granicus.if.org Git - imagemagick/blob - MagickCore/semaphore.c

   1 /*
   2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   3 %                                                                             %
   4 %                                                                             %
   5 %                                                                             %
   6 %        SSSSS  EEEEE  M   M   AAA   PPPP   H   H   OOO   RRRR   EEEEE        %
   7 %        SS     E      MM MM  A   A  P   P  H   H  O   O  R   R  E            %
   8 %         SSS   EEE    M M M  AAAAA  PPPP   HHHHH  O   O  RRRR   EEE          %
   9 %           SS  E      M   M  A   A  P      H   H  O   O  R R    E            %
  10 %        SSSSS  EEEEE  M   M  A   A  P      H   H   OOO   R  R   EEEEE        %
  11 %                                                                             %
  12 %                                                                             %
  13 %                        MagickCore Semaphore Methods                         %
  14 %                                                                             %
  15 %                              Software Design                                %
  16 %                             William Radcliffe                               %
  17 %                                John Cristy                                  %
  18 %                                 June 2000                                   %
  19 %                                                                             %
  20 %                                                                             %
  21 %  Copyright 1999-2012 ImageMagick Studio LLC, a non-profit organization      %
  22 %  dedicated to making software imaging solutions freely available.           %
  23 %                                                                             %
  24 %  You may not use this file except in compliance with the License.  You may  %
  25 %  obtain a copy of the License at                                            %
  26 %                                                                             %
  27 %    http://www.imagemagick.org/script/license.php                            %
  28 %                                                                             %
  29 %  Unless required by applicable law or agreed to in writing, software        %
  30 %  distributed under the License is distributed on an "AS IS" BASIS,          %
  31 %  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   %
  32 %  See the License for the specific language governing permissions and        %
  33 %  limitations under the License.                                             %
  34 %                                                                             %
  35 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  36 %
  37 %
  38 %
  39 */
  40 \f
  41 /*
  42   Include declarations.
  43 */
  44 #include "MagickCore/studio.h"
  45 #include "MagickCore/exception.h"
  46 #include "MagickCore/exception-private.h"
  47 #include "MagickCore/memory_.h"
  48 #include "MagickCore/memory-private.h"
  49 #include "MagickCore/semaphore.h"
  50 #include "MagickCore/semaphore-private.h"
  51 #include "MagickCore/string_.h"
  52 #include "MagickCore/thread_.h"
  53 #include "MagickCore/thread-private.h"
  54 \f
  55 /*
  56   Struct declaractions.
  57 */
  58 struct SemaphoreInfo
  59 {
  60   MagickMutexType
  61     mutex;
  62
  63   MagickThreadType
  64     id;
  65
  66   ssize_t
  67     reference_count;
  68
  69   size_t
  70     signature;
  71 };
  72 \f
  73 /*
  74 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  75 %                                                                             %
  76 %                                                                             %
  77 %                                                                             %
  78 %   A c q u i r e S e m a p h o r e I n f o                                   %
  79 %                                                                             %
  80 %                                                                             %
  81 %                                                                             %
  82 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  83 %
  84 %  AcquireSemaphoreInfo() acquires a semaphore.
  85 %
  86 %  The format of the AcquireSemaphoreInfo method is:
  87 %
  88 %      void AcquireSemaphoreInfo(SemaphoreInfo **semaphore_info)
  89 %
  90 %  A description of each parameter follows:
  91 %
  92 %    o semaphore_info: Specifies a pointer to an SemaphoreInfo structure.
  93 %
  94 */
  95 MagickExport void AcquireSemaphoreInfo(SemaphoreInfo **semaphore_info)
  96 {
  97   assert(semaphore_info != (SemaphoreInfo **) NULL);
  98   if (*semaphore_info == (SemaphoreInfo *) NULL)
  99     {
 100       LockMagickMutex();
 101       if (*semaphore_info == (SemaphoreInfo *) NULL)
 102         *semaphore_info=AllocateSemaphoreInfo();
 103       UnlockMagickMutex();
 104     }
 105 }
 106 \f
 107 /*
 108 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 109 %                                                                             %
 110 %                                                                             %
 111 %                                                                             %
 112 %   A l l o c a t e S e m a p h o r e I n f o                                 %
 113 %                                                                             %
 114 %                                                                             %
 115 %                                                                             %
 116 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 117 %
 118 %  AllocateSemaphoreInfo() initializes the SemaphoreInfo structure.
