src/lib/libtime.js - external/github.com/emscripten-core/emscripten - Git at Google

 /**
  * @license
  * Copyright 2024 The Emscripten Authors
  * SPDX-License-Identifier: MIT
  */

 assert(!STANDALONE_WASM, "library_time.js should not be included in standalone mode");

 addToLibrary({
   _mktime_js__i53abi: true,
   _mktime_js__deps: ['$ydayFromDate'],
   _mktime_js: (tmPtr) => {
     var date = new Date({{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_year, 'i32') }}} + 1900,
                         {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'i32') }}},
                         {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'i32') }}},
                         {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'i32') }}},
                         {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_min, 'i32') }}},
                         {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'i32') }}},
                         0);

     // There's an ambiguous hour when the time goes back; the tm_isdst field is
     // used to disambiguate it.  Date() basically guesses, so we fix it up if it
     // guessed wrong, or fill in tm_isdst with the guess if it's -1.
     var dst = {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_isdst, 'i32') }}};
     var guessedOffset = date.getTimezoneOffset();
     var start = new Date(date.getFullYear(), 0, 1);
     var summerOffset = new Date(date.getFullYear(), 6, 1).getTimezoneOffset();
     var winterOffset = start.getTimezoneOffset();
     var dstOffset = Math.min(winterOffset, summerOffset); // DST is in December in South
     if (dst < 0) {
       // Attention: some regions don't have DST at all.
       {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_isdst, 'Number(summerOffset != winterOffset && dstOffset == guessedOffset)', 'i32') }}};
     } else if ((dst > 0) != (dstOffset == guessedOffset)) {
       var nonDstOffset = Math.max(winterOffset, summerOffset);
       var trueOffset = dst > 0 ? dstOffset : nonDstOffset;
       // Don't try setMinutes(date.getMinutes() + ...) -- it's messed up.
       date.setTime(date.getTime() + (trueOffset - guessedOffset)*60000);
     }

     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_wday, 'date.getDay()', 'i32') }}};
     var yday = ydayFromDate(date)|0;
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_yday, 'yday', 'i32') }}};
     // To match expected behavior, update fields from date
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'date.getSeconds()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_min, 'date.getMinutes()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'date.getHours()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'date.getDate()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'date.getMonth()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_year, 'date.getYear()', 'i32') }}};

     var timeMs = date.getTime();
     if (isNaN(timeMs)) {
       return -1;
     }
     // Return time in microseconds
     return timeMs / 1000;
   },

   _gmtime_js__i53abi: true,
   _gmtime_js: (time, tmPtr) => {
     var date = new Date(time * 1000);
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'date.getUTCSeconds()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_min, 'date.getUTCMinutes()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'date.getUTCHours()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'date.getUTCDate()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'date.getUTCMonth()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_year, 'date.getUTCFullYear()-1900', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_wday, 'date.getUTCDay()', 'i32') }}};
     var start = Date.UTC(date.getUTCFullYear(), 0, 1, 0, 0, 0, 0);
     var yday = ((date.getTime() - start) / (1000 * 60 * 60 * 24))|0;
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_yday, 'yday', 'i32') }}};
   },

   _timegm_js__i53abi: true,
   _timegm_js: (tmPtr) => {
     var time = Date.UTC({{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_year, 'i32') }}} + 1900,
                         {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'i32') }}},
                         {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'i32') }}},
                         {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'i32') }}},
                         {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_min, 'i32') }}},
                         {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'i32') }}},
                         0);
     var date = new Date(time);

     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_wday, 'date.getUTCDay()', 'i32') }}};
     var start = Date.UTC(date.getUTCFullYear(), 0, 1, 0, 0, 0, 0);
     var yday = ((date.getTime() - start) / (1000 * 60 * 60 * 24))|0;
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_yday, 'yday', 'i32') }}};

     return date.getTime() / 1000;
   },

   _localtime_js__i53abi: true,
   _localtime_js__deps: ['$ydayFromDate'],
   _localtime_js: (time, tmPtr) => {
     var date = new Date(time*1000);
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'date.getSeconds()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_min, 'date.getMinutes()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'date.getHours()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'date.getDate()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'date.getMonth()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_year, 'date.getFullYear()-1900', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_wday, 'date.getDay()', 'i32') }}};

     var yday = ydayFromDate(date)|0;
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_yday, 'yday', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_gmtoff, '-(date.getTimezoneOffset() * 60)', LONG_TYPE) }}};

     // Attention: DST is in December in South, and some regions don't have DST at all.
     var start = new Date(date.getFullYear(), 0, 1);
     var summerOffset = new Date(date.getFullYear(), 6, 1).getTimezoneOffset();
     var winterOffset = start.getTimezoneOffset();
     var dst = (summerOffset != winterOffset && date.getTimezoneOffset() == Math.min(winterOffset, summerOffset))|0;
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_isdst, 'dst', 'i32') }}};
   },

   // musl-internal function used to implement both `asctime` and `asctime_r`
   __asctime_r: (tmPtr, buf) => {
     var date = {
       tm_sec: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'i32') }}},
       tm_min: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_min, 'i32') }}},
       tm_hour: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'i32') }}},
       tm_mday: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'i32') }}},
       tm_mon: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'i32') }}},
       tm_year: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_year, 'i32') }}},
       tm_wday: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_wday, 'i32') }}}
     };
     var days = [ "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" ];
     var months = [ "Jan", "Feb", "Mar", "Apr", "May", "Jun",
                    "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" ];
     var s = days[date.tm_wday] + ' ' + months[date.tm_mon] +
         (date.tm_mday < 10 ? '  ' : ' ') + date.tm_mday +
         (date.tm_hour < 10 ? ' 0' : ' ') + date.tm_hour +
         (date.tm_min < 10 ? ':0' : ':') + date.tm_min +
         (date.tm_sec < 10 ? ':0' : ':') + date.tm_sec +
         ' ' + (1900 + date.tm_year) + "\n";

     // asctime_r is specced to behave in an undefined manner if the algorithm would attempt
     // to write out more than 26 bytes (including the null terminator).
     // See http://pubs.opengroup.org/onlinepubs/9699919799/functions/asctime.html
     // Our undefined behavior is to truncate the write to at most 26 bytes, including null terminator.
     stringToUTF8(s, buf, 26);
     return buf;
   },

