4 // Fraunhofer Institute for Open Communication Systems (FOKUS)
5 // Competence Center NETwork research (NET), St. Augustin, GERMANY
6 // Stefan Bund <g0dil@berlios.de>
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 2 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the
20 // Free Software Foundation, Inc.,
21 // 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 \brief Connectors public header */
26 #ifndef HH_SENF_PPI_Connectors_
27 #define HH_SENF_PPI_Connectors_ 1
31 #include <boost/utility.hpp>
32 #include <boost/scoped_ptr.hpp>
33 #include "../Utils/safe_bool.hh"
34 #include "../Utils/Exception.hh"
35 #include "../Packets/Packets.hh"
37 #include "detail/Callback.hh"
38 #include "Queueing.hh"
39 #include "ModuleManager.hh"
41 //#include "Connectors.mpp"
42 ///////////////////////////////hh.p////////////////////////////////////////
48 /** \namespace senf::ppi::connector
49 \brief Connector classes
51 A connector has three independent properties
52 \li it may be \e active or \e passive
53 \li it may be an \e input or an \e output
54 \li it has an (optional) packet type
56 \e Active connectors are activated from within the module, \e passive connectors are
57 signaled by the external framework. \e Input connectors receive packets, \e output
58 connectors send packets.
60 All passive connectors call some onRequest callback whenever I/O needs to be performed. All
61 input connectors possess a packet queue.
63 We therefore have 4 connector types each of which is parameterized by the type of packet
64 traversing the connector:
65 \li senf::ppi::connector::ActiveInput
66 \li senf::ppi::connector::ActiveOutput
67 \li senf::ppi::connector::PassiveInput
68 \li senf::ppi::connector::PassiveOutput.
70 Connectors are declared as module data members and are then externally connected to other
73 The connectors each take an optional template argument. If this argument is specified, it
74 must be the type of packet expected or sent on this connector. If it is not specified,
75 packets will be passed using the generic Packet handle.
78 class IpFilter : public senf::ppi::module::Module
80 SENF_PPI_MODULE(SomeModule);
83 senf::ppi::connector::ActiveInput<senf::EthernetPacket> input;
84 senf::ppi::connector::PassiveOutput<senf::IpPacket> output;
88 input.onRequest(&IpFilter::onRequest);
93 // 'input()' will return a senf::EthernetPacket packet handle
94 try { output( input().find<senf::IpPacket>() ); }
95 catch (senf::InvalidPacketChainException & ex) { ; }
101 \section ppi_jacks Jacks
103 A Jack is a packet type aware and possibly packet type converting reference to an arbitrary
104 connector of the same type. Jacks are used in groups to indirectly declare the input's and
111 senf::ppi::module::PassiveQueue queue;
112 senf::ppi::module::RateAnalyzer analyzer;
115 senf::ppi::connector::ActiveInputJack<senf::EthernetPacket> input;
116 senf::ppi::connector::ActiveOutputJack<senf::EthernetPacket> output;
119 : queue (), analyzer (), input (queue.input), output (analyzer.output)
121 senf::ppi::connect(queue, analyzer);
126 The jacks are initialized by passing an arbitrary compatible connector to the jack
127 constructor. A connector is compatible, if
128 \li It has the same input/output active/passive specification
129 \li Either the Jack or the Connector are generic (senf::Packet) or Jack and Connector have
132 Jacks can be used wherever connectors may be used. Jacks may be defined anywhere, not only
133 in modules. It is however important to ensure that the lifetime of the jack does not exceed
134 the lifetime of the referenced connector.
137 senf::ppi::module::Module \n
138 senf::ppi::connect() \n
142 /** \brief Incompatible connectors connected
144 This exception is thrown, when two incompatible connectors are connected. This happens if
145 both connectors of a senf::ppi::connect() statement declare a packet type (the connector
146 template argument) but they don't declare the same packet type.
