MagickCore 6.9.13
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memory.c
1/*
2%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3% %
4% %
5% %
6% M M EEEEE M M OOO RRRR Y Y %
7% MM MM E MM MM O O R R Y Y %
8% M M M EEE M M M O O RRRR Y %
9% M M E M M O O R R Y %
10% M M EEEEE M M OOO R R Y %
11% %
12% %
13% MagickCore Memory Allocation Methods %
14% %
15% Software Design %
16% Cristy %
17% July 1998 %
18% %
19% %
20% Copyright 1999 ImageMagick Studio LLC, a non-profit organization %
21% dedicated to making software imaging solutions freely available. %
22% %
23% You may not use this file except in compliance with the License. You may %
24% obtain a copy of the License at %
25% %
26% https://imagemagick.org/script/license.php %
27% %
28% Unless required by applicable law or agreed to in writing, software %
29% distributed under the License is distributed on an "AS IS" BASIS, %
30% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %
31% See the License for the specific language governing permissions and %
32% limitations under the License. %
33% %
34%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
35%
36% We provide these memory allocators:
37%
38% AcquireCriticalMemory(): allocate a small memory request with
39% AcquireMagickMemory(), however, on fail throw a fatal exception and exit.
40% Free the memory reserve with RelinquishMagickMemory().
41% AcquireAlignedMemory(): allocate a small memory request that is aligned
42% on a cache line. On fail, return NULL for possible recovery.
43% Free the memory reserve with RelinquishMagickMemory().
44% AcquireMagickMemory()/ResizeMagickMemory(): allocate a small to medium
45% memory request, typically with malloc()/realloc(). On fail, return NULL
46% for possible recovery. Free the memory reserve with
47% RelinquishMagickMemory().
48% AcquireQuantumMemory()/ResizeQuantumMemory(): allocate a small to medium
49% memory request. This is a secure memory allocator as it accepts two
50% parameters, count and quantum, to ensure the request does not overflow.
51% It also check to ensure the request does not exceed the maximum memory
52% per the security policy. Free the memory reserve with
53% RelinquishMagickMemory().
54% AcquireVirtualMemory(): allocate a large memory request either in heap,
55% memory-mapped, or memory-mapped on disk depending on whether heap
56% allocation fails or if the request exceeds the maximum memory policy.
57% Free the memory reserve with RelinquishVirtualMemory().
58% ResetMagickMemory(): fills the bytes of the memory area with a constant
59% byte.
60%
61% In addition, we provide hooks for your own memory constructor/destructors.
62% You can also utilize our internal custom allocator as follows: Segregate
63% our memory requirements from any program that calls our API. This should
64% help reduce the risk of others changing our program state or causing memory
65% corruption.
66%
67% Our custom memory allocation manager implements a best-fit allocation policy
68% using segregated free lists. It uses a linear distribution of size classes
69% for lower sizes and a power of two distribution of size classes at higher
70% sizes. It is based on the paper, "Fast Memory Allocation using Lazy Fits."
71% written by Yoo C. Chung.
72%
73% By default, C's standard library is used (e.g. malloc); use the
74% custom memory allocator by defining MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT
75% to allocate memory with private anonymous mapping rather than from the
76% heap.
77%
78*/
79␌
80/*
81 Include declarations.
82*/
83#include "magick/studio.h"
84#include "magick/blob.h"
85#include "magick/blob-private.h"
86#include "magick/exception.h"
87#include "magick/exception-private.h"
88#include "magick/image-private.h"
89#include "magick/memory_.h"
90#include "magick/memory-private.h"
91#include "magick/policy.h"
92#include "magick/random_.h"
93#include "magick/resource_.h"
94#include "magick/semaphore.h"
95#include "magick/string_.h"
96#include "magick/string-private.h"
97#include "magick/utility-private.h"
98␌
99/*
100 Define declarations.
101*/
102#define BlockFooter(block,size) \
103 ((size_t *) ((char *) (block)+(size)-2*sizeof(size_t)))
104#define BlockHeader(block) ((size_t *) (block)-1)
105#define BlockThreshold 1024
106#define MaxBlockExponent 16
107#define MaxBlocks ((BlockThreshold/(4*sizeof(size_t)))+MaxBlockExponent+1)
108#define MaxSegments 1024
109#define NextBlock(block) ((char *) (block)+SizeOfBlock(block))
110#define NextBlockInList(block) (*(void **) (block))
111#define PreviousBlock(block) ((char *) (block)-(*((size_t *) (block)-2)))
112#define PreviousBlockBit 0x01
113#define PreviousBlockInList(block) (*((void **) (block)+1))
114#define SegmentSize (2*1024*1024)
115#define SizeMask (~0x01)
116#define SizeOfBlock(block) (*BlockHeader(block) & SizeMask)
117␌
118/*
119 Typedef declarations.
120*/
121typedef enum
122{
123 UndefinedVirtualMemory,
124 AlignedVirtualMemory,
125 MapVirtualMemory,
126 UnalignedVirtualMemory
127} VirtualMemoryType;
128
129typedef struct _DataSegmentInfo
130{
131 void
132 *allocation,
133 *bound;
134
135 MagickBooleanType
136 mapped;
137
138 size_t
139 length;
140
141 struct _DataSegmentInfo
142 *previous,
143 *next;
144} DataSegmentInfo;
145
146typedef struct _MagickMemoryMethods
147{
148 AcquireMemoryHandler
149 acquire_memory_handler;
150
151 ResizeMemoryHandler
152 resize_memory_handler;
153
154 DestroyMemoryHandler
155 destroy_memory_handler;
156
157 AcquireAlignedMemoryHandler
158 acquire_aligned_memory_handler;
159
160 RelinquishAlignedMemoryHandler
161 relinquish_aligned_memory_handler;
162} MagickMemoryMethods;
163
164struct _MemoryInfo
165{
166 char
167 filename[MagickPathExtent];
168
169 VirtualMemoryType
170 type;
171
172 size_t
173 length;
174
175 void
176 *blob;
177
178 size_t
179 signature;
180};
181
182typedef struct _MemoryPool
183{
184 size_t
185 allocation;
186
187 void
188 *blocks[MaxBlocks+1];
189
190 size_t
191 number_segments;
192
193 DataSegmentInfo
194 *segments[MaxSegments],
195 segment_pool[MaxSegments];
196} MemoryPool;
