granicus.if.org Git - imagemagick/blob - MagickCore/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 %                                John Cristy                                  %
  17 %                                 July 1998                                   %
  18 %                                                                             %
  19 %                                                                             %
  20 %  Copyright 1999-2013 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 %    http://www.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 %  Segregate our memory requirements from any program that calls our API.  This
  37 %  should help reduce the risk of others changing our program state or causing
  38 %  memory corruption.
  39 %
  40 %  Our custom memory allocation manager implements a best-fit allocation policy
  41 %  using segregated free lists.  It uses a linear distribution of size classes
  42 %  for lower sizes and a power of two distribution of size classes at higher
  43 %  sizes.  It is based on the paper, "Fast Memory Allocation using Lazy Fits."
  44 %  written by Yoo C. Chung.
  45 %
  46 %  By default, ANSI memory methods are called (e.g. malloc).  Use the
  47 %  custom memory allocator by defining MAGICKCORE_ZERO_CONFIGURATION_SUPPORT
  48 %  to allocate memory with private anonymous mapping rather than from the
  49 %  heap.
  50 %
  51 */
  52 \f
  53 /*
  54   Include declarations.
  55 */
  56 #include "MagickCore/studio.h"
  57 #include "MagickCore/blob.h"
  58 #include "MagickCore/blob-private.h"
  59 #include "MagickCore/exception.h"
  60 #include "MagickCore/exception-private.h"
  61 #include "MagickCore/memory_.h"
  62 #include "MagickCore/memory-private.h"
  63 #include "MagickCore/resource_.h"
  64 #include "MagickCore/semaphore.h"
  65 #include "MagickCore/string_.h"
  66 #include "MagickCore/utility-private.h"
  67 \f
  68 /*
  69   Define declarations.
  70 */
  71 #define BlockFooter(block,size) \
  72   ((size_t *) ((char *) (block)+(size)-2*sizeof(size_t)))
  73 #define BlockHeader(block)  ((size_t *) (block)-1)
  74 #define BlockSize  4096
  75 #define BlockThreshold  1024
  76 #define MaxBlockExponent  16
  77 #define MaxBlocks ((BlockThreshold/(4*sizeof(size_t)))+MaxBlockExponent+1)
  78 #define MaxSegments  1024
  79 #define MemoryGuard  ((0xdeadbeef << 31)+0xdeafdeed)
  80 #define NextBlock(block)  ((char *) (block)+SizeOfBlock(block))
  81 #define NextBlockInList(block)  (*(void **) (block))
  82 #define PreviousBlock(block)  ((char *) (block)-(*((size_t *) (block)-2)))
  83 #define PreviousBlockBit  0x01
  84 #define PreviousBlockInList(block)  (*((void **) (block)+1))
  85 #define SegmentSize  (2*1024*1024)
  86 #define SizeMask  (~0x01)
  87 #define SizeOfBlock(block)  (*BlockHeader(block) & SizeMask)
  88 \f
  89 /*
  90   Typedef declarations.
  91 */
  92 typedef struct _DataSegmentInfo
  93 {
  94   void
  95     *allocation,
  96     *bound;
  97
  98   MagickBooleanType
  99     mapped;
 100
 101   size_t
 102     length;
 103
 104   struct _DataSegmentInfo
 105     *previous,
 106     *next;
 107 } DataSegmentInfo;
 108
 109 typedef struct _MagickMemoryMethods
 110 {
 111   AcquireMemoryHandler
 112     acquire_memory_handler;
 113
 114   ResizeMemoryHandler
 115     resize_memory_handler;
 116
 117   DestroyMemoryHandler
 118     destroy_memory_handler;
 119 } MagickMemoryMethods;
 120
 121 struct _MemoryInfo
 122 {
 123   char
 124     filename[MaxTextExtent];
 125
 126   MagickBooleanType
 127     mapped;
 128
 129   size_t
 130     length;
 131
 132   void
 133     *blob;
 134
 135   size_t
 136     signature;
 137 };
 138
 139 typedef struct _MemoryPool
 140 {
 141   size_t
 142     allocation;
 143
 144   void
 145     *blocks[MaxBlocks+1];
 146
 147   size_t
 148     number_segments;
 149
 150   DataSegmentInfo
 151     *segments[MaxSegments],
 152     segment_pool[MaxSegments];
 153 } MemoryPool;
 154 \f
 155 /*
 156   Global declarations.
 157 */
 158 static MagickMemoryMethods
 159   memory_methods =
 160   {
 161     (AcquireMemoryHandler) malloc,
 162     (ResizeMemoryHandler) realloc,
 163     (DestroyMemoryHandler) free
 164   };
 165
 166 #if defined(MAGICKCORE_ZERO_CONFIGURATION_SUPPORT)
 167 static MemoryPool
 168   memory_pool;
 169
 170 static SemaphoreInfo
 171   *memory_semaphore = (SemaphoreInfo *) NULL;
 172
 173 static volatile DataSegmentInfo
 174   *free_segments = (DataSegmentInfo *) NULL;
 175 \f
 176 /*
 177   Forward declarations.
 178 */
 179 static MagickBooleanType
 180   ExpandHeap(size_t);
 181 #endif
 182 \f
 183 /*
 184 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 185 %                                                                             %
 186 %                                                                             %
 187 %                                                                             %
 188 %   A c q u i r e A l i g n e d M e m o r y                                   %
 189 %                                                                             %
 190 %                                                                             %
 191 %                                                                             %
 192 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 193 %
 194 %  AcquireAlignedMemory() returns a pointer to a block of memory at least size
 195 %  bytes whose address is a multiple of 16*sizeof(void *).
