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/*
40 * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
41 * That means, when it wraps around any pid < 300 will be skipped.
42 * So we need to use a pid > 300 in order to test recycling.
43 */
44#define PID_RECYCLE 1000
45
46/*
47 * Define a few custom error codes for the child process to clearly indicate
48 * what is happening. This way we can tell the difference between a system
49 * error, a test error, etc.
50 */
51#define PIDFD_PASS 0
52#define PIDFD_FAIL 1
53#define PIDFD_ERROR 2
54#define PIDFD_SKIP 3
55#define PIDFD_XFAIL 4
56
57int wait_for_pid(pid_t pid)
58{
59 int status, ret;
60
61again:
62 ret = waitpid(pid, &status, 0);
63 if (ret == -1) {
64 if (errno == EINTR)
65 goto again;
66
67 return -1;
68 }
69
70 if (!WIFEXITED(status))
71 return -1;
72
73 return WEXITSTATUS(status);
74}
75
76static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
77{
78 return syscall(__NR_pidfd_open, pid, flags);
79}
80
81static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
82 unsigned int flags)
83{
84 return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
85}
86
87#endif /* __PIDFD_H */