summaryrefslogtreecommitdiff
path: root/boost/asio/detail/impl/signal_set_service.ipp
diff options
context:
space:
mode:
authorAnas Nashif <anas.nashif@intel.com>2012-10-30 19:57:26 (GMT)
committerAnas Nashif <anas.nashif@intel.com>2012-10-30 19:57:26 (GMT)
commit1a78a62555be32868418fe52f8e330c9d0f95d5a (patch)
treed3765a80e7d3b9640ec2e930743630cd6b9fce2b /boost/asio/detail/impl/signal_set_service.ipp
downloadboost-1a78a62555be32868418fe52f8e330c9d0f95d5a.zip
boost-1a78a62555be32868418fe52f8e330c9d0f95d5a.tar.gz
boost-1a78a62555be32868418fe52f8e330c9d0f95d5a.tar.bz2
Imported Upstream version 1.49.0upstream/1.49.0
Diffstat (limited to 'boost/asio/detail/impl/signal_set_service.ipp')
-rw-r--r--boost/asio/detail/impl/signal_set_service.ipp593
1 files changed, 593 insertions, 0 deletions
diff --git a/boost/asio/detail/impl/signal_set_service.ipp b/boost/asio/detail/impl/signal_set_service.ipp
new file mode 100644
index 0000000..0b57007
--- /dev/null
+++ b/boost/asio/detail/impl/signal_set_service.ipp
@@ -0,0 +1,593 @@
+//
+// detail/impl/signal_set_service.ipp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// 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)
+//
+
+#ifndef BOOST_ASIO_DETAIL_IMPL_SIGNAL_SET_SERVICE_IPP
+#define BOOST_ASIO_DETAIL_IMPL_SIGNAL_SET_SERVICE_IPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#include <cstring>
+#include <boost/asio/detail/reactor.hpp>
+#include <boost/asio/detail/signal_blocker.hpp>
+#include <boost/asio/detail/signal_set_service.hpp>
+#include <boost/asio/detail/static_mutex.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+struct signal_state
+{
+ // Mutex used for protecting global state.
+ static_mutex mutex_;
+
+ // The read end of the pipe used for signal notifications.
+ int read_descriptor_;
+
+ // The write end of the pipe used for signal notifications.
+ int write_descriptor_;
+
+ // Whether the signal state has been prepared for a fork.
+ bool fork_prepared_;
+
+ // The head of a linked list of all signal_set_service instances.
+ class signal_set_service* service_list_;
+
+ // A count of the number of objects that are registered for each signal.
+ std::size_t registration_count_[max_signal_number];
+};
+
+signal_state* get_signal_state()
+{
+ static signal_state state = {
+ BOOST_ASIO_STATIC_MUTEX_INIT, -1, -1, false, 0, { 0 } };
+ return &state;
+}
+
+void asio_signal_handler(int signal_number)
+{
+#if defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ signal_set_service::deliver_signal(signal_number);
+#else // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ int saved_errno = errno;
+ signal_state* state = get_signal_state();
+ int result = ::write(state->write_descriptor_,
+ &signal_number, sizeof(signal_number));
+ (void)result;
+ errno = saved_errno;
+#endif // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+
+#if defined(BOOST_ASIO_HAS_SIGNAL) && !defined(BOOST_ASIO_HAS_SIGACTION)
+ ::signal(signal_number, asio_signal_handler);
+#endif // defined(BOOST_ASIO_HAS_SIGNAL) && !defined(BOOST_ASIO_HAS_SIGACTION)
+}
+
+#if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+class signal_set_service::pipe_read_op : public reactor_op
+{
+public:
+ pipe_read_op()
+ : reactor_op(&pipe_read_op::do_perform, pipe_read_op::do_complete)
+ {
+ }
+
+ static bool do_perform(reactor_op*)
+ {
+ signal_state* state = get_signal_state();
+
+ int fd = state->read_descriptor_;
+ int signal_number = 0;
+ while (::read(fd, &signal_number, sizeof(int)) == sizeof(int))
+ if (signal_number >= 0 && signal_number < max_signal_number)
+ signal_set_service::deliver_signal(signal_number);
