Add new /dev/poll reactor implementation for Solaris.

This commit is contained in:
chris_kohlhoff 2007-10-10 22:56:39 +00:00
parent bd8606ed10
commit a97c0b7590
7 changed files with 693 additions and 0 deletions

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@ -64,6 +64,9 @@ private:
#elif defined(ASIO_HAS_KQUEUE)
typedef detail::reactive_socket_service<
Protocol, detail::kqueue_reactor<false> > service_impl_type;
#elif defined(ASIO_HAS_DEV_POLL)
typedef detail::reactive_socket_service<
Protocol, detail::dev_poll_reactor<false> > service_impl_type;
#else
typedef detail::reactive_socket_service<
Protocol, detail::select_reactor<false> > service_impl_type;

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@ -69,6 +69,9 @@ private:
#elif defined(ASIO_HAS_KQUEUE)
typedef detail::deadline_timer_service<
traits_type, detail::kqueue_reactor<false> > service_impl_type;
#elif defined(ASIO_HAS_DEV_POLL)
typedef detail::deadline_timer_service<
traits_type, detail::dev_poll_reactor<false> > service_impl_type;
#else
typedef detail::deadline_timer_service<
traits_type, detail::select_reactor<false> > service_impl_type;

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@ -0,0 +1,638 @@
//
// dev_poll_reactor.hpp
// ~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2007 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_DEV_POLL_REACTOR_HPP
#define ASIO_DETAIL_DEV_POLL_REACTOR_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include "asio/detail/push_options.hpp"
#include "asio/detail/dev_poll_reactor_fwd.hpp"
#if defined(ASIO_HAS_DEV_POLL)
#include "asio/detail/push_options.hpp"
#include <cstddef>
#include <vector>
#include <boost/config.hpp>
#include <boost/date_time/posix_time/posix_time_types.hpp>
#include <boost/throw_exception.hpp>
#include <sys/devpoll.h>
#include "asio/detail/pop_options.hpp"
#include "asio/error.hpp"
#include "asio/io_service.hpp"
#include "asio/system_error.hpp"
#include "asio/detail/bind_handler.hpp"
#include "asio/detail/hash_map.hpp"
#include "asio/detail/mutex.hpp"
#include "asio/detail/task_io_service.hpp"
#include "asio/detail/thread.hpp"
#include "asio/detail/reactor_op_queue.hpp"
#include "asio/detail/select_interrupter.hpp"
#include "asio/detail/service_base.hpp"
#include "asio/detail/signal_blocker.hpp"
#include "asio/detail/socket_types.hpp"
#include "asio/detail/timer_queue.hpp"
namespace asio {
namespace detail {
template <bool Own_Thread>
class dev_poll_reactor
: public asio::detail::service_base<dev_poll_reactor<Own_Thread> >
{
public:
// Constructor.
dev_poll_reactor(asio::io_service& io_service)
: asio::detail::service_base<dev_poll_reactor<Own_Thread> >(io_service),
mutex_(),
dev_poll_fd_(do_dev_poll_create()),
wait_in_progress_(false),
interrupter_(),
read_op_queue_(),
write_op_queue_(),
except_op_queue_(),
pending_cancellations_(),
stop_thread_(false),
thread_(0),
shutdown_(false)
{
// Start the reactor's internal thread only if needed.
if (Own_Thread)
{
asio::detail::signal_blocker sb;
thread_ = new asio::detail::thread(
bind_handler(&dev_poll_reactor::call_run_thread, this));
}
// Add the interrupter's descriptor to /dev/poll.
::pollfd ev = { 0 };
ev.fd = interrupter_.read_descriptor();
ev.events = POLLIN | POLLERR;
ev.revents = 0;
::write(dev_poll_fd_, &ev, sizeof(ev));
}
// Destructor.
