ihost/libukcprog/ip.c

/* ip.c - map hostnames */

/*  Copyright 1992  Mark Russell, University of Kent at Canterbury.
 *
 *  You can do what you like with this source code as long as
 *  you don't try to make money out of it and you include an
 *  unaltered copy of this message (including the copyright).
 */

char ukcprog_ip_sccsid[] = "$Id: ip.c,v 1.1 2002/03/08 14:37:29 tdb Exp $ UKC";

#undef _POSIX_SOURCE

#ifndef MSDOS
#include <sys/types.h>
#else
#include <sys/tk_types.h>
#endif
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>

#include <stdlib.h>
#include <string.h>
#include <stdio.h>

#include "ukcprog.h"

/*  Map a hostname to an IP address.  The address is returned in network
 *  byte order.  Return 0 for success, -1 and an error message on failure.
 *
 *  If the hostname looks like an IP quad we convert that to an IP address.
 */
int
get_host_addr(hostname, p_addr)
const char *hostname;
struct in_addr *p_addr;
{
        struct hostent *h;
        int b3, b2, b1, b0;
        char c;

        if (sscanf(hostname, "%d.%d.%d.%d%c", &b3, &b2, &b1, &b0, &c) == 4) {
                 unsigned long val;

                 val = (b3 << 24) | (b2 << 16) | (b1 << 8) | b0;
                 p_addr->s_addr = htonl(val);
                 return 0;
        }

        if ((h = gethostbyname(hostname)) == NULL) {
                errf("Can't find address of %s", hostname);
                return -1;
        }

        if (h->h_addrtype != AF_INET) {
                errf("%s has non-IP address (addrtype=%d)",
                                                hostname, h->h_addrtype);
                return -1;
        }

        memcpy((char *)p_addr, (char *)h->h_addr_list[0], sizeof(*p_addr));
        return 0;
}

/*  Map a service name to a port number in network byte order.
 *  If the service name looks like a number we return that.
 */
int
get_service_port(servname, p_port)
const char *servname;
int *p_port;
{
        struct servent *sp;
        char *endstr;
        unsigned short hport;

        hport = strtol(servname, &endstr, 0);
        if (endstr != servname && *endstr == '\0') {
                *p_port = htons(hport);
                return 0;
        }

        if ((sp = getservbyname(servname, "tcp")) == NULL) {
                errf("Unknown service `%s'", servname);
                return -1;
        }

        *p_port = sp->s_port;

        return 0;
}
Revision:	1.2
Committed:	Sat Mar 29 18:05:09 2003 UTC (21 years, 8 months ago) by tdb
Content type:	text/plain
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.1:	+1 -1 lines
State:	*FILE REMOVED*
Log Message:	ihost now makes use of an external copy of libukcprog. This is available as a seperate download. All files updated accordingly to make this version 1.5.4.
#	User	Rev	Content
1	tdb	1.1	/* ip.c - map hostnames */
2
3			/* Copyright 1992 Mark Russell, University of Kent at Canterbury.
4			*
5			* You can do what you like with this source code as long as
6			* you don't try to make money out of it and you include an
7			* unaltered copy of this message (including the copyright).
8			*/
9
10	tdb	1.2	char ukcprog_ip_sccsid[] = "$Id: ip.c,v 1.1 2002/03/08 14:37:29 tdb Exp $ UKC";
11	tdb	1.1
12			#undef _POSIX_SOURCE
13
14			#ifndef MSDOS
15			#include <sys/types.h>
16			#else
17			#include <sys/tk_types.h>
18			#endif
19			#include <sys/socket.h>
20			#include <netinet/in.h>
21			#include <netdb.h>
22
23			#include <stdlib.h>
24			#include <string.h>
25			#include <stdio.h>
26
27			#include "ukcprog.h"
28
29			/* Map a hostname to an IP address. The address is returned in network
30			* byte order. Return 0 for success, -1 and an error message on failure.
31			*
32			* If the hostname looks like an IP quad we convert that to an IP address.
33			*/
34			int
35			get_host_addr(hostname, p_addr)
36			const char *hostname;
37			struct in_addr *p_addr;
38			{
39			struct hostent *h;
40			int b3, b2, b1, b0;
41			char c;
42
43			if (sscanf(hostname, "%d.%d.%d.%d%c", &b3, &b2, &b1, &b0, &c) == 4) {
44			unsigned long val;
45
46			val = (b3 << 24) \| (b2 << 16) \| (b1 << 8) \| b0;
47			p_addr->s_addr = htonl(val);
48			return 0;
49			}
50
51			if ((h = gethostbyname(hostname)) == NULL) {
52			errf("Can't find address of %s", hostname);
53			return -1;
54			}
55
56			if (h->h_addrtype != AF_INET) {
57			errf("%s has non-IP address (addrtype=%d)",
58			hostname, h->h_addrtype);
59			return -1;
60			}
61
62			memcpy((char )p_addr, (char )h->h_addr_list[0], sizeof(*p_addr));
63			return 0;
64			}
65
66			/* Map a service name to a port number in network byte order.
67			* If the service name looks like a number we return that.
68			*/
69			int
70			get_service_port(servname, p_port)
71			const char *servname;
72			int *p_port;
73			{
74			struct servent *sp;
75			char *endstr;
76			unsigned short hport;
77
78			hport = strtol(servname, &endstr, 0);
79			if (endstr != servname && *endstr == '\0') {
80			*p_port = htons(hport);
81			return 0;
82			}
83
84			if ((sp = getservbyname(servname, "tcp")) == NULL) {
85			errf("Unknown service `%s'", servname);
86			return -1;
87			}
88
89			*p_port = sp->s_port;
90
91			return 0;
92			}