src/gxvalid/gxvmort5.c

   1 /****************************************************************************
   2  *
   3  * gxvmort5.c
   4  *
   5  *   TrueTypeGX/AAT mort table validation
   6  *   body for type5 (Contextual Glyph Insertion) subtable.
   7  *
   8  * Copyright (C) 2005-2023 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 "gxvmort.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  gxvmort
  40
  41
  42   /*
  43    * mort subtable type5 (Contextual Glyph Insertion)
  44    * has the format of StateTable with insertion-glyph-list,
  45    * but without name.  The offset is given by glyphOffset in
  46    * entryTable.  There is no table location declaration
  47    * like xxxTable.
  48    */
  49
  50   typedef struct  GXV_mort_subtable_type5_StateOptRec_
  51   {
  52     FT_UShort   classTable;
  53     FT_UShort   stateArray;
  54     FT_UShort   entryTable;
  55
  56 #define GXV_MORT_SUBTABLE_TYPE5_HEADER_SIZE  GXV_STATETABLE_HEADER_SIZE
  57
  58     FT_UShort*  classTable_length_p;
  59     FT_UShort*  stateArray_length_p;
  60     FT_UShort*  entryTable_length_p;
  61
  62   }  GXV_mort_subtable_type5_StateOptRec,
  63     *GXV_mort_subtable_type5_StateOptRecData;
  64
  65
  66   static void
  67   gxv_mort_subtable_type5_subtable_setup( FT_UShort      table_size,
  68                                           FT_UShort      classTable,
  69                                           FT_UShort      stateArray,
  70                                           FT_UShort      entryTable,
  71                                           FT_UShort*     classTable_length_p,
  72                                           FT_UShort*     stateArray_length_p,
  73                                           FT_UShort*     entryTable_length_p,
  74                                           GXV_Validator  gxvalid )
  75   {
  76     GXV_mort_subtable_type5_StateOptRecData  optdata =
  77       (GXV_mort_subtable_type5_StateOptRecData)gxvalid->statetable.optdata;
  78
  79
  80     gxv_StateTable_subtable_setup( table_size,
  81                                    classTable,
  82                                    stateArray,
  83                                    entryTable,
  84                                    classTable_length_p,
  85                                    stateArray_length_p,
  86                                    entryTable_length_p,
  87                                    gxvalid );
  88
  89     optdata->classTable = classTable;
  90     optdata->stateArray = stateArray;
  91     optdata->entryTable = entryTable;
  92
  93     optdata->classTable_length_p = classTable_length_p;
  94     optdata->stateArray_length_p = stateArray_length_p;
  95     optdata->entryTable_length_p = entryTable_length_p;
  96   }
  97
  98
  99   static void
 100   gxv_mort_subtable_type5_InsertList_validate( FT_UShort      offset,
 101                                                FT_UShort      count,
 102                                                FT_Bytes       table,
 103                                                FT_Bytes       limit,
 104                                                GXV_Validator  gxvalid )
 105   {
 106     /*
 107      * We don't know the range of insertion-glyph-list.
 108      * Set range by whole of state table.
