TLA  Line data    Source code

       1                 : //
       2                 : // Copyright (c) 2026 Michael Vandeberg
       3                 : //
       4                 : // Distributed under the Boost Software License, Version 1.0. (See accompanying
       5                 : // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
       6                 : //
       7                 : // Official repository: https://github.com/cppalliance/corosio
       8                 : //
       9                 : 
      10                 : #ifndef BOOST_COROSIO_DETAIL_CONDITIONALLY_ENABLED_EVENT_HPP
      11                 : #define BOOST_COROSIO_DETAIL_CONDITIONALLY_ENABLED_EVENT_HPP
      12                 : 
      13                 : #include <boost/corosio/detail/conditionally_enabled_mutex.hpp>
      14                 : 
      15                 : #include <chrono>
      16                 : #include <condition_variable>
      17                 : 
      18                 : namespace boost::corosio::detail {
      19                 : 
      20                 : /* Condition variable wrapper that becomes a no-op when disabled.
      21                 : 
      22                 :    When enabled, notify/wait delegate to an underlying
      23                 :    std::condition_variable. When disabled, all operations
      24                 :    are no-ops. The wait paths are unreachable in
      25                 :    single-threaded mode because the task sentinel prevents
      26                 :    the empty-queue state in do_one().
      27                 : */
      28                 : class conditionally_enabled_event
      29                 : {
      30                 :     std::condition_variable cond_;
      31                 :     bool enabled_;
      32                 : 
      33                 : public:
      34 HIT        2118 :     explicit conditionally_enabled_event(bool enabled = true) noexcept
      35            2118 :         : enabled_(enabled)
      36                 :     {
      37            2118 :     }
      38                 : 
      39                 :     conditionally_enabled_event(conditionally_enabled_event const&) = delete;
      40                 :     conditionally_enabled_event&
      41                 :     operator=(conditionally_enabled_event const&) = delete;
      42                 : 
      43            2106 :     void set_enabled(bool v) noexcept
      44                 :     {
      45            2106 :         enabled_ = v;
      46            2106 :     }
      47                 : 
      48              44 :     void notify_one()
      49                 :     {
      50              44 :         if (enabled_)
      51              44 :             cond_.notify_one();
      52              44 :     }
      53                 : 
      54            3859 :     void notify_all()
      55                 :     {
      56            3859 :         if (enabled_)
      57            3847 :             cond_.notify_all();
      58            3859 :     }
      59                 : 
      60               9 :     void wait(conditionally_enabled_mutex::scoped_lock& lock)
      61                 :     {
      62               9 :         if (enabled_)
      63               9 :             cond_.wait(lock.underlying());
      64               9 :     }
      65                 : 
      66                 :     template<class Rep, class Period>
      67              31 :     void wait_for(
      68                 :         conditionally_enabled_mutex::scoped_lock& lock,
      69                 :         std::chrono::duration<Rep, Period> const& d)
      70                 :     {
      71              31 :         if (enabled_)
      72              31 :             cond_.wait_for(lock.underlying(), d);
      73              31 :     }
      74                 : };
      75                 : 
      76                 : } // namespace boost::corosio::detail
      77                 : 
      78                 : #endif // BOOST_COROSIO_DETAIL_CONDITIONALLY_ENABLED_EVENT_HPP