+
+ return false;
+ }
+
+ static void do_complete(io_service_impl* /*owner*/, operation* base,
+ const boost::system::error_code& /*ec*/,
+ std::size_t /*bytes_transferred*/)
+ {
+ pipe_read_op* o(static_cast<pipe_read_op*>(base));
+ delete o;
+ }
+};
+#endif // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+
+signal_set_service::signal_set_service(
+ boost::asio::io_service& io_service)
+ : io_service_(boost::asio::use_service<io_service_impl>(io_service)),
+#if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ reactor_(boost::asio::use_service<reactor>(io_service)),
+#endif // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ next_(0),
+ prev_(0)
+{
+ get_signal_state()->mutex_.init();
+
+#if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ reactor_.init_task();
+#endif // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+
+ for (int i = 0; i < max_signal_number; ++i)
+ registrations_[i] = 0;
+
+ add_service(this);
+}
+
+signal_set_service::~signal_set_service()
+{
+ remove_service(this);
+}
+
+void signal_set_service::shutdown_service()
+{
+ remove_service(this);
+
+ op_queue<operation> ops;
+
+ for (int i = 0; i < max_signal_number; ++i)
+ {
+ registration* reg = registrations_[i];
+ while (reg)
+ {
+ ops.push(*reg->queue_);
+ reg = reg->next_in_table_;
+ }
+ }
+
+ io_service_.abandon_operations(ops);
+}
+
+void signal_set_service::fork_service(
+ boost::asio::io_service::fork_event fork_ev)
+{
+#if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ signal_state* state = get_signal_state();
+ static_mutex::scoped_lock lock(state->mutex_);
+
+ switch (fork_ev)
+ {
+ case boost::asio::io_service::fork_prepare:
+ reactor_.deregister_internal_descriptor(
+ state->read_descriptor_, reactor_data_);
+ state->fork_prepared_ = true;
+ break;
+ case boost::asio::io_service::fork_parent:
+ state->fork_prepared_ = false;
+ reactor_.register_internal_descriptor(reactor::read_op,
+ state->read_descriptor_, reactor_data_, new pipe_read_op);
+ break;
+ case boost::asio::io_service::fork_child:
+ if (state->fork_prepared_)
+ {
+ boost::asio::detail::signal_blocker blocker;
+ close_descriptors();
+ open_descriptors();
+ state->fork_prepared_ = false;
+ }
+ reactor_.register_internal_descriptor(reactor::read_op,
+ state->read_descriptor_, reactor_data_, new pipe_read_op);
+ break;
+ default:
+ break;
+ }
+#else // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ (void)fork_ev;
+#endif // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+}
+
+void signal_set_service::construct(
+ signal_set_service::implementation_type& impl)
+{
+ impl.signals_ = 0;
+}
+
+void signal_set_service::destroy(
+ signal_set_service::implementation_type& impl)
+{
+ boost::system::error_code ignored_ec;
+ clear(impl, ignored_ec);
+ cancel(impl, ignored_ec);
+}
+
+boost::system::error_code signal_set_service::add(
+ signal_set_service::implementation_type& impl,
+ int signal_number, boost::system::error_code& ec)
+{
+ // Check that the signal number is valid.
+ if (signal_number < 0 || signal_number > max_signal_number)
+ {
+ ec = boost::asio::error::invalid_argument;
+ return ec;
+ }
+
+ signal_state* state = get_signal_state();
+ static_mutex::scoped_lock lock(state->mutex_);
+
+ // Find the appropriate place to insert the registration.
+ registration** insertion_point = &impl.signals_;
+ registration* next = impl.signals_;
+ while (next && next->signal_number_ < signal_number)
+ {
+ insertion_point = &next->next_in_set_;
+ next = next->next_in_set_;
+ }
+
+ // Only do something if the signal is not already registered.
