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/* ---------- To make a malloc.h, start cutting here ------------ */
2
 
3
/*
4
  A version of malloc/free/realloc written by Doug Lea and released to the
5
  public domain.  Send questions/comments/complaints/performance data
6
  to dl@cs.oswego.edu
7
 
8
* VERSION 2.6.6  Sun Mar  5 19:10:03 2000  Doug Lea  (dl at gee)
9
 
10
   Note: There may be an updated version of this malloc obtainable at
11
           ftp://g.oswego.edu/pub/misc/malloc.c
12
         Check before installing!
13
 
14
* Why use this malloc?
15
 
16
  This is not the fastest, most space-conserving, most portable, or
17
  most tunable malloc ever written. However it is among the fastest
18
  while also being among the most space-conserving, portable and tunable.
19
  Consistent balance across these factors results in a good general-purpose
20
  allocator. For a high-level description, see
21
     http://g.oswego.edu/dl/html/malloc.html
22
 
23
* Synopsis of public routines
24
 
25
  (Much fuller descriptions are contained in the program documentation below.)
26
 
27
  malloc(size_t n);
28
     Return a pointer to a newly allocated chunk of at least n bytes, or null
29
     if no space is available.
30
  free(Void_t* p);
31
     Release the chunk of memory pointed to by p, or no effect if p is null.
32
  realloc(Void_t* p, size_t n);
33
     Return a pointer to a chunk of size n that contains the same data
34
     as does chunk p up to the minimum of (n, p's size) bytes, or null
35
     if no space is available. The returned pointer may or may not be
36
     the same as p. If p is null, equivalent to malloc.  Unless the
37
     #define REALLOC_ZERO_BYTES_FREES below is set, realloc with a
38
     size argument of zero (re)allocates a minimum-sized chunk.
39
  memalign(size_t alignment, size_t n);
40
     Return a pointer to a newly allocated chunk of n bytes, aligned
41
     in accord with the alignment argument, which must be a power of
42
     two.
43
  valloc(size_t n);
44
     Equivalent to memalign(pagesize, n), where pagesize is the page
45
     size of the system (or as near to this as can be figured out from
46
     all the includes/defines below.)
47
  pvalloc(size_t n);
48
     Equivalent to valloc(minimum-page-that-holds(n)), that is,
49
     round up n to nearest pagesize.
50
  calloc(size_t unit, size_t quantity);
51
     Returns a pointer to quantity * unit bytes, with all locations
52
     set to zero.
53
  cfree(Void_t* p);
54
     Equivalent to free(p).
55
  malloc_trim(size_t pad);
56
     Release all but pad bytes of freed top-most memory back
57
     to the system. Return 1 if successful, else 0.
58
  malloc_usable_size(Void_t* p);
59
     Report the number usable allocated bytes associated with allocated
60
     chunk p. This may or may not report more bytes than were requested,
61
     due to alignment and minimum size constraints.
62
  malloc_stats();
63
     Prints brief summary statistics on stderr.
64
  mallinfo()
65
     Returns (by copy) a struct containing various summary statistics.
66
  mallopt(int parameter_number, int parameter_value)
67
     Changes one of the tunable parameters described below. Returns
68
     1 if successful in changing the parameter, else 0.
69
 
70
* Vital statistics:
71
 
72
  Alignment:                            8-byte
73
       8 byte alignment is currently hardwired into the design.  This
74
       seems to suffice for all current machines and C compilers.
75
 
76
  Assumed pointer representation:       4 or 8 bytes
77
       Code for 8-byte pointers is untested by me but has worked
78
       reliably by Wolfram Gloger, who contributed most of the
79
       changes supporting this.
80
 
81
  Assumed size_t  representation:       4 or 8 bytes
82
       Note that size_t is allowed to be 4 bytes even if pointers are 8.
83
 
84
  Minimum overhead per allocated chunk: 4 or 8 bytes
85
       Each malloced chunk has a hidden overhead of 4 bytes holding size
86
       and status information.
87
 
88
  Minimum allocated size: 4-byte ptrs:  16 bytes    (including 4 overhead)
89
                          8-byte ptrs:  24/32 bytes (including, 4/8 overhead)
90
 
91
       When a chunk is freed, 12 (for 4byte ptrs) or 20 (for 8 byte
92
       ptrs but 4 byte size) or 24 (for 8/8) additional bytes are
93
       needed; 4 (8) for a trailing size field
94
       and 8 (16) bytes for free list pointers. Thus, the minimum
95
       allocatable size is 16/24/32 bytes.
96
 
97
       Even a request for zero bytes (i.e., malloc(0)) returns a
98
       pointer to something of the minimum allocatable size.
99
 