 196 %
 197 %  The format of the AcquireAlignedMemory method is:
 198 %
 199 %      void *AcquireAlignedMemory(const size_t count,const size_t quantum)
 200 %
 201 %  A description of each parameter follows:
 202 %
 203 %    o count: the number of quantum elements to allocate.
 204 %
 205 %    o quantum: the number of bytes in each quantum.
 206 %
 207 */
 208 MagickExport void *AcquireAlignedMemory(const size_t count,const size_t quantum)
 209 {
 210 #define AlignedExtent(size,alignment) \
 211   (((size)+((alignment)-1)) & ~((alignment)-1))
 212
 213   size_t
 214     alignment,
 215     extent,
 216     size;
 217
 218   void
 219     *memory;
 220
 221   size=count*quantum;
 222   if ((count == 0) || (quantum != (size/count)))
 223     {
 224       errno=ENOMEM;
 225       return((void *) NULL);
 226     }
 227   memory=NULL;
 228   alignment=CACHE_LINE_SIZE;
 229   extent=AlignedExtent(size,alignment);
 230   if ((size == 0) || (alignment < sizeof(void *)) || (extent < size))
 231     return((void *) NULL);
 232 #if defined(MAGICKCORE_HAVE_POSIX_MEMALIGN)
 233   if (posix_memalign(&memory,alignment,extent) != 0)
 234     memory=NULL;
 235 #elif defined(MAGICKCORE_HAVE__ALIGNED_MALLOC)
 236   memory=_aligned_malloc(extent,alignment);
 237 #else
 238   {
 239     void
 240       *p;
 241
 242     extent=(size+alignment-1)+sizeof(void *);
 243     if (extent > size)
 244       {
 245         p=malloc(extent);
 246         if (p != NULL)
 247           {
 248             memory=(void *) AlignedExtent((size_t) p+sizeof(void *),alignment);
 249             *((void **) memory-1)=p;
 250           }
 251       }
 252   }
 253 #endif
 254   return(memory);
 255 }
 256 \f
 257 #if defined(MAGICKCORE_ZERO_CONFIGURATION_SUPPORT)
 258 /*
 259 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 260 %                                                                             %
 261 %                                                                             %
 262 %                                                                             %
 263 +   A c q u i r e B l o c k                                                   %
 264 %                                                                             %
 265 %                                                                             %
 266 %                                                                             %
 267 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 268 %
 269 %  AcquireBlock() returns a pointer to a block of memory at least size bytes
 270 %  suitably aligned for any use.
 271 %
 272 %  The format of the AcquireBlock method is:
 273 %
 274 %      void *AcquireBlock(const size_t size)
 275 %
 276 %  A description of each parameter follows:
 277 %
 278 %    o size: the size of the memory in bytes to allocate.
 279 %
 280 */
 281
 282 static inline size_t AllocationPolicy(size_t size)
 283 {
 284   register size_t
 285     blocksize;
 286
 287   /*
 288     The linear distribution.
 289   */
 290   assert(size != 0);
 291   assert(size % (4*sizeof(size_t)) == 0);
 292   if (size <= BlockThreshold)
 293     return(size/(4*sizeof(size_t)));
 294   /*
 295     Check for the largest block size.
 296   */
 297   if (size > (size_t) (BlockThreshold*(1L << (MaxBlockExponent-1L))))
 298     return(MaxBlocks-1L);
 299   /*
 300     Otherwise use a power of two distribution.
 301   */
 302   blocksize=BlockThreshold/(4*sizeof(size_t));
 303   for ( ; size > BlockThreshold; size/=2)
 304     blocksize++;
 305   assert(blocksize > (BlockThreshold/(4*sizeof(size_t))));
 306   assert(blocksize < (MaxBlocks-1L));
 307   return(blocksize);
 308 }
 309
 310 static inline void InsertFreeBlock(void *block,const size_t i)
 311 {
 312   register void
 313     *next,
 314     *previous;
 315
 316   size_t
 317     size;
 318
 319   size=SizeOfBlock(block);
 320   previous=(void *) NULL;
 321   next=memory_pool.blocks[i];
 322   while ((next != (void *) NULL) && (SizeOfBlock(next) < size))
 323   {
 324     previous=next;
 325     next=NextBlockInList(next);
 326   }
 327   PreviousBlockInList(block)=previous;
 328   NextBlockInList(block)=next;
 329   if (previous != (void *) NULL)
 330     NextBlockInList(previous)=block;
 331   else
 332     memory_pool.blocks[i]=block;
 333   if (next != (void *) NULL)
 334     PreviousBlockInList(next)=block;
 335 }
 336
 337 static inline void RemoveFreeBlock(void *block,const size_t i)
 338 {
 339   register void
 340     *next,
 341     *previous;
 342
 343   next=NextBlockInList(block);
 344   previous=PreviousBlockInList(block);
 345   if (previous == (void *) NULL)
 346     memory_pool.blocks[i]=next;
 347   else
 348     NextBlockInList(previous)=next;
 349   if (next != (void *) NULL)
 350     PreviousBlockInList(next)=previous;
 351 }
 352
 353 static void *AcquireBlock(size_t size)
 354 {
 355   register size_t
 356     i;
 357
 358   register void
 359     *block;
