added BOOST_PROCESS_V2_DISABLE_SIGNALSET option

include/boost/process/v2/default_launcher.hpp

@@ -18,6 +18,8 @@
 #else
 #if defined(BOOST_PROCESS_V2_PDFORK)
 #include <boost/process/v2/posix/pdfork_launcher.hpp>
+#elif defined(BOOST_PROCESS_V2_PIPEFORK)
+#include <boost/process/v2/posix/pipe_fork_launcher.hpp>
 #else
 #include <boost/process/v2/posix/default_launcher.hpp>
 #endif
@@ -48,6 +50,8 @@ typedef windows::default_launcher default_process_launcher;
 #else
 #if defined(BOOST_PROCESS_V2_PDFORK)
 typedef posix::pdfork_launcher default_process_launcher;
+#elif defined(BOOST_PROCESS_V2_PIPEFORK)
+typedef posix::pipe_fork_launcher default_process_launcher;
 #else
 typedef posix::default_launcher default_process_launcher;
 #endif

include/boost/process/v2/detail/config.hpp

@@ -165,7 +165,7 @@ BOOST_PROCESS_V2_END_NAMESPACE
 
 #include <sys/syscall.h>
 
-#if defined(SYS_pidfd_open)
+#if defined(SYS_pidfd_open) && !defined(BOOST_PROCESS_V2_DISABLE_PIDFD_OPEN)
 #define BOOST_PROCESS_V2_PIDFD_OPEN 1
 #define BOOST_PROCESS_V2_HAS_PROCESS_HANDLE 1
 #endif

include/boost/process/v2/detail/process_handle_fd.hpp

@@ -255,7 +255,7 @@ struct basic_process_handle_fd
             ec.clear();
             exit_code = code;
         }
-      return false;
+        return false;
     }
 
     bool running(native_exit_code_type &exit_code)

include/boost/process/v2/detail/process_handle_fd_or_signal.hpp

@@ -18,19 +18,27 @@
 
 #if defined(BOOST_PROCESS_V2_STANDALONE)
 #include <asio/any_io_executor.hpp>
+#include <asio/append.hpp>
+#include <asio/associated_immediate_executor.hpp>
 #include <asio/compose.hpp>
 #include <asio/dispatch.hpp>
 #include <asio/posix/basic_stream_descriptor.hpp>
 #include <asio/post.hpp>
-#include <asio/windows/signal_set.hpp>
+#if !defined(BOOST_PROCESS_V2_DISABLE_SIGNALSET)
+#include <asio/signal_set.hpp>
+#endif
 #else
 #include <boost/asio/any_io_executor.hpp>
+#include <boost/asio/append.hpp>
+#include <boost/asio/associated_immediate_executor.hpp>
 #include <boost/asio/compose.hpp>
 #include <boost/asio/dispatch.hpp>
 #include <boost/asio/posix/basic_stream_descriptor.hpp>
 #include <boost/asio/post.hpp>
+#if !defined(BOOST_PROCESS_V2_DISABLE_SIGNALSET)
 #include <boost/asio/signal_set.hpp>
 #endif
+#endif
 
 BOOST_PROCESS_V2_BEGIN_NAMESPACE
 
@@ -45,7 +53,7 @@ struct basic_process_handle_fd_or_signal
     typedef Executor executor_type;
 
     executor_type get_executor()
-    { return signal_set_.get_executor(); }
+    { return descriptor_.get_executor(); }
 
     /// Rebinds the process_handle to another executor.
     template<typename Executor1>
@@ -277,14 +285,13 @@ struct basic_process_handle_fd_or_signal
         int res = ::waitpid(pid_, &code, WNOHANG);
         if (res == -1)
             ec = get_last_error();
-        else
-            ec.clear();
-
-        if (process_is_running(res))
+        else if (res == 0)
             return true;
         else
+        {
+            ec.clear();
             exit_code = code;
-
+        }
         return false;
     }
 
@@ -311,12 +318,19 @@ struct basic_process_handle_fd_or_signal
     struct basic_process_handle_fd_or_signal;
     pid_type pid_ = -1;
     net::posix::basic_stream_descriptor<Executor> descriptor_;
+#if !defined(BOOST_PROCESS_V2_DISABLE_SIGNALSET)
     net::basic_signal_set<Executor> signal_set_{descriptor_.get_executor(), SIGCHLD};
-
+#else
+    int signal_set_;
+#endif
     struct async_wait_op_
     {
         net::posix::basic_descriptor<Executor> &descriptor;
+#if !defined(BOOST_PROCESS_V2_DISABLE_SIGNALSET)
         net::basic_signal_set<Executor> &handle;
+#else
+        int dummy;
+#endif
         pid_type pid_;
         bool needs_post = true;
 
