test: new test, verify SysV start/stop daemon support

Install start-stop-daemon in test root.  Add S01-service.sh, which uses
start-stop-daemon to start service.sh.  Modify service.sh to respect
signals, and not exit immediately when sleep exits due to SIGTERM.
Remove PID file in signal callback and make sure to exit OK

The test itself is basically a copy of the start-stop-service.sh test.

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

test/common/S01-service.sh

@@ -0,0 +1,43 @@
+#!/bin/sh
+# SysV style start script for service.sh
+
+DAEMON="/test_assets/service.sh"
+PIDFILE="/var/run/service.pid"
+
+start() {
+	printf 'Starting %s: ' "$DAEMON"
+	start-stop-daemon -S -b -q -p "$PIDFILE" -x "$DAEMON"
+	status=$?
+	if [ "$status" -eq 0 ]; then
+		echo "OK"
+	else
+		echo "FAIL"
+	fi
+	return "$status"
+}
+
+stop() {
+	printf 'Stopping %s: ' "$DAEMON"
+	start-stop-daemon -K -q -p "$PIDFILE"
+	status=$?
+	if [ "$status" -eq 0 ]; then
+		echo "OK"
+	else
+		echo "FAIL"
+	fi
+	return "$status"
+}
+
+restart() {
+	stop
+	sleep 1
+	start
+}
+
+case "$1" in
+	start|stop|restart)
+		"$1";;
+	*)
+		echo "Usage: $0 {start|stop|restart}, got $0 $1"
+		exit 1
+esac

test/common/service.sh

@@ -1,15 +1,24 @@
 #!/bin/sh
 
-set -eu
+cleanup()
+{
+  echo "Got signal, stopping ..."
+  rm -f /run/service.pid
+  exit 0
+}
 
 # Hook SIGUSR1 and dump trace to file system
 # shellcheck disable=SC2172
-trap 'echo USR1 > /tmp/usr1.log' 10
+trap 'echo USR1 > /tmp/usr1.log' USR1
+trap cleanup INT
+trap cleanup TERM
+trap cleanup QUIT
+trap cleanup EXIT
 
 echo $$ > /run/service.pid
 
+# sleep may exit on known signal, so
+# we cannot use 'set -e'
 while true; do
-  sleep 5
+  sleep 1
 done
-
-rm /run/service.pid