148 You need to ensure, that both connectors use the same packet type.
150 \see senf::ppi::connect()
152 struct IncompatibleConnectorsException : public senf::Exception
153 { IncompatibleConnectorsException() : senf::Exception("Incompatible connectors") {} };
155 /** \brief Connector base-class
157 This connector provides access to the generic connector facilities. This includes the
158 connection management (access to the connected peer) and the containment management (access
159 to the containing module)
162 : ModuleManager::Initializable, boost::noncopyable
164 SENF_LOG_CLASS_AREA();
165 SENF_LOG_DEFAULT_LEVEL(senf::log::NOTICE);
167 Connector & peer() const; ///< Get peer connected to this connector
168 module::Module & module() const; ///< Get this connectors containing module
170 bool connected() const; ///< \c true, if connector connected, \c false otherwise
172 void disconnect(); ///< Disconnect connector from peer
174 enum TraceState { NO_TRACING, TRACE_IDS, TRACE_CONTENTS };
176 static void tracing(TraceState state);
177 static TraceState tracing();
181 virtual ~Connector();
183 void connect(Connector & target);
185 void trace(Packet const & p, char const * label);
188 virtual std::type_info const & packetTypeID();
190 void setModule(module::Module & module);
193 module::Module * module_;
195 static TraceState traceState_;
197 friend class module::Module;
200 /** \brief Passive connector base-class
202 A passive connector is a connector which is activated externally whenever an I/O request
203 occurs. Passive connectors are the origin of throttling notifications. Depending on the type
204 of connector (output or input) the respective throttling is called forward or backward
207 Passive connectors always handle two throttling states:
209 - The \e native throttling state is set manually by the module. It is the throttling state
210 originating in the current module
211 - The \e forwarded throttling state is the state as it is received by throttling
214 The accumulative throttling state is generated by combining all sub-states.
216 class PassiveConnector
217 : public virtual Connector
220 template <class Handler>
221 void onRequest(Handler handler);///< Register I/O event handler
222 /**< The registered handler will be called, whenever packets
223 arrive or should be generated by the module depending
224 on the connector type (input or output). The \a handler
225 argument is either an arbitrary callable object or it
226 is a pointer-to-member to a member of the class which
227 holds this input. In the second case, the pointer will
228 automatically be bound to the containing instance.
230 \param[in] handler Handler to call, whenever an I/O
231 operation is to be performed. */
234 bool throttled() const; ///< Get accumulative throttling state
235 bool nativeThrottled() const; ///< Get native throttling state
237 void throttle(); ///< Set native throttling
238 void unthrottle(); ///< Revoke native throttling
240 ActiveConnector & peer() const;
248 virtual void v_init();
250 // Called by the routing to change the remote throttling state
251 void notifyThrottle(); ///< Forward a throttle notification to this connector
252 void notifyUnthrottle(); ///< Forward an unthrottle notification to this connector
254 // Internal members to emit throttling notifications
256 void emitUnthrottle();
258 // Called after unthrottling the connector
259 virtual void v_unthrottleEvent();
261 // called by ForwardingRoute to register a new route
262 void registerRoute(ForwardingRoute & route);
264 typedef ppi::detail::Callback<>::type Callback;
267 bool remoteThrottled_;
268 bool nativeThrottled_;
270 typedef std::vector<ForwardingRoute*> Routes;
273 friend class senf::ppi::ForwardingRoute;
276 /** \brief Active connector base-class
278 An active connector is a connector which emits I/O requests. Active connectors receive
279 throttling notifications. Depending on the type of connector (input or output) the
280 respective throttling is called forward or backward throttling.
282 Active connectors do not handle any throttling state, they just receive the
283 notifications. These notifications should then either be processed by the module or be
284 forwarded to other connectors.
286 class ActiveConnector
287 : public virtual Connector
289 typedef ppi::detail::Callback<>::type Callback;
291 template <class Handler>
292 void onThrottle(Handler handler); ///< Register throttle notification handler
293 /**< The handler register here will be called, whenever a
294 throttle notification comes in. The \a handler argument
295 is either an arbitrary callable object or it is a
296 pointer-to-member to a member of the class which holds
297 this input. In the second case, the pointer will
298 automatically be bound to the containing instance.
300 \param[in] handler Handler to call on throttle
302 void onThrottle(); ///< Clear throttle notification handler
304 template <class Handler>
305 void onUnthrottle(Handler handler); ///< Register unthrottle notification handler
306 /**< The handler register here will be called, whenever an
307 unthrottle notification comes in. The \a handler
308 argument is either an arbitrary callable object or it
309 is a pointer-to-member to a member of the class which
310 holds this input. In the second case, the pointer will
311 automatically be bound to the containing instance.
313 \param[in] handler Handler to call on unthrottle
315 void onUnthrottle(); ///< Clear unthrottle notification handler
317 bool throttled() const; ///< \c true, if peer() is throttled
319 PassiveConnector & peer() const;
325 virtual void v_init();
327 // called by the peer() to forward throttling notifications
328 void notifyThrottle();
329 void notifyUnthrottle();
331 // called by ForwardingRoute to register a new route
332 void registerRoute(ForwardingRoute & route);
334 Callback throttleCallback_;
335 Callback unthrottleCallback_;
337 typedef std::vector<ForwardingRoute*> NotifyRoutes;
338 NotifyRoutes notifyRoutes_;
342 friend class senf::ppi::ForwardingRoute;
343 friend class PassiveConnector;
346 /** \brief Input connector base-class
348 An input connector receives packets. It may be either an ActiveConnector or a
349 PassiveConnector. An input connector contains a packet queue. This queue enables processing
350 packets in batches or generating multiple output packets from a single input packet. The
351 queues have the potential to greatly simplify the module implementations.
