/*

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%        SSSSS  EEEEE  M   M   AAA   PPPP   H   H   OOO   RRRR   EEEEE        %

%        SS     E      MM MM  A   A  P   P  H   H  O   O  R   R  E            %

%         SSS   EEE    M M M  AAAAA  PPPP   HHHHH  O   O  RRRR   EEE          %

%           SS  E      M   M  A   A  P      H   H  O   O  R R    E            %

%        SSSSS  EEEEE  M   M  A   A  P      H   H   OOO   R  R   EEEEE        %

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%                                                                             %

%                        MagickCore Semaphore Methods                         %

%                                                                             %

%                              Software Design                                %

%                             William Radcliffe                               %

%                                   Cristy                                    %

%                                 June 2000                                   %

%                                                                             %

%                                                                             %

%  Copyright @ 1999 ImageMagick Studio LLC, a non-profit organization         %

%  dedicated to making software imaging solutions freely available.           %

%                                                                             %

%  You may not use this file except in compliance with the License.  You may  %

%  obtain a copy of the License at                                            %

%                                                                             %

%    https://imagemagick.org/license/                                         %

%                                                                             %

%  Unless required by applicable law or agreed to in writing, software        %

%  distributed under the License is distributed on an "AS IS" BASIS,          %

%  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   %

%  See the License for the specific language governing permissions and        %

%  limitations under the License.                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%

%

*/

/*

  Include declarations.

*/

#include "MagickCore/studio.h"

#include "MagickCore/exception.h"

#include "MagickCore/exception-private.h"

#include "MagickCore/memory_.h"

#include "MagickCore/memory-private.h"

#include "MagickCore/mutex.h"

#include "MagickCore/semaphore.h"

#include "MagickCore/semaphore-private.h"

#include "MagickCore/string_.h"

#include "MagickCore/thread_.h"

#include "MagickCore/thread-private.h"

#include "MagickCore/utility-private.h"

/*

  Struct declarations.

*/

struct SemaphoreInfo

{

  MagickMutexType

    mutex;

  MagickThreadType

    id;

  ssize_t

    reference_count;

  size_t

    signature;

};

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

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%                                                                             %

%   A c t i v a t e S e m a p h o r e I n f o                                 %

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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  ActivateSemaphoreInfo() activates a semaphore under protection of a mutex

%  to ensure only one thread allocates the semaphore.

%

%  The format of the ActivateSemaphoreInfo method is:

%

%      void ActivateSemaphoreInfo(SemaphoreInfo **semaphore_info)

%

%  A description of each parameter follows:

%

%    o semaphore_info: Specifies a pointer to an SemaphoreInfo structure.

%

*/

MagickExport void ActivateSemaphoreInfo(SemaphoreInfo **semaphore_info)

{

  assert(semaphore_info != (SemaphoreInfo **) NULL);

  if (*semaphore_info == (SemaphoreInfo *) NULL)

    {

      LockMagickMutex();

      if (*semaphore_info == (SemaphoreInfo *) NULL)

        *semaphore_info=AcquireSemaphoreInfo();

      UnlockMagickMutex();

    }

}

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%                                                                             %

%   A c q u i r e S e m a p h o r e I n f o                                   %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  AcquireSemaphoreInfo() initializes the SemaphoreInfo structure.

%

%  The format of the AcquireSemaphoreInfo method is:

%

%      SemaphoreInfo *AcquireSemaphoreInfo(void)

%

*/

static void *AcquireSemaphoreMemory(const size_t count,const size_t quantum)

{

#define AlignedExtent(size,alignment) \

  (((size)+((alignment)-1)) & (size_t) ~((alignment)-1))

  size_t

    alignment,

    extent,

    size;

  void

    *memory;

  size=count*quantum;

  if ((count == 0) || (quantum != (size/count)))

    {

      errno=ENOMEM;

      return((void *) NULL);

    }

  memory=NULL;

  alignment=CACHE_LINE_SIZE;

  extent=AlignedExtent(size,CACHE_LINE_SIZE);

  if ((size == 0) || (alignment < sizeof(void *)) || (extent < size))

    return((void *) NULL);

#if defined(MAGICKCORE_HAVE_POSIX_MEMALIGN)

  if (posix_memalign(&memory,alignment,extent) != 0)

    memory=NULL;

#elif defined(MAGICKCORE_HAVE__ALIGNED_MALLOC)

   memory=_aligned_malloc(extent,alignment);

