imagemagick/magick/memory.c

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/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% 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 1999-2021 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/script/license.php %
% %
% 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 "magick/studio.h"
#include "magick/blob.h"
#include "magick/blob-private.h"
#include "magick/exception.h"
#include "magick/exception-private.h"
#include "magick/image-private.h"
#include "magick/memory_.h"
#include "magick/memory-private.h"
#include "magick/policy.h"
#include "magick/resource_.h"
#include "magick/semaphore.h"
#include "magick/string_.h"
#include "magick/string-private.h"
#include "magick/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,
virtual_anonymous_memory = 0;
#if defined _MSC_VER
static void *MSCMalloc(size_t size)
{
return(malloc(size));
}
static void *MSCRealloc(void* ptr, size_t size)
{
return(realloc(ptr,size));
}
static void MSCFree(void* ptr)
{
free(ptr);
}
#endif
static MagickMemoryMethods
memory_methods =
{
#if defined _MSC_VER
(AcquireMemoryHandler) MSCMalloc,
(ResizeMemoryHandler) MSCRealloc,
(DestroyMemoryHandler) MSCFree,
#else
(AcquireMemoryHandler) malloc,
(ResizeMemoryHandler) realloc,
(DestroyMemoryHandler) free,
#endif
(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,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(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++);
case 7: *q++=(*p++);
case 6: *q++=(*p++);
case 5: *q++=(*p++);
case 4: *q++=(*p++);
case 3: *q++=(*p++);
case 2: *q++=(*p++);
case 1: *q++=(*p++);
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);
DestroySemaphoreInfo(&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)
%
*/
MagickExport size_t GetMaxMemoryRequest(void)
{
#define MinMemoryRequest "16MiB"
if (max_memory_request == 0)
{
char
*value;
max_memory_request=(size_t) MagickULLConstant(~0);
value=GetPolicyValue("system:max-memory-request");
if (value != (char *) NULL)
{
/*
The security policy sets a max memory request limit.
*/
max_memory_request=MagickMax(StringToSizeType(value,100.0),
StringToSizeType(MinMemoryRequest,100.0));
value=DestroyString(value);
}
}
return(MagickMin(max_memory_request,MAGICK_SSIZE_MAX));
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% G e t V i r t u a l M e m o r y B l o b %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% GetVirtualMemoryBlob() returns the virtual memory blob associated with the
% specified MemoryInfo structure.
%
% The format of the GetVirtualMemoryBlob method is:
%
% void *GetVirtualMemoryBlob(const MemoryInfo *memory_info)
%
% A description of each parameter follows:
%
% o memory_info: The MemoryInfo structure.
*/
MagickExport void *GetVirtualMemoryBlob(const MemoryInfo *memory_info)
{
assert(memory_info != (const MemoryInfo *) NULL);
assert(memory_info->signature == MagickCoreSignature);
return(memory_info->blob);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e l i n q u i s h A l i g n e d M e m o r y %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% RelinquishAlignedMemory() frees memory acquired with AcquireAlignedMemory()
% or reuse.
%
% The format of the RelinquishAlignedMemory method is:
%
% void *RelinquishAlignedMemory(void *memory)
%
% A description of each parameter follows:
%
% o memory: A pointer to a block of memory to free for reuse.
%
*/
MagickExport void *RelinquishAlignedMemory(void *memory)
{
if (memory == (void *) NULL)
return((void *) NULL);
if (memory_methods.relinquish_aligned_memory_handler != (RelinquishAlignedMemoryHandler) NULL)
{
memory_methods.relinquish_aligned_memory_handler(memory);
return(NULL);
}
#if defined(MAGICKCORE_HAVE_ALIGNED_MALLOC) || defined(MAGICKCORE_HAVE_POSIX_MEMALIGN)
free(memory);
#elif defined(MAGICKCORE_HAVE__ALIGNED_MALLOC)
_aligned_free(memory);
#else
RelinquishMagickMemory(actual_base_address(memory));
#endif
return(NULL);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e l i n q u i s h M a g i c k M e m o r y %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% RelinquishMagickMemory() frees memory acquired with AcquireMagickMemory()
% or AcquireQuantumMemory() for reuse.
%
% The format of the RelinquishMagickMemory method is:
%
% void *RelinquishMagickMemory(void *memory)
%
% A description of each parameter follows:
%
% o memory: A pointer to a block of memory to free for reuse.
