/modules/freetype2/src/gxvalid/gxvmort.c
C | 285 lines | 187 code | 62 blank | 36 comment | 21 complexity | cef81604193e880b819f61ef149c23d7 MD5 | raw file
1/***************************************************************************/ 2/* */ 3/* gxvmort.c */ 4/* */ 5/* TrueTypeGX/AAT mort table validation (body). */ 6/* */ 7/* Copyright 2005 by suzuki toshiya, Masatake YAMATO, Red Hat K.K., */ 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/* */ 20/* gxvalid is derived from both gxlayout module and otvalid module. */ 21/* Development of gxlayout is supported by the Information-technology */ 22/* Promotion Agency(IPA), Japan. */ 23/* */ 24/***************************************************************************/ 25 26 27#include "gxvmort.h" 28#include "gxvfeat.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 trace_gxvmort 39 40 41 static void 42 gxv_mort_feature_validate( GXV_mort_feature f, 43 GXV_Validator valid ) 44 { 45 if ( f->featureType >= gxv_feat_registry_length ) 46 { 47 GXV_TRACE(( "featureType %d is out of registered range, " 48 "setting %d is unchecked\n", 49 f->featureType, f->featureSetting )); 50 if ( valid->root->level >= FT_VALIDATE_PARANOID ) 51 FT_INVALID_DATA; 52 } 53 else if ( !gxv_feat_registry[f->featureType].existence ) 54 { 55 GXV_TRACE(( "featureType %d is within registered area " 56 "but undefined, setting %d is unchecked\n", 57 f->featureType, f->featureSetting )); 58 if ( valid->root->level >= FT_VALIDATE_PARANOID ) 59 FT_INVALID_DATA; 60 } 61 else 62 { 63 FT_Byte nSettings_max; 64 65 66 /* nSettings in gxvfeat.c is halved for exclusive on/off settings */ 67 nSettings_max = gxv_feat_registry[f->featureType].nSettings; 68 if ( gxv_feat_registry[f->featureType].exclusive ) 69 nSettings_max = (FT_Byte)( 2 * nSettings_max ); 70 71 GXV_TRACE(( "featureType %d is registered", f->featureType )); 72 GXV_TRACE(( "setting %d", f->featureSetting )); 73 74 if ( f->featureSetting > nSettings_max ) 75 { 76 GXV_TRACE(( "out of defined range %d", nSettings_max )); 77 if ( valid->root->level >= FT_VALIDATE_PARANOID ) 78 FT_INVALID_DATA; 79 } 80 GXV_TRACE(( "\n" )); 81 } 82 83 /* TODO: enableFlags must be unique value in specified chain? */ 84 } 85 86 87 /* 88 * nFeatureFlags is typed to FT_ULong to accept that in 89 * mort (typed FT_UShort) and morx (typed FT_ULong). 90 */ 91 FT_LOCAL_DEF( void ) 92 gxv_mort_featurearray_validate( FT_Bytes table, 93 FT_Bytes limit, 94 FT_ULong nFeatureFlags, 95 GXV_Validator valid ) 96 { 97 FT_Bytes p = table; 98 FT_ULong i; 99 100 GXV_mort_featureRec f = GXV_MORT_FEATURE_OFF; 101 102 103 GXV_NAME_ENTER( "mort feature list" ); 104 for ( i = 0; i < nFeatureFlags; i++ ) 105 { 106 GXV_LIMIT_CHECK( 2 + 2 + 4 + 4 ); 107 f.featureType = FT_NEXT_USHORT( p ); 108 f.featureSetting = FT_NEXT_USHORT( p ); 109 f.enableFlags = FT_NEXT_ULONG( p ); 110 f.disableFlags = FT_NEXT_ULONG( p ); 111 112 gxv_mort_feature_validate( &f, valid ); 113 } 114 115 if ( !IS_GXV_MORT_FEATURE_OFF( f ) ) 116 FT_INVALID_DATA; 117 118 valid->subtable_length = p - table; 119 GXV_EXIT; 120 } 121 122 123 FT_LOCAL_DEF( void ) 124 gxv_mort_coverage_validate( FT_UShort coverage, 125 GXV_Validator valid ) 126 { 127 FT_UNUSED( valid ); 128 129 if ( coverage & 0x8000U ) 130 GXV_TRACE(( " this subtable is for vertical text only\n" )); 131 else 132 GXV_TRACE(( " this subtable is for horizontal text only\n" )); 133 134 if ( coverage & 0x4000 ) 135 GXV_TRACE(( " this subtable is applied to glyph array " 136 "in