- SV subscriber: improved error handling when Ethernet access doesn't work; fixed potential memory leak

examples/sv_subscriber/sv_subscriber_example.c

@@ -75,6 +75,7 @@ main(int argc, char** argv)
     /* Start listening to SV messages - starts a new receiver background thread */
     SVReceiver_start(receiver);
 
+    if (SVReceiver_isRunning(receiver)) {
         signal(SIGINT, sigint_handler);
 
         while (running)
@@ -82,6 +83,10 @@ main(int argc, char** argv)
 
         /* Stop listening to SV messages */
         SVReceiver_stop(receiver);
+    }
+    else {
+        printf("Failed to start SV subscriber. Reason can be that the Ethernet interface doesn't exist or root permission are required.\n");
+    }
 
     /* Cleanup and free resources */
     SVReceiver_destroy(receiver);

src/sampled_values/sv_subscriber.c

@@ -157,39 +157,35 @@ svReceiverLoop(void* threadParameter)
 {
     SVReceiver self = (SVReceiver) threadParameter;
 
-    self->running = true;
     self->stopped = false;
 
-    if (SVReceiver_startThreadless(self)) {
-
     while (self->running) {
 
         if (SVReceiver_tick(self) == false)
             Thread_sleep(1);
     }
 
-        SVReceiver_stopThreadless(self);
-    }
-    else {
-        if (DEBUG_SV_SUBSCRIBER)
-            printf("SV_SUBSCRIBER: Failed to start SV receiver\n");
-    }
-
     self->stopped = true;
 }
 
-
 void
 SVReceiver_start(SVReceiver self)
 {
-    Thread thread = Thread_create((ThreadExecutionFunction) svReceiverLoop, (void*) self, true);
+    if (SVReceiver_startThreadless(self)) {
 
-    if (thread != NULL) {
         if (DEBUG_SV_SUBSCRIBER)
             printf("SV_SUBSCRIBER: SV receiver started for interface %s\n", self->interfaceId);
 
+        Thread thread = Thread_create((ThreadExecutionFunction) svReceiverLoop, (void*) self, true);
+
+        if (thread) {
             Thread_start(thread);
         }
+        else {
+            if (DEBUG_SV_SUBSCRIBER)
+                printf("SV_SUBSCRIBER: Failed to start thread\n");
+        }
+    }
     else {
         if (DEBUG_SV_SUBSCRIBER)
             printf("SV_SUBSCRIBER: Starting SV receiver failed for interface %s\n", self->interfaceId);
@@ -206,10 +202,12 @@ SVReceiver_isRunning(SVReceiver self)
 void
 SVReceiver_stop(SVReceiver self)
 {
-    self->running = false;
+    if (self->running) {
+        SVReceiver_stopThreadless(self);
 
         while (self->stopped == false)
             Thread_sleep(1);
+    }
 }
 
 void
@@ -218,6 +216,9 @@ SVReceiver_destroy(SVReceiver self)
     LinkedList_destroyDeep(self->subscriberList,
             (LinkedListValueDeleteFunction) SVSubscriber_destroy);
 
+    if (self->interfaceId != NULL)
+        GLOBAL_FREEMEM(self->interfaceId);
+
 #if (CONFIG_MMS_THREADLESS_STACK == 0)
         Semaphore_destroy(self->subscriberListLock);
 #endif
@@ -247,6 +248,7 @@ SVReceiver_startThreadless(SVReceiver self)
 void
 SVReceiver_stopThreadless(SVReceiver self)
 {
+    if (self->ethSocket)
         Ethernet_destroySocket(self->ethSocket);
 
     self->running = false;