thirdparty/freetype-2.3.12/src/otvalid/otvcommn.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  otvcommn.c                                                             */
   4 /*                                                                         */
   5 /*    OpenType common tables validation (body).                            */
   6 /*                                                                         */
   7 /*  Copyright 2004, 2005, 2006, 2007 by                                    */
   8 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
   9 /*                                                                         */
  10 /*  This file is part of the FreeType project, and may only be used,       */
  11 /*  modified, and distributed under the terms of the FreeType project      */
  12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  13 /*  this file you indicate that you have read the license and              */
  14 /*  understand and accept it fully.                                        */
  15 /*                                                                         */
  16 /***************************************************************************/
  17
  18
  19 #include "otvcommn.h"
  20
  21
  22   /*************************************************************************/
  23   /*                                                                       */
  24   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  25   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  26   /* messages during execution.                                            */
  27   /*                                                                       */
  28 #undef  FT_COMPONENT
  29 #define FT_COMPONENT  trace_otvcommon
  30
  31
  32   /*************************************************************************/
  33   /*************************************************************************/
  34   /*****                                                               *****/
  35   /*****                       COVERAGE TABLE                          *****/
  36   /*****                                                               *****/
  37   /*************************************************************************/
  38   /*************************************************************************/
  39
  40   FT_LOCAL_DEF( void )
  41   otv_Coverage_validate( FT_Bytes       table,
  42                          OTV_Validator  valid,
  43                          FT_Int         expected_count )
  44   {
  45     FT_Bytes  p = table;
  46     FT_UInt   CoverageFormat;
  47     FT_UInt   total = 0;
  48
  49
  50     OTV_NAME_ENTER( "Coverage" );
  51
  52     OTV_LIMIT_CHECK( 4 );
  53     CoverageFormat = FT_NEXT_USHORT( p );
  54
  55     OTV_TRACE(( " (format %d)\n", CoverageFormat ));
  56
  57     switch ( CoverageFormat )
  58     {
  59     case 1:     /* CoverageFormat1 */
  60       {
  61         FT_UInt  GlyphCount;
  62         FT_UInt  i;
  63
  64
  65         GlyphCount = FT_NEXT_USHORT( p );
  66
  67         OTV_TRACE(( " (GlyphCount = %d)\n", GlyphCount ));
  68
  69         OTV_LIMIT_CHECK( GlyphCount * 2 );        /* GlyphArray */
  70
  71         for ( i = 0; i < GlyphCount; ++i )
  72         {
  73           FT_UInt  gid;
  74
  75
  76           gid = FT_NEXT_USHORT( p );
  77           if ( gid >= valid->glyph_count )
  78             FT_INVALID_GLYPH_ID;
  79         }
  80
  81         total = GlyphCount;
  82       }
  83       break;
  84
  85     case 2:     /* CoverageFormat2 */
  86       {
  87         FT_UInt  n, RangeCount;
  88         FT_UInt  Start, End, StartCoverageIndex, last = 0;
  89
  90
  91         RangeCount = FT_NEXT_USHORT( p );
  92
  93         OTV_TRACE(( " (RangeCount = %d)\n", RangeCount ));
  94
  95         OTV_LIMIT_CHECK( RangeCount * 6 );
  96
  97         /* RangeRecord */
  98         for ( n = 0; n < RangeCount; n++ )
  99         {
 100           Start              = FT_NEXT_USHORT( p );
 101           End                = FT_NEXT_USHORT( p );
