/*

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

%                                                                             %

%                                                                             %

%                                                                             %

%                    M   M  EEEEE  M   M   OOO   RRRR   Y   Y                 %

%                    MM MM  E      MM MM  O   O  R   R   Y Y                  %

%                    M M M  EEE    M M M  O   O  RRRR     Y                   %

%                    M   M  E      M   M  O   O  R R      Y                   %

%                    M   M  EEEEE  M   M   OOO   R  R     Y                   %

%                                                                             %

%                                                                             %

%                     MagickCore Memory Allocation Methods                    %

%                                                                             %

%                              Software Design                                %

%                                   Cristy                                    %

%                                 July 1998                                   %

%                                                                             %

%                                                                             %

%  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.                                             %

%                                                                             %

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

%

%  We provide these memory allocators:

%

%    AcquireCriticalMemory(): allocate a small memory request with

%      AcquireMagickMemory(), however, on fail throw a fatal exception and exit.

%      Free the memory reserve with RelinquishMagickMemory().

%    AcquireAlignedMemory(): allocate a small memory request that is aligned

%      on a cache line.  On fail, return NULL for possible recovery.

%      Free the memory reserve with RelinquishMagickMemory().

%    AcquireMagickMemory()/ResizeMagickMemory(): allocate a small to medium

%      memory request, typically with malloc()/realloc(). On fail, return NULL

%      for possible recovery.  Free the memory reserve with

%      RelinquishMagickMemory().

%    AcquireQuantumMemory()/ResizeQuantumMemory(): allocate a small to medium

%      memory request.  This is a secure memory allocator as it accepts two

%      parameters, count and quantum, to ensure the request does not overflow.

%      It also check to ensure the request does not exceed the maximum memory

%      per the security policy.  Free the memory reserve with

%      RelinquishMagickMemory().

%    AcquireVirtualMemory(): allocate a large memory request either in heap,

%      memory-mapped, or memory-mapped on disk depending on whether heap

%      allocation fails or if the request exceeds the maximum memory policy.

%      Free the memory reserve with RelinquishVirtualMemory().

%    ResetMagickMemory(): fills the bytes of the memory area with a constant

%      byte.

%    

%  In addition, we provide hooks for your own memory constructor/destructors.

%  You can also utilize our internal custom allocator as follows: Segregate

%  our memory requirements from any program that calls our API.  This should

%  help reduce the risk of others changing our program state or causing memory

%  corruption.

%

%  Our custom memory allocation manager implements a best-fit allocation policy

%  using segregated free lists.  It uses a linear distribution of size classes

%  for lower sizes and a power of two distribution of size classes at higher

%  sizes.  It is based on the paper, "Fast Memory Allocation using Lazy Fits."

%  written by Yoo C. Chung.

%

%  By default, C's standard library is used (e.g. malloc);  use the

%  custom memory allocator by defining MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT

%  to allocate memory with private anonymous mapping rather than from the

%  heap.

%

*/

/*

  Include declarations.

*/

#include "MagickCore/studio.h"

#include "MagickCore/blob.h"

#include "MagickCore/blob-private.h"

#include "MagickCore/exception.h"

#include "MagickCore/exception-private.h"

#include "MagickCore/image-private.h"

#include "MagickCore/memory_.h"

#include "MagickCore/memory-private.h"

#include "MagickCore/policy.h"

#include "MagickCore/resource_.h"

#include "MagickCore/semaphore.h"

#include "MagickCore/string_.h"

#include "MagickCore/string-private.h"

#include "MagickCore/utility-private.h"

/*

  Define declarations.

*/

#define BlockFooter(block,size) \

  ((size_t *) ((char *) (block)+(size)-2*sizeof(size_t)))

#define BlockHeader(block)  ((size_t *) (block)-1)

#define BlockThreshold  1024

#define MaxBlockExponent  16

#define MaxBlocks ((BlockThreshold/(4*sizeof(size_t)))+MaxBlockExponent+1)

#define MaxSegments  1024

#define NextBlock(block)  ((char *) (block)+SizeOfBlock(block))

#define NextBlockInList(block)  (*(void **) (block))

#define PreviousBlock(block)  ((char *) (block)-(*((size_t *) (block)-2)))

#define PreviousBlockBit  0x01

#define PreviousBlockInList(block)  (*((void **) (block)+1))

#define SegmentSize  (2*1024*1024)

#define SizeMask  (~0x01)

#define SizeOfBlock(block)  (*BlockHeader(block) & SizeMask)

/*

  Typedef declarations.

