98 lines
2.0 KiB
C
98 lines
2.0 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Copyright (c) International Business Machines Corp., 2002
|
|
* Author: Cyril Hrubis
|
|
*
|
|
* Test Description:
|
|
* This test verifies that flock() cannot unlock a file locked by another
|
|
* task.
|
|
*
|
|
* Test Steps:
|
|
* Fork a child processes The parent flocks a file with LOCK_EX Child waits
|
|
* for that to happen, then checks to make sure it is locked. Child then
|
|
* tries to unlock the file. If the unlock succeeds, the child attempts to
|
|
* lock the file with LOCK_EX. The test passes if the child is able to lock
|
|
* the file.
|
|
*/
|
|
|
|
#include <errno.h>
|
|
#include <stdlib.h>
|
|
#include <sys/file.h>
|
|
|
|
#include "tst_test.h"
|
|
|
|
static void childfunc(int fd)
|
|
{
|
|
int fd2;
|
|
TST_CHECKPOINT_WAIT(0);
|
|
|
|
fd2 = SAFE_OPEN("testfile", O_RDWR);
|
|
if (flock(fd2, LOCK_EX | LOCK_NB) != -1)
|
|
tst_brk(TBROK, "CHILD: The file was not already locked");
|
|
|
|
TEST(flock(fd, LOCK_UN));
|
|
if (TST_RET == -1) {
|
|
tst_res(TFAIL, "CHILD: Unable to unlock file locked by "
|
|
"parent: %s", tst_strerrno(TST_ERR));
|
|
exit(1);
|
|
} else {
|
|
tst_res(TPASS, "CHILD: File locked by parent unlocked");
|
|
}
|
|
|
|
TEST(flock(fd2, LOCK_EX | LOCK_NB));
|
|
if (TST_RET == -1) {
|
|
tst_res(TFAIL, "CHILD: Unable to unlock file after "
|
|
"unlocking: %s", tst_strerrno(TST_ERR));
|
|
exit(1);
|
|
} else {
|
|
tst_res(TPASS, "Locking after unlock passed");
|
|
}
|
|
|
|
SAFE_CLOSE(fd);
|
|
SAFE_CLOSE(fd2);
|
|
|
|
exit(0);
|
|
}
|
|
|
|
static void verify_flock(void)
|
|
{
|
|
int fd1;
|
|
pid_t pid;
|
|
|
|
fd1 = SAFE_OPEN("testfile", O_RDWR);
|
|
|
|
pid = SAFE_FORK();
|
|
if (pid == 0)
|
|
childfunc(fd1);
|
|
|
|
TEST(flock(fd1, LOCK_EX | LOCK_NB));
|
|
if (TST_RET != 0) {
|
|
tst_res(TFAIL | TTERRNO,
|
|
"Parent: Initial attempt to flock() failed");
|
|
} else {
|
|
tst_res(TPASS,
|
|
"Parent: Initial attempt to flock() passed");
|
|
}
|
|
|
|
TST_CHECKPOINT_WAKE(0);
|
|
|
|
tst_reap_children();
|
|
|
|
SAFE_CLOSE(fd1);
|
|
}
|
|
|
|
static void setup(void)
|
|
{
|
|
int fd;
|
|
|
|
fd = SAFE_OPEN("testfile", O_CREAT | O_TRUNC | O_RDWR, 0666);
|
|
SAFE_CLOSE(fd);
|
|
}
|
|
|
|
static struct tst_test test = {
|
|
.test_all = verify_flock,
|
|
.needs_checkpoints = 1,
|
|
.forks_child = 1,
|
|
.setup = setup,
|
|
};
|