rnddouble.c

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

/***************************************************************************
 *    rnddouble.c  -  Module to produce some double randoms
 *                           -------------------
 *   begin                :  2003
 *   authors              :  Linus Gasser
 *   emails               :  [e-mail]
 ***************************************************************************/

/***************************************************************************
 *                                Changes
 *                                -------
 * date - name - description
 * 2003/08/22 - ineiti - begin
 * 04/03/05 - ineiti - adjusted description
 *
 **************************************************************************/

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


/**
 * Generates random numbers with double-precision. The resolution of the
 * random-numbers should be in the range of 2^-32 * range. Two outputs exist:
 * one for real numbers and one for complex numbers. Chose the appropriate
 * one, and the numbers will be calculated for this output.
 */
#include "spc.h"


#define DBG_LVL 4
#define MODULO       2147483647
#define FACTOR       16807
#define LASTXN       127773
#define UPTOMOD     -2836



typedef struct {
  // The random-numbers will be from -range..range
  double range; // 1
  // This gives the range for both the real and complex part. The
  // generated numbers will be 
  // -real( range_complex )..real( range_complex ) +
  // -imag( range_complex )..imag( range_complex ) * I
  double complex range_complex; // 1 + I
  // if the seed < 0, then the random-number generator will be initialised
  // with the time. Else the corresponding seed will be taken for initialisation.
  int seed; // 0
}
config_t;

typedef struct {
  // ADD HERE, int, double or char[128]
}
stats_t;

typedef struct {
  double range;
  double complex range_complex;
  int seed;
}
private_t;


/*
 * The initialisation function, or constructor, 
 * is called the first time this module is instantiated.
 */

int spc_init( swr_sdb_t *context ) {
  // Begin system-definitions {
  config_t *config;
  stats_t *stats;
  MOD_INC_USE_COUNT;
  if ( sizeof( private_t ) > 0 )
    context->private_data = swr_malloc( sizeof( private_t ) );
  swr_sdb_get_config_struct( context->id, (void**)&config );
  swr_sdb_get_stats_struct( context->id, (void**)&stats );
  // } End of system-definitions

  config->range = 1;
  config->range_complex = 1 + I;
  config->seed = 0;

  // Begin system-definitions
  swr_sdb_free_stats_struct( context->id, (void**)&stats );
  swr_sdb_free_config_struct( context->id, (void**)&config );
  return 0;
  // End system-definitions
}


/*
 * Every time modules from the outside change the value of a configuration parameter,
 * this function is called.
 */

int spc_reconfig( swr_sdb_t *context ) {
  // Definition of variables - don't touch
  config_t *config;
  swr_sdb_get_config_struct( context->id, (void**)&config );

  private->range = config->range;
  private->range_complex = config->range_complex;
  if ( config->seed<=0 ) {
    private->seed = (int)get_time_usec()%100000000;
  } else {
    private->seed = config->seed;
  }


  // Definition - don't touch
  swr_sdb_free_config_struct( context->id, (void**)&config );
  return 0;
}


/*
 * This is the function that implements the `main method' of the class
 * Every class has got just ONE method/working-mode.
 */
int spc_pdata( swr_sdb_t *context ) {
  // Definition of variables - don't touch
  stats_t *stats;
  double *out;
  double complex *out2;
  int i;
  int times, rest, prod1, prod2;

  out = buffer_out( 0 );
  for ( i=0; i<size_out(0); i++ ) {
    times    = private->seed / LASTXN;
    rest     = private->seed - times * LASTXN;
    prod1    = times * UPTOMOD;
    prod2    = rest * FACTOR;
    private->seed     = prod1 + prod2;
    if (private->seed < 0)
      private->seed = private->seed + MODULO;
    out[i] = ( private->seed / ( MODULO / 2. ) - 1 ) * private->range;
  }

