Refactor state machine control functions

This refactor should have been done years ago when we first introduced
the big state machine.  The old functions service_runvel() and the oddly
named service_reload_dynamic() are actually state machine control fns,
so let relocate them.

Also in this commit, remove the global variable 'sm' and rename a few of
the critical functions to better names.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

src/api.c

@@ -47,6 +47,7 @@
 #include "private.h"
 #include "schedule.h"
 #include "service.h"
+#include "sm.h"
 #include "sig.h"
 #include "util.h"
 
@@ -275,19 +276,19 @@ static int do_reboot(int cmd, int timeout, char *buf, size_t len)
 	case INIT_CMD_REBOOT:
 		dbg("reboot");
 		halt = SHUT_REBOOT;
-		service_runlevel(6);
+		sm_runlevel(6);
 		break;
 
 	case INIT_CMD_HALT:
 		dbg("halt");
 		halt = SHUT_HALT;
-		service_runlevel(0);
+		sm_runlevel(0);
 		break;
 
 	case INIT_CMD_POWEROFF:
 		dbg("poweroff");
 		halt = SHUT_OFF;
-		service_runlevel(0);
+		sm_runlevel(0);
 		break;
 
 	case INIT_CMD_SUSPEND:
@@ -316,7 +317,7 @@ typedef struct {
 } ev_t;
 
 ev_t ev_list[] = {
-	{ "RELOAD", service_reload_dynamic   },
+	{ "RELOAD", sm_reload   },
 	{ NULL, NULL }
 };
 
@@ -437,7 +438,7 @@ static void api_cb(uev_t *w, void *arg, int events)
 				if (runlevel == INIT_LEVEL)
 					cfglevel = lvl;
 				else
-					service_runlevel(lvl);
+					sm_runlevel(lvl);
 				break;
 
 			default:
@@ -453,7 +454,7 @@ static void api_cb(uev_t *w, void *arg, int events)
 
 		case INIT_CMD_RELOAD: /* 'init q' and 'initctl reload' */
 			dbg("reload");
-			service_reload_dynamic();
+			sm_reload();
 			break;
 
 		case INIT_CMD_START_SVC:

src/cgroup.c

@@ -303,7 +303,7 @@ static void cgroup_events_cb(uev_t *w, void *arg, int events)
 
 #ifdef AUTO_RELOAD
 	if (conf_any_change())
-		service_reload_dynamic();
+		sm_reload();
 #endif
 }
 

src/cond-w.c

@@ -218,7 +218,7 @@ static int do_delete(const char *fpath, const struct stat *sb, int tflag, struct
 		err(1, "Failed removing condition %s", fpath);
 
 	cond = ptr + strlen(COND_BASE) + 1;
-	if (sm_is_in_teardown(&sm))
+	if (sm_in_reload())
 		cond_clear_noupdate(cond);
 	else
 		cond_update(cond);

src/conf.c

@@ -1577,7 +1577,7 @@ static void conf_cb(uev_t *w, void *arg, int events)
 
 #ifdef AUTO_RELOAD
 	if (conf_any_change())
-		service_reload_dynamic();
+		sm_reload();
 #endif
 }
 

src/finit.c

@@ -745,8 +745,8 @@ int main(int argc, char *argv[])
 	 * Initialize state machine and start all bootstrap tasks
 	 * NOTE: no network available!
 	 */
-	sm_init(&sm);
+	sm_init();
-	sm_step(&sm);
+	sm_step();
 
 	/*
 	 * Enter main loop to monitor /dev/initctl and services

src/service.c

@@ -1182,38 +1182,6 @@ static int service_restart(svc_t *svc)
 	return rc;
 }
 
-/**
- * service_reload_dynamic - Called on SIGHUP, 'init q' or 'initctl reload'
- *
- * This function is called when Finit has received SIGHUP to reload
- * .conf files in /etc/finit.d.  It is responsible for starting,
- * stopping and reloading (forwarding SIGHUP) to processes affected.
- */
-void service_reload_dynamic(void)
-{
-	sm_set_reload(&sm);
-	sm_step(&sm);
-}
-
-/**
- * service_runlevel - Change to a new runlevel
- * @newlevel: New runlevel to activate
- *
- * Stops all services not in @newlevel and starts, or lets continue to run,
- * those in @newlevel.  Also updates @prevlevel and active @runlevel.
- */
-void service_runlevel(int newlevel)
-{
-	if (!rescue && (runlevel == 1 || runlevel == INIT_LEVEL) && !IS_RESERVED_RUNLEVEL(newlevel))
-		networking(1);
-
-	sm_set_runlevel(&sm, newlevel);
-	sm_step(&sm);
-
-	if (!rescue && IS_RESERVED_RUNLEVEL(runlevel))
-		networking(0);
-}
-
 /*
  * Parse run/task/service arguments with support for quoted strings, both
  * single and double quotes to allow arguments containing spaces.
@@ -2137,7 +2105,7 @@ cont:
 			dbg("collected bootstrap task %s(%d), removing.", svc_ident(svc, NULL, 0), lost);
 	}
 
