| // |
| // detail/win_event.hpp |
| // ~~~~~~~~~~~~~~~~~~~~ |
| // |
| // Copyright (c) 2003-2016 Christopher M. Kohlhoff (chris at kohlhoff dot com) |
| // |
| // Distributed under the Boost Software License, Version 1.0. (See accompanying |
| // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| // |
| |
| #ifndef ASIO_DETAIL_WIN_EVENT_HPP |
| #define ASIO_DETAIL_WIN_EVENT_HPP |
| |
| #if defined(_MSC_VER) && (_MSC_VER >= 1200) |
| # pragma once |
| #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) |
| |
| #include "asio/detail/config.hpp" |
| |
| #if defined(ASIO_WINDOWS) |
| |
| #include "asio/detail/assert.hpp" |
| #include "asio/detail/noncopyable.hpp" |
| #include "asio/detail/socket_types.hpp" |
| |
| #include "asio/detail/push_options.hpp" |
| |
| namespace asio { |
| namespace detail { |
| |
| class win_event |
| : private noncopyable |
| { |
| public: |
| // Constructor. |
| ASIO_DECL win_event(); |
| |
| // Destructor. |
| ASIO_DECL ~win_event(); |
| |
| // Signal the event. (Retained for backward compatibility.) |
| template <typename Lock> |
| void signal(Lock& lock) |
| { |
| this->signal_all(lock); |
| } |
| |
| // Signal all waiters. |
| template <typename Lock> |
| void signal_all(Lock& lock) |
| { |
| ASIO_ASSERT(lock.locked()); |
| (void)lock; |
| state_ |= 1; |
| ::SetEvent(events_[0]); |
| } |
| |
| // Unlock the mutex and signal one waiter. |
| template <typename Lock> |
| void unlock_and_signal_one(Lock& lock) |
| { |
| ASIO_ASSERT(lock.locked()); |
| state_ |= 1; |
| bool have_waiters = (state_ > 1); |
| lock.unlock(); |
| if (have_waiters) |
| ::SetEvent(events_[1]); |
| } |
| |
| // If there's a waiter, unlock the mutex and signal it. |
| template <typename Lock> |
| bool maybe_unlock_and_signal_one(Lock& lock) |
| { |
| ASIO_ASSERT(lock.locked()); |
| state_ |= 1; |
| if (state_ > 1) |
| { |
| lock.unlock(); |
| ::SetEvent(events_[1]); |
| return true; |
| } |
| return false; |
| } |
| |
| // Reset the event. |
| template <typename Lock> |
| void clear(Lock& lock) |
| { |
| ASIO_ASSERT(lock.locked()); |
| (void)lock; |
| ::ResetEvent(events_[0]); |
| state_ &= ~std::size_t(1); |
| } |
| |
| // Wait for the event to become signalled. |
| template <typename Lock> |
| void wait(Lock& lock) |
| { |
| ASIO_ASSERT(lock.locked()); |
| while ((state_ & 1) == 0) |
| { |
| state_ += 2; |
| lock.unlock(); |
| #if defined(ASIO_WINDOWS_APP) |
| ::WaitForMultipleObjectsEx(2, events_, false, INFINITE, false); |
| #else // defined(ASIO_WINDOWS_APP) |
| ::WaitForMultipleObjects(2, events_, false, INFINITE); |
| #endif // defined(ASIO_WINDOWS_APP) |
| lock.lock(); |
| state_ -= 2; |
| } |
| } |
| |
| // Timed wait for the event to become signalled. |
| template <typename Lock> |
| bool wait_for_usec(Lock& lock, long usec) |
| { |
| ASIO_ASSERT(lock.locked()); |
| if ((state_ & 1) == 0) |
| { |
| state_ += 2; |
| lock.unlock(); |
| DWORD msec = usec > 0 ? (usec < 1000 ? 1 : usec / 1000) : 0; |
| #if defined(ASIO_WINDOWS_APP) |
| ::WaitForMultipleObjectsEx(2, events_, false, msec, false); |
| #else // defined(ASIO_WINDOWS_APP) |
| ::WaitForMultipleObjects(2, events_, false, msec); |
| #endif // defined(ASIO_WINDOWS_APP) |
| lock.lock(); |
| state_ -= 2; |
| } |
| return (state_ & 1) != 0; |
| } |
| |
| private: |
| HANDLE events_[2]; |
| std::size_t state_; |
| }; |
| |
| } // namespace detail |
| } // namespace asio |
| |
| #include "asio/detail/pop_options.hpp" |
| |
| #if defined(ASIO_HEADER_ONLY) |
| # include "asio/detail/impl/win_event.ipp" |
| #endif // defined(ASIO_HEADER_ONLY) |
| |
| #endif // defined(ASIO_WINDOWS) |
| |
| #endif // ASIO_DETAIL_WIN_EVENT_HPP |