| /***************************************************************************/ |
| /* */ |
| /* gxvmort.c */ |
| /* */ |
| /* TrueTypeGX/AAT mort table validation (body). */ |
| /* */ |
| /* Copyright 2005 by suzuki toshiya, Masatake YAMATO, Red Hat K.K., */ |
| /* 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. */ |
| /* */ |
| /***************************************************************************/ |
| |
| /***************************************************************************/ |
| /* */ |
| /* gxvalid is derived from both gxlayout module and otvalid module. */ |
| /* Development of gxlayout is supported by the Information-technology */ |
| /* Promotion Agency(IPA), Japan. */ |
| /* */ |
| /***************************************************************************/ |
| |
| |
| #include "gxvmort.h" |
| #include "gxvfeat.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 trace_gxvmort |
| |
| |
| static void |
| gxv_mort_feature_validate( GXV_mort_feature f, |
| GXV_Validator valid ) |
| { |
| if ( f->featureType >= gxv_feat_registry_length ) |
| { |
| GXV_TRACE(( "featureType %d is out of registered range, " |
| "setting %d is unchecked\n", |
| f->featureType, f->featureSetting )); |
| if ( valid->root->level >= FT_VALIDATE_PARANOID ) |
| FT_INVALID_DATA; |
| } |
| else if ( !gxv_feat_registry[f->featureType].existence ) |
| { |
| GXV_TRACE(( "featureType %d is within registered area " |
| "but undefined, setting %d is unchecked\n", |
| f->featureType, f->featureSetting )); |
| if ( valid->root->level >= FT_VALIDATE_PARANOID ) |
| FT_INVALID_DATA; |
| } |
| else |
| { |
| FT_Byte nSettings_max; |
| |
| |
| /* nSettings in gxvfeat.c is halved for exclusive on/off settings */ |
| nSettings_max = gxv_feat_registry[f->featureType].nSettings; |
| if ( gxv_feat_registry[f->featureType].exclusive ) |
| nSettings_max = (FT_Byte)( 2 * nSettings_max ); |
| |
| GXV_TRACE(( "featureType %d is registered", f->featureType )); |
| GXV_TRACE(( "setting %d", f->featureSetting )); |
| |
| if ( f->featureSetting > nSettings_max ) |
| { |
| GXV_TRACE(( "out of defined range %d", nSettings_max )); |
| if ( valid->root->level >= FT_VALIDATE_PARANOID ) |
| FT_INVALID_DATA; |
| } |
| GXV_TRACE(( "\n" )); |
| } |
| |
| /* TODO: enableFlags must be unique value in specified chain? */ |
| } |
| |
| |
| /* |
| * nFeatureFlags is typed to FT_UInt to accept that in |
| * mort (typed FT_UShort) and morx (typed FT_ULong). |
| */ |
| FT_LOCAL_DEF( void ) |
| gxv_mort_featurearray_validate( FT_Bytes table, |
| FT_Bytes limit, |
| FT_UInt nFeatureFlags, |
| GXV_Validator valid ) |
| { |
| FT_Bytes p = table; |
| FT_UInt i; |
| |
| GXV_mort_featureRec f = GXV_MORT_FEATURE_OFF; |
| |
| |
| GXV_NAME_ENTER( "mort feature list" ); |
| for ( i = 0; i < nFeatureFlags; i++ ) |
| { |
| GXV_LIMIT_CHECK( 2 + 2 + 4 + 4 ); |
| f.featureType = FT_NEXT_USHORT( p ); |
| f.featureSetting = FT_NEXT_USHORT( p ); |
| f.enableFlags = FT_NEXT_ULONG( p ); |
| f.disableFlags = FT_NEXT_ULONG( p ); |
| |
| gxv_mort_feature_validate( &f, valid ); |
| } |
| |
| if ( !IS_GXV_MORT_FEATURE_OFF( f ) ) |
| FT_INVALID_DATA; |
| |
| valid->subtable_length = p - table; |
| GXV_EXIT; |
| } |
| |
| |
| FT_LOCAL_DEF( void ) |
| gxv_mort_coverage_validate( FT_UShort coverage, |
| GXV_Validator valid ) |
| { |
| FT_UNUSED( valid ); |
| |
| if ( coverage & 0x8000U ) |
| GXV_TRACE(( " this subtable is for vertical text only\n" )); |
| else |
| GXV_TRACE(( " this subtable is for horizontal text only\n" )); |
| |
| if ( coverage & 0x4000 ) |
