Expose the main event loop so modules can use it.

Initialize, but do not start, event loop earlier.

Do it through a new API function that leaves room for enhancements
such as a second thread/event loop for modules that can do their
events in a threadsafe manner.  But don't actually do that yet.

src/include/radiusd.h

@@ -722,7 +722,14 @@ rad_listen_t *listener_find_byipaddr(fr_ipaddr_t const *ipaddr, int port,
 int rad_status_server(REQUEST *request);
 
 /* event.c */
-int radius_event_init(CONF_SECTION *cs, bool spawn_flag);
+typedef enum event_corral_t {
+	EVENT_CORRAL_MAIN = 0,	//!< Always main thread event list
+	EVENT_CORRAL_AUX	//!< Maybe main thread or one shared by modules
+} event_corral_t;
+
+fr_event_list_t *radius_event_list_corral(event_corral_t hint);
+int radius_event_init(bool spawn_flag, bool aux_loops);
+int radius_event_start(CONF_SECTION *cs, bool spawn_flag);
 void radius_event_free(void);
 int radius_event_process(void);
 int event_new_fd(rad_listen_t *listener);

src/main/process.c

@@ -49,10 +49,15 @@ extern fr_cond_t *debug_condition;
 
 static bool spawn_flag = false;
 static bool just_started = true;
-time_t				fr_start_time;
+time_t fr_start_time = (time_t)-1;
 static fr_packet_list_t *pl = NULL;
 static fr_event_list_t *el = NULL;
 
+fr_event_list_t *radius_event_list_corral(UNUSED event_corral_t hint) {
+	/* Currently we do not run a second event loop for modules. */
+	return el;
+}
+
 static char const *action_codes[] = {
 	"INVALID",
 	"run",
@@ -941,14 +946,14 @@ STATE_MACHINE_DECL(request_common)
 
 	TRACE_STATE_MACHINE;
 	ASSERT_MASTER;
-	
+
 	/*
 	 *	Bail out as early as possible.
 	 */
 	if (request->master_state == REQUEST_STOP_PROCESSING) {
 		request_done(request, REQUEST_DONE);
 		return;
-	}	       
+	}
 
 	switch (action) {
 	case FR_ACTION_DUP:
@@ -4287,16 +4292,24 @@ static void event_signal_handler(UNUSED fr_event_list_t *xel,
 /*
  *	Externally-visibly functions.
  */
-int radius_event_init(CONF_SECTION *cs, bool have_children)
+int radius_event_init(UNUSED bool have_children, UNUSED bool aux_loops) {
+	el = fr_event_list_create(NULL, event_status);
+	if (!el) return 0;
+
+	return 1;
+	/* If have_children/threaded we could init an auxiliary loop */
+}
+
+int radius_event_start(CONF_SECTION *cs, bool have_children)
 {
 	rad_listen_t *head = NULL;
 
-	if (el) return 0;
+	if (fr_start_time != (time_t)-1) return 0;
 
 	time(&fr_start_time);
 
 	el = fr_event_list_create(NULL, event_status);
-	if (!el) return 0;
+	if (fr_start_time == (time_t)-1) return 0;
 
 	pl = fr_packet_list_create(0);
 	if (!pl) return 0;	/* leak el */

src/main/radiusd.c

@@ -317,6 +317,14 @@ int main(int argc, char *argv[])
 		version();
 	}
 
+	/*
+	 *  Initialize any event loops just enough so module instantiations
+	 *  can add fd/event to them, but do not start them yet.
+	 */
+	if (!radius_event_init(spawn_flag, 0)) {
+		exit(EXIT_FAILURE);
+	}
+
 	/*  Read the configuration files, BEFORE doing anything else.  */
 	if (read_mainconfig(0) < 0) {
 		exit(EXIT_FAILURE);
@@ -437,9 +445,9 @@ int main(int argc, char *argv[])
 	radius_pid = getpid();
 
 	/*
-	 *	Initialize the event pool, including threads.
+	 *	Start the event loop(s) and threads.
 	 */
-	radius_event_init(mainconfig.config, spawn_flag);
+	radius_event_start(mainconfig.config, spawn_flag);
 
 	/*
 	 *	Now that we've set everything up, we can install the signal