#ifndef __PIPE_SYNC_H__
#define __PIPE_SYNC_H__

#include <unistd.h>


// change producer-consumer sync mechanism to that of ioxos example
#define IOXOSSYNC 1


// enable this define for additional seralization for each io
//#define USE_SERIALIZE_IO 1

// usecs for wait poll loop
//#define PIPESYNC_SLEEP 10000

#define PIPESYNC_SLEEP 1

// seconds timeout for wait
#define PIPESYNC_TIMEOUT 300

// number of loop cycles for timeout
#define PIPESYNC_MAXLOOP PIPESYNC_TIMEOUT * 1000000 / PIPESYNC_SLEEP


#ifdef USE_SERIALIZE_IO
// taken from vetar driver/ipv - does this change anything?
#define SERIALIZE_IO __asm__ volatile ("eieio")
#else
#define SERIALIZE_IO ;
#endif

// test: only serialize access to com structures
#define SERIALIZE_COM __asm__ volatile ("eieio")


#ifdef IOXOSSYNC

long readcounter;
long writecounter;

#endif




/**
 * communication structure to be put at begin of pipe memory.
 * JAM 30-oct-2020
 */
typedef volatile struct
{
  volatile int canread;  // if 1, producer has provided data to read, otherwise consumer waits
  volatile int canwrite; // if 1, consumer has processed most recent block and producer can send another
  volatile int counter;  // number of pipe cycles processed. can be used to modify data content

} s_pipe_sync;


/** wait until reading is allowed. Returns negative value in case of timeout*/
int f_wait_read(s_pipe_sync* com);

/** wait until writing is allowed. Returns negative value in case of timeout*/
int f_wait_write(s_pipe_sync* com);

/** set pipe read state to allow (1) or suspend (0)*/
void f_set_read(s_pipe_sync* com, int on);

/** set pipe write state to allow (1) or suspend (0)*/
void f_set_write(s_pipe_sync* com, int on);


#endif