From 0c9a4ac4f91013fdde36fa39cfe85f6256e3da1c Mon Sep 17 00:00:00 2001
From: liuhaiyang <liuhaiyang@xiaomi.com>
Date: Mon, 27 Aug 2018 06:07:50 -0600
Subject: [PATCH] nclude/nuttx/semaphore: apply the semaphore wait function
 nxsem_wait_uninterruptible().  The function nxsem_wait_uninterruptible() is a
 wrapped version of nxsem_wait(), which is uninterruptible and convenient for
 use.

---
 include/nuttx/semaphore.h | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/include/nuttx/semaphore.h b/include/nuttx/semaphore.h
index c736086f117..4a44f2f4ea6 100644
--- a/include/nuttx/semaphore.h
+++ b/include/nuttx/semaphore.h
@@ -42,6 +42,7 @@
 
 #include <nuttx/config.h>
 
+#include <errno.h>
 #include <semaphore.h>
 
 #include <nuttx/clock.h>
@@ -523,6 +524,37 @@ int nxsem_setprotocol(FAR sem_t *sem, int protocol);
 
 int sem_setprotocol(FAR sem_t *sem, int protocol);
 
+/****************************************************************************
+ * Name: nxsem_wait_uninterruptible
+ *
+ * Description:
+ *   This function is wrapped version of nxsem_wait(), which is uninterruptible
+ *   and convenient for use.
+ *
+ * Parameters:
+ *   sem - Semaphore descriptor.
+ *
+ * Return Value:
+ *   Zero(OK) - On success
+ *   EINVAL - Invalid attempt to get the semaphore
+ *
+ ****************************************************************************/
+
+static inline int nxsem_wait_uninterruptible(FAR sem_t *sem)
+{
+  int ret;
+
+  do
+    {
+      /* Take the semaphore (perhaps waiting) */
+
+      ret = nxsem_wait(sem);
+    }
+  while (ret == -EINTR || ret == -ECANCELED);
+
+  return ret;
+}
+
 #undef EXTERN
 #ifdef __cplusplus
 }