mux.h

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/* MUX.H */

#ifndef _MUX_H_
#define _MUX_H_

#include "al_sending.h"
#include "al_receiving.h"
#include "channel.h"
#include "mux.h"
#include "med.h"
#include "bch.h"


/* new stuff */

#define MUX_TABLE_SIZE  16

#define DEF_MUX_HEADER 1
#define DEF_MUX_SYNC_FLAG 32
#define DEF_MUX_SYNC_THRESH 28

#define DEF_MUX_LEVEL 1


#define DEF_PAYLOAD_MIN 1
#define DEF_PAYLOAD_MAX 128

#define DEF_HEADER_CODE BCH15_5
#define DEF_USE_MPL 0
#define DEF_MPL_CODE BCH15_11

#define DEF_INFO_FIELD_LENGTH  128    

/* oldjunk */
#define NO_INTERLEAVING   0 
#define BIT_INTERLEAVING  1
#define BYTE_INTERLEAVING 2

#define DEF_HEADER_MC_LENGTH    4
#define DEF_HEADER_CRC_LENGTH   3

#define MAX_AL_SENDERS 10
#define MAX_AL_RECEIVERS 10
/* end oldjunk */


/*****************************************************************************
 * Parameters shared between MUX and DEMUX                                   *
 *****************************************************************************/

typedef struct {
  /*
   * Synchronization word length
   */
  int sync_flag_length;    /* 0, 8, 16, 24, 32 bits.  */

  int use_double_flag;     /* for level2, 16 bit flag, will double it */

  int sync_threshold;      /* bits required to have a valid sync flag */

  int mpl_sync_threshold;  /* threshold when using mpl from previous packet */
  bch_type header_code;

  int use_mpl;
  bch_type mpl_code;

  int payload_min;
  int payload_max;

  int info_field_length;                         /* changes each packet . */

  /*
   * The Multiplex Table.
   */ 
  mux_table_entry mux_table[MUX_TABLE_SIZE];         /* table of MultiplexEntryDescriptors */
  int mux_table_size;                 /* number of entries in mux table */

  float **mt_ratios;                  /* ratio of bytes to total bytes
                                         per channel per multiplex code */

  int **mt_bytes;                     /* number of bytes to send per channel 
                                         per multiplex code */

  char stat_file[MAX_FILENAME_LENGTH];  /* filename for outputting statistics */

  int level;                          /* level 1 or level 2 */
  
  int mpl_t;                          /* error correction capability of mpl bch */
  int head_t;                         /* error correction capability of hdr bch */
} mux_parameters;


typedef struct {
  char name[41];        /* A label like "Remote Mux" or "Local Mux" */

  /* Params shared with corresponding DEMUX */
  mux_parameters *params;

  /************************************************************************** 
   * MUX Specific Parameters                                                *
   **************************************************************************/

  al_sending_entity *al_senders[MAX_AL_SENDERS]; /* read MUX-SDU's from here*/

  int num_al_senders;

  channel *output;                       /* write MUX-PDUs here */

  int wait_time;                    /* time to wait between packets. */

  int packetsSent;                  /* number of packets it has sent */
} mux;


/* Function Prototypes */

mux_parameters *new_mux_parameters(char *name);
/* 
 * This function is defined in muxstuff.c
 */

mux *new_mux(char *name);
/*
 * mallocs a new mux structure
 */

static int bytes_ok(int mt_bytes[], int buffer_bytes[], int d, mux *m);
     /*
      * Returns 1 iff for i=0, i<d, mt_bytes[i] <= buffer_bytes[i]
      *           also, number of channels described in the MED must
      *           equal the number of channels.  Ie. if you only
      *           have LCN0 and LCN1, and your MED is
      *           {LCN1 RC 10, LCN2 RC UCF} this function returns 0.
      *
      * Should be used like this:
      *
      * if (bytes_ok(mt_bytes, al_buffer, num_channels, m);
      */

float ratio_difference(float a[], float b[], int d);
     /*
      * Computes the scalar difference between a[] and b[]
      * (i.e. sum(i=0, d-1, (abs(b[i] - a[i]))).
      *
      * Should be used like this:
      *
      * diff = compute_difference(mt_ratios, al_ratios, num_channels);
      */

static void print_int(int x);
/*
 * Prints a 32-bit representation of an integer
 */

static void set_payload_size(mux *m);
/*
 * sets up a random payload length
 */

void multiplex(mux *m, int num_channels);
/*
 * This is the main mux function
 *   it chooses the best multiplex code based on the buffer
 *   levels, and sends the appropriate mux-pdu structure 
 */

void close_mux(mux *m);
/*
 * prints out the mux stats
 */

#endif

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