Use monotonic clock to measure elapsed time.

The nanosleep regression test used gettimeofday(2).  Switch it to
a monotonic clock to avoid accidential fails from a call to
settimeofday(2) somewhere in the system.

from Christian Ludwig

diff --git a/regress/sys/kern/nanosleep/nanosleep.c b/regress/sys/kern/nanosleep/nanosleep.c
index 5ccc082..790707a 100644 (file)
--- a/regress/sys/kern/nanosleep/nanosleep.c
+++ b/regress/sys/kern/nanosleep/nanosleep.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: nanosleep.c,v 1.7 2018/05/22 18:33:41 cheloha Exp $   */
+/*     $OpenBSD: nanosleep.c,v 1.8 2024/02/29 18:17:41 bluhm Exp $     */
 /*
  *     Written by Artur Grabowski <art@openbsd.org> 2002 Public Domain.
  */
@@ -137,13 +137,13 @@ int
 time_elapsed(void)
 {
        struct timespec ts;
-       struct timeval stv, etv;
+       struct timespec stv, etv;
 
        ts.tv_sec = 0;
        ts.tv_nsec = 500000000;
 
-       if (gettimeofday(&stv, NULL) < 0) {
-               warn("gettimeofday");
+       if (clock_gettime(CLOCK_MONOTONIC, &stv) < 0) {
+               warn("clock_gettime");
                return 1;
        }
 
@@ -152,14 +152,14 @@ time_elapsed(void)
                return 1;
        }
 
-       if (gettimeofday(&etv, NULL) < 0) {
-               warn("gettimeofday");
+       if (clock_gettime(CLOCK_MONOTONIC, &etv) < 0) {
+               warn("clock_gettime");
                return 1;
        }
 
-       timersub(&etv, &stv, &stv);
+       timespecsub(&etv, &stv, &stv);
 
-       if (stv.tv_sec == 0 && stv.tv_usec < 500000) {
+       if (stv.tv_sec == 0 && stv.tv_nsec < 500000000) {
                warnx("slept less than 0.5 sec");
                return 1;
        }
@@ -171,7 +171,7 @@ int
 time_elapsed_with_signal(void)
 {
        struct timespec ts, rts;
-       struct timeval stv, etv;
+       struct timespec stv, etv;
        pid_t pid;
        int status;
 
@@ -195,8 +195,8 @@ time_elapsed_with_signal(void)
        rts.tv_sec = 0;
        rts.tv_nsec = 0;
 
-       if (gettimeofday(&stv, NULL) < 0) {
-               warn("gettimeofday");
+       if (clock_gettime(CLOCK_MONOTONIC, &stv) < 0) {
+               warn("clock_gettime");
                return 1;
        }
 
@@ -205,17 +205,17 @@ time_elapsed_with_signal(void)
                return 1;
        }
 
-       if (gettimeofday(&etv, NULL) < 0) {
-               warn("gettimeofday");
+       if (clock_gettime(CLOCK_MONOTONIC, &etv) < 0) {
+               warn("clock_gettime");
                return 1;
        }
 
-       timersub(&etv, &stv, &stv);
+       timespecsub(&etv, &stv, &stv);
 
        etv.tv_sec = rts.tv_sec;
-       etv.tv_usec = rts.tv_nsec / 1000 + 1; /* the '+ 1' is a "roundup" */
+       etv.tv_nsec = rts.tv_nsec;
 
-       timeradd(&etv, &stv, &stv);
+       timespecadd(&etv, &stv, &stv);
 
        if (stv.tv_sec < 10) {
                warnx("slept time + leftover time < 10 sec");