reactos/lib/3rdparty/freetype/src/gxvalid/gxvmort1.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  gxvmort1.c                                                             */
   4 /*                                                                         */
   5 /*    TrueTypeGX/AAT mort table validation                                 */
   6 /*    body for type1 (Contextual Substitution) subtable.                   */
   7 /*                                                                         */
   8 /*  Copyright 2005, 2007 by suzuki toshiya, Masatake YAMATO, Red Hat K.K., */
   9 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
  10 /*                                                                         */
  11 /*  This file is part of the FreeType project, and may only be used,       */
  12 /*  modified, and distributed under the terms of the FreeType project      */
  13 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  14 /*  this file you indicate that you have read the license and              */
  15 /*  understand and accept it fully.                                        */
  16 /*                                                                         */
  17 /***************************************************************************/
  18
  19 /***************************************************************************/
  20 /*                                                                         */
  21 /* gxvalid is derived from both gxlayout module and otvalid module.        */
  22 /* Development of gxlayout is supported by the Information-technology      */
  23 /* Promotion Agency(IPA), Japan.                                           */
  24 /*                                                                         */
  25 /***************************************************************************/
  26
  27
  28 #include "gxvmort.h"
  29
  30
  31   /*************************************************************************/
  32   /*                                                                       */
  33   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  34   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  35   /* messages during execution.                                            */
  36   /*                                                                       */
  37 #undef  FT_COMPONENT
  38 #define FT_COMPONENT  trace_gxvmort
  39
  40
  41   typedef struct  GXV_mort_subtable_type1_StateOptRec_
  42   {
  43     FT_UShort  substitutionTable;
  44     FT_UShort  substitutionTable_length;
  45
  46   }  GXV_mort_subtable_type1_StateOptRec,
  47     *GXV_mort_subtable_type1_StateOptRecData;
  48
  49 #define GXV_MORT_SUBTABLE_TYPE1_HEADER_SIZE \
  50           ( GXV_STATETABLE_HEADER_SIZE + 2 )
  51
  52
  53   static void
  54   gxv_mort_subtable_type1_substitutionTable_load( FT_Bytes       table,
  55                                                   FT_Bytes       limit,
  56                                                   GXV_Validator  valid )
  57   {
  58     FT_Bytes  p = table;
  59
  60     GXV_mort_subtable_type1_StateOptRecData  optdata =
  61       (GXV_mort_subtable_type1_StateOptRecData)valid->statetable.optdata;
  62
  63
  64     GXV_LIMIT_CHECK( 2 );
  65     optdata->substitutionTable = FT_NEXT_USHORT( p );
  66   }
  67
  68
  69   static void
  70   gxv_mort_subtable_type1_subtable_setup( FT_UShort      table_size,
  71                                           FT_UShort      classTable,
  72                                           FT_UShort      stateArray,
  73                                           FT_UShort      entryTable,
  74                                           FT_UShort*     classTable_length_p,
  75                                           FT_UShort*     stateArray_length_p,
  76                                           FT_UShort*     entryTable_length_p,
  77                                           GXV_Validator  valid )
  78   {
  79     FT_UShort  o[4];
  80     FT_UShort  *l[4];
  81     FT_UShort  buff[5];
  82
  83     GXV_mort_subtable_type1_StateOptRecData  optdata =
  84       (GXV_mort_subtable_type1_StateOptRecData)valid->statetable.optdata;
  85
  86
  87     o[0] = classTable;
  88     o[1] = stateArray;
  89     o[2] = entryTable;
  90     o[3] = optdata->substitutionTable;
  91     l[0] = classTable_length_p;
  92     l[1] = stateArray_length_p;
  93     l[2] = entryTable_length_p;
  94     l[3] = &( optdata->substitutionTable_length );
  95
  96     gxv_set_length_by_ushort_offset( o, l, buff, 4, table_size, valid );
  97   }
  98
  99
 100   static void
 101   gxv_mort_subtable_type1_offset_to_subst_validate(
 102     FT_Short          wordOffset,
 103     const FT_String*  tag,
 104     FT_Byte           state,
 105     GXV_Validator     valid )
 106   {
 107     FT_UShort  substTable;
 108     FT_UShort  substTable_limit;
 109     FT_UShort  min_gid;
 110     FT_UShort  max_gid;
 111
 112     FT_UNUSED( tag );
 113     FT_UNUSED( state );
 114
 115
 116     substTable =