353 \implementation Which container to use?
354 \li list has good insertion and deletion properties on both ends but it costs a dynamic
355 memory allocation for every insertion. A very good property is, that iterators stay
356 valid across insertions/deletions
357 \li vector is fast and has good amortized dynamic allocation properties. However, it is
358 quite unusable as a queue
359 \li deque has comparable dynamic allocation properties as vector but also has good
360 insertion/removal properties on both ends.
362 So probably we will use a deque. I'd like a container which keeps iterators intact on
363 insertion/deletion but I believe that list is just to expensive since every packet will
364 be added to the queue before it can be processed.
367 : public virtual Connector
369 typedef std::deque<Packet> Queue;
371 typedef Queue::const_iterator queue_iterator; ///< Iterator type of the embedded queue
372 typedef Queue::size_type size_type; ///< Unsigned type for counting queue elements
375 Packet operator()(); ///< Get a packet
376 /**< This member is the primary method to access received
377 data. On passive connectors, this operator will just
378 dequeue a packet from the packet queue. If the
379 connector is active, the connector will request new
380 packets from the connected module. If the packet
381 request cannot be fulfilled, this is considered to be a
382 logic error in the module implementation and an
383 exception is raised. */
385 Packet read(); ///< Alias for operator()()
387 OutputConnector & peer() const;
389 queue_iterator begin() const; ///< Access queue begin (head)
390 queue_iterator end() const; ///< Access queue past-the-end (tail)
391 Packet peek() const; ///< Return head element from the queue
393 size_type queueSize() const; ///< Return number of elements in the queue
394 bool empty() const; ///< Return queueSize() == 0
400 void enqueue(Packet const & p);
402 virtual void v_requestEvent();
403 virtual void v_enqueueEvent();
404 virtual void v_dequeueEvent();
408 friend class OutputConnector;
411 /** \brief Output connector base-class
413 An output connector sends out packets. It may be either an ActiveConnector or a
414 PassiveConnector. An output connector does \e not have an built-in queueing, it relies on
415 the queueing of the connected input.
417 class OutputConnector
418 : public virtual Connector
421 void operator()(Packet const & p); ///< Send out a packet
423 void write(Packet const & p); ///< Alias for operator()(Packet p)
425 InputConnector & peer() const;
431 /** \brief Combination of PassiveConnector and InputConnector
433 The GenericPassiveInput automatically controls the connectors throttling state using a
434 queueing discipline. The standard queueing discipline is ThresholdQueueing, which throttles
435 the connection whenever the queue length reaches the high threshold and unthrottles the
436 connection when the queue reaches the low threshold. The default queueing discipline is
437 <tt>ThresholdQueueing(1,0)</tt> which will throttle the input whenever the queue is
440 class GenericPassiveInput
441 : public PassiveConnector, public InputConnector,
442 public safe_bool<GenericPassiveInput>
445 GenericActiveOutput & peer() const;
447 bool boolean_test() const; ///< \c true, if ! empty()
