1 files changed, 316 insertions, 45 deletions
diff --git a/3rdParty/Boost/src/boost/asio/detail/impl/epoll_reactor.ipp b/3rdParty/Boost/src/boost/asio/detail/impl/epoll_reactor.ipp
index 5afb891..073bd08 100644
--- a/3rdParty/Boost/src/boost/asio/detail/impl/epoll_reactor.ipp
+++ b/3rdParty/Boost/src/boost/asio/detail/impl/epoll_reactor.ipp
@@ -2,7 +2,7 @@
 // detail/impl/epoll_reactor.ipp
 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 //
-// Copyright (c) 2003-2011 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+// Copyright (c) 2003-2012 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)
@@ -39,13 +39,9 @@ epoll_reactor::epoll_reactor(boost::asio::io_service& io_service)
   : boost::asio::detail::service_base<epoll_reactor>(io_service),
     io_service_(use_service<io_service_impl>(io_service)),
     mutex_(),
-    epoll_fd_(do_epoll_create()),
-#if defined(BOOST_ASIO_HAS_TIMERFD)
-    timer_fd_(timerfd_create(CLOCK_MONOTONIC, 0)),
-#else // defined(BOOST_ASIO_HAS_TIMERFD)
-    timer_fd_(-1),
-#endif // defined(BOOST_ASIO_HAS_TIMERFD)
     interrupter_(),
+    epoll_fd_(do_epoll_create()),
+    timer_fd_(do_timerfd_create()),
     shutdown_(false)
 {
   // Add the interrupter's descriptor to epoll.
@@ -66,7 +62,8 @@ epoll_reactor::epoll_reactor(boost::asio::io_service& io_service)
 
 epoll_reactor::~epoll_reactor()
 {
-  close(epoll_fd_);
+  if (epoll_fd_ != -1)
+    close(epoll_fd_);
   if (timer_fd_ != -1)
     close(timer_fd_);
 }
@@ -88,6 +85,59 @@ void epoll_reactor::shutdown_service()
   }
 
   timer_queues_.get_all_timers(ops);
+
+  io_service_.abandon_operations(ops);
+}
+
+void epoll_reactor::fork_service(boost::asio::io_service::fork_event fork_ev)
+{
+  if (fork_ev == boost::asio::io_service::fork_child)
+  {
+    if (epoll_fd_ != -1)
+      ::close(epoll_fd_);
+    epoll_fd_ = -1;
+    epoll_fd_ = do_epoll_create();
+
+    if (timer_fd_ != -1)
+      ::close(timer_fd_);
+    timer_fd_ = -1;
+    timer_fd_ = do_timerfd_create();
+
+    interrupter_.recreate();
+
+    // Add the interrupter's descriptor to epoll.
+    epoll_event ev = { 0, { 0 } };
+    ev.events = EPOLLIN | EPOLLERR | EPOLLET;
+    ev.data.ptr = &interrupter_;
+    epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, interrupter_.read_descriptor(), &ev);
+    interrupter_.interrupt();
+
+    // Add the timer descriptor to epoll.
+    if (timer_fd_ != -1)
+    {
+      ev.events = EPOLLIN | EPOLLERR;
+      ev.data.ptr = &timer_fd_;
+      epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, timer_fd_, &ev);
+    }
+
+    update_timeout();
+
+    // Re-register all descriptors with epoll.
+    mutex::scoped_lock descriptors_lock(registered_descriptors_mutex_);
+    for (descriptor_state* state = registered_descriptors_.first();
+        state != 0; state = state->next_)
+    {
+      ev.events = state->registered_events_;
+      ev.data.ptr = state;
+      int result = epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, state->descriptor_, &ev);
+      if (result != 0)
+      {
+        boost::system::error_code ec(errno,
+            boost::asio::error::get_system_category());
+        boost::asio::detail::throw_error(ec, "epoll re-registration");
+      }
+    }
+  }
 }
 
 void epoll_reactor::init_task()
@@ -98,15 +148,19 @@ void epoll_reactor::init_task()
 int epoll_reactor::register_descriptor(socket_type descriptor,
     epoll_reactor::per_descriptor_data& descriptor_data)
 {
-  mutex::scoped_lock lock(registered_descriptors_mutex_);
+  descriptor_data = allocate_descriptor_state();
 
-  descriptor_data = registered_descriptors_.alloc();
-  descriptor_data->shutdown_ = false;
+  {
+    mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
 
