Insane_DNS/libraries/asio-1.28.1/include/asio/detail/win_event.hpp

165 lines
3.6 KiB
C++

//
// detail/win_event.hpp
// ~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2023 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 <cstddef>
#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]);
}
// Unlock the mutex and signal one waiter who may destroy us.
template <typename Lock>
void unlock_and_signal_one_for_destruction(Lock& lock)
{
ASIO_ASSERT(lock.locked());
state_ |= 1;
bool have_waiters = (state_ > 1);
if (have_waiters)
::SetEvent(events_[1]);
lock.unlock();
}
// 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