197␌
198/*
199 Global declarations.
200*/
201static size_t
202 max_memory_request = 0,
203 virtual_anonymous_memory = 0;
204
205#if defined _MSC_VER
206static void *MSCMalloc(size_t size)
207{
208 return(malloc(size));
209}
210
211static void *MSCRealloc(void* ptr, size_t size)
212{
213 return(realloc(ptr,size));
214}
215
216static void MSCFree(void* ptr)
217{
218 free(ptr);
219}
220#endif
221
222static MagickMemoryMethods
223 memory_methods =
224 {
225#if defined _MSC_VER
226 (AcquireMemoryHandler) MSCMalloc,
227 (ResizeMemoryHandler) MSCRealloc,
228 (DestroyMemoryHandler) MSCFree,
229#else
230 (AcquireMemoryHandler) malloc,
231 (ResizeMemoryHandler) realloc,
232 (DestroyMemoryHandler) free,
233#endif
234 (AcquireAlignedMemoryHandler) NULL,
235 (RelinquishAlignedMemoryHandler) NULL
236 };
237#if defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
238static MemoryPool
239 memory_pool;
240
241static SemaphoreInfo
242 *memory_semaphore = (SemaphoreInfo *) NULL;
243
244static volatile DataSegmentInfo
245 *free_segments = (DataSegmentInfo *) NULL;
246␌
247/*
248 Forward declarations.
249*/
250static MagickBooleanType
251 ExpandHeap(size_t);
252#endif
253␌
254/*
255%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
256% %
257% %
258% %
259% A c q u i r e A l i g n e d M e m o r y %
260% %
261% %
262% %
263%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
264%
265% AcquireAlignedMemory() returns a pointer to a block of memory whose size is
266% at least (count*quantum) bytes, and whose address is aligned on a cache line.
267%
268% The format of the AcquireAlignedMemory method is:
269%
270% void *AcquireAlignedMemory(const size_t count,const size_t quantum)
271%
272% A description of each parameter follows:
273%
274% o count: the number of objects to allocate contiguously.
275%
276% o quantum: the size (in bytes) of each object.
277%
278*/
279#if defined(MAGICKCORE_HAVE_ALIGNED_MALLOC)
280#define AcquireAlignedMemory_Actual AcquireAlignedMemory_STDC
281static inline void *AcquireAlignedMemory_STDC(const size_t size)
282{
283 size_t
284 extent = CACHE_ALIGNED(size);
285
286 if (extent < size)
287 {
288 errno=ENOMEM;
289 return(NULL);
290 }
291 return(aligned_alloc(CACHE_LINE_SIZE,extent));
292}
293#elif defined(MAGICKCORE_HAVE_POSIX_MEMALIGN)
294#define AcquireAlignedMemory_Actual AcquireAlignedMemory_POSIX
295static inline void *AcquireAlignedMemory_POSIX(const size_t size)
296{
297 void
298 *memory;
299
300 if (posix_memalign(&memory,CACHE_LINE_SIZE,size))
301 return(NULL);
302 return(memory);
303}
304#elif defined(MAGICKCORE_HAVE__ALIGNED_MALLOC)
305#define AcquireAlignedMemory_Actual AcquireAlignedMemory_WinAPI
306static inline void *AcquireAlignedMemory_WinAPI(const size_t size)
307{
308 return(_aligned_malloc(size,CACHE_LINE_SIZE));
309}
310#else
311#define ALIGNMENT_OVERHEAD \
312 (MAGICKCORE_MAX_ALIGNMENT_PADDING(CACHE_LINE_SIZE) + MAGICKCORE_SIZEOF_VOID_P)
313static inline void *reserve_space_for_actual_base_address(void *const p)
314{
315 return((void **) p+1);
316}
317
318static inline void **pointer_to_space_for_actual_base_address(void *const p)
319{
320 return((void **) p-1);
321}
322
323static inline void *actual_base_address(void *const p)
324{
325 return(*pointer_to_space_for_actual_base_address(p));
326}
327
328static inline void *align_to_cache(void *const p)
329{
330 return((void *) CACHE_ALIGNED((MagickAddressType) p));
331}
332
333static inline void *adjust(void *const p)
334{
335 return(align_to_cache(reserve_space_for_actual_base_address(p)));
336}
337
338#define AcquireAlignedMemory_Actual AcquireAlignedMemory_Generic
339static inline void *AcquireAlignedMemory_Generic(const size_t size)
340{
341 size_t
342 extent;
343
344 void
345 *memory,
346 *p;
347
348 #if SIZE_MAX < ALIGNMENT_OVERHEAD
349 #error "CACHE_LINE_SIZE is way too big."
350 #endif
351 extent=(size+ALIGNMENT_OVERHEAD);
352 if (extent <= size)
353 {
354 errno=ENOMEM;
355 return(NULL);
356 }
357 p=AcquireMagickMemory(extent);
358 if (p == NULL)
359 return(NULL);
360 memory=adjust(p);
361 *pointer_to_space_for_actual_base_address(memory)=p;
362 return(memory);
363}
364#endif
365
366MagickExport void *AcquireAlignedMemory(const size_t count,const size_t quantum)
367{
368 size_t
369 size;
370
371 if (HeapOverflowSanityCheckGetSize(count,quantum,&size) != MagickFalse)
372 {
373 errno=ENOMEM;
374 return(NULL);
375 }
376 if (memory_methods.acquire_aligned_memory_handler != (AcquireAlignedMemoryHandler) NULL)
377 return(memory_methods.acquire_aligned_memory_handler(size,CACHE_LINE_SIZE));
378 return(AcquireAlignedMemory_Actual(size));
379}
380␌
381#if defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
382/*
383%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
384% %
385% %
386% %
387+ A c q u i r e B l o c k %
388% %
389% %
390% %
391%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
392%
393% AcquireBlock() returns a pointer to a block of memory at least size bytes
394% suitably aligned for any use.
395%
396% The format of the AcquireBlock method is:
397%
398% void *AcquireBlock(const size_t size)
399%
400% A description of each parameter follows:
401%
402% o size: the size of the memory in bytes to allocate.
