Chris@16: // (C) Copyright 2010 Just Software Solutions Ltd http://www.justsoftwaresolutions.co.uk
Chris@16: // (C) Copyright 2012 Vicente J. Botet Escriba
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See
Chris@16: // accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: 
Chris@16: #ifndef BOOST_THREAD_SYNCHRONIZED_VALUE_HPP
Chris@16: #define BOOST_THREAD_SYNCHRONIZED_VALUE_HPP
Chris@16: 
Chris@16: #include <boost/thread/detail/config.hpp>
Chris@16: 
Chris@16: #include <boost/thread/detail/move.hpp>
Chris@16: #include <boost/thread/mutex.hpp>
Chris@16: #include <boost/thread/lock_types.hpp>
Chris@16: #include <boost/thread/lock_guard.hpp>
Chris@16: #include <boost/thread/lock_algorithms.hpp>
Chris@16: #include <boost/thread/lock_factories.hpp>
Chris@16: #include <boost/thread/strict_lock.hpp>
Chris@101: #include <boost/core/swap.hpp>
Chris@16: #include <boost/utility/declval.hpp>
Chris@16: //#include <boost/type_traits.hpp>
Chris@16: //#include <boost/thread/detail/is_nothrow_default_constructible.hpp>
Chris@16: //#if ! defined BOOST_NO_CXX11_HDR_TYPE_TRAITS
Chris@16: //#include <type_traits>
Chris@16: //#endif
Chris@16: 
Chris@16: #if ! defined(BOOST_THREAD_NO_SYNCHRONIZE)
Chris@16: #include <tuple> // todo change to <boost/tuple.hpp> once Boost.Tuple or Boost.Fusion provides Move semantics on C++98 compilers.
Chris@16: #include <functional>
Chris@16: #endif
Chris@16: 
Chris@16: #include <boost/utility/result_of.hpp>
Chris@16: 
Chris@16: #include <boost/config/abi_prefix.hpp>
Chris@16: 
Chris@16: namespace boost
Chris@16: {
Chris@16: 
Chris@16:   /**
Chris@16:    * strict lock providing a const pointer access to the synchronized value type.
Chris@16:    *
Chris@16:    * @param T the value type.
Chris@16:    * @param Lockable the mutex type protecting the value type.
Chris@16:    */
Chris@16:   template <typename T, typename Lockable = mutex>
Chris@16:   class const_strict_lock_ptr
Chris@16:   {
Chris@16:   public:
Chris@16:     typedef T value_type;
Chris@16:     typedef Lockable mutex_type;
Chris@16:   protected:
Chris@16: 
Chris@16:     // this should be a strict_lock, but unique_lock is needed to be able to return it.
Chris@16:     boost::unique_lock<mutex_type> lk_;
Chris@16:     T const& value_;
Chris@16: 
Chris@16:   public:
Chris@16:     BOOST_THREAD_MOVABLE_ONLY( const_strict_lock_ptr )
Chris@16: 
Chris@16:     /**
Chris@16:      * @param value constant reference of the value to protect.
Chris@16:      * @param mtx reference to the mutex used to protect the value.
Chris@16:      * @effects locks the mutex @c mtx, stores a reference to it and to the value type @c value.
Chris@16:      */
Chris@16:     const_strict_lock_ptr(T const& val, Lockable & mtx) :
Chris@16:       lk_(mtx), value_(val)
Chris@16:     {
Chris@16:     }
Chris@16:     const_strict_lock_ptr(T const& val, Lockable & mtx, adopt_lock_t tag) BOOST_NOEXCEPT :
Chris@16:       lk_(mtx, tag), value_(val)
Chris@16:     {
Chris@16:     }
Chris@16:     /**
Chris@16:      * Move constructor.
Chris@16:      * @effects takes ownership of the mutex owned by @c other, stores a reference to the mutex and the value type of @c other.
Chris@16:      */
Chris@16:     const_strict_lock_ptr(BOOST_THREAD_RV_REF(const_strict_lock_ptr) other) BOOST_NOEXCEPT
Chris@16:     : lk_(boost::move(BOOST_THREAD_RV(other).lk_)),value_(BOOST_THREAD_RV(other).value_)
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     ~const_strict_lock_ptr()
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * @return a constant pointer to the protected value
Chris@16:      */
Chris@16:     const T* operator->() const
Chris@16:     {
Chris@16:       return &value_;
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * @return a constant reference to the protected value
Chris@16:      */
Chris@16:     const T& operator*() const
Chris@16:     {
Chris@16:       return value_;
Chris@16:     }
Chris@16: 
Chris@16:   };
Chris@16: 
Chris@16:   /**
Chris@16:    * strict lock providing a pointer access to the synchronized value type.
Chris@16:    *
Chris@16:    * @param T the value type.
Chris@16:    * @param Lockable the mutex type protecting the value type.
Chris@16:    */
Chris@16:   template <typename T, typename Lockable = mutex>
Chris@16:   class strict_lock_ptr : public const_strict_lock_ptr<T,Lockable>
Chris@16:   {
Chris@16:     typedef const_strict_lock_ptr<T,Lockable> base_type;
Chris@16:   public:
Chris@16:     BOOST_THREAD_MOVABLE_ONLY( strict_lock_ptr )
Chris@16: 
Chris@16:     /**
Chris@16:      * @param value reference of the value to protect.
Chris@16:      * @param mtx reference to the mutex used to protect the value.
Chris@16:      * @effects locks the mutex @c mtx, stores a reference to it and to the value type @c value.
Chris@16:      */
Chris@16:     strict_lock_ptr(T & val, Lockable & mtx) :
Chris@16:     base_type(val, mtx)
Chris@16:     {
Chris@16:     }
Chris@16:     strict_lock_ptr(T & val, Lockable & mtx, adopt_lock_t tag) :
Chris@16:     base_type(val, mtx, tag)
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * Move constructor.
