reactos/dll/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 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 "gxvmorx.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_gxvmorx
  39
  40
  41   typedef struct  GXV_morx_subtable_type2_StateOptRec_
  42   {
  43     FT_ULong  ligActionTable;
  44     FT_ULong  componentTable;
  45     FT_ULong  ligatureTable;
  46     FT_ULong  ligActionTable_length;
  47     FT_ULong  componentTable_length;
  48     FT_ULong  ligatureTable_length;
  49
  50   }  GXV_morx_subtable_type2_StateOptRec,
  51     *GXV_morx_subtable_type2_StateOptRecData;
  52
  53
  54 #define GXV_MORX_SUBTABLE_TYPE2_HEADER_SIZE \
  55           ( GXV_XSTATETABLE_HEADER_SIZE + 4 + 4 + 4 )
  56
  57
  58   static void
  59   gxv_morx_subtable_type2_opttable_load( FT_Bytes       table,
  60                                          FT_Bytes       limit,
  61                                          GXV_Validator  valid )
  62   {
  63     FT_Bytes  p = table;
  64
  65     GXV_morx_subtable_type2_StateOptRecData  optdata =
  66       (GXV_morx_subtable_type2_StateOptRecData)valid->xstatetable.optdata;
  67
  68
  69     GXV_LIMIT_CHECK( 4 + 4 + 4 );
  70     optdata->ligActionTable = FT_NEXT_ULONG( p );
  71     optdata->componentTable = FT_NEXT_ULONG( p );
  72     optdata->ligatureTable  = FT_NEXT_ULONG( p );
  73
  74     GXV_TRACE(( "offset to ligActionTable=0x%08x\n",
  75                 optdata->ligActionTable ));
  76     GXV_TRACE(( "offset to componentTable=0x%08x\n",
  77                 optdata->componentTable ));
  78     GXV_TRACE(( "offset to ligatureTable=0x%08x\n",
  79                 optdata->ligatureTable ));
  80   }
  81
  82
  83   static void
  84   gxv_morx_subtable_type2_subtable_setup( FT_ULong       table_size,
  85                                           FT_ULong       classTable,
  86                                           FT_ULong       stateArray,
  87                                           FT_ULong       entryTable,
  88                                           FT_ULong*      classTable_length_p,
  89                                           FT_ULong*      stateArray_length_p,
  90                                           FT_ULong*      entryTable_length_p,
  91                                           GXV_Validator  valid )
  92   {
  93     FT_ULong   o[6];
  94     FT_ULong*  l[6];
  95     FT_ULong   buff[7];
  96
  97     GXV_morx_subtable_type2_StateOptRecData  optdata =
  98       (GXV_morx_subtable_type2_StateOptRecData)valid->xstatetable.optdata;
  99
 100
 101     GXV_NAME_ENTER( "subtable boundaries setup" );
 102
 103     o[0] = classTable;
 104     o[1] = stateArray;
 105     o[2] = entryTable;
 106     o[3] = optdata->ligActionTable;
 107     o[4] = optdata->componentTable;
 108     o[5] = optdata->ligatureTable;
 109     l[0] = classTable_length_p;
 110     l[1] = stateArray_length_p;
 111     l[2] = entryTable_length_p;
 112     l[3] = &(optdata->ligActionTable_length);
 113     l[4] = &(optdata->componentTable_length);
 114     l[5] = &(optdata->ligatureTable_length);
 115
 116     gxv_set_length_by_ulong_offset( o, l, buff, 6, table_size, valid );
 117
 118     GXV_TRACE(( "classTable: offset=0x%08x length=0x%08x\n",
 119                 classTable, *classTable_length_p ));
 120     GXV_TRACE(( "stateArray: offset=0x%08x length=0x%08x\n",
 121                 stateArray, *stateArray_length_p ));
 122     GXV_TRACE(( "entryTable: offset=0x%08x length=0x%08x\n",
 123                 entryTable, *entryTable_length_p ));
 124     GXV_TRACE(( "ligActionTable: offset=0x%08x length=0x%08x\n",
 125                 optdata->ligActionTable,
 126                 optdata->ligActionTable_length ));
 127     GXV_TRACE(( "componentTable: offset=0x%08x length=0x%08x\n",
 128                 optdata->componentTable,
 129                 optdata->componentTable_length ));
 130     GXV_TRACE(( "ligatureTable:  offset=0x%08x length=0x%08x\n",
 131                 optdata->ligatureTable,
 132                 optdata->ligatureTable_length ));
 133
 134     GXV_EXIT;
 135   }
 136
 137
 138 #define GXV_MORX_LIGACTION_ENTRY_SIZE  4
 139
 140
 141   static void
 142   gxv_morx_subtable_type2_ligActionIndex_validate(
 143     FT_Bytes       table,
 144     FT_UShort      ligActionIndex,
 145     GXV_Validator  valid )
 146   {
 147     /* access ligActionTable */
