mdist.h

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/* mdist.h -- core definitions header file
 *  
 * This file is part of 'netcast' program, released under BSD License. 
 * (c) 2001-2002 Stanis砤w Pa秌o <[e-mail]>. All rights reserved.   
 */

#ifndef _MDIST_MDIST_H
#define _MDIST_MDIST_H

#include <unistd.h>
#include <netinet/ip.h>
#include <netinet/udp.h>

#include "debug.h"

#define MTU 1500
#define MMSIZE MTU-sizeof(struct iphdr)-sizeof(struct udphdr)
#define MMDSIZ ((MMSIZE-sizeof(struct mdmsg))>>2)<<2
#define ROUND 1024
#define BUFSIZE MMSIZE*ROUND
#define BUFPOS(x) MMSIZE*x

#define DEF_PORT 9876

//! Single message as received from the net
struct mdmsg {
  uint32_t seq;
  uint32_t crc;
  uint16_t siz;
  uint8_t data[0];
};

//! TCP messages

//! Control message
struct mdctl {
  uint32_t blk;              //! Block number
  uint32_t base;             //! Base for packet sequence nums
  uint32_t siz;              //! Block size 
  uint32_t pkt;              //! Number of packets to-be-transmitted
};

#define CLIENT_START 0x1
#define CLIENT_READY 0x2
#define CLIENT_REQ 0x4

//! Client reply
struct mdreq {
  uint32_t ack;              //! Acknowledge block number
  uint32_t rqc;              //! Requested blocks count
};

//! Initial data
struct mdinit {
  struct sockaddr_in group;
};  

extern struct mdmsg *mdbuf[ROUND];
extern struct mdctl mdhead;
extern struct mdinit mdini;

void md_init();
long md_fill(int fd);
long md_flush(int fd);
struct mdmsg *md_put(struct mdmsg *src);
struct mdmsg *md_get(uint32_t seq);


#endif