*/

typedef enum

{

  UndefinedVirtualMemory,

  AlignedVirtualMemory,

  MapVirtualMemory,

  UnalignedVirtualMemory

} VirtualMemoryType;

typedef struct _DataSegmentInfo

{

  void

    *allocation,

    *bound;

  MagickBooleanType

    mapped;

  size_t

    length;

  struct _DataSegmentInfo

    *previous,

    *next;

} DataSegmentInfo;

typedef struct _MagickMemoryMethods

{

  AcquireMemoryHandler

    acquire_memory_handler;

  ResizeMemoryHandler

    resize_memory_handler;

  DestroyMemoryHandler

    destroy_memory_handler;

  AcquireAlignedMemoryHandler

    acquire_aligned_memory_handler;

  RelinquishAlignedMemoryHandler

    relinquish_aligned_memory_handler;

} MagickMemoryMethods;

struct _MemoryInfo

{

  char

    filename[MagickPathExtent];

  VirtualMemoryType

    type;

  size_t

    length;

  void

    *blob;

  size_t

    signature;

};

typedef struct _MemoryPool

{

  size_t

    allocation;

  void

    *blocks[MaxBlocks+1];

  size_t

    number_segments;

  DataSegmentInfo

    *segments[MaxSegments],

    segment_pool[MaxSegments];

} MemoryPool;

/*

  Global declarations.

*/

static size_t

  max_memory_request = 0,

  max_profile_size = 0,

  virtual_anonymous_memory = 0;

static MagickMemoryMethods

  memory_methods =

  {

    (AcquireMemoryHandler) malloc,

    (ResizeMemoryHandler) realloc,

    (DestroyMemoryHandler) free,

    (AcquireAlignedMemoryHandler) NULL,

    (RelinquishAlignedMemoryHandler) NULL

  };

#if defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)

static MemoryPool

  memory_pool;

static SemaphoreInfo

  *memory_semaphore = (SemaphoreInfo *) NULL;

static volatile DataSegmentInfo

  *free_segments = (DataSegmentInfo *) NULL;

/*

  Forward declarations.

*/

static MagickBooleanType

  ExpandHeap(size_t);

#endif

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

%   A c q u i r e A l i g n e d M e m o r y                                   %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  AcquireAlignedMemory() returns a pointer to a block of memory whose size is

%  at least (count*quantum) bytes, and whose address is aligned on a cache line.

%

%  The format of the AcquireAlignedMemory method is:

%

%      void *AcquireAlignedMemory(const size_t count,const size_t quantum)

%

%  A description of each parameter follows:

%

%    o count: the number of objects to allocate contiguously.

%

%    o quantum: the size (in bytes) of each object.

%

*/

#if defined(MAGICKCORE_HAVE_ALIGNED_MALLOC)

#define AcquireAlignedMemory_Actual AcquireAlignedMemory_STDC

static inline void *AcquireAlignedMemory_STDC(const size_t size)

{

  size_t

    extent = CACHE_ALIGNED(size);

  if (extent < size)

    {

      errno=ENOMEM;

      return(NULL);

    }

  return(aligned_alloc(CACHE_LINE_SIZE,extent));

}

#elif defined(MAGICKCORE_HAVE_POSIX_MEMALIGN)

#define AcquireAlignedMemory_Actual AcquireAlignedMemory_POSIX

static inline void *AcquireAlignedMemory_POSIX(const size_t size)

{

  void

    *memory;

  if (posix_memalign(&memory,CACHE_LINE_SIZE,size))

    return(NULL);

  return(memory);

}

#elif defined(MAGICKCORE_HAVE__ALIGNED_MALLOC)

#define AcquireAlignedMemory_Actual AcquireAlignedMemory_WinAPI

static inline void *AcquireAlignedMemory_WinAPI(const size_t size)

{

  return(_aligned_malloc(size,CACHE_LINE_SIZE));

}

#else

#define ALIGNMENT_OVERHEAD \

  (MAGICKCORE_MAX_ALIGNMENT_PADDING(CACHE_LINE_SIZE) + MAGICKCORE_SIZEOF_VOID_P)

static inline void *reserve_space_for_actual_base_address(void *const p)