@@ -343,35 +357,41 @@ struct basic_process_handle_fd_or_signal
 
             if (!ec && (wait_res == 0))
             {
-                needs_post = false;
                 if (descriptor.is_open())
-                    descriptor.async_wait(
-                            net::posix::descriptor_base::wait_read,
-                            std::move(self));
+                {
+                  needs_post = false;
+                  descriptor.async_wait(
+                      net::posix::descriptor_base::wait_read,
+                      std::move(self));
+                  return;
+                }
                 else
-                    handle.async_wait(std::move(self));
-                return;
+                {
+#if !defined(BOOST_PROCESS_V2_DISABLE_SIGNALSET)
+                  needs_post = false;
+                  handle.async_wait(std::move(self));
+                  return;
+#else
+                  BOOST_PROCESS_V2_ASSIGN_EC(ec, net::error::operation_not_supported);
+#endif
+                }
             }
 
-            struct completer
-            {
-                error_code ec;
-                native_exit_code_type code;
-                typename std::decay<Self>::type self;
-
-                void operator()()
-                {
-                    self.complete(ec, code);
-                }
-            };
-
-            const auto exec = self.get_executor();
-            completer cpl{ec, exit_code, std::move(self)};
             if (needs_post)
-                net::post(exec, std::move(cpl));
+            {
+              auto exec = net::get_associated_immediate_executor(self, descriptor.get_executor());
+              net::dispatch(exec, net::append(std::move(self), exit_code, ec));
+            }
             else
-                net::dispatch(exec, std::move(cpl));
-
+            {
+              auto exec = net::get_associated_executor(self);
+              net::dispatch(exec, net::append(std::move(self), exit_code, ec));
+            }
+        }
+        template<typename Self>
+        void operator()(Self &&self, native_exit_code_type code, error_code ec)
+        {
+          self.complete(ec, code);
         }
     };
  public:

include/boost/process/v2/detail/process_handle_signal.hpp

@@ -17,17 +17,25 @@
 
 #if defined(BOOST_PROCESS_V2_STANDALONE)
 #include <asio/any_io_executor.hpp>
+#include <asio/append.hpp>
+#include <asio/associated_immediate_executor.hpp>
 #include <asio/compose.hpp>
 #include <asio/dispatch.hpp>
 #include <asio/post.hpp>
+#if !defined(BOOST_PROCESS_V2_DISABLE_SIGNALSET)
 #include <asio/signal_set.hpp>
+#endif
 #else
 #include <boost/asio/any_io_executor.hpp>
+#include <boost/asio/append.hpp>
+#include <boost/asio/associated_immediate_executor.hpp>
 #include <boost/asio/compose.hpp>
 #include <boost/asio/dispatch.hpp>
 #include <boost/asio/post.hpp>
+#if !defined(BOOST_PROCESS_V2_DISABLE_SIGNALSET)
 #include <boost/asio/signal_set.hpp>
 #endif
+#endif
 
 BOOST_PROCESS_V2_BEGIN_NAMESPACE
 
@@ -86,9 +94,14 @@ struct basic_process_handle_signal
     basic_process_handle_signal& operator=(basic_process_handle_signal && handle)
     {
         pid_ = handle.id();
+#if !defined(BOOST_PROCESS_V2_DISABLE_SIGNALSET)
+
         signal_set_.~basic_signal_set();
         using ss = net::basic_signal_set<Executor>;
         new (&signal_set_) ss(handle.get_executor(), SIGCHLD);
+#else
+        signal_set_.executor = handle.signal_set_.executor;
+#endif
         handle.pid_ = -1;
         return *this;
     }
@@ -244,11 +257,13 @@ struct basic_process_handle_signal
         int res = ::waitpid(pid_, &code, WNOHANG);
         if (res == -1)
             ec = get_last_error();
-        
-        if (res == 0)
+        else if (res == 0)
             return true;
         else
+        {
+            ec.clear();
             exit_code = code;
+        }
         return false;
     }
 
