[RFC 2/2] testpmd: cleanup cleanly from signal

[Stephen Hemminger <stephen@networkplumber.org>]

The original behavior of testpmd was to kill itself when
it received a SIGINT or SIGTERM. This makes it hard to use
testpmd in test automation where forwarding loop is started
and then stopped via SIGTERM.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 app/test-pmd/testpmd.c | 76 +++++++++++++++++++++++++-----------------
 1 file changed, 46 insertions(+), 30 deletions(-)

diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c
index 815dd6dab4e3..8c19ded1655e 100644
--- a/app/test-pmd/testpmd.c
+++ b/app/test-pmd/testpmd.c
@@ -15,6 +15,7 @@
 #include <sys/types.h>
 #include <errno.h>
 #include <stdbool.h>
+#include <poll.h>
 
 #include <sys/queue.h>
 #include <sys/stat.h>
@@ -4243,25 +4244,37 @@ print_stats(void)
 static void
 signal_handler(int signum)
 {
-	if (signum == SIGINT || signum == SIGTERM) {
-		fprintf(stderr, "\nSignal %d received, preparing to exit...\n",
-			signum);
-#ifdef RTE_LIB_PDUMP
-		/* uninitialize packet capture framework */
-		rte_pdump_uninit();
-#endif
-#ifdef RTE_LIB_LATENCYSTATS
-		if (latencystats_enabled != 0)
-			rte_latencystats_uninit();
-#endif
-		force_quit();
-		/* Set flag to indicate the force termination. */
-		f_quit = 1;
-		/* exit with the expected status */
-#ifndef RTE_EXEC_ENV_WINDOWS
-		signal(signum, SIG_DFL);
-		kill(getpid(), signum);
-#endif
+	fprintf(stderr, "\nSignal %d %s received, preparing to exit...\n",
+		signum, strsignal(signum));
+
+	/* Set flag to indicate the force termination. */
+	f_quit = 1;
+}
+
+static int
+wait_for_input(void)
+{
+	struct pollfd pfd = {
+		.fd = STDIN_FILENO,
+		.events =  POLLIN,
+	};
+	char c;
+
+	printf("Press enter to exit\n");
+	for (;;) {
+		if (f_quit)
+			return 0;
+
+		if (poll(&pfd, 1, -1) < 0) {
+			if (errno == EINTR)
+				continue;
+			return -1;
+		}
+
+		if (read(STDIN_FILENO, &c, 1) < 0)
+			return -1;
+
+		return 0;
 	}
 }
 
@@ -4441,11 +4454,6 @@ main(int argc, char** argv)
 	} else
 #endif
 	{
-		char c;
-		int rc;
-
-		f_quit = 0;
-
 		printf("No commandline core given, start packet forwarding\n");
 		start_packet_forwarding(tx_first);
 		if (stats_period != 0) {
@@ -4468,15 +4476,23 @@ main(int argc, char** argv)
 				prev_time = cur_time;
 				rte_delay_us_sleep(US_PER_S);
 			}
+		} else {
+			if (wait_for_input() < 0)
+				return 1;
 		}
-
-		printf("Press enter to exit\n");
-		rc = read(0, &c, 1);
-		pmd_test_exit();
-		if (rc < 0)
-			return 1;
+		stop_packet_forwarding();
+		force_quit();
 	}
 
+#ifdef RTE_LIB_PDUMP
+	/* uninitialize packet capture framework */
+	rte_pdump_uninit();
+#endif
+#ifdef RTE_LIB_LATENCYSTATS
+	if (latencystats_enabled != 0)
+		rte_latencystats_uninit();
+#endif
+
 	ret = rte_eal_cleanup();
 	if (ret != 0)
 		rte_exit(EXIT_FAILURE,
-- 
2.35.1