~dev_poll_reactor()
{
shutdown_service();
::close(dev_poll_fd_);
}
// Destroy all user-defined handler objects owned by the service.
void shutdown_service()
{
asio::detail::mutex::scoped_lock lock(mutex_);
shutdown_ = true;
stop_thread_ = true;
lock.unlock();
if (thread_)
{
interrupter_.interrupt();
thread_->join();
delete thread_;
thread_ = 0;
}
read_op_queue_.destroy_operations();
write_op_queue_.destroy_operations();
except_op_queue_.destroy_operations();
for (std::size_t i = 0; i < timer_queues_.size(); ++i)
timer_queues_[i]->destroy_timers();
timer_queues_.clear();
}
// Register a socket with the reactor. Returns 0 on success, system error
// code on failure.
int register_descriptor(socket_type descriptor)
{
return 0;
}
// Start a new read operation. The handler object will be invoked when the
// given descriptor is ready to be read, or an error has occurred.
template <typename Handler>
void start_read_op(socket_type descriptor, Handler handler)
{
asio::detail::mutex::scoped_lock lock(mutex_);
if (shutdown_)
return;
if (!read_op_queue_.has_operation(descriptor))
if (handler(asio::error_code()))
return;
if (read_op_queue_.enqueue_operation(descriptor, handler))
{
::pollfd ev = { 0 };
ev.fd = descriptor;
ev.events = POLLIN | POLLERR | POLLHUP;
if (write_op_queue_.has_operation(descriptor))
ev.events |= POLLOUT;
if (except_op_queue_.has_operation(descriptor))
ev.events |= POLLPRI;
ev.revents = 0;
int result = ::write(dev_poll_fd_, &ev, sizeof(ev));
if (result != sizeof(ev))
{
asio::error_code ec(errno,
asio::error::system_category);
read_op_queue_.dispatch_all_operations(descriptor, ec);
}
}
}
// Start a new write operation. The handler object will be invoked when the
// given descriptor is ready to be written, or an error has occurred.
template <typename Handler>
void start_write_op(socket_type descriptor, Handler handler)
{
asio::detail::mutex::scoped_lock lock(mutex_);
if (shutdown_)
return;
if (!write_op_queue_.has_operation(descriptor))
if (handler(asio::error_code()))
return;
if (write_op_queue_.enqueue_operation(descriptor, handler))
{
::pollfd ev = { 0 };
ev.fd = descriptor;
ev.events = POLLOUT | POLLERR | POLLHUP;
if (read_op_queue_.has_operation(descriptor))
ev.events |= POLLIN;
if (except_op_queue_.has_operation(descriptor))
ev.events |= POLLPRI;
ev.revents = 0;
int result = ::write(dev_poll_fd_, &ev, sizeof(ev));
if (result != sizeof(ev))
{
asio::error_code ec(errno,
asio::error::system_category);
write_op_queue_.dispatch_all_operations(descriptor, ec);
}
}
}
// Start a new exception operation. The handler object will be invoked when
// the given descriptor has exception information, or an error has occurred.
template <typename Handler>
void start_except_op(socket_type descriptor, Handler handler)
{
asio::detail::mutex::scoped_lock lock(mutex_);
if (shutdown_)
return;
if (except_op_queue_.enqueue_operation(descriptor, handler))
{
::pollfd ev = { 0 };
ev.fd = descriptor;
ev.events = POLLPRI | POLLERR | POLLHUP;
if (read_op_queue_.has_operation(descriptor))
ev.events |= POLLIN;
if (write_op_queue_.has_operation(descriptor))
ev.events |= POLLOUT;
ev.revents = 0;
int result = ::write(dev_poll_fd_, &ev, sizeof(ev));
if (result != sizeof(ev))
{
asio::error_code ec(errno,
asio::error::system_category);
except_op_queue_.dispatch_all_operations(descriptor, ec);
}
}
}
// Start new write and exception operations. The handler object will be
// invoked when the given descriptor is ready for writing or has exception
// information available, or an error has occurred.
