C++ LockSemaphoreInfo函数代码示例

static MagickBooleanType SetPolicyValue(const PolicyDomain domain,
  const char *name,const char *value)
{
  MagickBooleanType
    status;

  register PolicyInfo
    *p;

  status=MagickTrue;
  LockSemaphoreInfo(policy_semaphore);
  ResetLinkedListIterator(policy_cache);
  p=(PolicyInfo *) GetNextValueInLinkedList(policy_cache);
  while (p != (PolicyInfo *) NULL)
  {
    if ((p->domain == domain) && (LocaleCompare(name,p->name) == 0))
      break;
    p=(PolicyInfo *) GetNextValueInLinkedList(policy_cache);
  }
  if (p != (PolicyInfo *) NULL)
    {
      if (p->value != (char *) NULL)
        p->value=DestroyString(p->value);
    }
  else
    {
      p=(PolicyInfo *) AcquireCriticalMemory(sizeof(*p));
      (void) memset(p,0,sizeof(*p));
      p->exempt=MagickFalse;
      p->signature=MagickCoreSignature;
      p->domain=domain;
      p->name=ConstantString(name);
      status=AppendValueToLinkedList(policy_cache,p);
    }
  p->value=ConstantString(value);
  UnlockSemaphoreInfo(policy_semaphore);
  if (status == MagickFalse)
    p=(PolicyInfo *) RelinquishMagickMemory(p);
  return(status);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
+   I n i t i a l i z e L o c a l e L i s t                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  InitializeLocaleList() initializes the locale list.
%
%  The format of the InitializeLocaleList method is:
%
%      MagickBooleanType InitializeLocaleList(ExceptionInfo *exception)
%
%  A description of each parameter follows.
%
%    o exception: return any errors or warnings in this structure.
%
*/
static MagickBooleanType InitializeLocaleList(ExceptionInfo *exception)
{
  if ((locale_list == (SplayTreeInfo *) NULL) &&
      (instantiate_locale == MagickFalse))
    {
      if (locale_semaphore == (SemaphoreInfo *) NULL)
        AcquireSemaphoreInfo(&locale_semaphore);
      LockSemaphoreInfo(locale_semaphore);
      if ((locale_list == (SplayTreeInfo *) NULL) &&
          (instantiate_locale == MagickFalse))
        {
          char
            *locale;

          register const char
            *p;

          locale=(char *) NULL;
          p=setlocale(LC_CTYPE,(const char *) NULL);
          if (p != (const char *) NULL)
            locale=ConstantString(p);
          if (locale == (char *) NULL)
            locale=GetEnvironmentValue("LC_ALL");
          if (locale == (char *) NULL)
            locale=GetEnvironmentValue("LC_MESSAGES");
          if (locale == (char *) NULL)
            locale=GetEnvironmentValue("LC_CTYPE");
          if (locale == (char *) NULL)
            locale=GetEnvironmentValue("LANG");
          if (locale == (char *) NULL)
            locale=ConstantString("C");
          (void) LoadLocaleLists(LocaleFilename,locale,exception);
          locale=DestroyString(locale);
          instantiate_locale=MagickTrue;
        }
      UnlockSemaphoreInfo(locale_semaphore);
    }
  return(locale_list != (SplayTreeInfo *) NULL ? MagickTrue : MagickFalse);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
+   D e s t r o y M a g i c k M e m o r y                                     %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  DestroyMagickMemory() deallocates memory associated with the memory manager.
%
%  The format of the DestroyMagickMemory method is:
%
%      DestroyMagickMemory(void)
%
*/
MagickExport void DestroyMagickMemory(void)
{
#if defined(MAGICKCORE_ZERO_CONFIGURATION_SUPPORT)
  register ssize_t
    i;

