Atomic.h

#ifndef MUDUO_BASE_ATOMIC_H
#define MUDUO_BASE_ATOMIC_H

#include <stdint.h>

template<typename T>
class Atomic
{
 public:
  Atomic<T>():value_(0){}
  T get()
  {
    // in gcc >= 4.7: __atomic_load_n(&value_, __ATOMIC_SEQ_CST)
    return __sync_val_compare_and_swap(&value_, 0, 0);
  }

  T getAndAdd(T x)
  {
    // in gcc >= 4.7: __atomic_fetch_add(&value_, x, __ATOMIC_SEQ_CST)
    return __sync_fetch_and_add(&value_, x);
  }

  T addAndGet(T x)
  {
    return getAndAdd(x) + x;
  }

  T incrementAndGet()
  {
    return addAndGet(1);
  }

  T decrementAndGet()
  {
    return addAndGet(-1);
  }

  void add(T x)
  {
    getAndAdd(x);
  }

  void increment()
  {
    incrementAndGet();
  }

  void decrement()
  {
    decrementAndGet();
  }

  T getAndSet(T newValue)
  {
    // in gcc >= 4.7: __atomic_exchange_n(&value, newValue, __ATOMIC_SEQ_CST)
    return __sync_lock_test_and_set(&value_, newValue);
  }





 private:
  volatile T value_;

};

typedef Atomic<int32_t> AtomicInt32;
typedef Atomic<int64_t> AtomicInt64;

#endif