403%
404*/
405
406static inline size_t AllocationPolicy(size_t size)
407{
408 size_t
409 blocksize;
410
411 /*
412 The linear distribution.
413 */
414 assert(size != 0);
415 assert(size % (4*sizeof(size_t)) == 0);
416 if (size <= BlockThreshold)
417 return(size/(4*sizeof(size_t)));
418 /*
419 Check for the largest block size.
420 */
421 if (size > (size_t) (BlockThreshold*(1L << (MaxBlockExponent-1L))))
422 return(MaxBlocks-1L);
423 /*
424 Otherwise use a power of two distribution.
425 */
426 blocksize=BlockThreshold/(4*sizeof(size_t));
427 for ( ; size > BlockThreshold; size/=2)
428 blocksize++;
429 assert(blocksize > (BlockThreshold/(4*sizeof(size_t))));
430 assert(blocksize < (MaxBlocks-1L));
431 return(blocksize);
432}
433
434static inline void InsertFreeBlock(void *block,const size_t i)
435{
436 void
437 *next,
438 *previous;
439
440 size_t
441 size;
442
443 size=SizeOfBlock(block);
444 previous=(void *) NULL;
445 next=memory_pool.blocks[i];
446 while ((next != (void *) NULL) && (SizeOfBlock(next) < size))
447 {
448 previous=next;
449 next=NextBlockInList(next);
450 }
451 PreviousBlockInList(block)=previous;
452 NextBlockInList(block)=next;
453 if (previous != (void *) NULL)
454 NextBlockInList(previous)=block;
455 else
456 memory_pool.blocks[i]=block;
457 if (next != (void *) NULL)
458 PreviousBlockInList(next)=block;
459}
460
461static inline void RemoveFreeBlock(void *block,const size_t i)
462{
463 void
464 *next,
465 *previous;
466
467 next=NextBlockInList(block);
468 previous=PreviousBlockInList(block);
469 if (previous == (void *) NULL)
470 memory_pool.blocks[i]=next;
471 else
472 NextBlockInList(previous)=next;
473 if (next != (void *) NULL)
474 PreviousBlockInList(next)=previous;
475}
476
477static void *AcquireBlock(size_t size)
478{
479 size_t
480 i;
481
482 void
483 *block;
484
485 /*
486 Find free block.
487 */
488 size=(size_t) (size+sizeof(size_t)+6*sizeof(size_t)-1) & -(4U*sizeof(size_t));
489 i=AllocationPolicy(size);
490 block=memory_pool.blocks[i];
491 while ((block != (void *) NULL) && (SizeOfBlock(block) < size))
492 block=NextBlockInList(block);
493 if (block == (void *) NULL)
494 {
495 i++;
496 while (memory_pool.blocks[i] == (void *) NULL)
497 i++;
498 block=memory_pool.blocks[i];
499 if (i >= MaxBlocks)
500 return((void *) NULL);
501 }
502 assert((*BlockHeader(NextBlock(block)) & PreviousBlockBit) == 0);
503 assert(SizeOfBlock(block) >= size);
504 RemoveFreeBlock(block,AllocationPolicy(SizeOfBlock(block)));
505 if (SizeOfBlock(block) > size)
506 {
507 size_t
508 blocksize;
509
510 void
511 *next;
512
513 /*
514 Split block.
515 */
516 next=(char *) block+size;
517 blocksize=SizeOfBlock(block)-size;
518 *BlockHeader(next)=blocksize;
519 *BlockFooter(next,blocksize)=blocksize;
520 InsertFreeBlock(next,AllocationPolicy(blocksize));
521 *BlockHeader(block)=size | (*BlockHeader(block) & ~SizeMask);
522 }
523 assert(size == SizeOfBlock(block));
524 *BlockHeader(NextBlock(block))|=PreviousBlockBit;
525 memory_pool.allocation+=size;
526 return(block);
527}
528#endif
529␌
530/*
531%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
532% %
533% %
534% %
535% A c q u i r e M a g i c k M e m o r y %
536% %
537% %
538% %
539%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
540%
541% AcquireMagickMemory() returns a pointer to a block of memory at least size
542% bytes suitably aligned for any use.
543%
544% The format of the AcquireMagickMemory method is:
545%
546% void *AcquireMagickMemory(const size_t size)
547%
548% A description of each parameter follows:
549%
550% o size: the size of the memory in bytes to allocate.
551%
552*/
553MagickExport void *AcquireMagickMemory(const size_t size)
554{
555 void
556 *memory;
557
558#if !defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
559 memory=memory_methods.acquire_memory_handler(size == 0 ? 1UL : size);
560#else
561 if (memory_semaphore == (SemaphoreInfo *) NULL)
562 ActivateSemaphoreInfo(&memory_semaphore);
563 if (free_segments == (DataSegmentInfo *) NULL)
564 {
565 LockSemaphoreInfo(memory_semaphore);
566 if (free_segments == (DataSegmentInfo *) NULL)
567 {
568 ssize_t
569 i;
570
571 assert(2*sizeof(size_t) > (size_t) (~SizeMask));
572 (void) memset(&memory_pool,0,sizeof(memory_pool));
573 memory_pool.allocation=SegmentSize;
574 memory_pool.blocks[MaxBlocks]=(void *) (-1);
575 for (i=0; i < MaxSegments; i++)
576 {
577 if (i != 0)
578 memory_pool.segment_pool[i].previous=
579 (&memory_pool.segment_pool[i-1]);
580 if (i != (MaxSegments-1))
581 memory_pool.segment_pool[i].next=(&memory_pool.segment_pool[i+1]);
582 }
583 free_segments=(&memory_pool.segment_pool[0]);
584 }
585 UnlockSemaphoreInfo(memory_semaphore);
586 }
587 LockSemaphoreInfo(memory_semaphore);
588 memory=AcquireBlock(size == 0 ? 1UL : size);
589 if (memory == (void *) NULL)
590 {
591 if (ExpandHeap(size == 0 ? 1UL : size) != MagickFalse)
592 memory=AcquireBlock(size == 0 ? 1UL : size);
593 }
594 UnlockSemaphoreInfo(memory_semaphore);
595#endif
596 return(memory);
597}
598␌
599/*
600%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
601% %
602% %
603% %
604% A c q u i r e C r i t i c a l M e m o r y %
605% %
606% %
607% %
608%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
609%
610% AcquireCriticalMemory() is just like AcquireMagickMemory(), throws a fatal
611% exception if the memory cannot be acquired.
612%
613% That is, AcquireCriticalMemory() returns a pointer to a block of memory that
614% is at least size bytes, and that is suitably aligned for any use; however,
615% if this is not possible, it throws an exception and terminates the program
616% as unceremoniously as possible.
617%
618% The format of the AcquireCriticalMemory method is:
619%
620% void *AcquireCriticalMemory(const size_t size)
621%
622% A description of each parameter follows:
623%
624% o size: the size (in bytes) of the memory to allocate.
625%
626*/
627MagickExport void *AcquireCriticalMemory(const size_t size)
628{
629 void
630 *memory;
631
632 /*
633 Fail if memory request cannot be fulfilled.
634 */
635 memory=AcquireMagickMemory(size);
636 if (memory == (void *) NULL)
637 ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
638 return(memory);
639}
640␌
641/*
642%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
643% %
644% %
645% %
646% A c q u i r e Q u a n t u m M e m o r y %
647% %
648% %
649% %
650%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
651%
652% AcquireQuantumMemory() returns a pointer to a block of memory at least
653% count * quantum bytes suitably aligned for any use.
