add onepass option to exit after initial sync

default.lua

@@ -120,7 +120,14 @@ default.collect = function
 				agent.target,
 				' finished.'
 			)
-
+            if settings('onepass')
+            then
+                log(
+                    'Normal', 
+                    'onepass config set, exiting'
+                )
+                terminate( 0 )
+            end
 			return 'ok'
 		elseif rc == 'again'
 		then

lsyncd.c

@@ -91,6 +91,7 @@ struct settings settings = {
 	.log_facility = LOG_USER,
 	.log_level    = LOG_NOTICE,
 	.nodaemon     = false,
+	.onepass      = false,
 };
 
 
@@ -1630,6 +1631,10 @@ l_configure( lua_State *L )
 	{
 		settings.nodaemon = true;
 	}
+	else if( !strcmp( command, "onepass" ) )
+	{
+		settings.onepass = true;
+	}
 	else if( !strcmp( command, "logfile" ) )
 	{
 		const char * file = luaL_checkstring( L, 2 );

lsyncd.h

@@ -57,6 +57,7 @@ extern struct settings {
 	int log_facility; // The syslog facility
 	int log_level;    // -1 logs everything, 0 normal mode, LOG_ERROR errors only.
 	bool nodaemon;    // True if Lsyncd shall not daemonize.
+	bool onepass;     // True if Lsyncd should exit after first sync pass
 	char * pidfile;   // If not NULL Lsyncd writes its pid into this file.
 
 } settings;

lsyncd.lua

@@ -75,6 +75,7 @@ local settingsCheckgauge =
 	logfile        = true,
 	pidfile        = true,
 	nodaemon	   = true,
+	onepass 	   = true,
 	statusFile     = true,
 	statusInterval = true,
 	logfacility    = true,
@@ -4614,6 +4615,7 @@ OPTIONS:
   -log    [Category]  Turns on logging for a debug category
   -logfile FILE       Writes log to FILE (DEFAULT: uses syslog)
   -nodaemon           Does not detach and logs to stdout/stderr
+  -onepass            Sync once and exit
   -pidfile FILE       Writes Lsyncds PID into FILE
   -runner FILE        Loads Lsyncds lua part from FILE
   -version            Prints versions and exits
@@ -4729,6 +4731,15 @@ function runner.configure( args, monitors )
 			end
 		},
 
+		onepass =
+		{
+			0,
+			function
+            ( )
+				clSettings.onepass = true
+			end
+		},
+
 		pidfile =
 		{
 			1,
@@ -4968,6 +4979,11 @@ function runner.initialize( firstTime )
 		lsyncd.configure( 'nodaemon' )
 	end
 
+	if uSettings.onepass
+	then
+		lsyncd.configure( 'onepass' )
+	end
+
 	if uSettings.logfile
 	then
 		lsyncd.configure( 'logfile', uSettings.logfile )