mobile: Improved exit of mobile process, reset phone

If mobile phone has started, it is reset after shutdown. This
ensures that the phone is not transmitting anymore, especially
while shutting down in dedicated mode.

Using CTRL+c:
The first signal causes initiating of shutdown with detach
procedure. The second signal causes initiating of shutdown
without detach procedure. The third signal will exit process
immidiately. (in case it hangs)

Using CTRL+z:
The first signal causes initiating of shutdown without detach
procedure. A subsequent CTRL+c would exit process immidiately.

3 files changed, 62 insertions, 19 deletions

diff --git a/src/host/layer23/src/mobile/app_mobile.c b/src/host/layer23/src/mobile/app_mobile.c
index dc57c315..67aba05a 100644
--- a/src/host/layer23/src/mobile/app_mobile.c
+++ b/src/host/layer23/src/mobile/app_mobile.c
@@ -93,6 +93,13 @@ int mobile_signal_cb(unsigned int subsys, unsigned int signal,
 		ms = signal_data;
 		set = &ms->settings;
 
+		/* waiting for reset after shutdown */
+		if (ms->shutdown == 2) {
+			printf("MS '%s' has been resetted\n", ms->name);
+			ms->shutdown = 3;
+			break;
+		}
+
 		if (ms->started)
 			break;
 
@@ -129,6 +136,10 @@ int mobile_exit(struct osmocom_ms *ms, int force)
 {
 	struct gsm48_mmlayer *mm = &ms->mmlayer;
 
+	/* if shutdown is already performed */
+	if (ms->shutdown >= 2)
+		return 0;
+
 	if (!force && ms->started) {
 		struct msgb *nmsg;
 
@@ -151,7 +162,12 @@ int mobile_exit(struct osmocom_ms *ms, int force)
 	gsm_sim_exit(ms);
 	lapdm_channel_exit(&ms->lapdm_channel);
 
-	ms->shutdown = 2; /* being down */
+	if (ms->started) {
+		ms->shutdown = 2; /* being down, wait for reset */
+		l1ctl_tx_reset_req(ms, L1CTL_RES_T_FULL);
+	} else {
+		ms->shutdown = 3; /* being down */
+	}
 	vty_notify(ms, NULL);
 	vty_notify(ms, "Power off!\n");
 	printf("Power off! (MS %s)\n", ms->name);
@@ -241,7 +257,7 @@ struct osmocom_ms *mobile_new(char *name)
 	gsm_support_init(ms);
 	gsm_settings_init(ms);
 
-	ms->shutdown = 2; /* being down */
+	ms->shutdown = 3; /* being down */
 
 	if (mncc_recv_app) {
 		char name[32];
@@ -292,10 +308,14 @@ int global_signal_cb(unsigned int subsys, unsigned int signal,
 
 	switch (signal) {
 	case S_GLOBAL_SHUTDOWN:
+		/* force to exit, if signalled */
+		if (signal_data && *((uint8_t *)signal_data))
+			quit = 1;
+
 		llist_for_each_entry_safe(ms, ms2, &ms_list, entity)
 			mobile_delete(ms, quit);
 
-		/* if second signal is received, force to exit */
+		/* quit, after all MS processes are gone */
 		quit = 1;
 		break;
 	}
@@ -309,9 +329,9 @@ int l23_app_work(int *_quit)
 	int work = 0;
 
 	llist_for_each_entry_safe(ms, ms2, &ms_list, entity) {
-		if (ms->shutdown != 2)
+		if (ms->shutdown != 3)
 			work |= mobile_work(ms);
-		if (ms->shutdown == 2) {
+		if (ms->shutdown == 3) {
 			if (ms->l2_wq.bfd.fd > -1) {
 				layer2_close(ms);
 				ms->l2_wq.bfd.fd = -1;
diff --git a/src/host/layer23/src/mobile/main.c b/src/host/layer23/src/mobile/main.c
index 312bcd66..8bcecba3 100644
--- a/src/host/layer23/src/mobile/main.c
+++ b/src/host/layer23/src/mobile/main.c
@@ -153,25 +153,38 @@ static void handle_options(int argc, char **argv)
 
 void sighandler(int sigset)
 {
+	static uint8_t _quit = 1, count_int = 0;
+
 	if (sigset == SIGHUP || sigset == SIGPIPE)
 		return;
 