   _tzset_js__deps: ['$stringToUTF8',
 #if ASSERTIONS
     '$lengthBytesUTF8',
 #endif
   ],
   _tzset_js__internal: true,
   _tzset_js: (timezone, daylight, std_name, dst_name) => {
     // TODO: Use (malleable) environment variables instead of system settings.
     var currentYear = new Date().getFullYear();
     var winter = new Date(currentYear, 0, 1);
     var summer = new Date(currentYear, 6, 1);
     var winterOffset = winter.getTimezoneOffset();
     var summerOffset = summer.getTimezoneOffset();

     // Local standard timezone offset. Local standard time is not adjusted for
     // daylight savings.  This code uses the fact that getTimezoneOffset returns
     // a greater value during Standard Time versus Daylight Saving Time (DST).
     // Thus it determines the expected output during Standard Time, and it
     // compares whether the output of the given date the same (Standard) or less
     // (DST).
     var stdTimezoneOffset = Math.max(winterOffset, summerOffset);

     // timezone is specified as seconds west of UTC ("The external variable
     // `timezone` shall be set to the difference, in seconds, between
     // Coordinated Universal Time (UTC) and local standard time."), the same
     // as returned by stdTimezoneOffset.
     // See http://pubs.opengroup.org/onlinepubs/009695399/functions/tzset.html
     {{{ makeSetValue('timezone', '0', 'stdTimezoneOffset * 60', '*') }}};

     {{{ makeSetValue('daylight', '0', 'Number(winterOffset != summerOffset)', 'i32') }}};

     var extractZone = (timezoneOffset) => {
       // Why inverse sign?
       // Read here https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getTimezoneOffset
       var sign = timezoneOffset >= 0 ? "-" : "+";

       var absOffset = Math.abs(timezoneOffset)
       var hours = String(Math.floor(absOffset / 60)).padStart(2, "0");
       var minutes = String(absOffset % 60).padStart(2, "0");

       return `UTC${sign}${hours}${minutes}`;
     }

     var winterName = extractZone(winterOffset);
     var summerName = extractZone(summerOffset);
 #if ASSERTIONS
     assert(winterName);
     assert(summerName);
     assert(lengthBytesUTF8(winterName) <= {{{ cDefs.TZNAME_MAX }}}, `timezone name truncated to fit in TZNAME_MAX (${winterName})`);
     assert(lengthBytesUTF8(summerName) <= {{{ cDefs.TZNAME_MAX }}}, `timezone name truncated to fit in TZNAME_MAX (${summerName})`);
 #endif
     if (summerOffset < winterOffset) {
       // Northern hemisphere
       stringToUTF8(winterName, std_name, {{{ cDefs.TZNAME_MAX + 1 }}});
       stringToUTF8(summerName, dst_name, {{{ cDefs.TZNAME_MAX + 1 }}});
     } else {
       stringToUTF8(winterName, dst_name, {{{ cDefs.TZNAME_MAX + 1 }}});
       stringToUTF8(summerName, std_name, {{{ cDefs.TZNAME_MAX + 1 }}});
     }
   },

   $MONTH_DAYS_REGULAR: [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31],
   $MONTH_DAYS_LEAP: [31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31],
   $MONTH_DAYS_REGULAR_CUMULATIVE: [0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334],
   $MONTH_DAYS_LEAP_CUMULATIVE: [0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335],

   $isLeapYear: (year) => year%4 === 0 && (year%100 !== 0 || year%400 === 0),

   $ydayFromDate__deps: ['$isLeapYear', '$MONTH_DAYS_LEAP_CUMULATIVE', '$MONTH_DAYS_REGULAR_CUMULATIVE'],
   $ydayFromDate: (date) => {
     var leap = isLeapYear(date.getFullYear());
     var monthDaysCumulative = (leap ? MONTH_DAYS_LEAP_CUMULATIVE : MONTH_DAYS_REGULAR_CUMULATIVE);
     var yday = monthDaysCumulative[date.getMonth()] + date.getDate() - 1; // -1 since it's days since Jan 1

     return yday;
   },

   $arraySum: (array, index) => {
     var sum = 0;
     for (var i = 0; i <= index; sum += array[i++]) {
       // no-op
     }
     return sum;
   },

   $addDays__deps: ['$isLeapYear', '$MONTH_DAYS_LEAP', '$MONTH_DAYS_REGULAR'],
   $addDays: (date, days) => {
     var newDate = new Date(date.getTime());
     while (days > 0) {
       var leap = isLeapYear(newDate.getFullYear());
       var currentMonth = newDate.getMonth();
       var daysInCurrentMonth = (leap ? MONTH_DAYS_LEAP : MONTH_DAYS_REGULAR)[currentMonth];

       if (days > daysInCurrentMonth-newDate.getDate()) {
         // we spill over to next month
         days -= (daysInCurrentMonth-newDate.getDate()+1);
         newDate.setDate(1);
         if (currentMonth < 11) {
           newDate.setMonth(currentMonth+1)
         } else {
           newDate.setMonth(0);
           newDate.setFullYear(newDate.getFullYear()+1);
         }
       } else {
         // we stay in current month
         newDate.setDate(newDate.getDate()+days);
         return newDate;
       }
     }

     return newDate;
   },

   strptime__deps: ['$isLeapYear', '$arraySum', '$addDays', '$MONTH_DAYS_REGULAR', '$MONTH_DAYS_LEAP',
                    '$lengthBytesUTF8'],
   strptime: (buf, format, tm) => {
     // char *strptime(const char *restrict buf, const char *restrict format, struct tm *restrict tm);
     // http://pubs.opengroup.org/onlinepubs/009695399/functions/strptime.html
     var pattern = UTF8ToString(format);

     // escape special characters
     // TODO: not sure we really need to escape all of these in JS regexps
     var SPECIAL_CHARS = '\\!@#$^&*()+=-[]/{}|:<>?,.';
     for (var i=0, ii=SPECIAL_CHARS.length; i<ii; ++i) {
       pattern = pattern.replace(new RegExp('\\'+SPECIAL_CHARS[i], 'g'), '\\'+SPECIAL_CHARS[i]);
     }