-	sm_step(&sm);
+	sm_step();
 }
 
 static void svc_mark_affected(char *cond)
@@ -2518,7 +2486,7 @@ static void svc_set_state(svc_t *svc, svc_state_t new_state)
 		if ((old_state == SVC_RUNNING_STATE && new_state == SVC_PAUSED_STATE) ||
 		    (old_state == SVC_PAUSED_STATE  && new_state == SVC_RUNNING_STATE))
 			; 	/* only paused during reload, don't clear conds. */
-		else if (sm_is_in_teardown(&sm))
+		else if (sm_in_reload())
 			cond_clear_noupdate(cond);
 		else
 			cond_clear(cond);
@@ -2713,7 +2681,7 @@ restart:
 			svc_set_state(svc, SVC_HALTED_STATE);
 		} else if (cond_get_agg(svc->cond) == COND_ON) {
 			/* wait until all processes have been stopped before continuing... */
-			if (sm_is_in_teardown(&sm))
+			if (sm_in_reload())
 				break;
 
 			/* Don't start if it conflicts with something else already started */
@@ -2808,15 +2776,16 @@ restart:
 
 		case COND_ON:
 			if (svc_is_changed(svc)) {
-				if (svc_nohup(svc) || !svc_is_daemon(svc))
+				if (svc_nohup(svc) || !svc_is_daemon(svc)) {
 					service_stop(svc);
-				else {
+				} else {
 					/*
 					 * wait until all processes have been
 					 * stopped before continuing...
 					 */
-					if (sm_is_in_teardown(&sm))
+					if (sm_in_reload())
 						break;
+
 					service_restart(svc);
 				}
 

src/service.h

@@ -27,12 +27,10 @@
 
 #include "svc.h"
 
-void	  service_runlevel	 (int newlevel);
 int	  service_register	 (int type, char *line, struct rlimit rlimit[], char *file);
 void      service_unregister     (svc_t *svc);
 
 void      service_runtask_clean  (void);
-void      service_reload_dynamic (void);
 void      service_update_rdeps   (void);
 void      service_mark_unavail   (void);
 

src/sig.c

@@ -94,6 +94,7 @@
 #include "private.h"
 #include "sig.h"
 #include "service.h"
+#include "sm.h"
 #include "util.h"
 #include "utmp-api.h"
 
@@ -444,7 +445,7 @@ static void sighup_cb(uev_t *w, void *arg, int events)
 	api_init(w->ctx);
 
 	/* INIT_CMD_RELOAD: 'init q', 'initctl reload', and SIGHUP */
-	service_reload_dynamic();
+	sm_reload();
 }
 
 /*
@@ -528,7 +529,7 @@ static void sigusr2_cb(uev_t *w, void *arg, int events)
 	}
 
 	halt = SHUT_OFF;
-	service_runlevel(0);
+	sm_runlevel(0);
 }
 
 /*
@@ -551,7 +552,7 @@ static void sigterm_cb(uev_t *w, void *arg, int events)
 	}
 
 	halt = SHUT_REBOOT;
-	service_runlevel(6);
+	sm_runlevel(6);
 }
 
 /*

src/sm.c

@@ -38,7 +38,24 @@
 #include "sm.h"
 #include "utmp-api.h"
 