  PR_DBG( 0, "Going to create %i double complex\n", size_out(1) );
  out2 = buffer_out( 1 );
  for ( i=0; i<size_out(1) * 2; i++ ) {
    times    = private->seed / LASTXN;
    rest     = private->seed - times * LASTXN;
    prod1    = times * UPTOMOD;
    prod2    = rest * FACTOR;
    private->seed     = prod1 + prod2;
    if (private->seed < 0){
      private->seed = private->seed + MODULO;
    }
    if ( i % 2 ){
      out2[i/2] = ( private->seed / ( MODULO / 2. ) - 1 ) * creal( private->range_complex );
    } else {
      out2[i/2] += ( private->seed / ( MODULO / 2. ) - 1 ) * cimag( private->range_complex ) * I;
    }
  }

  swr_sdb_get_stats_struct( context->id, (void**)&stats );
  // Put your code here
  // ADD HERE
  swr_sdb_free_stats_struct( context->id, (void**)&stats );
  return(0);
}


int spc_custom_msg(swr_sdb_t *context, swr_usr_msg_t* msg_data, swr_msgq ret ) {
  spc_pdata( context );
  return 0;
}


/*
 * This is the `destructor'.
 */
int spc_finalize( swr_sdb_t *context ) {
  if ( sizeof( private_t ) > 0 )
    swr_free( private );
  MOD_DEC_USE_COUNT;
  return 0;
}


/*
 * This function is called upon "insmod" and is used to register the
 * different parts of the module to the SPM.
 */
swr_spc_id_t cdb_id;
int spc_module_init(void) {
  swr_spc_desc_t *desc;

  /**
   * Get a description-part from SPM
   * Give the following parameters:
   * Input-ports, output-ports, config-params, stat-params
   */
  desc = swr_spc_get_new_desc( 0, 2, 3, 0 );
  if ( !desc ) {
    PR_DBG( 0, "Can't initialise the module. This is BAD!\n" );
    return -1;
  }

  /**
   * Define the different parts of config and stats. You have to define
   * them in the same order as they appear in the structures. The names
   * can be freely chosen.
   *
   * UM_CONFIG_{INT,DOUBLE,STRING128,POINTER}( "name" );
   * UM_STATS_{INT,DOUBLE,STRING128,POINTER,BLOCK}( "name" );
   */
  UM_CONFIG_DOUBLE( "range" );
  UM_CONFIG_DOUBLE_COMPLEX( "range_complex" );
  UM_CONFIG_INT( "seed" );
  /**
   * The in- and outputs have also to be defined in the right order. First
   * port first. The additional flag is not used yet, but it will...
   *
   * UM_INPUT( SIG_{U8,SYMBOL_{S16,COMPLEX,MMX},SAMPLE_S12,S32,DOUBLE}, 0 );
   * UM_OUTPUT( SIG_{U8,SYMBOL_{S16,COMPLEX,MMX},SAMPLE_S12,S32,DOUBLE}, 0 );
   */
  UM_OUTPUT( SIG_DOUBLE, 0 );
  UM_OUTPUT( SIG_DOUBLE_COMPLEX, 0 );

  // Initialise the callback-functions. Delete the ones you don't use
  desc->fn_init              = spc_init;
  desc->fn_reconfigure       = spc_reconfig;
  desc->fn_process_data      = spc_pdata;
  desc->fn_finalize          = spc_finalize;
  desc->fn_custom_msg = spc_custom_msg;

  // And register the module in the SPM. Change the name!
  cdb_id = swr_cdb_register_spc( &desc, "rnddouble" );
  if ( cdb_id == SWR_SPM_INVALID_ID ) {
    swr_spc_free_desc( desc );
    PR_DBG( 0, "Couldn't register the module!\n" );
    return 1;
  }
  PR_DBG( 4, "Ready\n" );
  return 0;
}


/*
 * This is called upon rmmod
 */
void spc_module_exit( void ) {
  PR_DBG( 4, "Freeing id: %i\n", cdb_id );
  if ( swr_cdb_unregister_spc( cdb_id ) < 0 ) {
    PR_DBG( 0, "Still in use somewhere\n" );
  }
}


module_init( spc_module_init );
module_exit( spc_module_exit );