-  lock.unlock();
+    descriptor_data->reactor_ = this;
+    descriptor_data->descriptor_ = descriptor;
+    descriptor_data->shutdown_ = false;
+  }
 
   epoll_event ev = { 0, { 0 } };
-  ev.events = EPOLLIN | EPOLLERR | EPOLLHUP | EPOLLOUT | EPOLLPRI | EPOLLET;
+  ev.events = EPOLLIN | EPOLLERR | EPOLLHUP | EPOLLPRI | EPOLLET;
+  descriptor_data->registered_events_ = ev.events;
   ev.data.ptr = descriptor_data;
   int result = epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, descriptor, &ev);
   if (result != 0)
@@ -115,6 +169,40 @@ int epoll_reactor::register_descriptor(socket_type descriptor,
   return 0;
 }
 
+int epoll_reactor::register_internal_descriptor(
+    int op_type, socket_type descriptor,
+    epoll_reactor::per_descriptor_data& descriptor_data, reactor_op* op)
+{
+  descriptor_data = allocate_descriptor_state();
+
+  {
+    mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
+
+    descriptor_data->reactor_ = this;
+    descriptor_data->descriptor_ = descriptor;
+    descriptor_data->shutdown_ = false;
+    descriptor_data->op_queue_[op_type].push(op);
+  }
+
+  epoll_event ev = { 0, { 0 } };
+  ev.events = EPOLLIN | EPOLLERR | EPOLLHUP | EPOLLPRI | EPOLLET;
+  descriptor_data->registered_events_ = ev.events;
+  ev.data.ptr = descriptor_data;
+  int result = epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, descriptor, &ev);
+  if (result != 0)
+    return errno;
+
+  return 0;
+}
+
+void epoll_reactor::move_descriptor(socket_type,
+    epoll_reactor::per_descriptor_data& target_descriptor_data,
+    epoll_reactor::per_descriptor_data& source_descriptor_data)
+{
+  target_descriptor_data = source_descriptor_data;
+  source_descriptor_data = 0;
+}
+
 void epoll_reactor::start_op(int op_type, socket_type descriptor,
     epoll_reactor::per_descriptor_data& descriptor_data,
     reactor_op* op, bool allow_speculative)
@@ -146,12 +234,37 @@ void epoll_reactor::start_op(int op_type, socket_type descriptor,
         io_service_.post_immediate_completion(op);
         return;
       }
+
+      if (op_type == write_op)
+      {
+        if ((descriptor_data->registered_events_ & EPOLLOUT) == 0)
+        {
+          epoll_event ev = { 0, { 0 } };
+          ev.events = descriptor_data->registered_events_ | EPOLLOUT;
+          ev.data.ptr = descriptor_data;
+          if (epoll_ctl(epoll_fd_, EPOLL_CTL_MOD, descriptor, &ev) == 0)
+          {
+            descriptor_data->registered_events_ |= ev.events;
+          }
+          else
+          {
+            op->ec_ = boost::system::error_code(errno,
+                boost::asio::error::get_system_category());
+            io_service_.post_immediate_completion(op);
+            return;
+          }
+        }
+      }
     }
     else
     {
+      if (op_type == write_op)
+      {
+        descriptor_data->registered_events_ |= EPOLLOUT;
+      }
+
       epoll_event ev = { 0, { 0 } };
-      ev.events = EPOLLIN | EPOLLERR | EPOLLHUP
-        | EPOLLOUT | EPOLLPRI | EPOLLET;
+      ev.events = descriptor_data->registered_events_;
       ev.data.ptr = descriptor_data;
       epoll_ctl(epoll_fd_, EPOLL_CTL_MOD, descriptor, &ev);
     }
@@ -185,19 +298,26 @@ void epoll_reactor::cancel_ops(socket_type,
   io_service_.post_deferred_completions(ops);
 }
 
-void epoll_reactor::close_descriptor(socket_type,
-    epoll_reactor::per_descriptor_data& descriptor_data)
+void epoll_reactor::deregister_descriptor(socket_type descriptor,
+    epoll_reactor::per_descriptor_data& descriptor_data, bool closing)
 {
   if (!descriptor_data)
     return;
 
   mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-  mutex::scoped_lock descriptors_lock(registered_descriptors_mutex_);
 
   if (!descriptor_data->shutdown_)
   {
-    // Remove the descriptor from the set of known descriptors. The descriptor
-    // will be automatically removed from the epoll set when it is closed.
+    if (closing)
+    {
+      // The descriptor will be automatically removed from the epoll set when
+      // it is closed.
+    }
+    else
+    {
+      epoll_event ev = { 0, { 0 } };
+      epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, descriptor, &ev);
+    }
 
     op_queue<operation> ops;
     for (int i = 0; i < max_ops; ++i)
@@ -210,21 +330,53 @@ void epoll_reactor::close_descriptor(socket_type,
       }
     }
 
