Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2
3#ifndef __PIDFD_H
4#define __PIDFD_H
5
6#define _GNU_SOURCE
7#include <errno.h>
8#include <fcntl.h>
9#include <sched.h>
10#include <signal.h>
11#include <stdio.h>
12#include <stdlib.h>
13#include <string.h>
14#include <syscall.h>
15#include <sys/mount.h>
16
17#include "../kselftest.h"
18
19#ifndef P_PIDFD
20#define P_PIDFD 3
21#endif
22
23#ifndef CLONE_PIDFD
24#define CLONE_PIDFD 0x00001000
25#endif
26
27#ifndef __NR_pidfd_open
28#define __NR_pidfd_open -1
29#endif
30
31#ifndef __NR_pidfd_send_signal
32#define __NR_pidfd_send_signal -1
33#endif
34
35#ifndef __NR_clone3
36#define __NR_clone3 -1
37#endif
38
39#ifndef __NR_pidfd_getfd
40#define __NR_pidfd_getfd -1
41#endif
42
43/*
44 * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
45 * That means, when it wraps around any pid < 300 will be skipped.
46 * So we need to use a pid > 300 in order to test recycling.
47 */
48#define PID_RECYCLE 1000
49
50/*
51 * Define a few custom error codes for the child process to clearly indicate
52 * what is happening. This way we can tell the difference between a system
53 * error, a test error, etc.
54 */
55#define PIDFD_PASS 0
56#define PIDFD_FAIL 1
57#define PIDFD_ERROR 2
58#define PIDFD_SKIP 3
59#define PIDFD_XFAIL 4
60
61int wait_for_pid(pid_t pid)
62{
63 int status, ret;
64
65again:
66 ret = waitpid(pid, &status, 0);
67 if (ret == -1) {
68 if (errno == EINTR)
69 goto again;
70
71 return -1;
72 }
73
74 if (!WIFEXITED(status))
75 return -1;
76
77 return WEXITSTATUS(status);
78}
79
80static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
81{
82 return syscall(__NR_pidfd_open, pid, flags);
83}
84
85static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
86 unsigned int flags)
87{
88 return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
89}
90
91static inline int sys_pidfd_getfd(int pidfd, int fd, int flags)
92{
93 return syscall(__NR_pidfd_getfd, pidfd, fd, flags);
94}
95
96#endif /* __PIDFD_H */