/*=========================================================*/
 /* race.c --- for playing with ECE437 */
 /*=========================================================*/
 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <pthread.h>
 struct {int balance[2];} Bank={{100,100}}; //global variable defined
 //Sem437* lock = (Sem437*)malloc(sizeof(Sem437));
 typedef struct {int S;} Sem437;

 void Sem437Init(Sem437* sem, int a)
 {
     printf("in init function\n");
     sem->S = 1;
     printf("leaving init function\n");
 }

 void Sem437P(Sem437* sem)
 {
     while(&sem->S == 0)
         ;
     sem->S--;
 }

 void Sem437V(Sem437* sem)
 {
     sem->S++;
 }
 // Sem437* lock;
  // Sem437Init(lock, 1);
   Sem437* lock = (Sem437*)malloc(sizeof(Sem437));
   //int a = 1;
   //lock->S = 1;

   void* MakeTransactions() { //routine for thread execution
   int i, j, tmp1, tmp2, rint; double dummy;

   Sem437P(lock);
   for (i=0; i < 100; i++) { rint = (rand()%30)-15;
   if (((tmp1=Bank.balance[0])+rint)>=0 && ((tmp2=Bank.balance[1])-rint)>=0) {
  // Sem437P(lock);
   Bank.balance[0] = tmp1 + rint;
  // Sem437V(lock);
   for (j=0; j < rint*100; j++) {dummy=2.345*8.765/1.234;}
  // Sem437P(lock);
   Bank.balance[1] = tmp2 - rint;
  // Sem437V(lock);
  }
  }
   Sem437V(lock);
   return NULL;
  }

  int main(int argc, char **argv) {
  int i; void* voidptr=NULL; pthread_t tid[2];
   //Sem437* lock;
   //Sem437* lock = (Sem437*)malloc(sizeof(Sem437));
   int a = 1;
   lock->S = 1;
   printf("got to here\n");
   //Sem437Init(lock, a);
   printf("Lock has value %d \n", lock->S);

   srand(getpid());
   printf("Init balances A:%d + B:%d ==> %d!\n",
   Bank.balance[0],Bank.balance[1],Bank.balance[0]+Bank.balance[1]);
   for (i=0; i<2; i++) if (pthread_create(&tid[i],NULL,MakeTransactions, NULL)) {
   fprintf(stderr, "Error in thread creating\n"); return(1); }
   for (i=0; i<2; i++) if (pthread_join(tid[i], (void*)&voidptr)) {
   fprintf(stderr, "Error in thread joining\n"); return(1);}
   printf("Let's check the balances A:%d + B:%d ==> %d ?= 200\n",
   Bank.balance[0],Bank.balance[1],Bank.balance[0]+Bank.balance[1]);
   return 0;
  }