| 25 | |
| 26 | template<typename T> |
| 27 | class ThreadSafeQueue { |
| 28 | public: |
| 29 | void push(T item) { |
| 30 | { |
| 31 | std::lock_guard<std::mutex> lock(lock_); |
| 32 | queue_.push(std::move(item)); |
| 33 | } |
| 34 | cond_.notify_one(); |
| 35 | } |
| 36 | |
| 37 | T pop() { |
| 38 | std::unique_lock<std::mutex> lock{lock_}; |
| 39 | cond_.wait(lock, [&](){return !queue_.empty() || interrupt_;}); |
| 40 | if (interrupt_) { |
| 41 | return {}; |
| 42 | } |
| 43 | T item = std::move(queue_.front()); |
| 44 | queue_.pop(); |
| 45 | return item; |
| 46 | } |
| 47 | |
| 48 | const T& peek() { |
| 49 | return front(); |
| 50 | } |
| 51 | |
| 52 | T& front() { |
| 53 | static auto int_return = T{}; |
| 54 | std::unique_lock<std::mutex> lock{lock_}; |
| 55 | cond_.wait(lock, [&](){return !queue_.empty() || interrupt_;}); |
| 56 | if (interrupt_) { |
| 57 | return int_return; |
| 58 | } |
| 59 | return queue_.front(); |
| 60 | } |
| 61 | |
| 62 | bool empty() const { |
| 63 | return queue_.empty(); |
| 64 | } |
| 65 | |
| 66 | typename std::queue<T>::size_type size() const { |
| 67 | return queue_.size(); |
| 68 | } |
| 69 | |
| 70 | void shutdown() { |
| 71 | interrupt_ = true; |
| 72 | cond_.notify_all(); |
| 73 | } |
| 74 | |
| 75 | private: |
| 76 | std::queue<T> queue_; |
| 77 | std::mutex lock_; |
| 78 | std::condition_variable cond_; |
| 79 | bool interrupt_ = false; |
| 80 | }; |
| 81 | |
| 82 | } // namespace dali |
| 83 | |