整理

include/boost/process/v2/posix/vfork_launcher.hpp

@@ -0,0 +1,140 @@
+// 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&, net::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)
+            v2::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&, net::execution_context&>::value,
+                            filesystem::path >::type & executable,
+                    Args && args,
+                    Inits && ... inits ) -> basic_process<typename ExecutionContext::executor_type>
+    {
+        return (*this)(context.get_executor(), ec, 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<
+                            net::execution::is_executor<Executor>::value ||
+                            net::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)
+            v2::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<
+                            net::execution::is_executor<Executor>::value ||
+                            net::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 = net::query(exec, net::execution::context);
+#if !defined(BOOST_PROCESS_V2_DISABLE_NOTIFY_FORK)
+        ctx.notify_fork(net::execution_context::fork_prepare);
+#endif
+        pid = ::vfork();
+        if (pid == -1)
+        {
+#if !defined(BOOST_PROCESS_V2_DISABLE_NOTIFY_FORK)
+            ctx.notify_fork(net::execution_context::fork_parent);
+#endif
+            detail::on_fork_error(*this, executable, argv, ec, inits...);
+            detail::on_error(*this, executable, argv, ec, inits...);
+
+            BOOST_PROCESS_V2_ASSIGN_EC(ec, errno, system_category());
+            return basic_process<Executor>{exec};
+        }
+        else if (pid == 0)
+        {
+            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));
+
+            BOOST_PROCESS_V2_ASSIGN_EC(ec, errno, system_category());
+            detail::on_exec_error(*this, executable, argv, ec, inits...);
+            ::_exit(EXIT_FAILURE);
+            return basic_process<Executor>{exec};
+        }
+#if !defined(BOOST_PROCESS_V2_DISABLE_NOTIFY_FORK)
+        ctx.notify_fork(net::execution_context::fork_parent);
+#endif
+        if (ec)
+        {
+            detail::on_error(*this, executable, argv, ec, inits...);
+            do { ::waitpid(pid, nullptr, 0); } while (errno == EINTR);
+            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