detail/posix/file_out.hpp

0001 // Copyright (c) 2006, 2007 Julio M. Merino Vidal
0002 // Copyright (c) 2008 Ilya Sokolov, Boris Schaeling
0003 // Copyright (c) 2009 Boris Schaeling
0004 // Copyright (c) 2010 Felipe Tanus, Boris Schaeling
0005 // Copyright (c) 2011, 2012 Jeff Flinn, Boris Schaeling
0006 // Copyright (c) 2016 Klemens D. Morgenstern
0007 //
0008 // Distributed under the Boost Software License, Version 1.0. (See accompanying
0009 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0010
0011 #ifndef BOOST_PROCESS_POSIX_FILE_OUT_HPP
0012 #define BOOST_PROCESS_POSIX_FILE_OUT_HPP
0013
0014 #include <boost/process/detail/posix/handler.hpp>
0015 #include <boost/process/detail/posix/file_descriptor.hpp>
0016 #include <boost/process/detail/used_handles.hpp>
0017 #include <unistd.h>
0018
0019 namespace boost { namespace process { namespace detail { namespace posix {
0020
0021 template<int p1, int p2>
0022 struct file_out : handler_base_ext, ::boost::process::detail::uses_handles
0023 {
0024     file_descriptor file;
0025     int handle = file.handle();
0026
0027     template<typename T>
0028     file_out(T&& t) : file(std::forward<T>(t), file_descriptor::write), handle(file.handle()) {}
0029     file_out(FILE * f) : handle(fileno(f)) {}
0030
0031     std::array<int, 3> get_used_handles()
0032     {
0033         const auto pp1 = p1 != -1 ? p1 : p2;
0034         const auto pp2 = p2 != -1 ? p2 : p1;
0035
0036         return {handle, pp1, pp2};
0037     }
0038
0039     template <typename Executor>
0040     void on_exec_setup(Executor &e) const;
0041 };
0042
0043 template<>
0044 template<typename Executor>
0045 void file_out<1,-1>::on_exec_setup(Executor &e) const
0046 {
0047     if (::dup2(handle, STDOUT_FILENO) == -1)
0048          e.set_error(::boost::process::detail::get_last_error(), "dup2() failed");
0049 }
0050
0051 template<>
0052 template<typename Executor>
0053 void file_out<2,-1>::on_exec_setup(Executor &e) const
0054 {
0055     if (::dup2(handle, STDERR_FILENO) == -1)
0056          e.set_error(::boost::process::detail::get_last_error(), "dup2() failed");
0057 }
0058
0059 template<>
0060 template<typename Executor>
0061 void file_out<1,2>::on_exec_setup(Executor &e) const
0062 {
0063     if (::dup2(handle, STDOUT_FILENO) == -1)
0064          e.set_error(::boost::process::detail::get_last_error(), "dup2() failed");
0065
0066     if (::dup2(handle, STDERR_FILENO) == -1)
0067          e.set_error(::boost::process::detail::get_last_error(), "dup2() failed");
0068
0069 }
0070
0071 }}}}
0072
0073 #endif