diff options
Diffstat (limited to 'JavaScriptCore/runtime/DateMath.cpp')
| -rw-r--r-- | JavaScriptCore/runtime/DateMath.cpp | 1046 |
1 files changed, 1046 insertions, 0 deletions
diff --git a/JavaScriptCore/runtime/DateMath.cpp b/JavaScriptCore/runtime/DateMath.cpp new file mode 100644 index 0000000..ec2a3f6 --- /dev/null +++ b/JavaScriptCore/runtime/DateMath.cpp @@ -0,0 +1,1046 @@ +/* + * Copyright (C) 1999-2000 Harri Porten (porten@kde.org) + * Copyright (C) 2006, 2007 Apple Inc. All rights reserved. + * + * The Original Code is Mozilla Communicator client code, released + * March 31, 1998. + * + * The Initial Developer of the Original Code is + * Netscape Communications Corporation. + * Portions created by the Initial Developer are Copyright (C) 1998 + * the Initial Developer. All Rights Reserved. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + * + * Alternatively, the contents of this file may be used under the terms + * of either the Mozilla Public License Version 1.1, found at + * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public + * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html + * (the "GPL"), in which case the provisions of the MPL or the GPL are + * applicable instead of those above. If you wish to allow use of your + * version of this file only under the terms of one of those two + * licenses (the MPL or the GPL) and not to allow others to use your + * version of this file under the LGPL, indicate your decision by + * deletingthe provisions above and replace them with the notice and + * other provisions required by the MPL or the GPL, as the case may be. + * If you do not delete the provisions above, a recipient may use your + * version of this file under any of the LGPL, the MPL or the GPL. + */ + +#include "config.h" +#include "DateMath.h" + +#include "JSNumberCell.h" +#include <math.h> +#include <stdint.h> +#include <time.h> +#include <wtf/ASCIICType.h> +#include <wtf/Assertions.h> +#include <wtf/MathExtras.h> +#include <wtf/StringExtras.h> + +#if HAVE(ERRNO_H) +#include <errno.h> +#endif + +#if PLATFORM(DARWIN) +#include <notify.h> +#endif + +#if HAVE(SYS_TIME_H) +#include <sys/time.h> +#endif + +#if HAVE(SYS_TIMEB_H) +#include <sys/timeb.h> +#endif + +using namespace WTF; + +namespace JSC { + +/* Constants */ + +static const double minutesPerDay = 24.0 * 60.0; +static const double secondsPerDay = 24.0 * 60.0 * 60.0; +static const double secondsPerYear = 24.0 * 60.0 * 60.0 * 365.0; + +static const double usecPerSec = 1000000.0; + +static const double maxUnixTime = 2145859200.0; // 12/31/2037 + +// Day of year for the first day of each month, where index 0 is January, and day 0 is January 1. +// First for non-leap years, then for leap years. +static const int firstDayOfMonth[2][12] = { + {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334}, + {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335} +}; + +static inline bool isLeapYear(int year) +{ + if (year % 4 != 0) + return false; + if (year % 400 == 0) + return true; + if (year % 100 == 0) + return false; + return true; +} + +static inline int daysInYear(int year) +{ + return 365 + isLeapYear(year); +} + +static inline double daysFrom1970ToYear(int year) +{ + // The Gregorian Calendar rules for leap years: + // Every fourth year is a leap year. 2004, 2008, and 2012 are leap years. + // However, every hundredth year is not a leap year. 1900 and 2100 are not leap years. + // Every four hundred years, there's a leap year after all. 2000 and 2400 are leap years. + + static const int leapDaysBefore1971By4Rule = 1970 / 