Edit: /usr/include/boost/asio/basic_signal_set.hpp (19876B)
//
// basic_signal_set.hpp
// ~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2020 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_BASIC_SIGNAL_SET_HPP
#define BOOST_ASIO_BASIC_SIGNAL_SET_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
namespace boost {
namespace asio {
/// Provides signal functionality.
/**
* The basic_signal_set class provides the ability to perform an asynchronous
* wait for one or more signals to occur.
*
* @par Thread Safety
* @e Distinct @e objects: Safe.@n
* @e Shared @e objects: Unsafe.
*
* @par Example
* Performing an asynchronous wait:
* @code
* void handler(
* const boost::system::error_code& error,
* int signal_number)
* {
* if (!error)
* {
* // A signal occurred.
* }
* }
*
* ...
*
* // Construct a signal set registered for process termination.
* boost::asio::signal_set signals(my_context, SIGINT, SIGTERM);
*
* // Start an asynchronous wait for one of the signals to occur.
* signals.async_wait(handler);
* @endcode
*
* @par Queueing of signal notifications
*
* If a signal is registered with a signal_set, and the signal occurs when
* there are no waiting handlers, then the signal notification is queued. The
* next async_wait operation on that signal_set will dequeue the notification.
* If multiple notifications are queued, subsequent async_wait operations
* dequeue them one at a time. Signal notifications are dequeued in order of
* ascending signal number.
*
* If a signal number is removed from a signal_set (using the @c remove or @c
* erase member functions) then any queued notifications for that signal are
* discarded.
*
* @par Multiple registration of signals
*
* The same signal number may be registered with different signal_set objects.
* When the signal occurs, one handler is called for each signal_set object.
*
* Note that multiple registration only works for signals that are registered
* using Asio. The application must not also register a signal handler using
* functions such as @c signal() or @c sigaction().
*
* @par Signal masking on POSIX platforms
*
* POSIX allows signals to be blocked using functions such as @c sigprocmask()
* and @c pthread_sigmask(). For signals to be delivered, programs must ensure
* that any signals registered using signal_set objects are unblocked in at
* least one thread.
*/
template
class basic_signal_set
{
public:
/// The type of the executor associated with the object.
typedef Executor executor_type;
/// Rebinds the signal set type to another executor.
template
struct rebind_executor
{
/// The signal set type when rebound to the specified executor.
typedef basic_signal_set other;
};
/// Construct a signal set without adding any signals.
/**
* This constructor creates a signal set without registering for any signals.
*
* @param ex The I/O executor that the signal set will use, by default, to
* dispatch handlers for any asynchronous operations performed on the
* signal set.
*/
explicit basic_signal_set(const executor_type& ex)
: impl_(ex)
{
}
/// Construct a signal set without adding any signals.
/**
* This constructor creates a signal set without registering for any signals.
*
* @param context An execution context which provides the I/O executor that
* the signal set will use, by default, to dispatch handlers for any
* asynchronous operations performed on the signal set.
*/
template
explicit basic_signal_set(ExecutionContext& context,
typename enable_if<
is_convertible::value
>::type* = 0)
: impl_(context)
{
}
/// Construct a signal set and add one signal.
/**
* This constructor creates a signal set and registers for one signal.
*
* @param ex The I/O executor that the signal set will use, by default, to
* dispatch handlers for any asynchronous operations performed on the
* signal set.
*
* @param signal_number_1 The signal number to be added.
*
* @note This constructor is equivalent to performing:
* @code boost::asio::signal_set signals(ex);
* signals.add(signal_number_1); @endcode
*/
basic_signal_set(const executor_type& ex, int signal_number_1)
: impl_(ex)
{
boost::system::error_code ec;
impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
boost::asio::detail::throw_error(ec, "add");
}
/// Construct a signal set and add one signal.
/**
* This constructor creates a signal set and registers for one signal.
