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diff --git a/lib/asio/detail/impl/dev_poll_reactor.ipp b/lib/asio/detail/impl/dev_poll_reactor.ipp
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+++ b/lib/asio/detail/impl/dev_poll_reactor.ipp
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+//
+// detail/impl/dev_poll_reactor.ipp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2018 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_IMPL_DEV_POLL_REACTOR_IPP
+#define ASIO_DETAIL_IMPL_DEV_POLL_REACTOR_IPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include "asio/detail/config.hpp"
+
+#if defined(ASIO_HAS_DEV_POLL)
+
+#include "asio/detail/dev_poll_reactor.hpp"
+#include "asio/detail/assert.hpp"
+#include "asio/detail/throw_error.hpp"
+#include "asio/error.hpp"
+
+#include "asio/detail/push_options.hpp"
+
+namespace asio {
+namespace detail {
+
+dev_poll_reactor::dev_poll_reactor(asio::execution_context& ctx)
+  : asio::detail::execution_context_service_base<dev_poll_reactor>(ctx),
+    scheduler_(use_service<scheduler>(ctx)),
+    mutex_(),
+    dev_poll_fd_(do_dev_poll_create()),
+    interrupter_(),
+    shutdown_(false)
+{
+  // Add the interrupter's descriptor to /dev/poll.
+  ::pollfd ev = { 0, 0, 0 };
+  ev.fd = interrupter_.read_descriptor();
+  ev.events = POLLIN | POLLERR;
+  ev.revents = 0;
+  ::write(dev_poll_fd_, &ev, sizeof(ev));
+}
+
+dev_poll_reactor::~dev_poll_reactor()
+{
+  shutdown();
+  ::close(dev_poll_fd_);
+}
+
+void dev_poll_reactor::shutdown()
+{
+  asio::detail::mutex::scoped_lock lock(mutex_);
+  shutdown_ = true;
+  lock.unlock();
+
+  op_queue<operation> ops;
+
+  for (int i = 0; i < max_ops; ++i)
+    op_queue_[i].get_all_operations(ops);
+
+  timer_queues_.get_all_timers(ops);
+
+  scheduler_.abandon_operations(ops);
+} 
+
+void dev_poll_reactor::notify_fork(
+    asio::execution_context::fork_event fork_ev)
+{
+  if (fork_ev == asio::execution_context::fork_child)
+  {
+    detail::mutex::scoped_lock lock(mutex_);
+
+    if (dev_poll_fd_ != -1)
+      ::close(dev_poll_fd_);
+    dev_poll_fd_ = -1;
+    dev_poll_fd_ = do_dev_poll_create();
+
+    interrupter_.recreate();
+
+    // Add the interrupter's descriptor to /dev/poll.
+    ::pollfd ev = { 0, 0, 0 };
+    ev.fd = interrupter_.read_descriptor();
+    ev.events = POLLIN | POLLERR;
+    ev.revents = 0;
+    ::write(dev_poll_fd_, &ev, sizeof(ev));
+
+    // Re-register all descriptors with /dev/poll. The changes will be written
+    // to the /dev/poll descriptor the next time the reactor is run.
+    for (int i = 0; i < max_ops; ++i)
+    {
+      reactor_op_queue<socket_type>::iterator iter = op_queue_[i].begin();
+      reactor_op_queue<socket_type>::iterator end = op_queue_[i].end();
+      for (; iter != end; ++iter)
+      {
+        ::pollfd& pending_ev = add_pending_event_change(iter->first);
+        pending_ev.events |= POLLERR | POLLHUP;
+        switch (i)
+        {
+        case read_op: pending_ev.events |= POLLIN; break;
+        case write_op: pending_ev.events |= POLLOUT; break;
+        case except_op: pending_ev.events |= POLLPRI; break;
+        default: break;
+        }
+      }
+    }
+    interrupter_.interrupt();
+  }
+}
+
+void dev_poll_reactor::init_task()
+{
+  scheduler_.init_task();
+}
+
+int dev_poll_reactor::register_descriptor(socket_type, per_descriptor_data&)
+{
+  return 0;
+}
+
+int dev_poll_reactor::register_internal_descriptor(int op_type,
+    socket_type descriptor, per_descriptor_data&, reactor_op* op)
+{
+  asio::detail::mutex::scoped_lock lock(mutex_);
+
+  op_queue_[op_type].enqueue_operation(descriptor, op);
+  ::pollfd& ev = add_pending_event_change(descriptor);
+  ev.events = POLLERR | POLLHUP;
+  switch (op_type)
+  {
+  case read_op: ev.events |= POLLIN; break;
+  case write_op: ev.events |= POLLOUT; break;
+  case except_op: ev.events |= POLLPRI; break;
+  default: break;
+  }
+  interrupter_.interrupt();
+
+  return 0;
+}
+
+void dev_poll_reactor::move_descriptor(socket_type,
+    dev_poll_reactor::per_descriptor_data&,
