00001 /********************************************************************* 00002 * 00003 * Software License Agreement (BSD License) 00004 * 00005 * Copyright (c) 2009, Willow Garage, Inc. 00006 * All rights reserved. 00007 * 00008 * Redistribution and use in source and binary forms, with or without 00009 * modification, are permitted provided that the following conditions 00010 * are met: 00011 * 00012 * * Redistributions of source code must retain the above copyright 00013 * notice, this list of conditions and the following disclaimer. 00014 * * Redistributions in binary form must reproduce the above 00015 * copyright notice, this list of conditions and the following 00016 * disclaimer in the documentation and/or other materials provided 00017 * with the distribution. 00018 * * Neither the name of Willow Garage, Inc. nor the names of its 00019 * contributors may be used to endorse or promote products derived 00020 * from this software without specific prior written permission. 00021 * 00022 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 00023 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 00024 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 00025 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 00026 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 00027 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 00028 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 00029 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 00030 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 00031 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 00032 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 00033 * POSSIBILITY OF SUCH DAMAGE. 00034 * 00035 * Author: Eitan Marder-Eppstein 00036 *********************************************************************/ 00037 #ifndef ACTIONLIB__DESTRUCTION_GUARD_H_ 00038 #define ACTIONLIB__DESTRUCTION_GUARD_H_ 00039 00040 #include <boost/thread/condition.hpp> 00041 #include <boost/thread/mutex.hpp> 00042 00043 namespace actionlib 00044 { 00049 class DestructionGuard 00050 { 00051 public: 00055 DestructionGuard() 00056 : use_count_(0), destructing_(false) {} 00057 void destruct() 00058 { 00059 boost::mutex::scoped_lock lock(mutex_); 00060 destructing_ = true; 00061 while (use_count_ > 0) { 00062 count_condition_.timed_wait(lock, boost::posix_time::milliseconds(1000)); 00063 } 00064 } 00065 00070 bool tryProtect() 00071 { 00072 boost::mutex::scoped_lock lock(mutex_); 00073 if (destructing_) { 00074 return false; 00075 } 00076 use_count_++; 00077 return true; 00078 } 00079 00083 void unprotect() 00084 { 00085 boost::mutex::scoped_lock lock(mutex_); 00086 use_count_--; 00087 } 00088 00093 class ScopedProtector 00094 { 00095 public: 00100 ScopedProtector(DestructionGuard & guard) 00101 : guard_(guard), protected_(false) 00102 { 00103 protected_ = guard_.tryProtect(); 00104 } 00105 00110 bool isProtected() 00111 { 00112 return protected_; 00113 } 00114 00118 ~ScopedProtector() 00119 { 00120 if (protected_) { 00121 guard_.unprotect(); 00122 } 00123 } 00124 00125 private: 00126 DestructionGuard & guard_; 00127 bool protected_; 00128 }; 00129 00130 private: 00131 boost::mutex mutex_; 00132 int use_count_; 00133 bool destructing_; 00134 boost::condition count_condition_; 00135 }; 00136 00137 } // namespace actionlib 00138 #endif // ACTIONLIB__DESTRUCTION_GUARD_H_