diff options
Diffstat (limited to 'libc/unistd/sleep.c')
| -rw-r--r-- | libc/unistd/sleep.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/libc/unistd/sleep.c b/libc/unistd/sleep.c index 4381c45c7..c5c9cdd21 100644 --- a/libc/unistd/sleep.c +++ b/libc/unistd/sleep.c @@ -27,6 +27,9 @@ libc_hidden_proto(sleep) libc_hidden_proto(sigaction) libc_hidden_proto(sigprocmask) + +/* version perusing nanosleep */ +#if defined __UCLIBC_HAS_REALTIME__ //libc_hidden_proto(__sigaddset) //libc_hidden_proto(__sigemptyset) //libc_hidden_proto(__sigismember) @@ -114,4 +117,56 @@ unsigned int sleep (unsigned int seconds) return result; } #endif +#else /* __UCLIBC_HAS_REALTIME__ */ +libc_hidden_proto(sigaction) +/* no nanosleep, use signals and alarm() */ +static void sleep_alarm_handler(int attribute_unused sig) +{ +} +unsigned int sleep (unsigned int seconds) +{ + struct sigaction act, oact; + sigset_t set, oset; + unsigned int result, remaining; + time_t before, after; + int old_errno = errno; + + /* This is not necessary but some buggy programs depend on this. */ + if (seconds == 0) + return 0; + + /* block SIGALRM */ + if (__sigemptyset (&set) < 0 + || __sigaddset (&set, SIGALRM) < 0 + || sigprocmask (SIG_BLOCK, &set, &oset)) + return seconds; + + act.sa_handler = sleep_alarm_handler; + act.sa_flags = 0; + act.sa_mask = oset; + if (sigaction(SIGALRM, &act, &oact) < 0) + return seconds; + + before = time(NULL); + remaining = alarm(seconds); + if (remaining && remaining > seconds) { + /* restore user's alarm */ + (void) sigaction(SIGALRM, &oact, (struct sigaction *) NULL); + alarm(remaining); /* restore old alarm */ + sigsuspend(&oset); + after = time(NULL); + } else { + sigsuspend (&oset); + after = time(NULL); + (void) sigaction (SIGALRM, &oact, NULL); + } + result = after - before; + alarm(remaining > result ? remaining - result : 0); + sigprocmask (SIG_SETMASK, &oset, NULL); + + __set_errno(old_errno); + + return result > seconds ? 0 : seconds - result; +} +#endif /* __UCLIBC_HAS_REALTIME__ */ libc_hidden_def(sleep) |