StdLib/BsdSocketLib/gethostbyht.c

/*-
 * Copyright (c) 1985, 1988, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Portions copyright (c) 1999, 2000
 * Intel Corporation.
 * 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, Intel Corporation, and its contributors.
 * 
 * 4. Neither the name of University, Intel Corporation, or their respective
 *    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, INTEL CORPORATION 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,
 * INTEL CORPORATION 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.
 *
 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies, and that
 * the name of Digital Equipment Corporation not be used in advertising or
 * publicity pertaining to distribution of the document or software without
 * specific, written prior permission.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 * -
 * --Copyright--
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)gethostnamadr.c	8.1 (Berkeley) 6/4/93";
static char rcsid[] = "$Id: gethostbyht.c,v 1.1.1.1 2003/11/19 01:51:27 kyu3 Exp $";
#endif /* LIBC_SCCS and not lint */

#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <arpa/nameser.h>	/* XXX */
#include <resolv.h>		/* XXX */
#include "Socklib_internals.h"

#define	MAXALIASES	35

static struct hostent host;
static char *host_aliases[MAXALIASES];
static char hostbuf[BUFSIZ+1];
static FILE *hostf = NULL;
static u_char host_addr[16];	/* IPv4 or IPv6 */
static char *h_addr_ptrs[2];
static int stayopen = 0;

void
_sethosthtent(int f)
{
	if (!hostf)
		hostf = fopen(_PATH_HOSTS, "r" );
	else
		rewind(hostf);
	stayopen = f;
}

void
_endhosthtent()
{
	if (hostf && !stayopen) {
		(void) fclose(hostf);
		hostf = NULL;
	}
}

struct hostent *
gethostent()
{
	char *p;
	register char *cp, **q;
	int af, len;

	if (!hostf && ( NULL == (hostf = fopen(_PATH_HOSTS, "r" )))) {
		h_errno = NETDB_INTERNAL;
		return (NULL);
	}
 again:
	if ( NULL == (p = fgets(hostbuf, sizeof hostbuf, hostf))) {
		h_errno = HOST_NOT_FOUND;
		return (NULL);
	}
	if (*p == '#')
		goto again;
	if ( NULL == (cp = strpbrk(p, "#\n")))
		goto again;
	*cp = '\0';
	if ( NULL == (cp = strpbrk(p, " \t")))
		goto again;
	*cp++ = '\0';
	if (inet_pton(AF_INET6, p, host_addr) > 0) {
		af = AF_INET6;
		len = IN6ADDRSZ;
	} else if (inet_pton(AF_INET, p, host_addr) > 0) {
		if (_res.options & RES_USE_INET6) {
			_map_v4v6_address((char*)host_addr, (char*)host_addr);
			af = AF_INET6;
			len = IN6ADDRSZ;
		} else {
			af = AF_INET;
			len = INADDRSZ;
		}
	} else {
		goto again;
	}
	h_addr_ptrs[0] = (char *)host_addr;
	h_addr_ptrs[1] = NULL;
	host.h_addr_list = h_addr_ptrs;
	host.h_length = len;
	host.h_addrtype = af;
	while (*cp == ' ' || *cp == '\t')
		cp++;
	host.h_name = cp;
	q = host.h_aliases = host_aliases;
	if ((cp = strpbrk(cp, " \t\r")) != NULL)
		*cp++ = '\0';
	while (cp && *cp) {
		if (*cp == ' ' || *cp == '\t') {
			cp++;
			continue;
		}
		if (q < &host_aliases[MAXALIASES - 1])
			*q++ = cp;
		if ((cp = strpbrk(cp, " \t\r")) != NULL)
			*cp++ = '\0';
	}
	*q = NULL;
	h_errno = NETDB_SUCCESS;
	return (&host);
}

struct hostent *
_gethostbyhtname(const char *name, int af)
{
	register struct hostent *p;
	register char **cp;
	
	sethostent(0);
	while ((p = gethostent()) != NULL) {
		if (p->h_addrtype != af)
			continue;
		if (strcasecmp(p->h_name, name) == 0)
			break;
		for (cp = p->h_aliases; *cp != 0; cp++)
			if (strcasecmp(*cp, name) == 0)
				goto found;
	}
found:
	endhostent();
	return (p);
}

struct hostent *
_gethostbyhtaddr(const char *addr, int len, int af)
{
	register struct hostent *p;

	sethostent(0);
	while ((p = gethostent()) != NULL)
		if (p->h_addrtype == af && !bcmp(p->h_addr, addr, len))
			break;
	endhostent();
	return (p);
}