 102           StartCoverageIndex = FT_NEXT_USHORT( p );
 103
 104           if ( Start > End || StartCoverageIndex != total )
 105             FT_INVALID_DATA;
 106
 107           if ( End >= valid->glyph_count )
 108             FT_INVALID_GLYPH_ID;
 109
 110           if ( n > 0 && Start <= last )
 111             FT_INVALID_DATA;
 112
 113           total += End - Start + 1;
 114           last   = End;
 115         }
 116       }
 117       break;
 118
 119     default:
 120       FT_INVALID_FORMAT;
 121     }
 122
 123     /* Generally, a coverage table offset has an associated count field.  */
 124     /* The number of glyphs in the table should match this field.  If     */
 125     /* there is no associated count, a value of -1 tells us not to check. */
 126     if ( expected_count != -1 && (FT_UInt)expected_count != total )
 127       FT_INVALID_DATA;
 128
 129     OTV_EXIT;
 130   }
 131
 132
 133   FT_LOCAL_DEF( FT_UInt )
 134   otv_Coverage_get_first( FT_Bytes  table )
 135   {
 136     FT_Bytes  p = table;
 137
 138
 139     p += 4;     /* skip CoverageFormat and Glyph/RangeCount */
 140
 141     return FT_NEXT_USHORT( p );
 142   }
 143
 144
 145   FT_LOCAL_DEF( FT_UInt )
 146   otv_Coverage_get_last( FT_Bytes  table )
 147   {
 148     FT_Bytes  p = table;
 149     FT_UInt   CoverageFormat = FT_NEXT_USHORT( p );
 150     FT_UInt   count          = FT_NEXT_USHORT( p );     /* Glyph/RangeCount */
 151     FT_UInt   result = 0;
 152
 153
 154     switch ( CoverageFormat )
 155     {
 156     case 1:
 157       p += ( count - 1 ) * 2;
 158       result = FT_NEXT_USHORT( p );
 159       break;
 160
 161     case 2:
 162       p += ( count - 1 ) * 6 + 2;
 163       result = FT_NEXT_USHORT( p );
 164       break;
 165
 166     default:
 167       ;
 168     }
 169
 170     return result;
 171   }
 172
 173
 174   FT_LOCAL_DEF( FT_UInt )
 175   otv_Coverage_get_count( FT_Bytes  table )
 176   {
 177     FT_Bytes  p              = table;
 178     FT_UInt   CoverageFormat = FT_NEXT_USHORT( p );
 179     FT_UInt   count          = FT_NEXT_USHORT( p );     /* Glyph/RangeCount */
 180     FT_UInt   result         = 0;
 181
 182
 183     switch ( CoverageFormat )
 184     {
 185     case 1:
 186       return count;
 187
 188     case 2:
 189       {
 190         FT_UInt  Start, End;
 191
 192
 193         for ( ; count > 0; count-- )
 194         {
 195           Start = FT_NEXT_USHORT( p );
 196           End   = FT_NEXT_USHORT( p );
 197           p    += 2;                    /* skip StartCoverageIndex */
 198
 199           result += End - Start + 1;
 200         }
 201       }
 202       break;
 203
 204     default:
 205       ;
 206     }
 207
 208     return result;
 209   }
 210
 211
 212   /*************************************************************************/
 213   /*************************************************************************/
 214   /*****                                                               *****/
 215   /*****                   CLASS DEFINITION TABLE                      *****/
 216   /*****                                                               *****/
 217   /*************************************************************************/
 218   /*************************************************************************/
 219
 220   FT_LOCAL_DEF( void )
 221   otv_ClassDef_validate( FT_Bytes       table,
 222                          OTV_Validator  valid )
 223   {
 224     FT_Bytes  p = table;
 225     FT_UInt   ClassFormat;
 226
 227
 228     OTV_NAME_ENTER( "ClassDef" );
 229
 230     OTV_LIMIT_CHECK( 4 );
 231     ClassFormat = FT_NEXT_USHORT( p );
 232
 233     OTV_TRACE(( " (format %d)\n", ClassFormat ));
 234
 235     switch ( ClassFormat )
 236     {
 237     case 1:     /* ClassDefFormat1 */
 238       {
 239         FT_UInt  StartGlyph;
 240         FT_UInt  GlyphCount;
 241
 242
 243         OTV_LIMIT_CHECK( 4 );
 244
 245         StartGlyph = FT_NEXT_USHORT( p );
 246         GlyphCount = FT_NEXT_USHORT( p );
 247
 248         OTV_TRACE(( " (GlyphCount = %d)\n", GlyphCount ));
 249