 360
 361   /*
 362     Find free block.
 363   */
 364   size=(size_t) (size+sizeof(size_t)+6*sizeof(size_t)-1) & -(4U*sizeof(size_t));
 365   i=AllocationPolicy(size);
 366   block=memory_pool.blocks[i];
 367   while ((block != (void *) NULL) && (SizeOfBlock(block) < size))
 368     block=NextBlockInList(block);
 369   if (block == (void *) NULL)
 370     {
 371       i++;
 372       while (memory_pool.blocks[i] == (void *) NULL)
 373         i++;
 374       block=memory_pool.blocks[i];
 375       if (i >= MaxBlocks)
 376         return((void *) NULL);
 377     }
 378   assert((*BlockHeader(NextBlock(block)) & PreviousBlockBit) == 0);
 379   assert(SizeOfBlock(block) >= size);
 380   RemoveFreeBlock(block,AllocationPolicy(SizeOfBlock(block)));
 381   if (SizeOfBlock(block) > size)
 382     {
 383       size_t
 384         blocksize;
 385
 386       void
 387         *next;
 388
 389       /*
 390         Split block.
 391       */
 392       next=(char *) block+size;
 393       blocksize=SizeOfBlock(block)-size;
 394       *BlockHeader(next)=blocksize;
 395       *BlockFooter(next,blocksize)=blocksize;
 396       InsertFreeBlock(next,AllocationPolicy(blocksize));
 397       *BlockHeader(block)=size | (*BlockHeader(block) & ~SizeMask);
 398     }
 399   assert(size == SizeOfBlock(block));
 400   *BlockHeader(NextBlock(block))|=PreviousBlockBit;
 401   memory_pool.allocation+=size;
 402   return(block);
 403 }
 404 #endif
 405 \f
 406 /*
 407 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 408 %                                                                             %
 409 %                                                                             %
 410 %                                                                             %
 411 %   A c q u i r e M a g i c k M e m o r y                                     %
 412 %                                                                             %
 413 %                                                                             %
 414 %                                                                             %
 415 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 416 %
 417 %  AcquireMagickMemory() returns a pointer to a block of memory at least size
 418 %  bytes suitably aligned for any use.
 419 %
 420 %  The format of the AcquireMagickMemory method is:
 421 %
 422 %      void *AcquireMagickMemory(const size_t size)
 423 %
 424 %  A description of each parameter follows:
 425 %
 426 %    o size: the size of the memory in bytes to allocate.
 427 %
 428 */
 429 MagickExport void *AcquireMagickMemory(const size_t size)
 430 {
 431   register void
 432     *memory;
 433
 434 #if !defined(MAGICKCORE_ZERO_CONFIGURATION_SUPPORT)
 435   memory=memory_methods.acquire_memory_handler(size == 0 ? 1UL : size);
 436 #else
 437   if (memory_semaphore == (SemaphoreInfo *) NULL)
 438     AcquireSemaphoreInfo(&memory_semaphore);
 439   if (free_segments == (DataSegmentInfo *) NULL)
 440     {
 441       LockSemaphoreInfo(memory_semaphore);
 442       if (free_segments == (DataSegmentInfo *) NULL)
 443         {
 444           register ssize_t
 445             i;
 446
 447           assert(2*sizeof(size_t) > (size_t) (~SizeMask));
 448           (void) ResetMagickMemory(&memory_pool,0,sizeof(memory_pool));
 449           memory_pool.allocation=SegmentSize;
 450           memory_pool.blocks[MaxBlocks]=(void *) (-1);
 451           for (i=0; i < MaxSegments; i++)
 452           {
 453             if (i != 0)
 454               memory_pool.segment_pool[i].previous=
 455                 (&memory_pool.segment_pool[i-1]);
 456             if (i != (MaxSegments-1))
 457               memory_pool.segment_pool[i].next=(&memory_pool.segment_pool[i+1]);
 458           }
 459           free_segments=(&memory_pool.segment_pool[0]);
 460         }
 461       UnlockSemaphoreInfo(memory_semaphore);
 462     }
 463   LockSemaphoreInfo(memory_semaphore);
 464   memory=AcquireBlock(size == 0 ? 1UL : size);
 465   if (memory == (void *) NULL)
 466     {
 467       if (ExpandHeap(size == 0 ? 1UL : size) != MagickFalse)
 468         memory=AcquireBlock(size == 0 ? 1UL : size);
 469     }
 470   UnlockSemaphoreInfo(memory_semaphore);
 471 #endif
 472   return(memory);
 473 }
 474 \f
 475 /*
 476 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 477 %                                                                             %
 478 %                                                                             %
 479 %                                                                             %
 480 %   A c q u i r e Q u a n t u m M e m o r y                                   %
 481 %                                                                             %
 482 %                                                                             %
 483 %                                                                             %
 484 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 485 %
 486 %  AcquireQuantumMemory() returns a pointer to a block of memory at least
 487 %  count * quantum bytes suitably aligned for any use.