template <typename Handler>
void start_write_and_except_ops(socket_type descriptor, Handler handler)
{
asio::detail::mutex::scoped_lock lock(mutex_);
if (shutdown_)
return;
bool need_mod = write_op_queue_.enqueue_operation(descriptor, handler);
need_mod = except_op_queue_.enqueue_operation(descriptor, handler)
&& need_mod;
if (need_mod)
{
::pollfd ev = { 0 };
ev.fd = descriptor;
ev.events = POLLOUT | POLLPRI | POLLERR | POLLHUP;
if (read_op_queue_.has_operation(descriptor))
ev.events |= POLLIN;
ev.revents = 0;
int result = ::write(dev_poll_fd_, &ev, sizeof(ev));
if (result != sizeof(ev))
{
asio::error_code ec(errno,
asio::error::system_category);
write_op_queue_.dispatch_all_operations(descriptor, ec);
except_op_queue_.dispatch_all_operations(descriptor, ec);
}
}
}
// Cancel all operations associated with the given descriptor. The
// handlers associated with the descriptor will be invoked with the
// operation_aborted error.
void cancel_ops(socket_type descriptor)
{
asio::detail::mutex::scoped_lock lock(mutex_);
cancel_ops_unlocked(descriptor);
}
// Enqueue cancellation of all operations associated with the given
// descriptor. The handlers associated with the descriptor will be invoked
// with the operation_aborted error. This function does not acquire the
// dev_poll_reactor's mutex, and so should only be used from within a reactor
// handler.
void enqueue_cancel_ops_unlocked(socket_type descriptor)
{
pending_cancellations_.push_back(descriptor);
}
// Cancel any operations that are running against the descriptor and remove
// its registration from the reactor.
void close_descriptor(socket_type descriptor)
{
asio::detail::mutex::scoped_lock lock(mutex_);
// Remove the descriptor from /dev/poll.
::pollfd ev = { 0 };
ev.fd = descriptor;
ev.events = POLLREMOVE;
ev.revents = 0;
::write(dev_poll_fd_, &ev, sizeof(ev));
// Cancel any outstanding operations associated with the descriptor.
cancel_ops_unlocked(descriptor);
}
// Add a new timer queue to the reactor.
template <typename Time_Traits>
void add_timer_queue(timer_queue<Time_Traits>& timer_queue)
{
asio::detail::mutex::scoped_lock lock(mutex_);
timer_queues_.push_back(&timer_queue);
}
// Remove a timer queue from the reactor.
template <typename Time_Traits>
void remove_timer_queue(timer_queue<Time_Traits>& timer_queue)
{
asio::detail::mutex::scoped_lock lock(mutex_);
for (std::size_t i = 0; i < timer_queues_.size(); ++i)
{
if (timer_queues_[i] == &timer_queue)
{
timer_queues_.erase(timer_queues_.begin() + i);
return;
}
}
}
// Schedule a timer in the given timer queue to expire at the specified
// absolute time. The handler object will be invoked when the timer expires.
template <typename Time_Traits, typename Handler>
void schedule_timer(timer_queue<Time_Traits>& timer_queue,
const typename Time_Traits::time_type& time, Handler handler, void* token)
{
asio::detail::mutex::scoped_lock lock(mutex_);
if (!shutdown_)
if (timer_queue.enqueue_timer(time, handler, token))
interrupter_.interrupt();
}
// Cancel the timer associated with the given token. Returns the number of
// handlers that have been posted or dispatched.
template <typename Time_Traits>
std::size_t cancel_timer(timer_queue<Time_Traits>& timer_queue, void* token)
{
asio::detail::mutex::scoped_lock lock(mutex_);
std::size_t n = timer_queue.cancel_timer(token);
if (n > 0)
interrupter_.interrupt();
return n;
}
private:
friend class task_io_service<dev_poll_reactor<Own_Thread> >;
// Run /dev/poll once until interrupted or events are ready to be dispatched.