-sm_t sm;
+typedef enum {
+	SM_BOOTSTRAP_STATE = 0,   /* Init state, bootstrap services */
+	SM_BOOTSTRAP_WAIT_STATE,  /* Waiting for bootstrap to complete */
+	SM_RUNNING_STATE,         /* Normal state, services running */
+	SM_RUNLEVEL_CHANGE_STATE, /* A runlevel change has occurred */
+	SM_RUNLEVEL_WAIT_STATE,   /* Waiting for all stopped processes to halt */
+	SM_RUNLEVEL_CLEAN_STATE,  /* Wait for post:scripts and cleanup:scripts */
+	SM_RELOAD_CHANGE_STATE,   /* A reload event has occurred */
+	SM_RELOAD_WAIT_STATE,     /* Waiting for all stopped processes to halt */
+	SM_RELOAD_CLEAN_STATE,    /* Wait for post:scripts and cleanup:scripts */
+} sm_state_t;
+
+static struct {
+	sm_state_t state;         /* Running, Changed, Waiting, ... */
+	int        newlevel;      /* Set to new runlevel on change, -1 otherwise */
+	int        reload;        /* Set on reload event, else 0  */
+	int        in_reload;   /* Set when waiting for all processes to be halted */
+} sm;
 
 #ifndef FINIT_NOLOGIN_PATH
 #define FINIT_NOLOGIN_PATH _PATH_NOLOGIN /* Stop user logging in. */
@@ -90,7 +107,7 @@ static void sm_check_bootstrap(void *work)
 	} else
 		dbg("Change to default runlevel(%d), starting all services ...", cfglevel);
 
-	service_runlevel(level);
+	sm_runlevel(level);
 
 	/* Clean up bootstrap-only tasks/services that never started */
 	dbg("Clean up all bootstrap-only tasks/services ...");
@@ -135,7 +152,7 @@ static char *sm_status(sm_state_t state)
 	return "unknown";
 }
 
-static char sm_runlevel(int lvl)
+static char sm_rl2ch(int lvl)
 {
 	if (lvl == INIT_LEVEL)
 		return 'S';
@@ -158,60 +175,39 @@ static void nologin(void)
 		erase(FINIT_NOLOGIN_PATH);
 }
 
-void sm_init(sm_t *sm)
+void sm_init(void)
 {
 	static struct wq work = {
 		.cb = sm_check_bootstrap,
 		.delay = 1000
 	};
 
-	sm->state = SM_BOOTSTRAP_STATE;
+	sm.state = SM_BOOTSTRAP_STATE;
-	sm->newlevel = -1;
+	sm.newlevel = -1;
-	sm->reload = 0;
+	sm.reload = 0;
-	sm->in_teardown = 0;
+	sm.in_reload = 0;
 
 	dbg("Starting bootstrap finalize timer ...");
 	schedule_work(&work);
 }
 
-void sm_set_runlevel(sm_t *sm, int newlevel)
+void sm_step(void)
-{
-	sm->newlevel = newlevel;
-
-	dbg("Flushing pending .conf file events ...");
-	conf_flush_events();
-}
-
-void sm_set_reload(sm_t *sm)
-{
-	sm->reload = 1;
-
-	dbg("Flushing pending .conf file events ...");
-	conf_flush_events();
-}
-
-int sm_is_in_teardown(sm_t *sm)
-{
-	return sm->in_teardown;
-}
-
-void sm_step(sm_t *sm)
 {
 	sm_state_t old_state;
 	svc_t *svc;
 
 restart:
-	old_state = sm->state;
+	old_state = sm.state;
 
 	dbg("state: %s, runlevel: %c, newlevel: %d, teardown: %d, reload: %d",
-	    sm_status(sm->state), sm_runlevel(runlevel), sm->newlevel, sm->in_teardown, sm->reload);
+	    sm_status(sm.state), sm_rl2ch(runlevel), sm.newlevel, sm.in_reload, sm.reload);
 
-	switch (sm->state) {
+	switch (sm.state) {
 	case SM_BOOTSTRAP_STATE:
 		dbg("Bootstrapping all services in runlevel S from %s", finit_conf);
 		service_step_all(SVC_TYPE_RUNTASK | SVC_TYPE_SERVICE | SVC_TYPE_SYSV);
 
-		sm->state = SM_BOOTSTRAP_WAIT_STATE;
+		sm.state = SM_BOOTSTRAP_WAIT_STATE;
 		break;
 
 	/*
@@ -232,7 +228,7 @@ restart:
 		/* Allow runparts to start */
 		cond_set_oneshot("int/bootstrap");
 
-		if (sm->newlevel == -1)
+		if (sm.newlevel == -1)
 			break;
 
 		/* Hooks that should run at the very end */
@@ -246,7 +242,7 @@ restart:
 		/* System bootstrapped, launch TTYs et al */
 		bootstrap = 0;
 		service_step_all(SVC_TYPE_RESPAWN);
-		sm->state = SM_RUNNING_STATE;
+		sm.state = SM_RUNNING_STATE;
 		break;
 
 	case SM_RUNNING_STATE:
@@ -254,26 +250,26 @@ restart:
 		service_step_all(SVC_TYPE_ANY);
 