100
  Maximum allocated size: 4-byte size_t: 2^31 -  8 bytes
101
                          8-byte size_t: 2^63 - 16 bytes
102
 
103
       It is assumed that (possibly signed) size_t bit values suffice to
104
       represent chunk sizes. `Possibly signed' is due to the fact
105
       that `size_t' may be defined on a system as either a signed or
106
       an unsigned type. To be conservative, values that would appear
107
       as negative numbers are avoided.
108
       Requests for sizes with a negative sign bit when the request
109
       size is treaded as a long will return null.
110
 
111
  Maximum overhead wastage per allocated chunk: normally 15 bytes
112
 
113
       Alignnment demands, plus the minimum allocatable size restriction
114
       make the normal worst-case wastage 15 bytes (i.e., up to 15
115
       more bytes will be allocated than were requested in malloc), with
116
       two exceptions:
117
         1. Because requests for zero bytes allocate non-zero space,
118
            the worst case wastage for a request of zero bytes is 24 bytes.
119
         2. For requests >= mmap_threshold that are serviced via
120
            mmap(), the worst case wastage is 8 bytes plus the remainder
121
            from a system page (the minimal mmap unit); typically 4096 bytes.
122
 
123
* Limitations
124
 
125
    Here are some features that are NOT currently supported
126
 
127
    * No user-definable hooks for callbacks and the like.
128
    * No automated mechanism for fully checking that all accesses
129
      to malloced memory stay within their bounds.
130
    * No support for compaction.
131
 
132
* Synopsis of compile-time options:
133
 
134
    People have reported using previous versions of this malloc on all
135
    versions of Unix, sometimes by tweaking some of the defines
136
    below. It has been tested most extensively on Solaris and
137
    Linux. It is also reported to work on WIN32 platforms.
138
    People have also reported adapting this malloc for use in
139
    stand-alone embedded systems.
140
 
141
    The implementation is in straight, hand-tuned ANSI C.  Among other
142
    consequences, it uses a lot of macros.  Because of this, to be at
143
    all usable, this code should be compiled using an optimizing compiler
144
    (for example gcc -O2) that can simplify expressions and control
145
    paths.
146
 