 488 %
 489 %  The format of the AcquireQuantumMemory method is:
 490 %
 491 %      void *AcquireQuantumMemory(const size_t count,const size_t quantum)
 492 %
 493 %  A description of each parameter follows:
 494 %
 495 %    o count: the number of quantum elements to allocate.
 496 %
 497 %    o quantum: the number of bytes in each quantum.
 498 %
 499 */
 500 MagickExport void *AcquireQuantumMemory(const size_t count,const size_t quantum)
 501 {
 502   size_t
 503     size;
 504
 505   size=count*quantum;
 506   if ((count == 0) || (quantum != (size/count)))
 507     {
 508       errno=ENOMEM;
 509       return((void *) NULL);
 510     }
 511   return(AcquireMagickMemory(size));
 512 }
 513 \f
 514 /*
 515 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 516 %                                                                             %
 517 %                                                                             %
 518 %                                                                             %
 519 %   A c q u i r e V i r t u a l M e m o r y                                   %
 520 %                                                                             %
 521 %                                                                             %
 522 %                                                                             %
 523 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 524 %
 525 %  AcquireVirtualMemory() allocates a pointer to a block of memory at least size
 526 %  bytes suitably aligned for any use.
 527 %
 528 %  The format of the AcquireVirtualMemory method is:
 529 %
 530 %      MemoryInfo *AcquireVirtualMemory(const size_t count,const size_t quantum)
 531 %
 532 %  A description of each parameter follows:
 533 %
 534 %    o count: the number of quantum elements to allocate.
 535 %
 536 %    o quantum: the number of bytes in each quantum.
 537 %
 538 */
 539 MagickExport MemoryInfo *AcquireVirtualMemory(const size_t count,
 540   const size_t quantum)
 541 {
 542   MemoryInfo
 543     *memory_info;
 544
 545   size_t
 546     length;
 547
 548   length=count*quantum;
 549   if ((count == 0) || (quantum != (length/count)))
 550     {
 551       errno=ENOMEM;
 552       return((MemoryInfo *) NULL);
 553     }
 554   memory_info=(MemoryInfo *) MagickAssumeAligned(AcquireAlignedMemory(1,
 555     sizeof(*memory_info)));
 556   if (memory_info == (MemoryInfo *) NULL)
 557     ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
 558   (void) ResetMagickMemory(memory_info,0,sizeof(*memory_info));
 559   memory_info->length=length;
 560   memory_info->signature=MagickSignature;
 561   memory_info->blob=AcquireMagickMemory(length);
 562   if (memory_info->blob == NULL)
 563     {
 564       /*
 565         Heap memory failed, try anonymous memory mapping.
 566       */
 567       memory_info->mapped=MagickTrue;
 568       memory_info->blob=MapBlob(-1,IOMode,0,length);
 569     }
 570   if (memory_info->blob == NULL)
 571     {
 572       int
 573         file;
 574
 575       /*
 576         Anonymous memory mapping failed, try file-backed memory mapping.
 577       */
 578       file=AcquireUniqueFileResource(memory_info->filename);
 579       file=open_utf8(memory_info->filename,O_RDWR | O_CREAT | O_BINARY | O_EXCL,
 580         S_MODE);
 581       if (file == -1)
 582         file=open_utf8(memory_info->filename,O_RDWR | O_BINARY,S_MODE);
 583       if (file != -1)
 584         {
 585           if ((lseek(file,length-1,SEEK_SET) >= 0) && (write(file,"",1) == 1))
 586             memory_info->blob=MapBlob(file,IOMode,0,length);
 587           (void) close(file);
 588         }
 589     }
 590   if (memory_info->blob == NULL)
 591     return(RelinquishVirtualMemory(memory_info));
 592   return(memory_info);
 593 }
 594 \f
 595 /*
 596 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 597 %                                                                             %
 598 %                                                                             %
 599 %                                                                             %
 600 %   C o p y M a g i c k M e m o r y                                           %
 601 %                                                                             %
 602 %                                                                             %
 603 %                                                                             %
 604 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 605 %
 606 %  CopyMagickMemory() copies size bytes from memory area source to the
 607 %  destination.  Copying between objects that overlap will take place
 608 %  correctly.  It returns destination.
 609 %
 610 %  The format of the CopyMagickMemory method is:
 611 %
 612 %      void *CopyMagickMemory(void *destination,const void *source,
 613 %        const size_t size)
 614 %
 615 %  A description of each parameter follows:
 616 %
 617 %    o destination: the destination.
 618 %
 619 %    o source: the source.
 620 %
 621 %    o size: the size of the memory in bytes to allocate.
