ab.h

/*
  Implementation of the alternating bit protocol on top of LNP for
  LegOS/BrickOS
  Copyright (C) 2004  Bram De Wachter

  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License
  as published by the Free Software Foundation; either version 2
  of the License, or (at your option) any later version.
  
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  
  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/


/*Alternating Bit Protocol:
  1. use init_AB_protocol(portHandler) to initialize the protocol
  2. use AB_write(message, length) to send a message
*/

#include <lnp/lnp.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <semaphore.h>
#include <time.h>


#define DEBUG     0

#define WRITE_WAIT_TIME  10 

#define WRITE_TIMEOUT    100




#define HEADER_SZ         3

typedef struct message_struct {
  unsigned char* txt;

  unsigned char len;

  sem_t         sem_ack;

  struct message_struct *next;
} msg_s ;


typedef struct site_struct {
  unsigned char id;

  unsigned char status;

  time_t timeout_wait;

  struct site_struct *next;

  msg_s * head;
} site_s ;



unsigned char ab_source;


int ab_awrite(const unsigned char* message, unsigned char length, unsigned char destination);


int ab_swrite(const unsigned char* message, unsigned char length, unsigned char destination);

int init_ab_protocol_8(void (*u_portHandler) (const unsigned char *message, unsigned char length),  
                       unsigned char id);

int init_ab_protocol_16(void (*u_portHandler) (const unsigned char *message, unsigned short length),
                        unsigned char id, unsigned char max_id);

int ab_swrite_16(const unsigned char* message, unsigned short length, unsigned char destination);

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