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/* $FreeBSD$ */
#include <sys/types.h>
#include <sys/select.h>
#include <sys/wait.h>
#include <err.h>
#include <fcntl.h>
#include <mqueue.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#define MQNAME "/mytstqueue3"
#define LOOPS 1000
#define PRIO 10
static void
sighandler(int sig __unused)
{
write(1, "timeout\n", 8);
_exit(1);
}
int
main(void)
{
fd_set set;
struct mq_attr attr;
int status;
mqd_t mq;
pid_t pid;
mq_unlink(MQNAME);
attr.mq_maxmsg = 5;
attr.mq_msgsize = 128;
mq = mq_open(MQNAME, O_CREAT | O_RDWR | O_EXCL, 0666, &attr);
if (mq == (mqd_t)-1)
err(1, "mq_open()");
status = mq_getattr(mq, &attr);
if (status)
err(1, "mq_getattr()");
pid = fork();
if (pid == 0) { /* child */
char *buf;
int j, i;
unsigned int prio;
mq_close(mq);
signal(SIGALRM, sighandler);
mq = mq_open(MQNAME, O_RDWR);
if (mq == (mqd_t)-1)
err(1, "child process: mq_open");
buf = malloc(attr.mq_msgsize);
for (j = 0; j < LOOPS; ++j) {
FD_ZERO(&set);
FD_SET(__mq_oshandle(mq), &set);
alarm(3);
status = select(__mq_oshandle(mq)+1, &set, NULL, NULL, NULL);
if (status != 1)
err(1, "child process: select()");
status = mq_receive(mq, buf, attr.mq_msgsize, &prio);
if (status == -1)
err(2, "child process: mq_receive");
for (i = 0; i < attr.mq_msgsize; ++i)
if (buf[i] != i)
err(3, "message data corrupted");
if (prio != PRIO)
err(4, "priority is incorrect: %d", prio);
}
alarm(0);
free(buf);
mq_close(mq);
return (0);
} else if (pid == -1) {
err(1, "fork()");
} else {
char *buf;
int i, j;
signal(SIGALRM, sighandler);
buf = malloc(attr.mq_msgsize);
for (j = 0; j < LOOPS; ++j) {
for (i = 0; i < attr.mq_msgsize; ++i) {
buf[i] = i;
}
alarm(3);
FD_ZERO(&set);
FD_SET(__mq_oshandle(mq), &set);
status = select(__mq_oshandle(mq)+1, NULL, &set, NULL, NULL);
if (status != 1)
err(1, "select()");
status = mq_send(mq, buf, attr.mq_msgsize, PRIO);
if (status) {
kill(pid, SIGKILL);
err(2, "mq_send()");
}
}
alarm(3);
wait(&status);
alarm(0);
}
status = mq_close(mq);
if (status)
err(1, "mq_close");
mq_unlink(MQNAME);
return (0);
}
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