boost/process/detail/windows/compare_handles.hpp

   1 // Copyright (c) 2016 Klemens D. Morgenstern
   2 //
   3 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef BOOST_PROCESS_DETAIL_WINDOWS_COMPARE_HANDLES_HPP_
   7 #define BOOST_PROCESS_DETAIL_WINDOWS_COMPARE_HANDLES_HPP_
   8
   9 #include <boost/detail/winapi/handles.hpp>
  10 #include <boost/detail/winapi/file_management.hpp>
  11 #include <boost/process/detail/config.hpp>
  12
  13 namespace boost { namespace process { namespace detail { namespace windows {
  14
  15 inline bool compare_handles(boost::detail::winapi::HANDLE_ lhs, boost::detail::winapi::HANDLE_ rhs)
  16 {
  17     if ( (lhs == ::boost::detail::winapi::INVALID_HANDLE_VALUE_)
  18       || (rhs == ::boost::detail::winapi::INVALID_HANDLE_VALUE_))
  19         return false;
  20
  21     if (lhs == rhs)
  22         return true;
  23
  24     ::boost::detail::winapi::BY_HANDLE_FILE_INFORMATION_ lhs_info{0,{0,0},{0,0},{0,0},0,0,0,0,0,0};
  25     ::boost::detail::winapi::BY_HANDLE_FILE_INFORMATION_ rhs_info{0,{0,0},{0,0},{0,0},0,0,0,0,0,0};
  26
  27     if (!::boost::detail::winapi::GetFileInformationByHandle(lhs, &lhs_info))
  28         ::boost::process::detail::throw_last_error("GetFileInformationByHandle");
  29
  30     if (!::boost::detail::winapi::GetFileInformationByHandle(rhs, &rhs_info))
  31         ::boost::process::detail::throw_last_error("GetFileInformationByHandle");
  32
  33     return     (lhs_info.nFileIndexHigh == rhs_info.nFileIndexHigh)
  34             && (lhs_info.nFileIndexLow  == rhs_info.nFileIndexLow);
  35 }
  36
  37 }}}}
  38
  39
  40
  41 #endif /* BOOST_PROCESS_DETAIL_WINDOWS_COMPARE_HANDLES_HPP_ */