4; + static const int excludedLeapDaysBefore1971By100Rule = 1970 / 100; + static const int leapDaysBefore1971By400Rule = 1970 / 400; + + const double yearMinusOne = year - 1; + const double yearsToAddBy4Rule = floor(yearMinusOne / 4.0) - leapDaysBefore1971By4Rule; + const double yearsToExcludeBy100Rule = floor(yearMinusOne / 100.0) - excludedLeapDaysBefore1971By100Rule; + const double yearsToAddBy400Rule = floor(yearMinusOne / 400.0) - leapDaysBefore1971By400Rule; + + return 365.0 * (year - 1970) + yearsToAddBy4Rule - yearsToExcludeBy100Rule + yearsToAddBy400Rule; +} + +static inline double msToDays(double ms) +{ + return floor(ms / msPerDay); +} + +static inline int msToYear(double ms) +{ + int approxYear = static_cast<int>(floor(ms / (msPerDay * 365.2425)) + 1970); + double msFromApproxYearTo1970 = msPerDay * daysFrom1970ToYear(approxYear); + if (msFromApproxYearTo1970 > ms) + return approxYear - 1; + if (msFromApproxYearTo1970 + msPerDay * daysInYear(approxYear) <= ms) + return approxYear + 1; + return approxYear; +} + +static inline int dayInYear(double ms, int year) +{ + return static_cast<int>(msToDays(ms) - daysFrom1970ToYear(year)); +} + +static inline double msToMilliseconds(double ms) +{ + double result = fmod(ms, msPerDay); + if (result < 0) + result += msPerDay; + return result; +} + +// 0: Sunday, 1: Monday, etc. +static inline int msToWeekDay(double ms) +{ + int wd = (static_cast<int>(msToDays(ms)) + 4) % 7; + if (wd < 0) + wd += 7; + return wd; +} + +static inline int msToSeconds(double ms) +{ + double result = fmod(floor(ms / msPerSecond), secondsPerMinute); + if (result < 0) + result += secondsPerMinute; + return static_cast<int>(result); +} + +static inline int msToMinutes(double ms) +{ + double result = fmod(floor(ms / msPerMinute), minutesPerHour); + if (result < 0) + result += minutesPerHour; + return static_cast<int>(result); +} + +static inline int msToHours(double ms) +{ + double result = fmod(floor(ms/msPerHour), hoursPerDay); + if (result < 0) + result += hoursPerDay; + return static_cast<int>(result); +} + +static inline int monthFromDayInYear(int dayInYear, bool leapYear) +{ + const int d = dayInYear; + int step; + + if (d < (step = 31)) + return 0; + step += (leapYear ? 29 : 28); + if (d < step) + return 1; + if (d < (step += 31)) + return 2; + if (d < (step += 30)) + return 3; + if (d < (step += 31)) + return 4; + if (d < (step += 30)) + return 5; + if (d < (step += 31)) + return 6; + if (d < (step += 31)) + return 7; + if (d < (step += 30)) + return 8; + if (d < (step += 31)) + return 9; + if (d < (step += 30)) + return 10; + return 11; +} + +static inline bool checkMonth(int dayInYear, int& startDayOfThisMonth, int& startDayOfNextMonth, int daysInThisMonth) +{ + startDayOfThisMonth = startDayOfNextMonth; + startDayOfNextMonth += daysInThisMonth; + return (dayInYear <= startDayOfNextMonth); +} + +static inline int dayInMonthFromDayInYear(int dayInYear, bool leapYear) +{ + const int d = dayInYear; + int step; + int next = 30; + + if (d <= next) + return d + 1; + const int daysInFeb = (leapYear ? 