#else

  {

    void

      *p;

    extent=(size+alignment-1)+sizeof(void *);

    if (extent > size)

      {

        p=malloc(extent);

        if (p != NULL)

          {

            memory=(void *) AlignedExtent((size_t) p+sizeof(void *),alignment);

            *((void **) memory-1)=p;

          }

      }

  }

#endif

  return(memory);

}

static void *RelinquishSemaphoreMemory(void *memory)

{

  if (memory == (void *) NULL)

    return((void *) NULL);

#if defined(MAGICKCORE_HAVE_POSIX_MEMALIGN)

  free(memory);

#elif defined(MAGICKCORE_HAVE__ALIGNED_MALLOC)

  _aligned_free(memory);

#else

  free(*((void **) memory-1));

#endif

  return(NULL);

}

MagickExport SemaphoreInfo *AcquireSemaphoreInfo(void)

{

  SemaphoreInfo

    *semaphore_info;

  /*

    Acquire semaphore.

  */

  semaphore_info=(SemaphoreInfo *) AcquireSemaphoreMemory(1,

    sizeof(*semaphore_info));

  if (semaphore_info == (SemaphoreInfo *) NULL)

    ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");

  (void) memset(semaphore_info,0,sizeof(SemaphoreInfo));

  /*

    Initialize the semaphore.

  */

#if defined(MAGICKCORE_OPENMP_SUPPORT)

  omp_init_lock((omp_lock_t *) &semaphore_info->mutex);

#elif defined(MAGICKCORE_THREAD_SUPPORT)

  {

    int

      status;

    pthread_mutexattr_t

      mutex_info;

    status=pthread_mutexattr_init(&mutex_info);

    if (status != 0)

      {

        errno=status;

        perror("unable to initialize mutex attributes");

        _exit(1);

      }

#if defined(MAGICKCORE_DEBUG)

#if defined(PTHREAD_MUTEX_ERRORCHECK)

    status=pthread_mutex_settype(&mutex_info,PTHREAD_MUTEX_ERRORCHECK);

    if (status != 0)

      {

        errno=status;

        perror("unable to set mutex type");

        _exit(1);

      }

#endif

#endif

    status=pthread_mutex_init(&semaphore_info->mutex,&mutex_info);

    if (status != 0)

      {

        errno=status;

        perror("unable to initialize mutex");

        _exit(1);

      }

    status=pthread_mutexattr_destroy(&mutex_info);

    if (status != 0)

      {

        errno=status;

        perror("unable to destroy mutex attributes");

        _exit(1);

      }

  }

#elif defined(MAGICKCORE_WINDOWS_SUPPORT)

  {

    int

      status;

    status=InitializeCriticalSectionAndSpinCount(&semaphore_info->mutex,0x0400);

    if (status == 0)

      {

        errno=status;

        perror("unable to initialize critical section");

        _exit(1);

      }

  }

#endif

  semaphore_info->id=GetMagickThreadId();

  semaphore_info->reference_count=0;

  semaphore_info->signature=MagickCoreSignature;

  return(semaphore_info);

}

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%                                                                             %

%   L o c k S e m a p h o r e I n f o                                         %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  LockSemaphoreInfo() locks a semaphore.

%

%  The format of the LockSemaphoreInfo method is:

%

%      void LockSemaphoreInfo(SemaphoreInfo *semaphore_info)

%

%  A description of each parameter follows:

%

%    o semaphore_info: Specifies a pointer to an SemaphoreInfo structure.

%

*/

MagickExport void LockSemaphoreInfo(SemaphoreInfo *semaphore_info)

{

  assert(semaphore_info != (SemaphoreInfo *) NULL);

  assert(semaphore_info->signature == MagickCoreSignature);

#if defined(MAGICKCORE_DEBUG)

  if ((semaphore_info->reference_count > 0) &&

      (IsMagickThreadEqual(semaphore_info->id) != MagickFalse))

    {

      (void) FormatLocaleFile(stderr,"Warning: unexpected recursive lock!\n");

      (void) fflush(stderr);

    }

#endif

#if defined(MAGICKCORE_OPENMP_SUPPORT)

  omp_set_lock((omp_lock_t *) &semaphore_info->mutex);

#elif defined(MAGICKCORE_THREAD_SUPPORT)

  {

    int

      status;

    status=pthread_mutex_lock(&semaphore_info->mutex);

    if (status != 0)

      {

        errno=status;

        perror("unable to lock mutex");

        _exit(1);

      }

  }

#elif defined(MAGICKCORE_WINDOWS_SUPPORT)

  EnterCriticalSection(&semaphore_info->mutex);

#endif

#if defined(MAGICKCORE_DEBUG)

  semaphore_info->id=GetMagickThreadId();

  semaphore_info->reference_count++;

#endif

}

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%                                                                             %

%   R e l i n q u i s h S e m a p h o r e I n f o                             %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  RelinquishSemaphoreInfo() destroys a semaphore.

