/*

 * Copyright (c) 1983, 1993

 *	The Regents of the University of California.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 4. Neither the name of the University nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 *	@(#)talkd.h	8.1 (Berkeley) 6/2/93

 */

#ifndef _PROTOCOLS_TALKD_H

#define	_PROTOCOLS_TALKD_H 1

/*

 * This describes the protocol used by the talk server and clients.

 *

 * The talk server acts a repository of invitations, responding to

 * requests by clients wishing to rendezvous for the purpose of

 * holding a conversation.  In normal operation, a client, the caller,

 * initiates a rendezvous by sending a CTL_MSG to the server of

 * type LOOK_UP.  This causes the server to search its invitation

 * tables to check if an invitation currently exists for the caller

 * (to speak to the callee specified in the message).  If the lookup

 * fails, the caller then sends an ANNOUNCE message causing the server

 * to broadcast an announcement on the callee's login ports requesting

 * contact.  When the callee responds, the local server uses the

 * recorded invitation to respond with the appropriate rendezvous

 * address and the caller and callee client programs establish a

 * stream connection through which the conversation takes place.

 */

#include <sys/types.h>

#include <sys/socket.h>

#include <stdint.h>

#include <bits/types/struct_osockaddr.h>

/*

 * Client->server request message format.

 */

typedef struct {

	unsigned char	vers;	/* protocol version */

	unsigned char	type;	/* request type, see below */

	unsigned char	answer;	/* not used */

	unsigned char	pad;

	uint32_t id_num;	/* message id */

	struct	osockaddr addr;		/* old (4.3) style */

	struct	osockaddr ctl_addr;	/* old (4.3) style */

	int32_t	pid;		/* caller's process id */

#define	NAME_SIZE	12

	char	l_name[NAME_SIZE];/* caller's name */

	char	r_name[NAME_SIZE];/* callee's name */

#define	TTY_SIZE	16

	char	r_tty[TTY_SIZE];/* callee's tty name */

} CTL_MSG;

/*

 * Server->client response message format.

 */

typedef struct {

	unsigned char	vers;	/* protocol version */

	unsigned char	type;	/* type of request message, see below */

	unsigned char	answer;	/* response to request message, see below */

	unsigned char	pad;

	uint32_t	id_num;	/* message id */

	struct	osockaddr addr;	/* address for establishing conversation */

} CTL_RESPONSE;

#define	TALK_VERSION	1		/* protocol version */

/* message type values */

#define LEAVE_INVITE	0	/* leave invitation with server */

#define LOOK_UP		1	/* check for invitation by callee */

#define DELETE		2	/* delete invitation by caller */

#define ANNOUNCE	3	/* announce invitation by caller */

/* answer values */

#define SUCCESS		0	/* operation completed properly */

#define NOT_HERE	1	/* callee not logged in */

#define FAILED		2	/* operation failed for unexplained reason */

#define MACHINE_UNKNOWN	3	/* caller's machine name unknown */

#define PERMISSION_DENIED 4	/* callee's tty doesn't permit announce */

#define UNKNOWN_REQUEST	5	/* request has invalid type value */

#define	BADVERSION	6	/* request has invalid protocol version */

#define	BADADDR		7	/* request has invalid addr value */

#define	BADCTLADDR	8	/* request has invalid ctl_addr value */

/*

 * Operational parameters.

 */

#define MAX_LIFE	60	/* max time daemon saves invitations */

/* RING_WAIT should be 10's of seconds less than MAX_LIFE */

#define RING_WAIT	30	/* time to wait before resending invitation */

#endif /* protocols/talkd.h */