 622 %
 623 */
 624 MagickExport void *CopyMagickMemory(void *destination,const void *source,
 625   const size_t size)
 626 {
 627   register const unsigned char
 628     *p;
 629
 630   register unsigned char
 631     *q;
 632
 633   assert(destination != (void *) NULL);
 634   assert(source != (const void *) NULL);
 635   p=(const unsigned char *) source;
 636   q=(unsigned char *) destination;
 637   if (((q+size) < p) || (q > (p+size)))
 638     switch (size)
 639     {
 640       default: return(memcpy(destination,source,size));
 641       case 8: *q++=(*p++);
 642       case 7: *q++=(*p++);
 643       case 6: *q++=(*p++);
 644       case 5: *q++=(*p++);
 645       case 4: *q++=(*p++);
 646       case 3: *q++=(*p++);
 647       case 2: *q++=(*p++);
 648       case 1: *q++=(*p++);
 649       case 0: return(destination);
 650     }
 651   return(memmove(destination,source,size));
 652 }
 653 \f
 654 /*
 655 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 656 %                                                                             %
 657 %                                                                             %
 658 %                                                                             %
 659 +   D e s t r o y M a g i c k M e m o r y                                     %
 660 %                                                                             %
 661 %                                                                             %
 662 %                                                                             %
 663 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 664 %
 665 %  DestroyMagickMemory() deallocates memory associated with the memory manager.
 666 %
 667 %  The format of the DestroyMagickMemory method is:
 668 %
 669 %      DestroyMagickMemory(void)
 670 %
 671 */
 672 MagickExport void DestroyMagickMemory(void)
 673 {
 674 #if defined(MAGICKCORE_ZERO_CONFIGURATION_SUPPORT)
 675   register ssize_t
 676     i;
 677
 678   if (memory_semaphore == (SemaphoreInfo *) NULL)
 679     AcquireSemaphoreInfo(&memory_semaphore);
 680   LockSemaphoreInfo(memory_semaphore);
 681   UnlockSemaphoreInfo(memory_semaphore);
 682   for (i=0; i < (ssize_t) memory_pool.number_segments; i++)
 683     if (memory_pool.segments[i]->mapped == MagickFalse)
 684       memory_methods.destroy_memory_handler(
 685         memory_pool.segments[i]->allocation);
 686     else
 687       (void) UnmapBlob(memory_pool.segments[i]->allocation,
 688         memory_pool.segments[i]->length);
 689   free_segments=(DataSegmentInfo *) NULL;
 690   (void) ResetMagickMemory(&memory_pool,0,sizeof(memory_pool));
 691   DestroySemaphoreInfo(&memory_semaphore);
 692 #endif
 693 }
 694 \f
 695 #if defined(MAGICKCORE_ZERO_CONFIGURATION_SUPPORT)
 696 /*
 697 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 698 %                                                                             %
 699 %                                                                             %
 700 %                                                                             %
 701 +   E x p a n d H e a p                                                       %
 702 %                                                                             %
 703 %                                                                             %
 704 %                                                                             %
 705 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 706 %
 707 %  ExpandHeap() get more memory from the system.  It returns MagickTrue on
 708 %  success otherwise MagickFalse.
 709 %
 710 %  The format of the ExpandHeap method is:
 711 %
 712 %      MagickBooleanType ExpandHeap(size_t size)
 713 %
 714 %  A description of each parameter follows:
 715 %
 716 %    o size: the size of the memory in bytes we require.
 717 %
 718 */
 719 static MagickBooleanType ExpandHeap(size_t size)
 720 {
 721   DataSegmentInfo
 722     *segment_info;
 723
 724   MagickBooleanType
 725     mapped;
 726
 727   register ssize_t
 728     i;
 729
 730   register void
 731     *block;
 732
 733   size_t
 734     blocksize;
 735
 736   void
 737     *segment;
 738
 739   blocksize=((size+12*sizeof(size_t))+SegmentSize-1) & -SegmentSize;
 740   assert(memory_pool.number_segments < MaxSegments);
 741   segment=MapBlob(-1,IOMode,0,blocksize);
 742   mapped=segment != (void *) NULL ? MagickTrue : MagickFalse;
 743   if (segment == (void *) NULL)
 744     segment=(void *) memory_methods.acquire_memory_handler(blocksize);
 745   if (segment == (void *) NULL)
 746     return(MagickFalse);
 747   segment_info=(DataSegmentInfo *) free_segments;
 748   free_segments=segment_info->next;
 749   segment_info->mapped=mapped;
 750   segment_info->length=blocksize;
 751   segment_info->allocation=segment;
 752   segment_info->bound=(char *) segment+blocksize;
 753   i=(ssize_t) memory_pool.number_segments-1;
 754   for ( ; (i >= 0) && (memory_pool.segments[i]->allocation > segment); i--)
 755     memory_pool.segments[i+1]=memory_pool.segments[i];
 756   memory_pool.segments[i+1]=segment_info;
 757   memory_pool.number_segments++;
 758   size=blocksize-12*sizeof(size_t);
 759   block=(char *) segment_info->allocation+4*sizeof(size_t);
 760   *BlockHeader(block)=size | PreviousBlockBit;
 761   *BlockFooter(block,size)=size;
 762   InsertFreeBlock(block,AllocationPolicy(size));
 763   block=NextBlock(block);
 764   assert(block < segment_info->bound);
 765   *BlockHeader(block)=2*sizeof(size_t);
 766   *BlockHeader(NextBlock(block))=PreviousBlockBit;
 767   return(MagickTrue);
 768 }
 769 #endif
 770 \f
 771 /*
 772 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 773 %                                                                             %
 774 %                                                                             %
 775 %                                                                             %
 776 %   G e t M a g i c k M e m o r y M e t h o d s                               %
 777 %                                                                             %
 778 %                                                                             %
 779 %                                                                             %
 780 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 781 %
 782 %  GetMagickMemoryMethods() gets the methods to acquire, resize, and destroy
 783 %  memory.
