test_math.c

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

/***************************************************************************
              test_math.c  -  Does math run in kernel-mode?
                            -------------------
    begin                :  2003
    authors              :  ineiti
    emails               :  [e-mail]
 ***************************************************************************/

/***************************************************************************
                                 Changes
                                 -------
 date - name - description
 2003-02-28 - ineiti - begin
 04/03/03 - ineiti - added a small 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.                                   *
 *                                                                         *
 ***************************************************************************/

char desc[] =
"Description:\n"
"Just verify whether the math works. Mostly interesting in kernel-mode,\n"
"where one isn't supposed to use maths. But with RTLinux, it works,\n"
"nevertheless...\n"
"The calculation is asin( 100/100 ) = 157/100\n\n";

#include "spc.h"
#include "std.h"
#include <math.h>

#define DBG_LVL 4


void *start_it( void *arg ) {
  float x, y;

  x = 1.;
  y = asin( x );
  // We can't print floats or doubles in the kernel, so we just print
  // a multiple of it...
  PR_DBG( 4, "asin(%i/100)=%i/100\n", (int)( x * 100 ), (int)( y * 100 ) );

  return 0;
}

swr_spc_id_t spm_id;

struct thread start;
/**
 * This function is called upon "insmod" and is used to register the
 * different parts of the module to the SPM.
 */
int um_module_init(void) {

  PR_CL( desc );
  if ( swr_thread_init( &start, start_it, NULL ) < 0 )
    goto first_no_stack;
  return 0;

first_no_stack:
  PR_DBG( 0, "Couldn't allocate stack\n" );
  return -1;
}

void um_module_exit( void ) {

  swr_thread_free( &start, NULL );

}


module_init( um_module_init );
module_exit( um_module_exit );