%
*/
MagickExport void *RelinquishMagickMemory(void *memory)
{
if (memory == (void *) NULL)
return((void *) NULL);
#if !defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
memory_methods.destroy_memory_handler(memory);
#else
LockSemaphoreInfo(memory_semaphore);
assert((SizeOfBlock(memory) % (4*sizeof(size_t))) == 0);
assert((*BlockHeader(NextBlock(memory)) & PreviousBlockBit) != 0);
if ((*BlockHeader(memory) & PreviousBlockBit) == 0)
{
void
*previous;
/*
Coalesce with previous adjacent block.
*/
previous=PreviousBlock(memory);
RemoveFreeBlock(previous,AllocationPolicy(SizeOfBlock(previous)));
*BlockHeader(previous)=(SizeOfBlock(previous)+SizeOfBlock(memory)) |
(*BlockHeader(previous) & ~SizeMask);
memory=previous;
}
if ((*BlockHeader(NextBlock(NextBlock(memory))) & PreviousBlockBit) == 0)
{
void
*next;
/*
Coalesce with next adjacent block.
*/
next=NextBlock(memory);
RemoveFreeBlock(next,AllocationPolicy(SizeOfBlock(next)));
*BlockHeader(memory)=(SizeOfBlock(memory)+SizeOfBlock(next)) |
(*BlockHeader(memory) & ~SizeMask);
}
*BlockFooter(memory,SizeOfBlock(memory))=SizeOfBlock(memory);
*BlockHeader(NextBlock(memory))&=(~PreviousBlockBit);
InsertFreeBlock(memory,AllocationPolicy(SizeOfBlock(memory)));
UnlockSemaphoreInfo(memory_semaphore);
#endif
return((void *) NULL);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e l i n q u i s h V i r t u a l M e m o r y %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% RelinquishVirtualMemory() frees memory acquired with AcquireVirtualMemory().
%
% The format of the RelinquishVirtualMemory method is:
%
% MemoryInfo *RelinquishVirtualMemory(MemoryInfo *memory_info)
%
% A description of each parameter follows:
%
% o memory_info: A pointer to a block of memory to free for reuse.
%
*/
MagickExport MemoryInfo *RelinquishVirtualMemory(MemoryInfo *memory_info)
{
assert(memory_info != (MemoryInfo *) NULL);
assert(memory_info->signature == MagickCoreSignature);
if (memory_info->blob != (void *) NULL)
switch (memory_info->type)
{
case AlignedVirtualMemory:
{
memory_info->blob=RelinquishAlignedMemory(memory_info->blob);
break;
}
case MapVirtualMemory:
{
(void) UnmapBlob(memory_info->blob,memory_info->length);
memory_info->blob=NULL;
if (*memory_info->filename != '\0')
(void) RelinquishUniqueFileResource(memory_info->filename);
break;
}
case UnalignedVirtualMemory:
default:
{
memory_info->blob=RelinquishMagickMemory(memory_info->blob);
break;
}
}
memory_info->signature=(~MagickCoreSignature);
memory_info=(MemoryInfo *) RelinquishAlignedMemory(memory_info);
return(memory_info);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e s e t M a g i c k M e m o r y %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ResetMagickMemory() fills the first size bytes of the memory area pointed to
% by memory with the constant byte c.
%
% The format of the ResetMagickMemory method is:
%
% void *ResetMagickMemory(void *memory,int byte,const size_t size)
%
% A description of each parameter follows:
%
% o memory: a pointer to a memory allocation.
%
% o byte: set the memory to this value.
%
% o size: size of the memory to reset.
%
*/
MagickExport void *ResetMagickMemory(void *memory,int byte,const size_t size)
{
assert(memory != (void *) NULL);
return(memset(memory,byte,size));
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
+ R e s e t M a x M e m o r y R e q u e s t %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ResetMaxMemoryRequest() resets the max_memory_request value.
%
% The format of the ResetMaxMemoryRequest method is:
%
% void ResetMaxMemoryRequest(void)
%
*/
MagickPrivate void ResetMaxMemoryRequest(void)
{
max_memory_request=0;
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
+ R e s e t V i r t u a l A n o n y m o u s M e m o r y %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ResetVirtualAnonymousMemory() resets the virtual_anonymous_memory value.
%
% The format of the ResetVirtualAnonymousMemory method is:
%
% void ResetVirtualAnonymousMemory(void)
%
*/
MagickPrivate void ResetVirtualAnonymousMemory(void)
{
virtual_anonymous_memory=0;
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e s i z e M a g i c k M e m o r y %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ResizeMagickMemory() changes the size of the memory and returns a pointer to
% the (possibly moved) block. The contents will be unchanged up to the
% lesser of the new and old sizes.
%
% The format of the ResizeMagickMemory method is:
%
% void *ResizeMagickMemory(void *memory,const size_t size)
%
% A description of each parameter follows:
%
% o memory: A pointer to a memory allocation.