654%
655% The format of the AcquireQuantumMemory method is:
656%
657% void *AcquireQuantumMemory(const size_t count,const size_t quantum)
658%
659% A description of each parameter follows:
660%
661% o count: the number of objects to allocate contiguously.
662%
663% o quantum: the size (in bytes) of each object.
664%
665*/
666MagickExport void *AcquireQuantumMemory(const size_t count,const size_t quantum)
667{
668 size_t
669 size;
670
671 if ((HeapOverflowSanityCheckGetSize(count,quantum,&size) != MagickFalse) ||
672 (size > GetMaxMemoryRequest()))
673 {
674 errno=ENOMEM;
675 return(NULL);
676 }
677 return(AcquireMagickMemory(size));
678}
679␌
680/*
681%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
682% %
683% %
684% %
685% A c q u i r e V i r t u a l M e m o r y %
686% %
687% %
688% %
689%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
690%
691% AcquireVirtualMemory() allocates a pointer to a block of memory at least
692% size bytes suitably aligned for any use. In addition to heap, it also
693% supports memory-mapped and file-based memory-mapped memory requests.
694%
695% The format of the AcquireVirtualMemory method is:
696%
697% MemoryInfo *AcquireVirtualMemory(const size_t count,const size_t quantum)
698%
699% A description of each parameter follows:
700%
701% o count: the number of objects to allocate contiguously.
702%
703% o quantum: the size (in bytes) of each object.
704%
705*/
706MagickExport MemoryInfo *AcquireVirtualMemory(const size_t count,
707 const size_t quantum)
708{
709 char
710 *value;
711
712 MemoryInfo
713 *memory_info;
714
715 size_t
716 size;
717
718 if (HeapOverflowSanityCheckGetSize(count,quantum,&size) != MagickFalse)
719 {
720 errno=ENOMEM;
721 return((MemoryInfo *) NULL);
722 }
723 if (virtual_anonymous_memory == 0)
724 {
725 virtual_anonymous_memory=1;
726 value=GetPolicyValue("system:memory-map");
727 if (LocaleCompare(value,"anonymous") == 0)
728 {
729 /*
730 The security policy sets anonymous mapping for the memory request.
731 */
732#if defined(MAGICKCORE_HAVE_MMAP) && defined(MAP_ANONYMOUS)
733 virtual_anonymous_memory=2;
734#endif
735 }
736 value=DestroyString(value);
737 }
738 memory_info=(MemoryInfo *) MagickAssumeAligned(AcquireAlignedMemory(1,
739 sizeof(*memory_info)));
740 if (memory_info == (MemoryInfo *) NULL)
741 ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
742 (void) memset(memory_info,0,sizeof(*memory_info));
743 memory_info->length=size;
744 memory_info->signature=MagickCoreSignature;
745 if ((virtual_anonymous_memory == 1) && (size <= GetMaxMemoryRequest()))
746 {
747 memory_info->blob=AcquireAlignedMemory(1,size);
748 if (memory_info->blob != NULL)
749 memory_info->type=AlignedVirtualMemory;
750 }
751 if (memory_info->blob == NULL)
752 {
753 /*
754 Acquire anonymous memory map.
755 */
756 memory_info->blob=NULL;
757 if (size <= GetMaxMemoryRequest())
758 memory_info->blob=MapBlob(-1,IOMode,0,size);
759 if (memory_info->blob != NULL)
760 memory_info->type=MapVirtualMemory;
761 else
762 {
763 int
764 file;
765
766 /*
767 Anonymous memory mapping failed, try file-backed memory mapping.
768 */
769 file=AcquireUniqueFileResource(memory_info->filename);
770 if (file != -1)
771 {
772 MagickOffsetType
773 offset;
774
775 offset=(MagickOffsetType) lseek(file,size-1,SEEK_SET);
776 if ((offset == (MagickOffsetType) (size-1)) &&
777 (write(file,"",1) == 1))
778 {
779#if !defined(MAGICKCORE_HAVE_POSIX_FALLOCATE)
780 memory_info->blob=MapBlob(file,IOMode,0,size);
781#else
782 if (posix_fallocate(file,0,(MagickOffsetType) size) == 0)
783 memory_info->blob=MapBlob(file,IOMode,0,size);
784#endif
785 if (memory_info->blob != NULL)
786 memory_info->type=MapVirtualMemory;
787 else
788 {
789 (void) RelinquishUniqueFileResource(
790 memory_info->filename);
791 *memory_info->filename='\0';
792 }
793 }
794 (void) close(file);
795 }
796 }
797 }
798 if (memory_info->blob == NULL)
799 {
800 memory_info->blob=AcquireQuantumMemory(1,size);
801 if (memory_info->blob != NULL)
802 memory_info->type=UnalignedVirtualMemory;
803 }
804 if (memory_info->blob == NULL)
805 memory_info=RelinquishVirtualMemory(memory_info);
806 return(memory_info);
807}
808␌
809/*
810%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
811% %
812% %
813% %
814% C o p y M a g i c k M e m o r y %
815% %
816% %
817% %
818%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
819%
820% CopyMagickMemory() copies size bytes from memory area source to the
821% destination. Copying between objects that overlap will take place
822% correctly. It returns destination.
823%
824% The format of the CopyMagickMemory method is:
825%
826% void *CopyMagickMemory(void *magick_restrict destination,
827% const void *magick_restrict source,const size_t size)
828%
829% A description of each parameter follows:
830%
831% o destination: the destination.
832%
833% o source: the source.
834%
835% o size: the size of the memory in bytes to allocate.
836%
837*/
838MagickExport void *CopyMagickMemory(void *magick_restrict destination,
839 const void *magick_restrict source,const size_t size)
840{
841 const unsigned char
842 *p;
843
844 unsigned char
845 *q;
846
847 assert(destination != (void *) NULL);
848 assert(source != (const void *) NULL);
849 p=(const unsigned char *) source;
850 q=(unsigned char *) destination;
851 if (((q+size) < p) || (q > (p+size)))
852 switch (size)
853 {
854 default: return(memcpy(destination,source,size));
855 case 8: *q++=(*p++); magick_fallthrough;
856 case 7: *q++=(*p++); magick_fallthrough;
857 case 6: *q++=(*p++); magick_fallthrough;
858 case 5: *q++=(*p++); magick_fallthrough;
859 case 4: *q++=(*p++); magick_fallthrough;
860 case 3: *q++=(*p++); magick_fallthrough;
861 case 2: *q++=(*p++); magick_fallthrough;
862 case 1: *q++=(*p++); magick_fallthrough;
863 case 0: return(destination);
864 }
865 return(memmove(destination,source,size));
866}
867␌
868/*
869%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
870% %
871% %
872% %
873+ D e s t r o y M a g i c k M e m o r y %
874% %
875% %
876% %
877%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
878%
879% DestroyMagickMemory() deallocates memory associated with the memory manager.