 784 %
 785 %  The format of the GetMagickMemoryMethods() method is:
 786 %
 787 %      void GetMagickMemoryMethods(AcquireMemoryHandler *acquire_memory_handler,
 788 %        ResizeMemoryHandler *resize_memory_handler,
 789 %        DestroyMemoryHandler *destroy_memory_handler)
 790 %
 791 %  A description of each parameter follows:
 792 %
 793 %    o acquire_memory_handler: method to acquire memory (e.g. malloc).
 794 %
 795 %    o resize_memory_handler: method to resize memory (e.g. realloc).
 796 %
 797 %    o destroy_memory_handler: method to destroy memory (e.g. free).
 798 %
 799 */
 800 MagickExport void GetMagickMemoryMethods(
 801   AcquireMemoryHandler *acquire_memory_handler,
 802   ResizeMemoryHandler *resize_memory_handler,
 803   DestroyMemoryHandler *destroy_memory_handler)
 804 {
 805   assert(acquire_memory_handler != (AcquireMemoryHandler *) NULL);
 806   assert(resize_memory_handler != (ResizeMemoryHandler *) NULL);
 807   assert(destroy_memory_handler != (DestroyMemoryHandler *) NULL);
 808   *acquire_memory_handler=memory_methods.acquire_memory_handler;
 809   *resize_memory_handler=memory_methods.resize_memory_handler;
 810   *destroy_memory_handler=memory_methods.destroy_memory_handler;
 811 }
 812 \f
 813 /*
 814 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 815 %                                                                             %
 816 %                                                                             %
 817 %                                                                             %
 818 %   G e t V i r t u a l M e m o r y B l o b                                   %
 819 %                                                                             %
 820 %                                                                             %
 821 %                                                                             %
 822 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 823 %
 824 %  GetVirtualMemoryBlob() returns the virtual memory blob associated with the
 825 %  specified MemoryInfo structure.
 826 %
 827 %  The format of the GetVirtualMemoryBlob method is:
 828 %
 829 %      void *GetVirtualMemoryBlob(const MemoryInfo *memory_info)
 830 %
 831 %  A description of each parameter follows:
 832 %
 833 %    o memory_info: The MemoryInfo structure.
 834 */
 835 MagickExport void *GetVirtualMemoryBlob(const MemoryInfo *memory_info)
 836 {
 837   assert(memory_info != (const MemoryInfo *) NULL);
 838   assert(memory_info->signature == MagickSignature);
 839   return(memory_info->blob);
 840 }
 841 \f
 842 /*
 843 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 844 %                                                                             %
 845 %                                                                             %
 846 %                                                                             %
 847 %   R e l i n q u i s h A l i g n e d M e m o r y                             %
 848 %                                                                             %
 849 %                                                                             %
 850 %                                                                             %
 851 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 852 %
 853 %  RelinquishAlignedMemory() frees memory acquired with AcquireAlignedMemory()
 854 %  or reuse.
 855 %
 856 %  The format of the RelinquishAlignedMemory method is:
 857 %
 858 %      void *RelinquishAlignedMemory(void *memory)
 859 %
 860 %  A description of each parameter follows:
 861 %
 862 %    o memory: A pointer to a block of memory to free for reuse.
 863 %
 864 */
 865 MagickExport void *RelinquishAlignedMemory(void *memory)
 866 {
 867   if (memory == (void *) NULL)
 868     return((void *) NULL);
 869 #if defined(MAGICKCORE_HAVE_POSIX_MEMALIGN)
 870   free(memory);
 871 #elif defined(MAGICKCORE_HAVE__ALIGNED_MALLOC)
 872   _aligned_free(memory);
 873 #else
 874   free(*((void **) memory-1));
 875 #endif
 876   return(NULL);
 877 }
 878 \f
 879 /*
 880 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 881 %                                                                             %
 882 %                                                                             %
 883 %                                                                             %
 884 %   R e l i n q u i s h M a g i c k M e m o r y                               %
 885 %                                                                             %
 886 %                                                                             %
 887 %                                                                             %
 888 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 889 %
 890 %  RelinquishMagickMemory() frees memory acquired with AcquireMagickMemory()
 891 %  or AcquireQuantumMemory() for reuse.
 892 %
 893 %  The format of the RelinquishMagickMemory method is:
 894 %
 895 %      void *RelinquishMagickMemory(void *memory)
 896 %
 897 %  A description of each parameter follows:
 898 %
 899 %    o memory: A pointer to a block of memory to free for reuse.
