This is an automated email from the ASF dual-hosted git repository.
xiaoxiang pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/nuttx.git
The following commit(s) were added to refs/heads/master by this push:
new bc561c677a5 sched/sleep: Add nxched_nanosleep() API
bc561c677a5 is described below
commit bc561c677a59a48a6683ef5b31f0b3e5867e4a11
Author: wangchengdong <[email protected]>
AuthorDate: Sun Nov 23 23:18:40 2025 +0800
sched/sleep: Add nxched_nanosleep() API
Introduce the nxched_nanosleep() API to provide a lightweight
nanosecond-level sleep based on nxsched_ticksleep().
This API offers the same functionality as nxsig_nanosleep() but without
signal-related overhead, making it suitable for implementing libc
sleep() or usleep() when signals are disabled.
Signed-off-by: Chengdong Wang [email protected]
---
include/nuttx/sched.h | 22 ++++++++++++++
sched/sched/sched_sleep.c | 73 +++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 95 insertions(+)
diff --git a/include/nuttx/sched.h b/include/nuttx/sched.h
index 53dbe6eae67..e5f5b68a031 100644
--- a/include/nuttx/sched.h
+++ b/include/nuttx/sched.h
@@ -1817,6 +1817,28 @@ void nxsched_msleep(unsigned int msec);
void nxsched_sleep(unsigned int sec);
+/****************************************************************************
+ * Name: nxsched_nanosleep
+ *
+ * Description:
+ * Internal nanosleep implementation used by the scheduler. This function
+ * converts the requested sleep interval into system ticks, performs a
+ * tick-based blocking sleep, and optionally returns the remaining time if
+ * the sleep is interrupted by a signal.
+ *
+ * Input Parameters:
+ * rqtp - Requested sleep interval (may be NULL)
+ * rmtp - Remaining time returned when interrupted (optional, may be NULL)
+ *
+ * Returned Value:
+ * Returns OK (0) on success. Returns -EINVAL for an invalid timespec
+ * argument and -EAGAIN for a zero-length timeout, as required by POSIX.
+ *
+ ****************************************************************************/
+
+int nxsched_nanosleep(FAR const struct timespec *rqtp,
+ FAR struct timespec *rmtp);
+
#undef EXTERN
#if defined(__cplusplus)
}
diff --git a/sched/sched/sched_sleep.c b/sched/sched/sched_sleep.c
index 9cfa03bcb09..6d2dc424574 100644
--- a/sched/sched/sched_sleep.c
+++ b/sched/sched/sched_sleep.c
@@ -221,3 +221,76 @@ void nxsched_sleep(unsigned int sec)
{
nxsched_ticksleep(SEC2TICK(sec));
}
+
+/****************************************************************************
+ * Name: nxsched_nanosleep
+ *
+ * Description:
+ * Internal nanosleep implementation used by the scheduler. This function
+ * converts the requested sleep interval into system ticks, performs a
+ * tick-based blocking sleep, and optionally returns the remaining time if
+ * the sleep is interrupted by a signal.
+ *
+ * Input Parameters:
+ * rqtp - Requested sleep interval (may be NULL)
+ * rmtp - Remaining time returned when interrupted (optional, may be NULL)
+ *
+ * Returned Value:
+ * Returns OK (0) on success. Returns -EINVAL for an invalid timespec
+ * argument and -EAGAIN for a zero-length timeout, as required by POSIX.
+ *
+ ****************************************************************************/
+
+int nxsched_nanosleep(FAR const struct timespec *rqtp,
+ FAR struct timespec *rmtp)
+{
+ clock_t ticks;
+ clock_t expect = 0;
+ clock_t stop;
+
+ /* Validate the input timespec */
+
+ if (rqtp && (rqtp->tv_nsec < 0 || rqtp->tv_nsec >= 1000000000))
+ {
+ return -EINVAL;
+ }
+
+ /* Zero-length sleep: Yield the processor and return -EAGAIN */
+
+ if (rqtp && rqtp->tv_sec == 0 && rqtp->tv_nsec == 0)
+ {
+ sched_yield();
+ return -EAGAIN;
+ }
+
+ /* Convert the requested interval to system ticks */
+
+ ticks = clock_time2ticks(rqtp);
+
+ /* Compute the absolute tick value when the sleep should expire.
+ * This is used later to determine the remaining time after interruption.
+ */
+
+ expect = clock_delay2abstick(ticks);
+
+ /* Perform the blocking tick-based sleep */
+
+ nxsched_ticksleep(ticks);
+
+ /* Capture the current tick count after waking up */
+
+ stop = clock_systime_ticks();
+
+ /* If the caller provided a buffer for the remaining time, compute how much
+ * of the original interval is left. If the sleep expired normally,
+ * expect <= stop and the remaining time becomes zero.
+ */
+
+ if (rmtp)
+ {
+ clock_ticks2time(rmtp,
+ clock_compare(stop, expect) ? expect - stop : 0);
+ }
+
+ return OK;
+}