880%
881% The format of the DestroyMagickMemory method is:
882%
883% DestroyMagickMemory(void)
884%
885*/
886MagickExport void DestroyMagickMemory(void)
887{
888#if defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
889 ssize_t
890 i;
891
892 if (memory_semaphore == (SemaphoreInfo *) NULL)
893 ActivateSemaphoreInfo(&memory_semaphore);
894 LockSemaphoreInfo(memory_semaphore);
895 for (i=0; i < (ssize_t) memory_pool.number_segments; i++)
896 if (memory_pool.segments[i]->mapped == MagickFalse)
897 memory_methods.destroy_memory_handler(
898 memory_pool.segments[i]->allocation);
899 else
900 (void) UnmapBlob(memory_pool.segments[i]->allocation,
901 memory_pool.segments[i]->length);
902 free_segments=(DataSegmentInfo *) NULL;
903 (void) memset(&memory_pool,0,sizeof(memory_pool));
904 UnlockSemaphoreInfo(memory_semaphore);
905 DestroySemaphoreInfo(&memory_semaphore);
906#endif
907}
908␌
909#if defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
910/*
911%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
912% %
913% %
914% %
915+ E x p a n d H e a p %
916% %
917% %
918% %
919%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
920%
921% ExpandHeap() get more memory from the system. It returns MagickTrue on
922% success otherwise MagickFalse.
923%
924% The format of the ExpandHeap method is:
925%
926% MagickBooleanType ExpandHeap(size_t size)
927%
928% A description of each parameter follows:
929%
930% o size: the size of the memory in bytes we require.
931%
932*/
933static MagickBooleanType ExpandHeap(size_t size)
934{
935 DataSegmentInfo
936 *segment_info;
937
938 MagickBooleanType
939 mapped;
940
941 ssize_t
942 i;
943
944 void
945 *block;
946
947 size_t
948 blocksize;
949
950 void
951 *segment;
952
953 blocksize=((size+12*sizeof(size_t))+SegmentSize-1) & -SegmentSize;
954 assert(memory_pool.number_segments < MaxSegments);
955 segment=MapBlob(-1,IOMode,0,blocksize);
956 mapped=segment != (void *) NULL ? MagickTrue : MagickFalse;
957 if (segment == (void *) NULL)
958 segment=(void *) memory_methods.acquire_memory_handler(blocksize);
959 if (segment == (void *) NULL)
960 return(MagickFalse);
961 segment_info=(DataSegmentInfo *) free_segments;
962 free_segments=segment_info->next;
963 segment_info->mapped=mapped;
964 segment_info->length=blocksize;
965 segment_info->allocation=segment;
966 segment_info->bound=(char *) segment+blocksize;
967 i=(ssize_t) memory_pool.number_segments-1;
968 for ( ; (i >= 0) && (memory_pool.segments[i]->allocation > segment); i--)
969 memory_pool.segments[i+1]=memory_pool.segments[i];
970 memory_pool.segments[i+1]=segment_info;
971 memory_pool.number_segments++;
972 size=blocksize-12*sizeof(size_t);
973 block=(char *) segment_info->allocation+4*sizeof(size_t);
974 *BlockHeader(block)=size | PreviousBlockBit;
975 *BlockFooter(block,size)=size;
976 InsertFreeBlock(block,AllocationPolicy(size));
977 block=NextBlock(block);
978 assert(block < segment_info->bound);
979 *BlockHeader(block)=2*sizeof(size_t);
980 *BlockHeader(NextBlock(block))=PreviousBlockBit;
981 return(MagickTrue);
982}
983#endif
984␌
985/*
986%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
987% %
988% %
989% %
990% G e t M a g i c k M e m o r y M e t h o d s %
991% %
992% %
993% %
994%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
995%
996% GetMagickMemoryMethods() gets the methods to acquire, resize, and destroy
997% memory.
998%
999% The format of the GetMagickMemoryMethods() method is:
1000%
1001% void GetMagickMemoryMethods(AcquireMemoryHandler *acquire_memory_handler,
1002% ResizeMemoryHandler *resize_memory_handler,
1003% DestroyMemoryHandler *destroy_memory_handler)
1004%
1005% A description of each parameter follows:
1006%
1007% o acquire_memory_handler: method to acquire memory (e.g. malloc).
1008%
1009% o resize_memory_handler: method to resize memory (e.g. realloc).
1010%
1011% o destroy_memory_handler: method to destroy memory (e.g. free).
1012%
1013*/
1014MagickExport void GetMagickMemoryMethods(
1015 AcquireMemoryHandler *acquire_memory_handler,
1016 ResizeMemoryHandler *resize_memory_handler,
1017 DestroyMemoryHandler *destroy_memory_handler)
1018{
1019 assert(acquire_memory_handler != (AcquireMemoryHandler *) NULL);
1020 assert(resize_memory_handler != (ResizeMemoryHandler *) NULL);
1021 assert(destroy_memory_handler != (DestroyMemoryHandler *) NULL);
1022 *acquire_memory_handler=memory_methods.acquire_memory_handler;
1023 *resize_memory_handler=memory_methods.resize_memory_handler;
1024 *destroy_memory_handler=memory_methods.destroy_memory_handler;
1025}
1026␌
1027/*
1028%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1029% %
1030% %
1031% %
1032+ G e t M a x M e m o r y R e q u e s t %
1033% %
1034% %
1035% %
1036%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1037%
1038% GetMaxMemoryRequest() returns the max memory request value.
1039%
1040% The format of the GetMaxMemoryRequest method is:
1041%
1042% size_t GetMaxMemoryRequest(void)
1043%
1044*/
1045MagickExport size_t GetMaxMemoryRequest(void)
1046{
1047#define MinMemoryRequest "16MiB"
1048
1049 if (max_memory_request == 0)
1050 {
1051 char
1052 *value;
1053
1054 max_memory_request=(size_t) MAGICK_SSIZE_MAX;
1055 value=GetPolicyValue("system:max-memory-request");
1056 if (value != (char *) NULL)
1057 {
1058 /*
1059 The security policy sets a max memory request limit.
1060 */
1061 max_memory_request=MagickMax(StringToSizeType(value,100.0),
1062 StringToSizeType(MinMemoryRequest,100.0));
1063 value=DestroyString(value);
1064 }
1065 }
1066 return(MagickMin(max_memory_request,(size_t) MAGICK_SSIZE_MAX));
1067}
1068␌
1069/*
1070%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1071% %
1072% %
1073% %
1074% G e t V i r t u a l M e m o r y B l o b %
1075% %
1076% %
1077% %
1078%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1079%
1080% GetVirtualMemoryBlob() returns the virtual memory blob associated with the
1081% specified MemoryInfo structure.
