/* ******************************************************************************* * Copyright (C) 1997-1999, International Business Machines Corporation and * * others. All Rights Reserved. * ******************************************************************************* * * File TIMEZONE.CPP * * Modification History: * * Date Name Description * 12/05/96 clhuang Creation. * 04/21/97 aliu General clean-up and bug fixing. * 05/08/97 aliu Fixed Hashtable code per code review. * 07/09/97 helena Changed createInstance to createDefault. * 07/29/97 aliu Updated with all-new list of 96 UNIX-derived * TimeZones. Changed mechanism to load from static * array rather than resource bundle. * 07/07/1998 srl Bugfixes from the Java side: UTC GMT CAT NST * Added getDisplayName API * going to add custom parsing. * * ISSUES: * - should getDisplayName cache something? * - should custom time zones be cached? [probably] * 08/10/98 stephen Brought getDisplayName() API in-line w/ conventions * 08/19/98 stephen Changed createTimeZone() to never return 0 * 09/02/98 stephen Added getOffset(monthLen) and hasSameRules() * 09/15/98 stephen Added getStaticClassID() * 02/22/99 stephen Removed character literals for EBCDIC safety * 05/04/99 stephen Changed initDefault() for Mutex issues * 07/12/99 helena HPUX 11 CC Port. * 12/03/99 aliu Moved data out of static table into icudata.dll. * Substantial rewrite of zone lookup, default zone, and * available IDs code. Misc. cleanup. *********************************************************************************/ #include "unicode/simpletz.h" #include "unicode/smpdtfmt.h" #include "unicode/calendar.h" #include "mutex.h" #include "unicode/udata.h" #include "tzdat.h" #include "cstring.h" #ifdef _DEBUG #include "unistrm.h" #endif // static initialization char TimeZone::fgClassID = 0; // Value is irrelevant TimeZone* TimeZone::fgDefaultZone = NULL; const UnicodeString TimeZone::GMT_ID = UNICODE_STRING("GMT", 3); const int32_t TimeZone::GMT_ID_LENGTH = 3; const UnicodeString TimeZone::CUSTOM_ID = UNICODE_STRING("Custom", 6); const TimeZone* TimeZone::GMT = new SimpleTimeZone(0, GMT_ID); // See header file for documentation of the following const TZHeader * TimeZone::DATA = 0; const uint32_t* TimeZone::INDEX_BY_ID = 0; const OffsetIndex* TimeZone::INDEX_BY_OFFSET = 0; UnicodeString* TimeZone::ZONE_IDS = 0; bool_t TimeZone::DATA_LOADED = FALSE; UMTX TimeZone::LOCK; /** * Attempt to load the system zone data from icudata.dll (or its * equivalent). After this call returns DATA_LOADED will be true. * DATA itself will be non-null if the load succeeded; otherwise it * will be null. This call does nothing if the load has already * happened or or if it happens in another thread concurrently before * we can get there. * * After this call, we are guaranteed that DATA_LOADED is true. We * are _not_ guaranteed that DATA will be nonzero. If it is nonzero, * we are guaranteed that all associated data structures are * initialized. */ void TimeZone::loadZoneData() { if (!DATA_LOADED) { Mutex lock(&LOCK); if (!DATA_LOADED) { UErrorCode status = U_ZERO_ERROR; UDataMemory *data = udata_openChoice(0, TZ_DATA_TYPE, TZ_DATA_NAME, isDataAcceptable, 0, &status); if (U_SUCCESS(status)) { DATA = (TZHeader*)udata_getMemory(data); // Result guaranteed to be nonzero if data is nonzero // We require that standard zones occur before DST // zones. Do a quick check for this here, and if the // check fails, don't use this zone data. // (Alternatively, we could handle either ordering, // with a little extra logic.) See // createSystemTimeZone(). if (DATA->standardDelta > DATA->dstDelta) { DATA = 0; } else { INDEX_BY_ID = (const uint32_t*)((int8_t*)DATA + DATA->nameIndexDelta); INDEX_BY_OFFSET = (const OffsetIndex*)((int8_t*)DATA + DATA->offsetIndexDelta); // Construct the available IDs array. The ordering // of this array conforms to the ordering of the // index by name table. ZONE_IDS = new UnicodeString[DATA->count]; // Find start of name table, and walk through it // linearly. If you're wondering why we don't use // the INDEX_BY_ID, it's because that indexes the // zone objects, not the name table. The name // table is unindexed. const char* name = (const char*)DATA + DATA->nameTableDelta; for (uint32_t i=0; icount; ++i) { ZONE_IDS[i] = UnicodeString(name, ""); // invariant converter name += uprv_strlen(name) + 