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/* $OpenBSD: accept.c,v 1.4 2004/02/28 03:29:15 deraadt Exp $ */
/*
* Written by Artur Grabowski <art@openbsd.org>, 2002 Public Domain.
*/
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <sys/un.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <err.h>
#include <signal.h>
#include <string.h>
#define SOCK_NAME "test-sock"
int child(void);
int
main(int argc, char *argv[])
{
int listensock, sock;
struct sockaddr_un sun, csun;
int csunlen;
int fd, lastfd;
int status;
int ischild = 0;
/*
* Create the listen socket.
*/
if ((listensock = socket(PF_LOCAL, SOCK_STREAM, 0)) == -1)
err(1, "socket");
unlink(SOCK_NAME);
memset(&sun, 0, sizeof(sun));
sun.sun_family = AF_LOCAL;
strlcpy(sun.sun_path, SOCK_NAME, sizeof sun.sun_path);
sun.sun_len = SUN_LEN(&sun);
if (bind(listensock, (struct sockaddr *)&sun, sizeof(sun)) == -1)
err(1, "bind");
if (listen(listensock, 1) == -1)
err(1, "listen");
switch (fork()) {
case -1:
err(1, "fork");
case 0:
return child();
}
while ((fd = open("/dev/null", O_RDONLY)) >= 0)
lastfd = fd;
switch (fork()) {
case -1:
err(1, "fork");
case 0:
ischild = 1;
close(lastfd); /* Close one fd so that accept can succeed */
sleep(2); /* sleep a bit so that we're the second to accept */
}
sock = accept(listensock, (struct sockaddr *)&csun, &csunlen);
if (!ischild && sock >= 0)
errx(1, "accept succeeded in parent");
if (ischild && sock < 0)
err(1, "accept failed in child");
while (!ischild && wait4(-1, &status, 0, NULL) > 0)
;
return (0);
}
int
child()
{
int i, fd, sock;
struct sockaddr_un sun;
/*
* Create socket and connect to the receiver.
*/
if ((sock = socket(PF_LOCAL, SOCK_STREAM, 0)) == -1)
errx(1, "child socket");
(void) memset(&sun, 0, sizeof(sun));
sun.sun_family = AF_LOCAL;
(void) strlcpy(sun.sun_path, SOCK_NAME, sizeof sun.sun_path);
sun.sun_len = SUN_LEN(&sun);
if (connect(sock, (struct sockaddr *)&sun, sizeof(sun)) == -1)
err(1, "child connect");
return (0);
}
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