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gxvcommn.c (54281B)


      1 /****************************************************************************
      2 *
      3 * gxvcommn.c
      4 *
      5 *   TrueTypeGX/AAT common tables validation (body).
      6 *
      7 * Copyright (C) 2004-2025 by
      8 * 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 "gxvcommn.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  gxvcommon
     39 
     40 
     41  /*************************************************************************/
     42  /*************************************************************************/
     43  /*****                                                               *****/
     44  /*****                       16bit offset sorter                     *****/
     45  /*****                                                               *****/
     46  /*************************************************************************/
     47  /*************************************************************************/
     48 
     49  FT_COMPARE_DEF( int )
     50  gxv_compare_ushort_offset( const void*  a,
     51                             const void*  b )
     52  {
     53    return  *(FT_UShort*)a - *(FT_UShort*)b;
     54  }
     55 
     56 
     57  FT_LOCAL_DEF( void )
     58  gxv_set_length_by_ushort_offset( FT_UShort*     offset,
     59                                   FT_UShort**    length,
     60                                   FT_UShort*     buff,
     61                                   FT_UInt        nmemb,
     62                                   FT_UShort      limit,
     63                                   GXV_Validator  gxvalid )
     64  {
     65    FT_UInt  i;
     66 
     67 
     68    for ( i = 0; i < nmemb; i++ )
     69      *(length[i]) = 0;
     70 
     71    for ( i = 0; i < nmemb; i++ )
     72      buff[i] = offset[i];
     73    buff[nmemb] = limit;
     74 
     75    ft_qsort( buff, ( nmemb + 1 ), sizeof ( FT_UShort ),
     76              gxv_compare_ushort_offset );
     77 
     78    if ( buff[nmemb] > limit )
     79      FT_INVALID_OFFSET;
     80 
     81    for ( i = 0; i < nmemb; i++ )
     82    {
     83      FT_UInt  j;
     84 
     85 
     86      for ( j = 0; j < nmemb; j++ )
     87        if ( buff[j] == offset[i] )
     88          break;
     89 
     90      if ( j == nmemb )
     91        FT_INVALID_OFFSET;
     92 
     93      *(length[i]) = (FT_UShort)( buff[j + 1] - buff[j] );
     94 
     95      if ( 0 != offset[i] && 0 == *(length[i]) )
     96        FT_INVALID_OFFSET;
     97    }
     98  }
     99 
    100 
    101  /*************************************************************************/
    102  /*************************************************************************/
    103  /*****                                                               *****/
    104  /*****                       32bit offset sorter                     *****/
    105  /*****                                                               *****/
    106  /*************************************************************************/
    107  /*************************************************************************/
    108 
    109  FT_COMPARE_DEF( int )
    110  gxv_compare_ulong_offset( const void*  a,
    111                            const void*  b )
    112  {
    113    FT_ULong  a_ = *(FT_ULong*)a;
    114    FT_ULong  b_ = *(FT_ULong*)b;
    115 
    116 
    117    if ( a_ < b_ )
    118      return -1;
    119    else if ( a_ > b_ )
    120      return 1;
    121    else
    122      return 0;
    123  }
    124 
    125 
    126  FT_LOCAL_DEF( void )
    127  gxv_set_length_by_ulong_offset( FT_ULong*      offset,
    128                                  FT_ULong**     length,
    129                                  FT_ULong*      buff,
    130                                  FT_UInt        nmemb,
    131                                  FT_ULong       limit,
    132                                  GXV_Validator  gxvalid)
    133  {
    134    FT_UInt  i;
    135 
    136 
    137    for ( i = 0; i < nmemb; i++ )
    138      *(length[i]) = 0;
    139 
    140    for ( i = 0; i < nmemb; i++ )
    141      buff[i] = offset[i];
    142    buff[nmemb] = limit;
    143 
    144    ft_qsort( buff, ( nmemb + 1 ), sizeof ( FT_ULong ),
    145              gxv_compare_ulong_offset );
    146 
    147    if ( buff[nmemb] > limit )
    148      FT_INVALID_OFFSET;
    149 
    150    for ( i = 0; i < nmemb; i++ )
    151    {
    152      FT_UInt  j;
    153 
    154 
    155      for ( j = 0; j < nmemb; j++ )
    156        if ( buff[j] == offset[i] )
    157          break;
    158 
    159      if ( j == nmemb )
    160        FT_INVALID_OFFSET;
    161 
    162      *(length[i]) = buff[j + 1] - buff[j];
    163 
    164      if ( 0 != offset[i] && 0 == *(length[i]) )
    165        FT_INVALID_OFFSET;
    166    }
    167  }
    168 
    169 
    170  /*************************************************************************/
    171  /*************************************************************************/
    172  /*****                                                               *****/
    173  /*****               scan value array and get min & max              *****/
    174  /*****                                                               *****/
    175  /*************************************************************************/
    176  /*************************************************************************/
    177 
    178 
    179  FT_LOCAL_DEF( void )
    180  gxv_array_getlimits_byte( FT_Bytes       table,
    181                            FT_Bytes       limit,
    182                            FT_Byte*       min,
    183                            FT_Byte*       max,
    184                            GXV_Validator  gxvalid )
    185  {
    186    FT_Bytes  p = table;
    187 
    188 
    189    *min = 0xFF;
    190    *max = 0x00;
    191 
    192    while ( p < limit )
    193    {
    194      FT_Byte  val;
    195 
    196 
    197      GXV_LIMIT_CHECK( 1 );
    198      val = FT_NEXT_BYTE( p );
    199 
    200      *min = (FT_Byte)FT_MIN( *min, val );
    201      *max = (FT_Byte)FT_MAX( *max, val );
    202    }
    203 
    204    gxvalid->subtable_length = (FT_ULong)( p - table );
    205  }
    206 
    207 
    208  FT_LOCAL_DEF( void )
    209  gxv_array_getlimits_ushort( FT_Bytes       table,
    210                              FT_Bytes       limit,
    211                              FT_UShort*     min,
    212                              FT_UShort*     max,
    213                              GXV_Validator  gxvalid )
    214  {
    215    FT_Bytes  p = table;
    216 
    217 
    218    *min = 0xFFFFU;
    219    *max = 0x0000;
    220 
    221    while ( p < limit )
    222    {
    223      FT_UShort  val;
    224 
    225 
    226      GXV_LIMIT_CHECK( 2 );
    227      val = FT_NEXT_USHORT( p );
    228 
    229      *min = (FT_Byte)FT_MIN( *min, val );
    230      *max = (FT_Byte)FT_MAX( *max, val );
    231    }
    232 
    233    gxvalid->subtable_length = (FT_ULong)( p - table );
    234  }
    235 
    236 
    237  /*************************************************************************/
    238  /*************************************************************************/
    239  /*****                                                               *****/
    240  /*****                       BINSEARCHHEADER                         *****/
    241  /*****                                                               *****/
    242  /*************************************************************************/
    243  /*************************************************************************/
    244 
    245  typedef struct  GXV_BinSrchHeader_
    246  {
    247    FT_UShort  unitSize;
    248    FT_UShort  nUnits;
    249    FT_UShort  searchRange;
    250    FT_UShort  entrySelector;
    251    FT_UShort  rangeShift;
    252 
    253  } GXV_BinSrchHeader;
    254 
    255 
    256  static void
    257  gxv_BinSrchHeader_check_consistency( GXV_BinSrchHeader*  binSrchHeader,
    258                                       GXV_Validator       gxvalid )
    259  {
    260    FT_UShort  searchRange;
    261    FT_UShort  entrySelector;
    262    FT_UShort  rangeShift;
    263 
    264 
    265    if ( binSrchHeader->unitSize == 0 )
    266      FT_INVALID_DATA;
    267 
    268    if ( binSrchHeader->nUnits == 0 )
    269    {
    270      if ( binSrchHeader->searchRange   == 0 &&
    271           binSrchHeader->entrySelector == 0 &&
    272           binSrchHeader->rangeShift    == 0 )
    273        return;
    274      else
    275        FT_INVALID_DATA;
    276    }
    277 
    278    for ( searchRange = 1, entrySelector = 1;
    279          ( searchRange * 2 ) <= binSrchHeader->nUnits &&
    280            searchRange < 0x8000U;
    281          searchRange *= 2, entrySelector++ )
    282      ;
    283 
    284    entrySelector--;
    285    searchRange = (FT_UShort)( searchRange * binSrchHeader->unitSize );
    286    rangeShift  = (FT_UShort)( binSrchHeader->nUnits * binSrchHeader->unitSize
    287                               - searchRange );
    288 
    289    if ( searchRange   != binSrchHeader->searchRange   ||
    290         entrySelector != binSrchHeader->entrySelector ||
    291         rangeShift    != binSrchHeader->rangeShift    )
    292    {
    293      GXV_TRACE(( "Inconsistency found in BinSrchHeader\n" ));
    294      GXV_TRACE(( "originally: unitSize=%d, nUnits=%d, "
    295                  "searchRange=%d, entrySelector=%d, "
    296                  "rangeShift=%d\n",
    297                  binSrchHeader->unitSize, binSrchHeader->nUnits,
    298                  binSrchHeader->searchRange, binSrchHeader->entrySelector,
    299                  binSrchHeader->rangeShift ));
    300      GXV_TRACE(( "calculated: unitSize=%d, nUnits=%d, "
    301                  "searchRange=%d, entrySelector=%d, "
    302                  "rangeShift=%d\n",
    303                  binSrchHeader->unitSize, binSrchHeader->nUnits,
    304                  searchRange, entrySelector, rangeShift ));
    305 
    306      GXV_SET_ERR_IF_PARANOID( FT_INVALID_DATA );
    307    }
    308  }
    309 
    310 
    311  /*
    312   * parser & validator of BinSrchHeader
    313   * which is used in LookupTable format 2, 4, 6.