@@ -273,10 +288,24 @@ struct basic_process_handle_signal
     template<typename>
     friend struct basic_process_handle_signal;
     pid_type pid_ = -1;
+#if !defined(BOOST_PROCESS_V2_DISABLE_SIGNALSET)
     net::basic_signal_set<Executor> signal_set_;
-
+#else
+    struct signal_set_dummy_
+    {
+      signal_set_dummy_(signal_set_dummy_ &&) = default;
+      signal_set_dummy_(const signal_set_dummy_ &) = default;
+      Executor executor;
+      using executor_type = Executor;
+      executor_type get_executor() {return executor;}
+      signal_set_dummy_(Executor executor, int) : executor(std::move(executor)) {}
+    };
+    signal_set_dummy_ signal_set_;
+#endif
     struct async_wait_op_
     {
+#if !defined(BOOST_PROCESS_V2_DISABLE_SIGNALSET)
+
         net::basic_signal_set<Executor> &handle;
         pid_type pid_;
         
@@ -315,20 +344,25 @@ struct basic_process_handle_signal
                 return;
             }
 
-            struct completer
-            {
-                error_code ec;
-                native_exit_code_type code;
-                typename std::decay<Self>::type self;
-
-                void operator()()
-                {
-                    self.complete(ec, code);
-                }
-            };
-
             const auto exec = self.get_executor();
-            net::dispatch(exec, completer{ec, exit_code, std::move(self)});
+            net::dispatch(exec, net::append(std::move(self), exit_code, ec));
+        }
+#else
+        signal_set_dummy_ dummy_;
+        pid_t pid;
+        template<typename Self>
+        void operator()(Self &&self)
+        {
+          auto exec = net::get_associated_immediate_executor(self, dummy_.get_executor());
+          error_code ec;
+          BOOST_PROCESS_V2_ASSIGN_EC(ec, net::error::operation_not_supported);
+          net::dispatch(exec, net::append(std::move(self), native_exit_code_type(), ec));
+        }
+#endif
+        template<typename Self>
+        void operator()(Self &&self, native_exit_code_type code, error_code ec)
+        {
+          self.complete(ec, code);
         }
     };
  public:

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

@@ -0,0 +1,185 @@
+// 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_PIPE_FORK_LAUNCHER_HPP
+#define BOOST_PROCESS_V2_POSIX_PIPE_FORK_LAUNCHER_HPP
+
+#include <boost/process/v2/posix/default_launcher.hpp>
+
+#include <unistd.h>
+
+BOOST_PROCESS_V2_BEGIN_NAMESPACE
+
+namespace posix
+{
+
+/// A launcher using `pipe_fork`. Default on FreeBSD
+struct pipe_fork_launcher : default_launcher
+{
+    /// The file descriptor of the subprocess. Set after fork.
+    pipe_fork_launcher() = default;
+
+    template<typename ExecutionContext, typename Args, typename ... Inits>
+    auto operator()(ExecutionContext & context,
+                    const typename std::enable_if<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, "pipe_fork_launcher");
+
+        return proc;
+    }
+
+
+    template<typename ExecutionContext, typename Args, typename ... Inits>
+    auto operator()(ExecutionContext & context,
+                    error_code & ec,
+                    const typename std::enable_if<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, "pipe_fork_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));
+        int fd = -1;
+        {
+            pipe_guard pg, pg_wait;
+            if (::pipe(pg.p))
+            {
+                BOOST_PROCESS_V2_ASSIGN_EC(ec, errno, system_category());
+                return basic_process<Executor>{exec};
+            }
+            if (::fcntl(pg.p[1], F_SETFD, FD_CLOEXEC))
+            {
+                BOOST_PROCESS_V2_ASSIGN_EC(ec, errno, system_category());
+                return basic_process<Executor>{exec};
+            }
+            if (::pipe(pg_wait.p))
+            {
+              BOOST_PROCESS_V2_ASSIGN_EC(ec, errno, system_category());
+              return basic_process<Executor>{exec};
+            }
+            if (::fcntl(pg_wait.p[1], F_SETFD, FD_CLOEXEC))
+            {
+                BOOST_PROCESS_V2_ASSIGN_EC(ec, errno, system_category());
+                return basic_process<Executor>{exec};
+            }
+            ec = detail::on_setup(*this, executable, argv, inits ...);
+            if (ec)
+            {
+                detail::on_error(*this, executable, argv, ec, inits...);
+                return basic_process<Executor>(exec);
+            }
+            fd_whitelist.push_back(pg.p[1]);
+            fd_whitelist.push_back(pg_wait.p[1]);
+
+            auto & ctx = net::query(
+                    exec, net::execution::context);
+            ctx.notify_fork(net::execution_context::fork_prepare);
+            pid = ::fork();
+            if (pid == -1)
+            {
+                ctx.notify_fork(net::execution_context::fork_parent);
+                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)
+            {
+                ctx.notify_fork(net::execution_context::fork_child);
+                ::close(pg.p[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));
+
+                default_launcher::ignore_unused(::write(pg.p[1], &errno, sizeof(int)));
+                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};
+            }
+            ctx.notify_fork(net::execution_context::fork_parent);
+            ::close(pg.p[1]);
+            pg.p[1] = -1;
+            ::close(pg_wait.p[1]);
+            pg_wait.p[1] = -1;
+            int child_error{0};
+            int count = -1;
+            while ((count = ::read(pg.p[0], &child_error, sizeof(child_error))) == -1)
+            {
+                int err = errno;
+                if ((err != EAGAIN) && (err != EINTR))
+                {
+                    BOOST_PROCESS_V2_ASSIGN_EC(ec, err, system_category());
+                    break;
+                }
+            }
+            if (count != 0)
+                BOOST_PROCESS_V2_ASSIGN_EC(ec, child_error, system_category());
+
+            if (ec)
+            {
+                detail::on_error(*this, executable, argv, ec, inits...);
+                return basic_process<Executor>{exec};
+            }
+            std::swap(fd, pg_wait.p[0]);
+        }
+
+        basic_process<Executor> proc(exec, pid, fd);
+        detail::on_success(*this, executable, argv, ec, inits...);
+        return proc;
+    }
+};
+
+
+}
+
+BOOST_PROCESS_V2_END_NAMESPACE
+
+
+#endif //BOOST_PROCESS_V2_POSIX_PIPE_FORK_LAUNCHER_HPP