-	fprintf(stderr, "Signal %d received.\n", sigset);
+	fprintf(stderr, "\nSignal %d received.\n", sigset);
 
 	switch (sigset) {
 	case SIGINT:
-		/* If another signal is received afterwards, the program
-		 * is terminated without finishing shutdown process.
+		/* The first signal causes initiating of shutdown with detach
+		 * procedure. The second signal causes initiating of shutdown
+		 * without detach procedure. The third signal will exit process
+		 * immidiately. (in case it hangs)
 		 */
-		signal(SIGINT, SIG_DFL);
-		signal(SIGHUP, SIG_DFL);
-		signal(SIGTERM, SIG_DFL);
-		signal(SIGPIPE, SIG_DFL);
-		signal(SIGABRT, SIG_DFL);
-		signal(SIGUSR1, SIG_DFL);
-		signal(SIGUSR2, SIG_DFL);
-
-		osmo_signal_dispatch(SS_GLOBAL, S_GLOBAL_SHUTDOWN, NULL);
+		if (count_int == 0) {
+			fprintf(stderr, "Performing shutdown with clean "
+				"detach, if possible...\n");
+			osmo_signal_dispatch(SS_GLOBAL, S_GLOBAL_SHUTDOWN,
+				NULL);
+			count_int = 1;
+			break;
+		}
+		if (count_int == 2) {
+			fprintf(stderr, "Unclean exit, please turn off phone "
+				"to be sure it is not transmitting!\n");
+			exit(0);
+		}
+		/* fall through */
+	case SIGTSTP:
+		count_int = 2;
+		fprintf(stderr, "Performing shutdown without detach...\n");
+		osmo_signal_dispatch(SS_GLOBAL, S_GLOBAL_SHUTDOWN, &_quit);
 		break;
 	case SIGABRT:
 		/* in case of abort, we want to obtain a talloc report
@@ -240,6 +253,7 @@ int main(int argc, char **argv)
 		exit(rc);
 
 	signal(SIGINT, sighandler);
+	signal(SIGTSTP, sighandler);
 	signal(SIGHUP, sighandler);
 	signal(SIGTERM, sighandler);
 	signal(SIGPIPE, sighandler);
@@ -267,5 +281,14 @@ int main(int argc, char **argv)
 	talloc_free(config_dir);
 	talloc_report_full(l23_ctx, stderr);
 
+	signal(SIGINT, SIG_DFL);
+	signal(SIGTSTP, SIG_DFL);
+	signal(SIGHUP, SIG_DFL);
+	signal(SIGTERM, SIG_DFL);
+	signal(SIGPIPE, SIG_DFL);
+	signal(SIGABRT, SIG_DFL);
+	signal(SIGUSR1, SIG_DFL);
+	signal(SIGUSR2, SIG_DFL);
+
 	return 0;
 }
diff --git a/src/host/layer23/src/mobile/vty_interface.c b/src/host/layer23/src/mobile/vty_interface.c
index 4d7f6a27..95653c78 100644
--- a/src/host/layer23/src/mobile/vty_interface.c
+++ b/src/host/layer23/src/mobile/vty_interface.c
@@ -2607,11 +2607,11 @@ DEFUN(cfg_no_shutdown, cfg_ms_no_shutdown_cmd, "no shutdown",
 	struct osmocom_ms *ms = vty->index, *tmp;
 	int rc;
 
-	if (ms->shutdown != 2)
+	if (ms->shutdown != 3)
 		return CMD_SUCCESS;
 
 	llist_for_each_entry(tmp, &ms_list, entity) {
-		if (tmp->shutdown == 2)
+		if (tmp->shutdown == 3)
 			continue;
 		if (!strcmp(ms->settings.layer2_socket_path,
 				tmp->settings.layer2_socket_path)) {