Emeric Vigier | 2f62582 | 2012-08-06 11:09:52 -0400 | [diff] [blame] | 1 | // Copyright (C) 2001,2002,2003,2004 Federico Montesino Pouzols <fedemp@altern.org>. |
| 2 | // |
| 3 | // This program is free software; you can redistribute it and/or modify |
| 4 | // it under the terms of the GNU General Public License as published by |
| 5 | // the Free Software Foundation; either version 2 of the License, or |
| 6 | // (at your option) any later version. |
| 7 | // |
| 8 | // This program is distributed in the hope that it will be useful, |
| 9 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | // GNU General Public License for more details. |
| 12 | // |
| 13 | // You should have received a copy of the GNU General Public License |
| 14 | // along with this program; if not, write to the Free Software |
| 15 | // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 16 | // |
| 17 | // As a special exception, you may use this file as part of a free software |
| 18 | // library without restriction. Specifically, if other files instantiate |
| 19 | // templates or use macros or inline functions from this file, or you compile |
| 20 | // this file and link it with other files to produce an executable, this |
| 21 | // file does not by itself cause the resulting executable to be covered by |
| 22 | // the GNU General Public License. This exception does not however |
| 23 | // invalidate any other reasons why the executable file might be covered by |
| 24 | // the GNU General Public License. |
| 25 | // |
| 26 | // This exception applies only to the code released under the name GNU |
| 27 | // ccRTP. If you copy code from other releases into a copy of GNU |
| 28 | // ccRTP, as the General Public License permits, the exception does |
| 29 | // not apply to the code that you add in this way. To avoid misleading |
| 30 | // anyone as to the status of such modified files, you must delete |
| 31 | // this exception notice from them. |
| 32 | // |
| 33 | // If you write modifications of your own for GNU ccRTP, it is your choice |
| 34 | // whether to permit this exception to apply to your modifications. |
| 35 | // If you do not wish that, delete this exception notice. |
| 36 | // |
| 37 | |
| 38 | /** |
| 39 | * @file sources.h |
| 40 | * |
| 41 | * @short Sources of synchronization and participants related clases. |
| 42 | **/ |
| 43 | |
| 44 | #ifndef CCXX_RTP_SOURCES_H_ |
| 45 | #define CCXX_RTP_SOURCES_H_ |
| 46 | |
| 47 | #include <string> |
| 48 | #include <ccrtp/rtcppkt.h> |
| 49 | |
| 50 | #ifdef CCXX_NAMESPACES |
| 51 | namespace ost { |
| 52 | #endif |
| 53 | |
| 54 | /** |
| 55 | * @defgroup sources Participants and synchronization sources. |
| 56 | * @{ |
| 57 | **/ |
| 58 | |
| 59 | /** |
| 60 | * @class SDESItemsHolder |
| 61 | * |
| 62 | * Holds the SDES items and related information from a participant in |
| 63 | * an RTP application. This is a base class for participant classes. |
| 64 | * |
| 65 | * @author Federico Montesino Pouzols <fedemp@altern.org> |
| 66 | **/ |
| 67 | class __EXPORT SDESItemsHolder |
| 68 | { |
| 69 | public: |
| 70 | const std::string& |
| 71 | getItem(SDESItemType type) const; |
| 72 | |
| 73 | inline const std::string& |
| 74 | getPRIVPrefix() const |
| 75 | { return sdesItems[SDESItemTypeEND]; } |
| 76 | |
| 77 | void |
| 78 | setItem(SDESItemType item, const std::string& val); |
| 79 | |
| 80 | inline void |
| 81 | setPRIVPrefix(const std::string& val) |
| 82 | { sdesItems[SDESItemTypeEND] = val; } |
| 83 | |
| 84 | protected: |
| 85 | SDESItemsHolder() |
| 86 | { } |
| 87 | |
| 88 | inline virtual ~SDESItemsHolder() |
| 89 | { } |
| 90 | |
| 91 | private: |
| 92 | // SDES items for a participant. |
| 93 | // sdesItems[0] (== sdesItems[SDESItemTypeEND]) holds the prefix |
| 94 | // value for the PRIV item. The rest of entries hold the |