29 : 28); + if (checkMonth(d, step, next, daysInFeb)) + return d - step; + if (checkMonth(d, step, next, 31)) + return d - step; + if (checkMonth(d, step, next, 30)) + return d - step; + if (checkMonth(d, step, next, 31)) + return d - step; + if (checkMonth(d, step, next, 30)) + return d - step; + if (checkMonth(d, step, next, 31)) + return d - step; + if (checkMonth(d, step, next, 31)) + return d - step; + if (checkMonth(d, step, next, 30)) + return d - step; + if (checkMonth(d, step, next, 31)) + return d - step; + if (checkMonth(d, step, next, 30)) + return d - step; + step = next; + return d - step; +} + +static inline int monthToDayInYear(int month, bool isLeapYear) +{ + return firstDayOfMonth[isLeapYear][month]; +} + +static inline double timeToMS(double hour, double min, double sec, double ms) +{ + return (((hour * minutesPerHour + min) * secondsPerMinute + sec) * msPerSecond + ms); +} + +static int dateToDayInYear(int year, int month, int day) +{ + year += month / 12; + + month %= 12; + if (month < 0) { + month += 12; + --year; + } + + int yearday = static_cast<int>(floor(daysFrom1970ToYear(year))); + int monthday = monthToDayInYear(month, isLeapYear(year)); + + return yearday + monthday + day - 1; +} + +double getCurrentUTCTime() +{ + return floor(getCurrentUTCTimeWithMicroseconds()); +} + +#if PLATFORM(WIN_OS) + +static LARGE_INTEGER qpcFrequency; +static bool syncedTime; + +static double highResUpTime() +{ + // We use QPC, but only after sanity checking its result, due to bugs: + // http://support.microsoft.com/kb/274323 + // http://support.microsoft.com/kb/895980 + // http://msdn.microsoft.com/en-us/library/ms644904.aspx ("...you can get different results on different processors due to bugs in the basic input/output system (BIOS) or the hardware abstraction layer (HAL)." + + static LARGE_INTEGER qpcLast; + static DWORD tickCountLast; + static bool inited; + + LARGE_INTEGER qpc; + QueryPerformanceCounter(&qpc); + DWORD tickCount = GetTickCount(); + + if (inited) { + __int64 qpcElapsed = ((qpc.QuadPart - qpcLast.QuadPart) * 1000) / qpcFrequency.QuadPart; + __int64 tickCountElapsed; + if (tickCount >= tickCountLast) + tickCountElapsed = (tickCount - tickCountLast); + else { +#if COMPILER(MINGW) + __int64 tickCountLarge = tickCount + 0x100000000ULL; +#else + __int64 tickCountLarge = tickCount + 0x100000000I64; +#endif + tickCountElapsed = tickCountLarge - tickCountLast; + } + + // force a re-sync if QueryPerformanceCounter differs from GetTickCount by more than 500ms. + // (500ms value is from http://support.microsoft.com/kb/274323) + __int64 diff = tickCountElapsed - qpcElapsed; + if (diff > 500 || diff < -500) + syncedTime = false; + } else + inited = true; + + qpcLast = qpc; + tickCountLast = tickCount; + + return (1000.0 * qpc.QuadPart) / static_cast<double>(qpcFrequency.QuadPart);; +} + +static double lowResUTCTime() +{ + struct _timeb timebuffer; + _ftime(&timebuffer); + return timebuffer.time * msPerSecond + timebuffer.millitm; +} + +static bool qpcAvailable() +{ + static bool available; + static bool checked; + + if (checked) + return available; + + available = QueryPerformanceFrequency(&qpcFrequency); + checked = true; + return available; +} + +#endif + +double getCurrentUTCTimeWithMicroseconds() +{ +#if PLATFORM(WIN_OS) + // Use a combination of ftime and QueryPerformanceCounter. + // ftime returns the information we want, but doesn't have sufficient resolution. + // QueryPerformanceCounter has high resolution, but is only usable to measure time intervals. + // To combine them, we call ftime and QueryPerformanceCounter initially. Later calls will use QueryPerformanceCounter + // by itself, adding the delta to the saved ftime. We periodically re-sync to correct for drift. + static bool started; + static double syncLowResUTCTime; + static double syncHighResUpTime; + static double lastUTCTime; + + double lowResTime = lowResUTCTime(); + + if (!qpcAvailable()) + return lowResTime; + + double highResTime = highResUpTime(); + + if (!syncedTime) { + timeBeginPeriod(1); // increase time resolution around low-res