+    dev_poll_reactor::per_descriptor_data&)
+{
+}
+
+void dev_poll_reactor::start_op(int op_type, socket_type descriptor,
+    dev_poll_reactor::per_descriptor_data&, reactor_op* op,
+    bool is_continuation, bool allow_speculative)
+{
+  asio::detail::mutex::scoped_lock lock(mutex_);
+
+  if (shutdown_)
+  {
+    post_immediate_completion(op, is_continuation);
+    return;
+  }
+
+  if (allow_speculative)
+  {
+    if (op_type != read_op || !op_queue_[except_op].has_operation(descriptor))
+    {
+      if (!op_queue_[op_type].has_operation(descriptor))
+      {
+        if (op->perform())
+        {
+          lock.unlock();
+          scheduler_.post_immediate_completion(op, is_continuation);
+          return;
+        }
+      }
+    }
+  }
+
+  bool first = op_queue_[op_type].enqueue_operation(descriptor, op);
+  scheduler_.work_started();
+  if (first)
+  {
+    ::pollfd& ev = add_pending_event_change(descriptor);
+    ev.events = POLLERR | POLLHUP;
+    if (op_type == read_op
+        || op_queue_[read_op].has_operation(descriptor))
+      ev.events |= POLLIN;
+    if (op_type == write_op
+        || op_queue_[write_op].has_operation(descriptor))
+      ev.events |= POLLOUT;
+    if (op_type == except_op
+        || op_queue_[except_op].has_operation(descriptor))
+      ev.events |= POLLPRI;
+    interrupter_.interrupt();
+  }
+}
+
+void dev_poll_reactor::cancel_ops(socket_type descriptor,
+    dev_poll_reactor::per_descriptor_data&)
+{
+  asio::detail::mutex::scoped_lock lock(mutex_);
+  cancel_ops_unlocked(descriptor, asio::error::operation_aborted);
+}
+
+void dev_poll_reactor::deregister_descriptor(socket_type descriptor,
+    dev_poll_reactor::per_descriptor_data&, bool)
+{
+  asio::detail::mutex::scoped_lock lock(mutex_);
+
+  // Remove the descriptor from /dev/poll.
+  ::pollfd& ev = add_pending_event_change(descriptor);
+  ev.events = POLLREMOVE;
+  interrupter_.interrupt();
+
+  // Cancel any outstanding operations associated with the descriptor.
+  cancel_ops_unlocked(descriptor, asio::error::operation_aborted);
+}
+
+void dev_poll_reactor::deregister_internal_descriptor(
+    socket_type descriptor, dev_poll_reactor::per_descriptor_data&)
+{
+  asio::detail::mutex::scoped_lock lock(mutex_);
+
+  // Remove the descriptor from /dev/poll. Since this function is only called
+  // during a fork, we can apply the change immediately.
+  ::pollfd ev = { 0, 0, 0 };
+  ev.fd = descriptor;
+  ev.events = POLLREMOVE;
+  ev.revents = 0;
+  ::write(dev_poll_fd_, &ev, sizeof(ev));
+
+  // Destroy all operations associated with the descriptor.
+  op_queue<operation> ops;
+  asio::error_code ec;
+  for (int i = 0; i < max_ops; ++i)
+    op_queue_[i].cancel_operations(descriptor, ops, ec);
+}
+
+void dev_poll_reactor::cleanup_descriptor_data(
+    dev_poll_reactor::per_descriptor_data&)
+{
+}
+
+void dev_poll_reactor::run(long usec, op_queue<operation>& ops)
+{
+  asio::detail::mutex::scoped_lock lock(mutex_);
+
+  // We can return immediately if there's no work to do and the reactor is
+  // not supposed to block.
+  if (usec == 0 && op_queue_[read_op].empty() && op_queue_[write_op].empty()
+      && op_queue_[except_op].empty() && timer_queues_.all_empty())
+    return;
+
+  // Write the pending event registration changes to the /dev/poll descriptor.
+  std::size_t events_size = sizeof(::pollfd) * pending_event_changes_.size();
+  if (events_size > 0)
+  {
+    errno = 0;
+    int result = ::write(dev_poll_fd_,
+        &pending_event_changes_[0], events_size);
+    if (result != static_cast<int>(events_size))
+    {
+      asio::error_code ec = asio::error_code(
+          errno, asio::error::get_system_category());
+      for (std::size_t i = 0; i < pending_event_changes_.size(); ++i)
+      {
+        int descriptor = pending_event_changes_[i].fd;
+        for (int j = 0; j < max_ops; ++j)
+          op_queue_[j].cancel_operations(descriptor, ops, ec);
+      }
+    }
+    pending_event_changes_.clear();
+    pending_event_change_index_.clear();
+  }
+
+  // Calculate timeout.