    314   *
    315   * Essential parameters (unitSize, nUnits) are returned by
    316   * given pointer, others (searchRange, entrySelector, rangeShift)
    317   * can be calculated by essential parameters, so they are just
    318   * validated and discarded.
    319   *
    320   * However, wrong values in searchRange, entrySelector, rangeShift
    321   * won't cause fatal errors, because these parameters might be
    322   * only used in old m68k font driver in MacOS.
    323   *   -- suzuki toshiya <mpsuzuki@hiroshima-u.ac.jp>
    324   */
    325 
    326  FT_LOCAL_DEF( void )
    327  gxv_BinSrchHeader_validate( FT_Bytes       table,
    328                              FT_Bytes       limit,
    329                              FT_UShort*     unitSize_p,
    330                              FT_UShort*     nUnits_p,
    331                              GXV_Validator  gxvalid )
    332  {
    333    FT_Bytes           p = table;
    334    GXV_BinSrchHeader  binSrchHeader;
    335 
    336 
    337    GXV_NAME_ENTER( "BinSrchHeader validate" );
    338 
    339    if ( *unitSize_p == 0 )
    340    {
    341      GXV_LIMIT_CHECK( 2 );
    342      binSrchHeader.unitSize =  FT_NEXT_USHORT( p );
    343    }
    344    else
    345      binSrchHeader.unitSize = *unitSize_p;
    346 
    347    if ( *nUnits_p == 0 )
    348    {
    349      GXV_LIMIT_CHECK( 2 );
    350      binSrchHeader.nUnits = FT_NEXT_USHORT( p );
    351    }
    352    else
    353      binSrchHeader.nUnits = *nUnits_p;
    354 
    355    GXV_LIMIT_CHECK( 2 + 2 + 2 );
    356    binSrchHeader.searchRange   = FT_NEXT_USHORT( p );
    357    binSrchHeader.entrySelector = FT_NEXT_USHORT( p );
    358    binSrchHeader.rangeShift    = FT_NEXT_USHORT( p );
    359    GXV_TRACE(( "nUnits %d\n", binSrchHeader.nUnits ));
    360 
    361    gxv_BinSrchHeader_check_consistency( &binSrchHeader, gxvalid );
    362 
    363    if ( *unitSize_p == 0 )
    364      *unitSize_p = binSrchHeader.unitSize;
    365 
    366    if ( *nUnits_p == 0 )
    367      *nUnits_p = binSrchHeader.nUnits;
    368 
    369    gxvalid->subtable_length = (FT_ULong)( p - table );
    370    GXV_EXIT;
    371  }
    372 
    373 
    374  /*************************************************************************/
    375  /*************************************************************************/
    376  /*****                                                               *****/
    377  /*****                         LOOKUP TABLE                          *****/
    378  /*****                                                               *****/
    379  /*************************************************************************/
    380  /*************************************************************************/
    381 
    382 #define GXV_LOOKUP_VALUE_LOAD( P, SIGNSPEC )                   \
    383          ( P += 2, gxv_lookup_value_load( P - 2, SIGNSPEC ) )
    384 
    385  static GXV_LookupValueDesc
    386  gxv_lookup_value_load( FT_Bytes                  p,
    387                         GXV_LookupValue_SignSpec  signspec )
    388  {
    389    GXV_LookupValueDesc  v;
    390 
    391 
    392    if ( signspec == GXV_LOOKUPVALUE_UNSIGNED )
    393      v.u = FT_NEXT_USHORT( p );
    394    else
    395      v.s = FT_NEXT_SHORT( p );
    396 
    397    return v;
    398  }
    399 
    400 
    401 #define GXV_UNITSIZE_VALIDATE( FORMAT, UNITSIZE, NUNITS, CORRECTSIZE ) \
    402          FT_BEGIN_STMNT                                               \
    403            if ( UNITSIZE != CORRECTSIZE )                             \
    404            {                                                          \
    405              FT_ERROR(( "unitSize=%d differs from"                    \
    406                         " expected unitSize=%d"                       \
    407                         " in LookupTable %s\n",                       \
    408                          UNITSIZE, CORRECTSIZE, FORMAT ));            \
    409              if ( UNITSIZE != 0 && NUNITS != 0 )                      \
    410              {                                                        \
    411                FT_ERROR(( " cannot validate anymore\n" ));            \
    412                FT_INVALID_FORMAT;                                     \
    413              }                                                        \
    414              else                                                     \
    415                FT_ERROR(( " forcibly continues\n" ));                 \
    416            }                                                          \
    417          FT_END_STMNT
    418 
    419 
    420  /* ================= Simple Array Format 0 Lookup Table ================ */
    421  static void
    422  gxv_LookupTable_fmt0_validate( FT_Bytes       table,
    423                                 FT_Bytes       limit,
    424                                 GXV_Validator  gxvalid )
    425  {
    426    FT_Bytes   p = table;
    427    FT_UShort  i;
    428 
    429    GXV_LookupValueDesc  value;
    430 
    431 
    432    GXV_NAME_ENTER( "LookupTable format 0" );
    433 
    434    GXV_LIMIT_CHECK( 2 * gxvalid->face->num_glyphs );
    435 
    436    for ( i = 0; i < gxvalid->face->num_glyphs; i++ )
    437    {
    438      GXV_LIMIT_CHECK( 2 );
    439      if ( p + 2 >= limit )     /* some fonts have too-short fmt0 array */
    440      {
    441        GXV_TRACE(( "too short, glyphs %d - %ld are missing\n",
    442                    i, gxvalid->face->num_glyphs ));
    443        GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
    444        break;
    445      }
    446 
    447      value = GXV_LOOKUP_VALUE_LOAD( p, gxvalid->lookupval_sign );
    448      gxvalid->lookupval_func( i, &value, gxvalid );
    449    }
    450 
    451    gxvalid->subtable_length = (FT_ULong)( p - table );
    452    GXV_EXIT;
    453  }
    454 
    455 
    456  /* ================= Segment Single Format 2 Lookup Table ============== */
    457  /*
    458   * Apple spec says:
    459   *
    460   *   To guarantee that a binary search terminates, you must include one or
    461   *   more special `end of search table' values at the end of the data to
    462   *   be searched.  The number of termination values that need to be
    463   *   included is table-specific.  The value that indicates binary search
    464   *   termination is 0xFFFF.
    465   *
    466   * The problem is that nUnits does not include this end-marker.  It's
    467   * quite difficult to discriminate whether the following 0xFFFF comes from
    468   * the end-marker or some next data.
