diff options
author | Lennart Poettering <lennart@poettering.net> | 2018-05-29 12:55:33 +0200 |
---|---|---|
committer | Sven Eden <yamakuzure@gmx.net> | 2018-08-24 16:47:08 +0200 |
commit | e5743c1e0d822766cdd20756ec48ee781c6a2aee (patch) | |
tree | fddded280c70f0b2780bd112668249dde3d32a3a /src/basic | |
parent | eed5a7bdfdce83b00734d7d40fa29f271871acf7 (diff) |
time-util: introduce common implementation of TFD_TIMER_CANCEL_ON_SET client code
We now use pretty much the same code at three places, let's unify that.
Diffstat (limited to 'src/basic')
-rw-r--r-- | src/basic/time-util.c | 24 | ||||
-rw-r--r-- | src/basic/time-util.h | 2 |
2 files changed, 26 insertions, 0 deletions
diff --git a/src/basic/time-util.c b/src/basic/time-util.c index dc8db13c2..71d6179ef 100644 --- a/src/basic/time-util.c +++ b/src/basic/time-util.c @@ -1496,3 +1496,27 @@ bool in_utc_timezone(void) { return timezone == 0 && daylight == 0; } + +int time_change_fd(void) { + + /* We only care for the cancellation event, hence we set the timeout to the latest possible value. */ + static const struct itimerspec its = { + .it_value.tv_sec = TIME_T_MAX, + }; + + _cleanup_close_ int fd; + + assert_cc(sizeof(time_t) == sizeof(TIME_T_MAX)); + + /* Uses TFD_TIMER_CANCEL_ON_SET to get notifications whenever CLOCK_REALTIME makes a jump relative to + * CLOCK_MONOTONIC. */ + + fd = timerfd_create(CLOCK_REALTIME, TFD_NONBLOCK|TFD_CLOEXEC); + if (fd < 0) + return -errno; + + if (timerfd_settime(fd, TFD_TIMER_ABSTIME|TFD_TIMER_CANCEL_ON_SET, &its, NULL) < 0) + return -errno; + + return TAKE_FD(fd); +} diff --git a/src/basic/time-util.h b/src/basic/time-util.h index fec051109..94534794a 100644 --- a/src/basic/time-util.h +++ b/src/basic/time-util.h @@ -209,3 +209,5 @@ static inline usec_t usec_sub_signed(usec_t timestamp, int64_t delta) { #else #error "Yuck, time_t is neither 4 nor 8 bytes wide?" #endif + +int time_change_fd(void); |