     // reduce number of matchers
     var EQUIVALENT_MATCHERS = {
       'A':  '%a',
       'B':  '%b',
       'c':  '%a %b %d %H:%M:%S %Y',
       'D':  '%m\\/%d\\/%y',
       'e':  '%d',
       'F':  '%Y-%m-%d',
       'h':  '%b',
       'R':  '%H\\:%M',
       'r':  '%I\\:%M\\:%S\\s%p',
       'T':  '%H\\:%M\\:%S',
       'x':  '%m\\/%d\\/(?:%y|%Y)',
       'X':  '%H\\:%M\\:%S'
     };
     // TODO: take care of locale

     var DATE_PATTERNS = {
       /* weekday name */    'a': '(?:Sun(?:day)?)|(?:Mon(?:day)?)|(?:Tue(?:sday)?)|(?:Wed(?:nesday)?)|(?:Thu(?:rsday)?)|(?:Fri(?:day)?)|(?:Sat(?:urday)?)',
       /* month name */      'b': '(?:Jan(?:uary)?)|(?:Feb(?:ruary)?)|(?:Mar(?:ch)?)|(?:Apr(?:il)?)|May|(?:Jun(?:e)?)|(?:Jul(?:y)?)|(?:Aug(?:ust)?)|(?:Sep(?:tember)?)|(?:Oct(?:ober)?)|(?:Nov(?:ember)?)|(?:Dec(?:ember)?)',
       /* century */         'C': '\\d\\d',
       /* day of month */    'd': '0[1-9]|[1-9](?!\\d)|1\\d|2\\d|30|31',
       /* hour (24hr) */     'H': '\\d(?!\\d)|[0,1]\\d|20|21|22|23',
       /* hour (12hr) */     'I': '\\d(?!\\d)|0\\d|10|11|12',
       /* day of year */     'j': '00[1-9]|0?[1-9](?!\\d)|0?[1-9]\\d(?!\\d)|[1,2]\\d\\d|3[0-6]\\d',
       /* month */           'm': '0[1-9]|[1-9](?!\\d)|10|11|12',
       /* minutes */         'M': '0\\d|\\d(?!\\d)|[1-5]\\d',
       /* whitespace */      'n': ' ',
       /* AM/PM */           'p': 'AM|am|PM|pm|A\\.M\\.|a\\.m\\.|P\\.M\\.|p\\.m\\.',
       /* seconds */         'S': '0\\d|\\d(?!\\d)|[1-5]\\d|60',
       /* week number */     'U': '0\\d|\\d(?!\\d)|[1-4]\\d|50|51|52|53',
       /* week number */     'W': '0\\d|\\d(?!\\d)|[1-4]\\d|50|51|52|53',
       /* weekday number */  'w': '[0-6]',
       /* 2-digit year */    'y': '\\d\\d',
       /* 4-digit year */    'Y': '\\d\\d\\d\\d',
       /* whitespace */      't': ' ',
       /* time zone */       'z': 'Z|(?:[\\+\\-]\\d\\d:?(?:\\d\\d)?)'
     };

     var MONTH_NUMBERS = {JAN: 0, FEB: 1, MAR: 2, APR: 3, MAY: 4, JUN: 5, JUL: 6, AUG: 7, SEP: 8, OCT: 9, NOV: 10, DEC: 11};
     var DAY_NUMBERS_SUN_FIRST = {SUN: 0, MON: 1, TUE: 2, WED: 3, THU: 4, FRI: 5, SAT: 6};
     var DAY_NUMBERS_MON_FIRST = {MON: 0, TUE: 1, WED: 2, THU: 3, FRI: 4, SAT: 5, SUN: 6};

     var capture = [];
     var pattern_out = pattern
       .replace(/%(.)/g, (m, c) => EQUIVALENT_MATCHERS[c] || m)
       .replace(/%(.)/g, (_, c) => {
         let pat = DATE_PATTERNS[c];
         if (pat){
           capture.push(c);
           return `(${pat})`;
         } else {
           return c;
         }
       })
       .replace( // any number of space or tab characters match zero or more spaces
         /\s+/g,'\\s*'
       );

     var matches = new RegExp('^'+pattern_out, "i").exec(UTF8ToString(buf))

     function initDate() {
       function fixup(value, min, max) {
         return (typeof value != 'number' || isNaN(value)) ? min : (value>=min ? (value<=max ? value: max): min);
       };
       return {
         year: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_year, 'i32') }}} + 1900 , 1970, 9999),
         month: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_mon, 'i32') }}}, 0, 11),
         day: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_mday, 'i32') }}}, 1, 31),
         hour: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_hour, 'i32') }}}, 0, 23),
         min: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_min, 'i32') }}}, 0, 59),
         sec: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_sec, 'i32') }}}, 0, 59),
         gmtoff: 0
       };
     };

     if (matches) {
       var date = initDate();
       var value;

       var getMatch = (symbol) => {
         var pos = capture.indexOf(symbol);
         // check if symbol appears in regexp
         if (pos >= 0) {
           // return matched value or null (falsy!) for non-matches
           return matches[pos+1];
         }
         return;
       };

       // seconds
       if ((value=getMatch('S'))) {
         date.sec = Number(value);
       }

       // minutes
       if ((value=getMatch('M'))) {
         date.min = Number(value);
       }

       // hours
       if ((value=getMatch('H'))) {
         // 24h clock
         date.hour = Number(value);
       } else if ((value = getMatch('I'))) {
         // AM/PM clock
         var hour = Number(value);
         if ((value=getMatch('p'))) {
           hour += value.toUpperCase()[0] === 'P' ? 12 : 0;
         }
         date.hour = hour;
       }

       // year
       if ((value=getMatch('Y'))) {
         // parse from four-digit year
         date.year = Number(value);
       } else if ((value=getMatch('y'))) {
         // parse from two-digit year...
         var year = Number(value);
         if ((value=getMatch('C'))) {
           // ...and century
           year += Number(value)*100;
         } else {
           // ...and rule-of-thumb
           year += year<69 ? 2000 : 1900;
         }
         date.year = year;
       }

