dburgess | 82c46ff | 2011-10-07 02:40:51 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2008, 2011 Free Software Foundation, Inc. |
| 3 | * |
| 4 | * This software is distributed under the terms of the GNU Affero Public License. |
| 5 | * See the COPYING file in the main directory for details. |
| 6 | * |
| 7 | * This use of this software may be subject to additional restrictions. |
| 8 | * See the LEGAL file in the main directory for details. |
| 9 | |
| 10 | This program is free software: you can redistribute it and/or modify |
| 11 | it under the terms of the GNU Affero General Public License as published by |
| 12 | the Free Software Foundation, either version 3 of the License, or |
| 13 | (at your option) any later version. |
| 14 | |
| 15 | This program is distributed in the hope that it will be useful, |
| 16 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | GNU Affero General Public License for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU Affero General Public License |
| 21 | along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 22 | |
| 23 | */ |
| 24 | |
| 25 | |
| 26 | #ifndef INTERTHREAD_H |
| 27 | #define INTERTHREAD_H |
| 28 | |
| 29 | #include "Timeval.h" |
| 30 | #include "Threads.h" |
| 31 | #include "LinkedLists.h" |
| 32 | #include <map> |
| 33 | #include <vector> |
| 34 | #include <queue> |
| 35 | |
| 36 | |
| 37 | |
| 38 | |
| 39 | |
| 40 | /**@defgroup Templates for interthread mechanisms. */ |
| 41 | //@{ |
| 42 | |
| 43 | |
| 44 | /** Pointer FIFO for interthread operations. */ |
| 45 | template <class T> class InterthreadQueue { |
| 46 | |
| 47 | protected: |
| 48 | |
| 49 | PointerFIFO mQ; |
| 50 | mutable Mutex mLock; |
| 51 | mutable Signal mWriteSignal; |
| 52 | |
| 53 | |
| 54 | public: |
| 55 | |
| 56 | /** Delete contents. */ |
| 57 | void clear() |
| 58 | { |
| 59 | ScopedLock lock(mLock); |
| 60 | while (mQ.size()>0) delete (T*)mQ.get(); |
| 61 | } |
| 62 | |
| 63 | /** Empty the queue, but don't delete. */ |
| 64 | void flushNoDelete() |
| 65 | { |
| 66 | ScopedLock lock(mLock); |
| 67 | while (mQ.size()>0) mQ.get(); |
| 68 | } |
| 69 | |
| 70 | |
| 71 | ~InterthreadQueue() |
| 72 | { clear(); } |
| 73 | |
| 74 | |
| 75 | size_t size() const |
| 76 | { |
| 77 | ScopedLock lock(mLock); |
| 78 | return mQ.size(); |
| 79 | } |
| 80 | |
| 81 | /** |
| 82 | Blocking read. |
| 83 | @return Pointer to object (will not be NULL). |
| 84 | */ |
| 85 | T* read() |
| 86 | { |
| 87 | ScopedLock lock(mLock); |
| 88 | T* retVal = (T*)mQ.get(); |
| 89 | while (retVal==NULL) { |
| 90 | mWriteSignal.wait(mLock); |
| 91 | retVal = (T*)mQ.get(); |
| 92 | } |
| 93 | return retVal; |
| 94 | } |
| 95 | |
| 96 | /** |
| 97 | Blocking read with a timeout. |
| 98 | @param timeout The read timeout in ms. |
| 99 | @return Pointer to object or NULL on timeout. |
| 100 | */ |
| 101 | T* read(unsigned timeout) |
| 102 | { |