void run(bool block)
{
asio::detail::mutex::scoped_lock lock(mutex_);
// Dispatch any operation cancellations that were made while the select
// loop was not running.
read_op_queue_.dispatch_cancellations();
write_op_queue_.dispatch_cancellations();
except_op_queue_.dispatch_cancellations();
for (std::size_t i = 0; i < timer_queues_.size(); ++i)
timer_queues_[i]->dispatch_cancellations();
// Check if the thread is supposed to stop.
if (stop_thread_)
{
cleanup_operations_and_timers(lock);
return;
}
// We can return immediately if there's no work to do and the reactor is
// not supposed to block.
if (!block && read_op_queue_.empty() && write_op_queue_.empty()
&& except_op_queue_.empty() && all_timer_queues_are_empty())
{
cleanup_operations_and_timers(lock);
return;
}
int timeout = block ? get_timeout() : 0;
wait_in_progress_ = true;
lock.unlock();
// Block on the /dev/poll descriptor.
::pollfd events[128] = { { 0 } };
::dvpoll dp = { 0 };
dp.dp_fds = events;
dp.dp_nfds = 128;
dp.dp_timeout = timeout;
int num_events = ::ioctl(dev_poll_fd_, DP_POLL, &dp);
lock.lock();
wait_in_progress_ = false;
// Block signals while dispatching operations.
asio::detail::signal_blocker sb;
// Dispatch the waiting events.
for (int i = 0; i < num_events; ++i)
{
int descriptor = events[i].fd;
if (descriptor == interrupter_.read_descriptor())
{
interrupter_.reset();
}
else
{
bool more_reads = false;
bool more_writes = false;
bool more_except = false;
asio::error_code ec;
// Exception operations must be processed first to ensure that any
// out-of-band data is read before normal data.
if (events[i].events & (POLLPRI | POLLERR | POLLHUP))
more_except = except_op_queue_.dispatch_operation(descriptor, ec);
else
more_except = except_op_queue_.has_operation(descriptor);
if (events[i].events & (POLLIN | POLLERR | POLLHUP))
more_reads = read_op_queue_.dispatch_operation(descriptor, ec);
else
more_reads = read_op_queue_.has_operation(descriptor);
if (events[i].events & (POLLOUT | POLLERR | POLLHUP))
more_writes = write_op_queue_.dispatch_operation(descriptor, ec);
else
more_writes = write_op_queue_.has_operation(descriptor);
if ((events[i].events == POLLHUP)
&& !more_except && !more_reads && !more_writes)
{
// If we have only an POLLHUP event and no operations associated
// with the descriptor then we need to delete the descriptor from
// /dev/poll. The poll operation might produce POLLHUP events even
// if they are not specifically requested, so if we do not remove the
// descriptor we can end up in a tight polling loop.
::pollfd ev = { 0 };
ev.fd = descriptor;
ev.events = POLLREMOVE;
ev.revents = 0;
::write(dev_poll_fd_, &ev, sizeof(ev));
}
else
{
::pollfd ev = { 0 };
ev.fd = descriptor;
ev.events = POLLERR | POLLHUP;
if (more_reads)
ev.events |= POLLIN;
if (more_writes)
ev.events |= POLLOUT;
if (more_except)
ev.events |= POLLPRI;
ev.revents = 0;
int result = ::write(dev_poll_fd_, &ev, sizeof(ev));
if (result != sizeof(ev))
{
ec = asio::error_code(errno,
asio::error::system_category);
read_op_queue_.dispatch_all_operations(descriptor, ec);
write_op_queue_.dispatch_all_operations(descriptor, ec);
except_op_queue_.dispatch_all_operations(descriptor, ec);
}
}
}
}
read_op_queue_.dispatch_cancellations();
write_op_queue_.dispatch_cancellations();
except_op_queue_.dispatch_cancellations();
for (std::size_t i = 0; i < timer_queues_.size(); ++i)
{
timer_queues_[i]->dispatch_timers();
timer_queues_[i]->dispatch_cancellations();
}
// Issue any pending cancellations.
