reactos/lib/3rdparty/freetype/src/gxvalid/gxvmorx2.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  gxvmorx2.c                                                             */
   4 /*                                                                         */
   5 /*    TrueTypeGX/AAT morx table validation                                 */
   6 /*    body for type2 (Ligature Substitution) subtable.                     */
   7 /*                                                                         */
   8 /*  Copyright 2005-2016 by                                                 */
   9 /*  suzuki toshiya, Masatake YAMATO, Red Hat K.K.,                         */
  10 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
  11 /*                                                                         */
  12 /*  This file is part of the FreeType project, and may only be used,       */
  13 /*  modified, and distributed under the terms of the FreeType project      */
  14 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  15 /*  this file you indicate that you have read the license and              */
  16 /*  understand and accept it fully.                                        */
  17 /*                                                                         */
  18 /***************************************************************************/
  19
  20 /***************************************************************************/
  21 /*                                                                         */
  22 /* gxvalid is derived from both gxlayout module and otvalid module.        */
  23 /* Development of gxlayout is supported by the Information-technology      */
  24 /* Promotion Agency(IPA), Japan.                                           */
  25 /*                                                                         */
  26 /***************************************************************************/
  27
  28
  29 #include "gxvmorx.h"
  30
  31
  32   /*************************************************************************/
  33   /*                                                                       */
  34   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  35   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  36   /* messages during execution.                                            */
  37   /*                                                                       */
  38 #undef  FT_COMPONENT
  39 #define FT_COMPONENT  trace_gxvmorx
  40
  41
  42   typedef struct  GXV_morx_subtable_type2_StateOptRec_
  43   {
  44     FT_ULong  ligActionTable;
  45     FT_ULong  componentTable;
  46     FT_ULong  ligatureTable;
  47     FT_ULong  ligActionTable_length;
  48     FT_ULong  componentTable_length;
  49     FT_ULong  ligatureTable_length;
  50
  51   }  GXV_morx_subtable_type2_StateOptRec,
  52     *GXV_morx_subtable_type2_StateOptRecData;
  53
  54
  55 #define GXV_MORX_SUBTABLE_TYPE2_HEADER_SIZE \
  56           ( GXV_XSTATETABLE_HEADER_SIZE + 4 + 4 + 4 )
  57
  58
  59   static void
  60   gxv_morx_subtable_type2_opttable_load( FT_Bytes       table,
  61                                          FT_Bytes       limit,
  62                                          GXV_Validator  gxvalid )
  63   {
  64     FT_Bytes  p = table;
  65
  66     GXV_morx_subtable_type2_StateOptRecData  optdata =
  67       (GXV_morx_subtable_type2_StateOptRecData)gxvalid->xstatetable.optdata;
  68
  69
  70     GXV_LIMIT_CHECK( 4 + 4 + 4 );
  71     optdata->ligActionTable = FT_NEXT_ULONG( p );
  72     optdata->componentTable = FT_NEXT_ULONG( p );
  73     optdata->ligatureTable  = FT_NEXT_ULONG( p );
  74
  75     GXV_TRACE(( "offset to ligActionTable=0x%08x\n",
  76                 optdata->ligActionTable ));
  77     GXV_TRACE(( "offset to componentTable=0x%08x\n",
  78                 optdata->componentTable ));
  79     GXV_TRACE(( "offset to ligatureTable=0x%08x\n",
  80                 optdata->ligatureTable ));
  81   }
  82
  83
  84   static void
  85   gxv_morx_subtable_type2_subtable_setup( FT_ULong       table_size,
  86                                           FT_ULong       classTable,
  87                                           FT_ULong       stateArray,
  88                                           FT_ULong       entryTable,
