1 /* Test for vfork functions.
2 Copyright (C) 2004-2023 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 <signal.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <time.h>
25 #include <unistd.h>
26 #include <sys/time.h>
27 #include <sys/types.h>
28 #include <sys/wait.h>
29
30 int raise_fail;
31
32 static void
33 alrm (int sig)
34 {
35 if (raise (SIGUSR1) < 0)
36 raise_fail = 1;
37 }
38
39 /* This test relies on non-POSIX functionality since the child
40 processes call write, nanosleep and getpid. */
41 static int
42 do_test (void)
43 {
44 int result = 0;
45 int fd[2];
46
47 signal (SIGUSR1, SIG_IGN);
48
49 struct sigaction sa;
50 sa.sa_handler = alrm;
51 sigemptyset (&sa.sa_mask);
52 sa.sa_flags = 0;
53 if (sigaction (SIGALRM, &sa, NULL) < 0)
54 {
55 puts ("couldn't set up SIGALRM handler");
56 return 1;
57 }
58
59 if (pipe (fd) == -1)
60 {
61 puts ("pipe failed");
62 return 1;
63 }
64
65 struct itimerval it;
66 it.it_value.tv_sec = 0;
67 it.it_value.tv_usec = 200 * 1000;
68 it.it_interval = it.it_value;
69 if (setitimer (ITIMER_REAL, &it, NULL) < 0)
70 {
71 puts ("couldn't set up timer");
72 return 1;
73 }
74
75 /* First vfork() without previous getpid(). */
76 pid_t p1;
77 if ((p1 = vfork ()) == 0)
78 {
79 pid_t p = getpid ();
80
81 struct timespec ts;
82 ts.tv_sec = 1;
83 ts.tv_nsec = 0;
84 TEMP_FAILURE_RETRY (nanosleep (&ts, &ts));
85 _exit (TEMP_FAILURE_RETRY (write (fd[1], &p, sizeof (p))) != sizeof (p));
86 }
87 else if (p1 == -1)
88 {
89 puts ("1st vfork failed");
90 result = 1;
91 }
92
93 memset (&it, 0, sizeof (it));
94 setitimer (ITIMER_REAL, &it, NULL);
95
96 pid_t p2 = 0;
97 if (TEMP_FAILURE_RETRY (read (fd[0], &p2, sizeof (pid_t))) != sizeof (pid_t))
98 {
99 puts ("1st read failed");
100 result = 1;
101 }
102 int r;
103 if (TEMP_FAILURE_RETRY (waitpid (p1, &r, 0)) != p1)
104 {
105 puts ("1st waitpid failed");
106 result = 1;
107 }
108 else if (r != 0)
109 {
110 puts ("write in 1st child failed");
111 result = 1;
112 }
113
114 /* Main process' ID. */
115 pid_t p0 = getpid ();
116
117 /* vfork() again, but after a getpid() in the main process. */
118 pid_t p3;
119 if ((p3 = vfork ()) == 0)
120 {
121 pid_t p = getpid ();
122 _exit (TEMP_FAILURE_RETRY (write (fd[1], &p, sizeof (p))) != sizeof (p));
123 }
124 else if (p1 == -1)
125 {
126 puts ("2nd vfork failed");
127 result = 1;
128 }
129
130 pid_t p4;
131 if (TEMP_FAILURE_RETRY (read (fd[0], &p4, sizeof (pid_t))) != sizeof (pid_t))
132 {
133 puts ("2nd read failed");
134 result = 1;
135 }
136 if (TEMP_FAILURE_RETRY (waitpid (p3, &r, 0)) != p3)
137 {
138 puts ("2nd waitpid failed");
139 result = 1;
140 }
141 else if (r != 0)
142 {
143 puts ("write in 2nd child failed");
144 result = 1;
145 }
146
147 /* And getpid in the main process again. */
148 pid_t p5 = getpid ();
149
150 /* Analysis of the results. */
151 if (p0 != p5)
152 {
153 printf ("p0(%ld) != p5(%ld)\n", (long int) p0, (long int) p5);
154 result = 1;
155 }
156
157 if (p0 == p1)
158 {
159 printf ("p0(%ld) == p1(%ld)\n", (long int) p0, (long int) p1);
160 result = 1;
161 }
162
163 if (p1 != p2)
164 {
165 printf ("p1(%ld) != p2(%ld)\n", (long int) p1, (long int) p2);
166 result = 1;
167 }
168
169 if (p0 == p3)
170 {
171 printf ("p0(%ld) == p3(%ld)\n", (long int) p0, (long int) p3);
172 result = 1;
173 }
174
175 if (p3 != p4)
176 {
177 printf ("p3(%ld) != p4(%ld)\n", (long int) p3, (long int) p4);
178 result = 1;
179 }
180
181 close (fd[0]);
182 close (fd[1]);
183
184 if (raise_fail)
185 {
186 puts ("raise failed");
187 result = 1;
188 }
189
190 if (result == 0)
191 puts ("All OK");
192
193 return result;
194 }
195
196 #define TEST_FUNCTION do_test ()
197 #include "../test-skeleton.c"