time_sequencer.h
Go to the documentation of this file.
00001 /*********************************************************************
00002 * Software License Agreement (BSD License)
00003 *
00004 *  Copyright (c) 2008, Willow Garage, Inc.
00005 *  All rights reserved.
00006 *
00007 *  Redistribution and use in source and binary forms, with or without
00008 *  modification, are permitted provided that the following conditions
00009 *  are met:
00010 *
00011 *   * Redistributions of source code must retain the above copyright
00012 *     notice, this list of conditions and the following disclaimer.
00013 *   * Redistributions in binary form must reproduce the above
00014 *     copyright notice, this list of conditions and the following
00015 *     disclaimer in the documentation and/or other materials provided
00016 *     with the distribution.
00017 *   * Neither the name of the Willow Garage nor the names of its
00018 *     contributors may be used to endorse or promote products derived
00019 *     from this software without specific prior written permission.
00020 *
00021 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
00022 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
00023 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
00024 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
00025 *  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
00026 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
00027 *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
00028 *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
00029 *  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
00030 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
00031 *  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
00032 *  POSSIBILITY OF SUCH DAMAGE.
00033 *********************************************************************/
00034 
00035 #ifndef MESSAGE_FILTERS_TIME_SEQUENCER_H
00036 #define MESSAGE_FILTERS_TIME_SEQUENCER_H
00037 
00038 #include <ros/ros.h>
00039 
00040 #include "connection.h"
00041 #include "simple_filter.h"
00042 
00043 namespace message_filters
00044 {
00045 
00074 template<class M>
00075 class TimeSequencer : public SimpleFilter<M>
00076 {
00077 public:
00078   typedef boost::shared_ptr<M const> MConstPtr;
00079   typedef ros::MessageEvent<M const> EventType;
00080 
00089   template<class F>
00090   TimeSequencer(F& f, ros::Duration delay, ros::Duration update_rate, uint32_t queue_size, ros::NodeHandle nh = ros::NodeHandle())
00091   : delay_(delay)
00092   , update_rate_(update_rate)
00093   , queue_size_(queue_size)
00094   , nh_(nh)
00095   {
00096     init();
00097     connectInput(f);
00098   }
00099 
00110   TimeSequencer(ros::Duration delay, ros::Duration update_rate, uint32_t queue_size, ros::NodeHandle nh = ros::NodeHandle())
00111   : delay_(delay)
00112   , update_rate_(update_rate)
00113   , queue_size_(queue_size)
00114   , nh_(nh)
00115   {
00116     init();
00117   }
00118 
00122   template<class F>
00123   void connectInput(F& f)
00124   {
00125     incoming_connection_.disconnect();
00126     incoming_connection_ = f.registerCallback(typename SimpleFilter<M>::EventCallback(boost::bind(&TimeSequencer::cb, this, _1)));
00127   }
00128 
00129   ~TimeSequencer()
00130   {
00131     update_timer_.stop();
00132     incoming_connection_.disconnect();
00133   }
00134 
00135   void add(const EventType& evt)
00136   {
00137     namespace mt = ros::message_traits;
00138 
00139     boost::mutex::scoped_lock lock(messages_mutex_);
00140     if (mt::TimeStamp<M>::value(*evt.getMessage()) < last_time_)
00141     {
00142       return;
00143     }
00144 
00145     messages_.insert(evt);
00146 
00147     if (queue_size_ != 0 && messages_.size() > queue_size_)
00148     {
00149       messages_.erase(*messages_.begin());
00150     }
00151   }
00152 
00156   void add(const MConstPtr& msg)
00157   {
00158     EventType evt(msg);
00159     add(evt);
00160   }
00161 
00162 private:
00163   class MessageSort
00164   {
00165   public:
00166     bool operator()(const EventType& lhs, const EventType& rhs) const
00167     {
00168       namespace mt = ros::message_traits;
00169       return mt::TimeStamp<M>::value(*lhs.getMessage()) < mt::TimeStamp<M>::value(*rhs.getMessage());
00170     }
00171   };
00172   typedef std::multiset<EventType, MessageSort> S_Message;
00173   typedef std::vector<EventType> V_Message;
00174 
00175   void cb(const EventType& evt)
00176   {
00177     add(evt);
00178   }
00179 
00180   void dispatch()
00181   {
00182     namespace mt = ros::message_traits;
00183 
00184     V_Message to_call;
00185 
00186     {
00187       boost::mutex::scoped_lock lock(messages_mutex_);
00188 
00189       while (!messages_.empty())
00190       {
00191         const EventType& e = *messages_.begin();
00192         ros::Time stamp = mt::TimeStamp<M>::value(*e.getMessage());
00193         if (stamp + delay_ <= ros::Time::now())
00194         {
00195           last_time_ = stamp;
00196           to_call.push_back(e);
00197           messages_.erase(messages_.begin());
00198         }
00199         else
00200         {
00201           break;
00202         }
00203       }
00204     }
00205 
00206     {
00207       typename V_Message::iterator it = to_call.begin();
00208       typename V_Message::iterator end = to_call.end();
00209       for (; it != end; ++it)
00210       {
00211         this->signalMessage(*it);
00212       }
00213     }
00214   }
00215 
00216   void update(const ros::TimerEvent&)
00217   {
00218     dispatch();
00219   }
00220 
00221   void init()
00222   {
00223     update_timer_ = nh_.createTimer(update_rate_, &TimeSequencer::update, this);
00224   }
00225 
00226   ros::Duration delay_;
00227   ros::Duration update_rate_;
00228   uint32_t queue_size_;
00229   ros::NodeHandle nh_;
00230 
00231   ros::Timer update_timer_;
00232 
00233   Connection incoming_connection_;
00234 
00235 
00236   S_Message messages_;
00237   boost::mutex messages_mutex_;
00238   ros::Time last_time_;
00239 };
00240 
00241 }
00242 
00243 #endif


message_filters
Author(s): Josh Faust, Vijay Pradeep
autogenerated on Tue Mar 7 2017 04:01:23