int pBlocked=0, cBlocked=0, pass;
sem_t pWait=0, cWait=0;
sem_t m=1, m2=1;


void bProduce(int value){
  int localCBlocked, c;

  P(m);
  if(cBlocked==0){
    pBlocked++;
    V(m);
    P(cWait);
  }
  localCBlocked = cBlocked;
  pass = value;

  for(c=0; c<localCBlocked; c++) V(pWait);
}


int bConsume() {
  int ret;

  P(m);
  cBlocked++;
  if(pBlocked){
    pBlocked--;
    V(cWait);
  }else{
    V(m);
  }
 P(pWait);

  P(m2);
  cBlocked--;
  ret = pass;
  if(cBlocked==0) V(m);
  V(m2);
}