ceph/src/boost/libs/context/src/continuation.cpp

   1
   2 //          Copyright Oliver Kowalke 2017.
   3 // Distributed under the Boost Software License, Version 1.0.
   4 //    (See accompanying file LICENSE_1_0.txt or copy at
   5 //          http://www.boost.org/LICENSE_1_0.txt)
   6
   7 #if defined(BOOST_USE_UCONTEXT)
   8 #include "boost/context/continuation_ucontext.hpp"
   9 #elif defined(BOOST_USE_WINFIB)
  10 #include "boost/context/continuation_winfib.hpp"
  11 #else
  12 #include "boost/context/execution_context.hpp"
  13 #endif
  14
  15 #include <boost/config.hpp>
  16
  17 #ifdef BOOST_HAS_ABI_HEADERS
  18 # include BOOST_ABI_PREFIX
  19 #endif
  20
  21 namespace boost {
  22 namespace context {
  23 namespace detail {
  24
  25 // zero-initialization
  26 thread_local activation_record * current_rec;
  27 thread_local static std::size_t counter;
  28
  29 // schwarz counter
  30 activation_record_initializer::activation_record_initializer() noexcept {
  31     if ( 0 == counter++) {
  32         current_rec = new activation_record();
  33     }
  34 }
  35
  36 activation_record_initializer::~activation_record_initializer() {
  37     if ( 0 == --counter) {
  38         BOOST_ASSERT( current_rec->is_main_context() );
  39         delete current_rec;
  40     }
  41 }
  42
  43 }
  44
  45 namespace detail {
  46
  47 activation_record *&
  48 activation_record::current() noexcept {
  49     // initialized the first time control passes; per thread
  50     thread_local static activation_record_initializer initializer;
  51     return current_rec;
  52 }
  53
  54 }
  55
  56 }}
  57
  58 #ifdef BOOST_HAS_ABI_HEADERS
  59 # include BOOST_ABI_SUFFIX
  60 #endif