 250         OTV_LIMIT_CHECK( GlyphCount * 2 );    /* ClassValueArray */
 251
 252         if ( StartGlyph + GlyphCount - 1 >= valid->glyph_count )
 253           FT_INVALID_GLYPH_ID;
 254       }
 255       break;
 256
 257     case 2:     /* ClassDefFormat2 */
 258       {
 259         FT_UInt  n, ClassRangeCount;
 260         FT_UInt  Start, End, last = 0;
 261
 262
 263         ClassRangeCount = FT_NEXT_USHORT( p );
 264
 265         OTV_TRACE(( " (ClassRangeCount = %d)\n", ClassRangeCount ));
 266
 267         OTV_LIMIT_CHECK( ClassRangeCount * 6 );
 268
 269         /* ClassRangeRecord */
 270         for ( n = 0; n < ClassRangeCount; n++ )
 271         {
 272           Start = FT_NEXT_USHORT( p );
 273           End   = FT_NEXT_USHORT( p );
 274           p    += 2;                        /* skip Class */
 275
 276           if ( Start > End || ( n > 0 && Start <= last ) )
 277             FT_INVALID_DATA;
 278
 279           if ( End >= valid->glyph_count )
 280             FT_INVALID_GLYPH_ID;
 281
 282           last = End;
 283         }
 284       }
 285       break;
 286
 287     default:
 288       FT_INVALID_FORMAT;
 289     }
 290
 291     /* no need to check glyph indices used as input to class definition   */
 292     /* tables since even invalid glyph indices return a meaningful result */
 293
 294     OTV_EXIT;
 295   }
 296
 297
 298   /*************************************************************************/
 299   /*************************************************************************/
 300   /*****                                                               *****/
 301   /*****                      DEVICE TABLE                             *****/
 302   /*****                                                               *****/
 303   /*************************************************************************/
 304   /*************************************************************************/
 305
 306   FT_LOCAL_DEF( void )
 307   otv_Device_validate( FT_Bytes       table,
 308                        OTV_Validator  valid )
 309   {
 310     FT_Bytes  p = table;
 311     FT_UInt   StartSize, EndSize, DeltaFormat, count;
 312
 313
 314     OTV_NAME_ENTER( "Device" );
 315
 316     OTV_LIMIT_CHECK( 8 );
 317     StartSize   = FT_NEXT_USHORT( p );
 318     EndSize     = FT_NEXT_USHORT( p );
 319     DeltaFormat = FT_NEXT_USHORT( p );
 320
 321     if ( DeltaFormat < 1 || DeltaFormat > 3 )
 322       FT_INVALID_FORMAT;
 323
 324     if ( EndSize < StartSize )
 325       FT_INVALID_DATA;
 326
 327     count = EndSize - StartSize + 1;
 328     OTV_LIMIT_CHECK( ( 1 << DeltaFormat ) * count / 8 );  /* DeltaValue */
 329
 330     OTV_EXIT;
 331   }
 332
 333
 334   /*************************************************************************/
 335   /*************************************************************************/
 336   /*****                                                               *****/
 337   /*****                         LOOKUPS                               *****/
 338   /*****                                                               *****/
 339   /*************************************************************************/
 340   /*************************************************************************/
 341
 342   /* uses valid->type_count */
 343   /* uses valid->type_funcs */
 344
 345   FT_LOCAL_DEF( void )
 346   otv_Lookup_validate( FT_Bytes       table,
 347                        OTV_Validator  valid )
 348   {
 349     FT_Bytes           p = table;
 350     FT_UInt            LookupType, SubTableCount;
 351     OTV_Validate_Func  validate;
 352
 353
 354     OTV_NAME_ENTER( "Lookup" );
 355
 356     OTV_LIMIT_CHECK( 6 );
 357     LookupType    = FT_NEXT_USHORT( p );
 358     p            += 2;                      /* skip LookupFlag */
 359     SubTableCount = FT_NEXT_USHORT( p );
 360
 361     OTV_TRACE(( " (type %d)\n", LookupType ));
 362
 363     if ( LookupType == 0 || LookupType > valid->type_count )
 364       FT_INVALID_DATA;
 365
 366     validate = valid->type_funcs[LookupType - 1];
 367
