ref: d20dc3928b9d3ee075106b7684dab6111d6a5899
dir: /src/otvalid/otvcommn.c/
/**************************************************************************** * * otvcommn.c * * OpenType common tables validation (body). * * Copyright 2004-2018 by * David Turner, Robert Wilhelm, and Werner Lemberg. * * This file is part of the FreeType project, and may only be used, * modified, and distributed under the terms of the FreeType project * license, LICENSE.TXT. By continuing to use, modify, or distribute * this file you indicate that you have read the license and * understand and accept it fully. * */ #include "otvcommn.h" /************************************************************************** * * The macro FT_COMPONENT is used in trace mode. It is an implicit * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log * messages during execution. */ #undef FT_COMPONENT #define FT_COMPONENT otvcommon /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** COVERAGE TABLE *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ FT_LOCAL_DEF( void ) otv_Coverage_validate( FT_Bytes table, OTV_Validator otvalid, FT_Int expected_count ) { FT_Bytes p = table; FT_UInt CoverageFormat; FT_UInt total = 0; OTV_NAME_ENTER( "Coverage" ); OTV_LIMIT_CHECK( 4 ); CoverageFormat = FT_NEXT_USHORT( p ); OTV_TRACE(( " (format %d)\n", CoverageFormat )); switch ( CoverageFormat ) { case 1: /* CoverageFormat1 */ { FT_UInt GlyphCount; FT_UInt i; GlyphCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (GlyphCount = %d)\n", GlyphCount )); OTV_LIMIT_CHECK( GlyphCount * 2 ); /* GlyphArray */ for ( i = 0; i < GlyphCount; i++ ) { FT_UInt gid; gid = FT_NEXT_USHORT( p ); if ( gid >= otvalid->glyph_count ) FT_INVALID_GLYPH_ID; } total = GlyphCount; } break; case 2: /* CoverageFormat2 */ { FT_UInt n, RangeCount; FT_UInt Start, End, StartCoverageIndex, last = 0; RangeCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (RangeCount = %d)\n", RangeCount )); OTV_LIMIT_CHECK( RangeCount * 6 ); /* RangeRecord */ for ( n = 0; n < RangeCount; n++ ) { Start = FT_NEXT_USHORT( p ); End = FT_NEXT_USHORT( p ); StartCoverageIndex = FT_NEXT_USHORT( p ); if ( Start > End || StartCoverageIndex != total ) FT_INVALID_DATA; if ( End >= otvalid->glyph_count ) FT_INVALID_GLYPH_ID; if ( n > 0 && Start <= last ) FT_INVALID_DATA; total += End - Start + 1; last = End; } } break; default: FT_INVALID_FORMAT; } /* Generally, a coverage table offset has an associated count field. */ /* The number of glyphs in the table should match this field. If */ /* there is no associated count, a value of -1 tells us not to check. */ if ( expected_count != -1 && (FT_UInt)expected_count != total ) FT_INVALID_DATA; OTV_EXIT; } FT_LOCAL_DEF( FT_UInt ) otv_Coverage_get_first( FT_Bytes table ) { FT_Bytes p = table; p += 4; /* skip CoverageFormat and Glyph/RangeCount */ return FT_NEXT_USHORT( p ); } FT_LOCAL_DEF( FT_UInt ) otv_Coverage_get_last( FT_Bytes table ) { FT_Bytes p = table; FT_UInt CoverageFormat = FT_NEXT_USHORT( p ); FT_UInt count = FT_NEXT_USHORT( p ); /* Glyph/RangeCount */ FT_UInt result = 0; switch ( CoverageFormat ) { case 1: p += ( count - 1 ) * 2; result = FT_NEXT_USHORT( p ); break; case 2: p += ( count - 1 ) * 6 + 2; result = FT_NEXT_USHORT( p ); break; default: ; } return result; } FT_LOCAL_DEF( FT_UInt ) otv_Coverage_get_count( FT_Bytes table ) { FT_Bytes p = table; FT_UInt CoverageFormat = FT_NEXT_USHORT( p ); FT_UInt count = FT_NEXT_USHORT( p ); /* Glyph/RangeCount */ FT_UInt result = 0; switch ( CoverageFormat ) { case 1: return count; case 2: { FT_UInt Start, End; for ( ; count > 0; count-- ) { Start = FT_NEXT_USHORT( p ); End = FT_NEXT_USHORT( p ); p += 2; /* skip StartCoverageIndex */ result += End - Start + 1; } } break; default: ; } return result; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** CLASS DEFINITION TABLE *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ FT_LOCAL_DEF( void ) otv_ClassDef_validate( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt ClassFormat; OTV_NAME_ENTER( "ClassDef" ); OTV_LIMIT_CHECK( 4 ); ClassFormat = FT_NEXT_USHORT( p ); OTV_TRACE(( " (format %d)\n", ClassFormat )); switch ( ClassFormat ) { case 1: /* ClassDefFormat1 */ { FT_UInt StartGlyph; FT_UInt GlyphCount; OTV_LIMIT_CHECK( 4 ); StartGlyph = FT_NEXT_USHORT( p ); GlyphCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (GlyphCount = %d)\n", GlyphCount )); OTV_LIMIT_CHECK( GlyphCount * 2 ); /* ClassValueArray */ if ( StartGlyph + GlyphCount - 1 >= otvalid->glyph_count ) FT_INVALID_GLYPH_ID; } break; case 2: /* ClassDefFormat2 */ { FT_UInt n, ClassRangeCount; FT_UInt Start, End, last = 0; ClassRangeCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (ClassRangeCount = %d)\n", ClassRangeCount )); OTV_LIMIT_CHECK( ClassRangeCount * 6 ); /* ClassRangeRecord */ for ( n = 0; n < ClassRangeCount; n++ ) { Start = FT_NEXT_USHORT( p ); End = FT_NEXT_USHORT( p ); p += 2; /* skip Class */ if ( Start > End || ( n > 0 && Start <= last ) ) FT_INVALID_DATA; if ( End >= otvalid->glyph_count ) FT_INVALID_GLYPH_ID; last = End; } } break; default: FT_INVALID_FORMAT; } /* no need to check glyph indices used as input to class definition */ /* tables since even invalid glyph indices return a meaningful result */ OTV_EXIT; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** DEVICE TABLE *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ FT_LOCAL_DEF( void ) otv_Device_validate( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt StartSize, EndSize, DeltaFormat, count; OTV_NAME_ENTER( "Device" ); OTV_LIMIT_CHECK( 6 ); StartSize = FT_NEXT_USHORT( p ); EndSize = FT_NEXT_USHORT( p ); DeltaFormat = FT_NEXT_USHORT( p ); if ( DeltaFormat == 0x8000U ) { /* VariationIndex, nothing to do */ } else { if ( DeltaFormat < 1 || DeltaFormat > 3 ) FT_INVALID_FORMAT; if ( EndSize < StartSize ) FT_INVALID_DATA; count = EndSize - StartSize + 1; OTV_LIMIT_CHECK( ( 1 << DeltaFormat ) * count / 8 ); /* DeltaValue */ } OTV_EXIT; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** LOOKUPS *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ /* uses otvalid->type_count */ /* uses otvalid->type_funcs */ FT_LOCAL_DEF( void ) otv_Lookup_validate( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt LookupType, LookupFlag, SubTableCount; OTV_Validate_Func validate; OTV_NAME_ENTER( "Lookup" ); OTV_LIMIT_CHECK( 6 ); LookupType = FT_NEXT_USHORT( p ); LookupFlag = FT_NEXT_USHORT( p ); SubTableCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (type %d)\n", LookupType )); if ( LookupType == 0 || LookupType > otvalid->type_count ) FT_INVALID_DATA; validate = otvalid->type_funcs[LookupType - 1]; OTV_TRACE(( " (SubTableCount = %d)\n", SubTableCount )); OTV_LIMIT_CHECK( SubTableCount * 2 ); /* SubTable */ for ( ; SubTableCount > 0; SubTableCount-- ) validate( table + FT_NEXT_USHORT( p ), otvalid ); if ( LookupFlag & 0x10 ) OTV_LIMIT_CHECK( 2 ); /* MarkFilteringSet */ OTV_EXIT; } /* uses valid->lookup_count */ FT_LOCAL_DEF( void ) otv_LookupList_validate( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt LookupCount; OTV_NAME_ENTER( "LookupList" ); OTV_LIMIT_CHECK( 2 ); LookupCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (LookupCount = %d)\n", LookupCount )); OTV_LIMIT_CHECK( LookupCount * 2 ); otvalid->lookup_count = LookupCount; /* Lookup */ for ( ; LookupCount > 0; LookupCount-- ) otv_Lookup_validate( table + FT_NEXT_USHORT( p ), otvalid ); OTV_EXIT; } static FT_UInt otv_LookupList_get_count( FT_Bytes table ) { return FT_NEXT_USHORT( table ); } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** FEATURES *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ /* uses otvalid->lookup_count */ FT_LOCAL_DEF( void ) otv_Feature_validate( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt LookupCount; OTV_NAME_ENTER( "Feature" ); OTV_LIMIT_CHECK( 4 ); p += 2; /* skip FeatureParams (unused) */ LookupCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (LookupCount = %d)\n", LookupCount )); OTV_LIMIT_CHECK( LookupCount * 2 ); /* LookupListIndex */ for ( ; LookupCount > 0; LookupCount-- ) if ( FT_NEXT_USHORT( p ) >= otvalid->lookup_count ) FT_INVALID_DATA; OTV_EXIT; } static FT_UInt otv_Feature_get_count( FT_Bytes table ) { return FT_NEXT_USHORT( table ); } /* sets otvalid->lookup_count */ FT_LOCAL_DEF( void ) otv_FeatureList_validate( FT_Bytes table, FT_Bytes lookups, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt FeatureCount; OTV_NAME_ENTER( "FeatureList" ); OTV_LIMIT_CHECK( 2 ); FeatureCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (FeatureCount = %d)\n", FeatureCount )); OTV_LIMIT_CHECK( FeatureCount * 2 ); otvalid->lookup_count = otv_LookupList_get_count( lookups ); /* FeatureRecord */ for ( ; FeatureCount > 0; FeatureCount-- ) { p += 4; /* skip FeatureTag */ /* Feature */ otv_Feature_validate( table + FT_NEXT_USHORT( p ), otvalid ); } OTV_EXIT; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** LANGUAGE SYSTEM *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ /* uses otvalid->extra1 (number of features) */ FT_LOCAL_DEF( void ) otv_LangSys_validate( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt ReqFeatureIndex; FT_UInt FeatureCount; OTV_NAME_ENTER( "LangSys" ); OTV_LIMIT_CHECK( 6 ); p += 2; /* skip LookupOrder (unused) */ ReqFeatureIndex = FT_NEXT_USHORT( p ); FeatureCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (ReqFeatureIndex = %d)\n", ReqFeatureIndex )); OTV_TRACE(( " (FeatureCount = %d)\n", FeatureCount )); if ( ReqFeatureIndex != 0xFFFFU && ReqFeatureIndex >= otvalid->extra1 ) FT_INVALID_DATA; OTV_LIMIT_CHECK( FeatureCount * 2 ); /* FeatureIndex */ for ( ; FeatureCount > 0; FeatureCount-- ) if ( FT_NEXT_USHORT( p ) >= otvalid->extra1 ) FT_INVALID_DATA; OTV_EXIT; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** SCRIPTS *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ FT_LOCAL_DEF( void ) otv_Script_validate( FT_Bytes table, OTV_Validator otvalid ) { FT_UInt DefaultLangSys, LangSysCount; FT_Bytes p = table; OTV_NAME_ENTER( "Script" ); OTV_LIMIT_CHECK( 4 ); DefaultLangSys = FT_NEXT_USHORT( p ); LangSysCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (LangSysCount = %d)\n", LangSysCount )); if ( DefaultLangSys != 0 ) otv_LangSys_validate( table + DefaultLangSys, otvalid ); OTV_LIMIT_CHECK( LangSysCount * 6 ); /* LangSysRecord */ for ( ; LangSysCount > 0; LangSysCount-- ) { p += 4; /* skip LangSysTag */ /* LangSys */ otv_LangSys_validate( table + FT_NEXT_USHORT( p ), otvalid ); } OTV_EXIT; } /* sets otvalid->extra1 (number of features) */ FT_LOCAL_DEF( void ) otv_ScriptList_validate( FT_Bytes table, FT_Bytes features, OTV_Validator otvalid ) { FT_UInt ScriptCount; FT_Bytes p = table; OTV_NAME_ENTER( "ScriptList" ); OTV_LIMIT_CHECK( 2 ); ScriptCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (ScriptCount = %d)\n", ScriptCount )); OTV_LIMIT_CHECK( ScriptCount * 6 ); otvalid->extra1 = otv_Feature_get_count( features ); /* ScriptRecord */ for ( ; ScriptCount > 0; ScriptCount-- ) { p += 4; /* skip ScriptTag */ otv_Script_validate( table + FT_NEXT_USHORT( p ), otvalid ); /* Script */ } OTV_EXIT; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** UTILITY FUNCTIONS *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ /* u: uint16 ux: unit16 [x] s: struct sx: struct [x] sxy: struct [x], using external y count x: uint16 x C: Coverage O: Offset On: Offset (NULL) Ox: Offset [x] Onx: Offset (NULL) [x] */ FT_LOCAL_DEF( void ) otv_x_Ox( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt Count; OTV_Validate_Func func; OTV_ENTER; OTV_LIMIT_CHECK( 2 ); Count = FT_NEXT_USHORT( p ); OTV_TRACE(( " (Count = %d)\n", Count )); OTV_LIMIT_CHECK( Count * 2 ); otvalid->nesting_level++; func = otvalid->func[otvalid->nesting_level]; for ( ; Count > 0; Count-- ) func( table + FT_NEXT_USHORT( p ), otvalid ); otvalid->nesting_level--; OTV_EXIT; } FT_LOCAL_DEF( void ) otv_u_C_x_Ox( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt Count, Coverage; OTV_Validate_Func func; OTV_ENTER; p += 2; /* skip Format */ OTV_LIMIT_CHECK( 4 ); Coverage = FT_NEXT_USHORT( p ); Count = FT_NEXT_USHORT( p ); OTV_TRACE(( " (Count = %d)\n", Count )); otv_Coverage_validate( table + Coverage, otvalid, (FT_Int)Count ); OTV_LIMIT_CHECK( Count * 2 ); otvalid->nesting_level++; func = otvalid->func[otvalid->nesting_level]; for ( ; Count > 0; Count-- ) func( table + FT_NEXT_USHORT( p ), otvalid ); otvalid->nesting_level--; OTV_EXIT; } /* uses otvalid->extra1 (if > 0: array value limit) */ FT_LOCAL_DEF( void ) otv_x_ux( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt Count; OTV_ENTER; OTV_LIMIT_CHECK( 2 ); Count = FT_NEXT_USHORT( p ); OTV_TRACE(( " (Count = %d)\n", Count )); OTV_LIMIT_CHECK( Count * 2 ); if ( otvalid->extra1 ) { for ( ; Count > 0; Count-- ) if ( FT_NEXT_USHORT( p ) >= otvalid->extra1 ) FT_INVALID_DATA; } OTV_EXIT; } /* `ux' in the function's name is not really correct since only x-1 */ /* elements are tested */ /* uses otvalid->extra1 (array value limit) */ FT_LOCAL_DEF( void ) otv_x_y_ux_sy( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt Count1, Count2; OTV_ENTER; OTV_LIMIT_CHECK( 4 ); Count1 = FT_NEXT_USHORT( p ); Count2 = FT_NEXT_USHORT( p ); OTV_TRACE(( " (Count1 = %d)\n", Count1 )); OTV_TRACE(( " (Count2 = %d)\n", Count2 )); if ( Count1 == 0 ) FT_INVALID_DATA; OTV_LIMIT_CHECK( ( Count1 - 1 ) * 2 + Count2 * 4 ); p += ( Count1 - 1 ) * 2; for ( ; Count2 > 0; Count2-- ) { if ( FT_NEXT_USHORT( p ) >= Count1 ) FT_INVALID_DATA; if ( FT_NEXT_USHORT( p ) >= otvalid->extra1 ) FT_INVALID_DATA; } OTV_EXIT; } /* `uy' in the function's name is not really correct since only y-1 */ /* elements are tested */ /* uses otvalid->extra1 (array value limit) */ FT_LOCAL_DEF( void ) otv_x_ux_y_uy_z_uz_p_sp( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt BacktrackCount, InputCount, LookaheadCount; FT_UInt Count; OTV_ENTER; OTV_LIMIT_CHECK( 2 ); BacktrackCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (BacktrackCount = %d)\n", BacktrackCount )); OTV_LIMIT_CHECK( BacktrackCount * 2 + 2 ); p += BacktrackCount * 2; InputCount = FT_NEXT_USHORT( p ); if ( InputCount == 0 ) FT_INVALID_DATA; OTV_TRACE(( " (InputCount = %d)\n", InputCount )); OTV_LIMIT_CHECK( InputCount * 2 ); p += ( InputCount - 1 ) * 2; LookaheadCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (LookaheadCount = %d)\n", LookaheadCount )); OTV_LIMIT_CHECK( LookaheadCount * 2 + 2 ); p += LookaheadCount * 2; Count = FT_NEXT_USHORT( p ); OTV_TRACE(( " (Count = %d)\n", Count )); OTV_LIMIT_CHECK( Count * 4 ); for ( ; Count > 0; Count-- ) { if ( FT_NEXT_USHORT( p ) >= InputCount ) FT_INVALID_DATA; if ( FT_NEXT_USHORT( p ) >= otvalid->extra1 ) FT_INVALID_DATA; } OTV_EXIT; } /* sets otvalid->extra1 (valid->lookup_count) */ FT_LOCAL_DEF( void ) otv_u_O_O_x_Onx( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt Coverage, ClassDef, ClassSetCount; OTV_Validate_Func func; OTV_ENTER; p += 2; /* skip Format */ OTV_LIMIT_CHECK( 6 ); Coverage = FT_NEXT_USHORT( p ); ClassDef = FT_NEXT_USHORT( p ); ClassSetCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (ClassSetCount = %d)\n", ClassSetCount )); otv_Coverage_validate( table + Coverage, otvalid, -1 ); otv_ClassDef_validate( table + ClassDef, otvalid ); OTV_LIMIT_CHECK( ClassSetCount * 2 ); otvalid->nesting_level++; func = otvalid->func[otvalid->nesting_level]; otvalid->extra1 = otvalid->lookup_count; for ( ; ClassSetCount > 0; ClassSetCount-- ) { FT_UInt offset = FT_NEXT_USHORT( p ); if ( offset ) func( table + offset, otvalid ); } otvalid->nesting_level--; OTV_EXIT; } /* uses otvalid->lookup_count */ FT_LOCAL_DEF( void ) otv_u_x_y_Ox_sy( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt GlyphCount, Count, count1; OTV_ENTER; p += 2; /* skip Format */ OTV_LIMIT_CHECK( 4 ); GlyphCount = FT_NEXT_USHORT( p ); Count = FT_NEXT_USHORT( p ); OTV_TRACE(( " (GlyphCount = %d)\n", GlyphCount )); OTV_TRACE(( " (Count = %d)\n", Count )); OTV_LIMIT_CHECK( GlyphCount * 2 + Count * 4 ); for ( count1 = GlyphCount; count1 > 0; count1-- ) otv_Coverage_validate( table + FT_NEXT_USHORT( p ), otvalid, -1 ); for ( ; Count > 0; Count-- ) { if ( FT_NEXT_USHORT( p ) >= GlyphCount ) FT_INVALID_DATA; if ( FT_NEXT_USHORT( p ) >= otvalid->lookup_count ) FT_INVALID_DATA; } OTV_EXIT; } /* sets