  89                                           FT_ULong*      classTable_length_p,
  90                                           FT_ULong*      stateArray_length_p,
  91                                           FT_ULong*      entryTable_length_p,
  92                                           GXV_Validator  gxvalid )
  93   {
  94     FT_ULong   o[6];
  95     FT_ULong*  l[6];
  96     FT_ULong   buff[7];
  97
  98     GXV_morx_subtable_type2_StateOptRecData  optdata =
  99       (GXV_morx_subtable_type2_StateOptRecData)gxvalid->xstatetable.optdata;
 100
 101
 102     GXV_NAME_ENTER( "subtable boundaries setup" );
 103
 104     o[0] = classTable;
 105     o[1] = stateArray;
 106     o[2] = entryTable;
 107     o[3] = optdata->ligActionTable;
 108     o[4] = optdata->componentTable;
 109     o[5] = optdata->ligatureTable;
 110     l[0] = classTable_length_p;
 111     l[1] = stateArray_length_p;
 112     l[2] = entryTable_length_p;
 113     l[3] = &(optdata->ligActionTable_length);
 114     l[4] = &(optdata->componentTable_length);
 115     l[5] = &(optdata->ligatureTable_length);
 116
 117     gxv_set_length_by_ulong_offset( o, l, buff, 6, table_size, gxvalid );
 118
 119     GXV_TRACE(( "classTable: offset=0x%08x length=0x%08x\n",
 120                 classTable, *classTable_length_p ));
 121     GXV_TRACE(( "stateArray: offset=0x%08x length=0x%08x\n",
 122                 stateArray, *stateArray_length_p ));
 123     GXV_TRACE(( "entryTable: offset=0x%08x length=0x%08x\n",
 124                 entryTable, *entryTable_length_p ));
 125     GXV_TRACE(( "ligActionTable: offset=0x%08x length=0x%08x\n",
 126                 optdata->ligActionTable,
 127                 optdata->ligActionTable_length ));
 128     GXV_TRACE(( "componentTable: offset=0x%08x length=0x%08x\n",
 129                 optdata->componentTable,
 130                 optdata->componentTable_length ));
 131     GXV_TRACE(( "ligatureTable:  offset=0x%08x length=0x%08x\n",
 132                 optdata->ligatureTable,
 133                 optdata->ligatureTable_length ));
 134
 135     GXV_EXIT;
 136   }
 137
 138
 139 #define GXV_MORX_LIGACTION_ENTRY_SIZE  4
 140
 141
 142   static void
 143   gxv_morx_subtable_type2_ligActionIndex_validate(
 144     FT_Bytes       table,
 145     FT_UShort      ligActionIndex,
 146     GXV_Validator  gxvalid )
 147   {
 148     /* access ligActionTable */
 149     GXV_morx_subtable_type2_StateOptRecData optdata =
 150       (GXV_morx_subtable_type2_StateOptRecData)gxvalid->xstatetable.optdata;
 151
 152     FT_Bytes lat_base  = table + optdata->ligActionTable;
 153     FT_Bytes p         = lat_base +
 154                          ligActionIndex * GXV_MORX_LIGACTION_ENTRY_SIZE;
 155     FT_Bytes lat_limit = lat_base + optdata->ligActionTable;
 156
 157
 158     if ( p < lat_base )
 159     {
 160       GXV_TRACE(( "p < lat_base (%d byte rewind)\n", lat_base - p ));
 161       FT_INVALID_OFFSET;
 162     }
 163     else if ( lat_limit < p )
 164     {
 165       GXV_TRACE(( "lat_limit < p (%d byte overrun)\n", p - lat_limit ));
 166       FT_INVALID_OFFSET;
 167     }
 168
 169     {
 170       /* validate entry in ligActionTable */
 171       FT_ULong   lig_action;
 172 #ifdef GXV_LOAD_UNUSED_VARS
 173       FT_UShort  last;
 174       FT_UShort  store;
 175 #endif
 176       FT_ULong   offset;
 177       FT_Long    gid_limit;
 178
 179
 180       lig_action = FT_NEXT_ULONG( p );
 181 #ifdef GXV_LOAD_UNUSED_VARS
 182       last       = (FT_UShort)( ( lig_action >> 31 ) & 1 );
 183       store      = (FT_UShort)( ( lig_action >> 30 ) & 1 );
 184 #endif
 185
 186       offset = lig_action & 0x3FFFFFFFUL;
 187
 188       /* this offset is 30-bit signed value to add to GID */
 189       /* it is different from the location offset in mort */
 190       if ( ( offset & 0x3FFF0000UL ) == 0x3FFF0000UL )
 191       { /* negative offset */
 192         gid_limit = gxvalid->face->num_glyphs -
 193                     (FT_Long)( offset & 0x0000FFFFUL );
 194         if ( gid_limit > 0 )
 195           return;
 196
 197         GXV_TRACE(( "ligature action table includes"
 198                     " too negative offset moving all GID"
 199                     " below defined range: 0x%04x\n",
 200                     offset & 0xFFFFU ));
 201         GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
