diff options
Diffstat (limited to 'time/strftime.c')
| -rw-r--r-- | time/strftime.c | 42 |
1 files changed, 30 insertions, 12 deletions
diff --git a/time/strftime.c b/time/strftime.c index 8c5e0cba9e..c781841c6a 100644 --- a/time/strftime.c +++ b/time/strftime.c @@ -75,7 +75,7 @@ Cambridge, MA 02139, USA. */ #endif #endif -static unsigned int week __P((const struct tm *const, int)); +static unsigned int week __P((const struct tm *const, int, int)); #define add(n, f) \ @@ -107,23 +107,37 @@ static unsigned int week __P((const struct tm *const, int)); inline #endif static unsigned int -week (tp, starting_day) +week (tp, starting_day, max_preceding) const struct tm *const tp; int starting_day; + int max_preceding; { - int wday, dl; + int wday, dl, base; wday = tp->tm_wday - starting_day; if (wday < 0) wday += 7; - /* Set DL to the day in the year of the last day of the week previous to the - one containing the day specified in TP. If DL is negative or zero, the - day specified in TP is in the first week of the year. Otherwise, - calculate the number of complete weeks before our week (DL / 7) and - add any partial week at the start of the year (DL % 7). */ + /* Set DL to the day in the year of the first day of the week + containing the day specified in TP. */ dl = tp->tm_yday - wday; - return dl <= 0 ? 0 : ((dl / 7) + ((dl % 7) == 0 ? 0 : 1)); + + /* For the computation following ISO 8601:1988 we set the number of + the week containing January 1st to 1 if this week has more than + MAX_PRECEDING days in the new year. For ISO 8601 this number is + 3, for the other representation it is 7 (i.e., not to be + fulfilled). */ + base = ((dl + 7) % 7) > max_preceding ? 1 : 0; + + /* If DL is negative we compute the result as 0 unless we have to + compute it according ISO 8601. In this case we have to return 53 + or 1 if the week containing January 1st has less than 4 days in + the new year or not. If DL is not negative we calculate the + number of complete weeks for our week (DL / 7) plus 1 (because + only for DL < 0 we are in week 0/53 and plus the number of the + first week computed in the last step. */ + return dl < 0 ? (dl < -max_preceding ? 53 : base) + : base + 1 + dl / 7; } #ifndef _NL_CURRENT @@ -175,8 +189,9 @@ strftime (s, maxsize, format, tp) #endif size_t wkday_len = strlen(f_wkday); size_t month_len = strlen(f_month); - const unsigned int y_week0 = week (tp, 0); - const unsigned int y_week1 = week (tp, 1); + const unsigned int y_week0 = week (tp, 0, 7); + const unsigned int y_week1 = week (tp, 1, 7); + const unsigned int y_week2 = week (tp, 1, 3); const char *zone; size_t zonelen; register size_t i = 0; @@ -340,7 +355,7 @@ strftime (s, maxsize, format, tp) #ifdef _LIBC add (maxdigits, printed = sprintf (p, number_fmt, number_value)); #else - add (sprintf (p, number_fmt, number_value); + add (maxdigits, sprintf (p, number_fmt, number_value); printed = strlen (p)); #endif @@ -405,6 +420,9 @@ strftime (s, maxsize, format, tp) case 'U': DO_NUMBER (2, y_week0); + case 'V': + DO_NUMBER (2, y_week2); + case 'W': DO_NUMBER (2, y_week1); |