 900 %
 901 */
 902 MagickExport void *RelinquishMagickMemory(void *memory)
 903 {
 904   if (memory == (void *) NULL)
 905     return((void *) NULL);
 906 #if !defined(MAGICKCORE_ZERO_CONFIGURATION_SUPPORT)
 907   memory_methods.destroy_memory_handler(memory);
 908 #else
 909   LockSemaphoreInfo(memory_semaphore);
 910   assert((SizeOfBlock(memory) % (4*sizeof(size_t))) == 0);
 911   assert((*BlockHeader(NextBlock(memory)) & PreviousBlockBit) != 0);
 912   if ((*BlockHeader(memory) & PreviousBlockBit) == 0)
 913     {
 914       void
 915         *previous;
 916
 917       /*
 918         Coalesce with previous adjacent block.
 919       */
 920       previous=PreviousBlock(memory);
 921       RemoveFreeBlock(previous,AllocationPolicy(SizeOfBlock(previous)));
 922       *BlockHeader(previous)=(SizeOfBlock(previous)+SizeOfBlock(memory)) |
 923         (*BlockHeader(previous) & ~SizeMask);
 924       memory=previous;
 925     }
 926   if ((*BlockHeader(NextBlock(NextBlock(memory))) & PreviousBlockBit) == 0)
 927     {
 928       void
 929         *next;
 930
 931       /*
 932         Coalesce with next adjacent block.
 933       */
 934       next=NextBlock(memory);
 935       RemoveFreeBlock(next,AllocationPolicy(SizeOfBlock(next)));
 936       *BlockHeader(memory)=(SizeOfBlock(memory)+SizeOfBlock(next)) |
 937         (*BlockHeader(memory) & ~SizeMask);
 938     }
 939   *BlockFooter(memory,SizeOfBlock(memory))=SizeOfBlock(memory);
 940   *BlockHeader(NextBlock(memory))&=(~PreviousBlockBit);
 941   InsertFreeBlock(memory,AllocationPolicy(SizeOfBlock(memory)));
 942   UnlockSemaphoreInfo(memory_semaphore);
 943 #endif
 944   return((void *) NULL);
 945 }
 946 \f
 947 /*
 948 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 949 %                                                                             %
 950 %                                                                             %
 951 %                                                                             %
 952 %   R e l i n q u i s h V i r t u a l M e m o r y                             %
 953 %                                                                             %
 954 %                                                                             %
 955 %                                                                             %
 956 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 957 %
 958 %  RelinquishVirtualMemory() frees memory acquired with AcquireVirtualMemory().
 959 %
 960 %  The format of the RelinquishVirtualMemory method is:
 961 %
 962 %      MemoryInfo *RelinquishVirtualMemory(MemoryInfo *memory_info)
 963 %
 964 %  A description of each parameter follows:
 965 %
 966 %    o memory_info: A pointer to a block of memory to free for reuse.
 967 %
 968 */
 969 MagickExport MemoryInfo *RelinquishVirtualMemory(MemoryInfo *memory_info)
 970 {
 971   assert(memory_info != (MemoryInfo *) NULL);
 972   assert(memory_info->signature == MagickSignature);
 973   if (memory_info->blob != (void *) NULL)
 974     {
 975       if (memory_info->mapped == MagickFalse)
 976         memory_info->blob=RelinquishMagickMemory(memory_info->blob);
 977       else
 978         {
 979           (void) UnmapBlob(memory_info->blob,memory_info->length);
 980           memory_info->blob=NULL;
 981           if (*memory_info->filename != '\0')
 982             (void) RelinquishUniqueFileResource(memory_info->filename);
 983         }
 984     }
 985   memory_info->signature=(~MagickSignature);
 986   memory_info=(MemoryInfo *) RelinquishAlignedMemory(memory_info);
 987   return(memory_info);
 988 }
 989 \f
 990 /*
 991 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 992 %                                                                             %
 993 %                                                                             %
 994 %                                                                             %
 995 %   R e s e t M a g i c k M e m o r y                                         %
 996 %                                                                             %
 997 %                                                                             %
 998 %                                                                             %
 999 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1000 %
1001 %  ResetMagickMemory() fills the first size bytes of the memory area pointed to
1002 %  by memory with the constant byte c.
1003 %
1004 %  The format of the ResetMagickMemory method is:
1005 %
1006 %      void *ResetMagickMemory(void *memory,int byte,const size_t size)
1007 %
1008 %  A description of each parameter follows:
1009 %
1010 %    o memory: a pointer to a memory allocation.
1011 %
1012 %    o byte: set the memory to this value.
1013 %
1014 %    o size: size of the memory to reset.
1015 %
1016 */
1017 MagickExport void *ResetMagickMemory(void *memory,int byte,const size_t size)
1018 {
1019   assert(memory != (void *) NULL);
1020   return(memset(memory,byte,size));
1021 }
1022 \f
1023 /*
1024 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1025 %                                                                             %
1026 %                                                                             %
1027 %                                                                             %
1028 %   R e s i z e M a g i c k M e m o r y                                       %
1029 %                                                                             %
1030 %                                                                             %
1031 %                                                                             %
1032 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1033 %
1034 %  ResizeMagickMemory() changes the size of the memory and returns a pointer to
1035 %  the (possibly moved) block.  The contents will be unchanged up to the
1036 %  lesser of the new and old sizes.
1037 %
1038 %  The format of the ResizeMagickMemory method is:
1039 %
1040 %      void *ResizeMagickMemory(void *memory,const size_t size)
1041 %
1042 %  A description of each parameter follows:
1043 %
1044 %    o memory: A pointer to a memory allocation.
1045 %
1046 %    o size: the new size of the allocated memory.