 119 %
 120 %  The format of the AllocateSemaphoreInfo method is:
 121 %
 122 %      SemaphoreInfo *AllocateSemaphoreInfo(void)
 123 %
 124 */
 125
 126 static void *AcquireSemaphoreMemory(const size_t size)
 127 {
 128 #if defined(MAGICKCORE_HAVE_POSIX_MEMALIGN)
 129   {
 130     void
 131       *memory;
 132
 133     if (posix_memalign(&memory,CACHE_LINE_SIZE,CacheAlign(size)) == 0)
 134       return(memory);
 135   }
 136 #endif
 137   return(malloc(CacheAlign(size)));
 138 }
 139
 140 MagickExport SemaphoreInfo *AllocateSemaphoreInfo(void)
 141 {
 142   SemaphoreInfo
 143     *semaphore_info;
 144
 145   /*
 146     Allocate semaphore.
 147   */
 148   semaphore_info=(SemaphoreInfo *) AcquireSemaphoreMemory(
 149     sizeof(*semaphore_info));
 150   if (semaphore_info == (SemaphoreInfo *) NULL)
 151     ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
 152   (void) ResetMagickMemory(semaphore_info,0,sizeof(SemaphoreInfo));
 153   /*
 154     Initialize the semaphore.
 155   */
 156 #if defined(MAGICKCORE_THREAD_SUPPORT)
 157   {
 158     int
 159       status;
 160
 161     pthread_mutexattr_t
 162       mutex_info;
 163
 164     status=pthread_mutexattr_init(&mutex_info);
 165     if (status != 0)
 166       {
 167         errno=status;
 168         ThrowFatalException(ResourceLimitFatalError,
 169           "UnableToInitializeSemaphore");
 170       }
 171 #if defined(MAGICKCORE_DEBUG)
 172 #if defined(PTHREAD_MUTEX_ERRORCHECK)
 173     status=pthread_mutex_settype(&mutex_info,PTHREAD_MUTEX_ERRORCHECK);
 174     if (status != 0)
 175       {
 176         errno=status;
 177         ThrowFatalException(ResourceLimitFatalError,
 178           "UnableToInitializeSemaphore");
 179       }
 180 #endif
 181 #endif
 182     status=pthread_mutex_init(&semaphore_info->mutex,&mutex_info);
 183     if (status != 0)
 184       {
 185         errno=status;
 186         ThrowFatalException(ResourceLimitFatalError,
 187           "UnableToInitializeSemaphore");
 188       }
 189     status=pthread_mutexattr_destroy(&mutex_info);
 190     if (status != 0)
 191       {
 192         errno=status;
 193         ThrowFatalException(ResourceLimitFatalError,
 194           "UnableToInitializeSemaphore");
 195       }
 196   }
 197 #elif defined(MAGICKCORE_HAVE_WINTHREADS)
 198   {
 199     int
 200       status;
 201
 202     status=InitializeCriticalSectionAndSpinCount(&semaphore_info->mutex,0x0400);
 203     if (status == 0)
 204       {
 205         errno=status;
 206         ThrowFatalException(ResourceLimitFatalError,
 207           "UnableToInitializeSemaphore");
 208        }
 209   }
 210 #endif
 211   semaphore_info->id=GetMagickThreadId();
 212   semaphore_info->reference_count=0;
 213   semaphore_info->signature=MagickSignature;
 214   return(semaphore_info);
 215 }
 216 \f
 217 /*
 218 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 219 %                                                                             %
 220 %                                                                             %
 221 %                                                                             %
 222 %   D e s t r o y S e m a p h o r e I n f o                                   %
 223 %                                                                             %
 224 %                                                                             %
 225 %                                                                             %
 226 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 227 %
 228 %  DestroySemaphoreInfo() destroys a semaphore.
