libcarla/include/system/boost/process/v2/posix/vfork_launcher.hpp
2024-10-18 13:19:59 +08:00

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5.2 KiB
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// Copyright (c) 2022 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)
#ifndef BOOST_PROCESS_V2_POSIX_VFORK_LAUNCHER_HPP
#define BOOST_PROCESS_V2_POSIX_VFORK_LAUNCHER_HPP
#include <boost/process/v2/posix/default_launcher.hpp>
#include <unistd.h>
BOOST_PROCESS_V2_BEGIN_NAMESPACE
namespace posix
{
/// A launcher using vfork instead of fork.
struct vfork_launcher : default_launcher
{
vfork_launcher() = default;
template<typename ExecutionContext, typename Args, typename ... Inits>
auto operator()(ExecutionContext & context,
const typename std::enable_if<std::is_convertible<
ExecutionContext&, BOOST_PROCESS_V2_ASIO_NAMESPACE::execution_context&>::value,
filesystem::path >::type & executable,
Args && args,
Inits && ... inits ) -> basic_process<typename ExecutionContext::executor_type>
{
error_code ec;
auto proc = (*this)(context, ec, executable, std::forward<Args>(args), std::forward<Inits>(inits)...);
if (ec)
asio::detail::throw_error(ec, "default_launcher");
return proc;
}
template<typename ExecutionContext, typename Args, typename ... Inits>
auto operator()(ExecutionContext & context,
error_code & ec,
const typename std::enable_if<std::is_convertible<
ExecutionContext&, BOOST_PROCESS_V2_ASIO_NAMESPACE::execution_context&>::value,
filesystem::path >::type & executable,
Args && args,
Inits && ... inits ) -> basic_process<typename ExecutionContext::executor_type>
{
return (*this)(context.get_executor(), executable, std::forward<Args>(args), std::forward<Inits>(inits)...);
}
template<typename Executor, typename Args, typename ... Inits>
auto operator()(Executor exec,
const typename std::enable_if<
BOOST_PROCESS_V2_ASIO_NAMESPACE::execution::is_executor<Executor>::value ||
BOOST_PROCESS_V2_ASIO_NAMESPACE::is_executor<Executor>::value,
filesystem::path >::type & executable,
Args && args,
Inits && ... inits ) -> basic_process<Executor>
{
error_code ec;
auto proc = (*this)(std::move(exec), ec, executable, std::forward<Args>(args), std::forward<Inits>(inits)...);
if (ec)
asio::detail::throw_error(ec, "default_launcher");
return proc;
}
template<typename Executor, typename Args, typename ... Inits>
auto operator()(Executor exec,
error_code & ec,
const typename std::enable_if<
BOOST_PROCESS_V2_ASIO_NAMESPACE::execution::is_executor<Executor>::value ||
BOOST_PROCESS_V2_ASIO_NAMESPACE::is_executor<Executor>::value,
filesystem::path >::type & executable,
Args && args,
Inits && ... inits ) -> basic_process<Executor>
{
auto argv = this->build_argv_(executable, std::forward<Args>(args));
ec = detail::on_setup(*this, executable, argv, inits ...);
if (ec)
{
detail::on_error(*this, executable, argv, ec, inits...);
return basic_process<Executor>(exec);
}
auto & ctx = BOOST_PROCESS_V2_ASIO_NAMESPACE::query(
exec, BOOST_PROCESS_V2_ASIO_NAMESPACE::execution::context);
ctx.notify_fork(BOOST_PROCESS_V2_ASIO_NAMESPACE::execution_context::fork_prepare);
pid = ::vfork();
if (pid == -1)
{
ctx.notify_fork(BOOST_PROCESS_V2_ASIO_NAMESPACE::execution_context::fork_parent);
detail::on_fork_error(*this, executable, argv, ec, inits...);
detail::on_error(*this, executable, argv, ec, inits...);
ec.assign(errno, system_category());
return basic_process<Executor>{exec};
}
else if (pid == 0)
{
ctx.notify_fork(BOOST_PROCESS_V2_ASIO_NAMESPACE::execution_context::fork_child);
ec = detail::on_exec_setup(*this, executable, argv, inits...);
if (!ec)
close_all_fds(ec);
if (!ec)
::execve(executable.c_str(), const_cast<char * const *>(argv), const_cast<char * const *>(env));
ec.assign(errno, system_category());
detail::on_exec_error(*this, executable, argv, ec, inits...);
::exit(EXIT_FAILURE);
return basic_process<Executor>{exec};
}
ctx.notify_fork(BOOST_PROCESS_V2_ASIO_NAMESPACE::execution_context::fork_parent);
if (ec)
{
detail::on_error(*this, executable, argv, ec, inits...);
return basic_process<Executor>{exec};
}
basic_process<Executor> proc(exec, pid);
detail::on_success(*this, executable, argv, ec, inits...);
return proc;
}
};
}
BOOST_PROCESS_V2_END_NAMESPACE
#endif //BOOST_PROCESS_V2_POSIX_VFORK_LAUNCHER_HPP