2 // Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS)
3 // Kompetenzzentrum fuer Satelitenkommunikation (SatCom)
4 // Stefan Bund <g0dil@berlios.de>
6 // This program is free software; you can redistribute it and/or modify
7 // it under the terms of the GNU General Public License as published by
8 // the Free Software Foundation; either version 2 of the License, or
9 // (at your option) any later version.
11 // This program is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // You should have received a copy of the GNU General Public License
17 // along with this program; if not, write to the
18 // Free Software Foundation, Inc.,
19 // 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
22 \brief Connectors public header */
24 /** \defgroup connectors Connector classes
26 A connector has two independent properties
27 \li it may be \e active or \e passive
28 \li it may be an \e input or an \e output
30 \e Active connectors are activated from within the module, \e passive connectors are signaled by
31 the external framework. \e Input modules receive packets, \e output modules send packets.
33 All passive connectors call some onRequest callback whenever I/O needs to be performed. All
34 input modules possess a packet queue.
36 We therefore have 4 connector types: senf::ppi::ActiveInput, senf::ppi::ActiveOutput,
37 senf::ppi::PassiveInput and senf::ppi::PassiveOutput.
40 #ifndef HH_Connectors_
41 #define HH_Connectors_ 1
45 #include <boost/utility.hpp>
46 #include <boost/scoped_ptr.hpp>
47 #include "Utils/SafeBool.hh"
48 #include "Packets/Packets.hh"
50 #include "detail/Callback.hh"
51 #include "Queueing.hh"
53 //#include "Connectors.mpp"
54 ///////////////////////////////hh.p////////////////////////////////////////
60 /** \brief Connector baseclass
62 This connector provides access to the generic connector facilities. This includes the
63 connection management (access to the connected peer) and the containment management (access
64 to the containing module)
70 Connector & peer() const; ///< Get peer connected to this connector
71 module::Module & module() const; ///< Get this connectors containing module
77 void connect(Connector & target);
80 void setModule(module::Module & module);
83 module::Module * module_;
85 friend class module::Module;
88 /** \brief Passive connector baseclass
90 A passive connector is a connector which is activated externally whenever an I/O request
91 occurs. Passive connectors are the origin of throttling notifications. Depending on the type
92 of connector (output or input) the respective throttling is called forward or backward
95 Passive connectors always handle two throttling states:
97 \li The \e native throttling state is set manually by the module. It is the throttling state
98 originating in the current module
99 \li The \e forwarded throttling state is the state as it is received by throttling
102 The accumulative throttling state is generated by combining all sub-states.
104 class PassiveConnector
105 : public virtual Connector
108 template <class Handler>
109 void onRequest(Handler handler);///< Register I/O event handler
110 /**< The registered handler will be called, whenever packets
111 arrive or should be generated by the module depending
112 on the connector type (input or output). The \a handler
113 argument is either an arbitrary callable object or it
114 is a pointer-to-member to a member of the class which
115 holds this input. In the second case, the pointer will
116 automatically be bound to the containing instance.
118 \param[in] handler Handler to call, whenever an I/O
119 operation is to be performed. */
122 bool throttled() const; ///< Get accumulative throttling state
123 bool nativeThrottled() const; ///< Get native throttling state
125 void throttle(); ///< Set native throttling
126 void unthrottle(); ///< Revoke native throttling
128 ActiveConnector & peer() const;
136 // Called by the routing to change the remote throttling state
137 void notifyThrottle(); ///< Forward a throttling notification to this connector
138 void notifyUnthrottle(); ///< Forward an unthrottling notification to this connector
140 // Internal members to emit throttling notifications
142 void emitUnthrottle();
144 // Called after unthrottling the connector
145 virtual void v_unthrottleEvent();
147 typedef detail::Callback<>::type Callback;
150 bool remoteThrottled_;
151 bool nativeThrottled_;
153 friend class senf::ppi::ForwardingRoute;
156 /** \brief Active connector baseclass
158 An active connector is a connector which emits I/O requests. Active connectors receive
159 throttling notifications. Depending on the type of connector (input or output) the
160 respective throttling is called forward or backward throttling.
162 Active connectors do not handle any throttling state, they just receive the
163 notifications. These notifications should then either be processed by the module or be
164 forwarded to other connectors.
166 class ActiveConnector
167 : public virtual Connector
169 typedef detail::Callback<>::type Callback;
171 template <class Handler>
172 void onThrottle(Handler handler); ///< Register throttle notification handler
173 /**< The handler register here will be called, whenever a
174 throttle notification comes in. The \a handler argument
175 is either an arbitrary callable object or it is a
176 pointer-to-member to a member of the class which holds
177 this input. In the second case, the pointer will
178 automatically be bound to the containing instance.
180 \param[in] handler Handler to call on throttle
184 template <class Handler>
185 void onUnthrottle(Handler handler); ///< Register unthrottle notification handler
186 /**< The handler register here will be called, whenever an
187 unthrottle notification comes in. The \a handler
188 argument is either an arbitrary callable object or it
189 is a pointer-to-member to a member of the class which
190 holds this input. In the second case, the pointer will
191 automatically be bound to the containing instance.