%

%  The format of the RelinquishSemaphoreInfo method is:

%

%      void RelinquishSemaphoreInfo(SemaphoreInfo **semaphore_info)

%

%  A description of each parameter follows:

%

%    o semaphore_info: Specifies a pointer to an SemaphoreInfo structure.

%

*/

MagickExport void RelinquishSemaphoreInfo(SemaphoreInfo **semaphore_info)

{

  assert(semaphore_info != (SemaphoreInfo **) NULL);

  assert((*semaphore_info) != (SemaphoreInfo *) NULL);

  assert((*semaphore_info)->signature == MagickCoreSignature);

  LockMagickMutex();

#if defined(MAGICKCORE_OPENMP_SUPPORT)

  omp_destroy_lock((omp_lock_t *) &(*semaphore_info)->mutex);

#elif defined(MAGICKCORE_THREAD_SUPPORT)

  {

    int

      status;

    status=pthread_mutex_destroy(&(*semaphore_info)->mutex);

    if (status != 0)

      {

        errno=status;

        perror("unable to destroy mutex");

        _exit(1);

      }

  }

#elif defined(MAGICKCORE_WINDOWS_SUPPORT)

  DeleteCriticalSection(&(*semaphore_info)->mutex);

#endif

  (*semaphore_info)->signature=(~MagickCoreSignature);

  *semaphore_info=(SemaphoreInfo *) RelinquishSemaphoreMemory(*semaphore_info);

  UnlockMagickMutex();

}

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%                                                                             %

%   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                         %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  SemaphoreComponentGenesis() instantiates the semaphore environment.

%

%  The format of the SemaphoreComponentGenesis method is:

%

%      MagickBooleanType SemaphoreComponentGenesis(void)

%

*/

MagickPrivate MagickBooleanType SemaphoreComponentGenesis(void)

{

  InitializeMagickMutex();

  return(MagickTrue);

}

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%                                                                             %

%   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                       %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  SemaphoreComponentTerminus() destroys the semaphore component.

%

%  The format of the SemaphoreComponentTerminus method is:

%

%      SemaphoreComponentTerminus(void)

%

*/

MagickPrivate void SemaphoreComponentTerminus(void)

{

  DestroyMagickMutex();

}

/*

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%                                                                             %

%                                                                             %

%                                                                             %

%   U n l o c k S e m a p h o r e I n f o                                     %

%                                                                             %

%                                                                             %

%                                                                             %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%

%  UnlockSemaphoreInfo() unlocks a semaphore.

%

%  The format of the UnlockSemaphoreInfo method is:

%

%      void UnlockSemaphoreInfo(SemaphoreInfo *semaphore_info)

%

%  A description of each parameter follows:

%

%    o semaphore_info: Specifies a pointer to an SemaphoreInfo structure.

%

*/

MagickExport void UnlockSemaphoreInfo(SemaphoreInfo *semaphore_info)

{

  assert(semaphore_info != (SemaphoreInfo *) NULL);

  assert(semaphore_info->signature == MagickCoreSignature);

#if defined(MAGICKCORE_DEBUG)

  assert(IsMagickThreadEqual(semaphore_info->id) != MagickFalse);

  if (semaphore_info->reference_count == 0)

    {

      (void) FormatLocaleFile(stderr,

        "Warning: semaphore lock already unlocked!\n");

      (void) fflush(stderr);

      return;

    }

  semaphore_info->reference_count--;

#endif

#if defined(MAGICKCORE_OPENMP_SUPPORT)

  omp_unset_lock((omp_lock_t *) &semaphore_info->mutex);

#elif defined(MAGICKCORE_THREAD_SUPPORT)

  {

    int

      status;

    status=pthread_mutex_unlock(&semaphore_info->mutex);

    if (status != 0)

      {

        errno=status;

        perror("unable to unlock mutex");

        _exit(1);

      }

  }

#elif defined(MAGICKCORE_WINDOWS_SUPPORT)

  LeaveCriticalSection(&semaphore_info->mutex);

#endif

}