 229 %
 230 %  The format of the DestroySemaphoreInfo method is:
 231 %
 232 %      void DestroySemaphoreInfo(SemaphoreInfo **semaphore_info)
 233 %
 234 %  A description of each parameter follows:
 235 %
 236 %    o semaphore_info: Specifies a pointer to an SemaphoreInfo structure.
 237 %
 238 */
 239 MagickExport void DestroySemaphoreInfo(SemaphoreInfo **semaphore_info)
 240 {
 241   assert(semaphore_info != (SemaphoreInfo **) NULL);
 242   assert((*semaphore_info) != (SemaphoreInfo *) NULL);
 243   assert((*semaphore_info)->signature == MagickSignature);
 244   LockMagickMutex();
 245 #if defined(MAGICKCORE_THREAD_SUPPORT)
 246   {
 247     int
 248       status;
 249
 250     status=pthread_mutex_destroy(&(*semaphore_info)->mutex);
 251     if (status != 0)
 252       {
 253         errno=status;
 254         ThrowFatalException(ResourceLimitFatalError,"UnableToDestroySemaphore");
 255       }
 256   }
 257 #elif defined(MAGICKCORE_HAVE_WINTHREADS)
 258   DeleteCriticalSection(&(*semaphore_info)->mutex);
 259 #endif
 260   (*semaphore_info)->signature=(~MagickSignature);
 261   free(*semaphore_info);
 262   *semaphore_info=(SemaphoreInfo *) NULL;
 263   UnlockMagickMutex();
 264 }
 265 \f
 266 /*
 267 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 268 %                                                                             %
 269 %                                                                             %
 270 %                                                                             %
 271 %   L o c k S e m a p h o r e I n f o                                         %
 272 %                                                                             %
 273 %                                                                             %
 274 %                                                                             %
 275 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 276 %
 277 %  LockSemaphoreInfo() locks a semaphore.
 278 %
 279 %  The format of the LockSemaphoreInfo method is:
 280 %
 281 %      void LockSemaphoreInfo(SemaphoreInfo *semaphore_info)
 282 %
 283 %  A description of each parameter follows:
 284 %
 285 %    o semaphore_info: Specifies a pointer to an SemaphoreInfo structure.
 286 %
 287 */
 288 MagickExport void LockSemaphoreInfo(SemaphoreInfo *semaphore_info)
 289 {
 290   assert(semaphore_info != (SemaphoreInfo *) NULL);
 291   assert(semaphore_info->signature == MagickSignature);
 292 #if defined(MAGICKCORE_THREAD_SUPPORT)
 293   {
 294     int
 295       status;
 296
 297     status=pthread_mutex_lock(&semaphore_info->mutex);
 298     if (status != 0)
 299       {
 300         errno=status;
 301         ThrowFatalException(ResourceLimitFatalError,"UnableToLockSemaphore");
 302       }
 303   }
 304 #elif defined(MAGICKCORE_HAVE_WINTHREADS)
 305   EnterCriticalSection(&semaphore_info->mutex);
 306 #endif
 307 #if defined(MAGICKCORE_DEBUG)
 308   if ((semaphore_info->reference_count > 0) &&
 309       (IsMagickThreadEqual(semaphore_info->id) != MagickFalse))
 310     {
 311       (void) FormatLocaleFile(stderr,"Warning: unexpected recursive lock!\n");
 312       (void) fflush(stderr);
 313     }
 314 #endif
 315   semaphore_info->id=GetMagickThreadId();
 316   semaphore_info->reference_count++;
 317 }
 318 \f
 319 /*
 320 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 321 %                                                                             %
 322 %                                                                             %
 323 %                                                                             %
 324 %   R e l i n g u i s h S e m a p h o r e I n f o                             %
 325 %                                                                             %
 326 %                                                                             %
 327 %                                                                             %
 328 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 329 %
 330 %  RelinquishSemaphoreInfo() relinquishes a semaphore.
