/* @(#)bindresvport.c	1.1 87/11/04 3.9 RPCSRC */

/*
	$Disclaimer: 
 * Permission to use, copy, modify, and distribute this software and its 
 * documentation for any purpose is hereby granted without fee, 
 * provided that the above copyright notice appear in all copies and that 
 * both that copyright notice, this permission notice, and the following 
 * disclaimer appear in supporting documentation, and that the names of 
 * IBM, Carnegie Mellon University, and other copyright holders, not be 
 * used in advertising or publicity pertaining to distribution of the software 
 * without specific, written prior permission.
 * 
 * IBM, CARNEGIE MELLON UNIVERSITY, AND THE OTHER COPYRIGHT HOLDERS 
 * DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING 
 * ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.  IN NO EVENT 
 * SHALL IBM, CARNEGIE MELLON UNIVERSITY, OR ANY OTHER COPYRIGHT HOLDER 
 * BE LIABLE FOR ANY SPECIAL, 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.
 *  $
*/

#ifndef NORCSID
#define NORCSID
static char rcsid[]="$Header: /afs/cs.cmu.edu/project/atk-dist/auis-6.3/contrib/mit/fxlib/rpc3.9/rpc/RCS/bindresvport.c,v 1.3 1992/12/15 21:53:39 rr2b R6tape $";
#endif

/*
 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
 * unrestricted use provided that this legend is included on all tape
 * media and as a part of the software program in whole or part.  Users
 * may copy or modify Sun RPC without charge, but are not authorized
 * to license or distribute it to anyone else except as part of a product or
 * program developed by the user.
 * 
 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
 * 
 * Sun RPC is provided with no support and without any obligation on the
 * part of Sun Microsystems, Inc. to assist in its use, correction,
 * modification or enhancement.
 * 
 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
 * OR ANY PART THEREOF.
 * 
 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
 * or profits or other special, indirect and consequential damages, even if
 * Sun has been advised of the possibility of such damages.
 * 
 * Sun Microsystems, Inc.
 * 2550 Garcia Avenue
 * Mountain View, California  94043
 */
#if !defined(lint) && defined(SCCSIDS)
static  char sccsid[] = "@(#)bindresvport.c 1.6 87/09/23 SMI";
#endif

/*
 * Copyright (c) 1987 by Sun Microsystems, Inc.
 */

#include <sys/types.h>
#include <sys/errno.h>
#include <sys/socket.h>
#include <netinet/in.h>

/*
 * Bind a socket to a privileged IP port
 */
bindresvport(sd, sin)
	int sd;
	struct sockaddr_in *sin;
{
	int res;
	static short port;
	struct sockaddr_in myaddr;
	extern int errno;
	int i;

#define STARTPORT 600
#define ENDPORT (IPPORT_RESERVED - 1)
#define NPORTS	(ENDPORT - STARTPORT + 1)

	if (sin == (struct sockaddr_in *)0) {
		sin = &myaddr;
		bzero(sin, sizeof (*sin));
		sin->sin_family = AF_INET;
	} else if (sin->sin_family != AF_INET) {
		errno = EPFNOSUPPORT;
		return (-1);
	}
	if (port == 0) {
		port = (getpid() % NPORTS) + STARTPORT;
	}
	for (i = 0; i < NPORTS; i++) {
		sin->sin_port = htons(port++);
		if (port > ENDPORT) {
			port = STARTPORT;
		}
		res = bind(sd, sin, sizeof(struct sockaddr_in));
		if (res == 0) {
			return (0);
		}
		if ((res < 0) && (errno == EACCES)) {
			return (-1);
		}
	}
	return (-1);
}