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/*
* Copyright (c) 1997 Loughborough University
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the LUTCHI Research
* Centre at Loughborough University.
* 4. Neither the name of the University nor of the Centre may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY 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 UNIVERSITY 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.
*/
/*
* File: db.h
*
* Description: Whiteboard history database definitions.
*
* J.C.Highfield, 4/97.
*
*/
#ifndef DB_H
#define DB_H
#include "wb.h"
/*
* The whiteboard uses a database of draw history per page.
*
* It also has several queues:
* an outgoing draw command queue (bandwidth limited)
* a correction-request queue (timer & bandwidth limited)
* (requests are cancelled if identical requests are seen).
* a correction-reply queue (timer & bandwidth limited)
* (replies are cancelled if identical replies are seen).
*
*/
/* A list of pages... */
struct page
{
long page_number;
unsigned long creator_ip;
long seq_num_max;
struct page *next;
struct page *prev;
struct writer *writers;
struct action *actions;
};
/* each page has a list of writers... */
struct writer
{
unsigned long writer_ip;
unsigned long seq_num_max;
struct writer *next;
struct writer *prev;
};
/* and a (combined) list of what they wrote... */
struct action
{
uint32 timestamp;
unsigned long writer_ip;
unsigned long seq_num;
struct action *next;
struct action *prev;
struct pk_draw_msg *message;
};
/*
* Queue stuff.
*
*/
enum
{
Q_DRAW_MSG = 0x0001,
Q_STATE = 0x0002,
Q_REPAIR = 0x0003,
Q_REQUEST = 0x0004,
Q_REPORT = 0x0005,
Q_ASKPAGE = 0x0006
};
struct mqueue
{
int type;
int size;
int delay;
struct message *data;
struct mqueue *next;
};
/*
* List of Senders stuff.
*
*/
#define SENDER_NAME_LENGTH 32
struct sender
{
uint32 sender_ip;
uint32 last_sent;
uint32 last_seen;
uint32 last_drawn;
char name[SENDER_NAME_LENGTH];
struct sender *next;
};
#endif
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