 368     OTV_TRACE(( " (SubTableCount = %d)\n", SubTableCount ));
 369
 370     OTV_LIMIT_CHECK( SubTableCount * 2 );
 371
 372     /* SubTable */
 373     for ( ; SubTableCount > 0; SubTableCount-- )
 374       validate( table + FT_NEXT_USHORT( p ), valid );
 375
 376     OTV_EXIT;
 377   }
 378
 379
 380   /* uses valid->lookup_count */
 381
 382   FT_LOCAL_DEF( void )
 383   otv_LookupList_validate( FT_Bytes       table,
 384                            OTV_Validator  valid )
 385   {
 386     FT_Bytes  p = table;
 387     FT_UInt   LookupCount;
 388
 389
 390     OTV_NAME_ENTER( "LookupList" );
 391
 392     OTV_LIMIT_CHECK( 2 );
 393     LookupCount = FT_NEXT_USHORT( p );
 394
 395     OTV_TRACE(( " (LookupCount = %d)\n", LookupCount ));
 396
 397     OTV_LIMIT_CHECK( LookupCount * 2 );
 398
 399     valid->lookup_count = LookupCount;
 400
 401     /* Lookup */
 402     for ( ; LookupCount > 0; LookupCount-- )
 403       otv_Lookup_validate( table + FT_NEXT_USHORT( p ), valid );
 404
 405     OTV_EXIT;
 406   }
 407
 408
 409   static FT_UInt
 410   otv_LookupList_get_count( FT_Bytes  table )
 411   {
 412     return FT_NEXT_USHORT( table );
 413   }
 414
 415
 416   /*************************************************************************/
 417   /*************************************************************************/
 418   /*****                                                               *****/
 419   /*****                        FEATURES                               *****/
 420   /*****                                                               *****/
 421   /*************************************************************************/
 422   /*************************************************************************/
 423
 424   /* uses valid->lookup_count */
 425
 426   FT_LOCAL_DEF( void )
 427   otv_Feature_validate( FT_Bytes       table,
 428                         OTV_Validator  valid )
 429   {
 430     FT_Bytes  p = table;
 431     FT_UInt   LookupCount;
 432
 433
 434     OTV_NAME_ENTER( "Feature" );
 435
 436     OTV_LIMIT_CHECK( 4 );
 437     p           += 2;                   /* skip FeatureParams (unused) */
 438     LookupCount  = FT_NEXT_USHORT( p );
 439
 440     OTV_TRACE(( " (LookupCount = %d)\n", LookupCount ));
 441
 442     OTV_LIMIT_CHECK( LookupCount * 2 );
 443
 444     /* LookupListIndex */
 445     for ( ; LookupCount > 0; LookupCount-- )
 446       if ( FT_NEXT_USHORT( p ) >= valid->lookup_count )
 447         FT_INVALID_DATA;
 448
 449     OTV_EXIT;
 450   }
 451
 452
 453   static FT_UInt
 454   otv_Feature_get_count( FT_Bytes  table )
 455   {
 456     return FT_NEXT_USHORT( table );
 457   }
 458
 459
 460   /* sets valid->lookup_count */
 461
 462   FT_LOCAL_DEF( void )
 463   otv_FeatureList_validate( FT_Bytes       table,
 464                             FT_Bytes       lookups,
 465                             OTV_Validator  valid )
 466   {
 467     FT_Bytes  p = table;
 468     FT_UInt   FeatureCount;
 469
 470
 471     OTV_NAME_ENTER( "FeatureList" );
 472
 473     OTV_LIMIT_CHECK( 2 );
 474     FeatureCount = FT_NEXT_USHORT( p );
 475
 476     OTV_TRACE(( " (FeatureCount = %d)\n", FeatureCount ));
 477
 478     OTV_LIMIT_CHECK( FeatureCount * 2 );
 479
 480     valid->lookup_count = otv_LookupList_get_count( lookups );
 481
 482     /* FeatureRecord */
 483     for ( ; FeatureCount > 0; FeatureCount-- )
 484     {
 485       p += 4;       /* skip FeatureTag */
 486
 487       /* Feature */
 488       otv_Feature_validate( table + FT_NEXT_USHORT( p ), valid );
 489     }
 490
 491     OTV_EXIT;
 492   }
 493
 494
 495   /*************************************************************************/
 496   /*************************************************************************/
 497   /*****                                                               *****/
 498   /*****                       LANGUAGE SYSTEM                         *****/
 499   /*****                                                               *****/
 500   /*************************************************************************/