    469   *
    470   *   -- suzuki toshiya <mpsuzuki@hiroshima-u.ac.jp>
    471   */
    472  static void
    473  gxv_LookupTable_fmt2_skip_endmarkers( FT_Bytes       table,
    474                                        FT_UShort      unitSize,
    475                                        GXV_Validator  gxvalid )
    476  {
    477    FT_Bytes  p = table;
    478 
    479 
    480    while ( ( p + 4 ) < gxvalid->root->limit )
    481    {
    482      if ( p[0] != 0xFF || p[1] != 0xFF || /* lastGlyph */
    483           p[2] != 0xFF || p[3] != 0xFF )  /* firstGlyph */
    484        break;
    485      p += unitSize;
    486    }
    487 
    488    gxvalid->subtable_length = (FT_ULong)( p - table );
    489  }
    490 
    491 
    492  static void
    493  gxv_LookupTable_fmt2_validate( FT_Bytes       table,
    494                                 FT_Bytes       limit,
    495                                 GXV_Validator  gxvalid )
    496  {
    497    FT_Bytes             p = table;
    498    FT_UShort            gid;
    499 
    500    FT_UShort            unitSize;
    501    FT_UShort            nUnits;
    502    FT_UShort            unit;
    503    FT_UShort            lastGlyph;
    504    FT_UShort            firstGlyph;
    505    GXV_LookupValueDesc  value;
    506 
    507 
    508    GXV_NAME_ENTER( "LookupTable format 2" );
    509 
    510    unitSize = nUnits = 0;
    511    gxv_BinSrchHeader_validate( p, limit, &unitSize, &nUnits, gxvalid );
    512    p += gxvalid->subtable_length;
    513 
    514    GXV_UNITSIZE_VALIDATE( "format2", unitSize, nUnits, 6 );
    515 
    516    for ( unit = 0, gid = 0; unit < nUnits; unit++ )
    517    {
    518      GXV_LIMIT_CHECK( 2 + 2 + 2 );
    519      lastGlyph  = FT_NEXT_USHORT( p );
    520      firstGlyph = FT_NEXT_USHORT( p );
    521      value      = GXV_LOOKUP_VALUE_LOAD( p, gxvalid->lookupval_sign );
    522 
    523      gxv_glyphid_validate( firstGlyph, gxvalid );
    524      gxv_glyphid_validate( lastGlyph, gxvalid );
    525 
    526      if ( lastGlyph < gid )
    527      {
    528        GXV_TRACE(( "reverse ordered segment specification:"
    529                    " lastGlyph[%d]=%d < lastGlyph[%d]=%d\n",
    530                    unit, lastGlyph, unit - 1 , gid ));
    531        GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
    532      }
    533 
    534      if ( lastGlyph < firstGlyph )
    535      {
    536        GXV_TRACE(( "reverse ordered range specification at unit %d:"
    537                    " lastGlyph %d < firstGlyph %d ",
    538                    unit, lastGlyph, firstGlyph ));
    539        GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
    540 
    541        if ( gxvalid->root->level == FT_VALIDATE_TIGHT )
    542          continue;     /* ftxvalidator silently skips such an entry */
    543 
    544        FT_TRACE4(( "continuing with exchanged values\n" ));
    545        gid        = firstGlyph;
    546        firstGlyph = lastGlyph;
    547        lastGlyph  = gid;
    548      }
    549 
    550      for ( gid = firstGlyph; gid <= lastGlyph; gid++ )
    551        gxvalid->lookupval_func( gid, &value, gxvalid );
    552    }
    553 
    554    gxv_LookupTable_fmt2_skip_endmarkers( p, unitSize, gxvalid );
    555    p += gxvalid->subtable_length;
    556 
    557    gxvalid->subtable_length = (FT_ULong)( p - table );
    558    GXV_EXIT;
    559  }
    560 
    561 
    562  /* ================= Segment Array Format 4 Lookup Table =============== */
    563  static void
    564  gxv_LookupTable_fmt4_validate( FT_Bytes       table,
    565                                 FT_Bytes       limit,
    566                                 GXV_Validator  gxvalid )
    567  {
    568    FT_Bytes             p = table;
    569    FT_UShort            unit;
    570    FT_UShort            gid;
    571 
    572    FT_UShort            unitSize;
    573    FT_UShort            nUnits;
    574    FT_UShort            lastGlyph;
    575    FT_UShort            firstGlyph;
    576    GXV_LookupValueDesc  base_value;
    577    GXV_LookupValueDesc  value;
    578 
    579 
    580    GXV_NAME_ENTER( "LookupTable format 4" );
    581 
    582    unitSize = nUnits = 0;
    583    gxv_BinSrchHeader_validate( p, limit, &unitSize, &nUnits, gxvalid );
    584    p += gxvalid->subtable_length;
    585 
    586    GXV_UNITSIZE_VALIDATE( "format4", unitSize, nUnits, 6 );
    587 
    588    for ( unit = 0, gid = 0; unit < nUnits; unit++ )
    589    {
    590      GXV_LIMIT_CHECK( 2 + 2 );
    591      lastGlyph  = FT_NEXT_USHORT( p );
    592      firstGlyph = FT_NEXT_USHORT( p );
    593 
    594      gxv_glyphid_validate( firstGlyph, gxvalid );
    595      gxv_glyphid_validate( lastGlyph, gxvalid );
    596 
    597      if ( lastGlyph < gid )
    598      {
    599        GXV_TRACE(( "reverse ordered segment specification:"
    600                    " lastGlyph[%d]=%d < lastGlyph[%d]=%d\n",
    601                    unit, lastGlyph, unit - 1 , gid ));
    602        GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
    603      }
    604 
    605      if ( lastGlyph < firstGlyph )
    606      {
    607        GXV_TRACE(( "reverse ordered range specification at unit %d:"
    608                    " lastGlyph %d < firstGlyph %d ",
    609                    unit, lastGlyph, firstGlyph ));
    610        GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
    611 
    612        if ( gxvalid->root->level == FT_VALIDATE_TIGHT )
    613          continue; /* ftxvalidator silently skips such an entry */
    614 
    615        FT_TRACE4(( "continuing with exchanged values\n" ));
    616        gid        = firstGlyph;
    617        firstGlyph = lastGlyph;
    618        lastGlyph  = gid;
    619      }
    620 
    621      GXV_LIMIT_CHECK( 2 );
    622      base_value = GXV_LOOKUP_VALUE_LOAD( p, GXV_LOOKUPVALUE_UNSIGNED );
    623 
    624      for ( gid = firstGlyph; gid <= lastGlyph; gid++ )
    625      {
    626        value = gxvalid->lookupfmt4_trans( (FT_UShort)( gid - firstGlyph ),
    627                                         &base_value,
    628                                         limit,
    629                                         gxvalid );
    630 
    631        gxvalid->lookupval_func( gid, &value, gxvalid );
    632      }
    633    }
    634 
    635    gxv_LookupTable_fmt2_skip_endmarkers( p, unitSize, gxvalid );
    636    p += gxvalid->subtable_length;
    637 
    638    gxvalid->subtable_length = (FT_ULong)( p - table );
    639    GXV_EXIT;
    640  }
    641 
    642 
    643  /* ================= Segment Table Format 6 Lookup Table =============== */
    644  static void
    645  gxv_LookupTable_fmt6_skip_endmarkers( FT_Bytes       table,
    646                                        FT_UShort      unitSize,
    647                                        GXV_Validator  gxvalid )
    648  {
    649    FT_Bytes  p = table;
    650 
    651 
    652    while ( p < gxvalid->root->limit )
    653    {
    654      if ( p[0] != 0xFF || p[1] != 0xFF )
    655        break;
    656      p += unitSize;
    657    }
    658 
    659    gxvalid->subtable_length = (FT_ULong)( p - table );
    660  }
    661 
    662 
    663  static void
    664  gxv_LookupTable_fmt6_validate( FT_Bytes       table,
    665                                 FT_Bytes       limit,
    666                                 GXV_Validator  gxvalid )
    667  {
    668    FT_Bytes             p = table;
    669    FT_UShort            unit;
    670    FT_UShort            prev_glyph;
    671 
    672    FT_UShort            unitSize;
    673    FT_UShort            nUnits;
    674    FT_UShort            glyph;
    675    GXV_LookupValueDesc  value;
    676 
    677 
    678    GXV_NAME_ENTER( "LookupTable format 6" );
    679 
    680    unitSize = nUnits = 0;
    681    gxv_BinSrchHeader_validate( p, limit, &unitSize, &nUnits, gxvalid );
    682    p += gxvalid->subtable_length;
    683 
    684    GXV_UNITSIZE_VALIDATE( "format6", unitSize, nUnits, 4 );
    685 
    686    for ( unit = 0, prev_glyph = 0; unit < nUnits; unit++ )
    687    {
    688      GXV_LIMIT_CHECK( 2 + 2 );
    689      glyph = FT_NEXT_USHORT( p );
    690      value = GXV_LOOKUP_VALUE_LOAD( p, gxvalid->lookupval_sign );
    691 
    692      if ( gxv_glyphid_validate( glyph, gxvalid ) )
    693        GXV_TRACE(( " endmarker found within defined range"
    694                    " (entry %d < nUnits=%d)\n",
    695                    unit, nUnits ));
    696 
    697      if ( prev_glyph > glyph )
    698      {
    699        GXV_TRACE(( "current gid 0x%04x < previous gid 0x%04x\n",
    700                    glyph, prev_glyph ));
    701        GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
    702      }
    703      prev_glyph = glyph;
    704 