1047 %
1048 */
1049
1050 #if defined(MAGICKCORE_ZERO_CONFIGURATION_SUPPORT)
1051 static inline void *ResizeBlock(void *block,size_t size)
1052 {
1053   register void
1054     *memory;
1055
1056   if (block == (void *) NULL)
1057     return(AcquireBlock(size));
1058   memory=AcquireBlock(size);
1059   if (memory == (void *) NULL)
1060     return((void *) NULL);
1061   if (size <= (SizeOfBlock(block)-sizeof(size_t)))
1062     (void) memcpy(memory,block,size);
1063   else
1064     (void) memcpy(memory,block,SizeOfBlock(block)-sizeof(size_t));
1065   memory_pool.allocation+=size;
1066   return(memory);
1067 }
1068 #endif
1069
1070 MagickExport void *ResizeMagickMemory(void *memory,const size_t size)
1071 {
1072   register void
1073     *block;
1074
1075   if (memory == (void *) NULL)
1076     return(AcquireMagickMemory(size));
1077 #if !defined(MAGICKCORE_ZERO_CONFIGURATION_SUPPORT)
1078   block=memory_methods.resize_memory_handler(memory,size == 0 ? 1UL : size);
1079   if (block == (void *) NULL)
1080     memory=RelinquishMagickMemory(memory);
1081 #else
1082   LockSemaphoreInfo(memory_semaphore);
1083   block=ResizeBlock(memory,size == 0 ? 1UL : size);
1084   if (block == (void *) NULL)
1085     {
1086       if (ExpandHeap(size == 0 ? 1UL : size) == MagickFalse)
1087         {
1088           UnlockSemaphoreInfo(memory_semaphore);
1089           memory=RelinquishMagickMemory(memory);
1090           ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
1091         }
1092       block=ResizeBlock(memory,size == 0 ? 1UL : size);
1093       assert(block != (void *) NULL);
1094     }
1095   UnlockSemaphoreInfo(memory_semaphore);
1096   memory=RelinquishMagickMemory(memory);
1097 #endif
1098   return(block);
1099 }
1100 \f
1101 /*
1102 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1103 %                                                                             %
1104 %                                                                             %
1105 %                                                                             %
1106 %   R e s i z e Q u a n t u m M e m o r y                                     %
1107 %                                                                             %
1108 %                                                                             %
1109 %                                                                             %
1110 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1111 %
1112 %  ResizeQuantumMemory() changes the size of the memory and returns a pointer
1113 %  to the (possibly moved) block.  The contents will be unchanged up to the
1114 %  lesser of the new and old sizes.
1115 %
1116 %  The format of the ResizeQuantumMemory method is:
1117 %
1118 %      void *ResizeQuantumMemory(void *memory,const size_t count,
1119 %        const size_t quantum)
1120 %
1121 %  A description of each parameter follows:
1122 %
1123 %    o memory: A pointer to a memory allocation.
1124 %
1125 %    o count: the number of quantum elements to allocate.
1126 %
1127 %    o quantum: the number of bytes in each quantum.
1128 %
1129 */
1130 MagickExport void *ResizeQuantumMemory(void *memory,const size_t count,
1131   const size_t quantum)
1132 {
1133   size_t
1134     size;
1135
1136   size=count*quantum;
1137   if ((count == 0) || (quantum != (size/count)))
1138     {
1139       memory=RelinquishMagickMemory(memory);
1140       errno=ENOMEM;
1141       return((void *) NULL);
1142     }
1143   return(ResizeMagickMemory(memory,size));
1144 }
1145 \f
1146 /*
1147 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1148 %                                                                             %
1149 %                                                                             %
1150 %                                                                             %
1151 %   S e t M a g i c k M e m o r y M e t h o d s                               %
1152 %                                                                             %
1153 %                                                                             %
1154 %                                                                             %
1155 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1156 %
1157 %  SetMagickMemoryMethods() sets the methods to acquire, resize, and destroy
1158 %  memory. Your custom memory methods must be set prior to the
1159 %  MagickCoreGenesis() method.
1160 %
1161 %  The format of the SetMagickMemoryMethods() method is:
1162 %
1163 %      SetMagickMemoryMethods(AcquireMemoryHandler acquire_memory_handler,
1164 %        ResizeMemoryHandler resize_memory_handler,
1165 %        DestroyMemoryHandler destroy_memory_handler)
1166 %
1167 %  A description of each parameter follows:
1168 %
1169 %    o acquire_memory_handler: method to acquire memory (e.g. malloc).
1170 %
1171 %    o resize_memory_handler: method to resize memory (e.g. realloc).
1172 %
1173 %    o destroy_memory_handler: method to destroy memory (e.g. free).
1174 %
1175 */
1176 MagickExport void SetMagickMemoryMethods(
1177   AcquireMemoryHandler acquire_memory_handler,
1178   ResizeMemoryHandler resize_memory_handler,
1179   DestroyMemoryHandler destroy_memory_handler)
1180 {
1181   /*
1182     Set memory methods.
1183   */
1184   if (acquire_memory_handler != (AcquireMemoryHandler) NULL)
1185     memory_methods.acquire_memory_handler=acquire_memory_handler;
1186   if (resize_memory_handler != (ResizeMemoryHandler) NULL)
1187     memory_methods.resize_memory_handler=resize_memory_handler;
1188   if (destroy_memory_handler != (DestroyMemoryHandler) NULL)
1189     memory_methods.destroy_memory_handler=destroy_memory_handler;
1190 }