int child_func(void *arg)
{
int ret = 0;
/* makes mount DIRA a slave of DIRA (all slave mounts have
* a master mount which is a shared mount) */
if (mount("none", DIRA, "none", MS_SLAVE, NULL) == -1) {
perror("mount");
return 1;
}
TST_CHECKPOINT_SIGNAL_PARENT(&checkpoint1);
TST_CHECKPOINT_CHILD_WAIT(&checkpoint2);
/* checks that shared mounts propagates to slave mount */
if (access(DIRA"/B", F_OK) == -1)
ret = 2;
TST_CHECKPOINT_SIGNAL_PARENT(&checkpoint1);
TST_CHECKPOINT_CHILD_WAIT(&checkpoint2);
/* bind mounts DIRB to DIRA making contents of DIRB visible
* in DIRA */
if (mount(DIRB, DIRA, "none", MS_BIND, NULL) == -1) {
perror("mount");
return 1;
}
TST_CHECKPOINT_SIGNAL_PARENT(&checkpoint1);
TST_CHECKPOINT_CHILD_WAIT(&checkpoint2);
umount(DIRA);
return ret;
}
int main(void)
{
int pid;
struct tst_checkpoint checkpoint;
tst_tmpdir();
TST_CHECKPOINT_CREATE(&checkpoint);
pid = fork();
switch (pid) {
case -1:
tst_brkm(TBROK | TERRNO, NULL, "Fork failed");
break;
case 0:
TST_CHECKPOINT_CHILD_WAIT(&checkpoint);
fprintf(stderr, "Child: checkpoint reached\n");
exit(0);
break;
default:
fprintf(stderr, "Parent: exiting without signaling\n");
tst_rmdir();
exit(0);
break;
}
return 0;
}
static void do_child(void)
{
if (setsid() < 0) {
printf("CHILD: setsid() failed, errno: %d\n", errno);
exit(2);
}
TST_CHECKPOINT_SIGNAL_PARENT(&checkpoint);
TST_CHECKPOINT_CHILD_WAIT(&checkpoint);
exit(0);
}
static void childfunc(int fd)
{
int fd2;
TST_CHECKPOINT_CHILD_WAIT(&checkpoint);
fd2 = open(FILE_NAME, O_RDWR);
if (fd2 == -1) {
fprintf(stderr, "CHILD: failed to open the file: %s\n",
strerror(errno));
exit(1);
}
if (flock(fd2, LOCK_EX | LOCK_NB) != -1) {
fprintf(stderr, "CHILD: The file was not already locked\n");
exit(1);
}
TEST(flock(fd, LOCK_UN));
/* XXX: LOCK_UN does not return an error if there was nothing to
* unlock.
*/
if (TEST_RETURN == -1) {
fprintf(stderr, "CHILD: Unable to unlock file locked by "
"parent: %s\n", strerror(TEST_ERRNO));
exit(1);
} else {
fprintf(stderr, "CHILD: File locked by parent unlocked\n");
}
TEST(flock(fd2, LOCK_EX | LOCK_NB));
if (TEST_RETURN == -1) {
fprintf(stderr, "CHILD: Unable to lock file after "
"unlocking: %s\n", strerror(TEST_ERRNO));
exit(1);
} else {
fprintf(stderr, "CHILD: Locking after unlock passed\n");
}
close(fd);
close(fd2);
exit(0);
}