| 103 | if (timeout==0) return readNoBlock(); |
| 104 | Timeval waitTime(timeout); |
| 105 | ScopedLock lock(mLock); |
| 106 | while ((mQ.size()==0) && (!waitTime.passed())) |
| 107 | mWriteSignal.wait(mLock,waitTime.remaining()); |
| 108 | T* retVal = (T*)mQ.get(); |
| 109 | return retVal; |
| 110 | } |
| 111 | |
| 112 | /** |
| 113 | Non-blocking read. |
| 114 | @return Pointer to object or NULL if FIFO is empty. |
| 115 | */ |
| 116 | T* readNoBlock() |
| 117 | { |
| 118 | ScopedLock lock(mLock); |
| 119 | return (T*)mQ.get(); |
| 120 | } |
| 121 | |
| 122 | /** Non-blocking write. */ |
| 123 | void write(T* val) |
| 124 | { |
| 125 | ScopedLock lock(mLock); |
| 126 | mQ.put(val); |
| 127 | mWriteSignal.signal(); |
| 128 | } |
| 129 | |
| 130 | |
| 131 | }; |
| 132 | |
| 133 | |
| 134 | |
| 135 | /** Pointer FIFO for interthread operations. */ |
| 136 | template <class T> class InterthreadQueueWithWait { |
| 137 | |
| 138 | protected: |
| 139 | |
| 140 | PointerFIFO mQ; |
| 141 | mutable Mutex mLock; |
| 142 | mutable Signal mWriteSignal; |
| 143 | mutable Signal mReadSignal; |
| 144 | |
| 145 | virtual void freeElement(T* element) const { delete element; }; |
| 146 | |
| 147 | public: |
| 148 | |
| 149 | /** Delete contents. */ |
| 150 | void clear() |
| 151 | { |
| 152 | ScopedLock lock(mLock); |
| 153 | while (mQ.size()>0) freeElement((T*)mQ.get()); |
| 154 | mReadSignal.signal(); |
| 155 | } |
| 156 | |
| 157 | |
| 158 | |
| 159 | virtual ~InterthreadQueueWithWait() |
| 160 | { clear(); } |
| 161 | |
| 162 | |
| 163 | size_t size() const |
| 164 | { |
| 165 | ScopedLock lock(mLock); |
| 166 | return mQ.size(); |
| 167 | } |
| 168 | |
| 169 | /** |
| 170 | Blocking read. |
| 171 | @return Pointer to object (will not be NULL). |
| 172 | */ |
| 173 | T* read() |
| 174 | { |
| 175 | ScopedLock lock(mLock); |
| 176 | T* retVal = (T*)mQ.get(); |
| 177 | while (retVal==NULL) { |
| 178 | mWriteSignal.wait(mLock); |
| 179 | retVal = (T*)mQ.get(); |
| 180 | } |
| 181 | mReadSignal.signal(); |
| 182 | return retVal; |
| 183 | } |
| 184 | |
| 185 | /** |
| 186 | Blocking read with a timeout. |
| 187 | @param timeout The read timeout in ms. |
| 188 | @return Pointer to object or NULL on timeout. |
| 189 | */ |
| 190 | T* read(unsigned timeout) |
| 191 | { |
| 192 | if (timeout==0) return readNoBlock(); |
| 193 | Timeval waitTime(timeout); |
| 194 | ScopedLock lock(mLock); |
| 195 | while ((mQ.size()==0) && (!waitTime.passed())) |
| 196 | mWriteSignal.wait(mLock,waitTime.remaining()); |
| 197 | T* retVal = (T*)mQ.get(); |
| 198 | if (retVal!=NULL) mReadSignal.signal(); |
| 199 | return retVal; |
| 200 | } |
| 201 | |
| 202 | /** |
| 203 | Non-blocking read. |
| 204 | @return Pointer to object or NULL if FIFO is empty. |
| 205 | */ |
| 206 | T* readNoBlock() |
| 207 | { |
| 208 | ScopedLock lock(mLock); |
| 209 | T* retVal = (T*)mQ.get(); |
| 210 | if (retVal!=NULL) mReadSignal.signal(); |