1; } } } // Whether we succeed or fail, stop future attempts DATA_LOADED = TRUE; } } } /** * udata callback to verify the zone data. */ bool_t U_CALLCONV TimeZone::isDataAcceptable(void *context, const char *type, const char *name, UDataInfo *pInfo) { return pInfo->size >= sizeof(UDataInfo) && pInfo->isBigEndian == U_IS_BIG_ENDIAN && pInfo->charsetFamily == U_CHARSET_FAMILY && pInfo->dataFormat[0] == 0x7a && // see TZ_SIG, must be numeric literals to be portable pInfo->dataFormat[1] == 0x6f && // (this is not a string, it just looks like one for debugging) pInfo->dataFormat[2] == 0x6e && pInfo->dataFormat[3] == 0x65 && pInfo->formatVersion[0] == TZ_FORMAT_VERSION; } // ***************************************************************************** // class TimeZone // ***************************************************************************** TimeZone::TimeZone() { } // ------------------------------------- TimeZone::~TimeZone() { } // ------------------------------------- TimeZone::TimeZone(const TimeZone &source) : fID(source.fID) { } // ------------------------------------- TimeZone & TimeZone::operator=(const TimeZone &right) { if (this != &right) fID = right.fID; return *this; } // ------------------------------------- bool_t TimeZone::operator==(const TimeZone& that) const { return getDynamicClassID() == that.getDynamicClassID() && fID == that.fID; } // ------------------------------------- TimeZone* TimeZone::createTimeZone(const UnicodeString& ID) { /* We first try to lookup the zone ID in our system list. If this * fails, we try to parse it as a custom string GMT[+-]hh:mm. If * all else fails, we return GMT, which is probably not what the * user wants, but at least is a functioning TimeZone object. */ TimeZone* result = 0; if (!DATA_LOADED) { loadZoneData(); } if (DATA != 0) { result = createSystemTimeZone(ID); } if (result == 0) { result = createCustomTimeZone(ID); } if (result == 0) { result = GMT->clone(); } return result; } /** * Lookup the given name in our system zone table. If found, * instantiate a new zone of that name and return it. If not * found, return 0. */ TimeZone* TimeZone::createSystemTimeZone(const UnicodeString& name) { if (0 == DATA) { return 0; } // Perform a binary search. Possible optimization: Unroll the // search. Not worth it given the small number of zones (416 in // 1999j). uint32_t low = 0; uint32_t high = DATA->count; while (high > low) { // Invariant: match, if present, must be in the range [low, // high). uint32_t i = (low + high) / 2; int8_t c = name.compare(ZONE_IDS[i]); if (c == 0) { const int8_t* z = (int8_t*)DATA + INDEX_BY_ID[i]; // NOTE: standard zones must be before DST zones. We test // for this when loading up the data; see loadZoneData(). return INDEX_BY_ID[i] < DATA->dstDelta ? new SimpleTimeZone(*(const StandardZone*)z, name) : new SimpleTimeZone(*(const DSTZone*)z, name); } else if (c < 0) { high = i; } else { low = i + 1; } } return 0; } // ------------------------------------- void TimeZone::initDefault() { if (!DATA_LOADED) { loadZoneData(); } // This function is called by createDefault() to initialize // fgDefaultZone from the system default time zone. If // fgDefaultZone is already filled in, we obviously don't have to // do anything. if (fgDefaultZone == 0) { Mutex lock(&LOCK); if (fgDefaultZone == 0) { // We access system timezone data through TPlatformUtilities, // including tzset(), timezone, and tzname[]. int32_t rawOffset = 0; const char *hostID; // First, try to create a system timezone, based // on the string ID in tzname[0]. { // NOTE: Global mutex here; TimeZone mutex above Mutex lock; // mutexed to avoid threading issues in the platform fcns. uprv_tzset(); // Initialize tz... system data // get the timezone ID from the host. hostID = uprv_tzname(0); // Invert sign because UNIX semantics are backwards rawOffset = uprv_timezone() * -U_MILLIS_PER_SECOND; } // Try to create a system zone with the given ID. This // _always fails on Windows_ because Windows returns a // non-standard localized zone name, e.g., "Pacific // Standard Time" on U.S. systems set to PST. One way to // fix this is to add a Windows-specific mapping table, // but that means we'd have to do so for every locale. A // better way is to use the offset and find a // corresponding zone, which is what we do below. fgDefaultZone = createSystemTimeZone(hostID); // If we couldn't get the time zone ID from the host, use // the default host timezone offset. Further refinements // to this include querying the host to determine if DST // is in use or not and possibly using the host locale to // select from multiple zones at a the same offset. We // don't do any of this now, but we could easily add this. if (fgDefaultZone == 0 && DATA != 0) { // Use the designated default in the time zone list that has the // appropriate GMT offset, if there is one. const OffsetIndex* index = INDEX_BY_OFFSET; for (;;) { if (index->gmtOffset > rawOffset) { // Went past our desired offset; no match found break; } if (index->gmtOffset == rawOffset) { // Found our desired offset fgDefaultZone = createTimeZone(ZONE_IDS[index->defaultZone]); break; } // Compute the position of the next entry. If the delta value // in this entry is zero, then there is no next entry. uint16_t delta = index->nextEntryDelta; if (delta == 0) { break; } index = (const OffsetIndex*)((int8_t*)index + delta); } } // If we _still_ don't have a time zone, use GMT. This // can only happen if the raw offset returned by // uprv_timezone() does not correspond to any system zone. if (fgDefaultZone == 0) { fgDefaultZone = GMT->clone(); } } } } // ------------------------------------- TimeZone* TimeZone::createDefault() { initDefault(); // After this call fgDefaultZone is not NULL Mutex lock(&LOCK); // In case adoptDefault is called return fgDefaultZone->clone(); } // ------------------------------------- void TimeZone::adoptDefault(TimeZone* zone) { if (zone != NULL) { Mutex mutex(&LOCK); if (fgDefaultZone != NULL) { delete fgDefaultZone; } fgDefaultZone = zone; } } // ------------------------------------- void TimeZone::setDefault(const TimeZone& zone) { adoptDefault(zone.clone()); } // ------------------------------------- const UnicodeString** const TimeZone::createAvailableIDs(int32_t rawOffset, int32_t& numIDs) { // We are creating a new array to existing UnicodeString pointers. // The caller will delete the array when done, but not the pointers // in the array. if (!DATA_LOADED) { loadZoneData(); } if (0 == DATA) { numIDs = 0; return 0; } /* The offset index table is a table of variable-sized objects. * Each entry has an offset to the next entry; the last entry has * a next entry offset of zero. * * The entries are sorted in ascending numerical order of GMT * offset. Each entry lists all the system zones at that offset, * in lexicographic order of ID. Note that this ordering is * somewhat significant in that the _first_ zone in each list is * what will be chosen as the default under certain fallback * conditions. We currently just let that be the * lexicographically first zone, but we could also adjust the list * to pick which zone was first for this situation -- probably not * worth the trouble, except for the fact that this fallback is * _always_ used to determine the default zone on Windows. * * The list of zones is actually just a list of integers, from * 0..n-1, where n is the total number of system zones. The * numbering corresponds exactly to the ordering of ZONE_IDS. */ const OffsetIndex* index = INDEX_BY_OFFSET; for (;;) { if (index->gmtOffset > rawOffset) { // Went past our desired offset; no match found break; } if (index->gmtOffset == rawOffset) { // Found our desired offset const UnicodeString** const result = (const UnicodeString** const) new UnicodeString*[index->count]; const uint16_t* zoneNumberArray = &(index->zoneNumber); for (uint16_t i=0; icount; ++i) { // Pointer assignment - use existing UnicodeString object! // Don't create a new UnicodeString on the heap here! result[i] = &ZONE_IDS[zoneNumberArray[i]]; } numIDs = index->count; return result; } // Compute the position of the next entry. If the delta value // in this entry is zero, then there is no next entry. uint16_t delta = index->nextEntryDelta; if (delta == 0) { break; } index = (const OffsetIndex*)((int8_t*)index + delta); } numIDs = 0; return 0; } // ------------------------------------- const UnicodeString** const TimeZone::createAvailableIDs(int32_t& numIDs) { // We are creating a new array to existing UnicodeString pointers. // The caller will delete the array when done, but not the pointers // in the array. // // This is really unnecessary, given the fact that we have an // array of the IDs