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/*
* Copyright (c) 2015-2021 Dmitry V. Levin <ldv@strace.io>
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "tests.h"
#include <assert.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/wait.h>
static int
logit_(const char *const str)
{
return !chdir(str);
}
#define prefix "vfork-f."
#define logit(arg) logit_(prefix arg)
int main(int ac, char **av)
{
if (ac < 1)
return 1;
if (ac > 1) {
if (read(0, &ac, sizeof(int)))
return 2;
return logit("exec");
}
logit("start");
int child_wait_fds[2];
(void) close(0);
if (pipe(child_wait_fds))
perror_msg_and_fail("pipe");
if (fcntl(child_wait_fds[1], F_SETFD, FD_CLOEXEC))
perror_msg_and_fail("fcntl");
int parent_wait_fds[2];
if (pipe(parent_wait_fds))
perror_msg_and_fail("pipe");
if (fcntl(parent_wait_fds[0], F_SETFD, FD_CLOEXEC))
perror_msg_and_fail("fcntl");
if (fcntl(parent_wait_fds[1], F_SETFD, FD_CLOEXEC))
perror_msg_and_fail("fcntl");
char *const args[] = { av[0], (char *) "", NULL };
pid_t pid = vfork();
if (pid < 0)
perror_msg_and_fail("vfork");
if (!pid) {
if (logit("child") || execve(args[0], args, args + 1))
_exit(2);
}
close(0);
close(parent_wait_fds[1]);
if (read(parent_wait_fds[0], &parent_wait_fds[1], sizeof(int)))
perror_msg_and_fail("read");
logit("parent");
close(child_wait_fds[1]);
int status;
assert(wait(&status) == pid);
assert(status == 0);
pid_t ppid = getpid();
logit("finish");
printf("%-5d chdir(\"%sstart\") = -1 ENOENT (%m)\n"
"%-5d chdir(\"%schild\") = -1 ENOENT (%m)\n"
"%-5d chdir(\"%sparent\") = -1 ENOENT (%m)\n"
"%-5d chdir(\"%sexec\") = -1 ENOENT (%m)\n"
"%-5d chdir(\"%sfinish\") = -1 ENOENT (%m)\n",
ppid, prefix,
pid, prefix,
ppid, prefix,
pid, prefix,
ppid, prefix);
return 0;
}
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