 109      */
 110     FT_Bytes  p = table + offset;
 111
 112     GXV_mort_subtable_type5_StateOptRecData  optdata =
 113       (GXV_mort_subtable_type5_StateOptRecData)gxvalid->statetable.optdata;
 114
 115     if ( optdata->classTable < offset                                   &&
 116          offset < optdata->classTable + *(optdata->classTable_length_p) )
 117       GXV_TRACE(( " offset runs into ClassTable" ));
 118     if ( optdata->stateArray < offset                                   &&
 119          offset < optdata->stateArray + *(optdata->stateArray_length_p) )
 120       GXV_TRACE(( " offset runs into StateArray" ));
 121     if ( optdata->entryTable < offset                                   &&
 122          offset < optdata->entryTable + *(optdata->entryTable_length_p) )
 123       GXV_TRACE(( " offset runs into EntryTable" ));
 124
 125 #ifndef GXV_LOAD_TRACE_VARS
 126     GXV_LIMIT_CHECK( count * 2 );
 127 #else
 128     while ( p < table + offset + ( count * 2 ) )
 129     {
 130       FT_UShort insert_glyphID;
 131
 132
 133       GXV_LIMIT_CHECK( 2 );
 134       insert_glyphID = FT_NEXT_USHORT( p );
 135       GXV_TRACE(( " 0x%04x", insert_glyphID ));
 136     }
 137     GXV_TRACE(( "\n" ));
 138 #endif
 139   }
 140
 141
 142   static void
 143   gxv_mort_subtable_type5_entry_validate(
 144     FT_Byte                         state,
 145     FT_UShort                       flags,
 146     GXV_StateTable_GlyphOffsetCPtr  glyphOffset,
 147     FT_Bytes                        table,
 148     FT_Bytes                        limit,
 149     GXV_Validator                   gxvalid )
 150   {
 151 #ifdef GXV_LOAD_UNUSED_VARS
 152     FT_Bool    setMark;
 153     FT_Bool    dontAdvance;
 154     FT_Bool    currentIsKashidaLike;
 155     FT_Bool    markedIsKashidaLike;
 156     FT_Bool    currentInsertBefore;
 157     FT_Bool    markedInsertBefore;
 158 #endif
 159     FT_Byte    currentInsertCount;
 160     FT_Byte    markedInsertCount;
 161     FT_UShort  currentInsertList;
 162     FT_UShort  markedInsertList;
 163
 164     FT_UNUSED( state );
 165
 166
 167 #ifdef GXV_LOAD_UNUSED_VARS
 168     setMark              = FT_BOOL( ( flags >> 15 ) & 1 );
 169     dontAdvance          = FT_BOOL( ( flags >> 14 ) & 1 );
 170     currentIsKashidaLike = FT_BOOL( ( flags >> 13 ) & 1 );
 171     markedIsKashidaLike  = FT_BOOL( ( flags >> 12 ) & 1 );
 172     currentInsertBefore  = FT_BOOL( ( flags >> 11 ) & 1 );
 173     markedInsertBefore   = FT_BOOL( ( flags >> 10 ) & 1 );
 174 #endif
 175
 176     currentInsertCount   = (FT_Byte)( ( flags >> 5 ) & 0x1F   );
 177     markedInsertCount    = (FT_Byte)(   flags        & 0x001F );
 178
 179     currentInsertList    = (FT_UShort)( glyphOffset->ul >> 16 );
 180     markedInsertList     = (FT_UShort)( glyphOffset->ul       );
 181
 182     if ( 0 != currentInsertList && 0 != currentInsertCount )
 183     {
 184       gxv_mort_subtable_type5_InsertList_validate( currentInsertList,
 185                                                    currentInsertCount,
 186                                                    table,
 187                                                    limit,
 188                                                    gxvalid );
 189     }
 190
 191     if ( 0 != markedInsertList && 0 != markedInsertCount )
 192     {
 193       gxv_mort_subtable_type5_InsertList_validate( markedInsertList,
 194                                                    markedInsertCount,
 195                                                    table,
 196                                                    limit,
 197                                                    gxvalid );
 198     }
 199   }
 200
 201
 202   FT_LOCAL_DEF( void )
 203   gxv_mort_subtable_type5_validate( FT_Bytes       table,
 204                                     FT_Bytes       limit,
 205                                     GXV_Validator  gxvalid )
 206   {
 207     FT_Bytes  p = table;
 208
 209     GXV_mort_subtable_type5_StateOptRec      et_rec;
 210     GXV_mort_subtable_type5_StateOptRecData  et = &et_rec;
 211
 212
 213     GXV_NAME_ENTER( "mort chain subtable type5 (Glyph Insertion)" );
 214
 215     GXV_LIMIT_CHECK( GXV_MORT_SUBTABLE_TYPE5_HEADER_SIZE );
 216
 217     gxvalid->statetable.optdata =
 218       et;
 219     gxvalid->statetable.optdata_load_func =
 220       NULL;
 221     gxvalid->statetable.subtable_setup_func =
 222       gxv_mort_subtable_type5_subtable_setup;
 223     gxvalid->statetable.entry_glyphoffset_fmt =
 224       GXV_GLYPHOFFSET_ULONG;
 225     gxvalid->statetable.entry_validate_func =
 226       gxv_mort_subtable_type5_entry_validate;
 227
 228     gxv_StateTable_validate( p, limit, gxvalid );
 229
 230     GXV_EXIT;
 231   }
 232
 233
 234 /* END */