+ if (next == 0 || next->signal_number_ != signal_number)
+ {
+ registration* new_registration = new registration;
+
+#if defined(BOOST_ASIO_HAS_SIGNAL) || defined(BOOST_ASIO_HAS_SIGACTION)
+ // Register for the signal if we're the first.
+ if (state->registration_count_[signal_number] == 0)
+ {
+# if defined(BOOST_ASIO_HAS_SIGACTION)
+ using namespace std; // For memset.
+ struct sigaction sa;
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_handler = asio_signal_handler;
+ sigfillset(&sa.sa_mask);
+ if (::sigaction(signal_number, &sa, 0) == -1)
+# else // defined(BOOST_ASIO_HAS_SIGACTION)
+ if (::signal(signal_number, asio_signal_handler) == SIG_ERR)
+# endif // defined(BOOST_ASIO_HAS_SIGACTION)
+ {
+# if defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ ec = boost::asio::error::invalid_argument;
+# else // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ ec = boost::system::error_code(errno,
+ boost::asio::error::get_system_category());
+# endif // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ delete new_registration;
+ return ec;
+ }
+ }
+#endif // defined(BOOST_ASIO_HAS_SIGNAL) || defined(BOOST_ASIO_HAS_SIGACTION)
+
+ // Record the new registration in the set.
+ new_registration->signal_number_ = signal_number;
+ new_registration->queue_ = &impl.queue_;
+ new_registration->next_in_set_ = next;
+ *insertion_point = new_registration;
+
+ // Insert registration into the registration table.
+ new_registration->next_in_table_ = registrations_[signal_number];
+ if (registrations_[signal_number])
+ registrations_[signal_number]->prev_in_table_ = new_registration;
+ registrations_[signal_number] = new_registration;
+
+ ++state->registration_count_[signal_number];
+ }
+
+ ec = boost::system::error_code();
+ return ec;
+}
+
+boost::system::error_code signal_set_service::remove(
+ signal_set_service::implementation_type& impl,
+ int signal_number, boost::system::error_code& ec)
+{
+ // Check that the signal number is valid.
+ if (signal_number < 0 || signal_number > max_signal_number)
+ {
+ ec = boost::asio::error::invalid_argument;
+ return ec;
+ }
+
+ signal_state* state = get_signal_state();
+ static_mutex::scoped_lock lock(state->mutex_);
+
+ // Find the signal number in the list of registrations.
+ registration** deletion_point = &impl.signals_;
+ registration* reg = impl.signals_;
+ while (reg && reg->signal_number_ < signal_number)
+ {
+ deletion_point = &reg->next_in_set_;
+ reg = reg->next_in_set_;
+ }
+
+ if (reg != 0 && reg->signal_number_ == signal_number)
+ {
+#if defined(BOOST_ASIO_HAS_SIGNAL) || defined(BOOST_ASIO_HAS_SIGACTION)
+ // Set signal handler back to the default if we're the last.
+ if (state->registration_count_[signal_number] == 1)
+ {
+# if defined(BOOST_ASIO_HAS_SIGACTION)
+ using namespace std; // For memset.
+ struct sigaction sa;
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_handler = SIG_DFL;
+ if (::sigaction(signal_number, &sa, 0) == -1)
+# else // defined(BOOST_ASIO_HAS_SIGACTION)
+ if (::signal(signal_number, SIG_DFL) == SIG_ERR)
+# endif // defined(BOOST_ASIO_HAS_SIGACTION)
+ {
+# if defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ ec = boost::asio::error::invalid_argument;
+# else // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ ec = boost::system::error_code(errno,
+ boost::asio::error::get_system_category());
+# endif // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ return ec;
+ }
+ }
+#endif // defined(BOOST_ASIO_HAS_SIGNAL) || defined(BOOST_ASIO_HAS_SIGACTION)
+
+ // Remove the registration from the set.
+ *deletion_point = reg->next_in_set_;
+
+ // Remove the registration from the registration table.
