From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Sun, 28 Sep 2025 01:09:44 +0000 (+0900)
Subject: calendar-spec: use SAVE_TIMEZONE
X-Git-Tag: v259-rc1~399^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=672924356f9dc2876cc416a8e0cb25c1b6f1c0dd;p=thirdparty%2Fsystemd.git

calendar-spec: use SAVE_TIMEZONE

Then, we can avoid heavy fork() operation.
---

diff --git a/src/shared/calendarspec.c b/src/shared/calendarspec.c
index 3569f15db4f..b15f9290367 100644
--- a/src/shared/calendarspec.c
+++ b/src/shared/calendarspec.c
@@ -1426,13 +1426,7 @@ static int calendar_spec_next_usec_impl(const CalendarSpec *spec, usec_t usec, u
         return 0;
 }
 
-typedef struct SpecNextResult {
-        usec_t next;
-        int return_value;
-} SpecNextResult;
-
 int calendar_spec_next_usec(const CalendarSpec *spec, usec_t usec, usec_t *ret_next) {
-        SpecNextResult *shared, tmp;
         int r;
 
         assert(spec);
@@ -1440,39 +1434,16 @@ int calendar_spec_next_usec(const CalendarSpec *spec, usec_t usec, usec_t *ret_n
         if (isempty(spec->timezone))
                 return calendar_spec_next_usec_impl(spec, usec, ret_next);
 
-        shared = mmap(NULL, sizeof *shared, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, -1, 0);
-        if (shared == MAP_FAILED)
-                return negative_errno();
-
-        r = safe_fork("(sd-calendar)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_DEATHSIG_SIGKILL|FORK_WAIT, NULL);
-        if (r < 0) {
-                (void) munmap(shared, sizeof *shared);
-                return r;
-        }
-        if (r == 0) {
-                char *colon_tz;
+        SAVE_TIMEZONE;
 
-                /* tzset(3) says $TZ should be prefixed with ":" if we reference timezone files */
-                colon_tz = strjoina(":", spec->timezone);
+        /* tzset(3) says $TZ should be prefixed with ":" if we reference timezone files */
+        const char *colon_tz = strjoina(":", spec->timezone);
 
-                if (setenv("TZ", colon_tz, 1) != 0) {
-                        shared->return_value = negative_errno();
-                        _exit(EXIT_FAILURE);
-                }
-
-                tzset();
-
-                shared->return_value = calendar_spec_next_usec_impl(spec, usec, &shared->next);
-
-                _exit(EXIT_SUCCESS);
-        }
-
-        tmp = *shared;
-        if (munmap(shared, sizeof *shared) < 0)
-                return negative_errno();
+        r = RET_NERRNO(setenv("TZ", colon_tz, 1));
+        if (r < 0)
+                return r;
 
-        if (tmp.return_value == 0 && ret_next)
-                *ret_next = tmp.next;
+        tzset();
 
-        return tmp.return_value;
+        return calendar_spec_next_usec_impl(spec, usec, ret_next);
 }