1082%
1083% The format of the GetVirtualMemoryBlob method is:
1084%
1085% void *GetVirtualMemoryBlob(const MemoryInfo *memory_info)
1086%
1087% A description of each parameter follows:
1088%
1089% o memory_info: The MemoryInfo structure.
1090*/
1091MagickExport void *GetVirtualMemoryBlob(const MemoryInfo *memory_info)
1092{
1093 assert(memory_info != (const MemoryInfo *) NULL);
1094 assert(memory_info->signature == MagickCoreSignature);
1095 return(memory_info->blob);
1096}
1097␌
1098/*
1099%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1100% %
1101% %
1102% %
1103% R e l i n q u i s h A l i g n e d M e m o r y %
1104% %
1105% %
1106% %
1107%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1108%
1109% RelinquishAlignedMemory() frees memory acquired with AcquireAlignedMemory()
1110% or reuse.
1111%
1112% The format of the RelinquishAlignedMemory method is:
1113%
1114% void *RelinquishAlignedMemory(void *memory)
1115%
1116% A description of each parameter follows:
1117%
1118% o memory: A pointer to a block of memory to free for reuse.
1119%
1120*/
1121MagickExport void *RelinquishAlignedMemory(void *memory)
1122{
1123 if (memory == (void *) NULL)
1124 return((void *) NULL);
1125 if (memory_methods.relinquish_aligned_memory_handler != (RelinquishAlignedMemoryHandler) NULL)
1126 {
1127 memory_methods.relinquish_aligned_memory_handler(memory);
1128 return(NULL);
1129 }
1130#if defined(MAGICKCORE_HAVE_ALIGNED_MALLOC) || defined(MAGICKCORE_HAVE_POSIX_MEMALIGN)
1131 free(memory);
1132#elif defined(MAGICKCORE_HAVE__ALIGNED_MALLOC)
1133 _aligned_free(memory);
1134#else
1135 RelinquishMagickMemory(actual_base_address(memory));
1136#endif
1137 return(NULL);
1138}
1139␌
1140/*
1141%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1142% %
1143% %
1144% %
1145% R e l i n q u i s h M a g i c k M e m o r y %
1146% %
1147% %
1148% %
1149%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1150%
1151% RelinquishMagickMemory() frees memory acquired with AcquireMagickMemory()
1152% or AcquireQuantumMemory() for reuse.
1153%
1154% The format of the RelinquishMagickMemory method is:
1155%
1156% void *RelinquishMagickMemory(void *memory)
1157%
1158% A description of each parameter follows:
1159%
1160% o memory: A pointer to a block of memory to free for reuse.
1161%
1162*/
1163MagickExport void *RelinquishMagickMemory(void *memory)
1164{
1165 if (memory == (void *) NULL)
1166 return((void *) NULL);
1167#if !defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
1168 memory_methods.destroy_memory_handler(memory);
1169#else
1170 LockSemaphoreInfo(memory_semaphore);
1171 assert((SizeOfBlock(memory) % (4*sizeof(size_t))) == 0);
1172 assert((*BlockHeader(NextBlock(memory)) & PreviousBlockBit) != 0);
1173 if ((*BlockHeader(memory) & PreviousBlockBit) == 0)
1174 {
1175 void
1176 *previous;
1177
1178 /*
1179 Coalesce with previous adjacent block.
1180 */
1181 previous=PreviousBlock(memory);
1182 RemoveFreeBlock(previous,AllocationPolicy(SizeOfBlock(previous)));
1183 *BlockHeader(previous)=(SizeOfBlock(previous)+SizeOfBlock(memory)) |
1184 (*BlockHeader(previous) & ~SizeMask);
1185 memory=previous;
1186 }
1187 if ((*BlockHeader(NextBlock(NextBlock(memory))) & PreviousBlockBit) == 0)
1188 {
1189 void
1190 *next;
1191
1192 /*
1193 Coalesce with next adjacent block.
1194 */
1195 next=NextBlock(memory);
1196 RemoveFreeBlock(next,AllocationPolicy(SizeOfBlock(next)));
1197 *BlockHeader(memory)=(SizeOfBlock(memory)+SizeOfBlock(next)) |
1198 (*BlockHeader(memory) & ~SizeMask);
1199 }
1200 *BlockFooter(memory,SizeOfBlock(memory))=SizeOfBlock(memory);
1201 *BlockHeader(NextBlock(memory))&=(~PreviousBlockBit);
1202 InsertFreeBlock(memory,AllocationPolicy(SizeOfBlock(memory)));
1203 UnlockSemaphoreInfo(memory_semaphore);
1204#endif
1205 return((void *) NULL);
1206}
1207␌
1208/*
1209%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1210% %
1211% %
1212% %
1213% R e l i n q u i s h V i r t u a l M e m o r y %
1214% %
1215% %
1216% %
1217%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1218%
1219% RelinquishVirtualMemory() frees memory acquired with AcquireVirtualMemory().
1220%
1221% The format of the RelinquishVirtualMemory method is:
1222%
1223% MemoryInfo *RelinquishVirtualMemory(MemoryInfo *memory_info)
1224%
1225% A description of each parameter follows:
1226%
1227% o memory_info: A pointer to a block of memory to free for reuse.
1228%
1229*/
1230MagickExport MemoryInfo *RelinquishVirtualMemory(MemoryInfo *memory_info)
1231{
1232 assert(memory_info != (MemoryInfo *) NULL);
1233 assert(memory_info->signature == MagickCoreSignature);
1234 if (memory_info->blob != (void *) NULL)
1235 switch (memory_info->type)
1236 {
1237 case AlignedVirtualMemory:
1238 {
1239 (void) ShredMagickMemory(memory_info->blob,memory_info->length);
1240 memory_info->blob=RelinquishAlignedMemory(memory_info->blob);
1241 break;
1242 }
1243 case MapVirtualMemory:
1244 {
1245 (void) UnmapBlob(memory_info->blob,memory_info->length);
1246 memory_info->blob=NULL;
1247 if (*memory_info->filename != '\0')
1248 (void) RelinquishUniqueFileResource(memory_info->filename);
1249 break;
1250 }
1251 case UnalignedVirtualMemory:
1252 default:
1253 {
1254 (void) ShredMagickMemory(memory_info->blob,memory_info->length);
1255 memory_info->blob=RelinquishMagickMemory(memory_info->blob);
1256 break;
1257 }
1258 }
1259 memory_info->signature=(~MagickCoreSignature);
1260 memory_info=(MemoryInfo *) RelinquishAlignedMemory(memory_info);
1261 return(memory_info);
1262}
1263␌
1264/*
1265%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1266% %
1267% %
1268% %
1269% R e s e t M a g i c k M e m o r y %
1270% %
1271% %
1272% %
1273%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1274%
1275% ResetMagickMemory() fills the first size bytes of the memory area pointed to
1276% by memory with the constant byte c. We use a volatile pointer when
1277% updating the byte string. Most compilers will avoid optimizing away access
1278% to a volatile pointer, even if the pointer appears to be unused after the
1279% call.