+ if (registrations_[signal_number] == reg)
+ registrations_[signal_number] = reg->next_in_table_;
+ if (reg->prev_in_table_)
+ reg->prev_in_table_->next_in_table_ = reg->next_in_table_;
+ if (reg->next_in_table_)
+ reg->next_in_table_->prev_in_table_ = reg->prev_in_table_;
+
+ --state->registration_count_[signal_number];
+
+ delete reg;
+ }
+
+ ec = boost::system::error_code();
+ return ec;
+}
+
+boost::system::error_code signal_set_service::clear(
+ signal_set_service::implementation_type& impl,
+ boost::system::error_code& ec)
+{
+ signal_state* state = get_signal_state();
+ static_mutex::scoped_lock lock(state->mutex_);
+
+ while (registration* reg = impl.signals_)
+ {
+#if defined(BOOST_ASIO_HAS_SIGNAL) || defined(BOOST_ASIO_HAS_SIGACTION)
+ // Set signal handler back to the default if we're the last.
+ if (state->registration_count_[reg->signal_number_] == 1)
+ {
+# if defined(BOOST_ASIO_HAS_SIGACTION)
+ using namespace std; // For memset.
+ struct sigaction sa;
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_handler = SIG_DFL;
+ if (::sigaction(reg->signal_number_, &sa, 0) == -1)
+# else // defined(BOOST_ASIO_HAS_SIGACTION)
+ if (::signal(reg->signal_number_, SIG_DFL) == SIG_ERR)
+# endif // defined(BOOST_ASIO_HAS_SIGACTION)
+ {
+# if defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ ec = boost::asio::error::invalid_argument;
+# else // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ ec = boost::system::error_code(errno,
+ boost::asio::error::get_system_category());
+# endif // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
+ return ec;
+ }
+ }
+#endif // defined(BOOST_ASIO_HAS_SIGNAL) || defined(BOOST_ASIO_HAS_SIGACTION)
+
+ // Remove the registration from the registration table.
+ if (registrations_[reg->signal_number_] == reg)
+ registrations_[reg->signal_number_] = reg->next_in_table_;
+ if (reg->prev_in_table_)
+ reg->prev_in_table_->next_in_table_ = reg->next_in_table_;
+ if (reg->next_in_table_)
+ reg->next_in_table_->prev_in_table_ = reg->prev_in_table_;
+
+ --state->registration_count_[reg->signal_number_];
+
+ impl.signals_ = reg->next_in_set_;
+ delete reg;
+ }
+
+ ec = boost::system::error_code();
+ return ec;
+}
+
+boost::system::error_code signal_set_service::cancel(
+ signal_set_service::implementation_type& impl,
+ boost::system::error_code& ec)
+{
+ BOOST_ASIO_HANDLER_OPERATION(("signal_set", &impl, "cancel"));
+
+ op_queue<operation> ops;
+ {
+ signal_state* state = get_signal_state();
+ static_mutex::scoped_lock lock(state->mutex_);
+
+ while (signal_op* op = impl.queue_.front())
+ {
+ op->ec_ = boost::asio::error::operation_aborted;
+ impl.queue_.pop();
+ ops.push(op);
+ }
+ }
+
+ io_service_.post_deferred_completions(ops);
+
+ ec = boost::system::error_code();
+ return ec;
+}
+
+void signal_set_service::deliver_signal(int signal_number)
+{
+ signal_state* state = get_signal_state();
+ static_mutex::scoped_lock lock(state->mutex_);
+
+ signal_set_service* service = state->service_list_;
+ while (service)
+ {
+ op_queue<operation> ops;
+
+ registration* reg = service->registrations_[signal_number];
+ while (reg)
+ {
+ if (reg->queue_->empty())
+ {
+ ++reg->undelivered_;
+ }
+ else
+ {
+ while (signal_op* op = reg->queue_->front())
+ {
+ op->signal_number_ = signal_number;
+ reg->queue_->pop();
+ ops.push(op);
+ }
+ }
+
+ reg = reg->next_in_table_;
+ }
+
+ service->io_service_.post_deferred_completions(ops);
+
+ service = service->next_;
+ }
+}
+
+void signal_set_service::add_service(signal_set_service* service)
+{
+ signal_state* state = get_signal_state();
+ static_mutex::scoped_lock lock(state->mutex_);
+
+#if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ // If this is the first service to be created, open a new pipe.