| 211 | return retVal; |
| 212 | } |
| 213 | |
| 214 | /** Non-blocking write. */ |
| 215 | void write(T* val) |
| 216 | { |
| 217 | ScopedLock lock(mLock); |
| 218 | mQ.put(val); |
| 219 | mWriteSignal.signal(); |
| 220 | } |
| 221 | |
| 222 | /** Wait until the queue falls below a low water mark. */ |
| 223 | void wait(size_t sz=0) |
| 224 | { |
| 225 | ScopedLock lock(mLock); |
| 226 | while (mQ.size()>sz) mReadSignal.wait(mLock); |
| 227 | } |
| 228 | |
| 229 | }; |
| 230 | |
| 231 | |
| 232 | |
| 233 | |
| 234 | |
| 235 | /** Thread-safe map of pointers to class D, keyed by class K. */ |
| 236 | template <class K, class D > class InterthreadMap { |
| 237 | |
| 238 | protected: |
| 239 | |
| 240 | typedef std::map<K,D*> Map; |
| 241 | Map mMap; |
| 242 | mutable Mutex mLock; |
| 243 | Signal mWriteSignal; |
| 244 | |
| 245 | public: |
| 246 | |
| 247 | void clear() |
| 248 | { |
| 249 | // Delete everything in the map. |
| 250 | ScopedLock lock(mLock); |
| 251 | typename Map::iterator iter = mMap.begin(); |
| 252 | while (iter != mMap.end()) { |
| 253 | delete iter->second; |
| 254 | ++iter; |
| 255 | } |
| 256 | mMap.clear(); |
| 257 | } |
| 258 | |
| 259 | ~InterthreadMap() { clear(); } |
| 260 | |
| 261 | /** |
| 262 | Non-blocking write. |
| 263 | @param key The index to write to. |
| 264 | @param wData Pointer to data, not to be deleted until removed from the map. |
| 265 | */ |
| 266 | void write(const K &key, D * wData) |
| 267 | { |
| 268 | ScopedLock lock(mLock); |
| 269 | typename Map::iterator iter = mMap.find(key); |
| 270 | if (iter!=mMap.end()) { |
| 271 | delete iter->second; |
| 272 | iter->second = wData; |
| 273 | } else { |
| 274 | mMap[key] = wData; |
| 275 | } |
| 276 | mWriteSignal.broadcast(); |
| 277 | } |
| 278 | |
| 279 | /** |
| 280 | Non-blocking read with element removal. |
| 281 | @param key Key to read from. |
| 282 | @return Pointer at key or NULL if key not found, to be deleted by caller. |
| 283 | */ |
| 284 | D* getNoBlock(const K& key) |
| 285 | { |
| 286 | ScopedLock lock(mLock); |
| 287 | typename Map::iterator iter = mMap.find(key); |
| 288 | if (iter==mMap.end()) return NULL; |
| 289 | D* retVal = iter->second; |
| 290 | mMap.erase(iter); |
| 291 | return retVal; |
| 292 | } |
| 293 | |
| 294 | /** |
| 295 | Blocking read with a timeout and element removal. |
| 296 | @param key The key to read from. |
| 297 | @param timeout The blocking timeout in ms. |
| 298 | @return Pointer at key or NULL on timeout, to be deleted by caller. |
| 299 | */ |
| 300 | D* get(const K &key, unsigned timeout) |
| 301 | { |
| 302 | if (timeout==0) return getNoBlock(key); |
| 303 | Timeval waitTime(timeout); |
| 304 | ScopedLock lock(mLock); |
| 305 | typename Map::iterator iter = mMap.find(key); |
| 306 | while ((iter==mMap.end()) && (!waitTime.passed())) { |
| 307 | mWriteSignal.wait(mLock,waitTime.remaining()); |
| 308 | iter = mMap.find(key); |
| 309 | } |
