shithub: scc

Info  •  Files  •  Log  •  Branches

libc: Fix strftime (time.h)

%U, conversion specifier, stipulates the first day of week 01 be a Sunday.
%W, conversion specifier, stipulates the first day of week 01 be a Monday.

--- a/src/libc/time/strftime.c

+++ b/src/libc/time/strftime.c

@@ -17,6 +17,33 @@

 static char *am_pm[] = {"AM", "PM"};

+static int

+first(int day, int year)

+{

+	int ny;

+

+	ny = _newyear(year);

+	if (ny == day)

+		return 0;

+	return 7 - ny + day;

+}

+

+static int

+weeknum(struct tm* tm, int day)

+{

+	int fday, val;

+

+	fday = first(day, tm->tm_year);

+	if (tm->tm_yday < fday) {

+		val = 0;

+	} else {

+		val = tm->tm_yday - fday;

+		val /= 7;

+		val++;

+	}

+	return val;

+}

+

 static size_t

 sval(char *s, size_t siz, char **strs, int abrev, int idx, int max)

 {

@@ -210,14 +237,10 @@

 			val = tm->tm_wday+1;

 			goto number;

 		case 'U':

-			val = tm->tm_yday / 7;

-			if (_newyear(tm->tm_year) == SAT)

-				val++;

+			val = weeknum(tm, SUN);

 			goto number;

 		case 'W':

-			val = tm->tm_yday / 7;

-			if (_newyear(tm->tm_year) == MON)

-				val++;

+			val = weeknum(tm, MON);

 			goto number;

 		case 'w':

 			width = 1;