+ if (state->service_list_ == 0)
+ open_descriptors();
+#endif // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+
+ // Insert service into linked list of all services.
+ service->next_ = state->service_list_;
+ service->prev_ = 0;
+ if (state->service_list_)
+ state->service_list_->prev_ = service;
+ state->service_list_ = service;
+
+#if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ // Register for pipe readiness notifications.
+ service->reactor_.register_internal_descriptor(reactor::read_op,
+ state->read_descriptor_, service->reactor_data_, new pipe_read_op);
+#endif // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+}
+
+void signal_set_service::remove_service(signal_set_service* service)
+{
+ signal_state* state = get_signal_state();
+ static_mutex::scoped_lock lock(state->mutex_);
+
+ if (service->next_ || service->prev_ || state->service_list_ == service)
+ {
+#if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ // Disable the pipe readiness notifications.
+ service->reactor_.deregister_descriptor(
+ state->read_descriptor_, service->reactor_data_, false);
+#endif // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+
+ // Remove service from linked list of all services.
+ if (state->service_list_ == service)
+ state->service_list_ = service->next_;
+ if (service->prev_)
+ service->prev_->next_ = service->next_;
+ if (service->next_)
+ service->next_->prev_= service->prev_;
+ service->next_ = 0;
+ service->prev_ = 0;
+
+#if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ // If this is the last service to be removed, close the pipe.
+ if (state->service_list_ == 0)
+ close_descriptors();
+#endif // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ }
+}
+
+void signal_set_service::open_descriptors()
+{
+#if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ signal_state* state = get_signal_state();
+
+ int pipe_fds[2];
+ if (::pipe(pipe_fds) == 0)
+ {
+ state->read_descriptor_ = pipe_fds[0];
+ ::fcntl(state->read_descriptor_, F_SETFL, O_NONBLOCK);
+
+ state->write_descriptor_ = pipe_fds[1];
+ ::fcntl(state->write_descriptor_, F_SETFL, O_NONBLOCK);
+
+#if defined(FD_CLOEXEC)
+ ::fcntl(state->read_descriptor_, F_SETFD, FD_CLOEXEC);
+ ::fcntl(state->write_descriptor_, F_SETFD, FD_CLOEXEC);
+#endif // defined(FD_CLOEXEC)
+ }
+ else
+ {
+ boost::system::error_code ec(errno,
+ boost::asio::error::get_system_category());
+ boost::asio::detail::throw_error(ec, "signal_set_service pipe");
+ }
+#endif // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+}
+
+void signal_set_service::close_descriptors()
+{
+#if !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+ signal_state* state = get_signal_state();
+
+ if (state->read_descriptor_ != -1)
+ ::close(state->read_descriptor_);
+ state->read_descriptor_ = -1;
+
+ if (state->write_descriptor_ != -1)
+ ::close(state->write_descriptor_);
+ state->write_descriptor_ = -1;
+#endif // !defined(BOOST_WINDOWS) && !defined(__CYGWIN__)
+}
+
+void signal_set_service::start_wait_op(
+ signal_set_service::implementation_type& impl, signal_op* op)
+{
+ io_service_.work_started();
+
+ signal_state* state = get_signal_state();
+ static_mutex::scoped_lock lock(state->mutex_);
+
+ registration* reg = impl.signals_;
+ while (reg)
+ {
+ if (reg->undelivered_ > 0)
+ {
+ --reg->undelivered_;
+ io_service_.post_deferred_completion(op);
+ return;
+ }
+
+ reg = reg->next_in_set_;
+ }
+
+ impl.queue_.push(op);
+}
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_IMPL_SIGNAL_SET_SERVICE_IPP