  if (memory_semaphore == (SemaphoreInfo *) NULL)
    ActivateSemaphoreInfo(&memory_semaphore);
  LockSemaphoreInfo(memory_semaphore);
  for (i=0; i < (ssize_t) memory_pool.number_segments; i++)
    if (memory_pool.segments[i]->mapped == MagickFalse)
      memory_methods.destroy_memory_handler(
        memory_pool.segments[i]->allocation);
    else
      (void) UnmapBlob(memory_pool.segments[i]->allocation,
        memory_pool.segments[i]->length);
  free_segments=(DataSegmentInfo *) NULL;
  (void) ResetMagickMemory(&memory_pool,0,sizeof(memory_pool));
  UnlockSemaphoreInfo(memory_semaphore);
  DestroySemaphoreInfo(&memory_semaphore);
#endif
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   A c q u i r e S e m a p h o r e I n f o                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  AcquireSemaphoreInfo() acquires a semaphore.
%
%  The format of the AcquireSemaphoreInfo method is:
%
%      void AcquireSemaphoreInfo(SemaphoreInfo **semaphore_info)
%
%  A description of each parameter follows:
%
%    o semaphore_info: Specifies a pointer to an SemaphoreInfo structure.
%
*/
MagickExport void AcquireSemaphoreInfo(SemaphoreInfo **semaphore_info)
{
  assert(semaphore_info != (SemaphoreInfo **) NULL);
#if defined(MAGICKCORE_HAVE_PTHREAD)
  if (pthread_mutex_lock(&semaphore_mutex) != 0)
    (void) fprintf(stderr,"pthread_mutex_lock failed %s\n",
      GetExceptionMessage(errno));
#elif defined(MAGICKORE_HAVE_WINTHREADS)
  while (InterlockedCompareExchange(&semaphore_mutex,1L,0L) != 0)
    Sleep(10);
#endif
  if (*semaphore_info == (SemaphoreInfo *) NULL)
    *semaphore_info=AllocateSemaphoreInfo();
#if defined(MAGICKCORE_HAVE_PTHREAD)
  if (pthread_mutex_unlock(&semaphore_mutex) != 0)
    (void) fprintf(stderr,"pthread_mutex_unlock failed %s\n",
      GetExceptionMessage(errno));
#elif defined(MAGICKORE_HAVE_WINTHREADS)
  InterlockedExchange(&semaphore_mutex,0L);
#endif
  (void) LockSemaphoreInfo(*semaphore_info);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%  L i s t M a g i c k R e s o u r c e I n f o                                %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  ListMagickResourceInfo() lists the resource info to a file.
%
%  The format of the ListMagickResourceInfo method is:
%
%      MagickBooleanType ListMagickResourceInfo(FILE *file,
%        ExceptionInfo *exception)
%
%  A description of each parameter follows.
%
%    o file:  An pointer to a FILE.
%
%    o exception: return any errors or warnings in this structure.
%
*/
MagickExport MagickBooleanType ListMagickResourceInfo(FILE *file,
  ExceptionInfo *magick_unused(exception))
{
  char
    area_limit[MaxTextExtent],
    disk_limit[MaxTextExtent],
    map_limit[MaxTextExtent],
    memory_limit[MaxTextExtent],
    time_limit[MaxTextExtent];

  if (file == (const FILE *) NULL)
    file=stdout;
  if (resource_semaphore == (SemaphoreInfo *) NULL)
    AcquireSemaphoreInfo(&resource_semaphore);
  LockSemaphoreInfo(resource_semaphore);
  (void) FormatMagickSize(resource_info.area_limit,MagickFalse,area_limit);
  (void) FormatMagickSize(resource_info.memory_limit,MagickTrue,memory_limit);
  (void) FormatMagickSize(resource_info.map_limit,MagickTrue,map_limit);
  (void) CopyMagickString(disk_limit,"unlimited",MaxTextExtent);
  if (resource_info.disk_limit != MagickResourceInfinity)
    (void) FormatMagickSize(resource_info.disk_limit,MagickTrue,disk_limit);
  (void) CopyMagickString(time_limit,"unlimited",MaxTextExtent);
  if (resource_info.time_limit != MagickResourceInfinity)
    (void) FormatLocaleString(time_limit,MaxTextExtent,"%.20g",(double)
      ((MagickOffsetType) resource_info.time_limit));
  (void) FormatLocaleFile(file,"  File       Area     Memory        Map"
    "       Disk   Thread  Throttle       Time\n");
  (void) FormatLocaleFile(file,
    "--------------------------------------------------------"
    "------------------------\n");
  (void) FormatLocaleFile(file,"%6g %10s %10s %10s %10s %8g  %8g %10s\n",
    (double) ((MagickOffsetType) resource_info.file_limit),area_limit,
    memory_limit,map_limit,disk_limit,(double) ((MagickOffsetType)
    resource_info.thread_limit),(double) ((MagickOffsetType)
    resource_info.throttle_limit),time_limit);
  (void) fflush(file);
  UnlockSemaphoreInfo(resource_semaphore);
  return(MagickTrue);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   T h r o w E x c e p t i o n                                               %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  ThrowException() throws an exception with the specified severity code,
%  reason, and optional description.
%
%  The format of the ThrowException method is:
%
%      MagickBooleanType ThrowException(ExceptionInfo *exception,
%        const ExceptionType severity,const char *reason,
%        const char *description)
%
%  A description of each parameter follows:
%
%    o exception: the exception info.
%
%    o severity: the severity of the exception.
%
%    o reason: the reason for the exception.
%
%    o description: the exception description.
%
*/
MagickExport MagickBooleanType ThrowException(ExceptionInfo *exception,
  const ExceptionType severity,const char *reason,const char *description)
{
  register ExceptionInfo
    *p;