| 95 | // correponding SDES item value. |
| 96 | std::string sdesItems[SDESItemTypeLast + 1]; |
| 97 | }; |
| 98 | |
| 99 | /** |
| 100 | * @class Participant |
| 101 | * @short A class of objects representing remote participants (RTP |
| 102 | * applications) in a multimedia session. |
| 103 | * |
| 104 | * Any RTP socket/queue class that directly or indirectly inherits |
| 105 | * from QueueRTCPManager (and hence has RTCP support) will represent |
| 106 | * participants from which any RTP or RTCP packet has been received |
| 107 | * through a Participant object. These Participant objects are |
| 108 | * entities such as end systems (user applications, monitors, etc), |
| 109 | * RTP mixers and RTP translators. |
| 110 | * |
| 111 | * Participant objects are identified by a CNAME and provide access to |
| 112 | * all known data about the source of RTP/RTCP packets, such as the |
| 113 | * CNAME and any other SDES item. Each participant object is related |
| 114 | * to one or more synchronization objects (@see SyncSource). |
| 115 | * |
| 116 | * If an RTP application based on ccRTP receives packets from itself |
| 117 | * (for instance, it is included in the destination list), there will |
| 118 | * be a Participant object that corresponds to the "local participant" |
| 119 | * (RTPApplication) object. |
| 120 | * |
| 121 | * @author Federico Montesino Pouzols <fedemp@altern.org> |
| 122 | * |
| 123 | * @todo implement reference counting from sources, so that when a |
| 124 | * source is destroyed, we know if the Participant should be |
| 125 | * destroyed. |
| 126 | **/ |
| 127 | class __EXPORT Participant : private SDESItemsHolder |
| 128 | { |
| 129 | public: |
| 130 | /** |
| 131 | * Get the value of an SDES item. For instance, |
| 132 | * getSDESItem(SDESItemTypeCNAME), return the CNAME of this |
| 133 | * Participant. |
| 134 | * |
| 135 | * @param type type of SDES item to get value of. |
| 136 | * |
| 137 | * @return value of the SDES item as a string. |
| 138 | * @retval empty string when the value is not known (no RTCP |
| 139 | * packet with the requested SDES item has been received from this |
| 140 | * source). |
| 141 | **/ |
| 142 | const std::string& |
| 143 | getSDESItem(SDESItemType type) const |
| 144 | { return SDESItemsHolder::getItem(type); } |
| 145 | |
| 146 | /** |
| 147 | * Get the prefix value for the PRIV SDES item. |
| 148 | * |
| 149 | * @return PRIV SDES item prefix as a string. |
| 150 | * @retval empty string when no PRIV SDES item has been |
| 151 | * received from this source. |
| 152 | **/ |
| 153 | inline const std::string& |
| 154 | getPRIVPrefix() const |
| 155 | { return SDESItemsHolder::getPRIVPrefix(); } |
| 156 | |
| 157 | /** |
| 158 | * Construct a new participant. |
| 159 | * |
| 160 | * @param cname Unique CNAME identifier. |
| 161 | **/ |
| 162 | Participant(const std::string& cname); |
| 163 | |
| 164 | ~Participant(); |
| 165 | |
| 166 | private: |
| 167 | friend class ParticipantHandler; |
| 168 | |
| 169 | /** |
| 170 | * Set the value of a SDES item. |
| 171 | **/ |
| 172 | inline void |
| 173 | setSDESItem(SDESItemType item, const std::string& val) |
| 174 | { SDESItemsHolder::setItem(item,val); } |
| 175 | |
| 176 | /** |
| 177 | * Set prefix value for the PRIV SDES item. |
| 178 | **/ |
| 179 | inline void |
| 180 | setPRIVPrefix(const std::string val) |
| 181 | { SDESItemsHolder::setPRIVPrefix(val); } |
| 182 | }; |
| 183 | |
| 184 | /** |
| 185 | * @class SyncSource |
| 186 | * @short Synchronization source in an RTP session |
| 187 | * |
| 188 | * Each synchronization source in an RTP session is identified by a |
| 189 | * 32-bit numeric SSRC identifier. Each SyncSource object is related |
| 190 | * to a Participant object, which can be retrieved through the |
| 191 | * getParticipant() method. |