       // month
       if ((value=getMatch('m'))) {
         // parse from month number
         date.month = Number(value)-1;
       } else if ((value=getMatch('b'))) {
         // parse from month name
         date.month = MONTH_NUMBERS[value.substring(0,3).toUpperCase()] || 0;
         // TODO: derive month from day in year+year, week number+day of week+year
       }

       // day
       if ((value=getMatch('d'))) {
         // get day of month directly
         date.day = Number(value);
       } else if ((value=getMatch('j'))) {
         // get day of month from day of year ...
         var day = Number(value);
         var leapYear = isLeapYear(date.year);
         for (var month=0; month<12; ++month) {
           var daysUntilMonth = arraySum(leapYear ? MONTH_DAYS_LEAP : MONTH_DAYS_REGULAR, month-1);
           if (day<=daysUntilMonth+(leapYear ? MONTH_DAYS_LEAP : MONTH_DAYS_REGULAR)[month]) {
             date.day = day-daysUntilMonth;
           }
         }
       } else if ((value=getMatch('a'))) {
         // get day of month from weekday ...
         var weekDay = value.substring(0,3).toUpperCase();
         if ((value=getMatch('U'))) {
           // ... and week number (Sunday being first day of week)
           // Week number of the year (Sunday as the first day of the week) as a decimal number [00,53].
           // All days in a new year preceding the first Sunday are considered to be in week 0.
           var weekDayNumber = DAY_NUMBERS_SUN_FIRST[weekDay];
           var weekNumber = Number(value);

           // January 1st
           var janFirst = new Date(date.year, 0, 1);
           var endDate;
           if (janFirst.getDay() === 0) {
             // Jan 1st is a Sunday, and, hence in the 1st CW
             endDate = addDays(janFirst, weekDayNumber+7*(weekNumber-1));
           } else {
             // Jan 1st is not a Sunday, and, hence still in the 0th CW
             endDate = addDays(janFirst, 7-janFirst.getDay()+weekDayNumber+7*(weekNumber-1));
           }
           date.day = endDate.getDate();
           date.month = endDate.getMonth();
         } else if ((value=getMatch('W'))) {
           // ... and week number (Monday being first day of week)
           // Week number of the year (Monday as the first day of the week) as a decimal number [00,53].
           // All days in a new year preceding the first Monday are considered to be in week 0.
           var weekDayNumber = DAY_NUMBERS_MON_FIRST[weekDay];
           var weekNumber = Number(value);

           // January 1st
           var janFirst = new Date(date.year, 0, 1);
           var endDate;
           if (janFirst.getDay()===1) {
             // Jan 1st is a Monday, and, hence in the 1st CW
              endDate = addDays(janFirst, weekDayNumber+7*(weekNumber-1));
           } else {
             // Jan 1st is not a Monday, and, hence still in the 0th CW
             endDate = addDays(janFirst, 7-janFirst.getDay()+1+weekDayNumber+7*(weekNumber-1));
           }

           date.day = endDate.getDate();
           date.month = endDate.getMonth();
         }
       }

       // time zone
       if ((value = getMatch('z'))) {
         // GMT offset as either 'Z' or +-HH:MM or +-HH or +-HHMM
         if (value.toLowerCase() === 'z'){
           date.gmtoff = 0;
         } else {
           var match = value.match(/^((?:\-|\+)\d\d):?(\d\d)?/);
           date.gmtoff = match[1] * 3600;
           if (match[2]) {
             date.gmtoff += date.gmtoff >0 ? match[2] * 60 : -match[2] * 60
           }
         }
       }

       /*
       tm_sec  int seconds after the minute  0-61*
       tm_min  int minutes after the hour  0-59
       tm_hour int hours since midnight  0-23
       tm_mday int day of the month  1-31
       tm_mon  int months since January  0-11
       tm_year int years since 1900
       tm_wday int days since Sunday 0-6
       tm_yday int days since January 1  0-365
       tm_isdst  int Daylight Saving Time flag
       tm_gmtoff long offset from GMT (seconds)
       */

       var fullDate = new Date(date.year, date.month, date.day, date.hour, date.min, date.sec, 0);
       {{{ makeSetValue('tm', C_STRUCTS.tm.tm_sec, 'fullDate.getSeconds()', 'i32') }}};
       {{{ makeSetValue('tm', C_STRUCTS.tm.tm_min, 'fullDate.getMinutes()', 'i32') }}};
       {{{ makeSetValue('tm', C_STRUCTS.tm.tm_hour, 'fullDate.getHours()', 'i32') }}};
       {{{ makeSetValue('tm', C_STRUCTS.tm.tm_mday, 'fullDate.getDate()', 'i32') }}};
       {{{ makeSetValue('tm', C_STRUCTS.tm.tm_mon, 'fullDate.getMonth()', 'i32') }}};
       {{{ makeSetValue('tm', C_STRUCTS.tm.tm_year, 'fullDate.getFullYear()-1900', 'i32') }}};
       {{{ makeSetValue('tm', C_STRUCTS.tm.tm_wday, 'fullDate.getDay()', 'i32') }}};
       {{{ makeSetValue('tm', C_STRUCTS.tm.tm_yday, 'arraySum(isLeapYear(fullDate.getFullYear()) ? MONTH_DAYS_LEAP : MONTH_DAYS_REGULAR, fullDate.getMonth()-1)+fullDate.getDate()-1', 'i32') }}};
       {{{ makeSetValue('tm', C_STRUCTS.tm.tm_isdst, '0', 'i32') }}};
       {{{ makeSetValue('tm', C_STRUCTS.tm.tm_gmtoff, 'date.gmtoff', LONG_TYPE) }}};

       // we need to convert the matched sequence into an integer array to take care of UTF-8 characters > 0x7F
       // TODO: not sure that intArrayFromString handles all unicode characters correctly
       return buf+lengthBytesUTF8(matches[0]);
     }

     return 0;
   },
   strptime_l__deps: ['strptime'],
   strptime_l: (buf, format, tm, locale) => _strptime(buf, format, tm), // no locale support yet
 });
	/**
	* @license
	* Copyright 2024 The Emscripten Authors
	* SPDX-License-Identifier: MIT
	*/

	assert(!STANDALONE_WASM, "library_time.js should not be included in standalone mode");

	addToLibrary({
	_mktime_js__i53abi: true,
	_mktime_js__deps: ['$ydayFromDate'],
	_mktime_js: (tmPtr) => {
	var date = new Date({{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_year, 'i32') }}} + 1900,
	{{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'i32') }}},
	{{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'i32') }}},
	{{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'i32') }}},
	{{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_min, 'i32') }}},
	{{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'i32') }}},
	0);

