// Copyright (C) 2013 Vicente Botet

//

// 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)

// futtest.cpp

#include <iostream>

#define BOOST_THREAD_VERSION 4

#include <boost/thread/future.hpp>

#include <boost/thread/thread.hpp>

#include <boost/bind.hpp>

#include <boost/chrono.hpp>

#include <boost/shared_ptr.hpp>

#include <boost/scoped_ptr.hpp>

typedef boost::shared_ptr< boost::promise<int> > IntPromise;

void foo(IntPromise p)

{

std::cout << "foo" << std::endl;

p->set_value(123); // This line locks the future's mutex, then calls the continuation with the mutex already locked.

}

void bar(boost::future<int> fooResult)

{

try {

std::cout << "bar" << std::endl;

int i = fooResult.get(); // Code hangs on this line (Due to future already being locked by the set_value call)

std::cout << "i: " << i << std::endl;

} catch(...) {

std::cout << __FILE__ << ":" << __LINE__ << std::endl;

}

}

int main()

{

std::cout << __FILE__ << ":" << __LINE__ << std::endl;

try {

IntPromise p(new boost::promise<int>());

boost::thread t(boost::bind(foo, p));

boost::future<int> f1 = p->get_future();

f1.then(boost::launch::deferred, &bar);

t.join();

} catch(...) {

return 1;

}

std::cout << __FILE__ << ":" << __LINE__ << std::endl;

try {

IntPromise p(new boost::promise<int>());

boost::thread t(boost::bind(foo, p));

boost::future<int> f1 = p->get_future();

f1.then(boost::launch::async, &bar);

t.join();

} catch(...) {

return 2;

}

std::cout << __FILE__ << ":" << __LINE__ << std::endl;

}