Chris@16:      * @effects takes ownership of the mutex owned by @c other, stores a reference to the mutex and the value type of @c other.
Chris@16:      */
Chris@16:     strict_lock_ptr(BOOST_THREAD_RV_REF(strict_lock_ptr) other)
Chris@16:     : base_type(boost::move(static_cast<base_type&>(other)))
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     ~strict_lock_ptr()
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * @return a pointer to the protected value
Chris@16:      */
Chris@16:     T* operator->()
Chris@16:     {
Chris@16:       return const_cast<T*>(&this->value_);
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * @return a reference to the protected value
Chris@16:      */
Chris@16:     T& operator*()
Chris@16:     {
Chris@16:       return const_cast<T&>(this->value_);
Chris@16:     }
Chris@16: 
Chris@16:   };
Chris@16: 
Chris@16:   template <typename SV>
Chris@16:   struct synchronized_value_strict_lock_ptr
Chris@16:   {
Chris@16:    typedef strict_lock_ptr<typename SV::value_type, typename SV::mutex_type> type;
Chris@16:   };
Chris@16: 
Chris@16:   template <typename SV>
Chris@16:   struct synchronized_value_strict_lock_ptr<const SV>
Chris@16:   {
Chris@16:    typedef const_strict_lock_ptr<typename SV::value_type, typename SV::mutex_type> type;
Chris@16:   };
Chris@16:   /**
Chris@16:    * unique_lock providing a const pointer access to the synchronized value type.
Chris@16:    *
Chris@16:    * An object of type const_unique_lock_ptr is a unique_lock that provides a const pointer access to the synchronized value type.
Chris@16:    * As unique_lock controls the ownership of a lockable object within a scope.
Chris@16:    * Ownership of the lockable object may be acquired at construction or after construction,
Chris@16:    * and may be transferred, after acquisition, to another const_unique_lock_ptr object.
Chris@16:    * Objects of type const_unique_lock_ptr are not copyable but are movable.
Chris@16:    * The behavior of a program is undefined if the mutex and the value type
Chris@16:    * pointed do not exist for the entire remaining lifetime of the const_unique_lock_ptr object.
Chris@16:    * The supplied Mutex type shall meet the BasicLockable requirements.
Chris@16:    *
Chris@16:    * @note const_unique_lock_ptr<T, Lockable> meets the Lockable requirements.
Chris@16:    * If Lockable meets the TimedLockable requirements, const_unique_lock_ptr<T,Lockable>
Chris@16:    * also meets the TimedLockable requirements.
Chris@16:    *
Chris@16:    * @param T the value type.
Chris@16:    * @param Lockable the mutex type protecting the value type.
Chris@16:    */
Chris@16:   template <typename T, typename Lockable = mutex>
Chris@16:   class const_unique_lock_ptr : public unique_lock<Lockable>
Chris@16:   {
Chris@16:     typedef unique_lock<Lockable> base_type;
Chris@16:   public:
Chris@16:     typedef T value_type;
Chris@16:     typedef Lockable mutex_type;
Chris@16:   protected:
Chris@16:     T const& value_;
Chris@16: 
Chris@16:   public:
Chris@16:     BOOST_THREAD_MOVABLE_ONLY(const_unique_lock_ptr)
Chris@16: 
Chris@16:     /**
Chris@16:      * @param value reference of the value to protect.
Chris@16:      * @param mtx reference to the mutex used to protect the value.
Chris@16:      *
Chris@16:      * @requires If mutex_type is not a recursive mutex the calling thread does not own the mutex.
Chris@16:      *
Chris@16:      * @effects locks the mutex @c mtx, stores a reference to it and to the value type @c value.
Chris@16:      */
Chris@16:     const_unique_lock_ptr(T const& val, Lockable & mtx)
Chris@16:     : base_type(mtx), value_(val)
Chris@16:     {
Chris@16:     }
Chris@16:     /**
Chris@16:      * @param value reference of the value to protect.
Chris@16:      * @param mtx reference to the mutex used to protect the value.
Chris@16:      * @param tag of type adopt_lock_t used to differentiate the constructor.
Chris@16:      * @requires The calling thread own the mutex.
Chris@16:      * @effects stores a reference to it and to the value type @c value taking ownership.
Chris@16:      */
Chris@16:     const_unique_lock_ptr(T const& val, Lockable & mtx, adopt_lock_t) BOOST_NOEXCEPT
Chris@16:     : base_type(mtx, adopt_lock), value_(val)
Chris@16:     {
Chris@16:     }
Chris@16:     /**
Chris@16:      * @param value reference of the value to protect.
Chris@16:      * @param mtx reference to the mutex used to protect the value.
Chris@16:      * @param tag of type defer_lock_t used to differentiate the constructor.
Chris@16:      * @effects stores a reference to it and to the value type @c value c.
Chris@16:      */
Chris@16:     const_unique_lock_ptr(T const& val, Lockable & mtx, defer_lock_t) BOOST_NOEXCEPT
Chris@16:     : base_type(mtx, defer_lock), value_(val)
Chris@16:     {
Chris@16:     }
Chris@16:     /**
Chris@16:      * @param value reference of the value to protect.
Chris@16:      * @param mtx reference to the mutex used to protect the value.
Chris@16:      * @param tag of type try_to_lock_t used to differentiate the constructor.
Chris@16:      * @requires If mutex_type is not a recursive mutex the calling thread does not own the mutex.
Chris@16:      * @effects try to lock the mutex @c mtx, stores a reference to it and to the value type @c value.
