ceph/src/boost/boost/smart_ptr/detail/spinlock_nt.hpp

   1 #ifndef BOOST_SMART_PTR_DETAIL_SPINLOCK_NT_HPP_INCLUDED
   2 #define BOOST_SMART_PTR_DETAIL_SPINLOCK_NT_HPP_INCLUDED
   3
   4 // MS compatible compilers support #pragma once
   5
   6 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
   7 # pragma once
   8 #endif
   9
  10 //
  11 //  Copyright (c) 2008 Peter Dimov
  12 //
  13 //  Distributed under the Boost Software License, Version 1.0.
  14 //  See accompanying file LICENSE_1_0.txt or copy at
  15 //  http://www.boost.org/LICENSE_1_0.txt)
  16 //
  17
  18 #include <boost/assert.hpp>
  19
  20 #if defined(BOOST_SP_REPORT_IMPLEMENTATION)
  21
  22 #include <boost/config/pragma_message.hpp>
  23 BOOST_PRAGMA_MESSAGE("Using single-threaded spinlock emulation")
  24
  25 #endif
  26
  27 namespace boost
  28 {
  29
  30 namespace detail
  31 {
  32
  33 class spinlock
  34 {
  35 public:
  36
  37     bool locked_;
  38
  39 public:
  40
  41     inline bool try_lock()
  42     {
  43         if( locked_ )
  44         {
  45             return false;
  46         }
  47         else
  48         {
  49             locked_ = true;
  50             return true;
  51         }
  52     }
  53
  54     inline void lock()
  55     {
  56         BOOST_ASSERT( !locked_ );
  57         locked_ = true;
  58     }
  59
  60     inline void unlock()
  61     {
  62         BOOST_ASSERT( locked_ );
  63         locked_ = false;
  64     }
  65
  66 public:
  67
  68     class scoped_lock
  69     {
  70     private:
  71
  72         spinlock & sp_;
  73
  74         scoped_lock( scoped_lock const & );
  75         scoped_lock & operator=( scoped_lock const & );
  76
  77     public:
  78
  79         explicit scoped_lock( spinlock & sp ): sp_( sp )
  80         {
  81             sp.lock();
  82         }
  83
  84         ~scoped_lock()
  85         {
  86             sp_.unlock();
  87         }
  88     };
  89 };
  90
  91 } // namespace detail
  92 } // namespace boost
  93
  94 #define BOOST_DETAIL_SPINLOCK_INIT { false }
  95
  96 #endif // #ifndef BOOST_SMART_PTR_DETAIL_SPINLOCK_NT_HPP_INCLUDED