// 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_ */
|
