sysmobts-mgr: generate coredump and exit upon SIGABRT received

Previous code relied on abort() switching sigaction to SIG_FDL +
retriggering SIGABRT in case the signal handler returns, which would
then generate the coredump + terminate the process.
However, if a SIGABRT is received from somewhere else (kill -SIGABRT),
then the process would print the talloc report and continue running,
which is not desired.

Change-Id: I35ae930b59c48892e5ad9a2826e05d6c5d415abc
Fixes: OS#4865

1 files changed, 14 insertions, 3 deletions

diff --git a/src/osmo-bts-sysmo/misc/sysmobts_mgr.c b/src/osmo-bts-sysmo/misc/sysmobts_mgr.c
index dc7af3ce..61b08b43 100644
--- a/src/osmo-bts-sysmo/misc/sysmobts_mgr.c
+++ b/src/osmo-bts-sysmo/misc/sysmobts_mgr.c
@@ -192,11 +192,11 @@ static int parse_options(int argc, char **argv)
 	return 0;
 }
 
-static void signal_handler(int signal)
+static void signal_handler(int signum)
 {
-	fprintf(stderr, "signal %u received\n", signal);
+	fprintf(stderr, "signal %u received\n", signum);
 
-	switch (signal) {
+	switch (signum) {
 	case SIGINT:
 	case SIGTERM:
 		sysmobts_check_temp(no_eeprom_write);
@@ -204,6 +204,16 @@ static void signal_handler(int signal)
 		exit(0);
 		break;
 	case SIGABRT:
+		/* in case of abort, we want to obtain a talloc report and
+		 * then run default SIGABRT handler, who will generate coredump
+		 * and abort the process. abort() should do this for us after we
+		 * return, but program wouldn't exit if an external SIGABRT is
+		 * received.
+		 */
+		talloc_report_full(tall_mgr_ctx, stderr);
+		signal(SIGABRT, SIG_DFL);
+		raise(SIGABRT);
+		break;
 	case SIGUSR1:
 	case SIGUSR2:
 		talloc_report_full(tall_mgr_ctx, stderr);
@@ -262,6 +272,7 @@ int main(int argc, char **argv)
 	osmo_init_ignore_signals();
 	signal(SIGINT, &signal_handler);
 	signal(SIGTERM, &signal_handler);
+	signal(SIGABRT, &signal_handler);
 	signal(SIGUSR1, &signal_handler);
 	signal(SIGUSR2, &signal_handler);