  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  LockSemaphoreInfo(exception->semaphore);
  p=(ExceptionInfo *) GetLastValueInLinkedList((LinkedListInfo *)
    exception->exceptions);
  if ((p != (ExceptionInfo *) NULL) && (p->severity == severity) &&
      (LocaleCompare(exception->reason,reason) == 0) &&
      (LocaleCompare(exception->description,description) == 0))
    {
      UnlockSemaphoreInfo(exception->semaphore);
      return(MagickTrue);
    }
  p=(ExceptionInfo *) AcquireMagickMemory(sizeof(*p));
  if (p == (ExceptionInfo *) NULL)
    {
      UnlockSemaphoreInfo(exception->semaphore);
      ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
    }
  (void) ResetMagickMemory(p,0,sizeof(*p));
  p->severity=severity;
  if (reason != (const char *) NULL)
    p->reason=ConstantString(reason);
  if (description != (const char *) NULL)
    p->description=ConstantString(description);
  p->signature=MagickSignature;
  (void) AppendValueToLinkedList((LinkedListInfo *) exception->exceptions,p);
  exception->severity=p->severity;
  exception->reason=p->reason;
  exception->description=p->description;
  UnlockSemaphoreInfo(exception->semaphore);
  return(MagickTrue);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
+   G e t M a g i c I n f o                                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  GetMagicInfo() searches the magic list for the specified name and if found
%  returns attributes for that magic.
%
%  The format of the GetMagicInfo method is:
%
%      const MagicInfo *GetMagicInfo(const unsigned char *magic,
%        const size_t length,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o magic: A binary string generally representing the first few characters
%      of the image file or blob.
%
%    o length: the length of the binary signature.
%
%    o exception: return any errors or warnings in this structure.
%
*/
MagickExport const MagicInfo *GetMagicInfo(const unsigned char *magic,
  const size_t length,ExceptionInfo *exception)
{
  register const MagicInfo
    *p;

  assert(exception != (ExceptionInfo *) NULL);
  if ((magic_list == (LinkedListInfo *) NULL) ||
      (instantiate_magic == MagickFalse))
    if (InitializeMagicList(exception) == MagickFalse)
      return((const MagicInfo *) NULL);
  if ((magic_list == (LinkedListInfo *) NULL) ||
      (IsLinkedListEmpty(magic_list) != MagickFalse))
    return((const MagicInfo *) NULL);
  if (magic == (const unsigned char *) NULL)
    return((const MagicInfo *) GetValueFromLinkedList(magic_list,0));
  if (length == 0)
    return((const MagicInfo *) NULL);
  /*
    Search for magic tag.
  */
  LockSemaphoreInfo(magic_semaphore);
  ResetLinkedListIterator(magic_list);
  p=(const MagicInfo *) GetNextValueInLinkedList(magic_list);
  while (p != (const MagicInfo *) NULL)
  {
    assert(p->offset >= 0);
    if (((size_t) (p->offset+p->length) <= length) &&
        (memcmp(magic+p->offset,p->magic,p->length) == 0))
      break;
    p=(const MagicInfo *) GetNextValueInLinkedList(magic_list);
  }
  if (p != (const MagicInfo *) NULL)
    (void) InsertValueInLinkedList(magic_list,0,
      RemoveElementByValueFromLinkedList(magic_list,p));
  UnlockSemaphoreInfo(magic_semaphore);
  return(p);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   D e s t r o y E x c e p t i o n I n f o                                   %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  DestroyExceptionInfo() deallocates memory associated with an exception.
%
%  The format of the DestroyExceptionInfo method is:
%
%      ExceptionInfo *DestroyExceptionInfo(ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o exception: the exception info.
%
*/
MagickExport ExceptionInfo *DestroyExceptionInfo(ExceptionInfo *exception)
{
  MagickBooleanType
    relinquish;