for (size_t i = 0; i < pending_cancellations_.size(); ++i)
cancel_ops_unlocked(pending_cancellations_[i]);
pending_cancellations_.clear();
cleanup_operations_and_timers(lock);
}
// Run the select loop in the thread.
void run_thread()
{
asio::detail::mutex::scoped_lock lock(mutex_);
while (!stop_thread_)
{
lock.unlock();
run(true);
lock.lock();
}
}
// Entry point for the select loop thread.
static void call_run_thread(dev_poll_reactor* reactor)
{
reactor->run_thread();
}
// Interrupt the select loop.
void interrupt()
{
interrupter_.interrupt();
}
// Create the /dev/poll file descriptor. Throws an exception if the descriptor
// cannot be created.
static int do_dev_poll_create()
{
int fd = ::open("/dev/poll", O_RDWR);
if (fd == -1)
{
boost::throw_exception(
asio::system_error(
asio::error_code(errno,
asio::error::system_category),
"/dev/poll"));
}
return fd;
}
// Check if all timer queues are empty.
bool all_timer_queues_are_empty() const
{
for (std::size_t i = 0; i < timer_queues_.size(); ++i)
if (!timer_queues_[i]->empty())
return false;
return true;
}
// Get the timeout value for the /dev/poll DP_POLL operation. The timeout
// value is returned as a number of milliseconds. A return value of -1
// indicates that the poll should block indefinitely.
int get_timeout()
{
if (all_timer_queues_are_empty())
return -1;
// By default we will wait no longer than 5 minutes. This will ensure that
// any changes to the system clock are detected after no longer than this.
boost::posix_time::time_duration minimum_wait_duration
= boost::posix_time::minutes(5);
for (std::size_t i = 0; i < timer_queues_.size(); ++i)
{
boost::posix_time::time_duration wait_duration
= timer_queues_[i]->wait_duration();
if (wait_duration < minimum_wait_duration)
minimum_wait_duration = wait_duration;
}
if (minimum_wait_duration > boost::posix_time::time_duration())
{
int milliseconds = minimum_wait_duration.total_milliseconds();
return milliseconds > 0 ? milliseconds : 1;
}
else
{
return 0;
}
}
// Cancel all operations associated with the given descriptor. The do_cancel
// function of the handler objects will be invoked. This function does not
// acquire the dev_poll_reactor's mutex.
void cancel_ops_unlocked(socket_type descriptor)
{
bool interrupt = read_op_queue_.cancel_operations(descriptor);
interrupt = write_op_queue_.cancel_operations(descriptor) || interrupt;
interrupt = except_op_queue_.cancel_operations(descriptor) || interrupt;
if (interrupt)
interrupter_.interrupt();
}
// Clean up operations and timers. We must not hold the lock since the
// destructors may make calls back into this reactor. We make a copy of the
// vector of timer queues since the original may be modified while the lock
// is not held.
void cleanup_operations_and_timers(
asio::detail::mutex::scoped_lock& lock)
{
timer_queues_for_cleanup_ = timer_queues_;
lock.unlock();
read_op_queue_.cleanup_operations();
write_op_queue_.cleanup_operations();
except_op_queue_.cleanup_operations();
for (std::size_t i = 0; i < timer_queues_for_cleanup_.size(); ++i)
timer_queues_for_cleanup_[i]->cleanup_timers();
}
// Mutex to protect access to internal data.
asio::detail::mutex mutex_;
// The /dev/poll file descriptor.
int dev_poll_fd_;
// Whether the DP_POLL operation is currently in progress
bool wait_in_progress_;
// The interrupter is used to break a blocking DP_POLL operation.
