              op = cff_op_get;
              break;
            case 22:
              op = cff_op_ifelse;
              break;
            case 23:
              op = cff_op_random;
              break;
            case 24:
              op = cff_op_mul;
              break;
            case 26:
              op = cff_op_sqrt;
              break;
            case 27:
              op = cff_op_dup;
              break;
            case 28:
              op = cff_op_exch;
              break;
            case 29:
              op = cff_op_index;
              break;
            case 30:
              op = cff_op_roll;
              break;
            case 34:
              op = cff_op_hflex;
              break;
            case 35:
              op = cff_op_flex;
              break;
            case 36:
              op = cff_op_hflex1;
              break;
            case 37:
              op = cff_op_flex1;
              break;
            default:
              /* decrement ip for syntax error message */
              ip--;
            }
          }
          break;
        case 13:
          op = cff_op_hsbw;
          break;
        case 14:
          op = cff_op_endchar;
          break;
        case 16:
          op = cff_op_blend;
          break;
        case 18:
          op = cff_op_hstemhm;
          break;
        case 19:
          op = cff_op_hintmask;
          break;
        case 20:
          op = cff_op_cntrmask;
          break;
        case 21:
          op = cff_op_rmoveto;
          break;
        case 22:
          op = cff_op_hmoveto;
          break;
        case 23:
          op = cff_op_vstemhm;
          break;
        case 24:
          op = cff_op_rcurveline;
          break;
        case 25:
          op = cff_op_rlinecurve;
          break;
        case 26:
          op = cff_op_vvcurveto;
          break;
        case 27:
          op = cff_op_hhcurveto;
          break;
        case 29:
          op = cff_op_callgsubr;
          break;
        case 30:
          op = cff_op_vhcurveto;
          break;
        case 31:
          op = cff_op_hvcurveto;
          break;
        default:
          ;
        }
        if ( op == cff_op_unknown )
          goto Syntax_Error;

        /* check arguments */
        req_args = cff_argument_counts[op];
        if ( req_args & CFF_COUNT_CHECK_WIDTH )
        {
          args = stack;

          if ( num_args > 0 && decoder->read_width )
          {
            /* If `nominal_width' is non-zero, the number is really a      */
            /* difference against `nominal_width'.  Else, the number here  */
            /* is truly a width, not a difference against `nominal_width'. */
            /* If the font does not set `nominal_width', then              */
            /* `nominal_width' defaults to zero, and so we can set         */
            /* `glyph_width' to `nominal_width' plus number on the stack   */
            /* -- for either case.                                         */

            FT_Int  set_width_ok;


            switch ( op )
            {
            case cff_op_hmoveto:
            case cff_op_vmoveto:
              set_width_ok = num_args & 2;
              break;

            case cff_op_hstem:
            case cff_op_vstem:
            case cff_op_hstemhm:
            case cff_op_vstemhm:
            case cff_op_rmoveto:
            case cff_op_hintmask:
            case cff_op_cntrmask:
              set_width_ok = num_args & 1;
              break;

            case cff_op_endchar:
              /* If there is a width specified for endchar, we either have */
              /* 1 argument or 5 arguments.  We like to argue.             */
              set_width_ok = ( ( num_args == 5 ) || ( num_args == 1 ) );
              break;

            default:
              set_width_ok = 0;
              break;
            }

            if ( set_width_ok )
            {
              decoder->glyph_width = decoder->nominal_width +
                                       ( stack[0] >> 16 );

              /* Consumed an argument. */
              num_args--;
              args++;
            }
          }

          decoder->read_width = 0;
          req_args            = 0;
        }

        req_args &= 0x000F;
        if ( num_args < req_args )
          goto Stack_Underflow;
        args     -= req_args;
        num_args -= req_args;

        switch ( op )
        {
        case cff_op_hstem:
        case cff_op_vstem:
        case cff_op_hstemhm:
        case cff_op_vstemhm:
          /* the number of arguments is always even here */
          FT_TRACE4(( op == cff_op_hstem   ? " hstem"   :
                    ( op == cff_op_vstem   ? " vstem"   :
                    ( op == cff_op_hstemhm ? " hstemhm" : " vstemhm" ) ) ));

          if ( hinter )
            hinter->stems( hinter->hints,
                           ( op == cff_op_hstem || op == cff_op_hstemhm ),
                           num_args / 2,
                           args );

          decoder->num_hints += num_args / 2;
          args = stack;
          break;

        case cff_op_hintmask:
        case cff_op_cntrmask:
          FT_TRACE4(( op == cff_op_hintmask ? " hintmask" : " cntrmask" ));

          /* implement vstem when needed --                        */
          /* the specification doesn't say it, but this also works */
          /* with the 'cntrmask' operator                          */
          /*                                                       */
          if ( num_args > 0 )
          {
            if ( hinter )
              hinter->stems( hinter->hints,
                             0,
                             num_args / 2,
                             args );

            decoder->num_hints += num_args / 2;
          }

          if ( hinter )
          {
            if ( op == cff_op_hintmask )
              hinter->hintmask( hinter->hints,
                                builder->current->n_points,
                                decoder->num_hints,
                                ip );
            else
              hinter->counter( hinter->hints,
                               decoder->num_hints,
                               ip );
          }

#ifdef FT_DEBUG_LEVEL_TRACE
          {
            FT_UInt maskbyte;


            FT_TRACE4(( " " ));

            for ( maskbyte = 0;
                  maskbyte < (FT_UInt)(( decoder->num_hints + 7 ) >> 3);
                  maskbyte++, ip++ )
              FT_TRACE4(( "0x%02X", *ip ));
          }
#else
          ip += ( decoder->num_hints + 7 ) >> 3;
#endif
          if ( ip >= limit )
            goto Syntax_Error;
          args = stack;
          break;

        case cff_op_rmoveto:
          FT_TRACE4(( " rmoveto" ));

          cff_builder_close_contour( builder );
          builder->path_begun = 0;
          x   += args[0];
          y   += args[1];
          args = stack;
          break;

        case cff_op_vmoveto:
          FT_TRACE4(( " vmoveto" ));

          cff_builder_close_contour( builder );
          builder->path_begun = 0;
          y   += args[0];
          args = stack;
          break;

        case cff_op_hmoveto:
          FT_TRACE4(( " hmoveto" ));

          cff_builder_close_contour( builder );
          builder->path_begun = 0;
          x   += args[0];
          args = stack;
          break;

        case cff_op_rlineto:
          FT_TRACE4(( " rlineto" ));

          if ( cff_builder_start_point ( builder, x, y ) ||
               check_points( builder, num_args / 2 )     )
            goto Fail;

          if ( num_args < 2 || num_args & 1 )
            goto Stack_Underflow;

          args = stack;
          while ( args < decoder->top )
          {
            x += args[0];
            y += args[1];
            cff_builder_add_point( builder, x, y, 1 );
            args += 2;
          }
          args = stack;
          break;

        case cff_op_hlineto:
        case cff_op_vlineto:
          {
            FT_Int  phase = ( op == cff_op_hlineto );