{

  return((void **) p+1);

}

static inline void **pointer_to_space_for_actual_base_address(void *const p)

{

  return((void **) p-1);

}

static inline void *actual_base_address(void *const p)

{

  return(*pointer_to_space_for_actual_base_address(p));

}

static inline void *align_to_cache(void *const p)

{

  return((void *) CACHE_ALIGNED((MagickAddressType) p));

}

static inline void *adjust(void *const p)

{

  return(align_to_cache(reserve_space_for_actual_base_address(p)));

}

#define AcquireAlignedMemory_Actual AcquireAlignedMemory_Generic

static inline void *AcquireAlignedMemory_Generic(const size_t size)

{

  size_t

    extent;

  void

    *memory,

    *p;

  #if SIZE_MAX < ALIGNMENT_OVERHEAD

    #error "CACHE_LINE_SIZE is way too big."

  #endif

  extent=(size+ALIGNMENT_OVERHEAD);

  if (extent <= size)

    {

      errno=ENOMEM;

      return(NULL);

    }

  p=AcquireMagickMemory(extent);

  if (p == NULL)

    return(NULL);

  memory=adjust(p);

  *pointer_to_space_for_actual_base_address(memory)=p;

  return(memory);

}

#endif

MagickExport void *AcquireAlignedMemory(const size_t count,const size_t quantum)

{

  size_t

    size;

  if (HeapOverflowSanityCheckGetSize(count,quantum,&size) != MagickFalse)

    {

      errno=ENOMEM;

      return(NULL);

    }

  if (memory_methods.acquire_aligned_memory_handler != (AcquireAlignedMemoryHandler) NULL)

    return(memory_methods.acquire_aligned_memory_handler(size,CACHE_LINE_SIZE));

  return(AcquireAlignedMemory_Actual(size));

}

#if defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

+   A c q u i r e B l o c k                                                   %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  AcquireBlock() returns a pointer to a block of memory at least size bytes

%  suitably aligned for any use.

%

%  The format of the AcquireBlock method is:

%

%      void *AcquireBlock(const size_t size)

%

%  A description of each parameter follows:

%

%    o size: the size of the memory in bytes to allocate.

%

*/

static inline size_t AllocationPolicy(size_t size)

{

  size_t

    blocksize;

  /*

    The linear distribution.

  */

  assert(size != 0);

  assert(size % (4*sizeof(size_t)) == 0);

  if (size <= BlockThreshold)

    return(size/(4*sizeof(size_t)));

  /*

    Check for the largest block size.

  */

  if (size > (size_t) (BlockThreshold*(1L << (MaxBlockExponent-1L))))

    return(MaxBlocks-1L);

  /*

    Otherwise use a power of two distribution.

  */

  blocksize=BlockThreshold/(4*sizeof(size_t));

  for ( ; size > BlockThreshold; size/=2)

    blocksize++;

  assert(blocksize > (BlockThreshold/(4*sizeof(size_t))));

  assert(blocksize < (MaxBlocks-1L));

  return(blocksize);

}

static inline void InsertFreeBlock(void *block,const size_t i)

{

  void

    *next,

    *previous;

  size_t

    size;

  size=SizeOfBlock(block);

  previous=(void *) NULL;

  next=memory_pool.blocks[i];

  while ((next != (void *) NULL) && (SizeOfBlock(next) < size))

  {

    previous=next;

    next=NextBlockInList(next);

  }

  PreviousBlockInList(block)=previous;

  NextBlockInList(block)=next;

  if (previous != (void *) NULL)

    NextBlockInList(previous)=block;

  else

    memory_pool.blocks[i]=block;

  if (next != (void *) NULL)

    PreviousBlockInList(next)=block;

}

static inline void RemoveFreeBlock(void *block,const size_t i)

{

  void

    *next,

    *previous;

  next=NextBlockInList(block);

  previous=PreviousBlockInList(block);

  if (previous == (void *) NULL)

    memory_pool.blocks[i]=next;

  else

    NextBlockInList(previous)=next;

  if (next != (void *) NULL)

    PreviousBlockInList(next)=previous;

}

static void *AcquireBlock(size_t size)

{

  size_t

    i;

  void

    *block;

  /*

    Find free block.

