spread_send.c

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

/***************************************************************************
 *    spread_send.c  -  Spread the signal
 *                           -------------------
 *   begin                :  2003
 *   authors              :  ineiti
 *   emails               :  [e-mail]
 ***************************************************************************/

/***************************************************************************
 *                                Changes
 *                                -------
 * date - name - description
 * 03/01/29 - ineiti - begin
 * 04/01/07 - ineiti - took away some inputs
 * 04/03/05 - ineiti - adjusted description
 * 04/03/29 - ineiti - adjusted context->private_data = swr_malloc declaration
 *
 **************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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 module spreads every input-symbol by a config->factor. It does
 * this according to the config->sequence, which defines the
 * spreading-sequence. So, if config->sequence is 0x55, the spreading-
 * sequence is -1 +1 -1 +1 -1 +1 -1 +1
 */
#include "spc.h"
#include "spread.h"

#define DBG_LVL 0


typedef struct {
  // The factor is the spreading-sequence length
  int factor; // 8
  // Each bit is one spreading-symbol. 0 is -1, 1 is 1...
  int sequence; // 0x0f
}
config_t;

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

typedef struct {
  int factor;
  int table[ MAX_SPREAD_LEN ];
}
private_t;


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

int send_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

  // Let's define a spreading-sequence of length 8
  config->factor = 8;
  // The spreading sequence is -1 -1 -1 -1 1 1 1 1
  config->sequence = 0x0f;

  // 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
}


/*
 * To configure the inputs
 * this is called when the output-sizes change.
 */
int send_configure_inputs( swr_sdb_t *context ) {
  // Definition of variables - don't touch
  config_t *config;
  swr_sdb_get_config_struct( context->id, (void**)&config );

  size_in( 0 ) = size_out( 0 ) / config->factor;
  PR_DBG( 3, "Input-size: %i\n", size_in(0) );

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


/*
 * To configure the outputs
 * this is called when the input-sizes change
 */
int send_configure_outputs( swr_sdb_t *context ) {
  // Definition of variables - don't touch
  config_t *config;
  swr_sdb_get_config_struct( context->id, (void**)&config );

  size_out( 0 ) = size_in( 0 ) * config->factor;
  PR_DBG( 3, "Output-size: %i\n", size_out(0) );

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


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

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

  if ( config->factor < 1 ){
    config->factor = 1;
  }
  for ( i=0, bits=config->sequence; i<config->factor; i++, bits /= 2 ) {
    private->table[ i ] = ( bits & 1 ) * 2 - 1;
    PR_DBG( 2, "table[%i] = %i\n", i, private->table[i] );
  }
  private->factor = config->factor;

  // 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 send_pdata( swr_sdb_t *context ) {
  // Definition of variables - don't touch
  stats_t *stats;
  SYMBOL_COMPLEX *in, *out;
  int i,j;

  in = buffer_in(0);
  out = buffer_out(0);

  // Spread the symbols
  for ( i=0; i<size_in(0); i++ ) {
    for ( j=0; j<private->factor; j++ ) {
      out->real = in->real * private->table[j];
      out->imag = in->imag * private->table[j];
      PR_DBG( 4, "(%5i,%5i)->(%5i,%5i)\n", 
	      in->real, in->imag, out->real, out->imag );
      out++;
    }
    in++;
  }

  // Make a nice tail with the last symbol
  for ( i=0; i<size_out(0) - size_in(0) * private->factor; i++ ) {
    out[i] = out[-1];
  }

  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);
}


/*
 * This is the `destructor'.
 */
int send_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 send_id;
int send_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( 1, 1, 2, 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_INT( "factor" );
  UM_CONFIG_INT( "sequence" );
  /**
   * 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}, 0 );
   * UM_OUTPUT( SIG_{U8,SYMBOL_{S16,COMPLEX,MMX},SAMPLE_S12,S32}, 0 );
   */
  UM_INPUT( SIG_SYMBOL_COMPLEX, 0 );
  UM_OUTPUT( SIG_SYMBOL_COMPLEX, 0 );

  // Initialise the callback-functions. Delete the ones you don't use
  desc->fn_init              = send_init;
  desc->fn_reconfigure       = send_reconfig;
  desc->fn_process_data      = send_pdata;
  desc->fn_configure_inputs  = send_configure_inputs;
  desc->fn_configure_outputs = send_configure_outputs;
  desc->fn_finalize          = send_finalize;

  // And register the module in the SPM. Change the name!
  send_id = swr_cdb_register_spc( &desc, "spread" );
  if ( send_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 send_module_exit( void ) {
  PR_DBG( 4, "Freeing id: %i\n", send_id );
  if ( swr_cdb_unregister_spc( send_id ) < 0 ) {
    PR_DBG( 0, "Still in use somewhere\n" );
  }
}