select_interrupter interrupter_;
// The queue of read operations.
reactor_op_queue<socket_type> read_op_queue_;
// The queue of write operations.
reactor_op_queue<socket_type> write_op_queue_;
// The queue of except operations.
reactor_op_queue<socket_type> except_op_queue_;
// The timer queues.
std::vector<timer_queue_base*> timer_queues_;
// A copy of the timer queues, used when cleaning up timers. The copy is
// stored as a class data member to avoid unnecessary memory allocation.
std::vector<timer_queue_base*> timer_queues_for_cleanup_;
// The descriptors that are pending cancellation.
std::vector<socket_type> pending_cancellations_;
// Does the reactor loop thread need to stop.
bool stop_thread_;
// The thread that is running the reactor loop.
asio::detail::thread* thread_;
// Whether the service has been shut down.
bool shutdown_;
};
} // namespace detail
} // namespace asio
#endif // defined(ASIO_HAS_DEV_POLL)
#include "asio/detail/pop_options.hpp"
#endif // ASIO_DETAIL_DEV_POLL_REACTOR_HPP

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@ -0,0 +1,40 @@
//
// dev_poll_reactor_fwd.hpp
// ~~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2007 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_DEV_POLL_REACTOR_FWD_HPP
#define ASIO_DETAIL_DEV_POLL_REACTOR_FWD_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include "asio/detail/push_options.hpp"
#if !defined(ASIO_DISABLE_DEV_POLL)
#if defined(__sun) // This service is only supported on Solaris.
// Define this to indicate that /dev/poll is supported on the target platform.
#define ASIO_HAS_DEV_POLL 1
namespace asio {
namespace detail {
template <bool Own_Thread>
class dev_poll_reactor;
} // namespace detail
} // namespace asio
#endif // defined(__sun)
#endif // !defined(ASIO_DISABLE_DEV_POLL)
#include "asio/detail/pop_options.hpp"
#endif // ASIO_DETAIL_DEV_POLL_REACTOR_FWD_HPP

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@ -26,6 +26,7 @@
#include "asio/detail/pop_options.hpp"
#include "asio/error_code.hpp"
#include "asio/detail/dev_poll_reactor_fwd.hpp"
#include "asio/detail/epoll_reactor_fwd.hpp"
#include "asio/detail/kqueue_reactor_fwd.hpp"
#include "asio/detail/noncopyable.hpp"
@ -111,6 +112,8 @@ private:
typedef detail::task_io_service<detail::epoll_reactor<false> > impl_type;
#elif defined(ASIO_HAS_KQUEUE)
typedef detail::task_io_service<detail::kqueue_reactor<false> > impl_type;
#elif defined(ASIO_HAS_DEV_POLL)
typedef detail::task_io_service<detail::dev_poll_reactor<false> > impl_type;
#else
typedef detail::task_io_service<detail::select_reactor<false> > impl_type;
#endif

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@ -60,6 +60,9 @@ private:
#elif defined(ASIO_HAS_KQUEUE)
typedef detail::reactive_socket_service<
Protocol, detail::kqueue_reactor<false> > service_impl_type;
#elif defined(ASIO_HAS_DEV_POLL)
typedef detail::reactive_socket_service<
Protocol, detail::dev_poll_reactor<false> > service_impl_type;
#else
typedef detail::reactive_socket_service<
Protocol, detail::select_reactor<false> > service_impl_type;

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@ -64,6 +64,9 @@ private:
#elif defined(ASIO_HAS_KQUEUE)
typedef detail::reactive_socket_service<
Protocol, detail::kqueue_reactor<false> > service_impl_type;
#elif defined(ASIO_HAS_DEV_POLL)
typedef detail::reactive_socket_service<
Protocol, detail::dev_poll_reactor<false> > service_impl_type;
#else
typedef detail::reactive_socket_service<
Protocol, detail::select_reactor<false> > service_impl_type;