 117       ((GXV_mort_subtable_type1_StateOptRec *)
 118        (valid->statetable.optdata))->substitutionTable;
 119     substTable_limit =
 120       (FT_UShort)( substTable +
 121                    ((GXV_mort_subtable_type1_StateOptRec *)
 122                     (valid->statetable.optdata))->substitutionTable_length );
 123
 124     min_gid = (FT_UShort)( ( substTable       - wordOffset * 2 ) / 2 );
 125     max_gid = (FT_UShort)( ( substTable_limit - wordOffset * 2 ) / 2 );
 126     max_gid = (FT_UShort)( FT_MAX( max_gid, valid->face->num_glyphs ) );
 127
 128     /* XXX: check range? */
 129
 130     /* TODO: min_gid & max_gid comparison with ClassTable contents */
 131   }
 132
 133
 134   static void
 135   gxv_mort_subtable_type1_entry_validate(
 136     FT_Byte                         state,
 137     FT_UShort                       flags,
 138     GXV_StateTable_GlyphOffsetCPtr  glyphOffset_p,
 139     FT_Bytes                        table,
 140     FT_Bytes                        limit,
 141     GXV_Validator                   valid )
 142   {
 143     FT_UShort  setMark;
 144     FT_UShort  dontAdvance;
 145     FT_UShort  reserved;
 146     FT_Short   markOffset;
 147     FT_Short   currentOffset;
 148
 149     FT_UNUSED( table );
 150     FT_UNUSED( limit );
 151
 152
 153     setMark       = (FT_UShort)(   flags >> 15            );
 154     dontAdvance   = (FT_UShort)( ( flags >> 14 ) & 1      );
 155     reserved      = (FT_Short)(    flags         & 0x3FFF );
 156
 157     markOffset    = (FT_Short)( glyphOffset_p->ul >> 16 );
 158     currentOffset = (FT_Short)( glyphOffset_p->ul       );
 159
 160     if ( 0 < reserved )
 161     {
 162       GXV_TRACE(( " non-zero bits found in reserved range\n" ));
 163       if ( valid->root->level >= FT_VALIDATE_PARANOID )
 164         FT_INVALID_DATA;
 165     }
 166
 167     gxv_mort_subtable_type1_offset_to_subst_validate( markOffset,
 168                                                       "markOffset",
 169                                                       state,
 170                                                       valid );
 171
 172     gxv_mort_subtable_type1_offset_to_subst_validate( currentOffset,
 173                                                       "currentOffset",
 174                                                       state,
 175                                                       valid );
 176   }
 177
 178
 179   static void
 180   gxv_mort_subtable_type1_substTable_validate( FT_Bytes       table,
 181                                                FT_Bytes       limit,
 182                                                GXV_Validator  valid )
 183   {
 184     FT_Bytes   p = table;
 185     FT_UShort  num_gids = (FT_UShort)(
 186                  ((GXV_mort_subtable_type1_StateOptRec *)
 187                   (valid->statetable.optdata))->substitutionTable_length / 2 );
 188     FT_UShort  i;
 189
 190
 191     GXV_NAME_ENTER( "validating contents of substitutionTable" );
 192     for ( i = 0; i < num_gids ; i ++ )
 193     {
 194       FT_UShort  dst_gid;
 195
 196
 197       GXV_LIMIT_CHECK( 2 );
 198       dst_gid = FT_NEXT_USHORT( p );
 199
 200       if ( dst_gid >= 0xFFFFU )
 201         continue;
 202
 203       if ( dst_gid > valid->face->num_glyphs )
 204       {
 205         GXV_TRACE(( "substTable include too large gid[%d]=%d >"
 206                     " max defined gid #%d\n",
 207                     i, dst_gid, valid->face->num_glyphs ));
 208         if ( valid->root->level >= FT_VALIDATE_PARANOID )
 209           FT_INVALID_GLYPH_ID;
 210       }
 211     }
 212
 213     GXV_EXIT;
 214   }
 215
 216
 217   /*
 218    * subtable for Contextual glyph substitution is a modified StateTable.
 219    * In addition to classTable, stateArray, and entryTable, the field
 220    * `substitutionTable' is added.
 221    */
 222   FT_LOCAL_DEF( void )
 223   gxv_mort_subtable_type1_validate( FT_Bytes       table,
 224                                     FT_Bytes       limit,
 225                                     GXV_Validator  valid )
 226   {
 227     FT_Bytes  p = table;
 228
 229     GXV_mort_subtable_type1_StateOptRec  st_rec;
 230
 231
 232     GXV_NAME_ENTER( "mort chain subtable type1 (Contextual Glyph Subst)" );
 233
 234     GXV_LIMIT_CHECK( GXV_MORT_SUBTABLE_TYPE1_HEADER_SIZE );
 235
 236     valid->statetable.optdata =
 237       &st_rec;
 238     valid->statetable.optdata_load_func =
 239       gxv_mort_subtable_type1_substitutionTable_load;
 240     valid->statetable.subtable_setup_func =
 241       gxv_mort_subtable_type1_subtable_setup;
 242     valid->statetable.entry_glyphoffset_fmt =
 243       GXV_GLYPHOFFSET_ULONG;
 244     valid->statetable.entry_validate_func =
 245
 246       gxv_mort_subtable_type1_entry_validate;
 247     gxv_StateTable_validate( p, limit, valid );
 248
 249     gxv_mort_subtable_type1_substTable_validate(
 250       table + st_rec.substitutionTable,
 251       table + st_rec.substitutionTable + st_rec.substitutionTable_length,
 252       valid );
 253
 254     GXV_EXIT;
 255   }
 256
 257
 258 /* END */