 202       }
 203       else if ( ( offset & 0x3FFF0000UL ) == 0x00000000UL )
 204       { /* positive offset */
 205         if ( (FT_Long)offset < gxvalid->face->num_glyphs )
 206           return;
 207
 208         GXV_TRACE(( "ligature action table includes"
 209                     " too large offset moving all GID"
 210                     " over defined range: 0x%04x\n",
 211                     offset & 0xFFFFU ));
 212         GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
 213       }
 214
 215       GXV_TRACE(( "ligature action table includes"
 216                   " invalid offset to add to 16-bit GID:"
 217                   " 0x%08x\n", offset ));
 218       GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
 219     }
 220   }
 221
 222
 223   static void
 224   gxv_morx_subtable_type2_entry_validate(
 225     FT_UShort                       state,
 226     FT_UShort                       flags,
 227     GXV_StateTable_GlyphOffsetCPtr  glyphOffset_p,
 228     FT_Bytes                        table,
 229     FT_Bytes                        limit,
 230     GXV_Validator                   gxvalid )
 231   {
 232 #ifdef GXV_LOAD_UNUSED_VARS
 233     FT_UShort  setComponent;
 234     FT_UShort  dontAdvance;
 235     FT_UShort  performAction;
 236 #endif
 237     FT_UShort  reserved;
 238     FT_UShort  ligActionIndex;
 239
 240     FT_UNUSED( state );
 241     FT_UNUSED( limit );
 242
 243
 244 #ifdef GXV_LOAD_UNUSED_VARS
 245     setComponent   = (FT_UShort)( ( flags >> 15 ) & 1 );
 246     dontAdvance    = (FT_UShort)( ( flags >> 14 ) & 1 );
 247     performAction  = (FT_UShort)( ( flags >> 13 ) & 1 );
 248 #endif
 249
 250     reserved       = (FT_UShort)( flags & 0x1FFF );
 251     ligActionIndex = glyphOffset_p->u;
 252
 253     if ( reserved > 0 )
 254       GXV_TRACE(( "  reserved 14bit is non-zero\n" ));
 255
 256     if ( 0 < ligActionIndex )
 257       gxv_morx_subtable_type2_ligActionIndex_validate(
 258         table, ligActionIndex, gxvalid );
 259   }
 260
 261
 262   static void
 263   gxv_morx_subtable_type2_ligatureTable_validate( FT_Bytes       table,
 264                                                   GXV_Validator  gxvalid )
 265   {
 266     GXV_morx_subtable_type2_StateOptRecData  optdata =
 267       (GXV_morx_subtable_type2_StateOptRecData)gxvalid->xstatetable.optdata;
 268
 269     FT_Bytes p     = table + optdata->ligatureTable;
 270     FT_Bytes limit = table + optdata->ligatureTable
 271                            + optdata->ligatureTable_length;
 272
 273
 274     GXV_NAME_ENTER( "morx chain subtable type2 - substitutionTable" );
 275
 276     if ( 0 != optdata->ligatureTable )
 277     {
 278       /* Apple does not give specification of ligatureTable format */
 279       while ( p < limit )
 280       {
 281         FT_UShort  lig_gid;
 282
 283
 284         GXV_LIMIT_CHECK( 2 );
 285         lig_gid = FT_NEXT_USHORT( p );
 286         if ( lig_gid < gxvalid->face->num_glyphs )
 287           GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
 288       }
 289     }
 290
 291     GXV_EXIT;
 292   }
 293
 294
 295   FT_LOCAL_DEF( void )
 296   gxv_morx_subtable_type2_validate( FT_Bytes       table,
 297                                     FT_Bytes       limit,
 298                                     GXV_Validator  gxvalid )
 299   {
 300     FT_Bytes  p = table;
 301
 302     GXV_morx_subtable_type2_StateOptRec  lig_rec;
 303
 304
 305     GXV_NAME_ENTER( "morx chain subtable type2 (Ligature Substitution)" );
 306
 307     GXV_LIMIT_CHECK( GXV_MORX_SUBTABLE_TYPE2_HEADER_SIZE );
 308
 309     gxvalid->xstatetable.optdata =
 310       &lig_rec;
 311     gxvalid->xstatetable.optdata_load_func =
 312       gxv_morx_subtable_type2_opttable_load;
 313     gxvalid->xstatetable.subtable_setup_func =
 314       gxv_morx_subtable_type2_subtable_setup;
 315     gxvalid->xstatetable.entry_glyphoffset_fmt =
 316       GXV_GLYPHOFFSET_USHORT;
 317     gxvalid->xstatetable.entry_validate_func =
 318       gxv_morx_subtable_type2_entry_validate;
 319
 320     gxv_XStateTable_validate( p, limit, gxvalid );
 321
 322 #if 0
 323     p += gxvalid->subtable_length;
 324 #endif
 325     gxv_morx_subtable_type2_ligatureTable_validate( table, gxvalid );
 326
 327     GXV_EXIT;
 328   }
 329
 330
 331 /* END */