[thread-netif] change Up()/Down() to void (no return) (#3513)

include/openthread/ip6.h

@@ -183,15 +183,16 @@ typedef struct otMessageInfo
 } otMessageInfo;
 
 /**
- * This function brings up the IPv6 interface.
+ * This function brings up/down the IPv6 interface.
  *
  * Call this function to enable/disable IPv6 communication.
  *
  * @param[in] aInstance A pointer to an OpenThread instance.
  * @param[in] aEnabled  TRUE to enable IPv6, FALSE otherwise.
  *
- * @retval OT_ERROR_NONE          Successfully enabled the IPv6 interface,
- *                                or the interface was already enabled.
+ * @retval OT_ERROR_NONE            Successfully brought the IPv6 interface up/down.
+ * @retval OT_ERROR_INVALID_STATE   IPv6 interface is not available since device is operating in raw-link mode
+ *                                  (applicable only when `OPENTHREAD_ENABLE_RAW_LINK_API` feature is enabled).
  *
  */
 OTAPI otError OTCALL otIp6SetEnabled(otInstance *aInstance, bool aEnabled);

src/core/api/ip6_api.cpp

@@ -48,24 +48,22 @@ otError otIp6SetEnabled(otInstance *aInstance, bool aEnabled)
     otError   error    = OT_ERROR_NONE;
     Instance &instance = *static_cast<Instance *>(aInstance);
 
+#if OPENTHREAD_ENABLE_RAW_LINK_API
+    VerifyOrExit(!instance.GetLinkRaw().IsEnabled(), error = OT_ERROR_INVALID_STATE);
+#endif
+
     if (aEnabled)
     {
-#if OPENTHREAD_ENABLE_RAW_LINK_API
-        VerifyOrExit(!instance.GetLinkRaw().IsEnabled(), error = OT_ERROR_INVALID_STATE);
-#endif // OPENTHREAD_ENABLE_RAW_LINK_API
-        error = instance.GetThreadNetif().Up();
+        instance.GetThreadNetif().Up();
     }
     else
     {
-#if OPENTHREAD_ENABLE_RAW_LINK_API
-        VerifyOrExit(!instance.GetLinkRaw().IsEnabled(), error = OT_ERROR_INVALID_STATE);
-#endif // OPENTHREAD_ENABLE_RAW_LINK_API
-        error = instance.GetThreadNetif().Down();
+        instance.GetThreadNetif().Down();
     }
 
 #if OPENTHREAD_ENABLE_RAW_LINK_API
 exit:
-#endif // OPENTHREAD_ENABLE_RAW_LINK_API
+#endif
     return error;
 }
 

src/core/thread/thread_netif.cpp

@@ -113,7 +113,7 @@ ThreadNetif::ThreadNetif(Instance &aInstance)
     memset(mSlaacAddresses, 0, sizeof(mSlaacAddresses));
 }
 
-otError ThreadNetif::Up(void)
+void ThreadNetif::Up(void)
 {
     VerifyOrExit(!mIsUp);
 
@@ -139,10 +139,10 @@ otError ThreadNetif::Up(void)
     GetNotifier().Signal(OT_CHANGED_THREAD_NETIF_STATE);
 
 exit:
-    return OT_ERROR_NONE;
+    return;
 }
 
-otError ThreadNetif::Down(void)
+void ThreadNetif::Down(void)
 {
     VerifyOrExit(mIsUp);
 
@@ -171,7 +171,7 @@ otError ThreadNetif::Down(void)
     GetNotifier().Signal(OT_CHANGED_THREAD_NETIF_STATE);
 
 exit:
-    return OT_ERROR_NONE;
+    return;
 }
 
 otError ThreadNetif::GetLinkAddress(Ip6::LinkAddress &address) const

src/core/thread/thread_netif.hpp

@@ -109,13 +109,13 @@ public:
      * This method enables the Thread network interface.
      *
      */
-    otError Up(void);
+    void Up(void);
 
     /**
      * This method disables the Thread network interface.
      *
      */
-    otError Down(void);
+    void Down(void);
 
     /**
      * This method indicates whether or not the Thread network interface is enabled.