    705      gxvalid->lookupval_func( glyph, &value, gxvalid );
    706    }
    707 
    708    gxv_LookupTable_fmt6_skip_endmarkers( p, unitSize, gxvalid );
    709    p += gxvalid->subtable_length;
    710 
    711    gxvalid->subtable_length = (FT_ULong)( p - table );
    712    GXV_EXIT;
    713  }
    714 
    715 
    716  /* ================= Trimmed Array Format 8 Lookup Table =============== */
    717  static void
    718  gxv_LookupTable_fmt8_validate( FT_Bytes       table,
    719                                 FT_Bytes       limit,
    720                                 GXV_Validator  gxvalid )
    721  {
    722    FT_Bytes              p = table;
    723    FT_UShort             i;
    724 
    725    GXV_LookupValueDesc   value;
    726    FT_UShort             firstGlyph;
    727    FT_UShort             glyphCount;
    728 
    729 
    730    GXV_NAME_ENTER( "LookupTable format 8" );
    731 
    732    /* firstGlyph + glyphCount */
    733    GXV_LIMIT_CHECK( 2 + 2 );
    734    firstGlyph = FT_NEXT_USHORT( p );
    735    glyphCount = FT_NEXT_USHORT( p );
    736 
    737    gxv_glyphid_validate( firstGlyph, gxvalid );
    738    gxv_glyphid_validate( (FT_UShort)( firstGlyph + glyphCount ), gxvalid );
    739 
    740    /* valueArray */
    741    for ( i = 0; i < glyphCount; i++ )
    742    {
    743      GXV_LIMIT_CHECK( 2 );
    744      value = GXV_LOOKUP_VALUE_LOAD( p, gxvalid->lookupval_sign );
    745      gxvalid->lookupval_func( (FT_UShort)( firstGlyph + i ), &value, gxvalid );
    746    }
    747 
    748    gxvalid->subtable_length = (FT_ULong)( p - table );
    749    GXV_EXIT;
    750  }
    751 
    752 
    753  FT_LOCAL_DEF( void )
    754  gxv_LookupTable_validate( FT_Bytes       table,
    755                            FT_Bytes       limit,
    756                            GXV_Validator  gxvalid )
    757  {
    758    FT_Bytes   p = table;
    759    FT_UShort  format;
    760 
    761    GXV_Validate_Func  fmt_funcs_table[] =
    762    {
    763      gxv_LookupTable_fmt0_validate, /* 0 */
    764      NULL,                          /* 1 */
    765      gxv_LookupTable_fmt2_validate, /* 2 */
    766      NULL,                          /* 3 */
    767      gxv_LookupTable_fmt4_validate, /* 4 */
    768      NULL,                          /* 5 */
    769      gxv_LookupTable_fmt6_validate, /* 6 */
    770      NULL,                          /* 7 */
    771      gxv_LookupTable_fmt8_validate, /* 8 */
    772    };
    773 
    774    GXV_Validate_Func  func;
    775 
    776 
    777    GXV_NAME_ENTER( "LookupTable" );
    778 
    779    /* lookuptbl_head may be used in fmt4 transit function. */
    780    gxvalid->lookuptbl_head = table;
    781 
    782    /* format */
    783    GXV_LIMIT_CHECK( 2 );
    784    format = FT_NEXT_USHORT( p );
    785    GXV_TRACE(( " (format %d)\n", format ));
    786 
    787    if ( format > 8 )
    788      FT_INVALID_FORMAT;
    789 
    790    func = fmt_funcs_table[format];
    791    if ( !func )
    792      FT_INVALID_FORMAT;
    793 
    794    func( p, limit, gxvalid );
    795    p += gxvalid->subtable_length;
    796 
    797    gxvalid->subtable_length = (FT_ULong)( p - table );
    798 
    799    GXV_EXIT;
    800  }
    801 
    802 
    803  /*************************************************************************/
    804  /*************************************************************************/
    805  /*****                                                               *****/
    806  /*****                          Glyph ID                             *****/
    807  /*****                                                               *****/
    808  /*************************************************************************/
    809  /*************************************************************************/
    810 
    811  FT_LOCAL_DEF( FT_Int )
    812  gxv_glyphid_validate( FT_UShort      gid,
    813                        GXV_Validator  gxvalid )
    814  {
    815    FT_Face  face;
    816 
    817 
    818    if ( gid == 0xFFFFU )
    819    {
    820      GXV_EXIT;
    821      return 1;
    822    }
    823 
    824    face = gxvalid->face;
    825    if ( face->num_glyphs < gid )
    826    {
    827      GXV_TRACE(( " gxv_glyphid_check() gid overflow: num_glyphs %ld < %d\n",
    828                  face->num_glyphs, gid ));
    829      GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
    830    }
    831 
    832    return 0;
    833  }
    834 
    835 
    836  /*************************************************************************/
    837  /*************************************************************************/
    838  /*****                                                               *****/
    839  /*****                        CONTROL POINT                          *****/
    840  /*****                                                               *****/
    841  /*************************************************************************/
    842  /*************************************************************************/
    843 
    844  FT_LOCAL_DEF( void )
    845  gxv_ctlPoint_validate( FT_UShort      gid,
    846                         FT_UShort      ctl_point,
    847                         GXV_Validator  gxvalid )
    848  {
    849    FT_Face       face;
    850    FT_Error      error;
    851 
    852    FT_GlyphSlot  glyph;
    853    FT_Outline    outline;
    854    FT_UShort     n_points;
    855 
    856 
    857    face = gxvalid->face;
    858 
    859    error = FT_Load_Glyph( face,
    860                           gid,
    861                           FT_LOAD_NO_BITMAP | FT_LOAD_IGNORE_TRANSFORM );
    862    if ( error )
    863      FT_INVALID_GLYPH_ID;
    864 
    865    glyph    = face->glyph;
    866    outline  = glyph->outline;
    867    n_points = (FT_UShort)outline.n_points;
    868 
    869    if ( !( ctl_point < n_points ) )
    870      FT_INVALID_DATA;
    871  }
    872 
    873 
    874  /*************************************************************************/
    875  /*************************************************************************/
    876  /*****                                                               *****/
    877  /*****                          SFNT NAME                            *****/
    878  /*****                                                               *****/
    879  /*************************************************************************/
    880  /*************************************************************************/
    881 
    882  FT_LOCAL_DEF( void )
    883  gxv_sfntName_validate( FT_UShort      name_index,
    884                         FT_UShort      min_index,
    885                         FT_UShort      max_index,
    886                         GXV_Validator  gxvalid )
    887  {
    888    FT_SfntName  name;
    889    FT_UInt      i;
    890    FT_UInt      nnames;
    891 
    892 
    893    GXV_NAME_ENTER( "sfntName" );
    894 
    895    if ( name_index < min_index || max_index < name_index )
    896      FT_INVALID_FORMAT;
    897 
    898    nnames = FT_Get_Sfnt_Name_Count( gxvalid->face );
    899    for ( i = 0; i < nnames; i++ )
    900    {
    901      if ( FT_Get_Sfnt_Name( gxvalid->face, i, &name ) != FT_Err_Ok )
    902        continue;
    903 
    904      if ( name.name_id == name_index )
    905        goto Out;
    906    }
    907 
    908    GXV_TRACE(( "  nameIndex = %d (UNTITLED)\n", name_index ));
    909    FT_INVALID_DATA;
    910    goto Exit;  /* make compiler happy */
    911 
    912  Out:
    913    FT_TRACE1(( "  nameIndex = %d (", name_index ));
    914    GXV_TRACE_HEXDUMP_SFNTNAME( name );
    915    FT_TRACE1(( ")\n" ));
    916 
    917  Exit:
    918    GXV_EXIT;
    919  }
    920 
    921 
    922  /*************************************************************************/
    923  /*************************************************************************/
    924  /*****                                                               *****/
    925  /*****                          STATE TABLE                          *****/
    926  /*****                                                               *****/
    927  /*************************************************************************/
    928  /*************************************************************************/
    929 
    930  /* -------------------------- Class Table --------------------------- */
    931 
    932  /*
    933   * highestClass specifies how many classes are defined in this
    934   * Class Subtable.  Apple spec does not mention whether undefined
    935   * holes in the class (e.g.: 0-3 are predefined, 4 is unused, 5 is used)
    936   * are permitted.  At present, holes in a defined class are not checked.