*
* @param context An execution context which provides the I/O executor that
* the signal set will use, by default, to dispatch handlers for any
* asynchronous operations performed on the signal set.
*
* @param signal_number_1 The signal number to be added.
*
* @note This constructor is equivalent to performing:
* @code boost::asio::signal_set signals(context);
* signals.add(signal_number_1); @endcode
*/
template
basic_signal_set(ExecutionContext& context, int signal_number_1,
typename enable_if<
is_convertible::value
>::type* = 0)
: impl_(context)
{
boost::system::error_code ec;
impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
boost::asio::detail::throw_error(ec, "add");
}
/// Construct a signal set and add two signals.
/**
* This constructor creates a signal set and registers for two signals.
*
* @param ex The I/O executor that the signal set will use, by default, to
* dispatch handlers for any asynchronous operations performed on the
* signal set.
*
* @param signal_number_1 The first signal number to be added.
*
* @param signal_number_2 The second signal number to be added.
*
* @note This constructor is equivalent to performing:
* @code boost::asio::signal_set signals(ex);
* signals.add(signal_number_1);
* signals.add(signal_number_2); @endcode
*/
basic_signal_set(const executor_type& ex, int signal_number_1,
int signal_number_2)
: impl_(ex)
{
boost::system::error_code ec;
impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
boost::asio::detail::throw_error(ec, "add");
impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
boost::asio::detail::throw_error(ec, "add");
}
/// Construct a signal set and add two signals.
/**
* This constructor creates a signal set and registers for two signals.
*
* @param context An execution context which provides the I/O executor that
* the signal set will use, by default, to dispatch handlers for any
* asynchronous operations performed on the signal set.
*
* @param signal_number_1 The first signal number to be added.
*
* @param signal_number_2 The second signal number to be added.
*
* @note This constructor is equivalent to performing:
* @code boost::asio::signal_set signals(context);
* signals.add(signal_number_1);
* signals.add(signal_number_2); @endcode
*/
template
basic_signal_set(ExecutionContext& context, int signal_number_1,
int signal_number_2,
typename enable_if<
is_convertible::value
>::type* = 0)
: impl_(context)
{
boost::system::error_code ec;
impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
boost::asio::detail::throw_error(ec, "add");
impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
boost::asio::detail::throw_error(ec, "add");
}
/// Construct a signal set and add three signals.
/**
* This constructor creates a signal set and registers for three signals.
*
* @param ex The I/O executor that the signal set will use, by default, to
* dispatch handlers for any asynchronous operations performed on the
* signal set.
*
* @param signal_number_1 The first signal number to be added.
*
* @param signal_number_2 The second signal number to be added.
*
* @param signal_number_3 The third signal number to be added.
*
* @note This constructor is equivalent to performing:
* @code boost::asio::signal_set signals(ex);
* signals.add(signal_number_1);
* signals.add(signal_number_2);
* signals.add(signal_number_3); @endcode
*/
basic_signal_set(const executor_type& ex, int signal_number_1,
int signal_number_2, int signal_number_3)
: impl_(ex)
{
boost::system::error_code ec;
impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
boost::asio::detail::throw_error(ec, "add");
impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
boost::asio::detail::throw_error(ec, "add");
impl_.get_service().add(impl_.get_implementation(), signal_number_3, ec);
boost::asio::detail::throw_error(ec, "add");
}
/// Construct a signal set and add three signals.
/**
* This constructor creates a signal set and registers for three signals.
*
* @param context An execution context which provides the I/O executor that
* the signal set will use, by default, to dispatch handlers for any
* asynchronous operations performed on the signal set.
*
* @param signal_number_1 The first signal number to be added.
*
* @param signal_number_2 The second signal number to be added.
*
* @param signal_number_3 The third signal number to be added.
