rtai_functions.c

The OpenGPSRec receiver software runs on the real time operating system RTAI-Linux. It compiles with

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <time.h>
#include <assert.h>
#include <unistd.h>
#include <curses.h>

#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>

#include <fcntl.h>
#include <signal.h>

#include "../include/port.h"
#include "../include/ogr_defines.h"
#include "../include/ogr_structs.h"

#define KEEP_STATIC_INLINE //for nam2num macros
#include <rtai_shm.h>

#include "defines.h"
#include "globals.h"
#include "rtai_functions.h"

// TASK *Task;


//------------------------------------------------------------------------------
//  cleanup
//  
// De-allocates memory
//
void cleanup( void) 
{


  if ( Chn_RBuf)
    rtai_free( nam2num( SHM_CHN_RBUF), (void*) Chn_RBuf);

#if 0
  if ( corr)
    rtai_free( SHM_CHANNEL, (void*) corr);
  if ( param)
    rtai_free( SHM_CTRLPARMS, (void*) param);
  if ( chanBuf)
    rtai_free( SHM_BUF, (void*) chanBuf);
  if ( Task)
    rtai_free( SHM_TASK, (void*) Task);
#endif

  return;
}

#if 0
//------------------------------------------------------------------------------
// numTasks
//
// Returns the number of tasks stored in the Task[] struct.
//
int numTasks(void) 
{
  int i;

  for (i=0; i < MAX_TASKS; i++) 
  {
    if (strcmp("",Task[i].name)==0) /* empty spot */
      return i;
  }
  /* Not found */
  return FALSE;
}
#endif

//------------------------------------------------------------------------------
//  chanBufRead 
//  
// Returns the CHANNEL data at index (given ch) 
//
// index: 0 (newest data)
// index: CHAN_RING_BUF_SIZE-1 (oldest data)
//
CHN_INFO chanBufRead( INT16 chHeadNow, INT16 index) 
{

// do a few sanity checks
  if ((chHeadNow < 0) || (chHeadNow >= CHN_RBUF_LEN)) 
  {
    printf( "Error, chanHeadNow [%d] out of bounds\n", chHeadNow);
    exit( 0);
  }

  if ((index < 0) || (index >= CHN_RBUF_LEN)) 
  {
    printf( "Error, index [%d] out of bounds\n", index);
    exit( 0);
  }

/* Calculate correct index (ring buffer
 * wraps at 0 and CHN_RBUF_LEN
 */
  if ((chHeadNow-index) < 0) 
    index = CHN_RBUF_LEN + (chHeadNow-index);
  else 
    index = chHeadNow-index;

//  printf("rtai_fun: index = %d\n",index);

  index = max( 0, min( CHN_RBUF_LEN-1, index));

//  return chanBuf[index].chan[ch];

//  printf( "Chn_RBuf->chan[%d].ch = %d \n", index, Chn_RBuf->chan[index].ch);

#if 0
  {
    int i;
    for (i=0;i<100;i++)
    printf( "Chn_RBuf->chan[%d].ch = %d \n", i, Chn_RBuf->chan[i].ch);
  }  
#endif

  return Chn_RBuf->chan[index];
}

//------------------------------------------------------------------------------
//  chanBufReadRev 
//  
// Returns the CHANNEL data at index (given ch) 
//
// index: 0 (newest data)
// index: CHAN_RING_BUF_SIZE-1 (oldest data)
//
CHN_INFO chanBufReadRev( INT16 chHeadNow, INT16 index) 
{

// do a few sanity checks
  if ((chHeadNow < 0) || (chHeadNow >= CHN_RBUF_LEN)) 
  {
    printf( "Error, chanHeadNow [%d] out of bounds\n", chHeadNow);
    exit( 0);
  }

  if ((index < 0) || (index >= CHN_RBUF_LEN)) 
  {
    printf( "Error, index [%d] out of bounds\n", index);
    exit( 0);
  }

  index = max( 0, min( CHN_RBUF_LEN-1, index));

  return Chn_RBuf->chan[index];
}

/*******************************************************************************
FUNCTION init_user()
RETURNS  None.

PARAMETERS None.

PURPOSE
  user land initialization

WRITTEN BY
  G. Beyerle, S. Esterhuizen

*******************************************************************************/
void init_user( void) 
{

#if 0
//  init shared memory
  corr = (CHANNEL_RBUF*) rtai_malloc( SHM_CHANNEL, sizeof( CHANNEL_RBUF));
  if ( !corr)
  { 
    printf( "rtai_malloc() failed in init_user().\n");
    exit(-1);
  }
#endif

//  init ring buffer
  Chn_RBuf = (CHN_RBUF*) rtai_malloc( nam2num( SHM_CHN_RBUF), 
    sizeof( CHN_RBUF));
  if ( !Chn_RBuf)
  { 
    printf( "rtai_malloc(SHM_CHN_RBUF,%d) failed in init_user().\n", 
      sizeof( CHN_RBUF));
    exit(-1);
  }

#if 0
  param = (CTRLPARMS*) rtai_malloc( SHM_CTRLPARMS, sizeof( CTRLPARMS));
  if ( !param)
  { 
    printf( "rtai_malloc() failed in main().\n");
    exit(-1);
  }
#endif

#if 0
  Task = (TASK*) rtai_malloc( SHM_TASK, sizeof( TASK)*MAX_TASKS);
  if ( !Task)
  { 
    printf( "rtai_malloc() failed in main().\n");
    exit(-1);
  }
#endif

  return;
}