Release logging related resources when mce makes an orderly exit

While closing logging is not necessary, doing it reduces noise during
memory leak debugging. In the code the logging cleanup was made on
abnormal exit paths, but omitted when making an orderly exit.

Remove unnecessary mce_log_close() calls from abnormal exit paths.

Perform logging cleanup actions on normal exit.

mce-log.c

@@ -36,6 +36,15 @@ static unsigned int logverbosity = LL_WARN;	/**< Log verbosity */
 static int logtype = MCE_LOG_STDERR;		/**< Output for log messages */
 static char *logname = NULL;
 
+/** Get process identity to use for logging
+ *
+ * Will default to "mce" before mce_log_open() and after mce_log_close().
+ */
+static const char *mce_log_name(void)
+{
+	return logname ?: "mce";
+}
+
 /** Get monotonic time as struct timeval */
 static void monotime(struct timeval *tv)
 {
@@ -54,7 +63,7 @@ static void timestamp(struct timeval *tv)
 	if( diff.tv_sec >= 4 ) {
 		timersub(tv, &start, &diff);
 		fprintf(stderr, "%s: T+%ld.%03ld %s\n\n",
-			logname,
+			mce_log_name(),
 			(long)diff.tv_sec, (long)(diff.tv_usec/1000),
 			"END OF BURST");
 		start = *tv;
@@ -179,7 +188,7 @@ void mce_log_file(loglevel_t loglevel, const char *const file,
 			struct timeval tv;
 			timestamp(&tv);
 			fprintf(stderr, "%s: T+%ld.%03ld %s: %s\n",
-				logname,
+				mce_log_name(),
 				(long)tv.tv_sec, (long)(tv.tv_usec/1000),
 				mce_log_level_tag(loglevel),
 				msg);
@@ -214,20 +223,21 @@ void mce_log_set_verbosity(const int verbosity)
 void mce_log_open(const char *const name, const int facility, const int type)
 {
 	logtype = type;
+	logname = g_strdup(name);
 
 	if (logtype == MCE_LOG_SYSLOG)
 		openlog(name, LOG_PID | LOG_NDELAY, facility);
-	else
-		logname = g_strdup(name);
 }
 
 /**
  * Close log
  */
 void mce_log_close(void)
 {
+	/* Logging (to stderr) after this will use default identity */
 	g_free(logname), logname = 0;
 
+	/* Any further syslog() calls will automatically reopen */
 	if (logtype == MCE_LOG_SYSLOG)
 		closelog();
 }

mce.c

@@ -443,7 +443,6 @@ static gboolean daemonize(void)
 		/* Parent - Failure */
 		mce_log(LL_CRIT, "daemonize: fork failed: %s",
 			g_strerror(errno));
-		mce_log_close();
 		exit(EXIT_FAILURE);
 
 	case 0:
@@ -471,7 +470,6 @@ static gboolean daemonize(void)
 				mce_log(LL_CRIT,
 					"close() was interrupted more than "
 					"10 times. Exiting.");
-				mce_log_close();
 				exit(EXIT_FAILURE);
 			}
 
@@ -489,7 +487,6 @@ static gboolean daemonize(void)
 					"Failed to close() fd %d; %s. "
 					"Exiting.",
 					i + 1, g_strerror(errno));
-				mce_log_close();
 				exit(EXIT_FAILURE);
 			}
 		} else {
@@ -501,23 +498,20 @@ static gboolean daemonize(void)
 		mce_log(LL_CRIT,
 			"Cannot open `/dev/null'; %s. Exiting.",
 			g_strerror(errno));
-		mce_log_close();
 		exit(EXIT_FAILURE);
 	}
 
 	if ((dup(i) == -1)) {
 		mce_log(LL_CRIT,
 			"Failed to dup() `/dev/null'; %s. Exiting.",
 			g_strerror(errno));
-		mce_log_close();
 		exit(EXIT_FAILURE);
 	}
 
 	if ((dup(i) == -1)) {
 		mce_log(LL_CRIT,
 			"Failed to dup() `/dev/null'; %s. Exiting.",
 			g_strerror(errno));
-		mce_log_close();
 		exit(EXIT_FAILURE);
 	}
 
@@ -529,7 +523,6 @@ static gboolean daemonize(void)
 		mce_log(LL_CRIT,
 			"Failed to chdir() to `/tmp'; %s. Exiting.",
 			g_strerror(errno));
-		mce_log_close();
 		exit(EXIT_FAILURE);
 	}
 
@@ -538,13 +531,11 @@ static gboolean daemonize(void)
 		mce_log(LL_CRIT,
 			"Cannot open lockfile; %s. Exiting.",
 			g_strerror(errno));
-		mce_log_close();
 		exit(EXIT_FAILURE);
 	}
 
 	if (lockf(i, F_TLOCK, 0) == -1) {
 		mce_log(LL_CRIT, "Already running. Exiting.");
-		mce_log_close();
 		exit(EXIT_FAILURE);
 	}
 
@@ -955,7 +946,6 @@ int main(int argc, char **argv)
 	if( !mce_dbus_init(mce_args.systembus) ) {
 		mce_log(LL_CRIT,
 			"Failed to initialise D-Bus");
-		mce_log_close();
 		exit(EXIT_FAILURE);
 	}
 
@@ -965,7 +955,6 @@ int main(int argc, char **argv)
 	if (mce_gconf_init() == FALSE) {
 		mce_log(LL_CRIT,
 			"Cannot connect to default GConf engine");
-		mce_log_close();
 		exit(EXIT_FAILURE);
 	}
 
@@ -1076,9 +1065,8 @@ int main(int argc, char **argv)
 	/* Log a farewell message and close the log */
 	mce_log(LL_INFO, "Exiting...");
 
-	/* We do not need to explicitly close the log and doing so
-	 * would not allow logging from atexit handlers */
-	//mce_log_close();
+	/* No more logging expected */
+	mce_log_close();
 
 	return status;
 }