| 192 | * |
| 193 | * @author Federico Montesino Pouzols <fedemp@altern.org> |
| 194 | **/ |
| 195 | class __EXPORT SyncSource |
| 196 | { |
| 197 | public: |
| 198 | /** |
| 199 | * @enum State |
| 200 | * |
| 201 | * @short Synchronization source states during an RTP session. |
| 202 | * |
| 203 | * In general, new synchronization sources are not considered |
| 204 | * valid until multiple valid data packets or a valid RTCP |
| 205 | * compound packet has been received from the new source (@see |
| 206 | * IncomingDataQueue::setMinValidPacketSequence()). Thus, the |
| 207 | * source will probably be in statePrevalid before reaching |
| 208 | * one of the two states that indicate a valid source: |
| 209 | * stateActive and stateInactive. |
| 210 | * |
| 211 | * A valid participant is in stateActive state if RTP and/or |
| 212 | * RTCP packets are currently being received from it. If, |
| 213 | * after a small number of RTCP report intervals (see |
| 214 | * IncomingDataQueue::setSourceExpirationPeriod() ), no |
| 215 | * packets are received, it will reach the stateInactive |
| 216 | * state. If, after a small number of RTCP report intervals, |
| 217 | * no packet is received from an inactive source, it will be |
| 218 | * deleted. |
| 219 | * |
| 220 | * If RTCP is being used, after receiving a BYE RTCP packet |
| 221 | * from a synchronization source, it will reach the |
| 222 | * stateLeaving state and will be deleted after a delay (see |
| 223 | * QueueRTCPManager::setLeavingDelay()). |
| 224 | * |
| 225 | * Sources in statePrevalid and stateLeaving are not counted |
| 226 | * for the number of session members estimation. |
| 227 | **/ |
| 228 | typedef enum { |
| 229 | stateUnknown, ///< No valid packet has been received. |
| 230 | statePrevalid, ///< Some packets have been |
| 231 | ///received, but source validity not |
| 232 | ///yet guaranteed. |
| 233 | stateActive, ///< We currently receive packets |
| 234 | ///(data or control) from this source. |
| 235 | stateInactive, ///< Was active in the near past but |
| 236 | ///no packet from this source has |
| 237 | ///been received lately. |
| 238 | stateLeaving ///< An RTCP BYE has been received |
| 239 | ///from the source. |
| 240 | } State; |
| 241 | |
| 242 | /** |
| 243 | * @param ssrc SSRC identifier of the source, unique in each |
| 244 | * session. |
| 245 | */ |
| 246 | SyncSource(uint32 ssrc); |
| 247 | |
| 248 | ~SyncSource(); |
| 249 | |
| 250 | State |
| 251 | getState() const |
| 252 | { return state; } |
| 253 | |
| 254 | /** |
| 255 | * Whether this source sends RTP data packets. |
| 256 | **/ |
| 257 | bool isSender() const |
| 258 | { return activeSender; } |
| 259 | |
| 260 | uint32 getID() const |
| 261 | { return SSRC; } |
| 262 | |
| 263 | /** |
| 264 | * Get the participant this synchronization source is |
| 265 | * asociated to. |
| 266 | * |
| 267 | * @retval NULL if the stack has not been yet able to identify |
| 268 | * the participant this source is associated to. |
| 269 | **/ |
| 270 | inline Participant* |
| 271 | getParticipant() const |
| 272 | { return participant; } |
| 273 | |
| 274 | tpport_t getDataTransportPort() const |
| 275 | { return dataTransportPort; } |
| 276 | |
| 277 | tpport_t getControlTransportPort() const |
| 278 | { return controlTransportPort; } |
| 279 | |
| 280 | const InetAddress& getNetworkAddress() const |
| 281 | { return networkAddress; } |
| 282 | |
| 283 | protected: |
| 284 | /** |
| 285 | * @param source The RTPSource object being copied |
| 286 | */ |
| 287 | SyncSource(const SyncSource& source); |
| 288 | |
| 289 | SyncSource& |
| 290 | operator=(const SyncSource& source); |
| 291 | |
| 292 | private: |
| 293 | friend class SyncSourceHandler; |
| 294 | |
| 295 | inline void |
| 296 | setState(State st) |
| 297 | { state = st; } |
| 298 | |