147
  __STD_C                  (default: derived from C compiler defines)
148
     Nonzero if using ANSI-standard C compiler, a C++ compiler, or
149
     a C compiler sufficiently close to ANSI to get away with it.
150
  DEBUG                    (default: NOT defined)
151
     Define to enable debugging. Adds fairly extensive assertion-based
152
     checking to help track down memory errors, but noticeably slows down
153
     execution.
154
  SEPARATE_OBJECTS         (default: NOT defined)
155
     Define this to compile into separate .o files.  You must then
156
     compile malloc.c several times, defining a DEFINE_* macro each
157
     time.  The list of DEFINE_* macros appears below.
158
  MALLOC_LOCK              (default: NOT defined)
159
  MALLOC_UNLOCK            (default: NOT defined)
160
     Define these to C expressions which are run to lock and unlock
161
     the malloc data structures.  Calls may be nested; that is,
162
     MALLOC_LOCK may be called more than once before the corresponding
163
     MALLOC_UNLOCK calls.  MALLOC_LOCK must avoid waiting for a lock
164
     that it already holds.
165
  MALLOC_ALIGNMENT          (default: NOT defined)
166
     Define this to 16 if you need 16 byte alignment instead of 8 byte alignment
167
     which is the normal default.
168
  SIZE_T_SMALLER_THAN_LONG (default: NOT defined)
169
     Define this when the platform you are compiling has sizeof(long) > sizeof(size_t).
170
     The option causes some extra code to be generated to handle operations
171
     that use size_t operands and have long results.
172
  REALLOC_ZERO_BYTES_FREES (default: NOT defined)
173
     Define this if you think that realloc(p, 0) should be equivalent
174
     to free(p). Otherwise, since malloc returns a unique pointer for
175
     malloc(0), so does realloc(p, 0).
176
  HAVE_MEMCPY               (default: defined)
177
     Define if you are not otherwise using ANSI STD C, but still
178
     have memcpy and memset in your C library and want to use them.
179
     Otherwise, simple internal versions are supplied.
180
  USE_MEMCPY               (default: 1 if HAVE_MEMCPY is defined, 0 otherwise)
181
     Define as 1 if you want the C library versions of memset and
182
     memcpy called in realloc and calloc (otherwise macro versions are used).
183
     At least on some platforms, the simple macro versions usually
184
     outperform libc versions.
185
  HAVE_MMAP                 (default: defined as 1)
186
     Define to non-zero to optionally make malloc() use mmap() to
187
     allocate very large blocks.
188
  HAVE_MREMAP                 (default: defined as 0 unless Linux libc set)
189
     Define to non-zero to optionally make realloc() use mremap() to
190
     reallocate very large blocks.
191
  malloc_getpagesize        (default: derived from system #includes)
192
     Either a constant or routine call returning the system page size.
193
  HAVE_USR_INCLUDE_MALLOC_H (default: NOT defined)
194
     Optionally define if you are on a system with a /usr/include/malloc.h
195
     that declares struct mallinfo. It is not at all necessary to
196
     define this even if you do, but will ensure consistency.
197
  INTERNAL_SIZE_T           (default: size_t)
198
     Define to a 32-bit type (probably `unsigned int') if you are on a
199
     64-bit machine, yet do not want or need to allow malloc requests of
200
     greater than 2^31 to be handled. This saves space, especially for
201
     very small chunks.
202
  INTERNAL_LINUX_C_LIB      (default: NOT defined)
203
     Defined only when compiled as part of Linux libc.
204
     Also note that there is some odd internal name-mangling via defines
205
     (for example, internally, `malloc' is named `mALLOc') needed
206
     when compiling in this case. These look funny but don't otherwise
207
     affect anything.
208
  INTERNAL_NEWLIB           (default: NOT defined)
209
     Defined only when compiled as part of the Cygnus newlib
210
     distribution.
211
  WIN32                     (default: undefined)
212
     Define this on MS win (95, nt) platforms to compile in sbrk emulation.
213
  LACKS_UNISTD_H            (default: undefined if not WIN32)
214
     Define this if your system does not have a <unistd.h>.
215
  LACKS_SYS_PARAM_H         (default: undefined if not WIN32)
216
     Define this if your system does not have a <sys/param.h>.
217
  MORECORE                  (default: sbrk)
218
     The name of the routine to call to obtain more memory from the system.
219
  MORECORE_FAILURE          (default: -1)
220
     The value returned upon failure of MORECORE.
221
  MORECORE_CLEARS           (default 1)
222
     True (1) if the routine mapped to MORECORE zeroes out memory (which
223
     holds for sbrk).
224
  DEFAULT_TRIM_THRESHOLD
225
  DEFAULT_TOP_PAD
226
  DEFAULT_MMAP_THRESHOLD
227
  DEFAULT_MMAP_MAX
228
     Default values of tunable parameters (described in detail below)
229
     controlling interaction with host system routines (sbrk, mmap, etc).
230
     These values may also be changed dynamically via mallopt(). The
231
     preset defaults are those that give best performance for typical
232
     programs/systems.
233
  USE_DL_PREFIX             (default: undefined)
234
     Prefix all public routines with the string 'dl'.  Useful to
235
     quickly avoid procedure declaration conflicts and linker symbol
236
     conflicts with existing memory allocation routines.
237
 
238
 
239
*/
240
 
241
 
242
 
243
 
244
/* Preliminaries */
245
 
246
#ifndef __STD_C
247
#ifdef __STDC__
248
#define __STD_C     1
249
#else
250
#if __cplusplus
251
#define __STD_C     1
252
#else
253
#define __STD_C     0
254
#endif /*__cplusplus*/
255
#endif /*__STDC__*/
256
#endif /*__STD_C*/
257
 
258
#ifndef Void_t
259
#if (__STD_C || defined(WIN32))
260
#define Void_t      void
261
#else
262
#define Void_t      char
263
#endif
264
#endif /*Void_t*/
265
 
266
#if __STD_C
267
#include <stddef.h>   /* for size_t */
268
#else
269
#include <sys/types.h>
270
#endif
271
 
272
#ifdef __cplusplus
273
extern "C" {
274
#endif
275
 
276
#include <stdio.h>    /* needed for malloc_stats */
277
 
278
 
279
/*
280
  Compile-time options
281
*/
282
 
283
 
284
/*
285
 
286
  Special defines for Cygnus newlib distribution.
287
 
288
 */
289
 
290
#ifdef INTERNAL_NEWLIB
291
 
292
#include <sys/config.h>
293
 
294
/*
295
  In newlib, all the publically visible routines take a reentrancy
296
  pointer.  We don't currently do anything much with it, but we do
297
  pass it to the lock routine.
298
 */
299
 
300
#include <reent.h>
301
 
302
#define POINTER_UINT unsigned _POINTER_INT
303
#define SEPARATE_OBJECTS
304
#define HAVE_MMAP 0
305
#define MORECORE(size) _sbrk_r(reent_ptr, (size))
306
#define MORECORE_CLEARS 0
307
#define MALLOC_LOCK __malloc_lock(reent_ptr)
308
#define MALLOC_UNLOCK __malloc_unlock(reent_ptr)
309
 
