/*
 * Autor: Renan Adriani Sterle
 *
 * Verificar erro do incremento utilizando gbd.
 * (gdb) set non-stop off
 * (gdb) break 25
 * (gdb) break 39
 * (gdb) run
 * (gdb) info threads
 * (gdb) ...  (próximos comandos irão variar conforme a execução)
 */

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

volatile int Counter = 5;

void *IncrementB()
{
  int C = Counter;
	
  //Counter++ in assembly:
  asm("movl	Counter(%rip), %ebx\n");
  asm("addl	$1, %ebx\n");
  asm("movl	%ebx, Counter(%rip)\n");

  printf("IncrementB: %d + 1 = %d\n", C, Counter);

  return NULL;
}

void *IncrementA()
{
  int C = Counter;
	
  //Interrupted Counter++ in assembly:
  asm("movl	Counter(%rip), %ebx\n");
  asm("addl	$1, %ebx\n");
  asm("movl	%ebx, Counter(%rip)\n");
	
  printf("IncrementA: %d + 1 = %d\n", C, Counter);

  return NULL;
}

int main ()
{
  pthread_t ThreadA, ThreadB;
  pthread_create(&ThreadA, NULL, IncrementA, NULL);
  pthread_create(&ThreadB, NULL, IncrementB, NULL);
	
  pthread_join(ThreadA, NULL);
  pthread_join(ThreadB, NULL);
	
  printf("Final Counter: %d\n", Counter);

  return 0;
}