/*      $OpenBSD: inet_neta.c,v 1.7 2005/08/06 20:30:03 espie Exp $     */

/*
 * Copyright (c) 1996 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>

/*
 * char *
 * inet_neta(src, dst, size)
 *      format an in_addr_t network number into presentation format.
 * return:
 *      pointer to dst, or NULL if an error occurred (check errno).
 * note:
 *      format of ``src'' is as for inet_network().
 * author:
 *      Paul Vixie (ISC), July 1996
 */
char *
inet_neta(in_addr_t src, char *dst, size_t size)
{
        char *odst = dst;
        char *ep;
        int advance;

        if (src == 0x00000000) {
                if (size < sizeof "0.0.0.0")
                        goto emsgsize;
                strlcpy(dst, "0.0.0.0", size);
                return dst;
        }
        ep = dst + size;
        if (ep <= dst)
                goto emsgsize;
        while (src & 0xffffffff) {
                u_char b = (src & 0xff000000) >> 24;

                src <<= 8;
                if (b || src) {
                        if (ep - dst < sizeof "255.")
                                goto emsgsize;
                        advance = snprintf(dst, ep - dst, "%u", b);
                        if (advance <= 0 || advance >= ep - dst)
                                goto emsgsize;
                        dst += advance;
                        if (src != 0L) {
                                if (dst + 1 >= ep)
                                        goto emsgsize;
                                *dst++ = '.';
                                *dst = '\0';
                        }
                }
        }
        return (odst);

 emsgsize:
        errno = EMSGSIZE;
        return (NULL);
}