+    descriptor_data->descriptor_ = -1;
     descriptor_data->shutdown_ = true;
 
     descriptor_lock.unlock();
 
-    registered_descriptors_.free(descriptor_data);
+    free_descriptor_state(descriptor_data);
     descriptor_data = 0;
 
-    descriptors_lock.unlock();
-
     io_service_.post_deferred_completions(ops);
   }
 }
 
+void epoll_reactor::deregister_internal_descriptor(socket_type descriptor,
+    epoll_reactor::per_descriptor_data& descriptor_data)
+{
+  if (!descriptor_data)
+    return;
+
+  mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
+
+  if (!descriptor_data->shutdown_)
+  {
+    epoll_event ev = { 0, { 0 } };
+    epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, descriptor, &ev);
+
+    op_queue<operation> ops;
+    for (int i = 0; i < max_ops; ++i)
+      ops.push(descriptor_data->op_queue_[i]);
+
+    descriptor_data->descriptor_ = -1;
+    descriptor_data->shutdown_ = true;
+
+    descriptor_lock.unlock();
+
+    free_descriptor_state(descriptor_data);
+    descriptor_data = 0;
+  }
+}
+
 void epoll_reactor::run(bool block, op_queue<operation>& ops)
 {
+  // This code relies on the fact that the task_io_service queues the reactor
+  // task behind all descriptor operations generated by this function. This
+  // means, that by the time we reach this point, any previously returned
+  // descriptor operations have already been dequeued. Therefore it is now safe
+  // for us to reuse and return them for the task_io_service to queue again.
+
   // Calculate a timeout only if timerfd is not used.
   int timeout;
   if (timer_fd_ != -1)
@@ -271,28 +423,12 @@ void epoll_reactor::run(bool block, op_queue<operation>& ops)
 #endif // defined(BOOST_ASIO_HAS_TIMERFD)
     else
     {
+      // The descriptor operation doesn't count as work in and of itself, so we
+      // don't call work_started() here. This still allows the io_service to
+      // stop if the only remaining operations are descriptor operations.
       descriptor_state* descriptor_data = static_cast<descriptor_state*>(ptr);
-      mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-      // Exception operations must be processed first to ensure that any
-      // out-of-band data is read before normal data.
-      static const int flag[max_ops] = { EPOLLIN, EPOLLOUT, EPOLLPRI };
-      for (int j = max_ops - 1; j >= 0; --j)
-      {
-        if (events[i].events & (flag[j] | EPOLLERR | EPOLLHUP))
-        {
-          while (reactor_op* op = descriptor_data->op_queue_[j].front())
-          {
-            if (op->perform())
-            {
-              descriptor_data->op_queue_[j].pop();
-              ops.push(op);
-            }
-            else
-              break;
-          }
-        }
-      }
+      descriptor_data->set_ready_events(events[i].events);
+      ops.push(descriptor_data);
     }
   }
 
@@ -323,16 +459,65 @@ void epoll_reactor::interrupt()
 
 int epoll_reactor::do_epoll_create()
 {
-  int fd = epoll_create(epoll_size);
+#if defined(EPOLL_CLOEXEC)
+  int fd = epoll_create1(EPOLL_CLOEXEC);
+#else // defined(EPOLL_CLOEXEC)
+  int fd = -1;
+  errno = EINVAL;
+#endif // defined(EPOLL_CLOEXEC)
+
+  if (fd == -1 && (errno == EINVAL || errno == ENOSYS))
+  {
+    fd = epoll_create(epoll_size);
+    if (fd != -1)
+      ::fcntl(fd, F_SETFD, FD_CLOEXEC);
+  }
+
   if (fd == -1)
   {
     boost::system::error_code ec(errno,
         boost::asio::error::get_system_category());
     boost::asio::detail::throw_error(ec, "epoll");
   }
+
   return fd;
 }
 