 501   /*************************************************************************/
 502
 503
 504   /* uses valid->extra1 (number of features) */
 505
 506   FT_LOCAL_DEF( void )
 507   otv_LangSys_validate( FT_Bytes       table,
 508                         OTV_Validator  valid )
 509   {
 510     FT_Bytes  p = table;
 511     FT_UInt   ReqFeatureIndex;
 512     FT_UInt   FeatureCount;
 513
 514
 515     OTV_NAME_ENTER( "LangSys" );
 516
 517     OTV_LIMIT_CHECK( 6 );
 518     p              += 2;                    /* skip LookupOrder (unused) */
 519     ReqFeatureIndex = FT_NEXT_USHORT( p );
 520     FeatureCount    = FT_NEXT_USHORT( p );
 521
 522     OTV_TRACE(( " (ReqFeatureIndex = %d)\n", ReqFeatureIndex ));
 523     OTV_TRACE(( " (FeatureCount = %d)\n",    FeatureCount    ));
 524
 525     if ( ReqFeatureIndex != 0xFFFFU && ReqFeatureIndex >= valid->extra1 )
 526       FT_INVALID_DATA;
 527
 528     OTV_LIMIT_CHECK( FeatureCount * 2 );
 529
 530     /* FeatureIndex */
 531     for ( ; FeatureCount > 0; FeatureCount-- )
 532       if ( FT_NEXT_USHORT( p ) >= valid->extra1 )
 533         FT_INVALID_DATA;
 534
 535     OTV_EXIT;
 536   }
 537
 538
 539   /*************************************************************************/
 540   /*************************************************************************/
 541   /*****                                                               *****/
 542   /*****                           SCRIPTS                             *****/
 543   /*****                                                               *****/
 544   /*************************************************************************/
 545   /*************************************************************************/
 546
 547   FT_LOCAL_DEF( void )
 548   otv_Script_validate( FT_Bytes       table,
 549                        OTV_Validator  valid )
 550   {
 551     FT_UInt   DefaultLangSys, LangSysCount;
 552     FT_Bytes  p = table;
 553
 554
 555     OTV_NAME_ENTER( "Script" );
 556
 557     OTV_LIMIT_CHECK( 4 );
 558     DefaultLangSys = FT_NEXT_USHORT( p );
 559     LangSysCount   = FT_NEXT_USHORT( p );
 560
 561     OTV_TRACE(( " (LangSysCount = %d)\n", LangSysCount ));
 562
 563     if ( DefaultLangSys != 0 )
 564       otv_LangSys_validate( table + DefaultLangSys, valid );
 565
 566     OTV_LIMIT_CHECK( LangSysCount * 6 );
 567
 568     /* LangSysRecord */
 569     for ( ; LangSysCount > 0; LangSysCount-- )
 570     {
 571       p += 4;       /* skip LangSysTag */
 572
 573       /* LangSys */
 574       otv_LangSys_validate( table + FT_NEXT_USHORT( p ), valid );
 575     }
 576
 577     OTV_EXIT;
 578   }
 579
 580
 581   /* sets valid->extra1 (number of features) */
 582
 583   FT_LOCAL_DEF( void )
 584   otv_ScriptList_validate( FT_Bytes       table,
 585                            FT_Bytes       features,
 586                            OTV_Validator  valid )
 587   {
 588     FT_UInt   ScriptCount;
 589     FT_Bytes  p = table;
 590
 591
 592     OTV_NAME_ENTER( "ScriptList" );
 593
 594     OTV_LIMIT_CHECK( 2 );
 595     ScriptCount = FT_NEXT_USHORT( p );
 596
 597     OTV_TRACE(( " (ScriptCount = %d)\n", ScriptCount ));
 598
 599     OTV_LIMIT_CHECK( ScriptCount * 6 );
 600
 601     valid->extra1 = otv_Feature_get_count( features );
 602
 603     /* ScriptRecord */
 604     for ( ; ScriptCount > 0; ScriptCount-- )
 605     {
 606       p += 4;       /* skip ScriptTag */
 607
 608       otv_Script_validate( table + FT_NEXT_USHORT( p ), valid ); /* Script */
 609     }
 610
 611     OTV_EXIT;
 612   }
 613
 614
 615   /*************************************************************************/
 616   /*************************************************************************/
 617   /*****                                                               *****/
 618   /*****                      UTILITY FUNCTIONS                        *****/
 619   /*****                                                               *****/
 620   /*************************************************************************/
