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/* $OpenBSD: msgtest.c,v 1.6 2008/06/26 05:42:06 ray Exp $ */
/* $NetBSD: msgtest.c,v 1.6 2001/02/19 22:44:41 cgd Exp $ */
/*-
* Copyright (c) 1999 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Test the SVID-compatible Message Queue facility.
*/
#include <sys/param.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <sys/wait.h>
#include <err.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
int main(int, char *[]);
void print_msqid_ds(struct msqid_ds *, mode_t);
void sigsys_handler(int);
void sigchld_handler(int);
void cleanup(void);
void receiver(void);
#define MESSAGE_TEXT_LEN 256
struct thismsg {
long mtype;
char mtext[MESSAGE_TEXT_LEN];
};
const char *m1_str = "California is overrated.";
const char *m2_str = "The quick brown fox jumped over the lazy dog.";
#define MTYPE_1 1
#define MTYPE_1_ACK 2
#define MTYPE_2 3
#define MTYPE_2_ACK 4
int sender_msqid = -1;
pid_t child_pid;
key_t msgkey;
char keyname[] = "/tmp/msgtestXXXXXXXX";
int verbose;
int
main(int argc, char **argv)
{
struct sigaction sa;
struct msqid_ds m_ds;
struct thismsg m;
sigset_t sigmask;
int fd, ch;
if ((fd = mkstemp(keyname)) < 0)
err(1, "mkstemp");
close(fd);
while ((ch = getopt(argc, argv, "v")) != -1) {
switch (ch) {
case 'v':
verbose = 1;
break;
default:
fprintf(stderr, "Usage: msgtest [-v]\n");
exit(1);
}
}
/*
* Install a SIGSYS handler so that we can exit gracefully if
* System V Message Queue support isn't in the kernel.
*/
sa.sa_handler = sigsys_handler;
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
if (sigaction(SIGSYS, &sa, NULL) == -1)
err(1, "sigaction SIGSYS");
/*
* Install and SIGCHLD handler to deal with all possible exit
* conditions of the receiver.
*/
sa.sa_handler = sigchld_handler;
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
if (sigaction(SIGCHLD, &sa, NULL) == -1)
err(1, "sigaction SIGCHLD");
msgkey = ftok(keyname, 4160);
/*
* Initialize child_pid to ourselves to that the cleanup function
* works before we create the receiver.
*/
child_pid = getpid();
/*
* Make sure that when the sender exits, the message queue is
* removed.
*/
if (atexit(cleanup) == -1)
err(1, "atexit");
if ((sender_msqid = msgget(msgkey, IPC_CREAT | 0640)) == -1)
err(1, "msgget");
if (msgctl(sender_msqid, IPC_STAT, &m_ds) == -1)
err(1, "msgctl IPC_STAT");
if (verbose)
print_msqid_ds(&m_ds, 0640);
m_ds.msg_perm.mode = (m_ds.msg_perm.mode & ~0777) | 0600;
if (msgctl(sender_msqid, IPC_SET, &m_ds) == -1)
err(1, "msgctl IPC_SET");
memset(&m_ds, 0, sizeof(m_ds));
if (msgctl(sender_msqid, IPC_STAT, &m_ds) == -1)
err(1, "msgctl IPC_STAT");
if ((m_ds.msg_perm.mode & 0777) != 0600)
err(1, "IPC_SET of mode didn't hold");
if (verbose)
print_msqid_ds(&m_ds, 0600);
switch ((child_pid = fork())) {
case -1:
err(1, "fork");
/* NOTREACHED */
case 0:
receiver();
break;
default:
break;
}
/*
* Send the first message to the receiver and wait for the ACK.
*/
m.mtype = MTYPE_1;
strlcpy(m.mtext, m1_str, sizeof m.mtext);
if (msgsnd(sender_msqid, &m, sizeof(m), 0) == -1)
err(1, "sender: msgsnd 1");
if (msgrcv(sender_msqid, &m, sizeof(m), MTYPE_1_ACK, 0) != sizeof(m))
err(1, "sender: msgrcv 1 ack");
if (verbose)
print_msqid_ds(&m_ds, 0600);
/*
* Send the second message to the receiver and wait for the ACK.