| 299 | /** |
| 300 | * Mark this source as an active sender. |
| 301 | **/ |
| 302 | inline void |
| 303 | setSender(bool active) |
| 304 | { activeSender = active; } |
| 305 | |
| 306 | inline void |
| 307 | setParticipant(Participant& p) |
| 308 | { participant = &p; } |
| 309 | |
| 310 | void setDataTransportPort(tpport_t p) |
| 311 | { dataTransportPort = p; } |
| 312 | |
| 313 | void setControlTransportPort(tpport_t p) |
| 314 | { controlTransportPort = p; } |
| 315 | |
| 316 | void setNetworkAddress(InetAddress addr) |
| 317 | { networkAddress = addr; } |
| 318 | |
| 319 | inline void |
| 320 | setLink(void *l) |
| 321 | { link = l; } |
| 322 | |
| 323 | void *getLink() const |
| 324 | { return link; } |
| 325 | |
| 326 | // validity state of this source |
| 327 | State state; |
| 328 | // 32-bit SSRC identifier. |
| 329 | uint32 SSRC; |
| 330 | // A valid source not always is active |
| 331 | bool activeSender; |
| 332 | // The corresponding participant. |
| 333 | Participant* participant; |
| 334 | |
| 335 | // Network protocol address for data and control connection |
| 336 | // (both are assumed to be the same). |
| 337 | InetAddress networkAddress; |
| 338 | tpport_t dataTransportPort; |
| 339 | tpport_t controlTransportPort; |
| 340 | |
| 341 | // Pointer to the SyncSourceLink or similar object in the |
| 342 | // service queue. Saves a lot of searches in the membership |
| 343 | // table. |
| 344 | void* link; |
| 345 | }; |
| 346 | |
| 347 | /** |
| 348 | * @class RTPApplication |
| 349 | * @short An RTP application, holding identifying RTCP SDES item |
| 350 | * values. Represents local participants. |
| 351 | * |
| 352 | * An application in the context of RTP: an entity that has a CNAME |
| 353 | * (unique identifier in the form of user\@host.domain) as well as |
| 354 | * other RTCP SDES items (such as NAME or TOOL), and may open a number |
| 355 | * of RTP sessions. Each application is a different source of |
| 356 | * synchronization (with a potentially diferent SSRC identifier) in |
| 357 | * each RTP session it participates. All the sources of |
| 358 | * synchronization from a participant are tied together by means of |
| 359 | * the CNAME. |
| 360 | * |
| 361 | * The definition of this class allows applications based on ccRTP to |
| 362 | * implement several "RTP applications" in the same process. Each |
| 363 | * object of this class represents a local participant. |
| 364 | * |
| 365 | * @author Federico Montesino Pouzols <fedemp@altern.org> |
| 366 | **/ |
| 367 | class __EXPORT RTPApplication : private SDESItemsHolder |
| 368 | { |
| 369 | private: |
| 370 | struct ParticipantLink; |
| 371 | |
| 372 | public: |
| 373 | /** |
| 374 | * Create a new RTP application. If the CNAME string provided |
| 375 | * has zero length, it is guessed from the user and machine |
| 376 | * name. |
| 377 | * |
| 378 | * @param cname Local participant canonical name. |
| 379 | **/ |
| 380 | RTPApplication(const std::string& cname); |
| 381 | |
| 382 | ~RTPApplication(); |
| 383 | |
| 384 | inline void |
| 385 | setSDESItem(SDESItemType item, const std::string& val) |
| 386 | { SDESItemsHolder::setItem(item,val); } |
| 387 | |
| 388 | inline void |
| 389 | setPRIVPrefix(const std::string& val) |
| 390 | { SDESItemsHolder::setPRIVPrefix(val); } |
| 391 | |
| 392 | const std::string& |
| 393 | getSDESItem(SDESItemType item) const |
| 394 | { return SDESItemsHolder::getItem(item); } |
| 395 | |
| 396 | inline const std::string& |
| 397 | getPRIVPrefix() const |
| 398 | { return SDESItemsHolder::getPRIVPrefix(); } |
| 399 | |
| 400 | /** |
| 401 | * Iterator through the list of participants in this |
| 402 | * session. Somehow resembles and standard const_iterator |
| 403 | **/ |
| 404 | class ParticipantsIterator |
| 405 | { |
| 406 | public: |