Chris@16:      */
Chris@16:     const_unique_lock_ptr(T const& val, Lockable & mtx, try_to_lock_t) BOOST_NOEXCEPT
Chris@16:     : base_type(mtx, try_to_lock), value_(val)
Chris@16:     {
Chris@16:     }
Chris@16:     /**
Chris@16:      * Move constructor.
Chris@16:      * @effects takes ownership of the mutex owned by @c other, stores a reference to the mutex and the value type of @c other.
Chris@16:      */
Chris@16:     const_unique_lock_ptr(BOOST_THREAD_RV_REF(const_unique_lock_ptr) other) BOOST_NOEXCEPT
Chris@16:     : base_type(boost::move(static_cast<base_type&>(other))), value_(BOOST_THREAD_RV(other).value_)
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * @effects If owns calls unlock() on the owned mutex.
Chris@16:      */
Chris@16:     ~const_unique_lock_ptr()
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * @return a constant pointer to the protected value
Chris@16:      */
Chris@16:     const T* operator->() const
Chris@16:     {
Chris@16:       BOOST_ASSERT (this->owns_lock());
Chris@16:       return &value_;
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * @return a constant reference to the protected value
Chris@16:      */
Chris@16:     const T& operator*() const
Chris@16:     {
Chris@16:       BOOST_ASSERT (this->owns_lock());
Chris@16:       return value_;
Chris@16:     }
Chris@16: 
Chris@16:   };
Chris@16: 
Chris@16:   /**
Chris@16:    * unique lock providing a pointer access to the synchronized value type.
Chris@16:    *
Chris@16:    * @param T the value type.
Chris@16:    * @param Lockable the mutex type protecting the value type.
Chris@16:    */
Chris@16:   template <typename T, typename Lockable = mutex>
Chris@16:   class unique_lock_ptr : public const_unique_lock_ptr<T, Lockable>
Chris@16:   {
Chris@16:     typedef const_unique_lock_ptr<T, Lockable> base_type;
Chris@16:   public:
Chris@16:     typedef T value_type;
Chris@16:     typedef Lockable mutex_type;
Chris@16: 
Chris@16:     BOOST_THREAD_MOVABLE_ONLY(unique_lock_ptr)
Chris@16: 
Chris@16:     /**
Chris@16:      * @param value reference of the value to protect.
Chris@16:      * @param mtx reference to the mutex used to protect the value.
Chris@16:      * @effects locks the mutex @c mtx, stores a reference to it and to the value type @c value.
Chris@16:      */
Chris@16:     unique_lock_ptr(T & val, Lockable & mtx)
Chris@16:     : base_type(val, mtx)
Chris@16:     {
Chris@16:     }
Chris@16:     /**
Chris@16:      * @param value reference of the value to protect.
Chris@16:      * @param mtx reference to the mutex used to protect the value.
Chris@16:      * @param tag of type adopt_lock_t used to differentiate the constructor.
Chris@16:      * @effects stores a reference to it and to the value type @c value taking ownership.
Chris@16:      */
Chris@16:     unique_lock_ptr(T & value, Lockable & mtx, adopt_lock_t) BOOST_NOEXCEPT
Chris@16:     : base_type(value, mtx, adopt_lock)
Chris@16:     {
Chris@16:     }
Chris@16:     /**
Chris@16:      * @param value reference of the value to protect.
Chris@16:      * @param mtx reference to the mutex used to protect the value.
Chris@16:      * @param tag of type defer_lock_t used to differentiate the constructor.
Chris@16:      * @effects stores a reference to it and to the value type @c value c.
Chris@16:      */
Chris@16:     unique_lock_ptr(T & value, Lockable & mtx, defer_lock_t) BOOST_NOEXCEPT
Chris@16:     : base_type(value, mtx, defer_lock)
Chris@16:     {
Chris@16:     }
Chris@16:     /**
Chris@16:      * @param value reference of the value to protect.
Chris@16:      * @param mtx reference to the mutex used to protect the value.
Chris@16:      * @param tag of type try_to_lock_t used to differentiate the constructor.
Chris@16:      * @effects try to lock the mutex @c mtx, stores a reference to it and to the value type @c value.
Chris@16:      */
Chris@16:     unique_lock_ptr(T & value, Lockable & mtx, try_to_lock_t) BOOST_NOEXCEPT
Chris@16:     : base_type(value, mtx, try_to_lock)
Chris@16:     {
Chris@16:     }
Chris@16:     /**
Chris@16:      * Move constructor.
Chris@16:      * @effects takes ownership of the mutex owned by @c other, stores a reference to the mutex and the value type of @c other.
Chris@16:      */
Chris@16:     unique_lock_ptr(BOOST_THREAD_RV_REF(unique_lock_ptr) other) BOOST_NOEXCEPT
Chris@16:     : base_type(boost::move(static_cast<base_type&>(other)))
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     ~unique_lock_ptr()
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * @return a pointer to the protected value
Chris@16:      */
Chris@16:     T* operator->()
Chris@16:     {
Chris@16:       BOOST_ASSERT (this->owns_lock());
Chris@16:       return const_cast<T*>(&this->value_);
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * @return a reference to the protected value
Chris@16:      */
Chris@16:     T& operator*()
Chris@16:     {
Chris@16:       BOOST_ASSERT (this->owns_lock());
Chris@16:       return const_cast<T&>(this->value_);
Chris@16:     }
Chris@16: 
Chris@16: 
Chris@16:   };
Chris@16: 
Chris@16:   template <typename SV>
Chris@16:   struct synchronized_value_unique_lock_ptr
Chris@16:   {
Chris@16:    typedef unique_lock_ptr<typename SV::value_type, typename SV::mutex_type> type;
Chris@16:   };
Chris@16: 
Chris@16:   template <typename SV>
Chris@16:   struct synchronized_value_unique_lock_ptr<const SV>
Chris@16:   {
Chris@16:    typedef const_unique_lock_ptr<typename SV::value_type, typename SV::mutex_type> type;
Chris@16:   };
Chris@16:   /**
Chris@16:    * cloaks a value type and the mutex used to protect it together.
