strace/tests/detach-stopped.test

#!/bin/sh
#
# Ensure that strace can detach from stopped processes.
#
# Copyright (c) 2013-2015 Dmitry V. Levin <ldv@altlinux.org>
# Copyright (c) 2014-2018 The strace developers.
# All rights reserved.
#
# SPDX-License-Identifier: GPL-2.0-or-later

. "${srcdir=.}/init.sh"

run_prog_skip_if_failed \
	kill -0 $$

$STRACE -d -enone / > /dev/null 2> "$LOG"
if grep -x "[^:]*strace: PTRACE_SEIZE doesn't work" "$LOG" > /dev/null; then
	skip_ "PTRACE_SEIZE doesn't work"
fi

check_prog sleep

trap - TERM
sleep $TIMEOUT_DURATION &
kill -TERM $!
wait $!
expected_rc=$?

set -e

> "$LOG"
../set_ptracer_any sleep $((2*$TIMEOUT_DURATION)) > "$LOG" &

while ! [ -s "$LOG" ]; do
	kill -0 $! 2> /dev/null ||
		fail_ 'set_ptracer_any sleep failed'
	$SLEEP_A_BIT
done

tracee_pid=$!
kill -STOP $tracee_pid

cleanup()
{
	set +e
	kill $tracee_pid
	kill -CONT $tracee_pid
	wait $tracee_pid 2> /dev/null
	return 0
}

> "$LOG"
$STRACE -p $tracee_pid 2> "$LOG" &

while ! grep -F "Process $tracee_pid attached" "$LOG" > /dev/null; do
	kill -0 $! 2> /dev/null || {
		cleanup
		dump_log_and_fail_with "$STRACE -p failed to attach"
	}
	$SLEEP_A_BIT
done

while ! grep -F -e '--- stopped by ' "$LOG" > /dev/null; do
	kill -0 $! 2> /dev/null || {
		cleanup
		dump_log_and_fail_with "$STRACE -p missed stop notifications"
	}
	$SLEEP_A_BIT
done

kill -TERM $!
wait $! && rc=0 || rc=$?

grep -F "Process $tracee_pid detached" "$LOG" > /dev/null || {
	cleanup
	dump_log_and_fail_with "$STRACE -p failed to detach"
}

[ "$rc" = "$expected_rc" ] || {
	cleanup
	dump_log_and_fail_with "$STRACE -p failed to terminate itself"
}

if [ -f /proc/self/status ]; then
	$SLEEP_A_BIT
	test -d /proc/$tracee_pid || {
		cleanup
		dump_log_and_fail_with 'tracee died after detach'
	}
	grep_pid_status "$tracee_pid" '^State:.*T (stopped)' > /dev/null || {
		grep_pid_status "$tracee_pid" '^State:'
		cleanup
		dump_log_and_fail_with 'tracee is not group-stopped after detach'
	}
fi

cleanup
exit 0