  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  if (exception->semaphore == (SemaphoreInfo *) NULL)
    AcquireSemaphoreInfo(&exception->semaphore);
  LockSemaphoreInfo(exception->semaphore);
  exception->severity=UndefinedException;
  if (exception->exceptions != (void *) NULL)
    exception->exceptions=(void *) DestroyLinkedList((LinkedListInfo *)
      exception->exceptions,DestroyExceptionElement);
  relinquish=exception->relinquish;
  if (exception->relinquish != MagickFalse)
    exception->signature=(~MagickSignature);
  UnlockSemaphoreInfo(exception->semaphore);
  DestroySemaphoreInfo(&exception->semaphore);
  if (relinquish != MagickFalse)
    exception=(ExceptionInfo *) RelinquishMagickMemory(exception);
  return(exception);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   L i n k e d L i s t T o A r r a y                                         %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  LinkedListToArray() converts the linked-list to an array.
%
%  The format of the LinkedListToArray method is:
%
%      MagickBooleanType LinkedListToArray(LinkedListInfo *list_info,
%        void **array)
%
%  A description of each parameter follows:
%
%    o list_info: the linked-list info.
%
%    o array: the array.
%
*/
MagickExport MagickBooleanType LinkedListToArray(LinkedListInfo *list_info,
  void **array)
{
  register ElementInfo
    *next;

  register ssize_t
    i;

  assert(list_info != (LinkedListInfo *) NULL);
  assert(list_info->signature == MagickCoreSignature);
  if (array == (void **) NULL)
    return(MagickFalse);
  LockSemaphoreInfo(list_info->semaphore);
  next=list_info->head;
  for (i=0; next != (ElementInfo *) NULL; i++)
  {
    array[i]=next->value;
    next=next->next;
  }
  UnlockSemaphoreInfo(list_info->semaphore);
  return(MagickTrue);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   G e t M a g i c k I n f o                                                 %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  GetMagickInfo() returns a pointer MagickInfo structure that matches
%  the specified name.  If name is NULL, the head of the image format list
%  is returned. It is not safe to traverse the list by using the previous and
%  next pointers in the MagickInfo structure since the list contents or order
%  may be altered while the list is being traversed. If the list must be
%  traversed, access it via the GetMagickInfoArray function instead.
%
%  If GraphicsMagick has not been initialized via InitializeMagick()
%  then this function will not work.
%
%  The format of the GetMagickInfo method is:
%
%     const MagickInfo *GetMagickInfo(const char *name,ExceptionInfo *exception)
%
%  A description of each parameter follows:
%
%    o name: The image format we are looking for.
%
%    o exception: Return any errors or warnings in this structure.
%
%
*/
static MagickInfo *
GetMagickInfoEntryLocked(const char *name)
{
  register MagickInfo
    *p;

  LockSemaphoreInfo(magick_semaphore);

  p=magick_list;

  if ((name != (const char *) NULL) && (name[0] != '*'))
    {
      for (p=magick_list; p != (MagickInfo *) NULL; p=p->next)
        if (LocaleCompare(p->name,name) == 0)
          break;
      
      if (p != (MagickInfo *) NULL)
        if (p != magick_list)
          {
            /*
              Self-adjusting list.
            */
            if (p->previous != (MagickInfo *) NULL)
              p->previous->next=p->next;
            if (p->next != (MagickInfo *) NULL)
              p->next->previous=p->previous;
            p->previous=(MagickInfo *) NULL;
            p->next=magick_list;
            magick_list->previous=p;
            magick_list=p;
          }
    }

  UnlockSemaphoreInfo(magick_semaphore);

  return p;
}

MagickExport void ClearMagickException(ExceptionInfo *exception)
{
  register ExceptionInfo
    *p;

  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  if (exception->exceptions  == (void *) NULL)
    return;
  LockSemaphoreInfo(exception->semaphore);
  p=(ExceptionInfo *) RemoveLastElementFromLinkedList((LinkedListInfo *)
    exception->exceptions);
  while (p != (ExceptionInfo *) NULL)
  {
    (void) DestroyExceptionElement(p);
    p=(ExceptionInfo *) RemoveLastElementFromLinkedList((LinkedListInfo *)
      exception->exceptions);
  }
  exception->severity=UndefinedException;
  exception->reason=(char *) NULL;
  exception->description=(char *) NULL;
  UnlockSemaphoreInfo(exception->semaphore);
  errno=0;
}

int HasError(ExceptionInfo *exception) {
  register const ExceptionInfo *p;
  int result = 0;

  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  if (exception->exceptions  == (void *) NULL)
    return 0;
  if (exception->semaphore == (void *) NULL)
    return 0;

