unplugged-system/external/ltp/testcases/kernel/syscalls/epoll_ctl/epoll_ctl05.c

72 lines
1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) Linux Test Project, 2021
* Author: Xie Ziyao <ziyaoxie@outlook.com>
*/
/*\
* [Description]
*
* Verify that epoll_ctl() fails with ELOOP if fd refers to an epoll instance
* and this EPOLL_CTL_ADD operation would result in a circular loop of epoll
* instances monitoring one another.
*/
#include <poll.h>
#include <sys/epoll.h>
#include "tst_test.h"
#define MAX_DEPTH 5
static int epfd, origin_epfd, new_epfd;
static int fd[2];
static struct epoll_event events = {.events = EPOLLIN};
static void setup(void)
{
int i;
SAFE_PIPE(fd);
for (i = 0, epfd = fd[0]; i < MAX_DEPTH; i++, epfd = new_epfd) {
new_epfd = epoll_create(1);
if (new_epfd == -1)
tst_brk(TBROK | TERRNO, "fail to create epoll instance");
if (i == 0)
origin_epfd = new_epfd;
events.data.fd = epfd;
if (epoll_ctl(new_epfd, EPOLL_CTL_ADD, epfd, &events))
tst_brk(TBROK | TERRNO, "epoll_clt(..., EPOLL_CTL_ADD, ...)");
}
events.data.fd = fd[0];
if (epoll_ctl(origin_epfd, EPOLL_CTL_DEL, fd[0], &events))
tst_brk(TBROK | TERRNO, "epoll_clt(..., EPOLL_CTL_DEL, ...)");
}
static void cleanup(void)
{
if (fd[0])
SAFE_CLOSE(fd[0]);
if (fd[1])
SAFE_CLOSE(fd[1]);
}
static void verify_epoll_ctl(void)
{
events.data.fd = epfd;
TST_EXP_FAIL(epoll_ctl(origin_epfd, EPOLL_CTL_ADD, epfd, &events),
ELOOP, "epoll_clt(..., EPOLL_CTL_ADD, ...)");
}
static struct tst_test test = {
.setup = setup,
.cleanup = cleanup,
.test_all = verify_epoll_ctl,
};