	// There's an ambiguous hour when the time goes back; the tm_isdst field is
	// used to disambiguate it. Date() basically guesses, so we fix it up if it
	// guessed wrong, or fill in tm_isdst with the guess if it's -1.
	var dst = {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_isdst, 'i32') }}};
	var guessedOffset = date.getTimezoneOffset();
	var start = new Date(date.getFullYear(), 0, 1);
	var summerOffset = new Date(date.getFullYear(), 6, 1).getTimezoneOffset();
	var winterOffset = start.getTimezoneOffset();
	var dstOffset = Math.min(winterOffset, summerOffset); // DST is in December in South
	if (dst < 0) {
	// Attention: some regions don't have DST at all.
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_isdst, 'Number(summerOffset != winterOffset && dstOffset == guessedOffset)', 'i32') }}};
	} else if ((dst > 0) != (dstOffset == guessedOffset)) {
	var nonDstOffset = Math.max(winterOffset, summerOffset);
	var trueOffset = dst > 0 ? dstOffset : nonDstOffset;
	// Don't try setMinutes(date.getMinutes() + ...) -- it's messed up.
	date.setTime(date.getTime() + (trueOffset - guessedOffset)*60000);
	}

	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_wday, 'date.getDay()', 'i32') }}};
	var yday = ydayFromDate(date)\|0;
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_yday, 'yday', 'i32') }}};
	// To match expected behavior, update fields from date
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'date.getSeconds()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_min, 'date.getMinutes()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'date.getHours()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'date.getDate()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'date.getMonth()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_year, 'date.getYear()', 'i32') }}};

	var timeMs = date.getTime();
	if (isNaN(timeMs)) {
	return -1;
	}
	// Return time in microseconds
	return timeMs / 1000;
	},

	_gmtime_js__i53abi: true,
	_gmtime_js: (time, tmPtr) => {
	var date = new Date(time * 1000);
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'date.getUTCSeconds()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_min, 'date.getUTCMinutes()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'date.getUTCHours()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'date.getUTCDate()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'date.getUTCMonth()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_year, 'date.getUTCFullYear()-1900', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_wday, 'date.getUTCDay()', 'i32') }}};
	var start = Date.UTC(date.getUTCFullYear(), 0, 1, 0, 0, 0, 0);
	var yday = ((date.getTime() - start) / (1000 * 60 * 60 * 24))\|0;
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_yday, 'yday', 'i32') }}};
	},

	_timegm_js__i53abi: true,
	_timegm_js: (tmPtr) => {
	var time = Date.UTC({{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_year, 'i32') }}} + 1900,
	{{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'i32') }}},
	{{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'i32') }}},
	{{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'i32') }}},
	{{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_min, 'i32') }}},
	{{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'i32') }}},
	0);
	var date = new Date(time);

	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_wday, 'date.getUTCDay()', 'i32') }}};
	var start = Date.UTC(date.getUTCFullYear(), 0, 1, 0, 0, 0, 0);
	var yday = ((date.getTime() - start) / (1000 * 60 * 60 * 24))\|0;
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_yday, 'yday', 'i32') }}};

	return date.getTime() / 1000;
	},

	_localtime_js__i53abi: true,
	_localtime_js__deps: ['$ydayFromDate'],
	_localtime_js: (time, tmPtr) => {
	var date = new Date(time*1000);
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'date.getSeconds()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_min, 'date.getMinutes()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'date.getHours()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'date.getDate()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'date.getMonth()', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_year, 'date.getFullYear()-1900', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_wday, 'date.getDay()', 'i32') }}};

	var yday = ydayFromDate(date)\|0;
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_yday, 'yday', 'i32') }}};
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_gmtoff, '-(date.getTimezoneOffset() * 60)', LONG_TYPE) }}};

	// Attention: DST is in December in South, and some regions don't have DST at all.
	var start = new Date(date.getFullYear(), 0, 1);
	var summerOffset = new Date(date.getFullYear(), 6, 1).getTimezoneOffset();
	var winterOffset = start.getTimezoneOffset();
	var dst = (summerOffset != winterOffset && date.getTimezoneOffset() == Math.min(winterOffset, summerOffset))\|0;
	{{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_isdst, 'dst', 'i32') }}};
	},

	// musl-internal function used to implement both `asctime` and `asctime_r`
	__asctime_r: (tmPtr, buf) => {
	var date = {
	tm_sec: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'i32') }}},
	tm_min: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_min, 'i32') }}},
	tm_hour: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'i32') }}},
	tm_mday: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mday, 'i32') }}},
	tm_mon: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_mon, 'i32') }}},
	tm_year: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_year, 'i32') }}},
	tm_wday: {{{ makeGetValue('tmPtr', C_STRUCTS.tm.tm_wday, 'i32') }}}
	};
	var days = [ "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" ];
	var months = [ "Jan", "Feb", "Mar", "Apr", "May", "Jun",
	"Jul", "Aug", "Sep", "Oct", "Nov", "Dec" ];
	var s = days[date.tm_wday] + ' ' + months[date.tm_mon] +
	(date.tm_mday < 10 ? ' ' : ' ') + date.tm_mday +
	(date.tm_hour < 10 ? ' 0' : ' ') + date.tm_hour +
	(date.tm_min < 10 ? ':0' : ':') + date.tm_min +
	(date.tm_sec < 10 ? ':0' : ':') + date.tm_sec +
	' ' + (1900 + date.tm_year) + "\n";

	// asctime_r is specced to behave in an undefined manner if the algorithm would attempt
	// to write out more than 26 bytes (including the null terminator).
	// See http://pubs.opengroup.org/onlinepubs/9699919799/functions/asctime.html
	// Our undefined behavior is to truncate the write to at most 26 bytes, including null terminator.
	stringToUTF8(s, buf, 26);
	return buf;
	},