310
#ifndef _WIN32
311
#ifdef SMALL_MEMORY
312
#define malloc_getpagesize (128)
313
#else
314
#define malloc_getpagesize (4096)
315
#endif
316
#endif
317
 
318
#if __STD_C
319
extern void __malloc_lock(struct _reent *);
320
extern void __malloc_unlock(struct _reent *);
321
#else
322
extern void __malloc_lock();
323
extern void __malloc_unlock();
324
#endif
325
 
326
#if __STD_C
327
#define RARG struct _reent *reent_ptr,
328
#define RONEARG struct _reent *reent_ptr
329
#else
330
#define RARG reent_ptr
331
#define RONEARG reent_ptr
332
#define RDECL struct _reent *reent_ptr;
333
#endif
334
 
335
#define RCALL reent_ptr,
336
#define RONECALL reent_ptr
337
 
338
#else /* ! INTERNAL_NEWLIB */
339
 
340
#define POINTER_UINT unsigned long
341
#define RARG
342
#define RONEARG
343
#define RDECL
344
#define RCALL
345
#define RONECALL
346
 
347
#endif /* ! INTERNAL_NEWLIB */
348
 
349
/*
350
    Debugging:
351
 
352
    Because freed chunks may be overwritten with link fields, this
353
    malloc will often die when freed memory is overwritten by user
354
    programs.  This can be very effective (albeit in an annoying way)
355
    in helping track down dangling pointers.
356
 
357
    If you compile with -DDEBUG, a number of assertion checks are
358
    enabled that will catch more memory errors. You probably won't be
359
    able to make much sense of the actual assertion errors, but they
360
    should help you locate incorrectly overwritten memory.  The
361
    checking is fairly extensive, and will slow down execution
362
    noticeably. Calling malloc_stats or mallinfo with DEBUG set will
363
    attempt to check every non-mmapped allocated and free chunk in the
364
    course of computing the summmaries. (By nature, mmapped regions
365
    cannot be checked very much automatically.)
366
 
367
    Setting DEBUG may also be helpful if you are trying to modify
368
    this code. The assertions in the check routines spell out in more
369
    detail the assumptions and invariants underlying the algorithms.
370
 
371
*/
372
 
373
#if DEBUG 
374
#include <assert.h>
375
#else
376
#define assert(x) ((void)0)
377
#endif
378
 
379
 
380
/*
381
  SEPARATE_OBJECTS should be defined if you want each function to go
382
  into a separate .o file.  You must then compile malloc.c once per
383
  function, defining the appropriate DEFINE_ macro.  See below for the
384
  list of macros.
385
 */
386
 
387
#ifndef SEPARATE_OBJECTS
388
#define DEFINE_MALLOC
389
#define DEFINE_FREE
390
#define DEFINE_REALLOC
391
#define DEFINE_CALLOC
392
#define DEFINE_CFREE
393
#define DEFINE_MEMALIGN
394
#define DEFINE_VALLOC
395
#define DEFINE_PVALLOC
396
#define DEFINE_MALLINFO
397
#define DEFINE_MALLOC_STATS
398
#define DEFINE_MALLOC_USABLE_SIZE
399
#define DEFINE_MALLOPT
400
 
401
#define STATIC static
402
#else
403
#define STATIC
404
#endif
405
 
406
/*
407
   Define MALLOC_LOCK and MALLOC_UNLOCK to C expressions to run to
408
   lock and unlock the malloc data structures.  MALLOC_LOCK may be
409
   called recursively.
410
 */
411
 
412
#ifndef MALLOC_LOCK
413
#define MALLOC_LOCK
414
#endif
415
 
416
#ifndef MALLOC_UNLOCK
417
#define MALLOC_UNLOCK
418
#endif
419
 
420
/*
421
  INTERNAL_SIZE_T is the word-size used for internal bookkeeping
422
  of chunk sizes. On a 64-bit machine, you can reduce malloc
423
  overhead by defining INTERNAL_SIZE_T to be a 32 bit `unsigned int'
424
  at the expense of not being able to handle requests greater than
425
  2^31. This limitation is hardly ever a concern; you are encouraged
426
  to set this. However, the default version is the same as size_t.
427
*/
428
 
