Mercurial > hg > vamp-build-and-test
diff DEPENDENCIES/generic/include/boost/thread/pthread/shared_mutex.hpp @ 16:2665513ce2d3
Add boost headers
author | Chris Cannam |
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date | Tue, 05 Aug 2014 11:11:38 +0100 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/DEPENDENCIES/generic/include/boost/thread/pthread/shared_mutex.hpp Tue Aug 05 11:11:38 2014 +0100 @@ -0,0 +1,716 @@ +#ifndef BOOST_THREAD_PTHREAD_SHARED_MUTEX_HPP +#define BOOST_THREAD_PTHREAD_SHARED_MUTEX_HPP + +// (C) Copyright 2006-8 Anthony Williams +// (C) Copyright 2012 Vicente J. Botet Escriba +// +// Distributed under the Boost Software License, Version 1.0. (See +// accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) + +#include <boost/assert.hpp> +#include <boost/static_assert.hpp> +#include <boost/thread/mutex.hpp> +#include <boost/thread/condition_variable.hpp> +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS +#include <boost/thread/detail/thread_interruption.hpp> +#endif +#ifdef BOOST_THREAD_USES_CHRONO +#include <boost/chrono/system_clocks.hpp> +#include <boost/chrono/ceil.hpp> +#endif +#include <boost/thread/detail/delete.hpp> +#include <boost/assert.hpp> + +#include <boost/config/abi_prefix.hpp> + +namespace boost +{ + class shared_mutex + { + private: + class state_data + { + public: + state_data () : + shared_count(0), + exclusive(false), + upgrade(false), + exclusive_waiting_blocked(false) + {} + + void assert_free() const + { + BOOST_ASSERT( ! exclusive ); + BOOST_ASSERT( ! upgrade ); + BOOST_ASSERT( shared_count==0 ); + } + + void assert_locked() const + { + BOOST_ASSERT( exclusive ); + BOOST_ASSERT( shared_count==0 ); + BOOST_ASSERT( ! upgrade ); + } + + void assert_lock_shared () const + { + BOOST_ASSERT( ! exclusive ); + BOOST_ASSERT( shared_count>0 ); + //BOOST_ASSERT( (! upgrade) || (shared_count>1)); + // if upgraded there are at least 2 threads sharing the mutex, + // except when unlock_upgrade_and_lock has decreased the number of readers but has not taken yet exclusive ownership. + } + + void assert_lock_upgraded () const + { + BOOST_ASSERT( ! exclusive ); + BOOST_ASSERT( upgrade ); + BOOST_ASSERT( shared_count>0 ); + } + + void assert_lock_not_upgraded () const + { + BOOST_ASSERT( ! upgrade ); + } + + bool can_lock () const + { + return ! (shared_count || exclusive); + } + + void exclusive_blocked (bool blocked) + { + exclusive_waiting_blocked = blocked; + } + + void lock () + { + exclusive = true; + } + + void unlock () + { + exclusive = false; + exclusive_waiting_blocked = false; + } + + bool can_lock_shared () const + { + return ! (exclusive || exclusive_waiting_blocked); + } + + bool more_shared () const + { + return shared_count > 0 ; + } + unsigned get_shared_count () const + { + return shared_count ; + } + unsigned lock_shared () + { + return ++shared_count; + } + + + void unlock_shared () + { + --shared_count; + } + + bool unlock_shared_downgrades() + { + if (upgrade) { + upgrade=false; + exclusive=true; + return true; + } else { + exclusive_waiting_blocked=false; + return false; + } + } + + void lock_upgrade () + { + ++shared_count; + upgrade=true; + } + bool can_lock_upgrade () const + { + return ! (exclusive || exclusive_waiting_blocked || upgrade); + } + + void unlock_upgrade () + { + upgrade=false; + --shared_count; + } + + //private: + unsigned shared_count; + bool exclusive; + bool upgrade; + bool exclusive_waiting_blocked; + }; + + + + state_data state; + boost::mutex state_change; + boost::condition_variable shared_cond; + boost::condition_variable exclusive_cond; + boost::condition_variable upgrade_cond; + + void release_waiters() + { + exclusive_cond.notify_one(); + shared_cond.notify_all(); + } + + public: + + BOOST_THREAD_NO_COPYABLE(shared_mutex) + + shared_mutex() + { + } + + ~shared_mutex() + { + } + + void lock_shared() + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + while(!state.can_lock_shared()) + { + shared_cond.wait(lk); + } + state.lock_shared(); + } + + bool try_lock_shared() + { + boost::unique_lock<boost::mutex> lk(state_change); + + if(!state.can_lock_shared()) + { + return false; + } + state.lock_shared(); + return true; + } + +#if defined BOOST_THREAD_USES_DATETIME + bool timed_lock_shared(system_time const& timeout) + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + + while(!state.can_lock_shared()) + { + if(!shared_cond.timed_wait(lk,timeout)) + { + return false; + } + } + state.lock_shared(); + return true; + } + + template<typename TimeDuration> + bool timed_lock_shared(TimeDuration const & relative_time) + { + return timed_lock_shared(get_system_time()+relative_time); + } +#endif +#ifdef BOOST_THREAD_USES_CHRONO + template <class Rep, class Period> + bool try_lock_shared_for(const chrono::duration<Rep, Period>& rel_time) + { + return try_lock_shared_until(chrono::steady_clock::now() + rel_time); + } + template <class Clock, class Duration> + bool try_lock_shared_until(const