*
* @note This constructor is equivalent to performing:
* @code boost::asio::signal_set signals(context);
* signals.add(signal_number_1);
* signals.add(signal_number_2);
* signals.add(signal_number_3); @endcode
*/
template
basic_signal_set(ExecutionContext& context, int signal_number_1,
int signal_number_2, int signal_number_3,
typename enable_if<
is_convertible::value
>::type* = 0)
: impl_(context)
{
boost::system::error_code ec;
impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
boost::asio::detail::throw_error(ec, "add");
impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
boost::asio::detail::throw_error(ec, "add");
impl_.get_service().add(impl_.get_implementation(), signal_number_3, ec);
boost::asio::detail::throw_error(ec, "add");
}
/// Destroys the signal set.
/**
* This function destroys the signal set, cancelling any outstanding
* asynchronous wait operations associated with the signal set as if by
* calling @c cancel.
*/
~basic_signal_set()
{
}
/// Get the executor associated with the object.
executor_type get_executor() BOOST_ASIO_NOEXCEPT
{
return impl_.get_executor();
}
/// Add a signal to a signal_set.
/**
* This function adds the specified signal to the set. It has no effect if the
* signal is already in the set.
*
* @param signal_number The signal to be added to the set.
*
* @throws boost::system::system_error Thrown on failure.
*/
void add(int signal_number)
{
boost::system::error_code ec;
impl_.get_service().add(impl_.get_implementation(), signal_number, ec);
boost::asio::detail::throw_error(ec, "add");
}
/// Add a signal to a signal_set.
/**
* This function adds the specified signal to the set. It has no effect if the
* signal is already in the set.
*
* @param signal_number The signal to be added to the set.
*
* @param ec Set to indicate what error occurred, if any.
*/
BOOST_ASIO_SYNC_OP_VOID add(int signal_number,
boost::system::error_code& ec)
{
impl_.get_service().add(impl_.get_implementation(), signal_number, ec);
BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
}
/// Remove a signal from a signal_set.
/**
* This function removes the specified signal from the set. It has no effect
* if the signal is not in the set.
*
* @param signal_number The signal to be removed from the set.
*
* @throws boost::system::system_error Thrown on failure.
*
* @note Removes any notifications that have been queued for the specified
* signal number.
*/
void remove(int signal_number)
{
boost::system::error_code ec;
impl_.get_service().remove(impl_.get_implementation(), signal_number, ec);
boost::asio::detail::throw_error(ec, "remove");
}
/// Remove a signal from a signal_set.
/**
* This function removes the specified signal from the set. It has no effect
* if the signal is not in the set.
*
* @param signal_number The signal to be removed from the set.
*
* @param ec Set to indicate what error occurred, if any.
*
* @note Removes any notifications that have been queued for the specified
* signal number.
*/
BOOST_ASIO_SYNC_OP_VOID remove(int signal_number,
boost::system::error_code& ec)
{
impl_.get_service().remove(impl_.get_implementation(), signal_number, ec);
BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
}
/// Remove all signals from a signal_set.
/**
* This function removes all signals from the set. It has no effect if the set
* is already empty.
*
* @throws boost::system::system_error Thrown on failure.
*
* @note Removes all queued notifications.
*/
void clear()
{
boost::system::error_code ec;
impl_.get_service().clear(impl_.get_implementation(), ec);
boost::asio::detail::throw_error(ec, "clear");
}
/// Remove all signals from a signal_set.
/**
* This function removes all signals from the set. It has no effect if the set
* is already empty.
*
* @param ec Set to indicate what error occurred, if any.
*
* @note Removes all queued notifications.
*/
BOOST_ASIO_SYNC_OP_VOID clear(boost::system::error_code& ec)
{
impl_.get_service().clear(impl_.get_implementation(), ec);
BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
}
/// Cancel all operations associated with the signal set.
/**
* This function forces the completion of any pending asynchronous wait
* operations against the signal set. The handler for each cancelled
* operation will be invoked with the boost::asio::error::operation_aborted
* error code.
*
* Cancellation does not alter the set of registered signals.
