/***************************************************************************/

/*                                                                         */

/*  gxvmort1.c                                                             */

/*                                                                         */

/*    TrueTypeGX/AAT mort table validation                                 */

/*    body for type1 (Contextual Substitution) subtable.                   */

/*                                                                         */

/*  Copyright 2005, 2007 by suzuki toshiya, Masatake YAMATO, Red Hat K.K., */

/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */

/*                                                                         */

/*  This file is part of the FreeType project, and may only be used,       */

/*  modified, and distributed under the terms of the FreeType project      */

/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */

/*  this file you indicate that you have read the license and              */

/*  understand and accept it fully.                                        */

/*                                                                         */

/***************************************************************************/

/***************************************************************************/

/*                                                                         */

/* gxvalid is derived from both gxlayout module and otvalid module.        */

/* Development of gxlayout is supported by the Information-technology      */

/* Promotion Agency(IPA), Japan.                                           */

/*                                                                         */

/***************************************************************************/

#include "gxvmort.h"

  /*************************************************************************/

  /*                                                                       */

  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */

  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */

  /* messages during execution.                                            */

  /*                                                                       */

#undef  FT_COMPONENT

#define FT_COMPONENT  trace_gxvmort

  typedef struct  GXV_mort_subtable_type1_StateOptRec_

  {

    FT_UShort  substitutionTable;

    FT_UShort  substitutionTable_length;

  }  GXV_mort_subtable_type1_StateOptRec,

    *GXV_mort_subtable_type1_StateOptRecData;

#define GXV_MORT_SUBTABLE_TYPE1_HEADER_SIZE \

          ( GXV_STATETABLE_HEADER_SIZE + 2 )

  static void

  gxv_mort_subtable_type1_substitutionTable_load( FT_Bytes       table,

                                                  FT_Bytes       limit,

                                                  GXV_Validator  valid )

  {

    FT_Bytes  p = table;

    GXV_mort_subtable_type1_StateOptRecData  optdata =

      (GXV_mort_subtable_type1_StateOptRecData)valid->statetable.optdata;

    GXV_LIMIT_CHECK( 2 );

    optdata->substitutionTable = FT_NEXT_USHORT( p );

  }

  static void

  gxv_mort_subtable_type1_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[4];

    FT_UShort  *l[4];

    FT_UShort  buff[5];

    GXV_mort_subtable_type1_StateOptRecData  optdata =

      (GXV_mort_subtable_type1_StateOptRecData)valid->statetable.optdata;

    o[0] = classTable;

    o[1] = stateArray;

    o[2] = entryTable;

    o[3] = optdata->substitutionTable;

    l[0] = classTable_length_p;

    l[1] = stateArray_length_p;

    l[2] = entryTable_length_p;

    l[3] = &( optdata->substitutionTable_length );

    gxv_set_length_by_ushort_offset( o, l, buff, 4, table_size, valid );

  }

  static void

  gxv_mort_subtable_type1_offset_to_subst_validate(

    FT_Short          wordOffset,

    const FT_String*  tag,

    FT_Byte           state,

    GXV_Validator     valid )

  {

    FT_UShort  substTable;

    FT_UShort  substTable_limit;

    FT_UShort  min_gid;

    FT_UShort  max_gid;

    FT_UNUSED( tag );

    FT_UNUSED( state );

    substTable =

      ((GXV_mort_subtable_type1_StateOptRec *)

       (valid->statetable.optdata))->substitutionTable;

    substTable_limit =

      (FT_UShort)( substTable +

                   ((GXV_mort_subtable_type1_StateOptRec *)

                    (valid->statetable.optdata))->substitutionTable_length );

    min_gid = (FT_UShort)( ( substTable       - wordOffset * 2 ) / 2 );

    max_gid = (FT_UShort)( ( substTable_limit - wordOffset * 2 ) / 2 );

    max_gid = (FT_UShort)( FT_MAX( max_gid, valid->face->num_glyphs ) );