	_tzset_js__deps: ['$stringToUTF8',
	#if ASSERTIONS
	'$lengthBytesUTF8',
	#endif
	],
	_tzset_js__internal: true,
	_tzset_js: (timezone, daylight, std_name, dst_name) => {
	// TODO: Use (malleable) environment variables instead of system settings.
	var currentYear = new Date().getFullYear();
	var winter = new Date(currentYear, 0, 1);
	var summer = new Date(currentYear, 6, 1);
	var winterOffset = winter.getTimezoneOffset();
	var summerOffset = summer.getTimezoneOffset();

	// Local standard timezone offset. Local standard time is not adjusted for
	// daylight savings. This code uses the fact that getTimezoneOffset returns
	// a greater value during Standard Time versus Daylight Saving Time (DST).
	// Thus it determines the expected output during Standard Time, and it
	// compares whether the output of the given date the same (Standard) or less
	// (DST).
	var stdTimezoneOffset = Math.max(winterOffset, summerOffset);

	// timezone is specified as seconds west of UTC ("The external variable
	// `timezone` shall be set to the difference, in seconds, between
	// Coordinated Universal Time (UTC) and local standard time."), the same
	// as returned by stdTimezoneOffset.
	// See http://pubs.opengroup.org/onlinepubs/009695399/functions/tzset.html
	{{{ makeSetValue('timezone', '0', 'stdTimezoneOffset * 60', '*') }}};

	{{{ makeSetValue('daylight', '0', 'Number(winterOffset != summerOffset)', 'i32') }}};

	var extractZone = (timezoneOffset) => {
	// Why inverse sign?
	// Read here https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getTimezoneOffset
	var sign = timezoneOffset >= 0 ? "-" : "+";

	var absOffset = Math.abs(timezoneOffset)
	var hours = String(Math.floor(absOffset / 60)).padStart(2, "0");
	var minutes = String(absOffset % 60).padStart(2, "0");

	return `UTC${sign}${hours}${minutes}`;
	}

	var winterName = extractZone(winterOffset);
	var summerName = extractZone(summerOffset);
	#if ASSERTIONS
	assert(winterName);
	assert(summerName);
	assert(lengthBytesUTF8(winterName) <= {{{ cDefs.TZNAME_MAX }}}, `timezone name truncated to fit in TZNAME_MAX (${winterName})`);
	assert(lengthBytesUTF8(summerName) <= {{{ cDefs.TZNAME_MAX }}}, `timezone name truncated to fit in TZNAME_MAX (${summerName})`);
	#endif
	if (summerOffset < winterOffset) {
	// Northern hemisphere
	stringToUTF8(winterName, std_name, {{{ cDefs.TZNAME_MAX + 1 }}});
	stringToUTF8(summerName, dst_name, {{{ cDefs.TZNAME_MAX + 1 }}});
	} else {
	stringToUTF8(winterName, dst_name, {{{ cDefs.TZNAME_MAX + 1 }}});
	stringToUTF8(summerName, std_name, {{{ cDefs.TZNAME_MAX + 1 }}});
	}
	},

	$MONTH_DAYS_REGULAR: [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31],
	$MONTH_DAYS_LEAP: [31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31],
	$MONTH_DAYS_REGULAR_CUMULATIVE: [0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334],
	$MONTH_DAYS_LEAP_CUMULATIVE: [0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335],

	$isLeapYear: (year) => year%4 === 0 && (year%100 !== 0 \|\| year%400 === 0),

	$ydayFromDate__deps: ['$isLeapYear', '$MONTH_DAYS_LEAP_CUMULATIVE', '$MONTH_DAYS_REGULAR_CUMULATIVE'],
	$ydayFromDate: (date) => {
	var leap = isLeapYear(date.getFullYear());
	var monthDaysCumulative = (leap ? MONTH_DAYS_LEAP_CUMULATIVE : MONTH_DAYS_REGULAR_CUMULATIVE);
	var yday = monthDaysCumulative[date.getMonth()] + date.getDate() - 1; // -1 since it's days since Jan 1

	return yday;
	},

	$arraySum: (array, index) => {
	var sum = 0;
	for (var i = 0; i <= index; sum += array[i++]) {
	// no-op
	}
	return sum;
	},

	$addDays__deps: ['$isLeapYear', '$MONTH_DAYS_LEAP', '$MONTH_DAYS_REGULAR'],
	$addDays: (date, days) => {
	var newDate = new Date(date.getTime());
	while (days > 0) {
	var leap = isLeapYear(newDate.getFullYear());
	var currentMonth = newDate.getMonth();
	var daysInCurrentMonth = (leap ? MONTH_DAYS_LEAP : MONTH_DAYS_REGULAR)[currentMonth];

	if (days > daysInCurrentMonth-newDate.getDate()) {
	// we spill over to next month
	days -= (daysInCurrentMonth-newDate.getDate()+1);
	newDate.setDate(1);
	if (currentMonth < 11) {
	newDate.setMonth(currentMonth+1)
	} else {
	newDate.setMonth(0);
	newDate.setFullYear(newDate.getFullYear()+1);
	}
	} else {
	// we stay in current month
	newDate.setDate(newDate.getDate()+days);
	return newDate;
	}
	}

	return newDate;
	},

	strptime__deps: ['$isLeapYear', '$arraySum', '$addDays', '$MONTH_DAYS_REGULAR', '$MONTH_DAYS_LEAP',
	'$lengthBytesUTF8'],
	strptime: (buf, format, tm) => {
	// char strptime(const char restrict buf, const char restrict format, struct tm restrict tm);
	// http://pubs.opengroup.org/onlinepubs/009695399/functions/strptime.html
	var pattern = UTF8ToString(format);

	// escape special characters
	// TODO: not sure we really need to escape all of these in JS regexps
	var SPECIAL_CHARS = '\\!@#$^&*()+=-[]/{}\|:<>?,.';
	for (var i=0, ii=SPECIAL_CHARS.length; i<ii; ++i) {
	pattern = pattern.replace(new RegExp('\\'+SPECIAL_CHARS[i], 'g'), '\\'+SPECIAL_CHARS[i]);
	}