already constructed, and we could just return // that. However, that would be a breaking API change, and some // callers familiar with the original API might try to delete it. if (!DATA_LOADED) { loadZoneData(); } if (0 == DATA) { numIDs = 0; return 0; } const UnicodeString** const result = (const UnicodeString** const) new UnicodeString*[DATA->count]; // Create a list of pointers to each and every zone ID for (uint32_t i=0; icount; ++i) { // Pointer assignment - use existing UnicodeString object! // Don't create a new UnicodeString on the heap here! result[i] = &ZONE_IDS[i]; } numIDs = DATA->count; return result; } // --------------------------------------- UnicodeString& TimeZone::getDisplayName(UnicodeString& result) const { return getDisplayName(FALSE,LONG,Locale::getDefault(), result); } UnicodeString& TimeZone::getDisplayName(const Locale& locale, UnicodeString& result) const { return getDisplayName(FALSE, LONG, locale, result); } UnicodeString& TimeZone::getDisplayName(bool_t daylight, EDisplayType style, UnicodeString& result) const { return getDisplayName(daylight,style, Locale::getDefault(), result); } UnicodeString& TimeZone::getDisplayName(bool_t daylight, EDisplayType style, const Locale& locale, UnicodeString& result) const { // SRL TODO: cache the SDF, just like java. UErrorCode status = U_ZERO_ERROR; SimpleDateFormat format(style == LONG ? "zzzz" : "z",locale,status); if(!U_SUCCESS(status)) { // *** SRL what do I do here?!! return result.remove(); } // Create a new SimpleTimeZone as a stand-in for this zone; the // stand-in will have no DST, or all DST, but the same ID and offset, // and hence the same display name. // We don't cache these because they're small and cheap to create. UnicodeString tempID; SimpleTimeZone *tz = daylight ? // For the pure-DST zone, we use JANUARY and DECEMBER new SimpleTimeZone(getRawOffset(), getID(tempID), Calendar::JANUARY , 1, 0, 0, Calendar::DECEMBER , 31, 0, U_MILLIS_PER_DAY, status) : new SimpleTimeZone(getRawOffset(), getID(tempID)); format.applyPattern(style == LONG ? "zzzz" : "z"); Calendar *myCalendar = (Calendar*)format.getCalendar(); myCalendar->setTimeZone(*tz); // copy delete tz; FieldPosition pos(FieldPosition::DONT_CARE); return format.format(UDate(196262345678.), result, pos); // Must use a valid date here. } /** * Parse a custom time zone identifier and return a corresponding zone. * @param id a string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or * GMT[+-]hh. * @return a newly created SimpleTimeZone with the given offset and * no Daylight Savings Time, or null if the id cannot be parsed. */ TimeZone* TimeZone::createCustomTimeZone(const UnicodeString& id) { static const int32_t kParseFailed = -99999; NumberFormat* numberFormat = 0; UnicodeString idUppercase = id; idUppercase.toUpper(); if (id.length() > GMT_ID_LENGTH && idUppercase.startsWith(GMT_ID)) { ParsePosition pos(GMT_ID_LENGTH); bool_t negative = FALSE; int32_t offset; if (id[pos.getIndex()] == 0x002D /*'-'*/) negative = TRUE; else if (id[pos.getIndex()] != 0x002B /*'+'*/) return 0; pos.setIndex(pos.getIndex() + 1); UErrorCode success = U_ZERO_ERROR; numberFormat = NumberFormat::createInstance(success); numberFormat->setParseIntegerOnly(TRUE); // Look for either hh:mm, hhmm, or hh int32_t start = pos.getIndex(); Formattable n(kParseFailed); numberFormat->parse(id, n, pos); if (pos.getIndex() == start) return 0; offset = n.getLong(); if (pos.getIndex() < id.length() && id[pos.getIndex()] == 0x003A /*':'*/) { // hh:mm offset *= 60; pos.setIndex(pos.getIndex() + 1); int32_t oldPos = pos.getIndex(); n.setLong(kParseFailed); numberFormat->parse(id, n, pos); if (pos.getIndex() == oldPos) return 0; offset += n.getLong(); } else { // hhmm or hh // Be strict about interpreting something as hh; it must be // an offset < 30, and it must be one or two digits. Thus // 0010 is interpreted as 00:10, but 10 is interpreted as // 10:00. if (offset < 30 && (pos.getIndex() - start) <= 2) offset *= 60; // hh, from 00 to 29; 30 is 00:30 else offset = offset % 100 + offset / 100 * 60; // hhmm } if(negative) offset = -offset; return new SimpleTimeZone(offset * 60000, CUSTOM_ID); delete numberFormat; } return 0; } bool_t TimeZone::hasSameRules(const TimeZone& other) const { return (getRawOffset() == other.getRawOffset() && useDaylightTime() == other.useDaylightTime()); } //eof