    937   *   -- suzuki toshiya <mpsuzuki@hiroshima-u.ac.jp>
    938   */
    939 
    940  static void
    941  gxv_ClassTable_validate( FT_Bytes       table,
    942                           FT_UShort*     length_p,
    943                           FT_UShort      stateSize,
    944                           FT_Byte*       maxClassID_p,
    945                           GXV_Validator  gxvalid )
    946  {
    947    FT_Bytes   p     = table;
    948    FT_Bytes   limit = table + *length_p;
    949    FT_UShort  firstGlyph;
    950    FT_UShort  nGlyphs;
    951 
    952 
    953    GXV_NAME_ENTER( "ClassTable" );
    954 
    955    *maxClassID_p = 3;  /* Classes 0, 2, and 3 are predefined */
    956 
    957    GXV_LIMIT_CHECK( 2 + 2 );
    958    firstGlyph = FT_NEXT_USHORT( p );
    959    nGlyphs    = FT_NEXT_USHORT( p );
    960 
    961    GXV_TRACE(( " (firstGlyph = %d, nGlyphs = %d)\n", firstGlyph, nGlyphs ));
    962 
    963    if ( !nGlyphs )
    964      goto Out;
    965 
    966    gxv_glyphid_validate( (FT_UShort)( firstGlyph + nGlyphs ), gxvalid );
    967 
    968    {
    969      FT_Byte    nGlyphInClass[256];
    970      FT_Byte    classID;
    971      FT_UShort  i;
    972 
    973 
    974      FT_MEM_ZERO( nGlyphInClass, 256 );
    975 
    976 
    977      for ( i = 0; i < nGlyphs; i++ )
    978      {
    979        GXV_LIMIT_CHECK( 1 );
    980        classID = FT_NEXT_BYTE( p );
    981        switch ( classID )
    982        {
    983          /* following classes should not appear in class array */
    984        case 0:             /* end of text */
    985        case 2:             /* out of bounds */
    986        case 3:             /* end of line */
    987          FT_INVALID_DATA;
    988          break;
    989 
    990        case 1:             /* out of bounds */
    991        default:            /* user-defined: 4 - ( stateSize - 1 ) */
    992          if ( classID >= stateSize )
    993            FT_INVALID_DATA;   /* assign glyph to undefined state */
    994 
    995          nGlyphInClass[classID]++;
    996          break;
    997        }
    998      }
    999      *length_p = (FT_UShort)( p - table );
   1000 
   1001      /* scan max ClassID in use */
   1002      for ( i = 0; i < stateSize; i++ )
   1003        if ( ( 3 < i ) && ( nGlyphInClass[i] > 0 ) )
   1004          *maxClassID_p = (FT_Byte)i;  /* XXX: Check Range? */
   1005    }
   1006 
   1007  Out:
   1008    GXV_TRACE(( "Declared stateSize=0x%02x, Used maxClassID=0x%02x\n",
   1009                stateSize, *maxClassID_p ));
   1010    GXV_EXIT;
   1011  }
   1012 
   1013 
   1014  /* --------------------------- State Array ----------------------------- */
   1015 
   1016  static void
   1017  gxv_StateArray_validate( FT_Bytes       table,
   1018                           FT_UShort*     length_p,
   1019                           FT_Byte        maxClassID,
   1020                           FT_UShort      stateSize,
   1021                           FT_Byte*       maxState_p,
   1022                           FT_Byte*       maxEntry_p,
   1023                           GXV_Validator  gxvalid )
   1024  {
   1025    FT_Bytes  p     = table;
   1026    FT_Bytes  limit = table + *length_p;
   1027    FT_Byte   clazz;
   1028    FT_Byte   entry;
   1029 
   1030    FT_UNUSED( stateSize ); /* for the non-debugging case */
   1031 
   1032 
   1033    GXV_NAME_ENTER( "StateArray" );
   1034 
   1035    GXV_TRACE(( "parse %d bytes by stateSize=%d maxClassID=%d\n",
   1036                (int)( *length_p ), stateSize, (int)maxClassID ));
   1037 
   1038    /*
   1039     * 2 states are predefined and must be described in StateArray:
   1040     * state 0 (start of text), 1 (start of line)
   1041     */
   1042    GXV_LIMIT_CHECK( ( 1 + maxClassID ) * 2 );
   1043 
   1044    *maxState_p = 0;
   1045    *maxEntry_p = 0;
   1046 
   1047    /* read if enough to read another state */
   1048    while ( p + ( 1 + maxClassID ) <= limit )
   1049    {
   1050      (*maxState_p)++;
   1051      for ( clazz = 0; clazz <= maxClassID; clazz++ )
   1052      {
   1053        entry = FT_NEXT_BYTE( p );
   1054        *maxEntry_p = (FT_Byte)FT_MAX( *maxEntry_p, entry );
   1055      }
   1056    }
   1057    GXV_TRACE(( "parsed: maxState=%d, maxEntry=%d\n",
   1058                *maxState_p, *maxEntry_p ));
   1059 
   1060    *length_p = (FT_UShort)( p - table );
   1061 
   1062    GXV_EXIT;
   1063  }
   1064 
   1065 
   1066  /* --------------------------- Entry Table ----------------------------- */
   1067 
   1068  static void
   1069  gxv_EntryTable_validate( FT_Bytes       table,
   1070                           FT_UShort*     length_p,
   1071                           FT_Byte        maxEntry,
   1072                           FT_UShort      stateArray,
   1073                           FT_UShort      stateArray_length,
   1074                           FT_Byte        maxClassID,
   1075                           FT_Bytes       statetable_table,
   1076                           FT_Bytes       statetable_limit,
   1077                           GXV_Validator  gxvalid )
   1078  {
   1079    FT_Bytes  p     = table;
   1080    FT_Bytes  limit = table + *length_p;
   1081    FT_Byte   entry;
   1082    FT_Byte   state;
   1083    FT_Int    entrySize = 2 + 2 + GXV_GLYPHOFFSET_SIZE( statetable );
   1084 
   1085    GXV_XStateTable_GlyphOffsetDesc  glyphOffset;
   1086 
   1087 
   1088    GXV_NAME_ENTER( "EntryTable" );
   1089 
   1090    GXV_TRACE(( "maxEntry=%d entrySize=%d\n", maxEntry, entrySize ));
   1091 
   1092    if ( ( maxEntry + 1 ) * entrySize > *length_p )
   1093    {
   1094      GXV_SET_ERR_IF_PARANOID( FT_INVALID_TOO_SHORT );
   1095 
   1096      /* ftxvalidator and FontValidator both warn and continue */
   1097      maxEntry = (FT_Byte)( *length_p / entrySize - 1 );
   1098      GXV_TRACE(( "too large maxEntry, shrinking to %d fit EntryTable length\n",
   1099                  maxEntry ));
   1100    }
   1101 
   1102    for ( entry = 0; entry <= maxEntry; entry++ )
   1103    {
   1104      FT_UShort  newState;
   1105      FT_UShort  flags;
   1106 
   1107 
   1108      GXV_LIMIT_CHECK( 2 + 2 );
   1109      newState = FT_NEXT_USHORT( p );
   1110      flags    = FT_NEXT_USHORT( p );
   1111 
   1112 
   1113      if ( newState < stateArray                     ||
   1114           stateArray + stateArray_length < newState )
   1115      {
   1116        GXV_TRACE(( " newState offset 0x%04x is out of stateArray\n",
   1117                    newState ));
   1118        GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
   1119        continue;
   1120      }
   1121 
   1122      if ( 0 != ( ( newState - stateArray ) % ( 1 + maxClassID ) ) )
   1123      {
   1124        GXV_TRACE(( " newState offset 0x%04x is not aligned to %d-classes\n",
   1125                    newState,  1 + maxClassID ));
   1126        GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
   1127        continue;
   1128      }
   1129 
   1130      state = (FT_Byte)( ( newState - stateArray ) / ( 1 + maxClassID ) );
   1131 
   1132      switch ( GXV_GLYPHOFFSET_FMT( statetable ) )
   1133      {
   1134      case GXV_GLYPHOFFSET_NONE:
   1135        glyphOffset.uc = 0;  /* make compiler happy */
   1136        break;
   1137 
   1138      case GXV_GLYPHOFFSET_UCHAR:
   1139        glyphOffset.uc = FT_NEXT_BYTE( p );
   1140        break;
   1141 
   1142      case GXV_GLYPHOFFSET_CHAR:
   1143        glyphOffset.c = FT_NEXT_CHAR( p );
   1144        break;
   1145 
   1146      case GXV_GLYPHOFFSET_USHORT:
   1147        glyphOffset.u = FT_NEXT_USHORT( p );
   1148        break;
   1149 
   1150      case GXV_GLYPHOFFSET_SHORT:
   1151        glyphOffset.s = FT_NEXT_SHORT( p );
   1152        break;
   1153 
   1154      case GXV_GLYPHOFFSET_ULONG:
   1155        glyphOffset.ul = FT_NEXT_ULONG( p );
   1156        break;
   1157 
   1158      case GXV_GLYPHOFFSET_LONG:
   1159        glyphOffset.l = FT_NEXT_LONG( p );
   1160        break;
   1161      }
   1162 
   1163      if ( gxvalid->statetable.entry_validate_func )