| 310 | if (iter==mMap.end()) return NULL; |
| 311 | D* retVal = iter->second; |
| 312 | mMap.erase(iter); |
| 313 | return retVal; |
| 314 | } |
| 315 | |
| 316 | /** |
| 317 | Blocking read with and element removal. |
| 318 | @param key The key to read from. |
| 319 | @return Pointer at key, to be deleted by caller. |
| 320 | */ |
| 321 | D* get(const K &key) |
| 322 | { |
| 323 | ScopedLock lock(mLock); |
| 324 | typename Map::iterator iter = mMap.find(key); |
| 325 | while (iter==mMap.end()) { |
| 326 | mWriteSignal.wait(mLock); |
| 327 | iter = mMap.find(key); |
| 328 | } |
| 329 | D* retVal = iter->second; |
| 330 | mMap.erase(iter); |
| 331 | return retVal; |
| 332 | } |
| 333 | |
| 334 | |
| 335 | /** |
| 336 | Remove an entry and delete it. |
| 337 | @param key The key of the entry to delete. |
| 338 | @return True if it was actually found and deleted. |
| 339 | */ |
| 340 | bool remove(const K &key ) |
| 341 | { |
| 342 | D* val = getNoBlock(key); |
| 343 | if (!val) return false; |
| 344 | delete val; |
| 345 | return true; |
| 346 | } |
| 347 | |
| 348 | |
| 349 | /** |
| 350 | Non-blocking read. |
| 351 | @param key Key to read from. |
| 352 | @return Pointer at key or NULL if key not found. |
| 353 | */ |
| 354 | D* readNoBlock(const K& key) const |
| 355 | { |
| 356 | D* retVal=NULL; |
| 357 | ScopedLock lock(mLock); |
| 358 | typename Map::const_iterator iter = mMap.find(key); |
| 359 | if (iter!=mMap.end()) retVal = iter->second; |
| 360 | return retVal; |
| 361 | } |
| 362 | |
| 363 | /** |
| 364 | Blocking read with a timeout. |
| 365 | @param key The key to read from. |
| 366 | @param timeout The blocking timeout in ms. |
| 367 | @return Pointer at key or NULL on timeout. |
| 368 | */ |
| 369 | D* read(const K &key, unsigned timeout) const |
| 370 | { |
| 371 | if (timeout==0) return readNoBlock(key); |
| 372 | ScopedLock lock(mLock); |
| 373 | Timeval waitTime(timeout); |
| 374 | typename Map::const_iterator iter = mMap.find(key); |
| 375 | while ((iter==mMap.end()) && (!waitTime.passed())) { |
| 376 | mWriteSignal.wait(mLock,waitTime.remaining()); |
| 377 | iter = mMap.find(key); |
| 378 | } |
| 379 | if (iter==mMap.end()) return NULL; |
| 380 | D* retVal = iter->second; |
| 381 | return retVal; |
| 382 | } |
| 383 | |
| 384 | /** |
| 385 | Blocking read. |
| 386 | @param key The key to read from. |
| 387 | @return Pointer at key. |
| 388 | */ |
| 389 | D* read(const K &key) const |
| 390 | { |
| 391 | ScopedLock lock(mLock); |
| 392 | typename Map::const_iterator iter = mMap.find(key); |
| 393 | while (iter==mMap.end()) { |
| 394 | mWriteSignal.wait(mLock); |
| 395 | iter = mMap.find(key); |
| 396 | } |
| 397 | D* retVal = iter->second; |
| 398 | return retVal; |
| 399 | } |
| 400 | |
| 401 | }; |
| 402 | |
| 403 | |
| 404 | |
| 405 | |
| 406 | |
| 407 | |
| 408 | |
| 409 | /** This class is used to provide pointer-based comparison in priority_queues. */ |