449 template <class QDisc>
450 void qdisc(QDisc const & disc); ///< Change the queueing discipline
451 /**< The queueing discipline is a class which provides the
452 QueueingDiscipline interface.
454 \param[in] disc New queueing discipline */
457 GenericPassiveInput();
460 void v_enqueueEvent();
461 void v_dequeueEvent();
462 void v_unthrottleEvent();
464 boost::scoped_ptr<QueueingDiscipline> qdisc_;
467 /** \brief Combination of PassiveConnector and OutputConnector
469 class GenericPassiveOutput
470 : public PassiveConnector, public OutputConnector,
471 public safe_bool<GenericPassiveOutput>
474 GenericActiveInput & peer() const;
476 bool boolean_test() const; ///< Always \c true
478 void connect(GenericActiveInput & target); ///< Internal: Use senf::ppi::connect() instead
480 friend class GenericActiveInput;
483 GenericPassiveOutput();
487 /** \brief Combination of ActiveConnector and InputConnector
489 class GenericActiveInput
490 : public ActiveConnector, public InputConnector,
491 public safe_bool<GenericActiveInput>
494 GenericPassiveOutput & peer() const;
496 bool boolean_test() const; ///< \c true, if ! empty() or ! throttled()
498 void request(); ///< request more packets without dequeuing any packet
501 GenericActiveInput();
504 void v_requestEvent();
507 /** \brief Combination of ActiveConnector and OutputConnector
509 class GenericActiveOutput
510 : public ActiveConnector, public OutputConnector,
511 public safe_bool<GenericActiveOutput>
514 GenericPassiveInput & peer() const;
516 bool boolean_test() const; ///< \c true if peer() is ! throttled()
518 void connect(GenericPassiveInput & target); ///< Internal: Use senf::ppi::connect() instead
521 GenericActiveOutput();
527 # define TypedConnector_Input read
528 # define TypedConnector_Output write
529 # define TypedConnector(pType, dir) \
530 template <class PacketType> \
532 : public Generic ## pType ## dir, \
533 private detail::Typed ## dir ## Mixin<pType ## dir <PacketType>, PacketType> \
535 typedef detail::Typed ## dir ## Mixin<pType ## dir <PacketType>, PacketType> mixin; \
537 using mixin::operator(); \
538 using mixin::TypedConnector_ ## dir ; \
540 virtual std::type_info const & packetTypeID() \
541 { return typeid(typename PacketType::type); } \
542 friend class detail::Typed ## dir ## Mixin<pType ## dir <PacketType>, PacketType>; \
545 class pType ## dir <Packet> : public Generic ## pType ## dir \
548 TypedConnector( Passive, Input );
549 TypedConnector( Passive, Output );
550 TypedConnector( Active, Input );
551 TypedConnector( Active, Output );
553 # undef TypedConnector
554 # undef TypedConnector_Input
555 # undef TypedConnector_Output
559 /** \brief Connector actively reading packets
561 \tparam PacketType Type of packet to read. Defaults to senf::Packet
563 The %ActiveInput %connector template reads data actively from a connected %module. This
564 class is completely implemented via it's base-class, GenericActiveInput, the only
565 difference is that read packets are returned as \a PacketType instead of generic
566 senf::Packet references.
568 \see GenericActiveInput \n
571 template <class PacketType=Packet>
572 class ActiveInput : public GenericActiveInput
575 PacketType operator()(); ///< Read packet
576 /**< \throws std::bad_cast if the %connector receives a
577 Packet which is not of type \a PacketType.
578 \returns newly read packet reference. */
579 PacketType read(); ///< Alias for operator()
582 /** \brief Connector passively receiving packets
584 \tparam PacketType Type of packet to read. Defaults to senf::Packet
586 The %PassiveInput %connector template receives packets sent to it from a connected
587 %module. This class is completely implemented via it's base-class, GenericPassiveInput,
588 the only difference is that read packets are returned as \a PacketType instead of generic
589 senf::Packet references.
591 \see GenericPassiveInput \n
594 template <class PacketType=Packet>
595 class PassiveInput : public GenericPassiveInput
598 PacketType operator()(); ///< Read packet
599 /**< \throws std::bad_cast if the %connector receives a
600 Packet which is not of type \a PacketType.
601 \returns newly read packet reference. */
602 PacketType read(); ///< Alias for operator()
605 /** \brief Connector actively sending packets
607 \tparam PacketType Type of packet to send. Defaults to senf::Packet
609 The %ActiveOutput %connector template sends data actively to a connected %module. This
610 class is completely implemented via it's base-class, GenericActiveOutput, the only
611 difference is that it only sends packets of type \a PacketType.
613 \see GenericActiveOutput \n
616 template <class PacketType=Packet>
617 class ActiveOutput : public GenericActiveOutput
620 operator()(PacketType packet); ///< Send out a packet
621 void write(PacketType packet); ///< Alias for operator()
624 /** \brief Connector passively providing packets
626 \tparam PacketType Type of packet to send. Defaults to senf::Packet
628 The %PassiveOutput %connector template provides data passively to a connected %module
629 whenever signaled. This class is completely implemented via it's base-class,
630 GenericPassiveOutput, the only difference is that it only sends packets of type
633 \see GenericPassiveOutput \n
636 template <class PacketType=Packet>
637 class PassiveOutput : public GenericPassiveOutput
640 operator()(PacketType packet); ///< Send out a packet
641 void write(PacketType packet); ///< Alias for operator()
648 ///////////////////////////////hh.e////////////////////////////////////////
649 #include "Connectors.cci"
650 //#include "Connectors.ct"
651 #include "Connectors.cti"
658 // c-file-style: "senf"
659 // indent-tabs-mode: nil
660 // ispell-local-dictionary: "american"
661 // compile-command: "scons -u test"
662 // comment-column: 40