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/*
* Copyright (c) 1983 Regents of the University of California.
* All rights reserved.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*/
/*
* From: @(#)get_addrs.c 5.7 (Berkeley) 3/1/91
*/
char ga_rcsid[] =
"$Id: get_addrs.c,v 1.7 1997/05/19 09:13:20 dholland Exp $";
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include "talk.h"
#include "talk_ctl.h"
void
get_addrs(char *my_machine_name, char *his_machine_name)
{
struct hostent *hp;
struct servent *sp;
msg.pid = htonl(getpid());
/* look up the address of the local host */
hp = gethostbyname(my_machine_name);
if (hp == NULL) {
fprintf(stderr, "talk: %s: ", my_machine_name);
herror((char *)NULL);
exit(-1);
}
if (hp->h_length > (int)sizeof(my_machine_addr)) {
hp->h_length = sizeof(my_machine_addr);
}
memcpy(&my_machine_addr, hp->h_addr, hp->h_length);
/*
* If the callee is on-machine, just copy the
* network address, otherwise do a lookup...
*/
if (strcmp(his_machine_name, my_machine_name)) {
hp = gethostbyname(his_machine_name);
if (hp == NULL) {
fprintf(stderr, "talk: %s: ", his_machine_name);
herror((char *)NULL);
exit(-1);
}
if (hp->h_length > (int)sizeof(his_machine_addr)) {
hp->h_length = sizeof(his_machine_addr);
}
memcpy(&his_machine_addr, hp->h_addr, hp->h_length);
} else
his_machine_addr = my_machine_addr;
/* find the server's port */
sp = getservbyname("ntalk", "udp");
if (sp == 0) {
fprintf(stderr, "talk: %s/%s: service is not registered.\n",
"ntalk", "udp");
exit(-1);
}
daemon_port = sp->s_port;
#ifdef BAD_LINUX_HACK
/* now some hacking to get my own address correctly routed */
{
FILE *fp;
long dest, mask;
char line[512];
struct ifreq ifr;
int s;
/* locate the proper device it has to go to */
fp = fopen("/proc/net/route","r");
fgets(line,sizeof(line),fp);
while (fscanf(fp,"%s %lx %*lx %*d %*d %*d %*d %lx %*d %*d\n",ifr.ifr_name,&dest,&mask)==3) {
if ((his_machine_addr.s_addr & mask) == dest) {
/* ok, now find out its addr, and use that as
OUR address */
s = socket(AF_INET,SOCK_DGRAM,0);
ioctl(s,SIOCGIFADDR,&ifr);
close(s);
my_machine_addr = ((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr;
break;
}
}
fclose(fp);
}
#endif
}
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