scc

commit e4678a7b0058662953bd640823b26606e710564c
parent d9de09f797e53933d3e77323311ec3a89f0b965b
Author: Roberto E. Vargas Caballero <k0ga@shike2.net>
Date:   Thu, 30 Apr 2026 11:56:35 +0200

libc/time: Optimize localtime()

When it is not a dst date we can avoid the additional call to gmtime()
because we already did a call with the correct offset.

Diffstat:
M
src/libc/time/localtime.c
 | 
9
+++++----

1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/src/libc/time/localtime.c b/src/libc/time/localtime.c
@@ -1,4 +1,3 @@
-#include <string.h>
 #include <time.h>
 
 #include "../libc.h"
@@ -15,18 +14,20 @@ localtime(const time_t *timep)
 
 	_tzset();
 	t = *timep - _timezone;
-	if (_isdst(gmtime(&t))) {
+	tm = gmtime(&t);
+
+	if (_isdst(tm)) {
 		dst = 1;
 		off = _dstzone;
 		name = _tzname[1];
+		t = *timep - off;
+		tm = gmtime(&t);
 	} else {
 		dst = 0;
 		off = _timezone;
 		name = _tzname[0];
 	}
 
-	t = *timep - off;
-	tm = gmtime(&t);
 	tm->tm_zone = name;
 	tm->tm_isdst = dst;
 	tm->tm_gmtoff = off;