Also add some tests.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 tools/include/nolibc/time.h                  | 34 ++++++++++++++++++++++++++++
 tools/testing/selftests/nolibc/nolibc-test.c |  1 +
 2 files changed, 35 insertions(+)

diff --git a/tools/include/nolibc/time.h b/tools/include/nolibc/time.h
index fc387940d51f389d4233bd5712588dced31ae6e5..d02bc44d2643a5e39afa808841f7175bfab5ff7e 100644
--- a/tools/include/nolibc/time.h
+++ b/tools/include/nolibc/time.h
@@ -36,6 +36,8 @@ void __nolibc_timespec_kernel_to_user(const struct __kernel_timespec *kts, struc
  * int clock_getres(clockid_t clockid, struct timespec *res);
  * int clock_gettime(clockid_t clockid, struct timespec *tp);
  * int clock_settime(clockid_t clockid, const struct timespec *tp);
+ * int clock_nanosleep(clockid_t clockid, int flags, const struct timespec *rqtp,
+ *                     struct timespec *rmtp)
  */
 
 static __attribute__((unused))
@@ -107,6 +109,32 @@ int clock_settime(clockid_t clockid, struct timespec *tp)
 	return __sysret(sys_clock_settime(clockid, tp));
 }
 
+static __attribute__((unused))
+int sys_clock_nanosleep(clockid_t clockid, int flags, const struct timespec *rqtp,
+			struct timespec *rmtp)
+{
+#if defined(__NR_clock_nanosleep)
+	return my_syscall4(__NR_clock_nanosleep, clockid, flags, rqtp, rmtp);
+#elif defined(__NR_clock_nanosleep_time64)
+	struct __kernel_timespec krqtp, krmtp;
+	int ret;
+
+	__nolibc_timespec_user_to_kernel(rqtp, &krqtp);
+	ret = my_syscall4(__NR_clock_nanosleep_time64, clockid, flags, &krqtp, &krmtp);
+	if (rmtp)
+		__nolibc_timespec_kernel_to_user(&krmtp, rmtp);
+	return ret;
+#else
+	return __nolibc_enosys(__func__, clockid, flags, rqtp, rmtp);
+#endif
+}
+
+static __attribute__((unused))
+int clock_nanosleep(clockid_t clockid, int flags, const struct timespec *rqtp,
+		    struct timespec *rmtp)
+{
+	return __sysret(sys_clock_nanosleep(clockid, flags, rqtp, rmtp));
+}
 
 static __inline__
 double difftime(time_t time1, time_t time2)
@@ -114,6 +142,12 @@ double difftime(time_t time1, time_t time2)
 	return time1 - time2;
 }
 
+static __inline__
+int nanosleep(const struct timespec *rqtp, struct timespec *rmtp)
+{
+	return clock_nanosleep(CLOCK_REALTIME, 0, rqtp, rmtp);
+}
+
 
 static __attribute__((unused))
 time_t time(time_t *tptr)
diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index b5bca1dcf36e95a576ca9ffba4f7c213978a3f35..315229233930265501296dfeb9bc2838bb6fef84 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -1363,6 +1363,7 @@ int run_syscall(int min, int max)
 		CASE_TEST(mmap_bad);          EXPECT_PTRER(1, mmap(NULL, 0, PROT_READ, MAP_PRIVATE, 0, 0), MAP_FAILED, EINVAL); break;
 		CASE_TEST(munmap_bad);        EXPECT_SYSER(1, munmap(NULL, 0), -1, EINVAL); break;
 		CASE_TEST(mmap_munmap_good);  EXPECT_SYSZR(1, test_mmap_munmap()); break;
+		CASE_TEST(nanosleep);         ts.tv_nsec = -1; EXPECT_SYSER(1, nanosleep(&ts, NULL), -1, EINVAL); break;
 		CASE_TEST(open_tty);          EXPECT_SYSNE(1, tmp = open("/dev/null", O_RDONLY), -1); if (tmp != -1) close(tmp); break;
 		CASE_TEST(open_blah);         EXPECT_SYSER(1, tmp = open("/proc/self/blah", O_RDONLY), -1, ENOENT); if (tmp != -1) close(tmp); break;
 		CASE_TEST(openat_dir);        EXPECT_SYSZR(1, test_openat()); break;

---
base-commit: 1536aa0fb1e09cb50f401ec4852c60f38173d751
change-id: 20250704-nolibc-nanosleep-2476b806b0d5

Best regards,
-- 
Thomas Weißschuh <thomas.weissschuh@linutronix.de>

Hi Thomas,

On Fri, Jul 04, 2025 at 04:19:48PM +0200, Thomas Weißschuh wrote:
> +static __attribute__((unused))
> +int sys_clock_nanosleep(clockid_t clockid, int flags, const struct timespec *rqtp,
> +			struct timespec *rmtp)
> +{
> +#if defined(__NR_clock_nanosleep)
> +	return my_syscall4(__NR_clock_nanosleep, clockid, flags, rqtp, rmtp);
> +#elif defined(__NR_clock_nanosleep_time64)
> +	struct __kernel_timespec krqtp, krmtp;
> +	int ret;
> +
> +	__nolibc_timespec_user_to_kernel(rqtp, &krqtp);
> +	ret = my_syscall4(__NR_clock_nanosleep_time64, clockid, flags, &krqtp, &krmtp);
> +	if (rmtp)
> +		__nolibc_timespec_kernel_to_user(&krmtp, rmtp);
> +	return ret;
> +#else
> +	return __nolibc_enosys(__func__, clockid, flags, rqtp, rmtp);
> +#endif

I don't know which archs do not have clock_nanosleep, but if it becomes
needed on some of them, we could probably fall back to pslelect() if
available, of course, and ignore the clockid.

Acked-by: Willy Tarreau <w@1wt.eu>

Cheers,
Willy

On 2025-07-06 08:26:33+0200, Willy Tarreau wrote:
> On Fri, Jul 04, 2025 at 04:19:48PM +0200, Thomas Weißschuh wrote:
> > +static __attribute__((unused))
> > +int sys_clock_nanosleep(clockid_t clockid, int flags, const struct timespec *rqtp,
> > +			struct timespec *rmtp)
> > +{
> > +#if defined(__NR_clock_nanosleep)
> > +	return my_syscall4(__NR_clock_nanosleep, clockid, flags, rqtp, rmtp);
> > +#elif defined(__NR_clock_nanosleep_time64)
> > +	struct __kernel_timespec krqtp, krmtp;
> > +	int ret;
> > +
> > +	__nolibc_timespec_user_to_kernel(rqtp, &krqtp);
> > +	ret = my_syscall4(__NR_clock_nanosleep_time64, clockid, flags, &krqtp, &krmtp);
> > +	if (rmtp)
> > +		__nolibc_timespec_kernel_to_user(&krmtp, rmtp);
> > +	return ret;
> > +#else
> > +	return __nolibc_enosys(__func__, clockid, flags, rqtp, rmtp);
> > +#endif
> 
> I don't know which archs do not have clock_nanosleep, but if it becomes
> needed on some of them, we could probably fall back to pslelect() if
> available, of course, and ignore the clockid.

No architecture should ever run into the #else.
It is mostly for completeness and consistency with other architectures.
As for falling back to pselect(), the clockid is indeed important :-)

> Acked-by: Willy Tarreau <w@1wt.eu>

Thanks!