  */

  size=(size_t) (size+sizeof(size_t)+6*sizeof(size_t)-1) & -(4U*sizeof(size_t));

  i=AllocationPolicy(size);

  block=memory_pool.blocks[i];

  while ((block != (void *) NULL) && (SizeOfBlock(block) < size))

    block=NextBlockInList(block);

  if (block == (void *) NULL)

    {

      i++;

      while (memory_pool.blocks[i] == (void *) NULL)

        i++;

      block=memory_pool.blocks[i];

      if (i >= MaxBlocks)

        return((void *) NULL);

    }

  assert((*BlockHeader(NextBlock(block)) & PreviousBlockBit) == 0);

  assert(SizeOfBlock(block) >= size);

  RemoveFreeBlock(block,AllocationPolicy(SizeOfBlock(block)));

  if (SizeOfBlock(block) > size)

    {

      size_t

        blocksize;

      void

        *next;

      /*

        Split block.

      */

      next=(char *) block+size;

      blocksize=SizeOfBlock(block)-size;

      *BlockHeader(next)=blocksize;

      *BlockFooter(next,blocksize)=blocksize;

      InsertFreeBlock(next,AllocationPolicy(blocksize));

      *BlockHeader(block)=size | (*BlockHeader(block) & ~SizeMask);

    }

  assert(size == SizeOfBlock(block));

  *BlockHeader(NextBlock(block))|=PreviousBlockBit;

  memory_pool.allocation+=size;

  return(block);

}

#endif

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

%   A c q u i r e M a g i c k M e m o r y                                     %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  AcquireMagickMemory() returns a pointer to a block of memory at least size

%  bytes suitably aligned for any use.

%

%  The format of the AcquireMagickMemory method is:

%

%      void *AcquireMagickMemory(const size_t size)

%

%  A description of each parameter follows:

%

%    o size: the size of the memory in bytes to allocate.

%

*/

MagickExport void *AcquireMagickMemory(const size_t size)

{

  void

    *memory;

#if !defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)

  memory=memory_methods.acquire_memory_handler(size == 0 ? 1UL : size);

#else

  if (memory_semaphore == (SemaphoreInfo *) NULL)

    ActivateSemaphoreInfo(&memory_semaphore);

  if (free_segments == (DataSegmentInfo *) NULL)

    {

      LockSemaphoreInfo(memory_semaphore);

      if (free_segments == (DataSegmentInfo *) NULL)

        {

          ssize_t

            i;

          assert(2*sizeof(size_t) > (size_t) (~SizeMask));

          (void) memset(&memory_pool,0,sizeof(memory_pool));

          memory_pool.allocation=SegmentSize;

          memory_pool.blocks[MaxBlocks]=(void *) (-1);

          for (i=0; i < MaxSegments; i++)

          {

            if (i != 0)

              memory_pool.segment_pool[i].previous=

                (&memory_pool.segment_pool[i-1]);

            if (i != (MaxSegments-1))

              memory_pool.segment_pool[i].next=(&memory_pool.segment_pool[i+1]);

          }

          free_segments=(&memory_pool.segment_pool[0]);

        }

      UnlockSemaphoreInfo(memory_semaphore);

    }

  LockSemaphoreInfo(memory_semaphore);

  memory=AcquireBlock(size == 0 ? 1UL : size);

  if (memory == (void *) NULL)

    {

      if (ExpandHeap(size == 0 ? 1UL : size) != MagickFalse)

        memory=AcquireBlock(size == 0 ? 1UL : size);

    }

  UnlockSemaphoreInfo(memory_semaphore);

#endif

  return(memory);

}

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

%   A c q u i r e C r i t i c a l M e m o r y                                 %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  AcquireCriticalMemory() is just like AcquireMagickMemory(), throws a fatal

%  exception if the memory cannot be acquired.

%

%  That is, AcquireCriticalMemory() returns a pointer to a block of memory that

%  is at least size bytes, and that is suitably aligned for any use; however,

%  if this is not possible, it throws an exception and terminates the program

%  as unceremoniously as possible.

%

%  The format of the AcquireCriticalMemory method is:

%

%      void *AcquireCriticalMemory(const size_t size)

%

%  A description of each parameter follows:

%

%    o size: the size (in bytes) of the memory to allocate.