	// reduce number of matchers
	var EQUIVALENT_MATCHERS = {
	'A': '%a',
	'B': '%b',
	'c': '%a %b %d %H:%M:%S %Y',
	'D': '%m\\/%d\\/%y',
	'e': '%d',
	'F': '%Y-%m-%d',
	'h': '%b',
	'R': '%H\\:%M',
	'r': '%I\\:%M\\:%S\\s%p',
	'T': '%H\\:%M\\:%S',
	'x': '%m\\/%d\\/(?:%y\|%Y)',
	'X': '%H\\:%M\\:%S'
	};
	// TODO: take care of locale

	var DATE_PATTERNS = {
	/* weekday name */ 'a': '(?:Sun(?:day)?)\|(?:Mon(?:day)?)\|(?:Tue(?:sday)?)\|(?:Wed(?:nesday)?)\|(?:Thu(?:rsday)?)\|(?:Fri(?:day)?)\|(?:Sat(?:urday)?)',
	/* month name */ 'b': '(?:Jan(?:uary)?)\|(?:Feb(?:ruary)?)\|(?:Mar(?:ch)?)\|(?:Apr(?:il)?)\|May\|(?:Jun(?:e)?)\|(?:Jul(?:y)?)\|(?:Aug(?:ust)?)\|(?:Sep(?:tember)?)\|(?:Oct(?:ober)?)\|(?:Nov(?:ember)?)\|(?:Dec(?:ember)?)',
	/* century */ 'C': '\\d\\d',
	/* day of month */ 'd': '0[1-9]\|[1-9](?!\\d)\|1\\d\|2\\d\|30\|31',
	/* hour (24hr) */ 'H': '\\d(?!\\d)\|[0,1]\\d\|20\|21\|22\|23',
	/* hour (12hr) */ 'I': '\\d(?!\\d)\|0\\d\|10\|11\|12',
	/* day of year */ 'j': '00[1-9]\|0?[1-9](?!\\d)\|0?[1-9]\\d(?!\\d)\|[1,2]\\d\\d\|3[0-6]\\d',
	/* month */ 'm': '0[1-9]\|[1-9](?!\\d)\|10\|11\|12',
	/* minutes */ 'M': '0\\d\|\\d(?!\\d)\|[1-5]\\d',
	/* whitespace */ 'n': ' ',
	/* AM/PM */ 'p': 'AM\|am\|PM\|pm\|A\\.M\\.\|a\\.m\\.\|P\\.M\\.\|p\\.m\\.',
	/* seconds */ 'S': '0\\d\|\\d(?!\\d)\|[1-5]\\d\|60',
	/* week number */ 'U': '0\\d\|\\d(?!\\d)\|[1-4]\\d\|50\|51\|52\|53',
	/* week number */ 'W': '0\\d\|\\d(?!\\d)\|[1-4]\\d\|50\|51\|52\|53',
	/* weekday number */ 'w': '[0-6]',
	/* 2-digit year */ 'y': '\\d\\d',
	/* 4-digit year */ 'Y': '\\d\\d\\d\\d',
	/* whitespace */ 't': ' ',
	/* time zone */ 'z': 'Z\|(?:[\\+\\-]\\d\\d:?(?:\\d\\d)?)'
	};

	var MONTH_NUMBERS = {JAN: 0, FEB: 1, MAR: 2, APR: 3, MAY: 4, JUN: 5, JUL: 6, AUG: 7, SEP: 8, OCT: 9, NOV: 10, DEC: 11};
	var DAY_NUMBERS_SUN_FIRST = {SUN: 0, MON: 1, TUE: 2, WED: 3, THU: 4, FRI: 5, SAT: 6};
	var DAY_NUMBERS_MON_FIRST = {MON: 0, TUE: 1, WED: 2, THU: 3, FRI: 4, SAT: 5, SUN: 6};

	var capture = [];
	var pattern_out = pattern
	.replace(/%(.)/g, (m, c) => EQUIVALENT_MATCHERS[c] \|\| m)
	.replace(/%(.)/g, (_, c) => {
	let pat = DATE_PATTERNS[c];
	if (pat){
	capture.push(c);
	return `(${pat})`;
	} else {
	return c;
	}
	})
	.replace( // any number of space or tab characters match zero or more spaces
	/\s+/g,'\\s*'
	);

	var matches = new RegExp('^'+pattern_out, "i").exec(UTF8ToString(buf))

	function initDate() {
	function fixup(value, min, max) {
	return (typeof value != 'number' \|\| isNaN(value)) ? min : (value>=min ? (value<=max ? value: max): min);
	};
	return {
	year: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_year, 'i32') }}} + 1900 , 1970, 9999),
	month: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_mon, 'i32') }}}, 0, 11),
	day: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_mday, 'i32') }}}, 1, 31),
	hour: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_hour, 'i32') }}}, 0, 23),
	min: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_min, 'i32') }}}, 0, 59),
	sec: fixup({{{ makeGetValue('tm', C_STRUCTS.tm.tm_sec, 'i32') }}}, 0, 59),
	gmtoff: 0
	};
	};

	if (matches) {
	var date = initDate();
	var value;

	var getMatch = (symbol) => {
	var pos = capture.indexOf(symbol);
	// check if symbol appears in regexp
	if (pos >= 0) {
	// return matched value or null (falsy!) for non-matches
	return matches[pos+1];
	}
	return;
	};

	// seconds
	if ((value=getMatch('S'))) {
	date.sec = Number(value);
	}

	// minutes
	if ((value=getMatch('M'))) {
	date.min = Number(value);
	}

	// hours
	if ((value=getMatch('H'))) {
	// 24h clock
	date.hour = Number(value);
	} else if ((value = getMatch('I'))) {
	// AM/PM clock
	var hour = Number(value);
	if ((value=getMatch('p'))) {
	hour += value.toUpperCase()[0] === 'P' ? 12 : 0;
	}
	date.hour = hour;
	}

	// year
	if ((value=getMatch('Y'))) {
	// parse from four-digit year
	date.year = Number(value);
	} else if ((value=getMatch('y'))) {
	// parse from two-digit year...
	var year = Number(value);
	if ((value=getMatch('C'))) {
	// ...and century
	year += Number(value)*100;
	} else {
	// ...and rule-of-thumb
	year += year<69 ? 2000 : 1900;
	}
	date.year = year;
	}

