X-Git-Url: https://git.saurik.com/apple/icu.git/blobdiff_plain/b75a7d8f3b4adbae880cab104ce2c6a50eee4db2..b801cf366c7671a99bdcef84d1e9c0ec64b36723:/icuSources/layout/ScriptAndLanguage.cpp?ds=sidebyside diff --git a/icuSources/layout/ScriptAndLanguage.cpp b/icuSources/layout/ScriptAndLanguage.cpp index 80941a5d..c7818d18 100644 --- a/icuSources/layout/ScriptAndLanguage.cpp +++ b/icuSources/layout/ScriptAndLanguage.cpp @@ -1,7 +1,5 @@ /* - * %W% %E% - * - * (C) Copyright IBM Corp. 1998-2003 - All Rights Reserved + * (C) Copyright IBM Corp. 1998-2013 - All Rights Reserved * */ @@ -13,49 +11,94 @@ U_NAMESPACE_BEGIN -const LangSysTable *ScriptTable::findLanguage(LETag languageTag, le_bool exactMatch) const +LEReferenceTo ScriptTable::findLanguage(const LETableReference& base, LETag languageTag, LEErrorCode &success, le_bool exactMatch) const { le_uint16 count = SWAPW(langSysCount); Offset langSysTableOffset = exactMatch? 0 : SWAPW(defaultLangSysTableOffset); if (count > 0) { - Offset foundOffset = - OpenTypeUtilities::getTagOffset(languageTag, langSysRecordArray, count); - - if (foundOffset != 0) { - langSysTableOffset = foundOffset; - } + LEReferenceToArrayOf langSysRecords(base, success, langSysRecordArray, count); + Offset foundOffset = + OpenTypeUtilities::getTagOffset(languageTag, langSysRecords, success); + + if (foundOffset != 0 && LE_SUCCESS(success)) { + langSysTableOffset = foundOffset; + } } - + if (langSysTableOffset != 0) { - return (const LangSysTable *) ((char *)this + langSysTableOffset); + return LEReferenceTo(base, success, langSysTableOffset); } - return 0; + return LEReferenceTo(); } -const ScriptTable *ScriptListTable::findScript(LETag scriptTag) const +LEReferenceTo ScriptListTable::findScript(const LETableReference &base, LETag scriptTag, LEErrorCode &success) const { + if (LE_FAILURE(success) ) { + return LEReferenceTo(); // get out + } + /* + * There are some fonts that have a large, bogus value for scriptCount. To try + * and protect against this, we use the offset in the first scriptRecord, + * which we know has to be past the end of the scriptRecordArray, to compute + * a value which is greater than or equal to the actual script count. + * + * Note: normally, the first offset will point to just after the scriptRecordArray, + * but there's no guarantee of this, only that it's *after* the scriptRecordArray. + * Because of this, a binary serach isn't safe, because the new count may include + * data that's not actually in the scriptRecordArray and hence the array will appear + * to be unsorted. + */ le_uint16 count = SWAPW(scriptCount); - Offset scriptTableOffset = - OpenTypeUtilities::getTagOffset(scriptTag, scriptRecordArray, count); + + if (count == 0) { + return LEReferenceTo(); // no items, no search + } + + // attempt to construct a ref with at least one element + LEReferenceToArrayOf oneElementTable(base, success, &scriptRecordArray[0], 1); + + if( LE_FAILURE(success) ) { + return LEReferenceTo(); // couldn't even read the first record - bad font. + } + + le_uint16 limit = ((SWAPW(scriptRecordArray[0].offset) - sizeof(ScriptListTable)) / sizeof(scriptRecordArray)) + ANY_NUMBER; + Offset scriptTableOffset = 0; + + + if (count > limit) { + // the scriptCount value is bogus; do a linear search + // because limit may still be too large. + LEReferenceToArrayOf scriptRecordArrayRef(base, success, &scriptRecordArray[0], limit); + for(le_int32 s = 0; (s < limit)&&LE_SUCCESS(success); s += 1) { + if (SWAPT(scriptRecordArrayRef(s,success).tag) == scriptTag) { + scriptTableOffset = SWAPW(scriptRecordArrayRef(s,success).offset); + break; + } + } + } else { + LEReferenceToArrayOf scriptRecordArrayRef(base, success, &scriptRecordArray[0], count); + + scriptTableOffset = OpenTypeUtilities::getTagOffset(scriptTag, scriptRecordArrayRef, success); + } if (scriptTableOffset != 0) { - return (const ScriptTable *) ((char *)this + scriptTableOffset); + return LEReferenceTo(base, success, scriptTableOffset); } - return 0; + return LEReferenceTo(); } -const LangSysTable *ScriptListTable::findLanguage(LETag scriptTag, LETag languageTag, le_bool exactMatch) const +LEReferenceTo ScriptListTable::findLanguage(const LETableReference &base, LETag scriptTag, LETag languageTag, LEErrorCode &success, le_bool exactMatch) const { - const ScriptTable *scriptTable = findScript(scriptTag); + const LEReferenceTo scriptTable = findScript(base, scriptTag, success); - if (scriptTable == 0) { - return 0; - } + if (scriptTable.isEmpty()) { + return LEReferenceTo(); + } - return scriptTable->findLanguage(languageTag, exactMatch); + return scriptTable->findLanguage(scriptTable, languageTag, success, exactMatch).reparent(base); } U_NAMESPACE_END