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// Copyright (C) 2010 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)
// bm.cpp
// g++ test.cpp -lboost_thread-mt && ./a.out
// the ration of XXX and YYY determines
// if this works or deadlocks
int XXX = 20;
int YYY = 10;
#include <boost/thread/thread_only.hpp>
#include <boost/thread/shared_mutex.hpp>
//#include <unistd.h>
#include <iostream>
#include <boost/detail/lightweight_test.hpp>
using namespace std;
//void sleepmillis(useconds_t miliis)
void sleepmillis(int miliis)
{
//usleep(miliis * 1000);
boost::this_thread::sleep(boost::posix_time::milliseconds(miliis));
}
void worker1(boost::shared_mutex * lk, int * x)
{
(*x)++; // 1
cout << "lock b try " << *x << endl;
while (1)
{
if (lk->timed_lock(boost::posix_time::milliseconds(XXX))) break;
sleepmillis(YYY);
}
cout << "lock b got " << *x << endl;
(*x)++; // 2
lk->unlock();
}
void worker2(boost::shared_mutex * lk, int * x)
{
cout << "lock c try" << endl;
lk->lock_shared();
(*x)++;
cout << "lock c got" << endl;
lk->unlock_shared();
cout << "lock c unlocked" << endl;
(*x)++;
}
int main()
{
// create
boost::shared_mutex* lk = new boost::shared_mutex();
// read lock
cout << "lock a" << endl;
lk->lock_shared();
int x1 = 0;
boost::thread t1(boost::bind(worker1, lk, &x1));
while (!x1)
;
BOOST_TEST(x1 == 1);
sleepmillis(500);
BOOST_TEST(x1 == 1);
int x2 = 0;
boost::thread t2(boost::bind(worker2, lk, &x2));
t2.join();
BOOST_TEST(x2 == 2);
lk->unlock_shared();
cout << "unlock a" << endl;
for (int i = 0; i < 2000; i++)
{
if (x1 == 2) break;
sleepmillis(10);
}
BOOST_TEST(x1 == 2);
t1.join();
delete lk;
return 0;
}
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