*/
m.mtype = MTYPE_2;
strlcpy(m.mtext, m2_str, sizeof m.mtext);
if (msgsnd(sender_msqid, &m, sizeof(m), 0) == -1)
err(1, "sender: msgsnd 2");
if (msgrcv(sender_msqid, &m, sizeof(m), MTYPE_2_ACK, 0) != sizeof(m))
err(1, "sender: msgrcv 2 ack");
/*
* Suspend forever; when we get SIGCHLD, the handler will exit.
*/
sigemptyset(&sigmask);
(void) sigsuspend(&sigmask);
/*
* ...and any other signal is an unexpected error.
*/
errx(1, "sender: received unexpected signal");
}
void
sigsys_handler(signo)
int signo;
{
errx(1, "System V Message Queue support is not present in the kernel");
}
void
sigchld_handler(signo)
int signo;
{
struct msqid_ds m_ds;
int cstatus;
/*
* Reap the child; if it exited successfully, then the test passed!
*/
if (waitpid(child_pid, &cstatus, 0) != child_pid)
err(1, "waitpid");
if (WIFEXITED(cstatus) == 0)
errx(1, "receiver exited abnormally");
if (WEXITSTATUS(cstatus) != 0)
errx(1, "receiver exited with status %d",
WEXITSTATUS(cstatus));
/*
* If we get here, the child has exited normally, and thus
* we should exit normally too. First, tho, we print out
* the final stats for the message queue.
*/
if (msgctl(sender_msqid, IPC_STAT, &m_ds) == -1)
err(1, "msgctl IPC_STAT");
if (verbose)
print_msqid_ds(&m_ds, 0600);
exit(0);
}
void
cleanup()
{
/*
* If we're the sender, and it exists, remove the message queue.
*/
if (child_pid != 0 && sender_msqid != -1) {
if (msgctl(sender_msqid, IPC_RMID, NULL) == -1)
warn("msgctl IPC_RMID");
}
remove(keyname);
}
void
print_msqid_ds(mp, mode)
struct msqid_ds *mp;
mode_t mode;
{
uid_t uid = geteuid();
gid_t gid = getegid();
printf("PERM: uid %u, gid %u, cuid %u, cgid %u, mode 0%o\n",
mp->msg_perm.uid, mp->msg_perm.gid,
mp->msg_perm.cuid, mp->msg_perm.cgid,
mp->msg_perm.mode & 0777);
printf("qnum %lu, qbytes %lu, lspid %d, lrpid %d\n",
mp->msg_qnum, (u_long)mp->msg_qbytes, mp->msg_lspid,
mp->msg_lrpid);
printf("stime: %s", ctime(&mp->msg_stime));
printf("rtime: %s", ctime(&mp->msg_rtime));
printf("ctime: %s", ctime(&mp->msg_ctime));
/*
* Sanity check a few things.
*/
if (mp->msg_perm.uid != uid || mp->msg_perm.cuid != uid)
errx(1, "uid mismatch");
if (mp->msg_perm.gid != gid || mp->msg_perm.cgid != gid)
errx(1, "gid mismatch");
if ((mp->msg_perm.mode & 0777) != mode)
errx(1, "mode mismatch");
}
void
receiver()
{
struct thismsg m;
int msqid;
if ((msqid = msgget(msgkey, 0)) == -1)
err(1, "receiver: msgget");
/*
* Receive the first message, print it, and send an ACK.
*/
if (msgrcv(msqid, &m, sizeof(m), MTYPE_1, 0) != sizeof(m))
err(1, "receiver: msgrcv 1");
if (verbose)
printf("%s\n", m.mtext);
if (strcmp(m.mtext, m1_str) != 0)
err(1, "receiver: message 1 data isn't correct");
m.mtype = MTYPE_1_ACK;
if (msgsnd(msqid, &m, sizeof(m), 0) == -1)
err(1, "receiver: msgsnd ack 1");
/*
* Receive the second message, print it, and send an ACK.
*/
if (msgrcv(msqid, &m, sizeof(m), MTYPE_2, 0) != sizeof(m))
err(1, "receiver: msgrcv 2");
if (verbose)
printf("%s\n", m.mtext);
if (strcmp(m.mtext, m2_str) != 0)
err(1, "receiver: message 2 data isn't correct");
m.mtype = MTYPE_2_ACK;
if (msgsnd(msqid, &m, sizeof(m), 0) == -1)
err(1, "receiver: msgsnd ack 2");
exit(0);
}
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