 621   /*************************************************************************/
 622
 623   /*
 624      u:   uint16
 625      ux:  unit16 [x]
 626
 627      s:   struct
 628      sx:  struct [x]
 629      sxy: struct [x], using external y count
 630
 631      x:   uint16 x
 632
 633      C:   Coverage
 634
 635      O:   Offset
 636      On:  Offset (NULL)
 637      Ox:  Offset [x]
 638      Onx: Offset (NULL) [x]
 639   */
 640
 641   FT_LOCAL_DEF( void )
 642   otv_x_Ox( FT_Bytes       table,
 643             OTV_Validator  valid )
 644   {
 645     FT_Bytes           p = table;
 646     FT_UInt            Count;
 647     OTV_Validate_Func  func;
 648
 649
 650     OTV_ENTER;
 651
 652     OTV_LIMIT_CHECK( 2 );
 653     Count = FT_NEXT_USHORT( p );
 654
 655     OTV_TRACE(( " (Count = %d)\n", Count ));
 656
 657     OTV_LIMIT_CHECK( Count * 2 );
 658
 659     valid->nesting_level++;
 660     func = valid->func[valid->nesting_level];
 661
 662     for ( ; Count > 0; Count-- )
 663       func( table + FT_NEXT_USHORT( p ), valid );
 664
 665     valid->nesting_level--;
 666
 667     OTV_EXIT;
 668   }
 669
 670
 671   FT_LOCAL_DEF( void )
 672   otv_u_C_x_Ox( FT_Bytes       table,
 673                 OTV_Validator  valid )
 674   {
 675     FT_Bytes           p = table;
 676     FT_UInt            Count, Coverage;
 677     OTV_Validate_Func  func;
 678
 679
 680     OTV_ENTER;
 681
 682     p += 2;     /* skip Format */
 683
 684     OTV_LIMIT_CHECK( 4 );
 685     Coverage = FT_NEXT_USHORT( p );
 686     Count    = FT_NEXT_USHORT( p );
 687
 688     OTV_TRACE(( " (Count = %d)\n", Count ));
 689
 690     otv_Coverage_validate( table + Coverage, valid, Count );
 691
 692     OTV_LIMIT_CHECK( Count * 2 );
 693
 694     valid->nesting_level++;
 695     func = valid->func[valid->nesting_level];
 696
 697     for ( ; Count > 0; Count-- )
 698       func( table + FT_NEXT_USHORT( p ), valid );
 699
 700     valid->nesting_level--;
 701
 702     OTV_EXIT;
 703   }
 704
 705
 706   /* uses valid->extra1 (if > 0: array value limit) */
 707
 708   FT_LOCAL_DEF( void )
 709   otv_x_ux( FT_Bytes       table,
 710             OTV_Validator  valid )
 711   {
 712     FT_Bytes  p = table;
 713     FT_UInt   Count;
 714
 715
 716     OTV_ENTER;
 717
 718     OTV_LIMIT_CHECK( 2 );
 719     Count = FT_NEXT_USHORT( p );
 720
 721     OTV_TRACE(( " (Count = %d)\n", Count ));
 722
 723     OTV_LIMIT_CHECK( Count * 2 );
 724
 725     if ( valid->extra1 )
 726     {
 727       for ( ; Count > 0; Count-- )
 728         if ( FT_NEXT_USHORT( p ) >= valid->extra1 )
 729           FT_INVALID_DATA;
 730     }
 731
 732     OTV_EXIT;
 733   }
 734
 735
 736   /* `ux' in the function's name is not really correct since only x-1 */
 737   /* elements are tested                                              */
 738
 739   /* uses valid->extra1 (array value limit) */
 740
 741   FT_LOCAL_DEF( void )
 742   otv_x_y_ux_sy( FT_Bytes       table,
 743                  OTV_Validator  valid )
 744   {
 745     FT_Bytes  p = table;
 746     FT_UInt   Count1, Count2;
 747
 748
 749     OTV_ENTER;
 750
 751     OTV_LIMIT_CHECK( 4 );
 752     Count1 = FT_NEXT_USHORT( p );
 753     Count2 = FT_NEXT_USHORT( p );
 754
 755     OTV_TRACE(( " (Count1 = %d)\n", Count1 ));
 756     OTV_TRACE(( " (Count2 = %d)\n", Count2 ));
 757
 758     if ( Count1 == 0 )
 759       FT_INVALID_DATA;
 760
 761     OTV_LIMIT_CHECK( ( Count1 - 1 ) * 2 + Count2 * 4 );
 762     p += ( Count1 - 1 ) * 2;
 763
 764     for ( ; Count2 > 0; Count2-- )
 765     {
 766       if ( FT_NEXT_USHORT( p ) >= Count1 )
 767         FT_INVALID_DATA;
 768
 769       if ( FT_NEXT_USHORT( p ) >= valid->extra1 )
 770         FT_INVALID_DATA;
 771     }
 772
 773     OTV_EXIT;
 774   }
 775
 776
 777   /* `uy' in the function's name is not really correct since only y-1 */
 778   /* elements are tested                                              */
 779
 780   /* uses valid->extra1 (array value limit) */
 781
 782   FT_LOCAL_DEF( void )
 783   otv_x_ux_y_uy_z_uz_p_sp( FT_Bytes       table,
 784                            OTV_Validator  valid )
 785   {
