projects / apple / icu.git / blame
| Commit | Line | Data |
|---|---|---|
| b75a7d8f | 1 | /* |
| 46f4442e | 2 | * (C) Copyright IBM Corp. 1998-2008 - All Rights Reserved |
| b75a7d8f A |
3 | * |
| 4 | */ | |
| 5 | ||
| 6 | #include "LETypes.h" | |
| 7 | #include "OpenTypeTables.h" | |
| 8 | #include "OpenTypeUtilities.h" | |
| 9 | #include "ScriptAndLanguage.h" | |
| 10 | #include "LESwaps.h" | |
| 11 | ||
| 12 | U_NAMESPACE_BEGIN | |
| 13 | ||
| 14 | const LangSysTable *ScriptTable::findLanguage(LETag languageTag, le_bool exactMatch) const | |
| 15 | { | |
| 16 | le_uint16 count = SWAPW(langSysCount); | |
| 17 | Offset langSysTableOffset = exactMatch? 0 : SWAPW(defaultLangSysTableOffset); | |
| 18 | ||
| 19 | if (count > 0) { | |
| 20 | Offset foundOffset = | |
| 21 | OpenTypeUtilities::getTagOffset(languageTag, langSysRecordArray, count); | |
| 22 | ||
| 23 | if (foundOffset != 0) { | |
| 24 | langSysTableOffset = foundOffset; | |
| 25 | } | |
| 26 | } | |
| 27 | ||
| 28 | if (langSysTableOffset != 0) { | |
| 29 | return (const LangSysTable *) ((char *)this + langSysTableOffset); | |
| 30 | } | |
| 31 | ||
| 46f4442e | 32 | return NULL; |
| b75a7d8f A |
33 | } |
| 34 | ||
| 35 | const ScriptTable *ScriptListTable::findScript(LETag scriptTag) const | |
| 36 | { | |
| 46f4442e A |
37 | /* |
| 38 | * There are some fonts that have a large, bogus value for scriptCount. To try | |
| 39 | * and protect against this, we use the offset in the first scriptRecord, | |
| 40 | * which we know has to be past the end of the scriptRecordArray, to compute | |
| 41 | * a value which is greater than or equal to the actual script count. | |
| 42 | * | |
| 43 | * Note: normally, the first offset will point to just after the scriptRecordArray, | |
| 44 | * but there's no guarantee of this, only that it's *after* the scriptRecordArray. | |
| 45 | * Because of this, a binary serach isn't safe, because the new count may include | |
| 46 | * data that's not actually in the scriptRecordArray and hence the array will appear | |
| 47 | * to be unsorted. | |
| 48 | */ | |
| b75a7d8f | 49 | le_uint16 count = SWAPW(scriptCount); |
| 46f4442e A |
50 | le_uint16 limit = ((SWAPW(scriptRecordArray[0].offset) - sizeof(ScriptListTable)) / sizeof(scriptRecordArray)) + ANY_NUMBER; |
| 51 | Offset scriptTableOffset = 0; | |
| 52 | ||
| 53 | if (count > limit) { | |
| 54 | // the scriptCount value is bogus; do a linear search | |
| 55 | // because limit may still be too large. | |
| 56 | for(le_int32 s = 0; s < limit; s += 1) { | |
| 57 | if (SWAPT(scriptRecordArray[s].tag) == scriptTag) { | |
| 58 | scriptTableOffset = SWAPW(scriptRecordArray[s].offset); | |
| 59 | break; | |
| 60 | } | |
| 61 | } | |
| 62 | } else { | |
| 63 | scriptTableOffset = OpenTypeUtilities::getTagOffset(scriptTag, scriptRecordArray, count); | |
| 64 | } | |
| b75a7d8f A |
65 | |
| 66 | if (scriptTableOffset != 0) { | |
| 67 | return (const ScriptTable *) ((char *)this + scriptTableOffset); | |
| 68 | } | |
| 69 | ||
| 46f4442e | 70 | return NULL; |
| b75a7d8f A |
71 | } |
| 72 | ||
| 73 | const LangSysTable *ScriptListTable::findLanguage(LETag scriptTag, LETag languageTag, le_bool exactMatch) const | |
| 74 | { | |
| 75 | const ScriptTable *scriptTable = findScript(scriptTag); | |
| 76 | ||
| 77 | if (scriptTable == 0) { | |
| 46f4442e | 78 | return NULL; |
| b75a7d8f A |
79 | } |
| 80 | ||
| 81 | return scriptTable->findLanguage(languageTag, exactMatch); | |
| 82 | } | |
| 83 | ||
| 84 | U_NAMESPACE_END |