*
* @throws boost::system::system_error Thrown on failure.
*
* @note If a registered signal occurred before cancel() is called, then the
* handlers for asynchronous wait operations will:
*
* @li have already been invoked; or
*
* @li have been queued for invocation in the near future.
*
* These handlers can no longer be cancelled, and therefore are passed an
* error code that indicates the successful completion of the wait operation.
*/
void cancel()
{
boost::system::error_code ec;
impl_.get_service().cancel(impl_.get_implementation(), ec);
boost::asio::detail::throw_error(ec, "cancel");
}
/// Cancel all operations associated with the signal set.
/**
* This function forces the completion of any pending asynchronous wait
* operations against the signal set. The handler for each cancelled
* operation will be invoked with the boost::asio::error::operation_aborted
* error code.
*
* Cancellation does not alter the set of registered signals.
*
* @param ec Set to indicate what error occurred, if any.
*
* @note If a registered signal occurred before cancel() is called, then the
* handlers for asynchronous wait operations will:
*
* @li have already been invoked; or
*
* @li have been queued for invocation in the near future.
*
* These handlers can no longer be cancelled, and therefore are passed an
* error code that indicates the successful completion of the wait operation.
*/
BOOST_ASIO_SYNC_OP_VOID cancel(boost::system::error_code& ec)
{
impl_.get_service().cancel(impl_.get_implementation(), ec);
BOOST_ASIO_SYNC_OP_VOID_RETURN(ec);
}
/// Start an asynchronous operation to wait for a signal to be delivered.
/**
* This function may be used to initiate an asynchronous wait against the
* signal set. It always returns immediately.
*
* For each call to async_wait(), the supplied handler will be called exactly
* once. The handler will be called when:
*
* @li One of the registered signals in the signal set occurs; or
*
* @li The signal set was cancelled, in which case the handler is passed the
* error code boost::asio::error::operation_aborted.
*
* @param handler The handler to be called when the signal occurs. Copies
* will be made of the handler as required. The function signature of the
* handler must be:
* @code void handler(
* const boost::system::error_code& error, // Result of operation.
* int signal_number // Indicates which signal occurred.
* ); @endcode
* Regardless of whether the asynchronous operation completes immediately or
* not, the handler will not be invoked from within this function. On
* immediate completion, invocation of the handler will be performed in a
* manner equivalent to using boost::asio::post().
*/
template <
BOOST_ASIO_COMPLETION_TOKEN_FOR(void (boost::system::error_code, int))
SignalHandler BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(SignalHandler,
void (boost::system::error_code, int))
async_wait(
BOOST_ASIO_MOVE_ARG(SignalHandler) handler
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
{
return async_initiate(
initiate_async_wait(this), handler);
}
private:
// Disallow copying and assignment.
basic_signal_set(const basic_signal_set&) BOOST_ASIO_DELETED;
basic_signal_set& operator=(const basic_signal_set&) BOOST_ASIO_DELETED;
class initiate_async_wait
{
public:
typedef Executor executor_type;
explicit initiate_async_wait(basic_signal_set* self)
: self_(self)
{
}
executor_type get_executor() const BOOST_ASIO_NOEXCEPT
{
return self_->get_executor();
}
template
void operator()(BOOST_ASIO_MOVE_ARG(SignalHandler) handler) const
{
// If you get an error on the following line it means that your handler
// does not meet the documented type requirements for a SignalHandler.
BOOST_ASIO_SIGNAL_HANDLER_CHECK(SignalHandler, handler) type_check;
detail::non_const_lvalue handler2(handler);
self_->impl_.get_service().async_wait(
self_->impl_.get_implementation(),
handler2.value, self_->impl_.get_executor());
}
private:
basic_signal_set* self_;
};
detail::io_object_impl impl_;
};
} // namespace asio
} // namespace boost
#endif // BOOST_ASIO_BASIC_SIGNAL_SET_HPP