time getter + syncLowResUTCTime = lowResTime = lowResUTCTime(); + timeEndPeriod(1); // restore time resolution + syncHighResUpTime = highResTime; + syncedTime = true; + } + + double highResElapsed = highResTime - syncHighResUpTime; + double utc = syncLowResUTCTime + highResElapsed; + + // force a clock re-sync if we've drifted + double lowResElapsed = lowResTime - syncLowResUTCTime; + const double maximumAllowedDriftMsec = 15.625 * 2.0; // 2x the typical low-res accuracy + if (fabs(highResElapsed - lowResElapsed) > maximumAllowedDriftMsec) + syncedTime = false; + + // make sure time doesn't run backwards (only correct if difference is < 2 seconds, since DST or clock changes could occur) + const double backwardTimeLimit = 2000.0; + if (utc < lastUTCTime && (lastUTCTime - utc) < backwardTimeLimit) + return lastUTCTime; + lastUTCTime = utc; +#else + struct timeval tv; + gettimeofday(&tv, 0); + double utc = tv.tv_sec * msPerSecond + tv.tv_usec / 1000.0; +#endif + return utc; +} + +void getLocalTime(const time_t* localTime, struct tm* localTM) +{ +#if COMPILER(MSVC7) || COMPILER(MINGW) + *localTM = *localtime(localTime); +#elif COMPILER(MSVC) + localtime_s(localTM, localTime); +#else + localtime_r(localTime, localTM); +#endif +} + +// There is a hard limit at 2038 that we currently do not have a workaround +// for (rdar://problem/5052975). +static inline int maximumYearForDST() +{ + return 2037; +} + +static inline int minimumYearForDST() +{ + // Because of the 2038 issue (see maximumYearForDST) if the current year is + // greater than the max year minus 27 (2010), we want to use the max year + // minus 27 instead, to ensure there is a range of 28 years that all years + // can map to. + return std::min(msToYear(getCurrentUTCTime()), maximumYearForDST() - 27) ; +} + +/* + * Find an equivalent year for the one given, where equivalence is deterined by + * the two years having the same leapness and the first day of the year, falling + * on the same day of the week. + * + * This function returns a year between this current year and 2037, however this + * function will potentially return incorrect results if the current year is after + * 2010, (rdar://problem/5052975), if the year passed in is before 1900 or after + * 2100, (rdar://problem/5055038). + */ +int equivalentYearForDST(int year) +{ + // It is ok if the cached year is not the current year as long as the rules + // for DST did not change between the two years; if they did the app would need + // to be restarted. + static int minYear = minimumYearForDST(); + int maxYear = maximumYearForDST(); + + int difference; + if (year > maxYear) + difference = minYear - year; + else if (year < minYear) + difference = maxYear - year; + else + return year; + + int quotient = difference / 28; + int product = (quotient) * 28; + + year += product; + ASSERT((year >= minYear && year <= maxYear) || (product - year == static_cast<int>(NaN))); + return year; +} + +static int32_t calculateUTCOffset() +{ + tm localt; + memset(&localt, 0, sizeof(localt)); + + // get the difference between this time zone and UTC on Jan 01, 2000 12:00:00 AM + localt.tm_mday = 1; + localt.tm_year = 100; + time_t utcOffset = 946684800 - mktime(&localt); + + return static_cast<int32_t>(utcOffset * 1000); +} + +#if PLATFORM(DARWIN) +static int32_t s_cachedUTCOffset; // In milliseconds. An assumption here is that access to an int32_t variable is atomic on platforms that take this code path. +static bool s_haveCachedUTCOffset; +static int s_notificationToken; +#endif + +/* + * Get the difference in milliseconds between