%

*/

MagickExport void *AcquireCriticalMemory(const size_t size)

{

  void

    *memory;

  /*

    Fail if memory request cannot be fulfilled.

  */

  memory=AcquireMagickMemory(size);

  if (memory == (void *) NULL)

    ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");

  return(memory);

}

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

%   A c q u i r e Q u a n t u m M e m o r y                                   %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  AcquireQuantumMemory() returns a pointer to a block of memory at least

%  count * quantum bytes suitably aligned for any use.

%

%  The format of the AcquireQuantumMemory method is:

%

%      void *AcquireQuantumMemory(const size_t count,const size_t quantum)

%

%  A description of each parameter follows:

%

%    o count: the number of objects to allocate contiguously.

%

%    o quantum: the size (in bytes) of each object.

%

*/

MagickExport void *AcquireQuantumMemory(const size_t count,const size_t quantum)

{

  size_t

    size;

  if ((HeapOverflowSanityCheckGetSize(count,quantum,&size) != MagickFalse) ||

      (size > GetMaxMemoryRequest()))

    {

      errno=ENOMEM;

      return(NULL);

    }

  return(AcquireMagickMemory(size));

}

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

%   A c q u i r e V i r t u a l M e m o r y                                   %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  AcquireVirtualMemory() allocates a pointer to a block of memory at least

%  size bytes suitably aligned for any use. In addition to heap, it also

%  supports memory-mapped and file-based memory-mapped memory requests.

%

%  The format of the AcquireVirtualMemory method is:

%

%      MemoryInfo *AcquireVirtualMemory(const size_t count,const size_t quantum)

%

%  A description of each parameter follows:

%

%    o count: the number of objects to allocate contiguously.

%

%    o quantum: the size (in bytes) of each object.

%

*/

MagickExport MemoryInfo *AcquireVirtualMemory(const size_t count,

  const size_t quantum)

{

  char

    *value;

  MemoryInfo

    *memory_info;

  size_t

    size;

  if (HeapOverflowSanityCheckGetSize(count,quantum,&size) != MagickFalse)

    {

      errno=ENOMEM;

      return((MemoryInfo *) NULL);

    }

  if (virtual_anonymous_memory == 0)

    {

      virtual_anonymous_memory=1;

      value=GetPolicyValue("system:memory-map");

      if (LocaleCompare(value,"anonymous") == 0)

        {

          /*

            The security policy sets anonymous mapping for the memory request.

          */

#if defined(MAGICKCORE_HAVE_MMAP) && defined(MAP_ANONYMOUS)

          virtual_anonymous_memory=2;

#endif

        }

      value=DestroyString(value);

    }

  memory_info=(MemoryInfo *) MagickAssumeAligned(AcquireAlignedMemory(1,

    sizeof(*memory_info)));

  if (memory_info == (MemoryInfo *) NULL)

    ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");

  (void) memset(memory_info,0,sizeof(*memory_info));

  memory_info->length=size;

  memory_info->signature=MagickCoreSignature;

  if ((virtual_anonymous_memory == 1) && (size <= GetMaxMemoryRequest()))

    {

      memory_info->blob=AcquireAlignedMemory(1,size);

      if (memory_info->blob != NULL)

        memory_info->type=AlignedVirtualMemory;

    }

  if (memory_info->blob == NULL)

    {

      /*

        Acquire anonymous memory map.

      */

      memory_info->blob=NULL;

      if (size <= GetMaxMemoryRequest())

        memory_info->blob=MapBlob(-1,IOMode,0,size);

      if (memory_info->blob != NULL)

        memory_info->type=MapVirtualMemory;

      else

        {

          int

            file;

          /*

            Anonymous memory mapping failed, try file-backed memory mapping.

          */

          file=AcquireUniqueFileResource(memory_info->filename);

          if (file != -1)

            {

              MagickOffsetType

                offset;

              offset=(MagickOffsetType) lseek(file,(off_t) (size-1),SEEK_SET);

              if ((offset == (MagickOffsetType) (size-1)) &&

                  (write(file,"",1) == 1))

                {

#if !defined(MAGICKCORE_HAVE_POSIX_FALLOCATE)

                  memory_info->blob=MapBlob(file,IOMode,0,size);

#else

                  if (posix_fallocate(file,0,(MagickOffsetType) size) == 0)

                    memory_info->blob=MapBlob(file,IOMode,0,size);