 		/* runlevel changed? */
-		if (sm->newlevel >= 0 && sm->newlevel <= 9) {
+		if (sm.newlevel >= 0 && sm.newlevel <= 9) {
-			if (runlevel == sm->newlevel) {
+			if (runlevel == sm.newlevel) {
-				sm->newlevel = -1;
+				sm.newlevel = -1;
 				break;
 			}
-			sm->state = SM_RUNLEVEL_CHANGE_STATE;
+			sm.state = SM_RUNLEVEL_CHANGE_STATE;
 			break;
 		}
 
 		/* reload ? */
-		if (sm->reload) {
+		if (sm.reload) {
-			sm->reload = 0;
+			sm.reload = 0;
-			sm->state = SM_RELOAD_CHANGE_STATE;
+			sm.state = SM_RELOAD_CHANGE_STATE;
 		}
 		break;
 
 	case SM_RUNLEVEL_CHANGE_STATE:
 		prevlevel    = runlevel;
-		runlevel     = sm->newlevel;
+		runlevel     = sm.newlevel;
-		sm->newlevel = -1;
+		sm.newlevel = -1;
 
 		/* Restore terse mode and run hooks before shutdown */
 		if (runlevel == 0 || runlevel == 6) {
@@ -282,11 +278,11 @@ restart:
 			plugin_run_hooks(HOOK_SHUTDOWN);
 		}
 
-		dbg("Setting new runlevel --> %c <-- previous %c", sm_runlevel(runlevel), sm_runlevel(prevlevel));
+		dbg("Setting new runlevel --> %c <-- previous %c", sm_rl2ch(runlevel), sm_rl2ch(prevlevel));
 		if (osheading)
-			logit(LOG_CONSOLE | LOG_NOTICE, "%s, entering runlevel %c", osheading, sm_runlevel(runlevel));
+			logit(LOG_CONSOLE | LOG_NOTICE, "%s, entering runlevel %c", osheading, sm_rl2ch(runlevel));
 		else
-			logit(LOG_CONSOLE | LOG_NOTICE, "Entering runlevel %c", sm_runlevel(runlevel));
+			logit(LOG_CONSOLE | LOG_NOTICE, "Entering runlevel %c", sm_rl2ch(runlevel));
 		runlevel_set(prevlevel, runlevel);
 
 		/* Disable login in single-user mode as well as shutdown/reboot */
@@ -302,10 +298,10 @@ restart:
 		service_runtask_clean();
 
 		dbg("Stopping services not allowed in new runlevel ...");
-		sm->in_teardown = 1;
+		sm.in_reload = 1;
 		service_step_all(SVC_TYPE_ANY);
 
-		sm->state = SM_RUNLEVEL_WAIT_STATE;
+		sm.state = SM_RUNLEVEL_WAIT_STATE;
 		break;
 
 	case SM_RUNLEVEL_WAIT_STATE:
@@ -324,10 +320,10 @@ restart:
 		plugin_run_hooks(HOOK_RUNLEVEL_CHANGE);  /* Reconfigure HW/VLANs/etc here */
 
 		dbg("Starting services new to this runlevel ...");
-		sm->in_teardown = 0;
+		sm.in_reload = 0;
 		service_step_all(SVC_TYPE_ANY);
 
-		sm->state = SM_RUNLEVEL_CLEAN_STATE;
+		sm.state = SM_RUNLEVEL_CLEAN_STATE;
 		break;
 
 	case SM_RUNLEVEL_CLEAN_STATE:
@@ -361,7 +357,7 @@ restart:
 		if (runlevel == 0 || runlevel == 6)
 			do_shutdown(halt);
 
-		sm->state = SM_RUNNING_STATE;
+		sm.state = SM_RUNNING_STATE;
 		break;
 
 	case SM_RELOAD_CHANGE_STATE:
@@ -373,11 +369,11 @@ restart:
 		 * let all affected services move to WAITING/HALTED
 		 */
 		dbg("Stopping services not allowed after reconf ...");
-		sm->in_teardown = 1;
+		sm.in_reload = 1;
 		cond_reload();
 		service_step_all(SVC_TYPE_ANY);
 