descending order\n" )); 137 else 138 GXV_TRACE(( " this subtable is applied to glyph array " 139 "in ascending order\n" )); 140 141 if ( coverage & 0x2000 ) 142 GXV_TRACE(( " this subtable is forcibly applied to " 143 "vertical/horizontal text\n" )); 144 145 if ( coverage & 0x1FF8 ) 146 GXV_TRACE(( " coverage has non-zero bits in reserved area\n" )); 147 } 148 149 150 static void 151 gxv_mort_subtables_validate( FT_Bytes table, 152 FT_Bytes limit, 153 FT_UShort nSubtables, 154 GXV_Validator valid ) 155 { 156 FT_Bytes p = table; 157 158 GXV_Validate_Func fmt_funcs_table[] = 159 { 160 gxv_mort_subtable_type0_validate, /* 0 */ 161 gxv_mort_subtable_type1_validate, /* 1 */ 162 gxv_mort_subtable_type2_validate, /* 2 */ 163 NULL, /* 3 */ 164 gxv_mort_subtable_type4_validate, /* 4 */ 165 gxv_mort_subtable_type5_validate, /* 5 */ 166 167 }; 168 169 GXV_Validate_Func func; 170 FT_UShort i; 171 172 173 GXV_NAME_ENTER( "subtables in a chain" ); 174 175 for ( i = 0; i < nSubtables; i++ ) 176 { 177 FT_UShort length; 178 FT_UShort coverage; 179 FT_ULong subFeatureFlags; 180 FT_UInt type; 181 FT_UInt rest; 182 183 184 GXV_LIMIT_CHECK( 2 + 2 + 4 ); 185 length = FT_NEXT_USHORT( p ); 186 coverage = FT_NEXT_USHORT( p ); 187 subFeatureFlags = FT_NEXT_ULONG( p ); 188 189 GXV_TRACE(( "validating chain subtable %d/%d (%d bytes)\n", 190 i + 1, nSubtables, length )); 191 type = coverage & 0x0007; 192 rest = length - ( 2 + 2 + 4 ); 193 194 GXV_LIMIT_CHECK( rest ); 195 gxv_mort_coverage_validate( coverage, valid ); 196 197 if ( type > 5 ) 198 FT_INVALID_FORMAT; 199 200 func = fmt_funcs_table[type]; 201 if ( func == NULL ) 202 GXV_TRACE(( "morx type %d is reserved\n", type )); 203 204 func( p, p + rest, valid ); 205 206 p += rest; 207 } 208 209 valid->subtable_length = p - table; 210 211 GXV_EXIT; 212 } 213 214 215 static void 216 gxv_mort_chain_validate( FT_Bytes table, 217 FT_Bytes limit, 218 GXV_Validator valid ) 219 { 220 FT_Bytes p = table; 221 FT_ULong defaultFlags; 222 FT_ULong chainLength; 223 FT_UShort nFeatureFlags; 224 FT_UShort nSubtables; 225 226 227 GXV_NAME_ENTER( "mort chain header" ); 228 229 GXV_LIMIT_CHECK( 4 + 4 + 2 + 2 ); 230 defaultFlags = FT_NEXT_ULONG( p ); 231 chainLength = FT_NEXT_ULONG( p ); 232 nFeatureFlags = FT_NEXT_USHORT( p ); 233 nSubtables = FT_NEXT_USHORT( p ); 234 235 gxv_mort_featurearray_validate( p, table + chainLength, 236 nFeatureFlags, valid ); 237 p += valid->subtable_length; 238 gxv_mort_subtables_validate( p, table + chainLength, nSubtables, valid ); 239 valid->subtable_length = chainLength; 240 241 GXV_EXIT; 242 } 243 244 245 FT_LOCAL_DEF( void ) 246 gxv_mort_validate( FT_Bytes table, 247 FT_Face face, 248 FT_Validator ftvalid ) 249 { 250 GXV_ValidatorRec validrec; 251 GXV_Validator valid = &validrec; 252 FT_Bytes p = table; 253 FT_Bytes limit = 0; 254 FT_ULong version; 255 FT_ULong nChains; 256 FT_ULong i; 257 258 259 valid->root = ftvalid; 260 valid->face = face; 261 limit = valid->root->limit; 262 263 FT_TRACE3(( "validating `mort' table\n" )); 264 GXV_INIT; 265 266 GXV_LIMIT_CHECK( 4 + 4 ); 267 version = FT_NEXT_ULONG( p ); 268 nChains = FT_NEXT_ULONG( p ); 269 270 if (version != 0x00010000UL) 271 FT_INVALID_FORMAT; 272 273 for ( i = 0; i < nChains; i++ ) 274 { 275 GXV_TRACE(( "validating chain %d/%d\n", i + 1, nChains )); 276 GXV_32BIT_ALIGNMENT_VALIDATE( p - table ); 277 gxv_mort_chain_validate( p, limit, valid ); 278 p += valid->subtable_length; 279 } 280 281 FT_TRACE4(( "\n" )); 282 } 283 284 285/* END */