#endif

                  if (memory_info->blob != NULL)

                    memory_info->type=MapVirtualMemory;

                  else

                    {

                      (void) RelinquishUniqueFileResource(

                        memory_info->filename);

                      *memory_info->filename='\0';

                    }

                }

              (void) close_utf8(file);

            }

        }

    }

  if (memory_info->blob == NULL)

    {

      memory_info->blob=AcquireQuantumMemory(1,size);

      if (memory_info->blob != NULL)

        memory_info->type=UnalignedVirtualMemory;

    }

  if (memory_info->blob == NULL)

    memory_info=RelinquishVirtualMemory(memory_info);

  return(memory_info);

}

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

%   C o p y M a g i c k M e m o r y                                           %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  CopyMagickMemory() copies size bytes from memory area source to the

%  destination.  Copying between objects that overlap will take place

%  correctly.  It returns destination.

%

%  The format of the CopyMagickMemory method is:

%

%      void *CopyMagickMemory(void *magick_restrict destination,

%        const void *magick_restrict source,const size_t size)

%

%  A description of each parameter follows:

%

%    o destination: the destination.

%

%    o source: the source.

%

%    o size: the size of the memory in bytes to allocate.

%

*/

MagickExport void *CopyMagickMemory(void *magick_restrict destination,

  const void *magick_restrict source,const size_t size)

{

  const unsigned char

    *p;

  unsigned char

    *q;

  assert(destination != (void *) NULL);

  assert(source != (const void *) NULL);

  p=(const unsigned char *) source;

  q=(unsigned char *) destination;

  if (((q+size) < p) || (q > (p+size)))

    switch (size)

    {

      default: return(memcpy(destination,source,size));

      case 8: *q++=(*p++); magick_fallthrough;

      case 7: *q++=(*p++); magick_fallthrough;

      case 6: *q++=(*p++); magick_fallthrough;

      case 5: *q++=(*p++); magick_fallthrough;

      case 4: *q++=(*p++); magick_fallthrough;

      case 3: *q++=(*p++); magick_fallthrough;

      case 2: *q++=(*p++); magick_fallthrough;

      case 1: *q++=(*p++); magick_fallthrough;

      case 0: return(destination);

    }

  return(memmove(destination,source,size));

}

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

+   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_ANONYMOUS_MEMORY_SUPPORT)

  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) memset(&memory_pool,0,sizeof(memory_pool));

  UnlockSemaphoreInfo(memory_semaphore);

  RelinquishSemaphoreInfo(&memory_semaphore);

#endif

}

#if defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

+   E x p a n d H e a p                                                       %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  ExpandHeap() get more memory from the system.  It returns MagickTrue on

%  success otherwise MagickFalse.

%

%  The format of the ExpandHeap method is:

%

%      MagickBooleanType ExpandHeap(size_t size)

%

%  A description of each parameter follows:

%

%    o size: the size of the memory in bytes we require.

%

*/

static MagickBooleanType ExpandHeap(size_t size)

{

  DataSegmentInfo

    *segment_info;

  MagickBooleanType

    mapped;

  ssize_t

    i;

  void

    *block;

  size_t

    blocksize;

  void

    *segment;

  blocksize=((size+12*sizeof(size_t))+SegmentSize-1) & -SegmentSize;

  assert(memory_pool.number_segments < MaxSegments);

  segment=MapBlob(-1,IOMode,0,blocksize);

  mapped=segment != (void *) NULL ? MagickTrue : MagickFalse;

  if (segment == (void *) NULL)

    segment=(void *) memory_methods.acquire_memory_handler(blocksize);

  if (segment == (void *) NULL)

    return(MagickFalse);

  segment_info=(DataSegmentInfo *) free_segments;

  free_segments=segment_info->next;

  segment_info->mapped=mapped;

  segment_info->length=blocksize;

  segment_info->allocation=segment;

  segment_info->bound=(char *) segment+blocksize;

  i=(ssize_t) memory_pool.number_segments-1;

  for ( ; (i >= 0) && (memory_pool.segments[i]->allocation > segment); i--)

    memory_pool.segments[i+1]=memory_pool.segments[i];

  memory_pool.segments[i+1]=segment_info;

  memory_pool.number_segments++;

  size=blocksize-12*sizeof(size_t);

  block=(char *) segment_info->allocation+4*sizeof(size_t);

  *BlockHeader(block)=size | PreviousBlockBit;

  *BlockFooter(block,size)=size;

  InsertFreeBlock(block,AllocationPolicy(size));

  block=NextBlock(block);

  assert(block < segment_info->bound);

  *BlockHeader(block)=2*sizeof(size_t);

  *BlockHeader(NextBlock(block))=PreviousBlockBit;

  return(MagickTrue);

}

#endif

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

%   G e t M a g i c k M e m o r y M e t h o d s                               %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  GetMagickMemoryMethods() gets the methods to acquire, resize, and destroy

%  memory.

