Fix wait loop and void cast (#24)

* Simplify EINTR/ECANCEL error handling

1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx

* Unify the void cast usage

1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro

wireless/bluetooth/bt_conn.c

@@ -149,13 +149,7 @@ static int conn_tx_kthread(int argc, FAR char *argv[])
 
       wlinfo("calling nxsem_wait\n");
 
-      do
-        {
-          ret = nxsem_wait(&g_btdev.le_pkts_sem);
-        }
-      while (ret == -EINTR);
-
-      DEBUGASSERT(ret == OK);
+      nxsem_wait_uninterruptible(&g_btdev.le_pkts_sem);
 
       /* Check for disconnection */
 
@@ -574,13 +568,7 @@ void bt_conn_set_state(FAR struct bt_conn_s *conn,
            * zero when we complete this.
            */
 
-          do
-            {
-              ret = nxsem_wait(&g_conn_handoff.sync_sem);
-            }
-          while (ret == -EINTR);
-
-          DEBUGASSERT(ret == OK);
+          nxsem_wait_uninterruptible(&g_conn_handoff.sync_sem);
 
           /* Start the Tx connection kernel thread */
 
@@ -595,13 +583,7 @@ void bt_conn_set_state(FAR struct bt_conn_s *conn,
            * sem_count at -1.  It will be zero again when we continue.
            */
 
-          do
-            {
-              ret = nxsem_wait(&g_conn_handoff.sync_sem);
-            }
-          while (ret == -EINTR);
-
-          DEBUGASSERT(ret == OK);
+          nxsem_wait_uninterruptible(&g_conn_handoff.sync_sem);
           nxsem_post(&g_conn_handoff.sync_sem);
         }
         break;

wireless/bluetooth/bt_hcicore.c

@@ -439,7 +439,7 @@ static void hci_num_completed_packets(FAR struct bt_buf_s *buf)
 
       while (count--)
         {
-          sem_post(&g_btdev.le_pkts_sem);
+          nxsem_post(&g_btdev.le_pkts_sem);
         }
     }
 }
@@ -978,13 +978,7 @@ static int hci_tx_kthread(int argc, FAR char *argv[])
 
       /* Wait until ncmd > 0 */
 
-      do
-        {
-          ret = nxsem_wait(&g_btdev.ncmd_sem);
-        }
-      while (ret == -EINTR);
-
-      DEBUGASSERT(ret >= 0);
+      nxsem_wait_uninterruptible(&g_btdev.ncmd_sem);
 
       /* Get next command - wait if necessary */
 
@@ -1765,13 +1759,7 @@ int bt_hci_cmd_send_sync(uint16_t opcode, FAR struct bt_buf_s *buf,
            * released while we are waiting.
            */
 
-          do
-            {
-              /* The timed wait could also be awakened by a signal */
-
-              ret = nxsem_timedwait(&sync_sem, &abstime);
-            }
-          while (ret == -EINTR);
+          nxsem_timedwait_uninterruptible(&sync_sem, &abstime);
         }
 
       sched_unlock();

wireless/bluetooth/bt_ioctl.c

@@ -157,7 +157,6 @@ static void btnet_scan_callback(FAR const bt_addr_le_t *addr, int8_t rssi,
   uint8_t nexttail;
   uint8_t head;
   uint8_t tail;
-  int ret;
 
   if (!g_scanstate.bs_scanning)
     {
@@ -173,14 +172,7 @@ static void btnet_scan_callback(FAR const bt_addr_le_t *addr, int8_t rssi,
 
   /* Get exclusive access to the scan data */
 
-  while ((ret = nxsem_wait(&g_scanstate.bs_exclsem)) < 0)
-    {
-      DEBUGASSERT(ret == -EINTR || ret == -ECANCELED);
-      if (ret != -EINTR)
-        {
-          return;
-        }
-    }
+  nxsem_wait_uninterruptible(&g_scanstate.bs_exclsem);
 
   /* Add the scan data to the cache */
 
@@ -260,7 +252,6 @@ static int btnet_scan_result(FAR struct bt_scanresponse_s *result,
       ret = nxsem_wait(&g_scanstate.bs_exclsem);
       if (ret < 0)
         {
-          DEBUGASSERT(ret == -EINTR || ret == -ECANCELED);
           return ret;
         }
     }

wireless/bluetooth/bt_netdev.c

@@ -543,12 +543,12 @@ static void btnet_txpoll_work(FAR void *arg)
 
   /* Then perform the poll */
 
-  (void)devif_timer(&priv->bd_dev.r_dev, TXPOLL_WDDELAY, btnet_txpoll_callback);
+  devif_timer(&priv->bd_dev.r_dev, TXPOLL_WDDELAY, btnet_txpoll_callback);
 
   /* Setup the watchdog poll timer again */
 
-  (void)wd_start(priv->bd_txpoll, TXPOLL_WDDELAY, btnet_txpoll_expiry, 1,
-                 (wdparm_t)priv);
+  wd_start(priv->bd_txpoll, TXPOLL_WDDELAY, btnet_txpoll_expiry, 1,
+           (wdparm_t)priv);
   net_unlock();
 }
 
@@ -627,8 +627,8 @@ static int btnet_ifup(FAR struct net_driver_s *netdev)
 
       /* Set and activate a timer process */
 
-      (void)wd_start(priv->bd_txpoll, TXPOLL_WDDELAY, btnet_txpoll_expiry,
-                     1, (wdparm_t)priv);
+      wd_start(priv->bd_txpoll, TXPOLL_WDDELAY, btnet_txpoll_expiry,
+               1, (wdparm_t)priv);
 
       /* The interface is now up */
 
@@ -724,7 +724,7 @@ static void btnet_txavail_work(FAR void *arg)
 
       /* Then poll the network for new XMIT data */
 
-      (void)devif_poll(&priv->bd_dev.r_dev, btnet_txpoll_callback);
+      devif_poll(&priv->bd_dev.r_dev, btnet_txpoll_callback);
     }
 
   net_unlock();