2010/7/28 Giovanni Piero Deretta <gpderetta@gmail.com>:
On Wed, Jul 28, 2010 at 2:44 PM, Philippe Vaucher <philippe.vaucher@gmail.com> wrote:
Hello,
I've made a thread_safe_ptr class available at http://codepad.org/PxDEGaFm
The idea is to use it like so:
std::string data = "Hello world;"; thread_safe_ptr<std::string> data_ptr(&data);
void thread1() { data_ptr->resize(3); }
void thread2() { *data_ptr = "yeah"; }
boost::thread t1(&thread1); boost::thread t2(&thread1); t1.join(); t2.join();
std::stack<int> deq = ...; thread_safe_ptr<std::stack<int> > data_ptr(&data);
int pop() { int my_top = data_ptr->top(); data_ptr->pop(); // will this pop my_top? return my_pop; }
Unfortunately the interface of a class must be designed to be threadsafe, you can't just bolt on thread safety by locking every member function. Such a wrapper might have some limited use, but it could lead to a false sense of security.
Just my 0.2 €
I was about to make the same comment, however I noticed there is a thread_safe_ptr::scoped_lock with pointer semantics for such occasions. I think this solution is nice and would happily see it as a part of boost smart pointer or thread libraries. int pop() { thread_safe_ptr< std::stack<int> >::scoped_lock lock(data_ptr); int my_top = lock->top(); lock->pop(); return my_pop; } Yours, Krzysztof Wrzalik