	// month
	if ((value=getMatch('m'))) {
	// parse from month number
	date.month = Number(value)-1;
	} else if ((value=getMatch('b'))) {
	// parse from month name
	date.month = MONTH_NUMBERS[value.substring(0,3).toUpperCase()] \|\| 0;
	// TODO: derive month from day in year+year, week number+day of week+year
	}

	// day
	if ((value=getMatch('d'))) {
	// get day of month directly
	date.day = Number(value);
	} else if ((value=getMatch('j'))) {
	// get day of month from day of year ...
	var day = Number(value);
	var leapYear = isLeapYear(date.year);
	for (var month=0; month<12; ++month) {
	var daysUntilMonth = arraySum(leapYear ? MONTH_DAYS_LEAP : MONTH_DAYS_REGULAR, month-1);
	if (day<=daysUntilMonth+(leapYear ? MONTH_DAYS_LEAP : MONTH_DAYS_REGULAR)[month]) {
	date.day = day-daysUntilMonth;
	}
	}
	} else if ((value=getMatch('a'))) {
	// get day of month from weekday ...
	var weekDay = value.substring(0,3).toUpperCase();
	if ((value=getMatch('U'))) {
	// ... and week number (Sunday being first day of week)
	// Week number of the year (Sunday as the first day of the week) as a decimal number [00,53].
	// All days in a new year preceding the first Sunday are considered to be in week 0.
	var weekDayNumber = DAY_NUMBERS_SUN_FIRST[weekDay];
	var weekNumber = Number(value);

	// January 1st
	var janFirst = new Date(date.year, 0, 1);
	var endDate;
	if (janFirst.getDay() === 0) {
	// Jan 1st is a Sunday, and, hence in the 1st CW
	endDate = addDays(janFirst, weekDayNumber+7*(weekNumber-1));
	} else {
	// Jan 1st is not a Sunday, and, hence still in the 0th CW
	endDate = addDays(janFirst, 7-janFirst.getDay()+weekDayNumber+7*(weekNumber-1));
	}
	date.day = endDate.getDate();
	date.month = endDate.getMonth();
	} else if ((value=getMatch('W'))) {
	// ... and week number (Monday being first day of week)
	// Week number of the year (Monday as the first day of the week) as a decimal number [00,53].
	// All days in a new year preceding the first Monday are considered to be in week 0.
	var weekDayNumber = DAY_NUMBERS_MON_FIRST[weekDay];
	var weekNumber = Number(value);

	// January 1st
	var janFirst = new Date(date.year, 0, 1);
	var endDate;
	if (janFirst.getDay()===1) {
	// Jan 1st is a Monday, and, hence in the 1st CW
	endDate = addDays(janFirst, weekDayNumber+7*(weekNumber-1));
	} else {
	// Jan 1st is not a Monday, and, hence still in the 0th CW
	endDate = addDays(janFirst, 7-janFirst.getDay()+1+weekDayNumber+7*(weekNumber-1));
	}

	date.day = endDate.getDate();
	date.month = endDate.getMonth();
	}
	}

	// time zone
	if ((value = getMatch('z'))) {
	// GMT offset as either 'Z' or +-HH:MM or +-HH or +-HHMM
	if (value.toLowerCase() === 'z'){
	date.gmtoff = 0;
	} else {
	var match = value.match(/^((?:\-\|\+)\d\d):?(\d\d)?/);
	date.gmtoff = match[1] * 3600;
	if (match[2]) {
	date.gmtoff += date.gmtoff >0 ? match[2] * 60 : -match[2] * 60
	}
	}
	}

	/*
	tm_sec int seconds after the minute 0-61*
	tm_min int minutes after the hour 0-59
	tm_hour int hours since midnight 0-23
	tm_mday int day of the month 1-31
	tm_mon int months since January 0-11
	tm_year int years since 1900
	tm_wday int days since Sunday 0-6
	tm_yday int days since January 1 0-365
	tm_isdst int Daylight Saving Time flag
	tm_gmtoff long offset from GMT (seconds)
	*/

	var fullDate = new Date(date.year, date.month, date.day, date.hour, date.min, date.sec, 0);
	{{{ makeSetValue('tm', C_STRUCTS.tm.tm_sec, 'fullDate.getSeconds()', 'i32') }}};
	{{{ makeSetValue('tm', C_STRUCTS.tm.tm_min, 'fullDate.getMinutes()', 'i32') }}};
	{{{ makeSetValue('tm', C_STRUCTS.tm.tm_hour, 'fullDate.getHours()', 'i32') }}};
	{{{ makeSetValue('tm', C_STRUCTS.tm.tm_mday, 'fullDate.getDate()', 'i32') }}};
	{{{ makeSetValue('tm', C_STRUCTS.tm.tm_mon, 'fullDate.getMonth()', 'i32') }}};
	{{{ makeSetValue('tm', C_STRUCTS.tm.tm_year, 'fullDate.getFullYear()-1900', 'i32') }}};
	{{{ makeSetValue('tm', C_STRUCTS.tm.tm_wday, 'fullDate.getDay()', 'i32') }}};
	{{{ makeSetValue('tm', C_STRUCTS.tm.tm_yday, 'arraySum(isLeapYear(fullDate.getFullYear()) ? MONTH_DAYS_LEAP : MONTH_DAYS_REGULAR, fullDate.getMonth()-1)+fullDate.getDate()-1', 'i32') }}};
	{{{ makeSetValue('tm', C_STRUCTS.tm.tm_isdst, '0', 'i32') }}};
	{{{ makeSetValue('tm', C_STRUCTS.tm.tm_gmtoff, 'date.gmtoff', LONG_TYPE) }}};

	// we need to convert the matched sequence into an integer array to take care of UTF-8 characters > 0x7F
	// TODO: not sure that intArrayFromString handles all unicode characters correctly
	return buf+lengthBytesUTF8(matches[0]);
	}

	return 0;
	},
	strptime_l__deps: ['strptime'],
	strptime_l: (buf, format, tm, locale) => _strptime(buf, format, tm), // no locale support yet
	});