vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/asio/detail/posix_event.hpp

129 lines
2.9 KiB
C++

//
// detail/posix_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 BOOST_ASIO_DETAIL_POSIX_EVENT_HPP
#define BOOST_ASIO_DETAIL_POSIX_EVENT_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include <boost/asio/detail/config.hpp>
#if defined(BOOST_ASIO_HAS_PTHREADS)
#include <pthread.h>
#include <boost/asio/detail/assert.hpp>
#include <boost/asio/detail/noncopyable.hpp>
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
namespace detail {
class posix_event
: private noncopyable
{
public:
// Constructor.
BOOST_ASIO_DECL posix_event();
// Destructor.
~posix_event()
{
::pthread_cond_destroy(&cond_);
}
// 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)
{
BOOST_ASIO_ASSERT(lock.locked());
(void)lock;
state_ |= 1;
::pthread_cond_broadcast(&cond_); // Ignore EINVAL.
}
// Unlock the mutex and signal one waiter.
template <typename Lock>
void unlock_and_signal_one(Lock& lock)
{
BOOST_ASIO_ASSERT(lock.locked());
state_ |= 1;
bool have_waiters = (state_ > 1);
lock.unlock();
if (have_waiters)
::pthread_cond_signal(&cond_); // Ignore EINVAL.
}
// If there's a waiter, unlock the mutex and signal it.
template <typename Lock>
bool maybe_unlock_and_signal_one(Lock& lock)
{
BOOST_ASIO_ASSERT(lock.locked());
state_ |= 1;
if (state_ > 1)
{
lock.unlock();
::pthread_cond_signal(&cond_); // Ignore EINVAL.
return true;
}
return false;
}
// Reset the event.
template <typename Lock>
void clear(Lock& lock)
{
BOOST_ASIO_ASSERT(lock.locked());
(void)lock;
state_ &= ~std::size_t(1);
}
// Wait for the event to become signalled.
template <typename Lock>
void wait(Lock& lock)
{
BOOST_ASIO_ASSERT(lock.locked());
while ((state_ & 1) == 0)
{
state_ += 2;
::pthread_cond_wait(&cond_, &lock.mutex().mutex_); // Ignore EINVAL.
state_ -= 2;
}
}
private:
::pthread_cond_t cond_;
std::size_t state_;
};
} // namespace detail
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#if defined(BOOST_ASIO_HEADER_ONLY)
# include <boost/asio/detail/impl/posix_event.ipp>
#endif // defined(BOOST_ASIO_HEADER_ONLY)
#endif // defined(BOOST_ASIO_HAS_PTHREADS)
#endif // BOOST_ASIO_DETAIL_POSIX_EVENT_HPP