otvalid->extra1 (valid->lookup_count) */ FT_LOCAL_DEF( void ) otv_u_O_O_O_O_x_Onx( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt Coverage; FT_UInt BacktrackClassDef, InputClassDef, LookaheadClassDef; FT_UInt ChainClassSetCount; OTV_Validate_Func func; OTV_ENTER; p += 2; /* skip Format */ OTV_LIMIT_CHECK( 10 ); Coverage = FT_NEXT_USHORT( p ); BacktrackClassDef = FT_NEXT_USHORT( p ); InputClassDef = FT_NEXT_USHORT( p ); LookaheadClassDef = FT_NEXT_USHORT( p ); ChainClassSetCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (ChainClassSetCount = %d)\n", ChainClassSetCount )); otv_Coverage_validate( table + Coverage, otvalid, -1 ); otv_ClassDef_validate( table + BacktrackClassDef, otvalid ); otv_ClassDef_validate( table + InputClassDef, otvalid ); otv_ClassDef_validate( table + LookaheadClassDef, otvalid ); OTV_LIMIT_CHECK( ChainClassSetCount * 2 ); otvalid->nesting_level++; func = otvalid->func[otvalid->nesting_level]; otvalid->extra1 = otvalid->lookup_count; for ( ; ChainClassSetCount > 0; ChainClassSetCount-- ) { FT_UInt offset = FT_NEXT_USHORT( p ); if ( offset ) func( table + offset, otvalid ); } otvalid->nesting_level--; OTV_EXIT; } /* uses otvalid->lookup_count */ FT_LOCAL_DEF( void ) otv_u_x_Ox_y_Oy_z_Oz_p_sp( FT_Bytes table, OTV_Validator otvalid ) { FT_Bytes p = table; FT_UInt BacktrackGlyphCount, InputGlyphCount, LookaheadGlyphCount; FT_UInt count1, count2; OTV_ENTER; p += 2; /* skip Format */ OTV_LIMIT_CHECK( 2 ); BacktrackGlyphCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (BacktrackGlyphCount = %d)\n", BacktrackGlyphCount )); OTV_LIMIT_CHECK( BacktrackGlyphCount * 2 + 2 ); for ( ; BacktrackGlyphCount > 0; BacktrackGlyphCount-- ) otv_Coverage_validate( table + FT_NEXT_USHORT( p ), otvalid, -1 ); InputGlyphCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (InputGlyphCount = %d)\n", InputGlyphCount )); OTV_LIMIT_CHECK( InputGlyphCount * 2 + 2 ); for ( count1 = InputGlyphCount; count1 > 0; count1-- ) otv_Coverage_validate( table + FT_NEXT_USHORT( p ), otvalid, -1 ); LookaheadGlyphCount = FT_NEXT_USHORT( p ); OTV_TRACE(( " (LookaheadGlyphCount = %d)\n", LookaheadGlyphCount )); OTV_LIMIT_CHECK( LookaheadGlyphCount * 2 + 2 ); for ( ; LookaheadGlyphCount > 0; LookaheadGlyphCount-- ) otv_Coverage_validate( table + FT_NEXT_USHORT( p ), otvalid, -1 ); count2 = FT_NEXT_USHORT( p ); OTV_TRACE(( " (Count = %d)\n", count2 )); OTV_LIMIT_CHECK( count2 * 4 ); for ( ; count2 > 0; count2-- ) { if ( FT_NEXT_USHORT( p ) >= InputGlyphCount ) FT_INVALID_DATA; if ( FT_NEXT_USHORT( p ) >= otvalid->lookup_count ) FT_INVALID_DATA; } OTV_EXIT; } FT_LOCAL_DEF( FT_UInt ) otv_GSUBGPOS_get_Lookup_count( FT_Bytes table ) { FT_Bytes p = table + 8; return otv_LookupList_get_count( table + FT_NEXT_USHORT( p ) ); } FT_LOCAL_DEF( FT_UInt ) otv_GSUBGPOS_have_MarkAttachmentType_flag( FT_Bytes table ) { FT_Bytes p, lookup; FT_UInt count; if ( !table ) return 0; /* LookupList */ p = table + 8; table += FT_NEXT_USHORT( p ); /* LookupCount */ p = table; count = FT_NEXT_USHORT( p ); for ( ; count > 0; count-- ) { FT_Bytes oldp; /* Lookup */ lookup = table + FT_NEXT_USHORT( p ); oldp = p; /* LookupFlag */ p = lookup + 2; if ( FT_NEXT_USHORT( p ) & 0xFF00U ) return 1; p = oldp; } return 0; } /* END */