1 /* Test for vfork functions.
2 Copyright (C) 2004-2022 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 #include <errno.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <unistd.h>
23 #include <sys/types.h>
24 #include <sys/wait.h>
25
26 /* This test relies on non-POSIX functionality since the child
27 processes call write and getpid. */
28 static int
do_test(void)29 do_test (void)
30 {
31 int result = 0;
32 int fd[2];
33
34 if (pipe (fd) == -1)
35 {
36 puts ("pipe failed");
37 return 1;
38 }
39
40 /* First vfork() without previous getpid(). */
41 pid_t p1;
42 if ((p1 = vfork ()) == 0)
43 {
44 pid_t p = getpid ();
45 _exit (TEMP_FAILURE_RETRY (write (fd[1], &p, sizeof (p))) != sizeof (p));
46 }
47 else if (p1 == -1)
48 {
49 puts ("1st vfork failed");
50 result = 1;
51 }
52
53 pid_t p2 = 0;
54 if (TEMP_FAILURE_RETRY (read (fd[0], &p2, sizeof (pid_t))) != sizeof (pid_t))
55 {
56 puts ("1st read failed");
57 result = 1;
58 }
59 int r;
60 if (TEMP_FAILURE_RETRY (waitpid (p1, &r, 0)) != p1)
61 {
62 puts ("1st waitpid failed");
63 result = 1;
64 }
65 else if (r != 0)
66 {
67 puts ("write in 1st child failed");
68 result = 1;
69 }
70
71 /* Main process' ID. */
72 pid_t p0 = getpid ();
73
74 /* vfork() again, but after a getpid() in the main process. */
75 pid_t p3;
76 if ((p3 = vfork ()) == 0)
77 {
78 pid_t p = getpid ();
79 _exit (TEMP_FAILURE_RETRY (write (fd[1], &p, sizeof (p))) != sizeof (p));
80 }
81 else if (p1 == -1)
82 {
83 puts ("2nd vfork failed");
84 result = 1;
85 }
86
87 pid_t p4;
88 if (TEMP_FAILURE_RETRY (read (fd[0], &p4, sizeof (pid_t))) != sizeof (pid_t))
89 {
90 puts ("2nd read failed");
91 result = 1;
92 }
93 if (TEMP_FAILURE_RETRY (waitpid (p3, &r, 0)) != p3)
94 {
95 puts ("2nd waitpid failed");
96 result = 1;
97 }
98 else if (r != 0)
99 {
100 puts ("write in 2nd child failed");
101 result = 1;
102 }
103
104 /* And getpid in the main process again. */
105 pid_t p5 = getpid ();
106
107 /* Analysis of the results. */
108 if (p0 != p5)
109 {
110 printf ("p0(%ld) != p5(%ld)\n", (long int) p0, (long int) p5);
111 result = 1;
112 }
113
114 if (p0 == p1)
115 {
116 printf ("p0(%ld) == p1(%ld)\n", (long int) p0, (long int) p1);
117 result = 1;
118 }
119
120 if (p1 != p2)
121 {
122 printf ("p1(%ld) != p2(%ld)\n", (long int) p1, (long int) p2);
123 result = 1;
124 }
125
126 if (p0 == p3)
127 {
128 printf ("p0(%ld) == p3(%ld)\n", (long int) p0, (long int) p3);
129 result = 1;
130 }
131
132 if (p3 != p4)
133 {
134 printf ("p3(%ld) != p4(%ld)\n", (long int) p3, (long int) p4);
135 result = 1;
136 }
137
138 close (fd[0]);
139 close (fd[1]);
140
141 if (result == 0)
142 puts ("All OK");
143
144 return result;
145 }
146
147 #define TEST_FUNCTION do_test ()
148 #include "../test-skeleton.c"
149