Chris@16:    * @param T the value type.
Chris@16:    * @param Lockable the mutex type protecting the value type.
Chris@16:    */
Chris@16:   template <typename T, typename Lockable = mutex>
Chris@16:   class synchronized_value
Chris@16:   {
Chris@16: 
Chris@16: #if ! defined(BOOST_THREAD_NO_MAKE_UNIQUE_LOCKS)
Chris@16: #if ! defined BOOST_NO_CXX11_VARIADIC_TEMPLATES
Chris@16:     template <typename ...SV>
Chris@16:     friend std::tuple<typename synchronized_value_strict_lock_ptr<SV>::type ...> synchronize(SV& ...sv);
Chris@16: #else
Chris@16:     template <typename SV1, typename SV2>
Chris@16:     friend std::tuple<
Chris@16:       typename synchronized_value_strict_lock_ptr<SV1>::type,
Chris@16:       typename synchronized_value_strict_lock_ptr<SV2>::type
Chris@16:     >
Chris@16:     synchronize(SV1& sv1, SV2& sv2);
Chris@16:     template <typename SV1, typename SV2, typename SV3>
Chris@16:     friend std::tuple<
Chris@16:       typename synchronized_value_strict_lock_ptr<SV1>::type,
Chris@16:       typename synchronized_value_strict_lock_ptr<SV2>::type,
Chris@16:       typename synchronized_value_strict_lock_ptr<SV3>::type
Chris@16:     >
Chris@16:     synchronize(SV1& sv1, SV2& sv2, SV3& sv3);
Chris@16: #endif
Chris@16: #endif
Chris@16: 
Chris@16:   public:
Chris@16:     typedef T value_type;
Chris@16:     typedef Lockable mutex_type;
Chris@16:   private:
Chris@16:     T value_;
Chris@16:     mutable mutex_type mtx_;
Chris@16:   public:
Chris@16:     // construction/destruction
Chris@16:     /**
Chris@16:      * Default constructor.
Chris@16:      *
Chris@16:      * @Requires: T is DefaultConstructible
Chris@16:      */
Chris@16:     synchronized_value()
Chris@16:     //BOOST_NOEXCEPT_IF(is_nothrow_default_constructible<T>::value)
Chris@16:     : value_()
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * Constructor from copy constructible value.
Chris@16:      *
Chris@16:      * Requires: T is CopyConstructible
Chris@16:      */
Chris@16:     synchronized_value(T const& other)
Chris@16:     //BOOST_NOEXCEPT_IF(is_nothrow_copy_constructible<T>::value)
Chris@16:     : value_(other)
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * Move Constructor.
Chris@16:      *
Chris@16:      * Requires: T is CopyMovable
Chris@16:      */
Chris@16:     synchronized_value(BOOST_THREAD_RV_REF(T) other)
Chris@16:     //BOOST_NOEXCEPT_IF(is_nothrow_move_constructible<T>::value)
Chris@16:     : value_(boost::move(other))
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * Constructor from value type.
Chris@16:      *
Chris@16:      * Requires: T is DefaultConstructible and Assignable
Chris@16:      * Effects: Assigns the value on a scope protected by the mutex of the rhs. The mutex is not copied.
Chris@16:      */
Chris@16:     synchronized_value(synchronized_value const& rhs)
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(rhs.mtx_);
Chris@16:       value_ = rhs.value_;
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * Move Constructor from movable value type
Chris@16:      *
Chris@16:      */
Chris@16:     synchronized_value(BOOST_THREAD_RV_REF(synchronized_value) other)
Chris@16:     {
Chris@101:       strict_lock<mutex_type> lk(BOOST_THREAD_RV(other).mtx_);
Chris@101:       value_= boost::move(BOOST_THREAD_RV(other).value_);
Chris@16:     }
Chris@16: 
Chris@16:     // mutation
Chris@16:     /**
Chris@16:      * Assignment operator.
Chris@16:      *
Chris@16:      * Effects: Copies the underlying value on a scope protected by the two mutexes.
Chris@16:      * The mutex is not copied. The locks are acquired using lock, so deadlock is avoided.
Chris@16:      * For example, there is no problem if one thread assigns a = b and the other assigns b = a.
Chris@16:      *
Chris@16:      * Return: *this
Chris@16:      */
Chris@16: 
Chris@16:     synchronized_value& operator=(synchronized_value const& rhs)
Chris@16:     {
Chris@16:       if(&rhs != this)
Chris@16:       {
Chris@16:         // auto _ = make_unique_locks(mtx_, rhs.mtx_);
Chris@16:         unique_lock<mutex_type> lk1(mtx_, defer_lock);
Chris@16:         unique_lock<mutex_type> lk2(rhs.mtx_, defer_lock);
Chris@16:         lock(lk1,lk2);
Chris@16: 
Chris@16:         value_ = rhs.value_;
Chris@16:       }
Chris@16:       return *this;
Chris@16:     }
Chris@16:     /**
Chris@16:      * Assignment operator from a T const&.
Chris@16:      * Effects: The operator copies the value on a scope protected by the mutex.
Chris@16:      * Return: *this
Chris@16:      */
Chris@16:     synchronized_value& operator=(value_type const& val)
Chris@16:     {
Chris@16:       {
Chris@16:         strict_lock<mutex_type> lk(mtx_);
Chris@16:         value_ = val;
Chris@16:       }
Chris@16:       return *this;
Chris@16:     }
Chris@16: 
Chris@16:     //observers
Chris@16:     /**
Chris@16:      * Explicit conversion to value type.