 786     FT_Bytes  p = table;
 787     FT_UInt   BacktrackCount, InputCount, LookaheadCount;
 788     FT_UInt   Count;
 789
 790
 791     OTV_ENTER;
 792
 793     OTV_LIMIT_CHECK( 2 );
 794     BacktrackCount = FT_NEXT_USHORT( p );
 795
 796     OTV_TRACE(( " (BacktrackCount = %d)\n", BacktrackCount ));
 797
 798     OTV_LIMIT_CHECK( BacktrackCount * 2 + 2 );
 799     p += BacktrackCount * 2;
 800
 801     InputCount = FT_NEXT_USHORT( p );
 802     if ( InputCount == 0 )
 803       FT_INVALID_DATA;
 804
 805     OTV_TRACE(( " (InputCount = %d)\n", InputCount ));
 806
 807     OTV_LIMIT_CHECK( InputCount * 2 );
 808     p += ( InputCount - 1 ) * 2;
 809
 810     LookaheadCount = FT_NEXT_USHORT( p );
 811
 812     OTV_TRACE(( " (LookaheadCount = %d)\n", LookaheadCount ));
 813
 814     OTV_LIMIT_CHECK( LookaheadCount * 2 + 2 );
 815     p += LookaheadCount * 2;
 816
 817     Count = FT_NEXT_USHORT( p );
 818
 819     OTV_TRACE(( " (Count = %d)\n", Count ));
 820
 821     OTV_LIMIT_CHECK( Count * 4 );
 822
 823     for ( ; Count > 0; Count-- )
 824     {
 825       if ( FT_NEXT_USHORT( p ) >= InputCount )
 826         FT_INVALID_DATA;
 827
 828       if ( FT_NEXT_USHORT( p ) >= valid->extra1 )
 829         FT_INVALID_DATA;
 830     }
 831
 832     OTV_EXIT;
 833   }
 834
 835
 836   /* sets valid->extra1 (valid->lookup_count) */
 837
 838   FT_LOCAL_DEF( void )
 839   otv_u_O_O_x_Onx( FT_Bytes       table,
 840                    OTV_Validator  valid )
 841   {
 842     FT_Bytes           p = table;
 843     FT_UInt            Coverage, ClassDef, ClassSetCount;
 844     OTV_Validate_Func  func;
 845
 846
 847     OTV_ENTER;
 848
 849     p += 2;     /* skip Format */
 850
 851     OTV_LIMIT_CHECK( 6 );
 852     Coverage      = FT_NEXT_USHORT( p );
 853     ClassDef      = FT_NEXT_USHORT( p );
 854     ClassSetCount = FT_NEXT_USHORT( p );
 855
 856     OTV_TRACE(( " (ClassSetCount = %d)\n", ClassSetCount ));
 857
 858     otv_Coverage_validate( table + Coverage, valid, -1 );
 859     otv_ClassDef_validate( table + ClassDef, valid );
 860
 861     OTV_LIMIT_CHECK( ClassSetCount * 2 );
 862
 863     valid->nesting_level++;
 864     func          = valid->func[valid->nesting_level];
 865     valid->extra1 = valid->lookup_count;
 866
 867     for ( ; ClassSetCount > 0; ClassSetCount-- )
 868     {
 869       FT_UInt  offset = FT_NEXT_USHORT( p );
 870
 871
 872       if ( offset )
 873         func( table + offset, valid );
 874     }
 875
 876     valid->nesting_level--;
 877
 878     OTV_EXIT;
 879   }
 880
 881
 882   /* uses valid->lookup_count */
 883
 884   FT_LOCAL_DEF( void )
 885   otv_u_x_y_Ox_sy( FT_Bytes       table,
 886                    OTV_Validator  valid )
 887   {
 888     FT_Bytes  p = table;
 889     FT_UInt   GlyphCount, Count, count1;
 890
 891
 892     OTV_ENTER;
 893
 894     p += 2;     /* skip Format */
 895
 896     OTV_LIMIT_CHECK( 4 );
 897     GlyphCount = FT_NEXT_USHORT( p );
 898     Count      = FT_NEXT_USHORT( p );
 899
 900     OTV_TRACE(( " (GlyphCount = %d)\n", GlyphCount ));
 901     OTV_TRACE(( " (Count = %d)\n",      Count      ));
 902
 903     OTV_LIMIT_CHECK( GlyphCount * 2 + Count * 4 );
 904
 905     for ( count1 = GlyphCount; count1 > 0; count1-- )
 906       otv_Coverage_validate( table + FT_NEXT_USHORT( p ), valid, -1 );
 907
 908     for ( ; Count > 0; Count-- )
 909     {
 910       if ( FT_NEXT_USHORT( p ) >= GlyphCount )
 911         FT_INVALID_DATA;
 912
 913       if ( FT_NEXT_USHORT( p ) >= valid->lookup_count )
 914         FT_INVALID_DATA;
 915     }
 916
 917     OTV_EXIT;
 918   }
 919
 920
 921   /* sets valid->extra1 (valid->lookup_count)    */
 922
 923   FT_LOCAL_DEF( void )
 924   otv_u_O_O_O_O_x_Onx( FT_Bytes       table,
 925                        OTV_Validator  valid )
 926   {
 927     FT_Bytes           p = table;
 928     FT_UInt            Coverage;
 929     FT_UInt            BacktrackClassDef, InputClassDef, LookaheadClassDef;
 930     FT_UInt            ChainClassSetCount;
 931     OTV_Validate_Func  func;
 932
 933
 934     OTV_ENTER;
 935
 936     p += 2;     /* skip Format */