%

%  The format of the GetMagickMemoryMethods() method is:

%

%      void GetMagickMemoryMethods(AcquireMemoryHandler *acquire_memory_handler,

%        ResizeMemoryHandler *resize_memory_handler,

%        DestroyMemoryHandler *destroy_memory_handler)

%

%  A description of each parameter follows:

%

%    o acquire_memory_handler: method to acquire memory (e.g. malloc).

%

%    o resize_memory_handler: method to resize memory (e.g. realloc).

%

%    o destroy_memory_handler: method to destroy memory (e.g. free).

%

*/

MagickExport void GetMagickMemoryMethods(

  AcquireMemoryHandler *acquire_memory_handler,

  ResizeMemoryHandler *resize_memory_handler,

  DestroyMemoryHandler *destroy_memory_handler)

{

  assert(acquire_memory_handler != (AcquireMemoryHandler *) NULL);

  assert(resize_memory_handler != (ResizeMemoryHandler *) NULL);

  assert(destroy_memory_handler != (DestroyMemoryHandler *) NULL);

  *acquire_memory_handler=memory_methods.acquire_memory_handler;

  *resize_memory_handler=memory_methods.resize_memory_handler;

  *destroy_memory_handler=memory_methods.destroy_memory_handler;

}

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

+   G e t M a x M e m o r y R e q u e s t                                     %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  GetMaxMemoryRequest() returns the max memory request value.

%

%  The format of the GetMaxMemoryRequest method is:

%

%      size_t GetMaxMemoryRequest(void)

%

*/

static size_t GetMaxMemoryRequestFromPolicy(void)

{

#define MinMemoryRequest "16MiB"

  char

    *value;

  size_t

    max_memory = (size_t) MAGICK_SSIZE_MAX;

  value=GetPolicyValue("system:max-memory-request");

  if (value != (char *) NULL)

    {

      /*

        The security policy sets a max memory request limit.

      */

      max_memory=MagickMax(StringToSizeType(value,100.0),StringToSizeType(

        MinMemoryRequest,100.0));

      value=DestroyString(value);

    }

  return(MagickMin(max_memory,(size_t) MAGICK_SSIZE_MAX));

}

MagickExport size_t GetMaxMemoryRequest(void)

{

  if (max_memory_request == 0)

    {

      /*

        Setting this to unlimited before we check the policy value to avoid

        recursive calls to GetMaxMemoryRequestFromPolicy()

      */

      max_memory_request=(size_t) MAGICK_SSIZE_MAX;

      max_memory_request=GetMaxMemoryRequestFromPolicy();

    } 

  return(max_memory_request);

}

/*

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

%                                                                             %

%                                                                             %

%                                                                             %

+   G e t M a x P r o f i l e S i z e                                         %

%                                                                             %

%                                                                             %

%                                                                             %

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

%

%  GetMaxProfileSize() returns the max profile size value.

%

%  The format of the GetMaxMemoryRequest method is:

%

%      size_t GetMaxProfileSize(void)

%

*/

static size_t GetMaxProfileSizeFromPolicy(void)

{

  char

    *value;

  size_t

    max=(size_t) MAGICK_SSIZE_MAX;

  value=GetPolicyValue("system:max-profile-size");

  if (value != (char *) NULL)

    {

      /*

        The security policy sets a max profile size limit.

      */

      max=StringToSizeType(value,100.0);

      value=DestroyString(value);

    }

  return(MagickMin(max,(size_t) MAGICK_SSIZE_MAX));

}

MagickExport size_t GetMaxProfileSize(void)

{

  if (max_profile_size == 0)

    max_profile_size=GetMaxProfileSizeFromPolicy();

  return(max_profile_size);

}