@@ -67,6 +67,48 @@ char* strptime(const char* s, const char* fmt, std::tm* tm) {
6767}
6868#endif
6969
70+ // Convert a cctz::weekday to a tm_wday value (0-6, Sunday = 0).
71+ int ToTmWday (weekday wd) {
72+ switch (wd) {
73+ case weekday::sunday:
74+ return 0 ;
75+ case weekday::monday:
76+ return 1 ;
77+ case weekday::tuesday:
78+ return 2 ;
79+ case weekday::wednesday:
80+ return 3 ;
81+ case weekday::thursday:
82+ return 4 ;
83+ case weekday::friday:
84+ return 5 ;
85+ case weekday::saturday:
86+ return 6 ;
87+ }
88+ return 0 ; /* NOTREACHED*/
89+ }
90+
91+ // Convert a tm_wday value (0-6, Sunday = 0) to a cctz::weekday.
92+ weekday FromTmWday (int tm_wday) {
93+ switch (tm_wday) {
94+ case 0 :
95+ return weekday::sunday;
96+ case 1 :
97+ return weekday::monday;
98+ case 2 :
99+ return weekday::tuesday;
100+ case 3 :
101+ return weekday::wednesday;
102+ case 4 :
103+ return weekday::thursday;
104+ case 5 :
105+ return weekday::friday;
106+ case 6 :
107+ return weekday::saturday;
108+ }
109+ return weekday::sunday; /* NOTREACHED*/
110+ }
111+
70112std::tm ToTM (const time_zone::absolute_lookup& al) {
71113 std::tm tm {};
72114 tm .tm_sec = al.cs .second ();
@@ -84,34 +126,19 @@ std::tm ToTM(const time_zone::absolute_lookup& al) {
84126 tm .tm_year = static_cast <int >(al.cs .year () - 1900 );
85127 }
86128
87- switch (get_weekday (al.cs )) {
88- case weekday::sunday:
89- tm .tm_wday = 0 ;
90- break ;
91- case weekday::monday:
92- tm .tm_wday = 1 ;
93- break ;
94- case weekday::tuesday:
95- tm .tm_wday = 2 ;
96- break ;
97- case weekday::wednesday:
98- tm .tm_wday = 3 ;
99- break ;
100- case weekday::thursday:
101- tm .tm_wday = 4 ;
102- break ;
103- case weekday::friday:
104- tm .tm_wday = 5 ;
105- break ;
106- case weekday::saturday:
107- tm .tm_wday = 6 ;
108- break ;
109- }
129+ tm .tm_wday = ToTmWday (get_weekday (al.cs ));
110130 tm .tm_yday = get_yearday (al.cs ) - 1 ;
111131 tm .tm_isdst = al.is_dst ? 1 : 0 ;
112132 return tm ;
113133}
114134
135+ // Returns the week of the year [0:53] given a civil day and the day on
136+ // which weeks are defined to start.
137+ int ToWeek (const civil_day& cd, weekday week_start) {
138+ const civil_day d (cd.year () % 400 , cd.month (), cd.day ());
139+ return static_cast <int >((d - prev_weekday (civil_year (d), week_start)) / 7 );
140+ }
141+
115142const char kDigits [] = " 0123456789"
116143
117144// Formats a 64-bit integer in the given field width. Note that it is up
@@ -355,7 +382,7 @@ std::string format(const std::string& format, const time_point<seconds>& tp,
355382 if (cur == end || (cur - percent) % 2 == 0 ) continue ;
356383
357384 // Simple specifiers that we handle ourselves.
