get_myaddress.c

操作系统SunOS 4.1.3版本的源码

#if !defined(lint) && defined(SCCSIDS)
static char sccsid[] = "@(#)get_myaddress.c 1.1 92/07/30 Copyr 1990 Sun Micro";
#endif

/*
 * get_myaddress.c
 *
 * Get client's IP address via ioctl.  This avoids using the NIS.
 * Copyright (C) 1990, Sun Microsystems, Inc.
 */

#include <rpc/types.h>
#include <rpc/pmap_prot.h>
#include <sys/socket.h>
#include <stdio.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/syslog.h>

/*
 * don't use gethostbyname, which would invoke NIS
 */
get_myaddress(addr)
	struct sockaddr_in *addr;
{
	int s;
	char buf[BUFSIZ*8];
	struct ifconf ifc;
	struct ifreq ifreq, *ifr;
	int len;

	if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
	    (void) syslog(LOG_ERR, "get_myaddress: socket: %m");
	    exit(1);
	}
	ifc.ifc_len = sizeof (buf);
	ifc.ifc_buf = buf;
	if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) {
		(void) syslog(LOG_ERR,
		    "get_myaddress: ioctl (get interface configuration): %m");
		exit(1);
	}
	ifr = ifc.ifc_req;
	for (len = ifc.ifc_len; len; len -= sizeof ifreq) {
		ifreq = *ifr;
		if (ioctl(s, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
			(void) syslog(LOG_ERR, "get_myaddress: ioctl: %m");
			exit(1);
		}
		if ((ifreq.ifr_flags & IFF_UP) &&
		    ifr->ifr_addr.sa_family == AF_INET) {
			*addr = *((struct sockaddr_in *)&ifr->ifr_addr);
			addr->sin_port = htons(PMAPPORT);
			break;
		}
		ifr++;
	}
	(void) close(s);
}