+  int timeout;
+  if (usec == 0)
+    timeout = 0;
+  else
+  {
+    timeout = (usec < 0) ? -1 : ((usec - 1) / 1000 + 1);
+    timeout = get_timeout(timeout);
+  }
+  lock.unlock();
+
+  // Block on the /dev/poll descriptor.
+  ::pollfd events[128] = { { 0, 0, 0 } };
+  ::dvpoll dp = { 0, 0, 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();
+
+  // 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;
+
+      // 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 =
+          op_queue_[except_op].perform_operations(descriptor, ops);
+      else
+        more_except = op_queue_[except_op].has_operation(descriptor);
+
+      if (events[i].events & (POLLIN | POLLERR | POLLHUP))
+        more_reads = op_queue_[read_op].perform_operations(descriptor, ops);
+      else
+        more_reads = op_queue_[read_op].has_operation(descriptor);
+
+      if (events[i].events & (POLLOUT | POLLERR | POLLHUP))
+        more_writes = op_queue_[write_op].perform_operations(descriptor, ops);
+      else
+        more_writes = op_queue_[write_op].has_operation(descriptor);
+
+      if ((events[i].events & (POLLERR | POLLHUP)) != 0
+            && !more_except && !more_reads && !more_writes)
+      {
+        // If we have an event and no operations associated with the
+        // descriptor then we need to delete the descriptor from /dev/poll.
+        // The poll operation can produce POLLHUP or POLLERR events when there
+        // is no operation pending, so if we do not remove the descriptor we
+        // can end up in a tight polling loop.
+        ::pollfd ev = { 0, 0, 0 };
+        ev.fd = descriptor;
+        ev.events = POLLREMOVE;
+        ev.revents = 0;
+        ::write(dev_poll_fd_, &ev, sizeof(ev));
+      }
+      else
+      {
+        ::pollfd ev = { 0, 0, 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))
+        {
+          asio::error_code ec(errno,
+              asio::error::get_system_category());
+          for (int j = 0; j < max_ops; ++j)
+            op_queue_[j].cancel_operations(descriptor, ops, ec);
+        }
+      }
+    }
+  }
+  timer_queues_.get_ready_timers(ops);
+}
+
+void dev_poll_reactor::interrupt()
+{
+  interrupter_.interrupt();
+}
+
+int dev_poll_reactor::do_dev_poll_create()
+{
+  int fd = ::open("/dev/poll", O_RDWR);
+  if (fd == -1)
+  {
+    asio::error_code ec(errno,
+        asio::error::get_system_category());
+    asio::detail::throw_error(ec, "/dev/poll");
+  }
+  return fd;
+}
+
+void dev_poll_reactor::do_add_timer_queue(timer_queue_base& queue)
+{
+  mutex::scoped_lock lock(mutex_);
+  timer_queues_.insert(&queue);
+}
+
+void dev_poll_reactor::do_remove_timer_queue(timer_queue_base& queue)
+{
+  mutex::scoped_lock lock(mutex_);
+  timer_queues_.erase(&queue);
+}
+
+int dev_poll_reactor::get_timeout(int msec)
+{
+  // 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.
+  const int max_msec = 5 * 60 * 1000;
+  return timer_queues_.wait_duration_msec(
+      (msec < 0 || max_msec < msec) ? max_msec : msec);
+}
+
+void dev_poll_reactor::cancel_ops_unlocked(socket_type descriptor,
+    const asio::error_code& ec)
+{
+  bool need_interrupt = false;
+  op_queue<operation> ops;
+  for (int i = 0; i < max_ops; ++i)
+    need_interrupt = op_queue_[i].cancel_operations(
+        descriptor, ops, ec) || need_interrupt;
+  scheduler_.post_deferred_completions(ops);
+  if (need_interrupt)
+    interrupter_.interrupt();
+}
+
+::pollfd& dev_poll_reactor::add_pending_event_change(int descriptor)
+{
+  hash_map<int, std::size_t>::iterator iter
+    = pending_event_change_index_.find(descriptor);
+  if (iter == pending_event_change_index_.end())
+  {
+    std::size_t index = pending_event_changes_.size();
+    pending_event_changes_.reserve(pending_event_changes_.size() + 1);
+    pending_event_change_index_.insert(std::make_pair(descriptor, index));
+    pending_event_changes_.push_back(::pollfd());
+    pending_event_changes_[index].fd = descriptor;
+    pending_event_changes_[index].revents = 0;
+    return pending_event_changes_[index];
+  }
+  else
+  {
+    return pending_event_changes_[iter->second];
+  }
+}
+
+} // namespace detail
+} // namespace asio
+
+#include "asio/detail/pop_options.hpp"
+
+#endif // defined(ASIO_HAS_DEV_POLL)
+
+#endif // ASIO_DETAIL_IMPL_DEV_POLL_REACTOR_IPP