193 \param[in] handle Handler to call on unthrottle
197 PassiveConnector & peer() const;
203 // called by the peer() to forward throttling notifications
204 void notifyThrottle();
205 void notifyUnthrottle();
207 // called by ForwardingRoute to register a new route
208 void registerRoute(ForwardingRoute & route);
210 Callback throttleCallback_;
211 Callback unthrottleCallback_;
213 typedef std::vector<ForwardingRoute*> NotifyRoutes;
214 NotifyRoutes notifyRoutes_;
216 friend class senf::ppi::ForwardingRoute;
217 friend class PassiveConnector;
220 /** \brief Input connector baseclass
222 An input connector receives packets. It may be either an ActiveConnector or a
223 PassiveConnector. An input connector contains a packet queue. This queue enables processing
224 packets in batches or generating multiple output packets from a single input packet. The
225 queues have the potential to greatly simplify the module implementations.
227 \implementation Which container to use?
228 \li list has good insertion and deletion properties on both ends but it costs a dynamic
229 memory allocation for every insertion. A very good property is, that iterators stay
230 valid across insertions/deletions
231 \li vector is fast and has good amortized dynamic allocation properties. However, it is
232 quite unusable as a queue
233 \li deque has comparable dynamic allocation properties as vector but also has good
234 insertion/removal properties on both ends.
236 So probably we will use a deque. I'd like a container which keeps iterators intact on
237 isertion/deletion but I believe that list is just to expensive since every packet will
238 be added to the queue before it can be processed.
241 : public virtual Connector
243 typedef std::deque<Packet> Queue;
245 typedef Queue::const_iterator queue_iterator; ///< Iterator type of the embedded queue
246 typedef Queue::size_type size_type; ///< Unsigned type for counting queue elements
248 Packet operator()(); ///< Get a packet
249 /**< This member is the primary method to access received
250 data. On passive connectors, this operator will just
251 dequeue a packet from the packet queue. If the
252 connector is active, the connector will request new
253 packets from the connected module. If the packet
254 request cannot be fulfilled, this is considered to be a
255 logic error in the module implementation and an
256 exception is raised. */
258 OutputConnector & peer() const;
260 queue_iterator begin() const; ///< Access queue begin (head)
261 queue_iterator end() const; ///< Access queue past-the-end (tail)
262 Packet peek() const; ///< Return head element from the queue
264 size_type queueSize() const; ///< Return number of elements in the queue
265 bool empty() const; ///< Return queueSize() == 0
271 void enqueue(Packet p);
273 virtual void v_requestEvent();
274 virtual void v_enqueueEvent();
275 virtual void v_dequeueEvent();
279 friend class OutputConnector;
282 /** \brief Output connector baseclass
284 An output connector sends out packets. It may be either an ActiveConnector or a
285 PassiveConnector. An output connector does \e not have an built-in queueing, it relies on
286 the queueing of the connected input.
288 class OutputConnector
289 : public virtual Connector
292 void operator()(Packet p); ///< Send out a packet
294 InputConnector & peer() const;
301 ///\addtogroup connectors
303 /** \brief Combination of PassiveConnector and InputConnector
305 The PassiveInput automatically controls the connectors throttling state using a queueing
306 discipline. The standard queueing discipline is ThresholdQueueing, which throttles the
307 connection whenever the queue length reaches the high threshold and unthrottles the
308 connection when the queue reaches the low threshold. The default queueing discipline is
309 <tt>ThresholdQueueing(1,0)</tt> which will throttle the input whenever the queue is
313 : public PassiveConnector, public InputConnector,
314 public SafeBool<PassiveInput>
319 ActiveOutput & peer() const;
321 bool boolean_test() const;
323 template <class QDisc>
324 void qdisc(QDisc const & disc); ///< Change the queueing discipline
325 /**< The queueing discipline is a class which provides the
326 QueueingDiscipline interface.
328 \param[in] disc New queueing discipline */
331 void v_enqueueEvent();
332 void v_dequeueEvent();
333 void v_unthrottleEvent();
335 boost::scoped_ptr<QueueingDiscipline> qdisc_;
338 /** \brief Combination of PassiveConnector and OutputConnector
341 : public PassiveConnector, public OutputConnector,
342 public SafeBool<PassiveOutput>
345 ActiveInput & peer() const;
347 bool boolean_test() const;
349 void connect(ActiveInput & target);
351 friend class ActiveInput;
354 /** \brief Combination of ActiveConnector and InputConnector
357 : public ActiveConnector, public InputConnector,
358 public SafeBool<ActiveInput>
361 PassiveOutput & peer() const;
363 bool boolean_test() const;
365 void request(); ///< request more packets without dequeuing any packet
368 void v_requestEvent();
371 /** \brief Combination of ActiveConnector and OutputConnector
374 : public ActiveConnector, public OutputConnector,
375 public SafeBool<ActiveOutput>
378 PassiveInput & peer() const;
380 bool boolean_test() const;
382 void connect(PassiveInput & target);
389 ///////////////////////////////hh.e////////////////////////////////////////
390 #include "Connectors.cci"
391 //#include "Connectors.ct"
392 #include "Connectors.cti"
399 // c-file-style: "senf"
400 // indent-tabs-mode: nil
401 // ispell-local-dictionary: "american"
402 // compile-command: "scons -u test"
403 // comment-column: 40