    /* XXX: check range? */

    /* TODO: min_gid & max_gid comparison with ClassTable contents */

  }

  static void

  gxv_mort_subtable_type1_entry_validate(

    FT_Byte                         state,

    FT_UShort                       flags,

    GXV_StateTable_GlyphOffsetCPtr  glyphOffset_p,

    FT_Bytes                        table,

    FT_Bytes                        limit,

    GXV_Validator                   valid )

  {

    FT_UShort  setMark;

    FT_UShort  dontAdvance;

    FT_UShort  reserved;

    FT_Short   markOffset;

    FT_Short   currentOffset;

    FT_UNUSED( table );

    FT_UNUSED( limit );

    setMark       = (FT_UShort)(   flags >> 15            );

    dontAdvance   = (FT_UShort)( ( flags >> 14 ) & 1      );

    reserved      = (FT_Short)(    flags         & 0x3FFF );

    markOffset    = (FT_Short)( glyphOffset_p->ul >> 16 );

    currentOffset = (FT_Short)( glyphOffset_p->ul       );

    if ( 0 < reserved )

    {

      GXV_TRACE(( " non-zero bits found in reserved range\n" ));

      if ( valid->root->level >= FT_VALIDATE_PARANOID )

        FT_INVALID_DATA;

    }

    gxv_mort_subtable_type1_offset_to_subst_validate( markOffset,

                                                      "markOffset",

                                                      state,

                                                      valid );

    gxv_mort_subtable_type1_offset_to_subst_validate( currentOffset,

                                                      "currentOffset",

                                                      state,

                                                      valid );

  }

  static void

  gxv_mort_subtable_type1_substTable_validate( FT_Bytes       table,

                                               FT_Bytes       limit,

                                               GXV_Validator  valid )

  {

    FT_Bytes   p = table;

    FT_UShort  num_gids = (FT_UShort)(

                 ((GXV_mort_subtable_type1_StateOptRec *)

                  (valid->statetable.optdata))->substitutionTable_length / 2 );

    FT_UShort  i;

    GXV_NAME_ENTER( "validating contents of substitutionTable" );

    for ( i = 0; i < num_gids ; i ++ )

    {

      FT_UShort  dst_gid;

      GXV_LIMIT_CHECK( 2 );

      dst_gid = FT_NEXT_USHORT( p );

      if ( dst_gid >= 0xFFFFU )

        continue;

      if ( dst_gid > valid->face->num_glyphs )

      {

        GXV_TRACE(( "substTable include too large gid[%d]=%d >"

                    " max defined gid #%d\n",

                    i, dst_gid, valid->face->num_glyphs ));

        if ( valid->root->level >= FT_VALIDATE_PARANOID )

          FT_INVALID_GLYPH_ID;

      }

    }

    GXV_EXIT;

  }

  /*

   * subtable for Contextual glyph substitution is a modified StateTable.

   * In addition to classTable, stateArray, and entryTable, the field

   * `substitutionTable' is added.

   */

  FT_LOCAL_DEF( void )

  gxv_mort_subtable_type1_validate( FT_Bytes       table,

                                    FT_Bytes       limit,

                                    GXV_Validator  valid )

  {

    FT_Bytes  p = table;

    GXV_mort_subtable_type1_StateOptRec  st_rec;

    GXV_NAME_ENTER( "mort chain subtable type1 (Contextual Glyph Subst)" );

    GXV_LIMIT_CHECK( GXV_MORT_SUBTABLE_TYPE1_HEADER_SIZE );

    valid->statetable.optdata =

      &st_rec;

    valid->statetable.optdata_load_func =

      gxv_mort_subtable_type1_substitutionTable_load;

    valid->statetable.subtable_setup_func =

      gxv_mort_subtable_type1_subtable_setup;

    valid->statetable.entry_glyphoffset_fmt =

      GXV_GLYPHOFFSET_ULONG;

    valid->statetable.entry_validate_func =

      gxv_mort_subtable_type1_entry_validate;

    gxv_StateTable_validate( p, limit, valid );

    gxv_mort_subtable_type1_substTable_validate(

      table + st_rec.substitutionTable,

      table + st_rec.substitutionTable + st_rec.substitutionTable_length,

      valid );

    GXV_EXIT;

  }

/* END */