ceph/src/boost/boost/asio/detail/impl/pipe_select_interrupter.ipp

   1 //
   2 // detail/impl/pipe_select_interrupter.ipp
   3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2017 Christopher M. Kohlhoff (chris at kohlhoff dot com)
   6 //
   7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9 //
  10
  11 #ifndef BOOST_ASIO_DETAIL_IMPL_PIPE_SELECT_INTERRUPTER_IPP
  12 #define BOOST_ASIO_DETAIL_IMPL_PIPE_SELECT_INTERRUPTER_IPP
  13
  14 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  15 # pragma once
  16 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  17
  18 #include <boost/asio/detail/config.hpp>
  19
  20 #if !defined(BOOST_ASIO_WINDOWS_RUNTIME)
  21 #if !defined(BOOST_ASIO_WINDOWS)
  22 #if !defined(__CYGWIN__)
  23 #if !defined(__SYMBIAN32__)
  24 #if !defined(BOOST_ASIO_HAS_EVENTFD)
  25
  26 #include <fcntl.h>
  27 #include <sys/stat.h>
  28 #include <sys/types.h>
  29 #include <unistd.h>
  30 #include <boost/asio/detail/pipe_select_interrupter.hpp>
  31 #include <boost/asio/detail/socket_types.hpp>
  32 #include <boost/asio/detail/throw_error.hpp>
  33 #include <boost/asio/error.hpp>
  34
  35 #include <boost/asio/detail/push_options.hpp>
  36
  37 namespace boost {
  38 namespace asio {
  39 namespace detail {
  40
  41 pipe_select_interrupter::pipe_select_interrupter()
  42 {
  43   open_descriptors();
  44 }
  45
  46 void pipe_select_interrupter::open_descriptors()
  47 {
  48   int pipe_fds[2];
  49   if (pipe(pipe_fds) == 0)
  50   {
  51     read_descriptor_ = pipe_fds[0];
  52     ::fcntl(read_descriptor_, F_SETFL, O_NONBLOCK);
  53     write_descriptor_ = pipe_fds[1];
  54     ::fcntl(write_descriptor_, F_SETFL, O_NONBLOCK);
  55
  56 #if defined(FD_CLOEXEC)
  57     ::fcntl(read_descriptor_, F_SETFD, FD_CLOEXEC);
  58     ::fcntl(write_descriptor_, F_SETFD, FD_CLOEXEC);
  59 #endif // defined(FD_CLOEXEC)
  60   }
  61   else
  62   {
  63     boost::system::error_code ec(errno,
  64         boost::asio::error::get_system_category());
  65     boost::asio::detail::throw_error(ec, "pipe_select_interrupter");
  66   }
  67 }
  68
  69 pipe_select_interrupter::~pipe_select_interrupter()
  70 {
  71   close_descriptors();
  72 }
  73
  74 void pipe_select_interrupter::close_descriptors()
  75 {
  76   if (read_descriptor_ != -1)
  77     ::close(read_descriptor_);
  78   if (write_descriptor_ != -1)
  79     ::close(write_descriptor_);
  80 }
  81
  82 void pipe_select_interrupter::recreate()
  83 {
  84   close_descriptors();
  85
  86   write_descriptor_ = -1;
  87   read_descriptor_ = -1;
  88
  89   open_descriptors();
  90 }
  91
  92 void pipe_select_interrupter::interrupt()
  93 {
  94   char byte = 0;
  95   signed_size_type result = ::write(write_descriptor_, &byte, 1);
  96   (void)result;
  97 }
  98
  99 bool pipe_select_interrupter::reset()
 100 {
 101   for (;;)
 102   {
 103     char data[1024];
 104     signed_size_type bytes_read = ::read(read_descriptor_, data, sizeof(data));
 105     if (bytes_read < 0 && errno == EINTR)
 106       continue;
 107     bool was_interrupted = (bytes_read > 0);
 108     while (bytes_read == sizeof(data))
 109       bytes_read = ::read(read_descriptor_, data, sizeof(data));
 110     return was_interrupted;
 111   }
 112 }
 113
 114 } // namespace detail
 115 } // namespace asio
 116 } // namespace boost
 117
 118 #include <boost/asio/detail/pop_options.hpp>
 119
 120 #endif // !defined(BOOST_ASIO_HAS_EVENTFD)
 121 #endif // !defined(__SYMBIAN32__)
 122 #endif // !defined(__CYGWIN__)
 123 #endif // !defined(BOOST_ASIO_WINDOWS)
 124 #endif // !defined(BOOST_ASIO_WINDOWS_RUNTIME)
 125
 126 #endif // BOOST_ASIO_DETAIL_IMPL_PIPE_SELECT_INTERRUPTER_IPP