syscalls: make nsleep handle unslept time correctly

JIRA: RTOS-977
phoenix-rtos · Nov 13, 2024 · 429a28f · 429a28f
1 parent dbbddd8
commit 429a28f
Showing 1 changed file with 10 additions and 5 deletions.
diff --git a/syscalls.c b/syscalls.c
@@ -330,7 +330,7 @@ int syscalls_nsleep(void *ustack)
 	process_t *proc = proc_current()->process;
 	time_t *sec;
 	long int *nsec;
-	time_t start, us, stop, diff;
+	time_t start, us, stop, elapsed, unslept;
 	int ret;
 
 	GETFROMSTACK(ustack, time_t *, sec, 0);
@@ -360,10 +360,15 @@ int syscalls_nsleep(void *ustack)
 
 	if (ret == -EINTR) {
 		proc_gettime(&stop, NULL);
-		diff = stop - start;
-		if (diff < us) {
-			*sec = diff / (1000 * 1000);
-			*nsec = (diff % (1000 * 1000)) * 1000;
+		elapsed = stop - start;
+		unslept = us - elapsed;
+		if ((long long)unslept <= 0) {
+			*sec = 0;
+			*nsec = 0;
+		}
+		else if (unslept < us) {
+			*sec = unslept / (1000 * 1000);
+			*nsec = (unslept % (1000 * 1000)) * 1000;
 		}
 	}