ceph/src/boost/libs/thread/test/test_7755.cpp

   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 ////////////////////////////////////////////
   7
   8 //#define BOOST_THREAD_PROVIDES_GENERIC_SHARED_MUTEX_ON_WIN
   9 #include <iostream>
  10 #include <boost/thread/thread_only.hpp>
  11 #include <boost/thread/shared_mutex.hpp>
  12 // shared_mutex_deadlock.cpp : Defines the entry point for the console application.
  13 //
  14
  15
  16 boost::shared_mutex mutex;
  17
  18 void thread2_func()
  19 {
  20   int i (0);
  21   while (true)
  22   {
  23     if (mutex.timed_lock(boost::posix_time::milliseconds(500)))
  24     {
  25       std::cout << "Unique lock acquired" << std::endl
  26         << "Test successful" << std::endl;
  27       mutex.unlock();
  28       break;
  29     }
  30     ++i;
  31     if (i == 100)
  32     {
  33       std::cout << "Test failed. App is deadlocked" << std::endl;
  34       break;
  35     }
  36     boost::this_thread::sleep(boost::posix_time::seconds(1));
  37   }
  38 }
  39
  40 void thread3_func()
  41 {
  42   boost::shared_lock<boost::shared_mutex> lock (mutex);
  43   std::cout << "Shared lock acquired" << std::endl
  44         << "Test successful" << std::endl;
  45 }
  46
  47 void thread3_func_workaround()
  48 {
  49   while (true)
  50   {
  51     if (mutex.timed_lock_shared(boost::posix_time::milliseconds(200)))
  52     {
  53       std::cout << "Shared lock acquired" << std::endl
  54         << "Test successful" << std::endl;
  55       mutex.unlock_shared();
  56       break;
  57     }
  58     boost::this_thread::sleep(boost::posix_time::milliseconds(100));
  59   }
  60 }
  61
  62 int main()
  63 {
  64   std::cout << "Starting" << std::endl;
  65
  66   // 1 - lock the mutex
  67   boost::shared_lock<boost::shared_mutex> lock (mutex);
  68
  69   // 2 - start thread#2
  70   boost::thread thread2(&thread2_func);
  71
  72   // 3 - sleep
  73   boost::this_thread::sleep(boost::posix_time::milliseconds(10));
  74
  75   std::cout << "Thread#2 is waiting" << std::endl;
  76
  77   // - start thread3
  78   boost::thread thread3(&thread3_func);
  79   //boost::thread thread3(&thread3_func_workaround);
  80
  81   std::cout << "Thread#3 is started and blocked. It never will waked" << std::endl;
  82
  83   thread3.join(); // will never return
  84
  85   lock.unlock(); // release shared ownership. thread#2 will take unique ownership
  86
  87   thread2.join();
  88
  89   std::cout << "Finished" << std::endl;
  90   return 0;
  91 }
  92
  93
  94