include/boost/process/v2/process_handle.hpp

@@ -13,7 +13,7 @@
 
 #if defined(BOOST_PROCESS_V2_PIDFD_OPEN)
 #include <boost/process/v2/detail/process_handle_fd.hpp>
-#elif defined(BOOST_PROCESS_V2_PDFORK)
+#elif defined(BOOST_PROCESS_V2_PDFORK) || defined(BOOST_PROCESS_V2_PIPEFORK)
 #include <boost/process/v2/detail/process_handle_fd_or_signal.hpp>
 #else
 // with asio support we could use EVFILT_PROC:NOTE_EXIT as well.
@@ -107,9 +107,9 @@ struct basic_process_handle
     void request_exit()
 
     /// Unconditionally terminates the process and stores the exit code in exit_status.
-    void terminate(native_exit_code_type &exit_status, error_code &ec);\
+    void terminate(native_exit_code_type &exit_status, error_code &ec);
     /// Throwing @overload void terminate(native_exit_code_type &exit_code, error_code & ec)
-    void terminate(native_exit_code_type &exit_status);/
+    void terminate(native_exit_code_type &exit_status);
 
     /// Checks if the current process is running. 
     /**If it has already completed, it assigns the exit code to `exit_code`.
@@ -137,7 +137,7 @@ using basic_process_handle = detail::basic_process_handle_win<Executor>;
 #if defined(BOOST_PROCESS_V2_PIDFD_OPEN)
 template<typename Executor = net::any_io_executor>
 using basic_process_handle = detail::basic_process_handle_fd<Executor>;
-#elif defined(BOOST_PROCESS_V2_PDFORK) || defined(BOOST_PROCESS_V2_PIPE_LAUNCHER)
+#elif defined(BOOST_PROCESS_V2_PDFORK) || defined(BOOST_PROCESS_V2_PIPEFORK)
 template<typename Executor = net::any_io_executor>
 using basic_process_handle = detail::basic_process_handle_fd_or_signal<Executor>;
 #else

test/v2/ext.cpp

@@ -11,6 +11,7 @@
 #include <boost/process/v2/pid.hpp>
 #include <boost/process/v2/process.hpp>
 #include <boost/process/v2/start_dir.hpp>
+#include <boost/asio/io_context.hpp>
 #include <boost/test/unit_test.hpp>
 
 BOOST_AUTO_TEST_SUITE(ext)

test/v2/pid.cpp

@@ -7,6 +7,8 @@
 #include <boost/process/v2/pid.hpp>
 #include <boost/process/v2/process.hpp>
 
+#include <boost/asio/io_context.hpp>
+
 #include <boost/test/unit_test.hpp>
 
 #include <algorithm>

test/v2/process.cpp

@@ -655,7 +655,7 @@ BOOST_AUTO_TEST_CASE(async_cancel_wait)
   proc.async_wait(asio::cancel_after(std::chrono::milliseconds(100),
                          [&](boost::system::error_code ec, int)
                          {
-                           BOOST_CHECK(ec == asio::error::operation_aborted);
+                           BOOST_CHECK_EQUAL(ec, asio::error::operation_aborted);
                            BOOST_CHECK(proc.running());
                            if (proc.running())
                              proc.terminate();