   1164        gxvalid->statetable.entry_validate_func( state,
   1165                                                 flags,
   1166                                                 &glyphOffset,
   1167                                                 statetable_table,
   1168                                                 statetable_limit,
   1169                                                 gxvalid );
   1170    }
   1171 
   1172    *length_p = (FT_UShort)( p - table );
   1173 
   1174    GXV_EXIT;
   1175  }
   1176 
   1177 
   1178  /* =========================== State Table ============================= */
   1179 
   1180  FT_LOCAL_DEF( void )
   1181  gxv_StateTable_subtable_setup( FT_UShort      table_size,
   1182                                 FT_UShort      classTable,
   1183                                 FT_UShort      stateArray,
   1184                                 FT_UShort      entryTable,
   1185                                 FT_UShort*     classTable_length_p,
   1186                                 FT_UShort*     stateArray_length_p,
   1187                                 FT_UShort*     entryTable_length_p,
   1188                                 GXV_Validator  gxvalid )
   1189  {
   1190    FT_UShort   o[3];
   1191    FT_UShort*  l[3];
   1192    FT_UShort   buff[4];
   1193 
   1194 
   1195    o[0] = classTable;
   1196    o[1] = stateArray;
   1197    o[2] = entryTable;
   1198    l[0] = classTable_length_p;
   1199    l[1] = stateArray_length_p;
   1200    l[2] = entryTable_length_p;
   1201 
   1202    gxv_set_length_by_ushort_offset( o, l, buff, 3, table_size, gxvalid );
   1203  }
   1204 
   1205 
   1206  FT_LOCAL_DEF( void )
   1207  gxv_StateTable_validate( FT_Bytes       table,
   1208                           FT_Bytes       limit,
   1209                           GXV_Validator  gxvalid )
   1210  {
   1211    FT_UShort   stateSize;
   1212    FT_UShort   classTable;     /* offset to Class(Sub)Table */
   1213    FT_UShort   stateArray;     /* offset to StateArray */
   1214    FT_UShort   entryTable;     /* offset to EntryTable */
   1215 
   1216    FT_UShort   classTable_length;
   1217    FT_UShort   stateArray_length;
   1218    FT_UShort   entryTable_length;
   1219    FT_Byte     maxClassID;
   1220    FT_Byte     maxState;
   1221    FT_Byte     maxEntry;
   1222 
   1223    GXV_StateTable_Subtable_Setup_Func  setup_func;
   1224 
   1225    FT_Bytes    p = table;
   1226 
   1227 
   1228    GXV_NAME_ENTER( "StateTable" );
   1229 
   1230    GXV_TRACE(( "StateTable header\n" ));
   1231 
   1232    GXV_LIMIT_CHECK( 2 + 2 + 2 + 2 );
   1233    stateSize  = FT_NEXT_USHORT( p );
   1234    classTable = FT_NEXT_USHORT( p );
   1235    stateArray = FT_NEXT_USHORT( p );
   1236    entryTable = FT_NEXT_USHORT( p );
   1237 
   1238    GXV_TRACE(( "stateSize=0x%04x\n", stateSize ));
   1239    GXV_TRACE(( "offset to classTable=0x%04x\n", classTable ));
   1240    GXV_TRACE(( "offset to stateArray=0x%04x\n", stateArray ));
   1241    GXV_TRACE(( "offset to entryTable=0x%04x\n", entryTable ));
   1242 
   1243    if ( stateSize > 0xFF )
   1244      FT_INVALID_DATA;
   1245 
   1246    if ( gxvalid->statetable.optdata_load_func )
   1247      gxvalid->statetable.optdata_load_func( p, limit, gxvalid );
   1248 
   1249    if ( gxvalid->statetable.subtable_setup_func )
   1250      setup_func = gxvalid->statetable.subtable_setup_func;
   1251    else
   1252      setup_func = gxv_StateTable_subtable_setup;
   1253 
   1254    setup_func( (FT_UShort)( limit - table ),
   1255                classTable,
   1256                stateArray,
   1257                entryTable,
   1258                &classTable_length,
   1259                &stateArray_length,
   1260                &entryTable_length,
   1261                gxvalid );
   1262 
   1263    GXV_TRACE(( "StateTable Subtables\n" ));
   1264 
   1265    if ( classTable != 0 )
   1266      gxv_ClassTable_validate( table + classTable,
   1267                               &classTable_length,
   1268                               stateSize,
   1269                               &maxClassID,
   1270                               gxvalid );
   1271    else
   1272      maxClassID = (FT_Byte)( stateSize - 1 );
   1273 
   1274    if ( stateArray != 0 )
   1275      gxv_StateArray_validate( table + stateArray,
   1276                               &stateArray_length,
   1277                               maxClassID,
   1278                               stateSize,
   1279                               &maxState,
   1280                               &maxEntry,
   1281                               gxvalid );
   1282    else
   1283    {
   1284 #if 0
   1285      maxState = 1;     /* 0:start of text, 1:start of line are predefined */
   1286 #endif
   1287      maxEntry = 0;
   1288    }
   1289 
   1290    if ( maxEntry > 0 && entryTable == 0 )
   1291      FT_INVALID_OFFSET;
   1292 
   1293    if ( entryTable != 0 )
   1294      gxv_EntryTable_validate( table + entryTable,
   1295                               &entryTable_length,
   1296                               maxEntry,
   1297                               stateArray,
   1298                               stateArray_length,
   1299                               maxClassID,
   1300                               table,
   1301                               limit,
   1302                               gxvalid );
   1303 
   1304    GXV_EXIT;
   1305  }
   1306 
   1307 
   1308  /* ================= eXtended State Table (for morx) =================== */
   1309 
   1310  FT_LOCAL_DEF( void )
   1311  gxv_XStateTable_subtable_setup( FT_ULong       table_size,
   1312                                  FT_ULong       classTable,
   1313                                  FT_ULong       stateArray,
   1314                                  FT_ULong       entryTable,
   1315                                  FT_ULong*      classTable_length_p,
   1316                                  FT_ULong*      stateArray_length_p,
   1317                                  FT_ULong*      entryTable_length_p,
   1318                                  GXV_Validator  gxvalid )
   1319  {
   1320    FT_ULong   o[3];
   1321    FT_ULong*  l[3];
   1322    FT_ULong   buff[4];
   1323 
   1324 
   1325    o[0] = classTable;
   1326    o[1] = stateArray;
   1327    o[2] = entryTable;
   1328    l[0] = classTable_length_p;
   1329    l[1] = stateArray_length_p;
   1330    l[2] = entryTable_length_p;
   1331 
   1332    gxv_set_length_by_ulong_offset( o, l, buff, 3, table_size, gxvalid );
   1333  }
   1334 
   1335 
   1336  static void
   1337  gxv_XClassTable_lookupval_validate( FT_UShort            glyph,
   1338                                      GXV_LookupValueCPtr  value_p,
   1339                                      GXV_Validator        gxvalid )
   1340  {
   1341    FT_UNUSED( glyph );
   1342 
   1343    if ( value_p->u >= gxvalid->xstatetable.nClasses )
   1344      FT_INVALID_DATA;
   1345    if ( value_p->u > gxvalid->xstatetable.maxClassID )
   1346      gxvalid->xstatetable.maxClassID = value_p->u;
   1347  }
   1348 
   1349 
   1350  /*
   1351    +===============+ --------+
   1352    | lookup header |         |
   1353    +===============+         |
   1354    | BinSrchHeader |         |
   1355    +===============+         |
   1356    | lastGlyph[0]  |         |
   1357    +---------------+         |
   1358    | firstGlyph[0] |         |    head of lookup table
   1359    +---------------+         |             +
   1360    | offset[0]     |    ->   |          offset            [byte]
   1361    +===============+         |             +
   1362    | lastGlyph[1]  |         | (glyphID - firstGlyph) * 2 [byte]
   1363    +---------------+         |
   1364    | firstGlyph[1] |         |
   1365    +---------------+         |
   1366    | offset[1]     |         |
   1367    +===============+         |
   1368                              |
   1369     ....                     |
   1370                              |
   1371    16bit value array         |
   1372    +===============+         |
   1373    |     value     | <-------+
   1374     ....
