reactos/dll/3rdparty/freetype/src/gxvalid/gxvmort2.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  gxvmort2.c                                                             */
   4 /*                                                                         */
   5 /*    TrueTypeGX/AAT mort table validation                                 */
   6 /*    body for type2 (Ligature Substitution) subtable.                     */
   7 /*                                                                         */
   8 /*  Copyright 2005 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_type2_StateOptRec_
  42   {
  43     FT_UShort  ligActionTable;
  44     FT_UShort  componentTable;
  45     FT_UShort  ligatureTable;
  46     FT_UShort  ligActionTable_length;
  47     FT_UShort  componentTable_length;
  48     FT_UShort  ligatureTable_length;
  49
  50   }  GXV_mort_subtable_type2_StateOptRec,
  51     *GXV_mort_subtable_type2_StateOptRecData;
  52
  53 #define GXV_MORT_SUBTABLE_TYPE2_HEADER_SIZE \
  54           ( GXV_STATETABLE_HEADER_SIZE + 2 + 2 + 2 )
  55
  56
  57   static void
  58   gxv_mort_subtable_type2_opttable_load( FT_Bytes       table,
  59                                          FT_Bytes       limit,
  60                                          GXV_Validator  valid )
  61   {
  62     FT_Bytes p = table;
  63     GXV_mort_subtable_type2_StateOptRecData  optdata =
  64       (GXV_mort_subtable_type2_StateOptRecData)valid->statetable.optdata;
  65
  66
  67     GXV_LIMIT_CHECK( 2 + 2 + 2 );
  68     optdata->ligActionTable = FT_NEXT_USHORT( p );
  69     optdata->componentTable = FT_NEXT_USHORT( p );
  70     optdata->ligatureTable  = FT_NEXT_USHORT( p );
  71
  72     GXV_TRACE(( "offset to ligActionTable=0x%04x\n",
  73                 optdata->ligActionTable ));
  74     GXV_TRACE(( "offset to componentTable=0x%04x\n",
  75                 optdata->componentTable ));
  76     GXV_TRACE(( "offset to ligatureTable=0x%04x\n",
  77                 optdata->ligatureTable ));
  78   }
  79
  80
  81   static void
  82   gxv_mort_subtable_type2_subtable_setup( FT_UShort      table_size,
  83                                           FT_UShort      classTable,
  84                                           FT_UShort      stateArray,
  85                                           FT_UShort      entryTable,
  86                                           FT_UShort      *classTable_length_p,
  87                                           FT_UShort      *stateArray_length_p,
  88                                           FT_UShort      *entryTable_length_p,
  89                                           GXV_Validator  valid )
  90   {
  91     FT_UShort  o[6];
  92     FT_UShort  *l[6];
  93     FT_UShort  buff[7];
  94
  95     GXV_mort_subtable_type2_StateOptRecData  optdata =
  96       (GXV_mort_subtable_type2_StateOptRecData)valid->statetable.optdata;
  97
  98
  99     GXV_NAME_ENTER( "subtable boundaries setup" );
 100
 101     o[0] = classTable;
 102     o[1] = stateArray;
 103     o[2] = entryTable;
 104     o[3] = optdata->ligActionTable;
 105     o[4] = optdata->componentTable;
 106     o[5] = optdata->ligatureTable;
 107     l[0] = classTable_length_p;
 108     l[1] = stateArray_length_p;
 109     l[2] = entryTable_length_p;
 110     l[3] = &(optdata->ligActionTable_length);
 111     l[4] = &(optdata->componentTable_length);
 112     l[5] = &(optdata->ligatureTable_length);
 113
 114     gxv_set_length_by_ushort_offset( o, l, buff, 6, table_size, valid );
 115
 116     GXV_TRACE(( "classTable: offset=0x%04x length=0x%04x\n",
 117                 classTable, *classTable_length_p ));
 118     GXV_TRACE(( "stateArray: offset=0x%04x length=0x%04x\n",
 119                 stateArray, *stateArray_length_p ));
 120     GXV_TRACE(( "entryTable: offset=0x%04x length=0x%04x\n",
 121                 entryTable, *entryTable_length_p ));
 122     GXV_TRACE(( "ligActionTable: offset=0x%04x length=0x%04x\n",
 123                 optdata->ligActionTable,
 124                 optdata->ligActionTable_length ));
 125     GXV_TRACE(( "componentTable: offset=0x%04x length=0x%04x\n",
 126                 optdata->componentTable,
 127                 optdata->componentTable_length ));
 128     GXV_TRACE(( "ligatureTable:  offset=0x%04x length=0x%04x\n",
 129                 optdata->ligatureTable,
 130                 optdata->ligatureTable_length ));
 131
 132     GXV_EXIT;
 133   }
 134
 135
 136   static void
 137   gxv_mort_subtable_type2_ligActionOffset_validate(
 138     FT_Bytes       table,
 139     FT_UShort      ligActionOffset,
 140     GXV_Validator  valid )
 141   {
 142     /* access ligActionTable */