358- if (strchr (" YmdeHMSzZs %"
385+ if (strchr (" YmdeUuWwHMSzZs %"
359386 if (cur - 1 != pending) {
360387 FormatTM (&result, std::string (pending, cur - 1 ), tm );
361388 }
@@ -376,6 +403,22 @@ std::string format(const std::string& format, const time_point<seconds>& tp,
376403 if (*cur == ' e' ' 0' ' ' // for Windows
377404 result.append (bp, static_cast <std::size_t >(ep - bp));
378405 break ;
406+ case ' U'
407+ bp = Format02d (ep, ToWeek (civil_day (al.cs ), weekday::sunday));
408+ result.append (bp, static_cast <std::size_t >(ep - bp));
409+ break ;
410+ case ' u'
411+ bp = Format64 (ep, 0 , tm .tm_wday ? tm .tm_wday : 7 );
412+ result.append (bp, static_cast <std::size_t >(ep - bp));
413+ break ;
414+ case ' W'
415+ bp = Format02d (ep, ToWeek (civil_day (al.cs ), weekday::monday));
416+ result.append (bp, static_cast <std::size_t >(ep - bp));
417+ break ;
418+ case ' w'
419+ bp = Format64 (ep, 0 , tm .tm_wday );
420+ result.append (bp, static_cast <std::size_t >(ep - bp));
421+ break ;
379422 case ' H'
380423 bp = Format02d (ep, al.cs .hour ());
381424 result.append (bp, static_cast <std::size_t >(ep - bp));
@@ -610,6 +653,17 @@ const char* ParseTM(const char* dp, const char* fmt, std::tm* tm) {
610653 return dp;
611654}
612655
656+ // Sets year, tm_mon and tm_mday given the year, week_num, and tm_wday,
657+ // and the day on which weeks are defined to start.
658+ void FromWeek (int week_num, weekday week_start, year_t * year, std::tm * tm ) {
659+ const civil_year y (*year % 400 );
660+ civil_day cd = prev_weekday (y, week_start); // week 0
661+ cd = next_weekday (cd - 1 , FromTmWday (tm ->tm_wday )) + (week_num * 7 );
662+ *year += cd.year () - y.year ();
663+ tm ->tm_mon = cd.month () - 1 ;
664+ tm ->tm_mday = cd.day ();
665+ }
666+
613667} // namespace
614668
615669// Uses strptime(3) to parse the given input. Supports the same extended
@@ -659,6 +713,8 @@ bool parse(const std::string& format, const std::string& input,
659713 const char * fmt = format.c_str (); // NUL terminated
660714 bool twelve_hour = false ;
661715 bool afternoon = false ;
716+ int week_num = -1 ;
717+ weekday week_start = weekday::sunday;
662718
663719 bool saw_percent_s = false ;
664720 std::int_fast64_t percent_s = 0 ;
@@ -697,10 +753,27 @@ bool parse(const std::string& format, const std::string& input,
697753 case ' m'
698754 data = ParseInt (data, 2 , 1 , 12 , &tm .tm_mon );
699755 if (data != nullptr ) tm .tm_mon -= 1 ;
756+ week_num = -1 ;
700757 continue ;
701758 case ' d'
702759 case ' e'
703760 data = ParseInt (data, 2 , 1 , 31 , &tm .tm_mday );
761+ week_num = -1 ;
762+ continue ;
763+ case ' U'
764+ data = ParseInt (data, 0 , 0 , 53 , &week_num);
765+ week_start = weekday::sunday;
766+ continue ;
767+ case ' W'
768+ data = ParseInt (data, 0 , 0 , 53 , &week_num);
769+ week_start = weekday::monday;
770+ continue ;
771+ case ' u'
772+ data = ParseInt (data, 0 , 1 , 7 , &tm .tm_wday );
773+ if (data != nullptr ) tm .tm_wday %= 7 ;
774+ continue ;
775+ case ' w'
776+ data = ParseInt (data, 0 , 0 , 6 , &tm .tm_wday );
704777 continue ;
705778 case ' H'
706779 data = ParseInt (data, 2 , 0 , 23 , &tm .tm_hour );
@@ -891,6 +964,9 @@ bool parse(const std::string& format, const std::string& input,
891964 year += 1900 ;
892965 }
893966
967+ // Compute year, tm.tm_mon and tm.tm_mday if we parsed a week number.
968+ if (week_num != -1 ) FromWeek (week_num, week_start, &year, &tm );
969+
894970 const int month = tm .tm_mon + 1 ;
895971 civil_second cs (year, month, tm .tm_mday , tm .tm_hour , tm .tm_min , tm .tm_sec );
896972
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