| 1 | // Copyright (C) 2013 Vicente Botet |
|---|---|
| 2 | // |
| 3 | // Distributed under the Boost Software License, Version 1.0. (See accompanying |
| 4 | // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| 5 | |
| 6 | // futtest.cpp |
| 7 | #include <iostream> |
| 8 | #define BOOST_THREAD_VERSION 4 |
| 9 | |
| 10 | #include <boost/thread/future.hpp> |
| 11 | #include <boost/thread/thread.hpp> |
| 12 | #include <boost/bind.hpp> |
| 13 | #include <boost/chrono.hpp> |
| 14 | #include <boost/shared_ptr.hpp> |
| 15 | #include <boost/scoped_ptr.hpp> |
| 16 | |
| 17 | typedef boost::shared_ptr< boost::promise<int> > IntPromise; |
| 18 | |
| 19 | void foo(IntPromise p) |
| 20 | { |
| 21 | std::cout << "foo"<< std::endl; |
| 22 | p->set_value(123); // This line locks the future's mutex, then calls the continuation with the mutex already locked. |
| 23 | } |
| 24 | |
| 25 | void bar(boost::future<int> fooResult) |
| 26 | { |
| 27 | try { |
| 28 | std::cout << "bar"<< std::endl; |
| 29 | int i = fooResult.get(); // Code hangs on this line (Due to future already being locked by the set_value call) |
| 30 | std::cout << "i: "<< i << std::endl; |
| 31 | } catch(...) { |
| 32 | std::cout << __FILE__ << ":"<< __LINE__ << std::endl; |
| 33 | } |
| 34 | } |
| 35 | |
| 36 | int main() |
| 37 | { |
| 38 | std::cout << __FILE__ << ":"<< __LINE__ << std::endl; |
| 39 | try { |
| 40 | IntPromise p(new boost::promise<int>()); |
| 41 | boost::thread t(boost::bind(f: foo, a1: p)); |
| 42 | boost::future<int> f1 = p->get_future(); |
| 43 | f1.then(policy: boost::launch::deferred, func: &bar); |
| 44 | t.join(); |
| 45 | } catch(...) { |
| 46 | return 1; |
| 47 | } |
| 48 | std::cout << __FILE__ << ":"<< __LINE__ << std::endl; |
| 49 | try { |
| 50 | IntPromise p(new boost::promise<int>()); |
| 51 | boost::thread t(boost::bind(f: foo, a1: p)); |
| 52 | boost::future<int> f1 = p->get_future(); |
| 53 | f1.then(policy: boost::launch::async, func: &bar); |
| 54 | t.join(); |
| 55 | } catch(...) { |
| 56 | return 2; |
| 57 | } |
| 58 | std::cout << __FILE__ << ":"<< __LINE__ << std::endl; |
| 59 | } |
| 60 | |
| 61 |