ceph/src/boost/libs/thread/example/recursive_mutex.cpp

   1 // Copyright (C) 2001-2003
   2 // William E. Kempf
   3 //
   4 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
   5 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6
   7 #include <boost/thread/recursive_mutex.hpp>
   8 #include <boost/thread/thread.hpp>
   9 #include <iostream>
  10
  11 class counter
  12 {
  13 public:
  14     counter() : count(0) { }
  15
  16     int add(int val) {
  17         boost::unique_lock<boost::recursive_mutex> scoped_lock(mutex);
  18         count += val;
  19         return count;
  20     }
  21     int increment() {
  22         boost::unique_lock<boost::recursive_mutex> scoped_lock(mutex);
  23         return add(1);
  24     }
  25
  26 private:
  27     boost::recursive_mutex mutex;
  28     int count;
  29 };
  30
  31 counter c;
  32
  33 void change_count()
  34 {
  35     //std::cout << "count == " << c.increment() << std::endl;
  36 }
  37
  38 int main(int, char*[])
  39 {
  40     const int num_threads=4;
  41
  42     boost::thread_group threads;
  43     for (int i=0; i < num_threads; ++i)
  44         threads.create_thread(&change_count);
  45
  46     threads.join_all();
  47
  48     return 0;
  49 }