alarm_milliseconds.c (1389B)
1 /* ISC license. */ 2 3 #include <skalibs/sysdeps.h> 4 #include <skalibs/alarm.h> 5 6 #ifdef SKALIBS_HASTIMER 7 8 #include <errno.h> 9 #include <signal.h> 10 #include <time.h> 11 #include "alarm-internal.h" 12 13 #undef MYCLOCK 14 #ifdef SKALIBS_HASCLOCKMON 15 # define MYCLOCK CLOCK_MONOTONIC 16 #else 17 # define MYCLOCK CLOCK_REALTIME 18 #endif 19 20 int alarm_milliseconds (unsigned int t) 21 { 22 struct itimerspec it = { .it_interval = { .tv_sec = 0, .tv_nsec = 0 }, .it_value = { .tv_sec = t / 1000, .tv_nsec = 1000000 * (t % 1000) } } ; 23 struct sigevent se = { .sigev_notify = SIGEV_SIGNAL, .sigev_signo = SIGALRM, .sigev_value = { .sival_int = 0 }, .sigev_notify_function = 0, .sigev_notify_attributes = 0 } ; 24 if (timer_create(MYCLOCK, &se, &timer_here) < 0) return 0 ; 25 if (timer_settime(timer_here, 0, &it, 0) < 0) 26 { 27 int e = errno ; 28 timer_delete(timer_here) ; 29 errno = e ; 30 return 0 ; 31 } 32 return 1 ; 33 } 34 35 #else 36 #ifdef SKALIBS_HASITIMER 37 38 #include <sys/time.h> 39 40 int alarm_milliseconds (unsigned int t) 41 { 42 struct itimerval it = { .it_interval = { .tv_sec = 0, .tv_usec = 0 }, .it_value = { .tv_sec = t / 1000, .tv_usec = 1000 * (t % 1000) } } ; 43 if (setitimer(ITIMER_REAL, &it, 0) < 0) return 0 ; 44 return 1 ; 45 } 46 47 #else 48 49 #include <unistd.h> 50 #include <limits.h> 51 52 int alarm_milliseconds (unsigned int t) 53 { 54 if (t > UINT_MAX - 999) return 0 ; 55 t = (t + 999) / 1000 ; 56 alarm(t) ; 57 return 1 ; 58 } 59 60 #endif 61 #endif