// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) Wipro Technologies Ltd, 2002.  All Rights Reserved.
 * Copyright (c) 2019 Jorik Cronenberg <jcronenberg@suse.de>
 *
 * Author: Saji Kumar.V.R <saji.kumar@wipro.com>
 * Ported to new library: Jorik Cronenberg <jcronenberg@suse.de>
 *
 * Test the functionality of ptrace() for PTRACE_TRACEME & PTRACE_KILL requests.
 * Forked child does ptrace(PTRACE_TRACEME, ...).
 * Then a signal is delivered to the child and verified that parent
 * is notified via wait().
 * After parent does ptrace(PTRACE_KILL, ..) to kill the child
 * and parent wait() for child to finish.
 * Test passes if child finished abnormally.
 *
 * Testing two cases:
 * 1) child ignore SIGUSR2 signal
 * 2) using a signal handler for child for SIGUSR2
 * In both cases, child should stop & notify parent on reception of SIGUSR2.
 */

#include <stdlib.h>
#include <errno.h>
#include <signal.h>
#include <sys/wait.h>
#include <config.h>
#include "ptrace.h"
#include "tst_test.h"

static volatile int got_signal;

static void child_handler(int sig LTP_ATTRIBUTE_UNUSED)
{
	SAFE_KILL(getppid(), SIGUSR2);
}

static void parent_handler(int sig LTP_ATTRIBUTE_UNUSED)
{
	got_signal = 1;
}

static void do_child(unsigned int i)
{
	struct sigaction child_act;

	if (i == 0)
		child_act.sa_handler = SIG_IGN;
	else
		child_act.sa_handler = child_handler;

	child_act.sa_flags = SA_RESTART;
	sigemptyset(&child_act.sa_mask);

	SAFE_SIGACTION(SIGUSR2, &child_act, NULL);

	if ((ptrace(PTRACE_TRACEME, 0, 0, 0)) == -1) {
		tst_res(TWARN, "ptrace() failed in child");
		exit(1);
	}
	SAFE_KILL(getpid(), SIGUSR2);
	exit(1);
}

static void run(unsigned int i)
{
	pid_t child_pid;
	int status;
	struct sigaction parent_act;

	got_signal = 0;

	if (i == 1) {
		parent_act.sa_handler = parent_handler;
		parent_act.sa_flags = SA_RESTART;
		sigemptyset(&parent_act.sa_mask);
		SAFE_SIGACTION(SIGUSR2, &parent_act, NULL);
	}

	child_pid = SAFE_FORK();

	if (!child_pid)
		do_child(i);

	SAFE_WAITPID(child_pid, &status, 0);

	if (((WIFEXITED(status)) && (WEXITSTATUS(status)))
		 || (got_signal == 1))
		tst_res(TFAIL, "Test Failed");
	else if ((ptrace(PTRACE_KILL, child_pid, 0, 0)) == -1)
		tst_res(TFAIL | TERRNO, "ptrace(PTRACE_KILL, %i, 0, 0) failed",
				child_pid);

	SAFE_WAITPID(child_pid, &status, 0);

	if (WTERMSIG(status) == 9)
		tst_res(TPASS, "Child %s as expected", tst_strstatus(status));
	else
		tst_res(TFAIL, "Child %s unexpectedly", tst_strstatus(status));

}

static struct tst_test test = {
	.test = run,
	.tcnt = 2,
	.forks_child = 1,
};