Chris@16:      *
Chris@16:      * Requires: T is CopyConstructible
Chris@16:      * Return: A copy of the protected value obtained on a scope protected by the mutex.
Chris@16:      *
Chris@16:      */
Chris@16:     T get() const
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(mtx_);
Chris@16:       return value_;
Chris@16:     }
Chris@16:     /**
Chris@16:      * Explicit conversion to value type.
Chris@16:      *
Chris@16:      * Requires: T is CopyConstructible
Chris@16:      * Return: A copy of the protected value obtained on a scope protected by the mutex.
Chris@16:      *
Chris@16:      */
Chris@16: #if ! defined(BOOST_NO_CXX11_EXPLICIT_CONVERSION_OPERATORS)
Chris@16:     explicit operator T() const
Chris@16:     {
Chris@16:       return get();
Chris@16:     }
Chris@16: #endif
Chris@16: 
Chris@16:     /**
Chris@16:      * value type getter.
Chris@16:      *
Chris@16:      * Return: A constant reference to the protected value.
Chris@16:      *
Chris@16:      * Note: Not thread safe
Chris@16:      *
Chris@16:      */
Chris@16:     T const& value() const
Chris@16:     {
Chris@16:       return value_;
Chris@16:     }
Chris@16:     /**
Chris@16:      * mutex getter.
Chris@16:      *
Chris@16:      * Return: A constant reference to the protecting mutex.
Chris@16:      *
Chris@16:      * Note: Not thread safe
Chris@16:      *
Chris@16:      */
Chris@16:     mutex_type const& mutex() const
Chris@16:     {
Chris@16:       return mtx_;
Chris@16:     }
Chris@16:     /**
Chris@16:      * Swap
Chris@16:      *
Chris@16:      * Effects: Swaps the data. Again, locks are acquired using lock(). The mutexes are not swapped.
Chris@16:      * A swap method accepts a T& and swaps the data inside a critical section.
Chris@16:      * This is by far the preferred method of changing the guarded datum wholesale because it keeps the lock only
Chris@16:      * for a short time, thus lowering the pressure on the mutex.
Chris@16:      */
Chris@16:     void swap(synchronized_value & rhs)
Chris@16:     {
Chris@16:       if (this == &rhs) {
Chris@16:         return;
Chris@16:       }
Chris@16:       // auto _ = make_unique_locks(mtx_, rhs.mtx_);
Chris@16:       unique_lock<mutex_type> lk1(mtx_, defer_lock);
Chris@16:       unique_lock<mutex_type> lk2(rhs.mtx_, defer_lock);
Chris@16:       lock(lk1,lk2);
Chris@16:       boost::swap(value_, rhs.value_);
Chris@16:     }
Chris@16:     /**
Chris@16:      * Swap with the underlying value type
Chris@16:      *
Chris@16:      * Effects: Swaps the data on a scope protected by the mutex.
Chris@16:      */
Chris@16:     void swap(value_type & rhs)
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(mtx_);
Chris@16:       boost::swap(value_, rhs);
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * Essentially calling a method obj->foo(x, y, z) calls the method foo(x, y, z) inside a critical section as
Chris@16:      * long-lived as the call itself.
Chris@16:      */
Chris@16:     strict_lock_ptr<T,Lockable> operator->()
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((strict_lock_ptr<T,Lockable>(value_, mtx_)));
Chris@16:     }
Chris@16:     /**
Chris@16:      * If the synchronized_value object involved is const-qualified, then you'll only be able to call const methods
Chris@16:      * through operator->. So, for example, vec->push_back("xyz") won't work if vec were const-qualified.
Chris@16:      * The locking mechanism capitalizes on the assumption that const methods don't modify their underlying data.
Chris@16:      */
Chris@16:     const_strict_lock_ptr<T,Lockable> operator->() const
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((const_strict_lock_ptr<T,Lockable>(value_, mtx_)));
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * Call function on a locked block.
Chris@16:      *
Chris@16:      * @requires fct(value_) is well formed.
Chris@16:      *
Chris@16:      * Example
Chris@16:      *   void fun(synchronized_value<vector<int>> & v) {
Chris@16:      *     v ( [](vector<int>> & vec)
Chris@16:      *     {
Chris@16:      *       vec.push_back(42);
Chris@16:      *       assert(vec.back() == 42);
Chris@16:      *     } );
Chris@16:      *   }
Chris@16:      */
Chris@16:     template <typename F>
Chris@16:     inline
Chris@16:     typename boost::result_of<F(value_type&)>::type
Chris@16:     operator()(BOOST_THREAD_RV_REF(F) fct)
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(mtx_);
Chris@16:       return fct(value_);
Chris@16:     }
Chris@16:     template <typename F>
Chris@16:     inline
Chris@16:     typename boost::result_of<F(value_type const&)>::type
Chris@16:     operator()(BOOST_THREAD_RV_REF(F) fct) const
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(mtx_);
Chris@16:       return fct(value_);
Chris@16:     }
Chris@16: 
Chris@16: 
Chris@16: #if defined  BOOST_NO_CXX11_RVALUE_REFERENCES
Chris@16:     template <typename F>
Chris@16:     inline
Chris@16:     typename boost::result_of<F(value_type&)>::type
Chris@16:     operator()(F const & fct)
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(mtx_);
Chris@16:       return fct(value_);
Chris@16:     }
Chris@16:     template <typename F>
Chris@16:     inline
Chris@16:     typename boost::result_of<F(value_type const&)>::type
Chris@16:     operator()(F const & fct) const
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(mtx_);
Chris@16:       return fct(value_);
Chris@16:     }
Chris@16: 
Chris@16:     template <typename R>
Chris@16:     inline
Chris@16:     R operator()(R(*fct)(value_type&))
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(mtx_);
Chris@16:       return fct(value_);
Chris@16:     }
Chris@16:     template <typename R>
Chris@16:     inline
Chris@16:     R operator()(R(*fct)(value_type const&)) const
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(mtx_);
Chris@16:       return fct(value_);
Chris@16:     }
Chris@16: #endif
Chris@16: 
Chris@16: 
Chris@16:     /**
Chris@16:      * The synchronize() factory make easier to lock on a scope.
