misc: Add an option exit/quit when the BSSGP is supposed to be destroyed

The PCU does not properly re-set the state when the connection to the
BTS is lost (and the SGSN potentially is re-started during that). This
results in the BSSGP BVCI > 1 remaining blocked and no data will be
accepted by the SGSN.

Add the '-e' option and exit the PCU when the BSSGP/NS are getting
destroyed.

src/gprs_bssgp_pcu.cpp

@@ -27,6 +27,7 @@ struct bssgp_bvc_ctx *bctx = NULL;
 struct gprs_nsvc *nsvc = NULL;
 static int bvc_sig_reset = 0, bvc_reset = 0, bvc_unblocked = 0;
 extern uint16_t spoof_mcc, spoof_mnc;
+static int exit_on_destroy = 0;
 
 struct osmo_timer_list bvc_timer;
 
@@ -640,8 +641,13 @@ int gprs_bssgp_create(uint16_t local_port, uint32_t sgsn_ip,
 	return 0;
 }
 
-void gprs_bssgp_destroy(void)
+void gprs_bssgp_destroy_or_exit(void)
 {
+	if (exit_on_destroy) {
+		LOGP(DBSSGP, LOGL_NOTICE, "Exiting on BSSGP destruction.\n");
+		exit(0);
+	}
+
 	if (!bssgp_nsi)
 		return;
 
@@ -662,3 +668,8 @@ void gprs_bssgp_destroy(void)
 	bssgp_nsi = NULL;
 }
 
+void gprs_bssgp_exit_on_destroy(void)
+{
+	LOGP(DBSSGP, LOGL_NOTICE, "Going to quit on BSSGP destruction\n");
+	exit_on_destroy = 1;
+}

src/gprs_bssgp_pcu.h

@@ -56,6 +56,7 @@ int gprs_bssgp_create(uint16_t local_port, uint32_t sgsn_ip, uint16_t
 		uint16_t mcc, uint16_t mnc, uint16_t lac, uint16_t rac,
 		uint16_t cell_id);
 
-void gprs_bssgp_destroy(void);
+void gprs_bssgp_exit_on_destroy(void);
+void gprs_bssgp_destroy_or_exit(void);
 
 #endif // GPRS_BSSGP_PCU_H

src/openbts_sock.cpp

@@ -179,7 +179,7 @@ int pcu_l1if_open()
 
 void pcu_l1if_close(void)
 {
-	gprs_bssgp_destroy();
+	gprs_bssgp_destroy_or_exit();
 
 	/* FIXME: cleanup l1if */
 	talloc_free(l1fh->fl1h);

src/pcu_l1_if.cpp

@@ -369,7 +369,7 @@ bssgp_failed:
 						trx, ts);
 			}
 		}
-		gprs_bssgp_destroy();
+		gprs_bssgp_destroy_or_exit();
 		return 0;
 	}
 	LOGP(DL1IF, LOGL_INFO, "BTS available\n");

src/pcu_main.cpp

@@ -60,6 +60,7 @@ static void print_help()
 			"provided by BTS\n"
 		"  -r   --realtime PRIO Use SCHED_RR with the specified "
 			"priority\n"
+		"  -e   --exit		Exit the application on disconnect\n"
 		);
 }
 
@@ -75,10 +76,11 @@ static void handle_options(int argc, char **argv)
 			{ "mnc", 1, 0, 'n' },
 			{ "version", 0, 0, 'V' },
 			{ "realtime", 1, 0, 'r' },
+			{ "exit", 0, 0, 'e' },
 			{ 0, 0, 0, 0 }
 		};
 
-		c = getopt_long(argc, argv, "hc:m:n:Vr:",
+		c = getopt_long(argc, argv, "hc:m:n:Vr:e",
 				long_options, &option_idx);
 		if (c == -1)
 			break;
@@ -105,6 +107,9 @@ static void handle_options(int argc, char **argv)
 		case 'r':
 			rt_prio = atoi(optarg);
 			break;
+		case 'e':
+			gprs_bssgp_exit_on_destroy();
+			break;
 		default:
 			fprintf(stderr, "Unknown option '%c'\n", c);
 			exit(0);

src/sysmo_sock.cpp

@@ -117,7 +117,7 @@ static void pcu_sock_close(struct pcu_sock_state *state, int lost)
 		}
 	}
 
-	gprs_bssgp_destroy();
+	gprs_bssgp_destroy_or_exit();
 
 	if (lost) {
 		state->timer.cb = pcu_sock_timeout;