 937
 938     OTV_LIMIT_CHECK( 10 );
 939     Coverage           = FT_NEXT_USHORT( p );
 940     BacktrackClassDef  = FT_NEXT_USHORT( p );
 941     InputClassDef      = FT_NEXT_USHORT( p );
 942     LookaheadClassDef  = FT_NEXT_USHORT( p );
 943     ChainClassSetCount = FT_NEXT_USHORT( p );
 944
 945     OTV_TRACE(( " (ChainClassSetCount = %d)\n", ChainClassSetCount ));
 946
 947     otv_Coverage_validate( table + Coverage, valid, -1 );
 948
 949     otv_ClassDef_validate( table + BacktrackClassDef,  valid );
 950     otv_ClassDef_validate( table + InputClassDef, valid );
 951     otv_ClassDef_validate( table + LookaheadClassDef, valid );
 952
 953     OTV_LIMIT_CHECK( ChainClassSetCount * 2 );
 954
 955     valid->nesting_level++;
 956     func          = valid->func[valid->nesting_level];
 957     valid->extra1 = valid->lookup_count;
 958
 959     for ( ; ChainClassSetCount > 0; ChainClassSetCount-- )
 960     {
 961       FT_UInt  offset = FT_NEXT_USHORT( p );
 962
 963
 964       if ( offset )
 965         func( table + offset, valid );
 966     }
 967
 968     valid->nesting_level--;
 969
 970     OTV_EXIT;
 971   }
 972
 973
 974   /* uses valid->lookup_count */
 975
 976   FT_LOCAL_DEF( void )
 977   otv_u_x_Ox_y_Oy_z_Oz_p_sp( FT_Bytes       table,
 978                              OTV_Validator  valid )
 979   {
 980     FT_Bytes  p = table;
 981     FT_UInt   BacktrackGlyphCount, InputGlyphCount, LookaheadGlyphCount;
 982     FT_UInt   count1, count2;
 983
 984
 985     OTV_ENTER;
 986
 987     p += 2;     /* skip Format */
 988
 989     OTV_LIMIT_CHECK( 2 );
 990     BacktrackGlyphCount = FT_NEXT_USHORT( p );
 991
 992     OTV_TRACE(( " (BacktrackGlyphCount = %d)\n", BacktrackGlyphCount ));
 993
 994     OTV_LIMIT_CHECK( BacktrackGlyphCount * 2 + 2 );
 995
 996     for ( ; BacktrackGlyphCount > 0; BacktrackGlyphCount-- )
 997       otv_Coverage_validate( table + FT_NEXT_USHORT( p ), valid, -1 );
 998
 999     InputGlyphCount = FT_NEXT_USHORT( p );
1000
1001     OTV_TRACE(( " (InputGlyphCount = %d)\n", InputGlyphCount ));
1002
1003     OTV_LIMIT_CHECK( InputGlyphCount * 2 + 2 );
1004
1005     for ( count1 = InputGlyphCount; count1 > 0; count1-- )
1006       otv_Coverage_validate( table + FT_NEXT_USHORT( p ), valid, -1 );
1007
1008     LookaheadGlyphCount = FT_NEXT_USHORT( p );
1009
1010     OTV_TRACE(( " (LookaheadGlyphCount = %d)\n", LookaheadGlyphCount ));
1011
1012     OTV_LIMIT_CHECK( LookaheadGlyphCount * 2 + 2 );
1013
1014     for ( ; LookaheadGlyphCount > 0; LookaheadGlyphCount-- )
1015       otv_Coverage_validate( table + FT_NEXT_USHORT( p ), valid, -1 );
1016
1017     count2 = FT_NEXT_USHORT( p );
1018
1019     OTV_TRACE(( " (Count = %d)\n", count2 ));
1020
1021     OTV_LIMIT_CHECK( count2 * 4 );
1022
1023     for ( ; count2 > 0; count2-- )
1024     {
1025       if ( FT_NEXT_USHORT( p ) >= InputGlyphCount )
1026         FT_INVALID_DATA;
1027
1028       if ( FT_NEXT_USHORT( p ) >= valid->lookup_count )
1029         FT_INVALID_DATA;
1030     }
1031
1032     OTV_EXIT;
1033   }
1034
1035
1036   FT_LOCAL_DEF( FT_UInt )
1037   otv_GSUBGPOS_get_Lookup_count( FT_Bytes  table )
1038   {
1039     FT_Bytes  p = table + 8;
1040
1041
1042     return otv_LookupList_get_count( table + FT_NEXT_USHORT( p ) );
1043   }
1044
1045
1046   FT_LOCAL_DEF( FT_UInt )
1047   otv_GSUBGPOS_have_MarkAttachmentType_flag( FT_Bytes  table )
1048   {
1049     FT_Bytes  p, lookup;
1050     FT_UInt   count;
1051
1052
1053     if ( !table )
1054       return 0;
1055
1056     /* LookupList */
1057     p      = table + 8;
1058     table += FT_NEXT_USHORT( p );
1059
1060     /* LookupCount */
1061     p     = table;
1062     count = FT_NEXT_USHORT( p );
1063
1064     for ( ; count > 0; count-- )
1065     {
1066       FT_Bytes  oldp;
1067
1068
1069       /* Lookup */
1070       lookup = table + FT_NEXT_USHORT( p );
1071
1072       oldp = p;
1073
1074       /* LookupFlag */
1075       p = lookup + 2;
1076       if ( FT_NEXT_USHORT( p ) & 0xFF00U )
1077         return 1;
1078
1079       p = oldp;
1080     }
1081
1082     return 0;
1083   }
1084
1085
1086 /* END */