相当于FIFO释放顺序的RAII

Question

RAII非常舒适，我很难为必须以获取资源的相同顺序（FIFO）释放资源而不是从RAII中自然产生的相反顺序（堆栈）释放资源提供等效设计。] >

在我的特定情况下，我有一个stream类，如下所示：

template<typename T>
class stream {
  ...
public:
  // Producer API
  T& write_acquire(); // This acquires a storage element and will "block"
                      // until a slot is available in the underlying resource
  void write_release(&T); // This releases the storage element, transferring the data to a consumer

  // Consumer API
  T& read_acquire(); // This acquires a storage element and will "block"
                     // until a slot has been write_release
  void read_release(&T); // This releases the storage element making it available
                         // for a potential future write_acquire
};
[我当时正在考虑提供RAII风格的助手：

template<typename T>
class stream_wslot {
  stream<T> &s;
  T &slot;
public:
  stream_wslot(stream<T> &s) : s{s}, slot{s.write_acquire()} {}
  ~stream_wslot() { s.write_release(slot); }

  operator T&() { return slot; }
  T& operator=(T &val) { return slot = val; }
};
但是问题在于以下用法将无法正确执行：

void test(stream<float> &fifo) {
  stream_wslot even(fifo);
  stream_wslot odd(fifo);
  ... first ...
  ... second ...
  // releases odd !!!
  // releases even
}
即，在释放odd插槽之前，我们将释放even插槽。虽然我可以在stream中添加“重新排序”队列，但我想知道是否存在将RAII推广到那些情况的“干净”方法。

RAII非常舒适，我很难为必须以与获取时相同的顺序释放它们的资源（FIFO）进行释放提供等效设计，而不是相反...

Answer 1