1/*	$NetBSD: getport.c,v 1.1 2004/10/16 02:03:54 christos Exp $	*/
2
3/*-
4 * Copyright (c) 2004 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Christos Zoulas.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__RCSID("$NetBSD: getport.c,v 1.1 2004/10/16 02:03:54 christos Exp $");
34
35#include <stdlib.h>
36#include <err.h>
37#include <netdb.h>
38#include <limits.h>
39#include <errno.h>
40#include <netinet/in.h>
41
42#include "getport.h"
43
44struct servent *
45getport(const char *service, const char *protocol)
46{
47	long port;
48	char *ep;
49	struct servent *sp = getservbyname(service, protocol);
50	if (sp != NULL)
51		return sp;
52
53	if ((sp = calloc(1, sizeof(*sp))) == NULL)
54		err(1, "malloc");
55	sp->s_name = __UNCONST(service);
56	sp->s_proto = __UNCONST(protocol);
57	port = strtol(service, &ep, 0);
58	if ((service[0] != '\0' && *ep != '\0') ||
59	    (errno == ERANGE &&
60	    (port == LONG_MAX || port == LONG_MIN)) ||
61	    (port <= 0 || port >= IPPORT_ANONMAX))
62		errx(1,"port must be between 1 and %d",
63		    IPPORT_ANONMAX);
64	sp->s_port = htons((uint16_t)port);
65	return sp;
66}
67