  LockSemaphoreInfo(exception->semaphore);
  ResetLinkedListIterator((LinkedListInfo *) exception->exceptions);
  p=(const ExceptionInfo *) GetNextValueInLinkedList((LinkedListInfo *)
    exception->exceptions);
  while (p != (const ExceptionInfo *) NULL) {
    if (p->severity >= ErrorException)
      result = 1;
    p=(const ExceptionInfo *) GetNextValueInLinkedList((LinkedListInfo *)
      exception->exceptions);
  }
  UnlockSemaphoreInfo(exception->semaphore);
	return result;
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   I n h e r i t E x c e p t i o n                                           %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  InheritException() inherits an exception from a related exception.
%
%  The format of the InheritException method is:
%
%      InheritException(ExceptionInfo *exception,const ExceptionInfo *relative)
%
%  A description of each parameter follows:
%
%    o exception: the exception info.
%
%    o relative: the related exception info.
%
*/
MagickExport void InheritException(ExceptionInfo *exception,
  const ExceptionInfo *relative)
{
  register const ExceptionInfo
    *p;

  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  assert(relative != (ExceptionInfo *) NULL);
  assert(relative->signature == MagickSignature);
  if (relative->exceptions == (void *) NULL)
    return;
  LockSemaphoreInfo(relative->semaphore);
  ResetLinkedListIterator((LinkedListInfo *) relative->exceptions);
  p=(const ExceptionInfo *) GetNextValueInLinkedList((LinkedListInfo *)
    relative->exceptions);
  while (p != (const ExceptionInfo *) NULL)
  {
    (void) ThrowException(exception,p->severity,p->reason,p->description);
    p=(const ExceptionInfo *) GetNextValueInLinkedList((LinkedListInfo *)
      relative->exceptions);
  }
  UnlockSemaphoreInfo(relative->semaphore);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%   G e t V a l u e F r o m L i n k e d L i s t                               %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  GetValueFromLinkedList() gets a value from the linked-list at the specified
%  location.
%
%  The format of the GetValueFromLinkedList method is:
%
%      void *GetValueFromLinkedList(LinkedListInfo *list_info,
%        const size_t index)
%
%  A description of each parameter follows:
%
%    o list_info: the linked_list info.
%
%    o index: the list index.
%
*/
MagickExport void *GetValueFromLinkedList(LinkedListInfo *list_info,
  const size_t index)
{
  register ElementInfo
    *next;

  register ssize_t
    i;

  void
    *value;

  assert(list_info != (LinkedListInfo *) NULL);
  assert(list_info->signature == MagickCoreSignature);
  if (index >= list_info->elements)
    return((void *) NULL);
  LockSemaphoreInfo(list_info->semaphore);
  if (index == 0)
    {
      value=list_info->head->value;
      UnlockSemaphoreInfo(list_info->semaphore);
      return(value);
    }
  if (index == (list_info->elements-1))
    {
      value=list_info->tail->value;
      UnlockSemaphoreInfo(list_info->semaphore);
      return(value);
    }
  next=list_info->head;
  for (i=0; i < (ssize_t) index; i++)
    next=next->next;
  value=next->value;
  UnlockSemaphoreInfo(list_info->semaphore);
  return(value);
}

/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                             %
%                                                                             %
%                                                                             %
%    R e l i n q u i s h U n i q u e F i l e R e s o u r c e                  %
%                                                                             %
%                                                                             %
%                                                                             %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%  RelinquishUniqueFileResource() relinquishes a unique file resource.
%
%  The format of the RelinquishUniqueFileResource() method is:
%
%      MagickBooleanType RelinquishUniqueFileResource(const char *path)
%
%  A description of each parameter follows:
%
%    o name: the name of the temporary resource.
%
*/
MagickExport MagickBooleanType RelinquishUniqueFileResource(const char *path)
{
  char
    cache_path[MagickPathExtent];

  MagickBooleanType
    status;

  assert(path != (const char *) NULL);
  status=MagickFalse;
  (void) LogMagickEvent(ResourceEvent,GetMagickModule(),"%s",path);
  if (resource_semaphore == (SemaphoreInfo *) NULL)
    ActivateSemaphoreInfo(&resource_semaphore);
  LockSemaphoreInfo(resource_semaphore);
  if (temporary_resources != (SplayTreeInfo *) NULL)
    status=DeleteNodeFromSplayTree(temporary_resources, (const void *) path);
  UnlockSemaphoreInfo(resource_semaphore);
  (void) CopyMagickString(cache_path,path,MagickPathExtent);
  AppendImageFormat("cache",cache_path);
  (void) ShredFile(cache_path);
  if (status == MagickFalse)
    status=ShredFile(path);
  return(status);
}