xref: /freebsd/lib/libc/inet/inet_neta.c (revision dc36d6f9bb1753f3808552f3afd30eda9a7b206a)

/*-
 * SPDX-License-Identifier: ISC
 *
 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
 * 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 ISC DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC 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 "port_before.h"

#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 "port_after.h"

#ifdef SPRINTF_CHAR
# define SPRINTF(x) strlen(sprintf/**/x)
#else
# define SPRINTF(x) ((size_t)sprintf x)
#endif

/*%
 * 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 *tp;

	while (src & 0xffffffff) {
		u_char b = (src & 0xff000000) >> 24;

		src <<= 8;
		if (b) {
			if (size < sizeof "255.")
				goto emsgsize;
			tp = dst;
			dst += SPRINTF((dst, "%u", b));
			if (src != 0L) {
				*dst++ = '.';
				*dst = '\0';
			}
			size -= (size_t)(dst - tp);
		}
	}
	if (dst == odst) {
		if (size < sizeof "0.0.0.0")
			goto emsgsize;
		strcpy(dst, "0.0.0.0");
	}
	return (odst);

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

/*
 * Weak aliases for applications that use certain private entry points,
 * and fail to include <arpa/inet.h>.
 */
#undef inet_neta
__weak_reference(__inet_neta, inet_neta);

/*! \file */