%
% o size: the new size of the allocated memory.
%
*/
#if defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
static inline void *ResizeBlock(void *block,size_t size)
{
void
*memory;
if (block == (void *) NULL)
return(AcquireBlock(size));
memory=AcquireBlock(size);
if (memory == (void *) NULL)
return((void *) NULL);
if (size <= (SizeOfBlock(block)-sizeof(size_t)))
(void) memcpy(memory,block,size);
else
(void) memcpy(memory,block,SizeOfBlock(block)-sizeof(size_t));
memory_pool.allocation+=size;
return(memory);
}
#endif
MagickExport void *ResizeMagickMemory(void *memory,const size_t size)
{
void
*block;
if (memory == (void *) NULL)
return(AcquireMagickMemory(size));
#if !defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
block=memory_methods.resize_memory_handler(memory,size == 0 ? 1UL : size);
if (block == (void *) NULL)
memory=RelinquishMagickMemory(memory);
#else
LockSemaphoreInfo(memory_semaphore);
block=ResizeBlock(memory,size == 0 ? 1UL : size);
if (block == (void *) NULL)
{
if (ExpandHeap(size == 0 ? 1UL : size) == MagickFalse)
{
UnlockSemaphoreInfo(memory_semaphore);
memory=RelinquishMagickMemory(memory);
ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
}
block=ResizeBlock(memory,size == 0 ? 1UL : size);
assert(block != (void *) NULL);
}
UnlockSemaphoreInfo(memory_semaphore);
memory=RelinquishMagickMemory(memory);
#endif
return(block);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e s i z e Q u a n t u m M e m o r y %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ResizeQuantumMemory() changes the size of the memory and returns a pointer
% to the (possibly moved) block. The contents will be unchanged up to the
% lesser of the new and old sizes.
%
% The format of the ResizeQuantumMemory method is:
%
% void *ResizeQuantumMemory(void *memory,const size_t count,
% const size_t quantum)
%
% A description of each parameter follows:
%
% o memory: A pointer to a memory allocation.
%
% o count: the number of objects to allocate contiguously.
%
% o quantum: the size (in bytes) of each object.
%
*/
MagickExport void *ResizeQuantumMemory(void *memory,const size_t count,
const size_t quantum)
{
size_t
size;
if ((HeapOverflowSanityCheckGetSize(count,quantum,&size) != MagickFalse) ||
(size > GetMaxMemoryRequest()))
{
errno=ENOMEM;
memory=RelinquishMagickMemory(memory);
return(NULL);
}
if (size > GetMaxMemoryRequest())
return(NULL);
return(ResizeMagickMemory(memory,size));
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% S e t M a g i c k A l i g n e d M e m o r y M e t h o d s %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% SetMagickAlignedMemoryMethods() sets the methods to acquire and relinquish
% aligned memory.
%
% The format of the SetMagickAlignedMemoryMethods() method is:
%
% SetMagickAlignedMemoryMethods(
% AcquireAlignedMemoryHandler acquire_aligned_memory_handler,
% RelinquishAlignedMemoryHandler relinquish_aligned_memory_handler)
%
% A description of each parameter follows:
%
% o acquire_memory_handler: method to acquire aligned memory.
%
% o relinquish_aligned_memory_handler: method to relinquish aligned memory.
%
*/
MagickExport void SetMagickAlignedMemoryMethods(
AcquireAlignedMemoryHandler acquire_aligned_memory_handler,
RelinquishAlignedMemoryHandler relinquish_aligned_memory_handler)
{
memory_methods.acquire_aligned_memory_handler=acquire_aligned_memory_handler;
memory_methods.relinquish_aligned_memory_handler=
relinquish_aligned_memory_handler;
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% S e t M a g i c k M e m o r y M e t h o d s %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% SetMagickMemoryMethods() sets the methods to acquire, resize, and destroy
% memory. Your custom memory methods must be set prior to the
% MagickCoreGenesis() method.
%
% The format of the SetMagickMemoryMethods() method is:
%
% SetMagickMemoryMethods(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 SetMagickMemoryMethods(
AcquireMemoryHandler acquire_memory_handler,
ResizeMemoryHandler resize_memory_handler,
DestroyMemoryHandler destroy_memory_handler)
{
/*
Set memory methods.
*/
if (acquire_memory_handler != (AcquireMemoryHandler) NULL)
memory_methods.acquire_memory_handler=acquire_memory_handler;
if (resize_memory_handler != (ResizeMemoryHandler) NULL)
memory_methods.resize_memory_handler=resize_memory_handler;
if (destroy_memory_handler != (DestroyMemoryHandler) NULL)
memory_methods.destroy_memory_handler=destroy_memory_handler;
}