core: wait until we daemonized before setting up signals (bgo #683932)

If we mask signals before daemonizing, the daemon process will not be
able to handle them, and thus would be unkillable with anything other
than SIGKILL.

src/main.c

@@ -401,10 +401,6 @@ main (int argc, char *argv[])
 		exit (1);
 	}
 
-	/* Set up unix signal handling */
-	if (!setup_signals ())
-		exit (1);
-
 	/* Set locale to be able to use environment variables */
 	setlocale (LC_ALL, "");
 
@@ -501,6 +497,10 @@ main (int argc, char *argv[])
 			wrote_pidfile = TRUE;
 	}
 
+	/* Set up unix signal handling - before creating threads, but after daemonizing! */
+	if (!setup_signals ())
+		exit (1);
+
 	if (g_fatal_warnings) {
 		GLogLevelFlags fatal_mask;