1 /* Copyright (C) 2002-2023 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
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.
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.
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/>. */
32 size_t ps
= sysconf (_SC_PAGESIZE
);
33 char tmpfname
[] = "/tmp/tst-rwlock12.XXXXXX";
38 pthread_mutexattr_t ma
;
40 pthread_rwlockattr_t ra
;
44 fd
= mkstemp (tmpfname
);
47 printf ("cannot open temporary file: %m\n");
51 /* Make sure it is always removed. */
54 /* Create one page of data. */
55 memset (data
, '\0', ps
);
57 /* Write the data to the file. */
58 if (write (fd
, data
, ps
) != (ssize_t
) ps
)
64 mem
= mmap (NULL
, ps
, PROT_READ
| PROT_WRITE
, MAP_SHARED
, fd
, 0);
65 if (mem
== MAP_FAILED
)
67 printf ("mmap failed: %m\n");
71 r
= (pthread_rwlock_t
*) (((uintptr_t) mem
+ __alignof (pthread_rwlock_t
))
72 & ~(__alignof (pthread_rwlock_t
) - 1));
73 /* The following assumes alignment for a mutex is at least as high
74 as that for a rwlock. Which is true in our case. */
75 m
= (pthread_mutex_t
*) (r
+ 1);
77 if (pthread_rwlockattr_init (&ra
) != 0)
79 puts ("rwlockattr_init failed");
83 if (pthread_rwlockattr_setpshared (&ra
, PTHREAD_PROCESS_SHARED
) != 0)
85 puts ("rwlockattr_setpshared failed");
89 if (pthread_rwlock_init (r
, &ra
) != 0)
91 puts ("rwlock_init failed");
95 if (pthread_mutexattr_init (&ma
) != 0)
97 puts ("rwlockattr_init failed");
101 if (pthread_mutexattr_setpshared (&ma
, PTHREAD_PROCESS_SHARED
) != 0)
103 puts ("mutexattr_setpshared failed");
107 if (pthread_mutex_init (m
, &ma
) != 0)
109 puts ("mutex_init failed");
113 /* Lock the mutex. */
114 if (pthread_mutex_lock (m
) != 0)
116 puts ("mutex_lock failed");
120 puts ("going to fork now");
124 puts ("fork failed");
129 /* Lock the mutex. */
130 if (pthread_mutex_lock (m
) != 0)
132 puts ("child: mutex_lock failed");
136 /* Try to get the rwlock. */
137 if (pthread_rwlock_trywrlock (r
) == 0)
139 puts ("rwlock_trywrlock succeeded");
144 struct timespec ts
= { .tv_sec
= 0, .tv_nsec
= 500000000 };
145 int e
= pthread_rwlock_timedwrlock (r
, &ts
);
148 puts ("rwlock_timedwrlock succeeded");
153 puts ("rwlock_timedwrlock didn't return ETIMEDOUT");
157 if (pthread_rwlock_tryrdlock (r
) == 0)
159 puts ("rwlock_tryrdlock succeeded");
163 e
= pthread_rwlock_timedrdlock (r
, &ts
);
166 puts ("rwlock_timedrdlock succeeded");
171 puts ("rwlock_timedrdlock didn't return ETIMEDOUT");
177 /* Lock the rwlock for writing. */
178 if (pthread_rwlock_wrlock (r
) != 0)
180 puts ("rwlock_wrlock failed");
185 /* Allow the child to run. */
186 if (pthread_mutex_unlock (m
) != 0)
188 puts ("mutex_unlock failed");
193 /* Just wait for the child. */
194 if (TEMP_FAILURE_RETRY (waitpid (pid
, &status
, 0)) != pid
)
196 puts ("waitpid failed");
205 #define TEST_FUNCTION do_test ()
206 #include "../test-skeleton.c"