this time zone and UTC (GMT) + * NOT including DST. + */ +double getUTCOffset() +{ +#if PLATFORM(DARWIN) + if (s_haveCachedUTCOffset) { + int notified; + uint32_t status = notify_check(s_notificationToken, ¬ified); + if (status == NOTIFY_STATUS_OK && !notified) + return s_cachedUTCOffset; + } +#endif + + int32_t utcOffset = calculateUTCOffset(); + +#if PLATFORM(DARWIN) + // Theoretically, it is possible that several threads will be executing this code at once, in which case we will have a race condition, + // and a newer value may be overwritten. In practice, time zones don't change that often. + s_cachedUTCOffset = utcOffset; +#endif + + return utcOffset; +} + +/* + * Get the DST offset for the time passed in. Takes + * seconds (not milliseconds) and cannot handle dates before 1970 + * on some OS' + */ +static double getDSTOffsetSimple(double localTimeSeconds, double utcOffset) +{ + if (localTimeSeconds > maxUnixTime) + localTimeSeconds = maxUnixTime; + else if (localTimeSeconds < 0) // Go ahead a day to make localtime work (does not work with 0) + localTimeSeconds += secondsPerDay; + + //input is UTC so we have to shift back to local time to determine DST thus the + getUTCOffset() + double offsetTime = (localTimeSeconds * msPerSecond) + utcOffset; + + // Offset from UTC but doesn't include DST obviously + int offsetHour = msToHours(offsetTime); + int offsetMinute = msToMinutes(offsetTime); + + // FIXME: time_t has a potential problem in 2038 + time_t localTime = static_cast<time_t>(localTimeSeconds); + + tm localTM; + getLocalTime(&localTime, &localTM); + + double diff = ((localTM.tm_hour - offsetHour) * secondsPerHour) + ((localTM.tm_min - offsetMinute) * 60); + + if (diff < 0) + diff += secondsPerDay; + + return (diff * msPerSecond); +} + +// Get the DST offset, given a time in UTC +static double getDSTOffset(double ms, double utcOffset) +{ + // On Mac OS X, the call to localtime (see getDSTOffsetSimple) will return historically accurate + // DST information (e.g. New Zealand did not have DST from 1946 to 1974) however the JavaScript + // standard explicitly dictates that historical information should not be considered when + // determining DST. For this reason we shift away from years that localtime can handle but would + // return historically accurate information. + int year = msToYear(ms); + int equivalentYear = equivalentYearForDST(year); + if (year != equivalentYear) { + bool leapYear = isLeapYear(year); + int dayInYearLocal = dayInYear(ms, year); + int dayInMonth = dayInMonthFromDayInYear(dayInYearLocal, leapYear); + int month = monthFromDayInYear(dayInYearLocal, leapYear); + int day = dateToDayInYear(equivalentYear, month, dayInMonth); + ms = (day * msPerDay) + msToMilliseconds(ms); + } + + return getDSTOffsetSimple(ms / msPerSecond, utcOffset); +} + +double gregorianDateTimeToMS(const GregorianDateTime& t, double milliSeconds, bool inputIsUTC) +{ + int day = dateToDayInYear(t.year + 1900, t.month, t.monthDay); + double ms = timeToMS(t.hour, t.minute, t.second, milliSeconds); + double result = (day * msPerDay) + ms; + + if (!inputIsUTC) { // convert to UTC + double utcOffset = getUTCOffset(); + result -= utcOffset; + result -= getDSTOffset(result, utcOffset); + } + + return result; +} + +void msToGregorianDateTime(double ms, bool outputIsUTC, GregorianDateTime& tm) +{ + // input is UTC + double dstOff = 0.0; + const double utcOff = getUTCOffset(); + + if (!outputIsUTC) { // convert to local time + dstOff = getDSTOffset(ms, utcOff); + ms += dstOff + utcOff; + } + + const int year = msToYear(ms); + tm.second = msToSeconds(ms); + tm.minute = msToMinutes(ms); + tm.hour = msToHours(ms); + tm.weekDay = msToWeekDay(ms); + tm.yearDay = dayInYear(ms, year); + tm.monthDay = dayInMonthFromDayInYear(tm.yearDay, isLeapYear(year)); + tm.month = monthFromDayInYear(tm.yearDay, isLeapYear(year)); + tm.year = year - 1900; + tm.isDST = dstOff != 0.0; + + tm.utcOffset = static_cast<long>((dstOff + utcOff) / msPerSecond); + tm.timeZone = NULL; +} + +void initDateMath() +{ +#ifndef NDEBUG + static bool alreadyInitialized; + ASSERT(!alreadyInitialized++); +#endif + + equivalentYearForDST(2000); // Need to call once to initialize a static used in this function. +#if PLATFORM(DARWIN) + // Register for a notification whenever the time zone changes. + uint32_t status = notify_register_check("com.apple.system.timezone", &s_notificationToken); + if (status == NOTIFY_STATUS_OK) { + s_cachedUTCOffset = calculateUTCOffset(); + s_haveCachedUTCOffset = true; + } +#endif +} + +static inline double ymdhmsToSeconds(long year, int mon, int day, int hour, int minute, int second) +{ + double days = (day - 32075) + + floor(1461 * (year + 4800.0 + (mon - 14) / 12) / 4) + + 367 * (mon - 2 - (mon - 14) / 12 * 12) / 12 + - floor(3 * ((year + 4900.0 + (mon - 14) / 12) / 100) / 4) + - 2440588; + return ((days * hoursPerDay + hour) * minutesPerHour + minute) * secondsPerMinute + second; +} + +// We follow the recommendation of RFC 2822 to consider all +// obsolete time zones not listed here equivalent to "-0000". +static const struct KnownZone { +#if !PLATFORM(WIN_OS) + const +#endif + char tzName[4]; + int tzOffset; +} known_zones[] = { + { "UT", 0 }, + { "GMT", 0 }, + { "EST", -300 }, + { "EDT", -240 }, + { "CST", -360 }, + { "CDT", -300 }, + { "MST", -420 }, + { "MDT", -360 }, + { "PST", -480 }, + { "PDT", -420 } +}; + +inline static void skipSpacesAndComments(const char*& s) +{ + int nesting = 0; + char ch; + while ((ch = *s)) { + if (!isASCIISpace(ch)) { + if (ch == '(') + nesting++; + else if (ch == ')' && nesting > 0) + nesting--; + else if (nesting == 0) + break; + } + s++; + } +} + +// returns 0-11 (Jan-Dec); -1 on failure +static int findMonth(const char* monthStr) +{ + ASSERT(monthStr); + char needle[4]; + for (int i = 0; i < 3; ++i) { + if (!*monthStr) + return -1; + needle[i] = static_cast<char>(toASCIILower(*monthStr++)); + } + needle[3] = '\0'; + const char *haystack = "janfebmaraprmayjunjulaugsepoctnovdec"; + const char *str = strstr(haystack, needle); + if (str) { + int position = static_cast<int>(str - haystack); + if (position % 3 == 0) + return position / 3; + } + return -1; +} + +double parseDate(const UString &date) +{ + // This parses a date in the form: + // Tuesday, 09-Nov-99 23:12:40 GMT + // or + // Sat, 01-Jan-2000 08:00:00 GMT + // or + // Sat, 01 Jan 2000 08:00:00 GMT + // or + // 01 Jan 99 22:00 +0100 (exceptions in rfc822/rfc2822) + // ### non RFC formats, added for Javascript: + // [Wednesday] January 09 1999 23:12:40 GMT + // [Wednesday] January 09 23:12:40 GMT 1999 + // + // We ignore the weekday. + + CString dateCString = date.UTF8String(); + const char *dateString = dateCString.c_str(); + + // Skip leading space + skipSpacesAndComments(dateString); + + long month = -1; + const char *wordStart = dateString; + // Check contents of first words if not number + while (*dateString && !isASCIIDigit(*dateString)) { + if (isASCIISpace(*dateString) || *dateString == '(') { + if (dateString - wordStart >= 3) + month = findMonth(wordStart); + skipSpacesAndComments(dateString); + wordStart = dateString; + } else + dateString++; + } + + // Missing delimiter between month and day (like "January29")? + if (month == -1 && wordStart != dateString) + month = findMonth(wordStart); + + skipSpacesAndComments(dateString); + + if (!