clock: check for clock_gettime return value

clock_gettime() returns 0 for success, or -1 for failure.
Add missed checks for the return value.

Part of #5869

NO_DOC=refactoring
NO_TEST=refactoring
NO_CHANGELOG=refactoring

src/lib/core/clock.c

@@ -28,6 +28,7 @@
  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+#include "say.h"
 #include "clock.h"
 
 #include "trivia/util.h"
@@ -35,23 +36,31 @@ double
 clock_realtime(void)
 {
 	struct timespec ts;
-	clock_gettime(CLOCK_REALTIME, &ts);
+	int rc = clock_gettime(CLOCK_REALTIME, &ts);
+	if (rc != 0)
+		panic_syserror("clock_gettime failed");
 	return (double) ts.tv_sec + ts.tv_nsec / 1e9;
 
 }
+
 double
 clock_monotonic(void)
 {
 	struct timespec ts;
-	clock_gettime(CLOCK_MONOTONIC, &ts);
+	int rc = clock_gettime(CLOCK_MONOTONIC, &ts);
+	if (rc != 0)
+		panic_syserror("clock_gettime failed");
 	return (double) ts.tv_sec + ts.tv_nsec / 1e9;
 }
+
 double
 clock_process(void)
 {
 #if defined(CLOCK_PROCESS_CPUTIME_ID)
 	struct timespec ts;
-	clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
+	int rc = clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
+	if (rc != 0)
+		panic_syserror("clock_gettime failed");
 	return (double) ts.tv_sec + ts.tv_nsec / 1e9;
 #else
 	return (double) clock() / CLOCKS_PER_SEC;
@@ -63,7 +72,9 @@ clock_thread(void)
 {
 #if defined(CLOCK_THREAD_CPUTIME_ID)
 	struct timespec ts;
-	clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts);
+	int rc = clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts);
+	if (rc != 0)
+		panic_syserror("clock_gettime failed");
 	return (double) ts.tv_sec + ts.tv_nsec / 1e9;
 #else
 	return (double) clock() / CLOCKS_PER_SEC;
@@ -74,16 +85,19 @@ int64_t
 clock_realtime64(void)
 {
 	struct timespec ts;
-	clock_gettime(CLOCK_REALTIME, &ts);
+	int rc = clock_gettime(CLOCK_REALTIME, &ts);
+	if (rc != 0)
+		panic_syserror("clock_gettime failed");
 	return ((int64_t)ts.tv_sec) * 1000000000 + ts.tv_nsec;
-
 }
 
 int64_t
 clock_monotonic64(void)
 {
 	struct timespec ts;
-	clock_gettime(CLOCK_MONOTONIC, &ts);
+	int rc = clock_gettime(CLOCK_MONOTONIC, &ts);
+	if (rc != 0)
+		panic_syserror("clock_gettime failed");
 	return ((int64_t)ts.tv_sec) * 1000000000 + ts.tv_nsec;
 }
 
@@ -92,7 +106,9 @@ clock_process64(void)
 {
 #if defined(CLOCK_PROCESS_CPUTIME_ID)
 	struct timespec ts;
-	clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
+	int rc = clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
+	if (rc != 0)
+		panic_syserror("clock_gettime failed");
 	return ((int64_t)ts.tv_sec) * 1000000000 + ts.tv_nsec;
 #else
 	return (int64_t)clock() * 1000000000 / CLOCKS_PER_SEC;
@@ -104,7 +120,9 @@ clock_thread64(void)
 {
 #if defined(CLOCK_THREAD_CPUTIME_ID)
 	struct timespec ts;
-	clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts);
+	int rc = clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts);
+	if (rc != 0)
+		panic_syserror("clock_gettime failed");
 	return ((int64_t)ts.tv_sec) * 1000000000 + ts.tv_nsec;
 #else
 	return (int64_t)clock() * 1000000000 / CLOCKS_PER_SEC;