Chris@16:      * As discussed, operator-> can only lock over the duration of a call, so it is insufficient for complex operations.
Chris@16:      * With synchronize() you get to lock the object in a scoped and to directly access the object inside that scope.
Chris@16:      *
Chris@16:      * Example
Chris@16:      *   void fun(synchronized_value<vector<int>> & v) {
Chris@16:      *     auto&& vec=v.synchronize();
Chris@16:      *     vec.push_back(42);
Chris@16:      *     assert(vec.back() == 42);
Chris@16:      *   }
Chris@16:      */
Chris@16:     strict_lock_ptr<T,Lockable> synchronize()
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((strict_lock_ptr<T,Lockable>(value_, mtx_)));
Chris@16:     }
Chris@16:     const_strict_lock_ptr<T,Lockable> synchronize() const
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((const_strict_lock_ptr<T,Lockable>(value_, mtx_)));
Chris@16:     }
Chris@16: 
Chris@16:     unique_lock_ptr<T,Lockable> unique_synchronize()
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((unique_lock_ptr<T,Lockable>(value_, mtx_)));
Chris@16:     }
Chris@16:     const_unique_lock_ptr<T,Lockable> unique_synchronize() const
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((const_unique_lock_ptr<T,Lockable>(value_, mtx_)));
Chris@16:     }
Chris@16:     unique_lock_ptr<T,Lockable> unique_synchronize(defer_lock_t tag)
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((unique_lock_ptr<T,Lockable>(value_, mtx_, tag)));
Chris@16:     }
Chris@16:     const_unique_lock_ptr<T,Lockable> unique_synchronize(defer_lock_t tag) const
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((const_unique_lock_ptr<T,Lockable>(value_, mtx_, tag)));
Chris@16:     }
Chris@16:     unique_lock_ptr<T,Lockable> defer_synchronize() BOOST_NOEXCEPT
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((unique_lock_ptr<T,Lockable>(value_, mtx_, defer_lock)));
Chris@16:     }
Chris@16:     const_unique_lock_ptr<T,Lockable> defer_synchronize() const BOOST_NOEXCEPT
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((const_unique_lock_ptr<T,Lockable>(value_, mtx_, defer_lock)));
Chris@16:     }
Chris@16:     unique_lock_ptr<T,Lockable> try_to_synchronize() BOOST_NOEXCEPT
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((unique_lock_ptr<T,Lockable>(value_, mtx_, try_to_lock)));
Chris@16:     }
Chris@16:     const_unique_lock_ptr<T,Lockable> try_to_synchronize() const BOOST_NOEXCEPT
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((const_unique_lock_ptr<T,Lockable>(value_, mtx_, try_to_lock)));
Chris@16:     }
Chris@16:     unique_lock_ptr<T,Lockable> adopt_synchronize() BOOST_NOEXCEPT
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((unique_lock_ptr<T,Lockable>(value_, mtx_, adopt_lock)));
Chris@16:     }
Chris@16:     const_unique_lock_ptr<T,Lockable> adopt_synchronize() const BOOST_NOEXCEPT
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF((const_unique_lock_ptr<T,Lockable>(value_, mtx_, adopt_lock)));
Chris@16:     }
Chris@16: 
Chris@16: 
Chris@16: #if ! defined __IBMCPP__
Chris@16:     private:
Chris@16: #endif
Chris@16:     class deref_value
Chris@16:     {
Chris@16:     private:
Chris@16:       friend class synchronized_value;
Chris@16: 
Chris@16:       boost::unique_lock<mutex_type> lk_;
Chris@16:       T& value_;
Chris@16: 
Chris@16:       explicit deref_value(synchronized_value& outer):
Chris@16:       lk_(outer.mtx_),value_(outer.value_)
Chris@16:       {}
Chris@16: 
Chris@16:     public:
Chris@16:       BOOST_THREAD_MOVABLE_ONLY(deref_value)
Chris@16: 
Chris@16:       deref_value(BOOST_THREAD_RV_REF(deref_value) other):
Chris@16:       lk_(boost::move(BOOST_THREAD_RV(other).lk_)),value_(BOOST_THREAD_RV(other).value_)
Chris@16:       {}
Chris@16:       operator T&()
Chris@16:       {
Chris@16:         return value_;
Chris@16:       }
Chris@16: 
Chris@16:       deref_value& operator=(T const& newVal)
Chris@16:       {
Chris@16:         value_=newVal;
Chris@16:         return *this;
Chris@16:       }
Chris@16:     };
Chris@16:     class const_deref_value
Chris@16:     {
Chris@16:     private:
Chris@16:       friend class synchronized_value;
Chris@16: 
Chris@16:       boost::unique_lock<mutex_type> lk_;
Chris@16:       const T& value_;
Chris@16: 
Chris@16:       explicit const_deref_value(synchronized_value const& outer):
Chris@16:       lk_(outer.mtx_), value_(outer.value_)
Chris@16:       {}
Chris@16: 
Chris@16:     public:
Chris@16:       BOOST_THREAD_MOVABLE_ONLY(const_deref_value)
Chris@16: 
Chris@16:       const_deref_value(BOOST_THREAD_RV_REF(const_deref_value) other):
Chris@16:       lk_(boost::move(BOOST_THREAD_RV(other).lk_)), value_(BOOST_THREAD_RV(other).value_)
Chris@16:       {}
Chris@16: 
Chris@16:       operator const T&()
Chris@16:       {
Chris@16:         return value_;
Chris@16:       }
Chris@16:     };
Chris@16: 
Chris@16:   public:
Chris@16:     deref_value operator*()
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF(deref_value(*this));
Chris@16:     }
Chris@16: 
Chris@16:     const_deref_value operator*() const
Chris@16:     {
Chris@16:       return BOOST_THREAD_MAKE_RV_REF(const_deref_value(*this));
Chris@16:     }
Chris@16: 
Chris@16:     // io functions
Chris@16:     /**
Chris@16:      * @requires T is OutputStreamable
Chris@16:      * @effects saves the value type on the output stream @c os.