*dateString) + return NaN; + + // ' 09-Nov-99 23:12:40 GMT' + char *newPosStr; + errno = 0; + long day = strtol(dateString, &newPosStr, 10); + if (errno) + return NaN; + dateString = newPosStr; + + if (!*dateString) + return NaN; + + if (day < 0) + return NaN; + + long year = 0; + if (day > 31) { + // ### where is the boundary and what happens below? + if (*dateString != '/') + return NaN; + // looks like a YYYY/MM/DD date + if (!*++dateString) + return NaN; + year = day; + month = strtol(dateString, &newPosStr, 10) - 1; + if (errno) + return NaN; + dateString = newPosStr; + if (*dateString++ != '/' || !*dateString) + return NaN; + day = strtol(dateString, &newPosStr, 10); + if (errno) + return NaN; + dateString = newPosStr; + } else if (*dateString == '/' && month == -1) { + dateString++; + // This looks like a MM/DD/YYYY date, not an RFC date. + month = day - 1; // 0-based + day = strtol(dateString, &newPosStr, 10); + if (errno) + return NaN; + if (day < 1 || day > 31) + return NaN; + dateString = newPosStr; + if (*dateString == '/') + dateString++; + if (!*dateString) + return NaN; + } else { + if (*dateString == '-') + dateString++; + + skipSpacesAndComments(dateString); + + if (*dateString == ',') + dateString++; + + if (month == -1) { // not found yet + month = findMonth(dateString); + if (month == -1) + return NaN; + + while (*dateString && *dateString != '-' && *dateString != ',' && !isASCIISpace(*dateString)) + dateString++; + + if (!*dateString) + return NaN; + + // '-99 23:12:40 GMT' + if (*dateString != '-' && *dateString != '/' && *dateString != ',' && !isASCIISpace(*dateString)) + return NaN; + dateString++; + } + } + + if (month < 0 || month > 11) + return NaN; + + // '99 23:12:40 GMT' + if (year <= 0 && *dateString) { + year = strtol(dateString, &newPosStr, 10); + if (errno) + return NaN; + } + + // Don't fail if the time is missing. + long hour = 0; + long minute = 0; + long second = 0; + if (!*newPosStr) + dateString = newPosStr; + else { + // ' 23:12:40 GMT' + if (!(isASCIISpace(*newPosStr) || *newPosStr == ',')) { + if (*newPosStr != ':') + return NaN; + // There was no year; the number was the hour. + year = -1; + } else { + // in the normal case (we parsed the year), advance to the next number + dateString = ++newPosStr; + skipSpacesAndComments(dateString); + } + + hour = strtol(dateString, &newPosStr, 10); + // Do not check for errno here since we want to continue + // even if errno was set becasue we are still looking + // for the timezone! + + // Read a number? If not, this might be a timezone name. + if (newPosStr != dateString) { + dateString = newPosStr; + + if (hour < 0 || hour > 23) + return NaN; + + if (!*dateString) + return NaN; + + // ':12:40 GMT' + if (*dateString++ != ':') + return NaN; + + minute = strtol(dateString, &newPosStr, 10); + if (errno) + return NaN; + dateString = newPosStr; + + if (minute < 0 || minute > 59) + return NaN; + + // ':40 GMT' + if (*dateString && *dateString != ':' && !isASCIISpace(*dateString)) + return NaN; + + // seconds are optional in rfc822 + rfc2822 + if (*dateString ==':') { + dateString++; + + second = strtol(dateString, &newPosStr, 10); + if (errno) + return NaN; + dateString = newPosStr; + + if (second < 0 || second > 59) + return NaN; + } + + skipSpacesAndComments(dateString); + + if (strncasecmp(dateString, "AM", 2) == 0) { + if (hour > 12) + return NaN; + if (hour == 