+int epoll_reactor::do_timerfd_create()
+{
+#if defined(BOOST_ASIO_HAS_TIMERFD)
+# if defined(TFD_CLOEXEC)
+  int fd = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC);
+# else // defined(TFD_CLOEXEC)
+  int fd = -1;
+  errno = EINVAL;
+# endif // defined(TFD_CLOEXEC)
+
+  if (fd == -1 && errno == EINVAL)
+  {
+    fd = timerfd_create(CLOCK_MONOTONIC, 0);
+    if (fd != -1)
+      ::fcntl(fd, F_SETFD, FD_CLOEXEC);
+  }
+
+  return fd;
+#else // defined(BOOST_ASIO_HAS_TIMERFD)
+  return -1;
+#endif // defined(BOOST_ASIO_HAS_TIMERFD)
+}
+
+epoll_reactor::descriptor_state* epoll_reactor::allocate_descriptor_state()
+{
+  mutex::scoped_lock descriptors_lock(registered_descriptors_mutex_);
+  return registered_descriptors_.alloc();
+}
+
+void epoll_reactor::free_descriptor_state(epoll_reactor::descriptor_state* s)
+{
+  mutex::scoped_lock descriptors_lock(registered_descriptors_mutex_);
+  registered_descriptors_.free(s);
+}
+
 void epoll_reactor::do_add_timer_queue(timer_queue_base& queue)
 {
   mutex::scoped_lock lock(mutex_);
@@ -381,6 +566,92 @@ int epoll_reactor::get_timeout(itimerspec& ts)
 }
 #endif // defined(BOOST_ASIO_HAS_TIMERFD)
 
+struct epoll_reactor::perform_io_cleanup_on_block_exit
+{
+  explicit perform_io_cleanup_on_block_exit(epoll_reactor* r)
+    : reactor_(r), first_op_(0)
+  {
+  }
+
+  ~perform_io_cleanup_on_block_exit()
+  {
+    if (first_op_)
+    {
+      // Post the remaining completed operations for invocation.
+      if (!ops_.empty())
+        reactor_->io_service_.post_deferred_completions(ops_);
+
+      // A user-initiated operation has completed, but there's no need to
+      // explicitly call work_finished() here. Instead, we'll take advantage of
+      // the fact that the task_io_service will call work_finished() once we
+      // return.
+    }
+    else
+    {
+      // No user-initiated operations have completed, so we need to compensate
+      // for the work_finished() call that the task_io_service will make once
+      // this operation returns.
+      reactor_->io_service_.work_started();
+    }
+  }
+
+  epoll_reactor* reactor_;
+  op_queue<operation> ops_;
+  operation* first_op_;
+};
+
+epoll_reactor::descriptor_state::descriptor_state()
+  : operation(&epoll_reactor::descriptor_state::do_complete)
+{
+}
+
+operation* epoll_reactor::descriptor_state::perform_io(uint32_t events)
+{
+  perform_io_cleanup_on_block_exit io_cleanup(reactor_);
+  mutex::scoped_lock descriptor_lock(mutex_);
+
+  // Exception operations must be processed first to ensure that any
+  // out-of-band data is read before normal data.
+  static const int flag[max_ops] = { EPOLLIN, EPOLLOUT, EPOLLPRI };
+  for (int j = max_ops - 1; j >= 0; --j)
+  {
+    if (events & (flag[j] | EPOLLERR | EPOLLHUP))
+    {
+      while (reactor_op* op = op_queue_[j].front())
+      {
+        if (op->perform())
+        {
+          op_queue_[j].pop();
+          io_cleanup.ops_.push(op);
+        }
+        else
+          break;
+      }
+    }
+  }
+
+  // The first operation will be returned for completion now. The others will
+  // be posted for later by the io_cleanup object's destructor.
+  io_cleanup.first_op_ = io_cleanup.ops_.front();
+  io_cleanup.ops_.pop();
+  return io_cleanup.first_op_;
+}
+
+void epoll_reactor::descriptor_state::do_complete(
+    io_service_impl* owner, operation* base,
+    const boost::system::error_code& ec, std::size_t bytes_transferred)
+{
+  if (owner)
+  {
+    descriptor_state* descriptor_data = static_cast<descriptor_state*>(base);
+    uint32_t events = static_cast<uint32_t>(bytes_transferred);
+    if (operation* op = descriptor_data->perform_io(events))
+    {
+      op->complete(*owner, ec, 0);
+    }
+  }
+}
+
 } // namespace detail
 } // namespace asio
 } // namespace boost