1280%
1281% The format of the ResetMagickMemory method is:
1282%
1283% void *ResetMagickMemory(void *memory,int c,const size_t size)
1284%
1285% A description of each parameter follows:
1286%
1287% o memory: a pointer to a memory allocation.
1288%
1289% o c: set the memory to this value.
1290%
1291% o size: size of the memory to reset.
1292%
1293*/
1294MagickExport void *ResetMagickMemory(void *memory,int c,const size_t size)
1295{
1296 volatile unsigned char
1297 *p = (volatile unsigned char *) memory;
1298
1299 size_t
1300 n = size;
1301
1302 assert(memory != (void *) NULL);
1303 while (n-- != 0)
1304 *p++=(unsigned char) c;
1305 return(memory);
1306}
1307␌
1308/*
1309%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1310% %
1311% %
1312% %
1313+ R e s e t M a x M e m o r y R e q u e s t %
1314% %
1315% %
1316% %
1317%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1318%
1319% ResetMaxMemoryRequest() resets the max_memory_request value.
1320%
1321% The format of the ResetMaxMemoryRequest method is:
1322%
1323% void ResetMaxMemoryRequest(void)
1324%
1325*/
1326MagickPrivate void ResetMaxMemoryRequest(void)
1327{
1328 max_memory_request=0;
1329}
1330␌
1331/*
1332%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1333% %
1334% %
1335% %
1336+ 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 %
1337% %
1338% %
1339% %
1340%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1341%
1342% ResetVirtualAnonymousMemory() resets the virtual_anonymous_memory value.
1343%
1344% The format of the ResetVirtualAnonymousMemory method is:
1345%
1346% void ResetVirtualAnonymousMemory(void)
1347%
1348*/
1349MagickPrivate void ResetVirtualAnonymousMemory(void)
1350{
1351 virtual_anonymous_memory=0;
1352}
1353␌
1354/*
1355%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1356% %
1357% %
1358% %
1359% R e s i z e M a g i c k M e m o r y %
1360% %
1361% %
1362% %
1363%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1364%
1365% ResizeMagickMemory() changes the size of the memory and returns a pointer to
1366% the (possibly moved) block. The contents will be unchanged up to the
1367% lesser of the new and old sizes.
1368%
1369% The format of the ResizeMagickMemory method is:
1370%
1371% void *ResizeMagickMemory(void *memory,const size_t size)
1372%
1373% A description of each parameter follows:
1374%
1375% o memory: A pointer to a memory allocation.
1376%
1377% o size: the new size of the allocated memory.
1378%
1379*/
1380
1381#if defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
1382static inline void *ResizeBlock(void *block,size_t size)
1383{
1384 void
1385 *memory;
1386
1387 if (block == (void *) NULL)
1388 return(AcquireBlock(size));
1389 memory=AcquireBlock(size);
1390 if (memory == (void *) NULL)
1391 return((void *) NULL);
1392 if (size <= (SizeOfBlock(block)-sizeof(size_t)))
1393 (void) memcpy(memory,block,size);
1394 else
1395 (void) memcpy(memory,block,SizeOfBlock(block)-sizeof(size_t));
1396 memory_pool.allocation+=size;
1397 return(memory);
1398}
1399#endif
1400
1401MagickExport void *ResizeMagickMemory(void *memory,const size_t size)
1402{
1403 void
1404 *block;
1405
1406 if (memory == (void *) NULL)
1407 return(AcquireMagickMemory(size));
1408#if !defined(MAGICKCORE_ANONYMOUS_MEMORY_SUPPORT)
1409 block=memory_methods.resize_memory_handler(memory,size == 0 ? 1UL : size);
1410 if (block == (void *) NULL)
1411 memory=RelinquishMagickMemory(memory);
1412#else
1413 LockSemaphoreInfo(memory_semaphore);
1414 block=ResizeBlock(memory,size == 0 ? 1UL : size);
1415 if (block == (void *) NULL)
1416 {
1417 if (ExpandHeap(size == 0 ? 1UL : size) == MagickFalse)
1418 {
1419 UnlockSemaphoreInfo(memory_semaphore);
1420 memory=RelinquishMagickMemory(memory);
1421 ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
1422 }
1423 block=ResizeBlock(memory,size == 0 ? 1UL : size);
1424 assert(block != (void *) NULL);
1425 }
1426 UnlockSemaphoreInfo(memory_semaphore);
1427 memory=RelinquishMagickMemory(memory);
1428#endif
1429 return(block);
1430}
1431␌
1432/*
1433%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1434% %
1435% %
1436% %
1437% R e s i z e Q u a n t u m M e m o r y %
1438% %
1439% %
1440% %
1441%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1442%
1443% ResizeQuantumMemory() changes the size of the memory and returns a pointer
1444% to the (possibly moved) block. The contents will be unchanged up to the
1445% lesser of the new and old sizes.
1446%
1447% The format of the ResizeQuantumMemory method is:
1448%
1449% void *ResizeQuantumMemory(void *memory,const size_t count,
1450% const size_t quantum)
1451%
1452% A description of each parameter follows:
1453%
1454% o memory: A pointer to a memory allocation.
1455%
1456% o count: the number of objects to allocate contiguously.
1457%
1458% o quantum: the size (in bytes) of each object.
1459%
1460*/
1461MagickExport void *ResizeQuantumMemory(void *memory,const size_t count,
1462 const size_t quantum)
1463{
1464 size_t
1465 size;
1466
1467 if ((HeapOverflowSanityCheckGetSize(count,quantum,&size) != MagickFalse) ||
1468 (size > GetMaxMemoryRequest()))
1469 {
1470 errno=ENOMEM;
1471 memory=RelinquishMagickMemory(memory);
1472 return(NULL);
1473 }
1474 if (size > GetMaxMemoryRequest())
1475 return(NULL);
1476 return(ResizeMagickMemory(memory,size));
1477}
1478␌
1479/*
1480%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1481% %
1482% %
1483% %
1484% 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 %
1485% %
1486% %
1487% %
1488%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1489%
1490% SetMagickAlignedMemoryMethods() sets the methods to acquire and relinquish
1491% aligned memory.
