| #ifndef PROTON_THREAD_SAFE_HPP |
| #define PROTON_THREAD_SAFE_HPP |
| |
| /* |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * |
| */ |
| |
| #include "./internal/config.hpp" |
| #include "./connection.hpp" |
| #include "./event_loop.hpp" |
| #include "./internal/object.hpp" |
| #include "./internal/type_traits.hpp" |
| |
| #include <functional> |
| |
| namespace proton { |
| |
| class connection; |
| class session; |
| class link; |
| class sender; |
| class receiver; |
| |
| namespace internal { |
| template <class T> struct endpoint_traits; |
| template<> struct endpoint_traits<connection> {}; |
| template<> struct endpoint_traits<session> {}; |
| template<> struct endpoint_traits<link> {}; |
| template<> struct endpoint_traits<sender> {}; |
| template<> struct endpoint_traits<receiver> {}; |
| } |
| |
| template <class T> class returned; |
| |
| /// **Experimental** - A thread-safe object wrapper. |
| /// |
| /// The proton::object subclasses (proton::connection, proton::sender etc.) are |
| /// reference-counted wrappers for C structs. They are not safe for concurrent use, |
| /// not even to copy or assign. |
| /// |
| /// A pointer to thread_safe<> can be used from any thread to get the |
| /// proton::event_loop for the object's connection. The object will not be |
| /// destroyed until the thread_safe<> is deleted. You can use std::shared_ptr, |
| /// std::unique_ptr or any other memory management technique to manage the |
| /// thread_safe<>. |
| /// |
| /// Use make_thread_safe(), make_shared_thread_safe(), make_unique_thread_safe() to |
| /// create a thread_safe<> |
| /// |
| /// @see @ref mt_page |
| template <class T> |
| class thread_safe : private internal::pn_ptr_base, private internal::endpoint_traits<T> { |
| typedef typename T::pn_type pn_type; |
| |
| struct inject_decref : public void_function0 { |
| pn_type* ptr_; |
| inject_decref(pn_type* p) : ptr_(p) {} |
| void operator()() PN_CPP_OVERRIDE { decref(ptr_); delete this; } |
| }; |
| |
| public: |
| /// @cond INTERNAL |
| static void operator delete(void*) {} |
| /// @endcond |
| |
| ~thread_safe() { |
| if (ptr()) { |
| if (event_loop()) { |
| #if PN_CPP_HAS_CPP11 |
| event_loop()->inject(std::bind(&decref, ptr())); |
| #else |
| event_loop()->inject(*new inject_decref(ptr())); |
| #endif |
| } else { |
| decref(ptr()); |
| } |
| } |
| } |
| |
| /// Get the event loop for this object. |
| class event_loop* event_loop() { return event_loop::get(ptr()); } |
| |
| /// Get the thread-unsafe proton object wrapped by this thread_safe<T> |
| T unsafe() { return T(ptr()); } |
| |
| private: |
| static thread_safe* create(const T& obj) { return new (obj.pn_object()) thread_safe(); } |
| static void* operator new(size_t, pn_type* p) { return p; } |
| static void operator delete(void*, pn_type*) {} |
| thread_safe() { incref(ptr()); } |
| pn_type* ptr() { return reinterpret_cast<pn_type*>(this); } |
| |
| |
| // Non-copyable. |
| thread_safe(const thread_safe&); |
| thread_safe& operator=(const thread_safe&); |
| |
| /// @cond INTERNAL |
| friend class returned<T>; |
| /// @endcond |
| }; |
| |
| // return value for functions returning a thread_safe<> object. |
| // |
| // Temporary return value only, you should release() to get a plain pointer or |
| // assign to a smart pointer type. |
| template <class T> |
| class returned : private internal::endpoint_traits<T> |
| { |
| public: |
| /// Take ownership |
| explicit returned(thread_safe<T>* p) : ptr_(p) {} |
| /// Create an owned thread_safe<T> |
| explicit returned(const T& obj) : ptr_(thread_safe<T>::create(obj)) {} |
| /// Transfer ownership. |
| /// Use the same "cheat" as std::auto_ptr, calls x.release() even though x is const. |
| returned(const returned& x) : ptr_(const_cast<returned&>(x).release()) {} |
| /// Delete if still owned. |
| ~returned() { if (ptr_) delete ptr_; } |
| |
| /// Release ownership. |
| thread_safe<T>* release() const { thread_safe<T>* p = ptr_; ptr_ = 0; return p; } |
| |
| /// Get the raw pointer, caller must not delete. |
| thread_safe<T>* get() const { return ptr_; } |
| |
| /// Implicit conversion to target, usable only in a safe context. |
| operator T() { return ptr_->unsafe(); } |
| |
| #if PN_CPP_HAS_CPP11 |
| /// Release to a std::shared_ptr |
| operator std::shared_ptr<thread_safe<T> >() { |
| return std::shared_ptr<thread_safe<T> >(release()); |
| } |
| |
| /// Release to a std::unique_ptr |
| operator std::unique_ptr<thread_safe<T> >() { |
| return std::unique_ptr<thread_safe<T> >(release()); |
| } |
| #endif |
| |
| private: |
| void operator=(const returned&); |
| mutable thread_safe<T>* ptr_; |
| }; |
| |
| /// Make a thread-safe wrapper for `obj`. |
| template <class T> returned<T> make_thread_safe(const T& obj) { return returned<T>(obj); } |
| |
| #if PN_CPP_HAS_CPP11 |
| template <class T> std::shared_ptr<thread_safe<T> > make_shared_thread_safe(const T& obj) { |
| return make_thread_safe(obj); |
| } |
| template <class T> std::unique_ptr<thread_safe<T> > make_unique_thread_safe(const T& obj) { |
| return make_thread_safe(obj); |
| } |
| #endif |
| |
| } // proton |
| |
| #endif // PROTON_THREAD_SAFE_HPP |