Simplify handling of terminating signals in all libcharon wrappers

Closes strongswan/strongswan#182.

src/charon-cmd/charon-cmd.c

@@ -134,14 +134,10 @@ static int run()
 				break;
 			}
 			case SIGINT:
-			{
-				DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
-				charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
-				return 0;
-			}
 			case SIGTERM:
 			{
-				DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
+				DBG1(DBG_DMN, "%s received, shutting down",
+					 sig == SIGINT ? "SIGINT" : "SIGTERM");
 				charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
 				return 0;
 			}

src/charon-nm/charon-nm.c

@@ -94,14 +94,10 @@ static void run()
 		switch (sig)
 		{
 			case SIGINT:
-			{
-				DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
-				charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
-				return;
-			}
 			case SIGTERM:
 			{
-				DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
+				DBG1(DBG_DMN, "%s received, shutting down",
+					 sig == SIGINT ? "SIGINT" : "SIGTERM");
 				charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
 				return;
 			}

src/charon-tkm/src/charon-tkm.c

@@ -118,14 +118,10 @@ static void run()
 		switch (sig)
 		{
 			case SIGINT:
-			{
-				DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
-				charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
-				return;
-			}
 			case SIGTERM:
 			{
-				DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
+				DBG1(DBG_DMN, "%s received, shutting down",
+					 sig == SIGINT ? "SIGINT" : "SIGTERM");
 				charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
 				return;
 			}

src/charon/charon.c

@@ -126,14 +126,10 @@ static void run()
 				break;
 			}
 			case SIGINT:
-			{
-				DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
-				charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
-				return;
-			}
 			case SIGTERM:
 			{
-				DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
+				DBG1(DBG_DMN, "%s received, shutting down",
+					 sig == SIGINT ? "SIGINT" : "SIGTERM");
 				charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
 				return;
 			}

src/frontends/osx/charon-xpc/charon-xpc.c

@@ -92,11 +92,9 @@ static int run()
 		switch (sig)
 		{
 			case SIGINT:
-				DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
-				charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
-				return 0;
 			case SIGTERM:
-				DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
+				DBG1(DBG_DMN, "%s received, shutting down",
+					 sig == SIGINT ? "SIGINT" : "SIGTERM");
 				charon->bus->alert(charon->bus, ALERT_SHUTDOWN_SIGNAL, sig);
 				return 0;
 		}