   1375  */
   1376  static GXV_LookupValueDesc
   1377  gxv_XClassTable_lookupfmt4_transit( FT_UShort            relative_gindex,
   1378                                      GXV_LookupValueCPtr  base_value_p,
   1379                                      FT_Bytes             lookuptbl_limit,
   1380                                      GXV_Validator        gxvalid )
   1381  {
   1382    FT_Bytes             p;
   1383    FT_Bytes             limit;
   1384    FT_UShort            offset;
   1385    GXV_LookupValueDesc  value;
   1386 
   1387    /* XXX: check range? */
   1388    offset = (FT_UShort)( base_value_p->u +
   1389                          relative_gindex * sizeof ( FT_UShort ) );
   1390 
   1391    p     = gxvalid->lookuptbl_head + offset;
   1392    limit = lookuptbl_limit;
   1393 
   1394    GXV_LIMIT_CHECK ( 2 );
   1395    value.u = FT_NEXT_USHORT( p );
   1396 
   1397    return value;
   1398  }
   1399 
   1400 
   1401  static void
   1402  gxv_XStateArray_validate( FT_Bytes       table,
   1403                            FT_ULong*      length_p,
   1404                            FT_UShort      maxClassID,
   1405                            FT_ULong       stateSize,
   1406                            FT_UShort*     maxState_p,
   1407                            FT_UShort*     maxEntry_p,
   1408                            GXV_Validator  gxvalid )
   1409  {
   1410    FT_Bytes   p = table;
   1411    FT_Bytes   limit = table + *length_p;
   1412    FT_UShort  clazz;
   1413    FT_UShort  entry;
   1414 
   1415    FT_UNUSED( stateSize ); /* for the non-debugging case */
   1416 
   1417 
   1418    GXV_NAME_ENTER( "XStateArray" );
   1419 
   1420    GXV_TRACE(( "parse % 3d bytes by stateSize=% 3d maxClassID=% 3d\n",
   1421                (int)( *length_p ), (int)stateSize, (int)maxClassID ));
   1422 
   1423    /*
   1424     * 2 states are predefined and must be described:
   1425     * state 0 (start of text), 1 (start of line)
   1426     */
   1427    GXV_LIMIT_CHECK( ( 1 + maxClassID ) * 2 * 2 );
   1428 
   1429    *maxState_p = 0;
   1430    *maxEntry_p = 0;
   1431 
   1432    /* read if enough to read another state */
   1433    while ( p + ( ( 1 + maxClassID ) * 2 ) <= limit )
   1434    {
   1435      (*maxState_p)++;
   1436      for ( clazz = 0; clazz <= maxClassID; clazz++ )
   1437      {
   1438        entry = FT_NEXT_USHORT( p );
   1439        *maxEntry_p = (FT_UShort)FT_MAX( *maxEntry_p, entry );
   1440      }
   1441    }
   1442    GXV_TRACE(( "parsed: maxState=%d, maxEntry=%d\n",
   1443                *maxState_p, *maxEntry_p ));
   1444 
   1445    *length_p = (FT_ULong)( p - table );
   1446 
   1447    GXV_EXIT;
   1448  }
   1449 
   1450 
   1451  static void
   1452  gxv_XEntryTable_validate( FT_Bytes       table,
   1453                            FT_ULong*      length_p,
   1454                            FT_UShort      maxEntry,
   1455                            FT_ULong       stateArray_length,
   1456                            FT_UShort      maxClassID,
   1457                            FT_Bytes       xstatetable_table,
   1458                            FT_Bytes       xstatetable_limit,
   1459                            GXV_Validator  gxvalid )
   1460  {
   1461    FT_Bytes   p = table;
   1462    FT_Bytes   limit = table + *length_p;
   1463    FT_UShort  entry;
   1464    FT_UShort  state;
   1465    FT_Int     entrySize = 2 + 2 + GXV_GLYPHOFFSET_SIZE( xstatetable );
   1466 
   1467 
   1468    GXV_NAME_ENTER( "XEntryTable" );
   1469    GXV_TRACE(( "maxEntry=%d entrySize=%d\n", maxEntry, entrySize ));
   1470 
   1471    if ( ( p + ( maxEntry + 1 ) * entrySize ) > limit )
   1472      FT_INVALID_TOO_SHORT;
   1473 
   1474    for (entry = 0; entry <= maxEntry; entry++ )
   1475    {
   1476      FT_UShort                        newState_idx;
   1477      FT_UShort                        flags;
   1478      GXV_XStateTable_GlyphOffsetDesc  glyphOffset;
   1479 
   1480 
   1481      GXV_LIMIT_CHECK( 2 + 2 );
   1482      newState_idx = FT_NEXT_USHORT( p );
   1483      flags        = FT_NEXT_USHORT( p );
   1484 
   1485      if ( stateArray_length < (FT_ULong)( newState_idx * 2 ) )
   1486      {
   1487        GXV_TRACE(( "  newState index 0x%04x points out of stateArray\n",
   1488                    newState_idx ));
   1489        GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
   1490      }
   1491 
   1492      state = (FT_UShort)( newState_idx / ( 1 + maxClassID ) );
   1493      if ( 0 != ( newState_idx % ( 1 + maxClassID ) ) )
   1494      {
   1495        FT_TRACE4(( "-> new state = %d (supposed)\n",
   1496                    state ));
   1497        FT_TRACE4(( "but newState index 0x%04x"
   1498                    " is not aligned to %d-classes\n",
   1499                    newState_idx, 1 + maxClassID ));
   1500        GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
   1501      }
   1502 
   1503      switch ( GXV_GLYPHOFFSET_FMT( xstatetable ) )
   1504      {
   1505      case GXV_GLYPHOFFSET_NONE:
   1506        glyphOffset.uc = 0; /* make compiler happy */
   1507        break;
   1508 
   1509      case GXV_GLYPHOFFSET_UCHAR:
   1510        glyphOffset.uc = FT_NEXT_BYTE( p );
   1511        break;
   1512 
   1513      case GXV_GLYPHOFFSET_CHAR:
   1514        glyphOffset.c = FT_NEXT_CHAR( p );
   1515        break;
   1516 
   1517      case GXV_GLYPHOFFSET_USHORT:
   1518        glyphOffset.u = FT_NEXT_USHORT( p );
   1519        break;
   1520 
   1521      case GXV_GLYPHOFFSET_SHORT:
   1522        glyphOffset.s = FT_NEXT_SHORT( p );
   1523        break;
   1524 
   1525      case GXV_GLYPHOFFSET_ULONG:
   1526        glyphOffset.ul = FT_NEXT_ULONG( p );
   1527        break;
   1528 
   1529      case GXV_GLYPHOFFSET_LONG:
   1530        glyphOffset.l = FT_NEXT_LONG( p );
   1531        break;
   1532 
   1533      default:
   1534        GXV_SET_ERR_IF_PARANOID( FT_INVALID_FORMAT );
   1535        goto Exit;
   1536      }
   1537 
   1538      if ( gxvalid->xstatetable.entry_validate_func )
   1539        gxvalid->xstatetable.entry_validate_func( state,
   1540                                                  flags,
   1541                                                  &glyphOffset,
   1542                                                  xstatetable_table,
   1543                                                  xstatetable_limit,
   1544                                                  gxvalid );
   1545    }
   1546 
   1547  Exit:
   1548    *length_p = (FT_ULong)( p - table );
   1549 
   1550    GXV_EXIT;
   1551  }
   1552 
   1553 
   1554  FT_LOCAL_DEF( void )
   1555  gxv_XStateTable_validate( FT_Bytes       table,
   1556                            FT_Bytes       limit,
   1557                            GXV_Validator  gxvalid )
   1558  {
   1559    /* StateHeader members */
   1560    FT_ULong   classTable;      /* offset to Class(Sub)Table */
   1561    FT_ULong   stateArray;      /* offset to StateArray */
   1562    FT_ULong   entryTable;      /* offset to EntryTable */
   1563 
