/*
 * Test program to consider what happens to local variables after the
 * function has completed.
 *
 * Brian D. Davison
 *
 * Last revised 5 Feb 2005
 */

#include <stdio.h>
#include <stdlib.h>

// Yes we are intentionally returning address of local variable
int *func1(void) {
   int a = 3;
   return &a;
}

// Yes we are intentionally returning address of local variable
int *func2(void) {
   int b = 4;
   return &b;
}

int *func3(void) {
  int *f1 = NULL;
  int *f2 = NULL;

  f1 = func1(); // record first result
  f2 = func2(); // record second result

  return f1; // send back first result
}

// This function doesn't actually do anything useful.
int usefloat(void) {
  float g=422.3;

  g *= 71;

  return (int) g/100;
}

int *func4(void) {
  int *f1 = NULL;
  int x;

  f1 = func1(); // record first result
  x = usefloat();  // some other kind of function

  return f1; // send back first result
}

int main(int argc, char *argv[]) {
  int choice = 0;
  int *result = NULL;

  if (argc != 2) {
    printf("Expects one argument: which function to run.\n");
    exit(-1);
  }

  choice = atoi(argv[1]);

  switch(choice) {
  case 1:
    printf("Expected result is 3.\n");
    result = func1();
    break;
  case 2:
    printf("Expected result is 4.\n");
    result = func2();
    break;
  case 3:
    printf("Expected result is 3.\n");
    result = func3();
    break;
  case 4:
    printf("Expected result is 3.\n");
    result = func4();
    break;
  default:
    printf("Invalid argument.\n");
    return (0);
  }

   printf("Actual result was %d\n", *result);

   return 0;
}