/*

 * Copyright (c) 1996,1999 by Internet Software Consortium.

 *

 * 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.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS

 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES

 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE

 * CONSORTIUM 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.

 */

#include <sys/types.h>

#include <sys/socket.h>

#include <netinet/in.h>

#include <arpa/inet.h>

#include <errno.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#ifdef SPRINTF_CHAR

# define SPRINTF(x) strlen(sprintf/**/x)

#else

# define SPRINTF(x) ((size_t)sprintf x)

#endif

static char *	inet_net_ntop_ipv4 (const u_char *src, int bits,

				    char *dst, size_t size) __THROW;

/*

 * char *

 * inet_net_ntop(af, src, bits, dst, size)

 *	convert network number from network to presentation format.

 *	generates CIDR style result always.

 * return:

 *	pointer to dst, or NULL if an error occurred (check errno).

 * author:

 *	Paul Vixie (ISC), July 1996

 */

char *

inet_net_ntop (int af, const void *src, int bits, char *dst, size_t size)

{

	switch (af) {

	case AF_INET:

		return (inet_net_ntop_ipv4(src, bits, dst, size));

	default:

		__set_errno (EAFNOSUPPORT);

		return (NULL);

	}

}

/*

 * static char *

 * inet_net_ntop_ipv4(src, bits, dst, size)

 *	convert IPv4 network number from network to presentation format.

 *	generates CIDR style result always.

 * return:

 *	pointer to dst, or NULL if an error occurred (check errno).

 * note:

 *	network byte order assumed.  this means 192.5.5.240/28 has

 *	0b11110000 in its fourth octet.

 * author:

 *	Paul Vixie (ISC), July 1996

 */

static char *

inet_net_ntop_ipv4 (const u_char *src, int bits, char *dst, size_t size)

{

	char *odst = dst;

	char *t;

	u_int m;

	int b;

	if (bits < 0 || bits > 32) {

		__set_errno (EINVAL);

		return (NULL);

	}

	if (bits == 0) {

		if (size < sizeof "0")

			goto emsgsize;

		*dst++ = '0';

		size--;

		*dst = '\0';

	}

	/* Format whole octets. */

	for (b = bits / 8; b > 0; b--) {

		if (size < sizeof "255.")

			goto emsgsize;

		t = dst;

		dst += SPRINTF((dst, "%u", *src++));

		if (b > 1) {

			*dst++ = '.';

			*dst = '\0';

		}

		size -= (size_t)(dst - t);

	}

	/* Format partial octet. */

	b = bits % 8;

	if (b > 0) {

		if (size < sizeof ".255")

			goto emsgsize;

		t = dst;

		if (dst != odst)

			*dst++ = '.';

		m = ((1 << b) - 1) << (8 - b);

		dst += SPRINTF((dst, "%u", *src & m));

		size -= (size_t)(dst - t);

	}

	/* Format CIDR /width. */

	if (size < sizeof "/32")

		goto emsgsize;

	dst += SPRINTF((dst, "/%u", bits));

	return (odst);

 emsgsize:

	__set_errno (EMSGSIZE);

	return (NULL);

}