| GXV_TRACE(( " this subtable is applied to glyph array " |
| "in descending order\n" )); |
| else |
| GXV_TRACE(( " this subtable is applied to glyph array " |
| "in ascending order\n" )); |
| |
| if ( coverage & 0x2000 ) |
| GXV_TRACE(( " this subtable is forcibly applied to " |
| "vertical/horizontal text\n" )); |
| |
| if ( coverage & 0x1FF8 ) |
| GXV_TRACE(( " coverage has non-zero bits in reserved area\n" )); |
| } |
| |
| |
| static void |
| gxv_mort_subtables_validate( FT_Bytes table, |
| FT_Bytes limit, |
| FT_UShort nSubtables, |
| GXV_Validator valid ) |
| { |
| FT_Bytes p = table; |
| |
| GXV_Validate_Func fmt_funcs_table[] = |
| { |
| gxv_mort_subtable_type0_validate, /* 0 */ |
| gxv_mort_subtable_type1_validate, /* 1 */ |
| gxv_mort_subtable_type2_validate, /* 2 */ |
| NULL, /* 3 */ |
| gxv_mort_subtable_type4_validate, /* 4 */ |
| gxv_mort_subtable_type5_validate, /* 5 */ |
| |
| }; |
| |
| GXV_Validate_Func func; |
| FT_UShort i; |
| |
| |
| GXV_NAME_ENTER( "subtables in a chain" ); |
| |
| for ( i = 0; i < nSubtables; i++ ) |
| { |
| FT_UShort length; |
| FT_UShort coverage; |
| FT_ULong subFeatureFlags; |
| FT_UInt type; |
| FT_UInt rest; |
| |
| |
| GXV_LIMIT_CHECK( 2 + 2 + 4 ); |
| length = FT_NEXT_USHORT( p ); |
| coverage = FT_NEXT_USHORT( p ); |
| subFeatureFlags = FT_NEXT_ULONG( p ); |
| |
| GXV_TRACE(( "validating chain subtable %d/%d (%d bytes)\n", |
| i + 1, nSubtables, length )); |
| type = coverage & 0x0007; |
| rest = length - ( 2 + 2 + 4 ); |
| |
| GXV_LIMIT_CHECK( rest ); |
| gxv_mort_coverage_validate( coverage, valid ); |
| |
| if ( type > 5 ) |
| FT_INVALID_FORMAT; |
| |
| func = fmt_funcs_table[type]; |
| if ( func == NULL ) |
| GXV_TRACE(( "morx type %d is reserved\n", type )); |
| |
| func( p, p + rest, valid ); |
| |
| p += rest; |
| } |
| |
| valid->subtable_length = p - table; |
| |
| GXV_EXIT; |
| } |
| |
| |
| static void |
| gxv_mort_chain_validate( FT_Bytes table, |
| FT_Bytes limit, |
| GXV_Validator valid ) |
| { |
| FT_Bytes p = table; |
| FT_ULong defaultFlags; |
| FT_ULong chainLength; |
| FT_UShort nFeatureFlags; |
| FT_UShort nSubtables; |
| |
| |
| GXV_NAME_ENTER( "mort chain header" ); |
| |
| GXV_LIMIT_CHECK( 4 + 4 + 2 + 2 ); |
| defaultFlags = FT_NEXT_ULONG( p ); |
| chainLength = FT_NEXT_ULONG( p ); |
| nFeatureFlags = FT_NEXT_USHORT( p ); |
| nSubtables = FT_NEXT_USHORT( p ); |
| |
| gxv_mort_featurearray_validate( p, table + chainLength, |
| nFeatureFlags, valid ); |
| p += valid->subtable_length; |
| gxv_mort_subtables_validate( p, table + chainLength, nSubtables, valid ); |
| valid->subtable_length = chainLength; |
| |
| GXV_EXIT; |
| } |
| |
| |
| FT_LOCAL_DEF( void ) |
| gxv_mort_validate( FT_Bytes table, |
| FT_Face face, |
| FT_Validator ftvalid ) |
| { |
| GXV_ValidatorRec validrec; |
| GXV_Validator valid = &validrec; |
| FT_Bytes p = table; |
| FT_Bytes limit = 0; |
| FT_ULong version; |
| FT_ULong nChains; |
| FT_ULong i; |
| |
| |
| valid->root = ftvalid; |
| valid->face = face; |
| limit = valid->root->limit; |
| |
| FT_TRACE3(( "validating `mort' table\n" )); |
| GXV_INIT; |
| |
| GXV_LIMIT_CHECK( 4 + 4 ); |
| version = FT_NEXT_ULONG( p ); |
| nChains = FT_NEXT_ULONG( p ); |
| |
| if (version != 0x00010000UL) |
| FT_INVALID_FORMAT; |
| |
| for ( i = 0; i < nChains; i++ ) |
| { |
| GXV_TRACE(( "validating chain %d/%d\n", i + 1, nChains )); |
| GXV_32BIT_ALIGNMENT_VALIDATE( p - table ); |
| gxv_mort_chain_validate( p, limit, valid ); |
| p += valid->subtable_length; |
| } |
| |
| FT_TRACE4(( "\n" )); |
| } |
| |
| |
| /* END */ |