ceph/src/boost/libs/fiber/include/boost/fiber/operations.hpp

   1 //          Copyright Oliver Kowalke 2013.
   2 // Distributed under the Boost Software License, Version 1.0.
   3 //    (See accompanying file LICENSE_1_0.txt or copy at
   4 //          http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef BOOST_THIS_FIBER_OPERATIONS_H
   7 #define BOOST_THIS_FIBER_OPERATIONS_H
   8
   9 #include <chrono>
  10
  11 #include <boost/config.hpp>
  12
  13 #include <boost/fiber/context.hpp>
  14 #include <boost/fiber/detail/config.hpp>
  15 #include <boost/fiber/detail/convert.hpp>
  16 #include <boost/fiber/fiber.hpp>
  17 #include <boost/fiber/scheduler.hpp>
  18
  19 #ifdef BOOST_HAS_ABI_HEADERS
  20 #  include BOOST_ABI_PREFIX
  21 #endif
  22
  23 namespace boost {
  24 namespace this_fiber {
  25
  26 inline
  27 fibers::fiber::id get_id() noexcept {
  28     return fibers::context::active()->get_id();
  29 }
  30
  31 inline
  32 void yield() noexcept {
  33     fibers::context::active()->yield();
  34 }
  35
  36 template< typename Clock, typename Duration >
  37 void sleep_until( std::chrono::time_point< Clock, Duration > const& sleep_time_) {
  38     std::chrono::steady_clock::time_point sleep_time(
  39             boost::fibers::detail::convert( sleep_time_) );
  40     fibers::context::active()->wait_until( sleep_time);
  41 }
  42
  43 template< typename Rep, typename Period >
  44 void sleep_for( std::chrono::duration< Rep, Period > const& timeout_duration) {
  45     fibers::context::active()->wait_until(
  46             std::chrono::steady_clock::now() + timeout_duration);
  47 }
  48
  49 template< typename PROPS >
  50 PROPS & properties() {
  51     fibers::fiber_properties * props =
  52         fibers::context::active()->get_properties();
  53     if ( ! props) {
  54         // props could be nullptr if the thread's main fiber has not yet
  55         // yielded (not yet passed through algorithm_with_properties::
  56         // awakened()). Address that by yielding right now.
  57         yield();
  58         // Try again to obtain the fiber_properties subclass instance ptr.
  59         // Walk through the whole chain again because who knows WHAT might
  60         // have happened while we were yielding!
  61         props = fibers::context::active()->get_properties();
  62         // Could still be hosed if the running manager isn't a subclass of
  63         // algorithm_with_properties.
  64         BOOST_ASSERT_MSG(props, "this_fiber::properties not set");
  65     }
  66     return dynamic_cast< PROPS & >( * props );
  67 }
  68
  69 }
  70
  71 namespace fibers {
  72
  73 inline
  74 bool has_ready_fibers() noexcept {
  75     return boost::fibers::context::active()->get_scheduler()->has_ready_fibers();
  76 }
  77
  78 template< typename SchedAlgo, typename ... Args >
  79 void use_scheduling_algorithm( Args && ... args) noexcept {
  80     boost::fibers::context::active()->get_scheduler()
  81         ->set_algo(
  82             std::unique_ptr< SchedAlgo >(
  83                 new SchedAlgo( std::forward< Args >( args) ... ) ) );
  84 }
  85
  86 }}
  87
  88 #ifdef BOOST_HAS_ABI_HEADERS
  89 #  include BOOST_ABI_SUFFIX
  90 #endif
  91
  92 #endif // BOOST_THIS_FIBER_OPERATIONS_H