freebsd-src/lib/libc/net/gethostbyht.c

/*-
 * Copyright (c) 1985, 1988, 1993
 *	The 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.
 * -
 * 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 1.2 1995/05/30 05:40:44 rgrimes 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>

#define	MAXALIASES	35

static struct hostent host;
static char *host_aliases[MAXALIASES];
static char hostbuf[BUFSIZ+1];
static FILE *hostf = NULL;
static struct in_addr host_addr;
static char *h_addr_ptrs[2];
static int stayopen = 0;

void
_sethosthtent(f)
	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;

	if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) {
		h_errno = NETDB_INTERNAL;
		return (NULL);
	}
again:
	if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) {
		h_errno = HOST_NOT_FOUND;
		return (NULL);
	}
	if (*p == '#')
		goto again;
	if (!(cp = strpbrk(p, "#\n")))
		goto again;
	*cp = '\0';
	if (!(cp = strpbrk(p, " \t")))
		goto again;
	*cp++ = '\0';
	/* THIS STUFF IS INTERNET SPECIFIC */
	if (!inet_aton(p, &host_addr))
		goto again;
	h_addr_ptrs[0] = (char *)&host_addr;
	h_addr_ptrs[1] = NULL;
#if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
	host.h_addr_list = h_addr_ptrs;
#else
	host.h_addr = h_addr_ptrs[0];
#endif
	host.h_length = sizeof(u_int32_t);
	host.h_addrtype = AF_INET;
	while (*cp == ' ' || *cp == '\t')
		cp++;
	host.h_name = cp;
	q = host.h_aliases = host_aliases;
	if (cp = strpbrk(cp, " \t"))
		*cp++ = '\0';
	while (cp && *cp) {
		if (*cp == ' ' || *cp == '\t') {
			cp++;
			continue;
		}
		if (q < &host_aliases[MAXALIASES - 1])
			*q++ = cp;
		if (cp = strpbrk(cp, " \t"))
			*cp++ = '\0';
	}
	*q = NULL;
	h_errno = NETDB_SUCCESS;
	return (&host);
}

struct hostent *
_gethostbyhtname(name)
	char *name;
{
	register struct hostent *p;
	register char **cp;
	
	sethostent(0);
	while (p = gethostent()) {
		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(addr, len, type)
	const char *addr;
	int len, type;
{
	register struct hostent *p;

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