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#include <sys/types.h>
17#include <sys/wait.h>
18
19#include "../kselftest.h"
20
21#ifndef P_PIDFD
22#define P_PIDFD 3
23#endif
24
25#ifndef CLONE_NEWTIME
26#define CLONE_NEWTIME 0x00000080
27#endif
28
29#ifndef CLONE_PIDFD
30#define CLONE_PIDFD 0x00001000
31#endif
32
33#ifndef __NR_pidfd_open
34#define __NR_pidfd_open -1
35#endif
36
37#ifndef __NR_pidfd_send_signal
38#define __NR_pidfd_send_signal -1
39#endif
40
41#ifndef __NR_clone3
42#define __NR_clone3 -1
43#endif
44
45#ifndef __NR_pidfd_getfd
46#define __NR_pidfd_getfd -1
47#endif
48
49#ifndef PIDFD_NONBLOCK
50#define PIDFD_NONBLOCK O_NONBLOCK
51#endif
52
53/*
54 * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
55 * That means, when it wraps around any pid < 300 will be skipped.
56 * So we need to use a pid > 300 in order to test recycling.
57 */
58#define PID_RECYCLE 1000
59
60/*
61 * Define a few custom error codes for the child process to clearly indicate
62 * what is happening. This way we can tell the difference between a system
63 * error, a test error, etc.
64 */
65#define PIDFD_PASS 0
66#define PIDFD_FAIL 1
67#define PIDFD_ERROR 2
68#define PIDFD_SKIP 3
69#define PIDFD_XFAIL 4
70
71static inline int wait_for_pid(pid_t pid)
72{
73 int status, ret;
74
75again:
76 ret = waitpid(pid, &status, 0);
77 if (ret == -1) {
78 if (errno == EINTR)
79 goto again;
80
81 ksft_print_msg(msg: "waitpid returned -1, errno=%d\n", errno);
82 return -1;
83 }
84
85 if (!WIFEXITED(status)) {
86 ksft_print_msg(
87 msg: "waitpid !WIFEXITED, WIFSIGNALED=%d, WTERMSIG=%d\n",
88 WIFSIGNALED(status), WTERMSIG(status));
89 return -1;
90 }
91
92 ret = WEXITSTATUS(status);
93 return ret;
94}
95
96static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
97{
98 return syscall(__NR_pidfd_open, pid, flags);
99}
100
101static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
102 unsigned int flags)
103{
104 return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
105}
106
107static inline int sys_pidfd_getfd(int pidfd, int fd, int flags)
108{
109 return syscall(__NR_pidfd_getfd, pidfd, fd, flags);
110}
111
112static inline int sys_memfd_create(const char *name, unsigned int flags)
113{
114 return syscall(__NR_memfd_create, name, flags);
115}
116
117#endif /* __PIDFD_H */
118

source code of linux/tools/testing/selftests/pidfd/pidfd.h