tests/init.sh: check for successful run under strace in run_prog

In some environments it's possible that syscalls behave differently when
the process is being ptrace'd.

* tests/init.sh (run_prog): Move down, rewrite using try_run_prog, add
a check for successful execution of the program under strace in the
"medicinal mode" (-qq -enone -esignal=none -o /dev/null).

tests/init.sh

@@ -50,23 +50,6 @@ dump_log_and_fail_with()
 	fail_ "$*"
 }
 
-run_prog()
-{
-	if [ $# -eq 0 ]; then
-		set -- "../$NAME"
-	fi
-	args="$*"
-	"$@" || {
-		rc=$?
-		if [ $rc -eq 77 ]; then
-			skip_ "$args exited with code 77"
-		else
-			fail_ "$args failed with code $rc"
-		fi
-	}
-}
-
-
 run_prog_skip_if_failed()
 {
 	args="$*"
@@ -87,6 +70,22 @@ try_run_prog()
 	}
 }
 
+run_prog()
+{
+	if [ $# -eq 0 ]; then
+		set -- "../$NAME"
+	fi
+	args="$*"
+	# We try to run under strace since there could be some security policies
+	# or seccomp filters in place that change behaviour of various syscalls
+	# when a process is being traced
+
+	try_run_prog "$@" || skip_ "$args exited with code 77"
+	try_run_prog $STRACE -o /dev/null -qq -enone -esignal=none "$@" ||
+		skip_ "$STRACE -o /dev/null -qq -enone -esignal=none $args" \
+		      "exited with code 77"
+}
+
 run_strace()
 {
 	> "$LOG" || fail_ "failed to write $LOG"