 148     GXV_morx_subtable_type2_StateOptRecData optdata =
 149       (GXV_morx_subtable_type2_StateOptRecData)valid->xstatetable.optdata;
 150
 151     FT_Bytes lat_base  = table + optdata->ligActionTable;
 152     FT_Bytes p         = lat_base +
 153                          ligActionIndex * GXV_MORX_LIGACTION_ENTRY_SIZE;
 154     FT_Bytes lat_limit = lat_base + optdata->ligActionTable;
 155
 156
 157     if ( p < lat_base )
 158     {
 159       GXV_TRACE(( "p < lat_base (%d byte rewind)\n", lat_base - p ));
 160       FT_INVALID_OFFSET;
 161     }
 162     else if ( lat_limit < p )
 163     {
 164       GXV_TRACE(( "lat_limit < p (%d byte overrun)\n", p - lat_limit ));
 165       FT_INVALID_OFFSET;
 166     }
 167
 168     {
 169       /* validate entry in ligActionTable */
 170       FT_ULong   lig_action;
 171       FT_UShort  last;
 172       FT_UShort  store;
 173       FT_ULong   offset;
 174
 175
 176       lig_action = FT_NEXT_ULONG( p );
 177       last       = (FT_UShort)( ( lig_action >> 31 ) & 1 );
 178       store      = (FT_UShort)( ( lig_action >> 30 ) & 1 );
 179
 180       offset = lig_action & 0x3FFFFFFFUL;
 181     }
 182   }
 183
 184
 185   static void
 186   gxv_morx_subtable_type2_entry_validate(
 187     FT_UShort                       state,
 188     FT_UShort                       flags,
 189     GXV_StateTable_GlyphOffsetDesc  glyphOffset,
 190     FT_Bytes                        table,
 191     FT_Bytes                        limit,
 192     GXV_Validator                   valid )
 193   {
 194     FT_UShort  setComponent;
 195     FT_UShort  dontAdvance;
 196     FT_UShort  performAction;
 197     FT_UShort  reserved;
 198     FT_UShort  ligActionIndex;
 199
 200     FT_UNUSED( state );
 201     FT_UNUSED( limit );
 202
 203
 204     setComponent   = (FT_UShort)( ( flags >> 15 ) & 1 );
 205     dontAdvance    = (FT_UShort)( ( flags >> 14 ) & 1 );
 206     performAction  = (FT_UShort)( ( flags >> 13 ) & 1 );
 207
 208     reserved       = (FT_UShort)( flags & 0x1FFF );
 209     ligActionIndex = glyphOffset.u;
 210
 211     if ( reserved > 0 )
 212       GXV_TRACE(( "  reserved 14bit is non-zero\n" ));
 213
 214     if ( 0 < ligActionIndex )
 215       gxv_morx_subtable_type2_ligActionIndex_validate(
 216         table, ligActionIndex, valid );
 217   }
 218
 219
 220   static void
 221   gxv_morx_subtable_type2_ligatureTable_validate( FT_Bytes       table,
 222                                                   GXV_Validator  valid )
 223   {
 224     GXV_morx_subtable_type2_StateOptRecData  optdata =
 225       (GXV_morx_subtable_type2_StateOptRecData)valid->xstatetable.optdata;
 226
 227     FT_Bytes p     = table + optdata->ligatureTable;
 228     FT_Bytes limit = table + optdata->ligatureTable
 229                            + optdata->ligatureTable_length;
 230
 231
 232     GXV_NAME_ENTER( "morx chain subtable type2 - substitutionTable" );
 233
 234     if ( 0 != optdata->ligatureTable )
 235     {
 236       /* Apple does not give specification of ligatureTable format */
 237       while ( p < limit )
 238       {
 239         FT_UShort  lig_gid;
 240
 241
 242         GXV_LIMIT_CHECK( 2 );
 243         lig_gid = FT_NEXT_USHORT( p );
 244       }
 245     }
 246
 247     GXV_EXIT;
 248   }
 249
 250
 251   FT_LOCAL_DEF( void )
 252   gxv_morx_subtable_type2_validate( FT_Bytes       table,
 253                                     FT_Bytes       limit,
 254                                     GXV_Validator  valid )
 255   {
 256     FT_Bytes  p = table;
 257
 258     GXV_morx_subtable_type2_StateOptRec  lig_rec;
 259
 260
 261     GXV_NAME_ENTER( "morx chain subtable type2 (Ligature Substitution)" );
 262
 263     GXV_LIMIT_CHECK( GXV_MORX_SUBTABLE_TYPE2_HEADER_SIZE );
 264
 265     valid->xstatetable.optdata =
 266       &lig_rec;
 267     valid->xstatetable.optdata_load_func =
 268       gxv_morx_subtable_type2_opttable_load;
 269     valid->xstatetable.subtable_setup_func =
 270       gxv_morx_subtable_type2_subtable_setup;
 271     valid->xstatetable.entry_glyphoffset_fmt =
 272       GXV_GLYPHOFFSET_USHORT;
 273     valid->xstatetable.entry_validate_func =
 274       gxv_morx_subtable_type2_entry_validate;
 275
 276     gxv_XStateTable_validate( p, limit, valid );
 277
 278     p += valid->subtable_length;
 279     gxv_morx_subtable_type2_ligatureTable_validate( table, valid );
 280
 281     GXV_EXIT;
 282   }
 283
 284
 285 /* END */