Chris@16:      */
Chris@16:     template <typename OStream>
Chris@16:     void save(OStream& os) const
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(mtx_);
Chris@16:       os << value_;
Chris@16:     }
Chris@16:     /**
Chris@16:      * @requires T is InputStreamable
Chris@16:      * @effects loads the value type from the input stream @c is.
Chris@16:      */
Chris@16:     template <typename IStream>
Chris@16:     void load(IStream& is) const
Chris@16:     {
Chris@16:       strict_lock<mutex_type> lk(mtx_);
Chris@16:       is >> value_;
Chris@16:     }
Chris@16: 
Chris@16:     // relational operators
Chris@16:     /**
Chris@16:      * @requires T is EqualityComparable
Chris@16:      *
Chris@16:      */
Chris@16:     bool operator==(synchronized_value const& rhs)  const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_, defer_lock);
Chris@16:       unique_lock<mutex_type> lk2(rhs.mtx_, defer_lock);
Chris@16:       lock(lk1,lk2);
Chris@16: 
Chris@16:       return value_ == rhs.value_;
Chris@16:     }
Chris@16:     /**
Chris@16:      * @requires T is LessThanComparable
Chris@16:      *
Chris@16:      */
Chris@16:     bool operator<(synchronized_value const& rhs) const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_, defer_lock);
Chris@16:       unique_lock<mutex_type> lk2(rhs.mtx_, defer_lock);
Chris@16:       lock(lk1,lk2);
Chris@16: 
Chris@16:       return value_ < rhs.value_;
Chris@16:     }
Chris@16:     /**
Chris@16:      * @requires T is GreaterThanComparable
Chris@16:      *
Chris@16:      */
Chris@16:     bool operator>(synchronized_value const& rhs) const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_, defer_lock);
Chris@16:       unique_lock<mutex_type> lk2(rhs.mtx_, defer_lock);
Chris@16:       lock(lk1,lk2);
Chris@16: 
Chris@16:       return value_ > rhs.value_;
Chris@16:     }
Chris@16:     bool operator<=(synchronized_value const& rhs) const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_, defer_lock);
Chris@16:       unique_lock<mutex_type> lk2(rhs.mtx_, defer_lock);
Chris@16:       lock(lk1,lk2);
Chris@16: 
Chris@16:       return value_ <= rhs.value_;
Chris@16:     }
Chris@16:     bool operator>=(synchronized_value const& rhs) const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_, defer_lock);
Chris@16:       unique_lock<mutex_type> lk2(rhs.mtx_, defer_lock);
Chris@16:       lock(lk1,lk2);
Chris@16: 
Chris@16:       return value_ >= rhs.value_;
Chris@16:     }
Chris@16:     bool operator==(value_type const& rhs) const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_);
Chris@16: 
Chris@16:       return value_ == rhs;
Chris@16:     }
Chris@16:     bool operator!=(value_type const& rhs) const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_);
Chris@16: 
Chris@16:       return value_ != rhs;
Chris@16:     }
Chris@16:     bool operator<(value_type const& rhs) const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_);
Chris@16: 
Chris@16:       return value_ < rhs;
Chris@16:     }
Chris@16:     bool operator<=(value_type const& rhs) const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_);
Chris@16: 
Chris@16:       return value_ <= rhs;
Chris@16:     }
Chris@16:     bool operator>(value_type const& rhs) const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_);
Chris@16: 
Chris@16:       return value_ > rhs;
Chris@16:     }
Chris@16:     bool operator>=(value_type const& rhs) const
Chris@16:     {
Chris@16:       unique_lock<mutex_type> lk1(mtx_);
Chris@16: 
Chris@16:       return value_ >= rhs;
Chris@16:     }
Chris@16: 
Chris@16:   };
Chris@16: 
Chris@16:   // Specialized algorithms
Chris@16:   /**
Chris@16:    *
Chris@16:    */
Chris@16:   template <typename T, typename L>
Chris@16:   inline void swap(synchronized_value<T,L> & lhs, synchronized_value<T,L> & rhs)
Chris@16:   {
Chris@16:     lhs.swap(rhs);
Chris@16:   }
Chris@16:   template <typename T, typename L>
Chris@16:   inline void swap(synchronized_value<T,L> & lhs, T & rhs)
Chris@16:   {
Chris@16:     lhs.swap(rhs);
Chris@16:   }
Chris@16:   template <typename T, typename L>
Chris@16:   inline void swap(T & lhs, synchronized_value<T,L> & rhs)
Chris@16:   {
Chris@16:     rhs.swap(lhs);
Chris@16:   }
Chris@16: 
Chris@16:   //Hash support
Chris@16: 
Chris@16: //  template <class T> struct hash;
Chris@16: //  template <typename T, typename L>
Chris@16: //  struct hash<synchronized_value<T,L> >;
Chris@16: 
Chris@16:   // Comparison with T
Chris@16:   template <typename T, typename L>