   1564    FT_ULong   classTable_length;
   1565    FT_ULong   stateArray_length;
   1566    FT_ULong   entryTable_length;
   1567    FT_UShort  maxState;
   1568    FT_UShort  maxEntry;
   1569 
   1570    GXV_XStateTable_Subtable_Setup_Func  setup_func;
   1571 
   1572    FT_Bytes   p = table;
   1573 
   1574 
   1575    GXV_NAME_ENTER( "XStateTable" );
   1576 
   1577    GXV_TRACE(( "XStateTable header\n" ));
   1578 
   1579    GXV_LIMIT_CHECK( 4 + 4 + 4 + 4 );
   1580    gxvalid->xstatetable.nClasses = FT_NEXT_ULONG( p );
   1581    classTable = FT_NEXT_ULONG( p );
   1582    stateArray = FT_NEXT_ULONG( p );
   1583    entryTable = FT_NEXT_ULONG( p );
   1584 
   1585    GXV_TRACE(( "nClasses =0x%08lx\n", gxvalid->xstatetable.nClasses ));
   1586    GXV_TRACE(( "offset to classTable=0x%08lx\n", classTable ));
   1587    GXV_TRACE(( "offset to stateArray=0x%08lx\n", stateArray ));
   1588    GXV_TRACE(( "offset to entryTable=0x%08lx\n", entryTable ));
   1589 
   1590    if ( gxvalid->xstatetable.nClasses > 0xFFFFU )
   1591      FT_INVALID_DATA;
   1592 
   1593    GXV_TRACE(( "StateTable Subtables\n" ));
   1594 
   1595    if ( gxvalid->xstatetable.optdata_load_func )
   1596      gxvalid->xstatetable.optdata_load_func( p, limit, gxvalid );
   1597 
   1598    if ( gxvalid->xstatetable.subtable_setup_func )
   1599      setup_func = gxvalid->xstatetable.subtable_setup_func;
   1600    else
   1601      setup_func = gxv_XStateTable_subtable_setup;
   1602 
   1603    setup_func( (FT_ULong)( limit - table ),
   1604                classTable,
   1605                stateArray,
   1606                entryTable,
   1607                &classTable_length,
   1608                &stateArray_length,
   1609                &entryTable_length,
   1610                gxvalid );
   1611 
   1612    if ( classTable != 0 )
   1613    {
   1614      gxvalid->xstatetable.maxClassID = 0;
   1615      gxvalid->lookupval_sign         = GXV_LOOKUPVALUE_UNSIGNED;
   1616      gxvalid->lookupval_func         = gxv_XClassTable_lookupval_validate;
   1617      gxvalid->lookupfmt4_trans       = gxv_XClassTable_lookupfmt4_transit;
   1618      gxv_LookupTable_validate( table + classTable,
   1619                                table + classTable + classTable_length,
   1620                                gxvalid );
   1621 #if 0
   1622      if ( gxvalid->subtable_length < classTable_length )
   1623        classTable_length = gxvalid->subtable_length;
   1624 #endif
   1625    }
   1626    else
   1627    {
   1628      /* XXX: check range? */
   1629      gxvalid->xstatetable.maxClassID =
   1630        (FT_UShort)( gxvalid->xstatetable.nClasses - 1 );
   1631    }
   1632 
   1633    if ( stateArray != 0 )
   1634      gxv_XStateArray_validate( table + stateArray,
   1635                                &stateArray_length,
   1636                                gxvalid->xstatetable.maxClassID,
   1637                                gxvalid->xstatetable.nClasses,
   1638                                &maxState,
   1639                                &maxEntry,
   1640                                gxvalid );
   1641    else
   1642    {
   1643 #if 0
   1644      maxState = 1; /* 0:start of text, 1:start of line are predefined */
   1645 #endif
   1646      maxEntry = 0;
   1647    }
   1648 
   1649    if ( maxEntry > 0 && entryTable == 0 )
   1650      FT_INVALID_OFFSET;
   1651 
   1652    if ( entryTable != 0 )
   1653      gxv_XEntryTable_validate( table + entryTable,
   1654                                &entryTable_length,
   1655                                maxEntry,
   1656                                stateArray_length,
   1657                                gxvalid->xstatetable.maxClassID,
   1658                                table,
   1659                                limit,
   1660                                gxvalid );
   1661 
   1662    GXV_EXIT;
   1663  }
   1664 
   1665 
   1666  /*************************************************************************/
   1667  /*************************************************************************/
   1668  /*****                                                               *****/
   1669  /*****                        Table overlapping                      *****/
   1670  /*****                                                               *****/
   1671  /*************************************************************************/
   1672  /*************************************************************************/
   1673 
   1674  static int
   1675  gxv_compare_ranges( FT_Bytes  table1_start,
   1676                      FT_ULong  table1_length,
   1677                      FT_Bytes  table2_start,
   1678                      FT_ULong  table2_length )
   1679  {
   1680    if ( table1_start == table2_start )
   1681    {
   1682      if ( ( table1_length == 0 || table2_length == 0 ) )
   1683        goto Out;
   1684    }
   1685    else if ( table1_start < table2_start )
   1686    {
   1687      if ( ( table1_start + table1_length ) <= table2_start )
   1688        goto Out;
   1689    }
   1690    else if ( table1_start > table2_start )
   1691    {
   1692      if ( ( table1_start >= table2_start + table2_length ) )
   1693        goto Out;
   1694    }
   1695    return 1;
   1696 
   1697  Out:
   1698    return 0;
   1699  }
   1700 
   1701 
   1702  FT_LOCAL_DEF( void )
   1703  gxv_odtect_add_range( FT_Bytes          start,
   1704                        FT_ULong          length,
   1705                        const FT_String*  name,
   1706                        GXV_odtect_Range  odtect )
   1707  {
   1708    odtect->range[odtect->nRanges].start  = start;
   1709    odtect->range[odtect->nRanges].length = length;
   1710    odtect->range[odtect->nRanges].name   = (FT_String*)name;
   1711    odtect->nRanges++;
   1712  }
   1713 
   1714 
   1715  FT_LOCAL_DEF( void )
   1716  gxv_odtect_validate( GXV_odtect_Range  odtect,
   1717                       GXV_Validator     gxvalid )
   1718  {
   1719    FT_UInt  i, j;
   1720 
   1721 
   1722    GXV_NAME_ENTER( "check overlap among multi ranges" );
   1723 
   1724    for ( i = 0; i < odtect->nRanges; i++ )
   1725      for ( j = 0; j < i; j++ )
   1726        if ( 0 != gxv_compare_ranges( odtect->range[i].start,
   1727                                      odtect->range[i].length,
   1728                                      odtect->range[j].start,
   1729                                      odtect->range[j].length ) )
   1730        {
   1731 #ifdef FT_DEBUG_LEVEL_TRACE
   1732          if ( odtect->range[i].name || odtect->range[j].name )
   1733            GXV_TRACE(( "found overlap between range %u and range %u\n",
   1734                        i, j ));
   1735          else
   1736            GXV_TRACE(( "found overlap between `%s' and `%s\'\n",
   1737                        odtect->range[i].name,
   1738                        odtect->range[j].name ));
   1739 #endif
   1740          FT_INVALID_OFFSET;
   1741        }
   1742 
   1743    GXV_EXIT;
   1744  }
   1745 
   1746 
   1747 /* END */