12) + hour = 0; + dateString += 2; + skipSpacesAndComments(dateString); + } else if (strncasecmp(dateString, "PM", 2) == 0) { + if (hour > 12) + return NaN; + if (hour != 12) + hour += 12; + dateString += 2; + skipSpacesAndComments(dateString); + } + } + } + + bool haveTZ = false; + int offset = 0; + + // Don't fail if the time zone is missing. + // Some websites omit the time zone (4275206). + if (*dateString) { + if (strncasecmp(dateString, "GMT", 3) == 0 || strncasecmp(dateString, "UTC", 3) == 0) { + dateString += 3; + haveTZ = true; + } + + if (*dateString == '+' || *dateString == '-') { + long o = strtol(dateString, &newPosStr, 10); + if (errno) + return NaN; + dateString = newPosStr; + + if (o < -9959 || o > 9959) + return NaN; + + int sgn = (o < 0) ? -1 : 1; + o = abs(o); + if (*dateString != ':') { + offset = ((o / 100) * 60 + (o % 100)) * sgn; + } else { // GMT+05:00 + long o2 = strtol(dateString, &newPosStr, 10); + if (errno) + return NaN; + dateString = newPosStr; + offset = (o * 60 + o2) * sgn; + } + haveTZ = true; + } else { + for (int i = 0; i < int(sizeof(known_zones) / sizeof(KnownZone)); i++) { + if (0 == strncasecmp(dateString, known_zones[i].tzName, strlen(known_zones[i].tzName))) { + offset = known_zones[i].tzOffset; + dateString += strlen(known_zones[i].tzName); + haveTZ = true; + break; + } + } + } + } + + skipSpacesAndComments(dateString); + + if (*dateString && year == -1) { + year = strtol(dateString, &newPosStr, 10); + if (errno) + return NaN; + dateString = newPosStr; + } + + skipSpacesAndComments(dateString); + + // Trailing garbage + if (*dateString) + return NaN; + + // Y2K: Handle 2 digit years. + if (year >= 0 && year < 100) { + if (year < 50) + year += 2000; + else + year += 1900; + } + + // fall back to local timezone + if (!haveTZ) { + GregorianDateTime t; + t.monthDay = day; + t.month = month; + t.year = year - 1900; + t.isDST = -1; + t.second = second; + t.minute = minute; + t.hour = hour; + + // Use our gregorianDateTimeToMS() rather than mktime() as the latter can't handle the full year range. + return gregorianDateTimeToMS(t, 0, false); + } + + return (ymdhmsToSeconds(year, month + 1, day, hour, minute, second) - (offset * 60.0)) * msPerSecond; +} + +double timeClip(double t) +{ + if (!isfinite(t)) + return NaN; + if (fabs(t) > 8.64E15) + return NaN; + return trunc(t); +} + +UString formatDate(const GregorianDateTime &t) +{ + char buffer[100]; + snprintf(buffer, sizeof(buffer), "%s %s %02d %04d", + weekdayName[(t.weekDay + 6) % 7], + monthName[t.month], t.monthDay, t.year + 1900); + return buffer; +} + +UString formatDateUTCVariant(const GregorianDateTime &t) +{ + char buffer[100]; + snprintf(buffer, sizeof(buffer), "%s, %02d %s %04d", + weekdayName[(t.weekDay + 6) % 7], + t.monthDay, monthName[t.month], t.year + 1900); + return buffer; +} + +UString formatTime(const GregorianDateTime &t, bool utc) +{ + char buffer[100]; + if (utc) { + snprintf(buffer, sizeof(buffer), "%02d:%02d:%02d GMT", t.hour, t.minute, t.second); + } else { + int offset = abs(gmtoffset(t)); + char tzname[70]; + struct tm gtm = t; + strftime(tzname, sizeof(tzname), "%Z", >m); + + if (tzname[0]) { + snprintf(buffer, sizeof(buffer), "%02d:%02d:%02d GMT%c%02d%02d (%s)", + t.hour, t.minute, t.second, + gmtoffset(t) < 0 ? '-' : '+', offset / (60*60), (offset / 60) % 60, tzname); + } else { + snprintf(buffer, sizeof(buffer), "%02d:%02d:%02d GMT%c%02d%02d", + t.hour, t.minute, t.second, + gmtoffset(t) < 0 ? '-' : '+', offset / (60*60), (offset / 60) % 60); + } + } + return UString(buffer); +} + +} // namespace JSC |