| // Copyright (c) 2016 Klemens D. Morgenstern |
| // |
| // 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) |
| |
| /** \file boost/process/async.hpp |
| |
| The header which provides the basic asynchrounous features. |
| It provides the on_exit property, which allows callbacks when the process exits. |
| It also implements the necessary traits for passing an boost::asio::io_context, |
| which is needed for asynchronous communication. |
| |
| It also pulls the [boost::asio::buffer](http://www.boost.org/doc/libs/release/doc/html/boost_asio/reference/buffer.html) |
| into the boost::process namespace for convenience. |
| |
| \xmlonly |
| <programlisting> |
| namespace boost { |
| namespace process { |
| <emphasis>unspecified</emphasis> <ulink url="http://www.boost.org/doc/libs/1_61_0/doc/html/boost_asio/reference/buffer.html">buffer</ulink>; |
| <emphasis>unspecified</emphasis> <globalname alt="boost::process::on_exit">on_exit</globalname>; |
| } |
| } |
| </programlisting> |
| |
| \endxmlonly |
| */ |
| |
| #ifndef BOOST_PROCESS_ASYNC_HPP_ |
| #define BOOST_PROCESS_ASYNC_HPP_ |
| |
| #include <boost/process/detail/traits.hpp> |
| #include <boost/process/detail/on_exit.hpp> |
| |
| #include <boost/asio/io_context.hpp> |
| #include <boost/asio/streambuf.hpp> |
| #include <boost/asio/buffer.hpp> |
| #include <type_traits> |
| #include <boost/fusion/iterator/deref.hpp> |
| |
| #if defined(BOOST_POSIX_API) |
| #include <boost/process/detail/posix/io_context_ref.hpp> |
| #include <boost/process/detail/posix/async_in.hpp> |
| #include <boost/process/detail/posix/async_out.hpp> |
| #include <boost/process/detail/posix/on_exit.hpp> |
| |
| #elif defined(BOOST_WINDOWS_API) |
| #include <boost/process/detail/windows/io_context_ref.hpp> |
| #include <boost/process/detail/windows/async_in.hpp> |
| #include <boost/process/detail/windows/async_out.hpp> |
| #include <boost/process/detail/windows/on_exit.hpp> |
| #endif |
| |
| namespace boost { namespace process { namespace detail { |
| |
| struct async_tag; |
| |
| template<typename T> |
| struct is_io_context : std::false_type {}; |
| template<> |
| struct is_io_context<api::io_context_ref> : std::true_type {}; |
| |
| template<typename Tuple> |
| inline asio::io_context& get_io_context(const Tuple & tup) |
| { |
| auto& ref = *boost::fusion::find_if<is_io_context<boost::mpl::_>>(tup); |
| return ref.get(); |
| } |
| |
| struct async_builder |
| { |
| boost::asio::io_context * ios; |
| |
| void operator()(boost::asio::io_context & ios_) {this->ios = &ios_;}; |
| |
| typedef api::io_context_ref result_type; |
| api::io_context_ref get_initializer() {return api::io_context_ref (*ios);}; |
| }; |
| |
| |
| template<> |
| struct initializer_builder<async_tag> |
| { |
| typedef async_builder type; |
| }; |
| |
| } |
| |
| using ::boost::asio::buffer; |
| |
| |
| #if defined(BOOST_PROCESS_DOXYGEN) |
| /** When an io_context is passed, the on_exit property can be used, to be notified |
| when the child process exits. |
| |
| |
| The following syntax is valid |
| |
| \code{.cpp} |
| on_exit=function; |
| on_exit(function); |
| \endcode |
| |
| with `function` being a callable object with the signature `(int, const std::error_code&)` or an |
| `std::future<int>`. |
| |
| \par Example |
| |
| \code{.cpp} |
| io_context ios; |
| |
| child c("ls", ios, on_exit=[](int exit, const std::error_code& ec_in){}); |
| |
| std::future<int> exit_code; |
| chlid c2("ls", ios, on_exit=exit_code); |
| |
| \endcode |
| |
| \note The handler is not invoked when the launch fails. |
| \warning When used \ref ignore_error it might get invoked on error. |
| \warning `on_exit` uses `boost::asio::signal_set` to listen for `SIGCHLD` on posix, and so has the |
| same restrictions as that class (do not register a handler for `SIGCHLD` except by using |
| `boost::asio::signal_set`). |
| */ |
| constexpr static ::boost::process::detail::on_exit_ on_exit{}; |
| #endif |
| |
| }} |
| |
| |
| |
| #endif /* INCLUDE_BOOST_PROCESS_DETAIL_ASYNC_HPP_ */ |