Fix the bug that netlink receive wait does not hang up

Signed-off-by: wangyingdong <[email protected]>

net/netlink/netlink.h

@@ -428,16 +428,21 @@ netlink_tryget_response(FAR struct netlink_conn_s *conn);
  *   Note:  The network will be momentarily locked to support exclusive
  *   access to the pending response list.
  *
+ * Input Parameters:
+ *   conn     - The Netlink connection
+ *   response - The next response from the head of the pending response list
+ *              is returned.  This function will block until a response is
+ *              received if the pending response list is empty.  NULL will be
+ *              returned only in the event of a failure.
+ *
  * Returned Value:
- *   The next response from the head of the pending response list is
- *   returned.  This function will block until a response is received if
- *   the pending response list is empty.  NULL will be returned only in the
- *   event of a failure.
+ *   Zero (OK) is returned if the notification was successfully set up.
+ *   A negated error value is returned if an unexpected error occurred
  *
  ****************************************************************************/
 
-FAR struct netlink_response_s *
-netlink_get_response(FAR struct netlink_conn_s *conn);
+int netlink_get_response(FAR struct netlink_conn_s *conn,
+                         FAR struct netlink_response_s **response);
 
 /****************************************************************************
  * Name: netlink_check_response

net/netlink/netlink_conn.c

@@ -403,19 +403,23 @@ netlink_tryget_response(FAR struct netlink_conn_s *conn)
  *   Note:  The network will be momentarily locked to support exclusive
  *   access to the pending response list.
  *
+ * Input Parameters:
+ *   conn     - The Netlink connection
+ *   response - The next response from the head of the pending response list
+ *              is returned.  This function will block until a response is
+ *              received if the pending response list is empty.  NULL will be
+ *              returned only in the event of a failure.
+ *
  * Returned Value:
- *   The next response from the head of the pending response list is
- *   returned.  This function will block until a response is received if
- *   the pending response list is empty.  NULL will be returned only in the
- *   event of a failure.
+ *   Zero (OK) is returned if the notification was successfully set up.
+ *   A negated error value is returned if an unexpected error occurred
  *
  ****************************************************************************/
 
-FAR struct netlink_response_s *
-netlink_get_response(FAR struct netlink_conn_s *conn)
+int netlink_get_response(FAR struct netlink_conn_s *conn,
+                         FAR struct netlink_response_s **response)
 {
-  FAR struct netlink_response_s *resp;
-  int ret;
+  int ret = OK;
 
   DEBUGASSERT(conn != NULL);
 
@@ -425,7 +429,7 @@ netlink_get_response(FAR struct netlink_conn_s *conn)
    */
 
   net_lock();
-  while ((resp = netlink_tryget_response(conn)) == NULL)
+  while ((*response = netlink_tryget_response(conn)) == NULL)
     {
       sem_t waitsem;
 
@@ -447,7 +451,7 @@ netlink_get_response(FAR struct netlink_conn_s *conn)
         {
           /* Wait for a response to be queued */
 
-          nxsem_post(&waitsem);
+          ret = net_sem_wait(&waitsem);
         }
 
       /* Clean-up the semaphore */
@@ -464,7 +468,7 @@ netlink_get_response(FAR struct netlink_conn_s *conn)
     }
 
   net_unlock();
-  return resp;
+  return ret;
 }
 
 /****************************************************************************

net/netlink/netlink_sockif.c

@@ -658,6 +658,7 @@ static ssize_t netlink_recvmsg(FAR struct socket *psock,
   FAR socklen_t *fromlen = &msg->msg_namelen;
   FAR struct netlink_response_s *entry;
   FAR struct socket_conn_s *conn;
+  int ret = OK;
 
   DEBUGASSERT(from == NULL ||
               (fromlen != NULL && *fromlen >= sizeof(struct sockaddr_nl)));
@@ -678,13 +679,15 @@ static ssize_t netlink_recvmsg(FAR struct socket *psock,
           return -EAGAIN;
         }
 
-      /* Wait for the response.  This should always succeed. */
+      /* Wait for the response. */
+
+      ret = netlink_get_response(psock->s_conn, &entry);
+
+      /* If interrupted by signals, return errno */
 
-      entry = netlink_get_response(psock->s_conn);
-      DEBUGASSERT(entry != NULL);
       if (entry == NULL)
         {
-          return -EPIPE;
+          return ret;
         }
     }