chrono::time_point<Clock, Duration>& abs_time) + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + + while(!state.can_lock_shared()) + //while(state.exclusive || state.exclusive_waiting_blocked) + { + if(cv_status::timeout==shared_cond.wait_until(lk,abs_time)) + { + return false; + } + } + state.lock_shared(); + return true; + } +#endif + void unlock_shared() + { + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_lock_shared(); + state.unlock_shared(); + if (! state.more_shared()) + { + if (state.upgrade) + { + // As there is a thread doing a unlock_upgrade_and_lock that is waiting for ! state.more_shared() + // avoid other threads to lock, lock_upgrade or lock_shared, so only this thread is notified. + state.upgrade=false; + state.exclusive=true; + lk.unlock(); + upgrade_cond.notify_one(); + } + else + { + state.exclusive_waiting_blocked=false; + lk.unlock(); + } + release_waiters(); + } + } + + void lock() + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + + while (state.shared_count || state.exclusive) + { + state.exclusive_waiting_blocked=true; + exclusive_cond.wait(lk); + } + state.exclusive=true; + } + +#if defined BOOST_THREAD_USES_DATETIME + bool timed_lock(system_time const& timeout) + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + + while(state.shared_count || state.exclusive) + { + state.exclusive_waiting_blocked=true; + if(!exclusive_cond.timed_wait(lk,timeout)) + { + if(state.shared_count || state.exclusive) + { + state.exclusive_waiting_blocked=false; + release_waiters(); + return false; + } + break; + } + } + state.exclusive=true; + return true; + } + + template<typename TimeDuration> + bool timed_lock(TimeDuration const & relative_time) + { + return timed_lock(get_system_time()+relative_time); + } +#endif +#ifdef BOOST_THREAD_USES_CHRONO + template <class Rep, class Period> + bool try_lock_for(const chrono::duration<Rep, Period>& rel_time) + { + return try_lock_until(chrono::steady_clock::now() + rel_time); + } + template <class Clock, class Duration> + bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time) + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + + while(state.shared_count || state.exclusive) + { + state.exclusive_waiting_blocked=true; + if(cv_status::timeout == exclusive_cond.wait_until(lk,abs_time)) + { + if(state.shared_count || state.exclusive) + { + state.exclusive_waiting_blocked=false; + release_waiters(); + return false; + } + break; + } + } + state.exclusive=true; + return true; + } +#endif + + bool try_lock() + { + boost::unique_lock<boost::mutex> lk(state_change); + + if(state.shared_count || state.exclusive) + { + return false; + } + else + { + state.exclusive=true; + return true; + } + + } + + void unlock() + { + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_locked(); + state.exclusive=false; + state.exclusive_waiting_blocked=false; + state.assert_free(); + release_waiters(); + } + + void lock_upgrade() + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + while(state.exclusive || state.exclusive_waiting_blocked || state.upgrade) + { + shared_cond.wait(lk); + } + state.lock_shared(); + state.upgrade=true; + } + +#if defined BOOST_THREAD_USES_DATETIME + bool timed_lock_upgrade(system_time const& timeout) + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + while(state.exclusive || state.exclusive_waiting_blocked || state.upgrade) + { + if(!shared_cond.timed_wait(lk,timeout)) + { + if(state.exclusive || state.exclusive_waiting_blocked || state.upgrade) + { + return false; + } + break; + } + } + state.lock_shared(); + state.upgrade=true; + return true; + } + + template<typename TimeDuration> + bool timed_lock_upgrade(TimeDuration const & relative_time) + { + return timed_lock_upgrade(get_system_time()+relative_time); + } +#endif +#ifdef BOOST_THREAD_USES_CHRONO + template <class Rep, class Period> + bool try_lock_upgrade_for(const chrono::duration<Rep, Period>& rel_time) + { + return try_lock_upgrade_until(chrono::steady_clock::now() + rel_time); + } + template <class Clock, class Duration> + bool try_lock_upgrade_until(const chrono::time_point<Clock, Duration>& abs_time) + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + while(state.exclusive || state.exclusive_waiting_blocked || state.upgrade) + { + if(cv_status::timeout == shared_cond.wait_until(lk,abs_time)) + { + if(state.exclusive || state.exclusive_waiting_blocked || state.upgrade) + { + return false; + } + break; + } + } + state.lock_shared(); + state.upgrade=true; + return true; + } +#endif + bool try_lock_upgrade() + { + boost::unique_lock<boost::mutex> lk(state_change); + if(state.exclusive || state.exclusive_waiting_blocked || state.upgrade) + { + return false; + } + else + { + state.lock_shared(); + state.upgrade=true; + state.assert_lock_upgraded(); + return true; + } + } + + void unlock_upgrade() + { + boost::unique_lock<boost::mutex> lk(state_change); + //state.upgrade=false; + state.unlock_upgrade(); + if(! state.more_shared() ) + { + state.exclusive_waiting_blocked=false; + release_waiters(); + } else { + shared_cond.notify_all(); + } + } + + // Upgrade <-> Exclusive + void unlock_upgrade_and_lock() + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_lock_upgraded(); + state.unlock_shared(); + while (state.more_shared()) + { + upgrade_cond.wait(lk); + } + state.upgrade=false; + state.exclusive=true; + state.assert_locked(); + } + + void unlock_and_lock_upgrade() + { + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_locked(); + state.exclusive=false; + state.upgrade=true; + state.lock_shared(); + state.exclusive_waiting_blocked=false; + state.assert_lock_upgraded(); + release_waiters(); + } + + bool try_unlock_upgrade_and_lock() + { + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_lock_upgraded(); + if( !state.exclusive + && !state.exclusive_waiting_blocked + && state.upgrade + && state.shared_count==1) + { + state.shared_count=0; + state.exclusive=true; + state.upgrade=false; + state.assert_locked(); + return true; + } + return false; + } +#ifdef BOOST_THREAD_USES_CHRONO + template <class Rep, class Period> + bool + try_unlock_upgrade_and_lock_for( + const chrono::duration<Rep, Period>& rel_time) + { + return try_unlock_upgrade_and_lock_until( + chrono::steady_clock::now() + rel_time); + } + template <class Clock, class Duration> + bool + try_unlock_upgrade_and_lock_until( + const chrono::time_point<Clock, Duration>& abs_time) + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_lock_upgraded(); + if (state.shared_count != 1) + { + for (;;) + { + cv_status status = shared_cond.wait_until(lk,abs_time); + if (state.shared_count == 1) + break; + if(status == cv_status::timeout) + return false; + } + } + state.upgrade=false; + state.exclusive=true; + state.exclusive_waiting_blocked=false; + state.shared_count=0; + return true; + } +#endif + + // Shared <-> Exclusive + void unlock_and_lock_shared() + { + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_locked(); + state.exclusive=false; + state.lock_shared(); + state.exclusive_waiting_blocked=false; + release_waiters(); + } + +#ifdef BOOST_THREAD_PROVIDES_SHARED_MUTEX_UPWARDS_CONVERSIONS + bool try_unlock_shared_and_lock() + { + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_lock_shared(); + if( !state.exclusive + && !state.exclusive_waiting_blocked + && !state.upgrade + && state.shared_count==1) + { + state.shared_count=0; + state.exclusive=true; + return true; + } + return false; + } +#ifdef BOOST_THREAD_USES_CHRONO + template <class Rep, class Period> + bool + try_unlock_shared_and_lock_for( + const chrono::duration<Rep, Period>& rel_time) + { + return try_unlock_shared_and_lock_until( + chrono::steady_clock::now() + rel_time); + } + template <class Clock, class Duration> + bool + try_unlock_shared_and_lock_until( + const chrono::time_point<Clock, Duration>& abs_time) + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_lock_shared(); + if (state.shared_count != 1) + { + for (;;) + { + cv_status status = shared_cond.wait_until(lk,abs_time); + if (state.shared_count == 1) + break; + if(status == cv_status::timeout) + return false; + } + } + state.upgrade=false; + state.exclusive=true; + state.exclusive_waiting_blocked=false; + state.shared_count=0; + return true; + } +#endif +#endif + + // Shared <-> Upgrade + void unlock_upgrade_and_lock_shared() + { + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_lock_upgraded(); + state.upgrade=false; + state.exclusive_waiting_blocked=false; + release_waiters(); + } + +#ifdef BOOST_THREAD_PROVIDES_SHARED_MUTEX_UPWARDS_CONVERSIONS + bool try_unlock_shared_and_lock_upgrade() + { + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_lock_shared(); + if( !state.exclusive + && !state.exclusive_waiting_blocked + && !state.upgrade + ) + { + state.upgrade=true; + return true; + } + return false; + } +#ifdef BOOST_THREAD_USES_CHRONO + template <class Rep, class Period> + bool + try_unlock_shared_and_lock_upgrade_for( + const chrono::duration<Rep, Period>& rel_time) + { + return try_unlock_shared_and_lock_upgrade_until( + chrono::steady_clock::now() + rel_time); + } + template <class Clock, class Duration> + bool + try_unlock_shared_and_lock_upgrade_until( + const chrono::time_point<Clock, Duration>& abs_time) + { +#if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS + boost::this_thread::disable_interruption do_not_disturb; +#endif + boost::unique_lock<boost::mutex> lk(state_change); + state.assert_lock_shared(); + if( state.exclusive + || state.exclusive_waiting_blocked + || state.upgrade + ) + { + for (;;) + { + cv_status status = exclusive_cond.wait_until(lk,abs_time); + if( ! state.exclusive + && ! state.exclusive_waiting_blocked + && ! state.upgrade + ) + break; + if(status == cv_status::timeout) + return false; + } + } + state.upgrade=true; + return true; + } +#endif +#endif + }; + + typedef shared_mutex upgrade_mutex; +} + +#include <boost/config/abi_suffix.hpp> + +#endif