#include <stdio.h>
#include <stdlib.h>
#include <sys/shm.h>
#include <sys/stat.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <time.h>
#include <math.h>
#include "sem.h"
#include "keys.h"

int main(int argc, char* argv[]){
  int buff_id, sem_full_id, sem_free_id, sem_data;
  int sem_readers_id, sem_readA_id, sem_readB_id, mutex_readers;
  int seg_size;
  char *buff;
  int loop;
  char letter;
  seg_size=(1+MAX_BUFF)*sizeof(char);

  buff_id=shmget(buff_key, seg_size, 0666| IPC_CREAT);

  if(buff_id<0){
	printf("shmget error");
	exit(1);
  }
  buff=(char*)shmat(buff_id, 0, 0);

  if( (sem_readA_id = sem_allocate(sem_readA_key , 0666 | IPC_CREAT)) < 0) exit(1);
  if( (mutex_readers = mutex_allocate(mutex_readers_key, 0666 | IPC_CREAT)) < 0) exit(1);

  if( (sem_readB_id = sem_allocate(sem_readB_key , 0666 | IPC_CREAT)) < 0) exit(1);

  if( (sem_readers_id = sem_allocate(sem_readers_key , 0666 | IPC_CREAT)) < 0) exit(1);

  if( (buff_id = mutex_allocate(sem_buff_key, 0666 | IPC_CREAT)) < 0) exit(1);

  if( (sem_data = sem_allocate(sem_data_key, 0666 | IPC_CREAT)) < 0) exit(1);

  if( (sem_free_id = sem_allocate(free_key, 0666 | IPC_CREAT)) < 0) exit(1);

  if( (sem_full_id = sem_allocate(full_key, 0666 | IPC_CREAT)) < 0) exit(1);

  mutex_init(buff_id);
  mutex_init(mutex_readers);
  sem_init(sem_readA_id, 1);
  sem_init(sem_readB_id, 1);
  sem_init(sem_readers_id, 0);
  sem_init(sem_data, 1);
  sem_init(sem_free_id, MAX_BUFF);
  sem_init(sem_full_id, 0);


  for(;;){
	if(sem_getVal(sem_data)<=0){
		break;
	}
                  //jest wiadomosc ?
              	    //czekaj az z queue mozna bedzie czytac
			mutex_wait(sem_full_id);
			printf("readerA dead");
			mutex_wait(sem_readA_id);
	      		mutex_wait(buff_id);
              		letter = bufferGet(buff);       //pobierz wiadomosc ale nie zdejmu
			printf("read: %d \n", letter);
			sem_change(sem_readA_id, -1);
        		sem_change(sem_readers_id, 1);
			mutex_post(buff_id);

               	     //wyjdz z sekcji krytycznej
  	       	randSleep2();


}
                 // powiedz innym aby break;
  union semun arg;
  arg.val = 0;
  semctl(sem_data, 0, SETVAL, arg);

  // wyłączamy segment pamięci wspólnej
  shmdt(buff);

   mutex_deallocate(buff_id);
   mutex_deallocate(sem_readA_id);
   mutex_deallocate(sem_readers_id);
   mutex_deallocate(mutex_readers);
   sem_deallocate(sem_free_id);
   sem_deallocate(sem_full_id);
   sem_deallocate(sem_data);


  return 0;
}