| 410 | template <class T> class PointerCompare { |
| 411 | |
| 412 | public: |
| 413 | |
| 414 | /** Compare the objects pointed to, not the pointers themselves. */ |
| 415 | bool operator()(const T *v1, const T *v2) |
| 416 | { return (*v1)>(*v2); } |
| 417 | |
| 418 | }; |
| 419 | |
| 420 | |
| 421 | |
| 422 | /** |
| 423 | Priority queue for interthread operations. |
| 424 | Passes pointers to objects. |
| 425 | */ |
| 426 | template <class T, class C = std::vector<T*>, class Cmp = PointerCompare<T> > class InterthreadPriorityQueue { |
| 427 | |
| 428 | protected: |
| 429 | |
| 430 | std::priority_queue<T*,C,Cmp> mQ; |
| 431 | mutable Mutex mLock; |
| 432 | mutable Signal mWriteSignal; |
| 433 | |
| 434 | public: |
| 435 | |
| 436 | |
| 437 | /** Clear the FIFO. */ |
| 438 | void clear() |
| 439 | { |
| 440 | ScopedLock lock(mLock); |
| 441 | while (mQ.size()>0) { |
| 442 | T* ptr = mQ.top(); |
| 443 | mQ.pop(); |
| 444 | delete ptr; |
| 445 | } |
| 446 | } |
| 447 | |
| 448 | |
| 449 | ~InterthreadPriorityQueue() |
| 450 | { |
| 451 | clear(); |
| 452 | } |
| 453 | |
| 454 | size_t size() const |
| 455 | { |
| 456 | ScopedLock lock(mLock); |
| 457 | return mQ.size(); |
| 458 | } |
| 459 | |
| 460 | |
| 461 | /** Non-blocking read. */ |
| 462 | T* readNoBlock() |
| 463 | { |
| 464 | ScopedLock lock(mLock); |
| 465 | T* retVal = NULL; |
| 466 | if (mQ.size()!=0) { |
| 467 | retVal = mQ.top(); |
| 468 | mQ.pop(); |
| 469 | } |
| 470 | return retVal; |
| 471 | } |
| 472 | |
| 473 | /** Blocking read. */ |
| 474 | T* read() |
| 475 | { |
| 476 | ScopedLock lock(mLock); |
| 477 | T* retVal; |
| 478 | while (mQ.size()==0) mWriteSignal.wait(mLock); |
| 479 | retVal = mQ.top(); |
| 480 | mQ.pop(); |
| 481 | return retVal; |
| 482 | } |
| 483 | |
| 484 | /** Non-blocking write. */ |
| 485 | void write(T* val) |
| 486 | { |
| 487 | ScopedLock lock(mLock); |
| 488 | mQ.push(val); |
| 489 | mWriteSignal.signal(); |
| 490 | } |
| 491 | |
| 492 | }; |
| 493 | |
| 494 | |
| 495 | |
| 496 | |
| 497 | |
| 498 | class Semaphore { |
| 499 | |
| 500 | private: |
| 501 | |
| 502 | bool mFlag; |
| 503 | Signal mSignal; |
| 504 | mutable Mutex mLock; |
| 505 | |
| 506 | public: |
| 507 | |
| 508 | Semaphore() |
| 509 | :mFlag(false) |
| 510 | { } |
| 511 | |
| 512 | void post() |
| 513 | { |
| 514 | ScopedLock lock(mLock); |
| 515 | mFlag=true; |
| 516 | mSignal.signal(); |
| 517 | } |
| 518 | |
| 519 | void get() |
| 520 | { |
| 521 | ScopedLock lock(mLock); |
| 522 | while (!mFlag) mSignal.wait(mLock); |
| 523 | mFlag=false; |
| 524 | } |
| 525 | |
| 526 | bool semtry() |
| 527 | { |
| 528 | ScopedLock lock(mLock); |
| 529 | bool retVal = mFlag; |
| 530 | mFlag = false; |
| 531 | return retVal; |
| 532 | } |
| 533 | |
| 534 | }; |
| 535 | |
| 536 | |
| 537 | |
| 538 | |
| 539 | |
| 540 | //@} |
| 541 | |
| 542 | |
| 543 | |
| 544 | |
| 545 | #endif |
| 546 | // vim: ts=4 sw=4 |