1492%
1493% The format of the SetMagickAlignedMemoryMethods() method is:
1494%
1495% SetMagickAlignedMemoryMethods(
1496% AcquireAlignedMemoryHandler acquire_aligned_memory_handler,
1497% RelinquishAlignedMemoryHandler relinquish_aligned_memory_handler)
1498%
1499% A description of each parameter follows:
1500%
1501% o acquire_memory_handler: method to acquire aligned memory.
1502%
1503% o relinquish_aligned_memory_handler: method to relinquish aligned memory.
1504%
1505*/
1506MagickExport void SetMagickAlignedMemoryMethods(
1507 AcquireAlignedMemoryHandler acquire_aligned_memory_handler,
1508 RelinquishAlignedMemoryHandler relinquish_aligned_memory_handler)
1509{
1510 memory_methods.acquire_aligned_memory_handler=acquire_aligned_memory_handler;
1511 memory_methods.relinquish_aligned_memory_handler=
1512 relinquish_aligned_memory_handler;
1513}
1514␌
1515/*
1516%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1517% %
1518% %
1519% %
1520% S e t M a g i c k M e m o r y M e t h o d s %
1521% %
1522% %
1523% %
1524%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1525%
1526% SetMagickMemoryMethods() sets the methods to acquire, resize, and destroy
1527% memory. Your custom memory methods must be set prior to the
1528% MagickCoreGenesis() method.
1529%
1530% The format of the SetMagickMemoryMethods() method is:
1531%
1532% SetMagickMemoryMethods(AcquireMemoryHandler acquire_memory_handler,
1533% ResizeMemoryHandler resize_memory_handler,
1534% DestroyMemoryHandler destroy_memory_handler)
1535%
1536% A description of each parameter follows:
1537%
1538% o acquire_memory_handler: method to acquire memory (e.g. malloc).
1539%
1540% o resize_memory_handler: method to resize memory (e.g. realloc).
1541%
1542% o destroy_memory_handler: method to destroy memory (e.g. free).
1543%
1544*/
1545MagickExport void SetMagickMemoryMethods(
1546 AcquireMemoryHandler acquire_memory_handler,
1547 ResizeMemoryHandler resize_memory_handler,
1548 DestroyMemoryHandler destroy_memory_handler)
1549{
1550 /*
1551 Set memory methods.
1552 */
1553 if (acquire_memory_handler != (AcquireMemoryHandler) NULL)
1554 memory_methods.acquire_memory_handler=acquire_memory_handler;
1555 if (resize_memory_handler != (ResizeMemoryHandler) NULL)
1556 memory_methods.resize_memory_handler=resize_memory_handler;
1557 if (destroy_memory_handler != (DestroyMemoryHandler) NULL)
1558 memory_methods.destroy_memory_handler=destroy_memory_handler;
1559}
1560␌
1561/*
1562%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1563% %
1564% %
1565% %
1566+ S e t M a x M e m o r y R e q u e s t %
1567% %
1568% %
1569% %
1570%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1571%
1572% SetMaxMemoryRequest() sets the max_memory_request value.
1573%
1574% The format of the ResetMaxMemoryRequest method is:
1575%
1576% void SetMaxMemoryRequest(const MagickSizeType limit)
1577%
1578% A description of each parameter follows:
1579%
1580% o limit: the maximum memory request limit.
1581%
1582*/
1583MagickPrivate void SetMaxMemoryRequest(const MagickSizeType limit)
1584{
1585 max_memory_request=MagickMin(limit,GetMaxMemoryRequest());
1586}
1587␌
1588/*
1589%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1590% %
1591% %
1592% %
1593% S h r e d F i l e %
1594% %
1595% %
1596% %
1597%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1598%
1599% ShredMagickMemory() overwrites the specified memory buffer with random data.
1600% The overwrite is optional and is only required to help keep the contents of
1601% the memory buffer private.
1602%
1603% The format of the ShredMagickMemory method is:
1604%
1605% MagickBooleanType ShredMagickMemory(void *memory,const size_t length)
1606%
1607% A description of each parameter follows.
1608%
1609% o memory: Specifies the memory buffer.
1610%
1611% o length: Specifies the length of the memory buffer.
1612%
1613*/
1614MagickPrivate MagickBooleanType ShredMagickMemory(void *memory,
1615 const size_t length)
1616{
1617 RandomInfo
1618 *random_info;
1619
1620 size_t
1621 quantum;
1622
1623 ssize_t
1624 i;
1625
1626 StringInfo
1627 *key;
1628
1629 static ssize_t
1630 passes = -1;
1631
1632 if ((memory == NULL) || (length == 0))
1633 return(MagickFalse);
1634 if (passes == -1)
1635 {
1636 char
1637 *property;
1638
1639 passes=0;
1640 property=GetEnvironmentValue("MAGICK_SHRED_PASSES");
1641 if (property != (char *) NULL)
1642 {
1643 passes=(ssize_t) StringToInteger(property);
1644 property=DestroyString(property);
1645 }
1646 property=GetPolicyValue("system:shred");
1647 if (property != (char *) NULL)
1648 {
1649 passes=(ssize_t) StringToInteger(property);
1650 property=DestroyString(property);
1651 }
1652 }
1653 if (passes == 0)
1654 return(MagickTrue);
1655 /*
1656 Overwrite the memory buffer with random data.
1657 */
1658 quantum=(size_t) MagickMin(length,MagickMinBufferExtent);
1659 random_info=AcquireRandomInfo();
1660 key=GetRandomKey(random_info,quantum);
1661 for (i=0; i < passes; i++)
1662 {
1663 size_t
1664 j;
1665
1666 unsigned char
1667 *p = (unsigned char *) memory;
1668
1669 for (j=0; j < length; j+=quantum)
1670 {
1671 if (i != 0)
1672 SetRandomKey(random_info,quantum,GetStringInfoDatum(key));
1673 (void) memcpy(p,GetStringInfoDatum(key),(size_t)
1674 MagickMin(quantum,length-j));
1675 p+=(ptrdiff_t) quantum;
1676 }
1677 if (j < length)
1678 break;
1679 }
1680 key=DestroyStringInfo(key);
1681 random_info=DestroyRandomInfo(random_info);
1682 return(i < passes ? MagickFalse : MagickTrue);
1683}
_DataSegmentInfo
Definition memory.c:130
_MagickMemoryMethods
Definition memory.c:147
_MemoryInfo
Definition memory.c:165
_MemoryPool
Definition memory.c:183
_RandomInfo
Definition random.c:82
_StringInfo
Definition string_.h:30