1/* Copyright (C) 2002-2024 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <errno.h>
19#include <pthread.h>
20#include <stdint.h>
21#include <stdio.h>
22#include <stdlib.h>
23#include <string.h>
24#include <unistd.h>
25#include <sys/mman.h>
26#include <sys/wait.h>
27
28
29static int
30do_test (void)
31{
32 size_t ps = sysconf (_SC_PAGESIZE);
33 char tmpfname[] = "/tmp/tst-mutex4.XXXXXX";
34 char data[ps];
35 void *mem;
36 int fd;
37 pthread_mutex_t *m;
38 pthread_mutexattr_t a;
39 pid_t pid;
40 char *p;
41 int err;
42 int s;
43 pthread_barrier_t *b;
44 pthread_barrierattr_t ba;
45
46 fd = mkstemp (template: tmpfname);
47 if (fd == -1)
48 {
49 printf (format: "cannot open temporary file: %m\n");
50 return 1;
51 }
52
53 /* Make sure it is always removed. */
54 unlink (name: tmpfname);
55
56 /* Create one page of data. */
57 memset (data, '\0', ps);
58
59 /* Write the data to the file. */
60 if (write (fd, data, ps) != (ssize_t) ps)
61 {
62 puts (s: "short write");
63 return 1;
64 }
65
66 mem = mmap (NULL, len: ps, PROT_READ | PROT_WRITE, MAP_SHARED, fd: fd, offset: 0);
67 if (mem == MAP_FAILED)
68 {
69 printf (format: "mmap failed: %m\n");
70 return 1;
71 }
72
73 m = (pthread_mutex_t *) (((uintptr_t) mem + __alignof (pthread_mutex_t) - 1)
74 & ~(__alignof (pthread_mutex_t) - 1));
75 b = (pthread_barrier_t *) (((uintptr_t) (m + 1)
76 + __alignof (pthread_barrier_t) - 1)
77 & ~(__alignof (pthread_barrier_t) - 1));
78 p = (char *) (b + 1);
79
80 if (pthread_mutexattr_init (attr: &a) != 0)
81 {
82 puts (s: "mutexattr_init failed");
83 return 1;
84 }
85
86 if (pthread_mutexattr_getpshared (attr: &a, pshared: &s) != 0)
87 {
88 puts (s: "1st mutexattr_getpshared failed");
89 return 1;
90 }
91
92 if (s != PTHREAD_PROCESS_PRIVATE)
93 {
94 puts (s: "default pshared value wrong");
95 return 1;
96 }
97
98 if (pthread_mutexattr_setpshared (attr: &a, PTHREAD_PROCESS_SHARED) != 0)
99 {
100 puts (s: "mutexattr_setpshared failed");
101 return 1;
102 }
103
104 if (pthread_mutexattr_getpshared (attr: &a, pshared: &s) != 0)
105 {
106 puts (s: "2nd mutexattr_getpshared failed");
107 return 1;
108 }
109
110 if (s != PTHREAD_PROCESS_SHARED)
111 {
112 puts (s: "pshared value after setpshared call wrong");
113 return 1;
114 }
115
116#ifdef ENABLE_PI
117 if (pthread_mutexattr_setprotocol (attr: &a, protocol: PTHREAD_PRIO_INHERIT) != 0)
118 {
119 puts (s: "pthread_mutexattr_setprotocol failed");
120 return 1;
121 }
122#endif
123
124 if ((err = pthread_mutex_init (mutex: m, mutexattr: &a)) != 0)
125 {
126#ifdef ENABLE_PI
127 if (err == ENOTSUP)
128 {
129 puts (s: "PI mutexes unsupported");
130 return 0;
131 }
132#endif
133 puts (s: "mutex_init failed");
134 return 1;
135 }
136
137 if (pthread_mutex_lock (mutex: m) != 0)
138 {
139 puts (s: "mutex_lock failed");
140 return 1;
141 }
142
143 if (pthread_mutexattr_destroy (attr: &a) != 0)
144 {
145 puts (s: "mutexattr_destroy failed");
146 return 1;
147 }
148
149 if (pthread_barrierattr_init (attr: &ba) != 0)
150 {
151 puts (s: "barrierattr_init failed");
152 return 1;
153 }
154
155 if (pthread_barrierattr_setpshared (attr: &ba, PTHREAD_PROCESS_SHARED) != 0)
156 {
157 puts (s: "barrierattr_setpshared failed");
158 return 1;
159 }
160
161 if (pthread_barrier_init (barrier: b, attr: &ba, count: 2) != 0)
162 {
163 puts (s: "barrier_init failed");
164 return 1;
165 }
166
167 if (pthread_barrierattr_destroy (attr: &ba) != 0)
168 {
169 puts (s: "barrierattr_destroy failed");
170 return 1;
171 }
172
173 err = pthread_mutex_trylock (mutex: m);
174 if (err == 0)
175 {
176 puts (s: "mutex_trylock succeeded");
177 return 1;
178 }
179 else if (err != EBUSY)
180 {
181 puts (s: "mutex_trylock didn't return EBUSY");
182 return 1;
183 }
184
185 *p = 0;
186
187 if (pthread_mutex_unlock (mutex: m) != 0)
188 {
189 puts (s: "parent: 1st mutex_unlock failed");
190 return 1;
191 }
192
193 puts (s: "going to fork now");
194 pid = fork ();
195 if (pid == -1)
196 {
197 puts (s: "fork failed");
198 return 1;
199 }
200 else if (pid == 0)
201 {
202 if (pthread_mutex_lock (mutex: m) != 0)
203 {
204 puts (s: "child: mutex_lock failed");
205 return 1;
206 }
207
208 int e = pthread_barrier_wait (barrier: b);
209 if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
210 {
211 puts (s: "child: barrier_wait failed");
212 return 1;
213 }
214
215 if ((*p)++ != 0)
216 {
217 puts (s: "child: *p != 0");
218 return 1;
219 }
220
221 if (pthread_mutex_unlock (mutex: m) != 0)
222 {
223 puts (s: "child: mutex_unlock failed");
224 return 1;
225 }
226
227 puts (s: "child done");
228 }
229 else
230 {
231 int e = pthread_barrier_wait (barrier: b);
232 if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
233 {
234 puts (s: "parent: barrier_wait failed");
235 return 1;
236 }
237
238 if (pthread_mutex_lock (mutex: m) != 0)
239 {
240 puts (s: "parent: 2nd mutex_lock failed");
241 return 1;
242 }
243
244 if (*p != 1)
245 {
246 puts (s: "*p != 1");
247 return 1;
248 }
249
250 if (pthread_mutex_unlock (mutex: m) != 0)
251 {
252 puts (s: "parent: 2nd mutex_unlock failed");
253 return 1;
254 }
255
256 if (pthread_mutex_destroy (mutex: m) != 0)
257 {
258 puts (s: "mutex_destroy failed");
259 return 1;
260 }
261
262 if (pthread_barrier_destroy (barrier: b) != 0)
263 {
264 puts (s: "barrier_destroy failed");
265 return 1;
266 }
267
268 puts (s: "parent done");
269 }
270
271 return 0;
272}
273
274#define TEST_FUNCTION do_test ()
275#include "../test-skeleton.c"
276

source code of glibc/sysdeps/pthread/tst-mutex4.c