command.c

This a framework to test new ideas in transmission technology. Actual development is a LDPC-coder in

/***************************************************************************
           command.c  -  A fifo-interface to the channel-server
                            -------------------
    begin                :  2003
    authors              :  Linus Gasser
    emails               :  [e-mail]
 ***************************************************************************/

/***************************************************************************
                                 Changes
                                 -------
 date - name - description
 03/01/20 - ineiti - begin
 
 **************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/


/**
 * It opens two FIFOs: one for commands, and one for results. They
 * are called "cmd" and "res" respectivley. The commands you can send:
 *
 * - STATS - returns # of channels
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <pthread.h>
#include "command.h"
#include "server.h"
#include "system.h"
#include "debugging.h"

#define DBG_LVL 3


pthread_t thr_getFifo;

void *getFifo( void *arg ) {
  FILE *cmd, *result;
  char *str;
  int ch, i, j, nbr;

  mkfifo( "cmd", S_IRWXU );
  mkfifo( "result", S_IRWXU );

  if ( ( cmd = fopen( "cmd", "r" ) ) < 0 ) {
    PR_DBG( 0, "Couldn't open cmd\n" );
    return NULL;
  }

  PR_DBG( 4, "Opened cmd\n" );

  if ( ( result = fopen( "result", "w" ) ) < 0 ) {
    PR_DBG( 0, "Couldn't open result\n" );
    fclose( cmd );
    return NULL;
  }

  PR_DBG( 4, "Opened result\n" );

  while (1) {
    if ( ( fscanf( cmd, "%as\n", &str ) > 0 ) ) {
      PR_DBG( 4, "Got CMD: %s\n", str );
      if ( !strcmp( str, "STATS" ) ) {
        ch = ( nbr_clients > 1 ) ? nbr_clients - 1 : 0;
        PR_DBG( 4, "STATS: %i %i\n", ch, CHANNEL_LENGTH );
        fprintf( result, "%i %i\n", ch, CHANNEL_LENGTH );
      } else if ( !strcmp( str, "CHANNEL" ) ) {
        fscanf( cmd, "%i %i", &ch, &nbr );
        PR_DBG( 4, "CHANNEL %i, %i: ", ch, nbr );
        for ( i=0; i<nbr; i++ ) {
	  for( j = 0; j < nbr; j++){
	    fscanf( cmd, "%lf", &channel_tap[ ch ][ i ][ j ] );
	    PR_DBG_CL( 4, "%f ", channel_tap[ ch ][ i ][ j ] );
	  }
        }
        PR_DBG_CL( 4, "\n" );
        fprintf( result, "OK\n" );
      } else {
        PR_DBG( 0, "Error, couldn't recoginze CMD %s", str );
      }
    } else {
      fclose( cmd );
      fclose( result );
      PR_DBG( 4, "Fifo closed. Re-opening it\n" );
      cmd = fopen( "cmd", "r" );
      PR_DBG( 4, "ReOpened cmd\n" );
      result = fopen( "result", "w" );
      PR_DBG( 4, "ReOpened result\n" );
    }
  }
  fclose( cmd );
  fclose( result );
}



int init_command() {

  pthread_create( &thr_getFifo, NULL, getFifo, NULL );

  return 0;
}


void exit_command() {
  pthread_cancel( thr_getFifo );
}