-		sm->state = SM_RELOAD_WAIT_STATE;
+		sm.state = SM_RELOAD_WAIT_STATE;
 		break;
 
 	case SM_RELOAD_WAIT_STATE:
@@ -391,12 +387,12 @@ restart:
 			break;
 		}
 
-		sm->in_teardown = 0;
+		sm.in_reload = 0;
 
 		dbg("Starting services after reconf ...");
 		service_step_all(SVC_TYPE_ANY);
 
-		sm->state = SM_RELOAD_CLEAN_STATE;
+		sm.state = SM_RELOAD_CLEAN_STATE;
 		break;
 
 	case SM_RELOAD_CLEAN_STATE:
@@ -422,14 +418,66 @@ restart:
 		service_notify_reconf();
 
 		dbg("Reconfiguration done");
-		sm->state = SM_RUNNING_STATE;
+		sm.state = SM_RUNNING_STATE;
 		break;
 	}
 
-	if (sm->state != old_state)
+	if (sm.state != old_state)
 		goto restart;
 }
 
+/**
+ * sm_in_reload - System currently in reload or runlevel change?
+ *
+ * Returns:
+ * %TRUE(1) or %FALSE(0)
+ */
+int sm_in_reload(void)
+{
+	return sm.in_reload;
+}
+
+/**
+ * sm_reload - Called on SIGHUP, 'init q' or 'initctl reload'
+ *
+ * This function is called when Finit has received SIGHUP to reload
+ * .conf files in /etc/finit.d.  It is responsible for starting,
+ * stopping and reloading (forwarding SIGHUP) to processes affected.
+ */
+void sm_reload(void)
+{
+	sm.reload = 1;
+
+	dbg("Flushing pending .conf file events ...");
+	conf_flush_events();
+
+	sm_step();
+}
+
+/**
+ * sm_runlevel - Change to a new runlevel
+ * @newlevel: New runlevel to activate
+ *
+ * Stops all services not in @newlevel and starts, or lets continue to run,
+ * those in @newlevel.  Also updates @prevlevel and active @runlevel.
+ */
+void sm_runlevel(int newlevel)
+{
+	if (!rescue && (runlevel == 1 || runlevel == INIT_LEVEL) && !IS_RESERVED_RUNLEVEL(newlevel))
+		networking(1);
+
+	sm.newlevel = newlevel;
+
+	dbg("Flushing pending .conf file events ...");
+	conf_flush_events();
+
+	sm_step();
+
+	if (!rescue && IS_RESERVED_RUNLEVEL(runlevel))
+		networking(0);
+}
+
+
 /**
  * Local Variables:
  *  indent-tabs-mode: t

src/sm.h

@@ -24,32 +24,12 @@
 #ifndef FINIT_SM_H_
 #define FINIT_SM_H_
 
-typedef enum {
+void sm_init      (void);
-	SM_BOOTSTRAP_STATE = 0,   /* Init state, bootstrap services */
+void sm_step      (void);
-	SM_BOOTSTRAP_WAIT_STATE,  /* Waiting for bootstrap to complete */
-	SM_RUNNING_STATE,         /* Normal state, services running */
-	SM_RUNLEVEL_CHANGE_STATE, /* A runlevel change has occurred */
-	SM_RUNLEVEL_WAIT_STATE,   /* Waiting for all stopped processes to halt */
-	SM_RUNLEVEL_CLEAN_STATE,  /* Wait for post:scripts and cleanup:scripts */
-	SM_RELOAD_CHANGE_STATE,   /* A reload event has occurred */
-	SM_RELOAD_WAIT_STATE,     /* Waiting for all stopped processes to halt */
-	SM_RELOAD_CLEAN_STATE,    /* Wait for post:scripts and cleanup:scripts */
-} sm_state_t;
 
-typedef struct sm {
+int  sm_in_reload (void);
-	sm_state_t state;         /* Running, Changed, Waiting, ... */
+void sm_reload    (void);
-	int newlevel;             /* Set on runlevel change to new runlevel, -1 if not change */
+void sm_runlevel  (int newlevel);
-	int reload;               /* Set on reload event, else 0  */
-	int in_teardown;          /* Set when waiting for all processes to be halted */
-} sm_t;
-
-extern sm_t  sm;
-
-void sm_init(sm_t *sm);
-void sm_step(sm_t *sm);
-void sm_set_runlevel(sm_t *sm, int newlevel);
-void sm_set_reload(sm_t *sm);
-int  sm_is_in_teardown(sm_t *sm);
 
 #endif	/* FINIT_SM_H_ */