 331 %
 332 %  The format of the RelinquishSemaphoreInfo method is:
 333 %
 334 %      RelinquishSemaphoreInfo(SemaphoreInfo *semaphore_info)
 335 %
 336 %  A description of each parameter follows:
 337 %
 338 %    o semaphore_info: Specifies a pointer to an SemaphoreInfo structure.
 339 %
 340 */
 341 MagickExport void RelinquishSemaphoreInfo(SemaphoreInfo *semaphore_info)
 342 {
 343   assert(semaphore_info != (SemaphoreInfo *) NULL);
 344   assert(semaphore_info->signature == MagickSignature);
 345   UnlockSemaphoreInfo(semaphore_info);
 346 }
 347 \f
 348 /*
 349 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 350 %                                                                             %
 351 %                                                                             %
 352 %                                                                             %
 353 %   S e m a p h o r e C o m p o n e n t G e n e s i s                         %
 354 %                                                                             %
 355 %                                                                             %
 356 %                                                                             %
 357 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 358 %
 359 %  SemaphoreComponentGenesis() instantiates the semaphore environment.
 360 %
 361 %  The format of the SemaphoreComponentGenesis method is:
 362 %
 363 %      MagickBooleanType SemaphoreComponentGenesis(void)
 364 %
 365 */
 366 MagickPrivate MagickBooleanType SemaphoreComponentGenesis(void)
 367 {
 368   LockMagickMutex();
 369   UnlockMagickMutex();
 370   return(MagickTrue);
 371 }
 372 \f
 373 /*
 374 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 375 %                                                                             %
 376 %                                                                             %
 377 %                                                                             %
 378 %   S e m a p h o r e C o m p o n e n t T e r m i n u s                       %
 379 %                                                                             %
 380 %                                                                             %
 381 %                                                                             %
 382 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 383 %
 384 %  SemaphoreComponentTerminus() destroys the semaphore component.
 385 %
 386 %  The format of the SemaphoreComponentTerminus method is:
 387 %
 388 %      SemaphoreComponentTerminus(void)
 389 %
 390 */
 391 MagickPrivate void SemaphoreComponentTerminus(void)
 392 {
 393 }
 394 \f
 395 /*
 396 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 397 %                                                                             %
 398 %                                                                             %
 399 %                                                                             %
 400 %   U n l o c k S e m a p h o r e I n f o                                     %
 401 %                                                                             %
 402 %                                                                             %
 403 %                                                                             %
 404 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 405 %
 406 %  UnlockSemaphoreInfo() unlocks a semaphore.
 407 %
 408 %  The format of the UnlockSemaphoreInfo method is:
 409 %
 410 %      void UnlockSemaphoreInfo(SemaphoreInfo *semaphore_info)
 411 %
 412 %  A description of each parameter follows:
 413 %
 414 %    o semaphore_info: Specifies a pointer to an SemaphoreInfo structure.
 415 %
 416 */
 417 MagickExport void UnlockSemaphoreInfo(SemaphoreInfo *semaphore_info)
 418 {
 419   assert(semaphore_info != (SemaphoreInfo *) NULL);
 420   assert(semaphore_info->signature == MagickSignature);
 421 #if defined(MAGICKCORE_DEBUG)
 422   assert(IsMagickThreadEqual(semaphore_info->id) != MagickFalse);
 423   if (semaphore_info->reference_count == 0)
 424     {
 425       (void) FormatLocaleFile(stderr,
 426         "Warning: semaphore lock already unlocked!\n");
 427       (void) fflush(stderr);
 428       return;
 429     }
 430   semaphore_info->reference_count--;
 431 #endif
 432 #if defined(MAGICKCORE_THREAD_SUPPORT)
 433   {
 434     int
 435       status;
 436
 437     status=pthread_mutex_unlock(&semaphore_info->mutex);
 438     if (status != 0)
 439       {
 440         errno=status;
 441         ThrowFatalException(ResourceLimitFatalError,"UnableToUnlockSemaphore");
 442       }
 443   }
 444 #elif defined(MAGICKCORE_HAVE_WINTHREADS)
 445   LeaveCriticalSection(&semaphore_info->mutex);
 446 #endif
 447 }