2 * Copyright (c) 1999 The NetBSD Foundation, Inc.
5 * This code is derived from software contributed to The NetBSD Foundation
6 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
7 * NASA Ames Research Center.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
18 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
19 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
22 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
30 * Obtained from: $NetBSD: semtest.c,v 1.4 2002/07/20 08:36:25 grant Exp $
35 * Test the SVID-compatible Semaphore facility.
38 #include <sys/types.h>
52 int main (int, char *[]);
53 void print_semid_ds (struct semid_ds *, mode_t);
54 void sigsys_handler (int);
55 void sigchld_handler(int);
60 int sender_semid = -1;
63 int signal_was_sigchld;
68 * This is the original semun union used by the sysvsem utility.
69 * It is deliberately kept here under #if 0'ed condition for future
70 * reference. PLEASE DO NOT REMOVE. The {SET,GET}ALL in FreeBSD
71 * are signed values, so the default version in sys/sem.h suffices.
75 int val; /* value for SETVAL */
76 struct semid_ds *buf; /* buffer for IPC_{STAT,SET} */
77 u_short *array; /* array for GETALL & SETALL */
82 main(int argc, char *argv[])
94 * Install a SIGSYS handler so that we can exit gracefully if
95 * System V Semaphore support isn't in the kernel.
97 sa.sa_handler = sigsys_handler;
98 sigemptyset(&sa.sa_mask);
100 if (sigaction(SIGSYS, &sa, NULL) == -1)
101 err(1, "sigaction SIGSYS");
104 * Install and SIGCHLD handler to deal with all possible exit
105 * conditions of the receiver.
107 sa.sa_handler = sigchld_handler;
108 sigemptyset(&sa.sa_mask);
110 if (sigaction(SIGCHLD, &sa, NULL) == -1)
111 err(1, "sigaction SIGCHLD");
113 semkey = ftok(argv[1], 4160);
116 * Initialize child_pid to ourselves to that the cleanup function
117 * works before we create the receiver.
119 child_pid = getpid();
122 * Make sure that when the sender exits, the message queue is
125 if (atexit(cleanup) == -1)
128 if ((sender_semid = semget(semkey, 1, IPC_CREAT | 0640)) == -1)
133 if (semctl(sender_semid, 0, IPC_STAT, sun) == -1)
134 err(1, "semctl IPC_STAT");
136 print_semid_ds(&s_ds, 0640);
138 s_ds.sem_perm.mode = (s_ds.sem_perm.mode & ~0777) | 0600;
141 if (semctl(sender_semid, 0, IPC_SET, sun) == -1)
142 err(1, "semctl IPC_SET");
144 memset(&s_ds, 0, sizeof(s_ds));
147 if (semctl(sender_semid, 0, IPC_STAT, sun) == -1)
148 err(1, "semctl IPC_STAT");
150 if ((s_ds.sem_perm.mode & 0777) != 0600)
151 err(1, "IPC_SET of mode didn't hold");
153 print_semid_ds(&s_ds, 0600);
156 if (semget(semkey, 1, IPC_CREAT | IPC_EXCL | 0600) != -1 ||
158 err(1, "semget IPC_EXCL 1 did not fail with [EEXIST]");
160 if (semget(semkey, 2, IPC_CREAT | IPC_EXCL | 0600) != -1 ||
162 err(1, "semget IPC_EXCL 2 did not fail with [EEXIST]");
164 for (child_count = 0; child_count < 5; child_count++) {
165 switch ((child_pid = fork())) {
180 * Wait for all of the waiters to be attempting to acquire the
184 i = semctl(sender_semid, 0, GETNCNT);
186 err(1, "semctl GETNCNT");
192 * Now set the thundering herd in motion by initializing the
193 * semaphore to the value 1.
196 if (semctl(sender_semid, 0, SETVAL, sun) == -1)
197 err(1, "sender: semctl SETVAL to 1");
200 * Suspend forever; when we get SIGCHLD, the handler will exit.
202 sigemptyset(&sigmask);
204 (void) sigsuspend(&sigmask);
205 if (signal_was_sigchld)
206 signal_was_sigchld = 0;
212 * ...and any other signal is an unexpected error.
214 errx(1, "sender: received unexpected signal");
218 sigsys_handler(int signo)
221 errx(1, "System V Semaphore support is not present in the kernel");
225 sigchld_handler(int signo)
228 struct semid_ds s_ds;
232 * Reap the child; if it exited successfully, then we're on the
235 if (wait(&cstatus) == -1)
238 if (WIFEXITED(cstatus) == 0)
239 errx(1, "receiver exited abnormally");
241 if (WEXITSTATUS(cstatus) != 0)
242 errx(1, "receiver exited with status %d",
243 WEXITSTATUS(cstatus));
246 * If we get here, the child has exited normally, and we should
247 * decrement the child count. If the child_count reaches 0, we
252 if (semctl(sender_semid, 0, IPC_STAT, sun) == -1)
253 err(1, "semctl IPC_STAT");
255 print_semid_ds(&s_ds, 0600);
257 if (--child_count != 0) {
258 signal_was_sigchld = 1;
270 * If we're the sender, and it exists, remove the message queue.
272 if (child_pid != 0 && sender_semid != -1) {
273 if (semctl(sender_semid, 0, IPC_RMID) == -1)
274 warn("semctl IPC_RMID");
279 print_semid_ds(struct semid_ds *sp, mode_t mode)
281 uid_t uid = geteuid();
282 gid_t gid = getegid();
284 printf("PERM: uid %d, gid %d, cuid %d, cgid %d, mode 0%o\n",
285 sp->sem_perm.uid, sp->sem_perm.gid,
286 sp->sem_perm.cuid, sp->sem_perm.cgid,
287 sp->sem_perm.mode & 0777);
289 printf("nsems %u\n", sp->sem_nsems);
291 printf("otime: %s", ctime(&sp->sem_otime));
292 printf("ctime: %s", ctime(&sp->sem_ctime));
295 * Sanity check a few things.
298 if (sp->sem_perm.uid != uid || sp->sem_perm.cuid != uid)
299 errx(1, "uid mismatch");
301 if (sp->sem_perm.gid != gid || sp->sem_perm.cgid != gid)
302 errx(1, "gid mismatch");
304 if ((sp->sem_perm.mode & 0777) != mode)
305 errx(1, "mode mismatch %o != %o",
306 (sp->sem_perm.mode & 0777), mode);
313 fprintf(stderr, "usage: %s keypath\n", getprogname());
323 if ((semid = semget(semkey, 1, 0)) == -1)
324 err(1, "waiter: semget");
327 * Attempt to acquire the semaphore.
331 s.sem_flg = SEM_UNDO;
333 if (semop(semid, &s, 1) == -1)
334 err(1, "waiter: semop -1");
336 printf("WOO! GOT THE SEMAPHORE!\n");
340 * Release the semaphore and exit.
344 s.sem_flg = SEM_UNDO;
346 if (semop(semid, &s, 1) == -1)
347 err(1, "waiter: semop +1");