 143     GXV_mort_subtable_type2_StateOptRecData  optdata =
 144       (GXV_mort_subtable_type2_StateOptRecData)valid->statetable.optdata;
 145
 146     FT_Bytes lat_base  = table + optdata->ligActionTable;
 147     FT_Bytes p         = table + ligActionOffset;
 148     FT_Bytes lat_limit = lat_base + optdata->ligActionTable;
 149
 150
 151     GXV_32BIT_ALIGNMENT_VALIDATE( ligActionOffset );
 152     if ( p < lat_base )
 153     {
 154       GXV_TRACE(( "too short offset 0x%04x: p < lat_base (%d byte rewind)\n",
 155                   ligActionOffset, lat_base - p ));
 156
 157       /* FontValidator, ftxvalidator, ftxdumperfuser warn but continue */
 158       if ( valid->root->level >= FT_VALIDATE_PARANOID )
 159         FT_INVALID_OFFSET;
 160     }
 161     else if ( lat_limit < p )
 162     {
 163       GXV_TRACE(( "too large offset 0x%04x: lat_limit < p (%d byte overrun)\n",
 164                   ligActionOffset, p - lat_limit ));
 165
 166       /* FontValidator, ftxvalidator, ftxdumperfuser warn but continue */
 167       if ( valid->root->level >= FT_VALIDATE_PARANOID )
 168         FT_INVALID_OFFSET;
 169     }
 170     else
 171     {
 172       /* validate entry in ligActionTable */
 173       FT_ULong   lig_action;
 174       FT_UShort  last;
 175       FT_UShort  store;
 176       FT_ULong   offset;
 177
 178
 179       lig_action = FT_NEXT_ULONG( p );
 180       last   = (FT_UShort)( ( lig_action >> 31 ) & 1 );
 181       store  = (FT_UShort)( ( lig_action >> 30 ) & 1 );
 182
 183       offset = lig_action & 0x3FFFFFFFUL;
 184     }
 185   }
 186
 187
 188   static void
 189   gxv_mort_subtable_type2_entry_validate(
 190     FT_Byte                         state,
 191     FT_UShort                       flags,
 192     GXV_StateTable_GlyphOffsetDesc  glyphOffset,
 193     FT_Bytes                        table,
 194     FT_Bytes                        limit,
 195     GXV_Validator                   valid )
 196   {
 197     FT_UShort setComponent;
 198     FT_UShort dontAdvance;
 199     FT_UShort offset;
 200
 201     FT_UNUSED( state );
 202     FT_UNUSED( glyphOffset );
 203     FT_UNUSED( limit );
 204
 205
 206     setComponent = (FT_UShort)( ( flags >> 15 ) & 1 );
 207     dontAdvance  = (FT_UShort)( ( flags >> 14 ) & 1 );
 208
 209     offset = (FT_UShort)( flags & 0x3FFFU );
 210
 211     if ( 0 < offset )
 212       gxv_mort_subtable_type2_ligActionOffset_validate( table, offset,
 213                                                         valid );
 214   }
 215
 216
 217   static void
 218   gxv_mort_subtable_type2_ligatureTable_validate( FT_Bytes       table,
 219                                                   GXV_Validator  valid )
 220   {
 221     GXV_mort_subtable_type2_StateOptRecData  optdata =
 222       (GXV_mort_subtable_type2_StateOptRecData)valid->statetable.optdata;
 223
 224     FT_Bytes p     = table + optdata->ligatureTable;
 225     FT_Bytes limit = table + optdata->ligatureTable
 226                            + optdata->ligatureTable_length;
 227
 228
 229     GXV_NAME_ENTER( "mort chain subtable type2 - substitutionTable" );
 230     if ( 0 != optdata->ligatureTable )
 231     {
 232       /* Apple does not give specification of ligatureTable format */
 233       while ( p < limit )
 234       {
 235         FT_UShort  lig_gid;
 236
 237
 238         GXV_LIMIT_CHECK( 2 );
 239         lig_gid = FT_NEXT_USHORT( p );
 240       }
 241     }
 242     GXV_EXIT;
 243   }
 244
 245
 246   FT_LOCAL_DEF( void )
 247   gxv_mort_subtable_type2_validate( FT_Bytes       table,
 248                                     FT_Bytes       limit,
 249                                     GXV_Validator  valid )
 250   {
 251     FT_Bytes  p = table;
 252
 253     GXV_mort_subtable_type2_StateOptRec  lig_rec;
 254
 255
 256     GXV_NAME_ENTER( "mort chain subtable type2 (Ligature Substitution)" );
 257
 258     GXV_LIMIT_CHECK( GXV_MORT_SUBTABLE_TYPE2_HEADER_SIZE );
 259
 260     valid->statetable.optdata =
 261       &lig_rec;
 262     valid->statetable.optdata_load_func =
 263       gxv_mort_subtable_type2_opttable_load;
 264     valid->statetable.subtable_setup_func =
 265       gxv_mort_subtable_type2_subtable_setup;
 266     valid->statetable.entry_glyphoffset_fmt =
 267       GXV_GLYPHOFFSET_NONE;
 268     valid->statetable.entry_validate_func =
 269       gxv_mort_subtable_type2_entry_validate;
 270
 271     gxv_StateTable_validate( p, limit, valid );
 272
 273     p += valid->subtable_length;
 274     gxv_mort_subtable_type2_ligatureTable_validate( table, valid );
 275
 276     valid->subtable_length = p - table;
 277
 278     GXV_EXIT;
 279   }
 280
 281
 282 /* END */