#include <stdlib.h>
#include <stdio.h>
#include <pthread.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>

#define CANS 2
#define CLIENTS 6

void * func (void * arg_wsk);
struct pub {int cansTab[CANS]; pthread_mutex_t* mutex; pthread_mutex_t* mutex2;};
static int threadNumber= 0;

int main(){
  pthread_mutex_t mutex, mutex2;

  struct pub pub1;
  pub1.mutex = &mutex;
  pub1.mutex2 = &mutex2;
  int i;
  for(i=0; i<CANS; i++)
      pub1.cansTab[i] = 1;

  pthread_t tid[CLIENTS];

  for(i=0; i < CLIENTS; i++)
  {
   pthread_create(&tid[i], NULL, func, &pub1);
  }

  for(i=0; i < CLIENTS; i++)
  {
   pthread_join(tid[i],NULL);

  }
}

void * func (void * arg_wsk){
  struct pub *pub_wsk = arg_wsk;

  int thread_nr = threadNumber++;

  int i, canNr, useCanNr;
  for(i=0;i<2;i++)
  {
	  printf("Klient %d: chcialby wypic %d piwo \n", thread_nr, 1+i);

	  while(1)
	  {
		{
			if(pthread_mutex_trylock(&pub_wsk->mutex[canNr%CANS])==0)
			{
				useCanNr = canNr%CANS;
				break;
			}
			else { canNr++; }
		}
	  pthread_mutex_lock(pub_wsk->mutex2);
	  usleep(500);
	  pthread_mutex_unlock(pub_wsk->mutex2);
	  printf("Klient %d: ma kufel. Pije %d piwo z %d kufla \n", thread_nr, i+1, useCanNr+1);
	  usleep(2500);
	  printf("Klient %d: wypił %d piwo. Odklada %d kufel \n", thread_nr, i+1, useCanNr+1);
	  pthread_mutex_unlock (&pub_wsk->mutex[useCanNr]);
  }
  return(NULL);
}