| 407 | typedef std::forward_iterator_tag iterator_category; |
| 408 | typedef Participant value_type; |
| 409 | typedef ptrdiff_t difference_type; |
| 410 | typedef const Participant* pointer; |
| 411 | typedef const Participant& reference; |
| 412 | |
| 413 | ParticipantsIterator(ParticipantLink* p = NULL) : |
| 414 | link(p) |
| 415 | { } |
| 416 | |
| 417 | ParticipantsIterator(const ParticipantsIterator& pi) : |
| 418 | link(pi.link) |
| 419 | { } |
| 420 | |
| 421 | reference operator*() const |
| 422 | { return *(link->getParticipant()); } |
| 423 | |
| 424 | pointer operator->() const |
| 425 | { return link->getParticipant(); } |
| 426 | |
| 427 | ParticipantsIterator& operator++() { |
| 428 | link = link->getNext(); |
| 429 | return *this; |
| 430 | } |
| 431 | |
| 432 | ParticipantsIterator operator++(int) { |
| 433 | ParticipantsIterator result(*this); |
| 434 | ++(*this); |
| 435 | return result; |
| 436 | } |
| 437 | friend bool operator==(const ParticipantsIterator& l, |
| 438 | const ParticipantsIterator& r) |
| 439 | { return l.link == r.link; } |
| 440 | |
| 441 | friend bool operator!=(const ParticipantsIterator& l, |
| 442 | const ParticipantsIterator& r) |
| 443 | { return l.link != r.link; } |
| 444 | private: |
| 445 | ParticipantLink *link; |
| 446 | }; |
| 447 | |
| 448 | ParticipantsIterator begin() |
| 449 | { return ParticipantsIterator(firstPart); } |
| 450 | |
| 451 | ParticipantsIterator end() |
| 452 | { return ParticipantsIterator(NULL); } |
| 453 | |
| 454 | const Participant* |
| 455 | getParticipant(const std::string& cname) const; |
| 456 | |
| 457 | private: |
| 458 | friend class ApplicationHandler; |
| 459 | |
| 460 | struct ParticipantLink { |
| 461 | ParticipantLink(Participant& p, |
| 462 | ParticipantLink* l) : |
| 463 | participant(&p), next(l) |
| 464 | { } |
| 465 | inline ~ParticipantLink() { delete participant; } |
| 466 | inline Participant* getParticipant() { return participant; } |
| 467 | inline ParticipantLink* getPrev() { return prev; } |
| 468 | inline ParticipantLink* getNext() { return next; } |
| 469 | inline void setPrev(ParticipantLink* l) { prev = l; } |
| 470 | inline void setNext(ParticipantLink* l) { next = l; } |
| 471 | Participant* participant; |
| 472 | ParticipantLink* next, *prev; |
| 473 | }; |
| 474 | |
| 475 | void |
| 476 | addParticipant(Participant& part); |
| 477 | |
| 478 | void |
| 479 | removeParticipant(ParticipantLink* part); |
| 480 | |
| 481 | /** |
| 482 | * Find out the local CNAME as user\@host and store it as part |
| 483 | * of the internal state of this class. |
| 484 | */ |
| 485 | void |
| 486 | findCNAME(); |
| 487 | |
| 488 | /// Hash table with sources of RTP and RTCP packets. |
| 489 | static const size_t defaultParticipantsNum; |
| 490 | Participant** participants; |
| 491 | /// List of participants, ordered from older to newer. |
| 492 | ParticipantLink* firstPart, * lastPart; |
| 493 | }; |
| 494 | |
| 495 | /** |
| 496 | * Get the RTPApplication object for the "default" application (the |
| 497 | * only one used by common applications -those that only implement one |
| 498 | * "RTP application"). Note that this application object differs from |
| 499 | * all the others that may be defined in that it is automatically |
| 500 | * constructed by the ccRTP stack and its CNAME is automatically |
| 501 | * assigned (as user\@host), whereas the other application objects' |
| 502 | * CNAME is provided to its constructor. |
| 503 | **/ |
| 504 | __EXPORT RTPApplication& defaultApplication(); |
| 505 | |
| 506 | /** @}*/ // sources |
| 507 | |
| 508 | #ifdef CCXX_NAMESPACES |
| 509 | } |
| 510 | #endif |
| 511 | |
| 512 | #endif //CCXX_RTP_SOURCES_H_ |
| 513 | |
| 514 | /** EMACS ** |
| 515 | * Local variables: |
| 516 | * mode: c++ |
| 517 | * c-basic-offset: 8 |
| 518 | * End: |
| 519 | */ |