Chris@16:   bool operator!=(synchronized_value<T,L> const&lhs, synchronized_value<T,L> const& rhs)
Chris@16:   {
Chris@16:     return ! (lhs==rhs);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename T, typename L>
Chris@16:   bool operator==(T const& lhs, synchronized_value<T,L> const&rhs)
Chris@16:   {
Chris@16:     return rhs==lhs;
Chris@16:   }
Chris@16:   template <typename T, typename L>
Chris@16:   bool operator!=(T const& lhs, synchronized_value<T,L> const&rhs)
Chris@16:   {
Chris@16:     return rhs!=lhs;
Chris@16:   }
Chris@16:   template <typename T, typename L>
Chris@16:   bool operator<(T const& lhs, synchronized_value<T,L> const&rhs)
Chris@16:   {
Chris@16:     return rhs>=lhs;
Chris@16:   }
Chris@16:   template <typename T, typename L>
Chris@16:   bool operator<=(T const& lhs, synchronized_value<T,L> const&rhs)
Chris@16:   {
Chris@16:     return rhs>lhs;
Chris@16:   }
Chris@16:   template <typename T, typename L>
Chris@16:   bool operator>(T const& lhs, synchronized_value<T,L> const&rhs)
Chris@16:   {
Chris@16:     return rhs<=lhs;
Chris@16:   }
Chris@16:   template <typename T, typename L>
Chris@16:   bool operator>=(T const& lhs, synchronized_value<T,L> const&rhs)
Chris@16:   {
Chris@16:     return rhs<lhs;
Chris@16:   }
Chris@16: 
Chris@16:   /**
Chris@16:    *
Chris@16:    */
Chris@16:   template <typename OStream, typename T, typename L>
Chris@16:   inline OStream& operator<<(OStream& os, synchronized_value<T,L> const& rhs)
Chris@16:   {
Chris@16:     rhs.save(os);
Chris@16:     return os;
Chris@16:   }
Chris@16:   template <typename IStream, typename T, typename L>
Chris@16:   inline IStream& operator>>(IStream& is, synchronized_value<T,L> const& rhs)
Chris@16:   {
Chris@16:     rhs.load(is);
Chris@16:     return is;
Chris@16:   }
Chris@16: 
Chris@16: #if ! defined(BOOST_THREAD_NO_SYNCHRONIZE)
Chris@16: #if ! defined BOOST_NO_CXX11_VARIADIC_TEMPLATES
Chris@16: 
Chris@16:   template <typename ...SV>
Chris@16:   std::tuple<typename synchronized_value_strict_lock_ptr<SV>::type ...> synchronize(SV& ...sv)
Chris@16:   {
Chris@16:     boost::lock(sv.mtx_ ...);
Chris@16:     typedef std::tuple<typename synchronized_value_strict_lock_ptr<SV>::type ...> t_type;
Chris@16: 
Chris@16:     return t_type(typename synchronized_value_strict_lock_ptr<SV>::type(sv.value_, sv.mtx_, adopt_lock) ...);
Chris@16:   }
Chris@16: #else
Chris@16: 
Chris@16:   template <typename SV1, typename SV2>
Chris@16:   std::tuple<
Chris@16:     typename synchronized_value_strict_lock_ptr<SV1>::type,
Chris@16:     typename synchronized_value_strict_lock_ptr<SV2>::type
Chris@16:   >
Chris@16:   synchronize(SV1& sv1, SV2& sv2)
Chris@16:   {
Chris@16:     boost::lock(sv1.mtx_, sv2.mtx_);
Chris@16:     typedef std::tuple<
Chris@16:         typename synchronized_value_strict_lock_ptr<SV1>::type,
Chris@16:         typename synchronized_value_strict_lock_ptr<SV2>::type
Chris@16:         > t_type;
Chris@16: 
Chris@16:     return t_type(
Chris@16:         typename synchronized_value_strict_lock_ptr<SV1>::type(sv1.value_, sv1.mtx_, adopt_lock),
Chris@16:         typename synchronized_value_strict_lock_ptr<SV2>::type(sv2.value_, sv2.mtx_, adopt_lock)
Chris@16:         );
Chris@16: 
Chris@16:   }
Chris@16:   template <typename SV1, typename SV2, typename SV3>
Chris@16:   std::tuple<
Chris@16:     typename synchronized_value_strict_lock_ptr<SV1>::type,
Chris@16:     typename synchronized_value_strict_lock_ptr<SV2>::type,
Chris@16:     typename synchronized_value_strict_lock_ptr<SV3>::type
Chris@16:   >
Chris@16:   synchronize(SV1& sv1, SV2& sv2, SV3& sv3)
Chris@16:   {
Chris@16:     boost::lock(sv1.mtx_, sv2.mtx_);
Chris@16:     typedef std::tuple<
Chris@16:         typename synchronized_value_strict_lock_ptr<SV1>::type,
Chris@16:         typename synchronized_value_strict_lock_ptr<SV2>::type,
Chris@16:         typename synchronized_value_strict_lock_ptr<SV3>::type
Chris@16:         > t_type;
Chris@16: 
Chris@16:     return t_type(
Chris@16:         typename synchronized_value_strict_lock_ptr<SV1>::type(sv1.value_, sv1.mtx_, adopt_lock),
Chris@16:         typename synchronized_value_strict_lock_ptr<SV2>::type(sv2.value_, sv2.mtx_, adopt_lock),
Chris@16:         typename synchronized_value_strict_lock_ptr<SV3>::type(sv3.value_, sv3.mtx_, adopt_lock)
Chris@16:         );
Chris@16: 
Chris@16:   }
Chris@16: #endif
Chris@16: #endif
Chris@16: }
Chris@16: 
Chris@16: #include <boost/config/abi_suffix.hpp>
Chris@16: 
Chris@16: #endif // header