429
#ifndef INTERNAL_SIZE_T
430
#define INTERNAL_SIZE_T size_t
431
#endif
432
 
433
/*
434
  Following is needed on implementations whereby long > size_t.
435
  The problem is caused because the code performs subtractions of
436
  size_t values and stores the result in long values.  In the case
437
  where long > size_t and the first value is actually less than
438
  the second value, the resultant value is positive.  For example,
439
  (long)(x - y) where x = 0 and y is 1 ends up being 0x00000000FFFFFFFF
440
  which is 2*31 - 1 instead of 0xFFFFFFFFFFFFFFFF.  This is due to the
441
  fact that assignment from unsigned to signed won't sign extend.
442
*/
443
 
444
#ifdef SIZE_T_SMALLER_THAN_LONG
445
#define long_sub_size_t(x, y) ( (x < y) ? -((long)(y - x)) : (x - y) );
446
#else
447
#define long_sub_size_t(x, y) ( (long)(x - y) )
448
#endif
449
 
450
/*
451
  REALLOC_ZERO_BYTES_FREES should be set if a call to
452
  realloc with zero bytes should be the same as a call to free.
453
  Some people think it should. Otherwise, since this malloc
454
  returns a unique pointer for malloc(0), so does realloc(p, 0).
455
*/
456
 
457
 
458
/*   #define REALLOC_ZERO_BYTES_FREES */
459
 
460
 
461
/*
462
  WIN32 causes an emulation of sbrk to be compiled in
463
  mmap-based options are not currently supported in WIN32.
464
*/
465
 
466
/* #define WIN32 */
467
#ifdef WIN32
468
#define MORECORE wsbrk
469
#define HAVE_MMAP 0
470
 
471
#define LACKS_UNISTD_H
472
#define LACKS_SYS_PARAM_H
473
 
474
/*
475
  Include 'windows.h' to get the necessary declarations for the
476
  Microsoft Visual C++ data structures and routines used in the 'sbrk'
477
  emulation.
478
 
479
  Define WIN32_LEAN_AND_MEAN so that only the essential Microsoft
480
  Visual C++ header files are included.
481
*/
482
#define WIN32_LEAN_AND_MEAN
483
#include <windows.h>
484
#endif
485
 
486
 
487
/*
488
  HAVE_MEMCPY should be defined if you are not otherwise using
489
  ANSI STD C, but still have memcpy and memset in your C library
490
  and want to use them in calloc and realloc. Otherwise simple
491
  macro versions are defined here.
492
 
493
  USE_MEMCPY should be defined as 1 if you actually want to
494
  have memset and memcpy called. People report that the macro
495
  versions are often enough faster than libc versions on many
496
  systems that it is better to use them.
497
 
498
*/
499
 
500
#define HAVE_MEMCPY 
501
 
502
#ifndef USE_MEMCPY
503
#ifdef HAVE_MEMCPY
504
#define USE_MEMCPY 1
505
#else
506
#define USE_MEMCPY 0
507
#endif
508
#endif
509
 
510
#if (__STD_C || defined(HAVE_MEMCPY)) 
511
 
512
#if __STD_C
513
void* memset(void*, int, size_t);
514
void* memcpy(void*, const void*, size_t);
515
#else
516
#ifdef WIN32
517
// On Win32 platforms, 'memset()' and 'memcpy()' are already declared in
518
// 'windows.h'
519
#else
520
Void_t* memset();
521
Void_t* memcpy();
522
#endif
523
#endif
524
#endif
525
 
526
#if USE_MEMCPY
527
 
528
/* The following macros are only invoked with (2n+1)-multiples of
529
   INTERNAL_SIZE_T units, with a positive integer n. This is exploited
530
   for fast inline execution when n is small. */
531
 
532
#define MALLOC_ZERO(charp, nbytes)                                            \
533
do {                                                                          \
534
  INTERNAL_SIZE_T mzsz = (nbytes);                                            \
535
  if(mzsz <= 9*sizeof(mzsz)) {                                                \
536
    INTERNAL_SIZE_T* mz = (INTERNAL_SIZE_T*) (charp);                         \
537
    if(mzsz >= 5*sizeof(mzsz)) {     *mz++ = 0;                               \
538
                                     *mz++ = 0;                               \
539
      if(mzsz >= 7*sizeof(mzsz)) {   *mz++ = 0;                               \
540
                                     *mz++ = 0;                               \
541
        if(mzsz >= 9*sizeof(mzsz)) { *mz++ = 0;                               \
542
                                     *mz++ = 0; }}}                           \
543
                                     *mz++ = 0;                               \
544
                                     *mz++ = 0;                               \
545
                                     *mz   = 0;                               \
546
  } else memset((charp), 0, mzsz);                                            \
547
} while(0)
548
 
549
#define MALLOC_COPY(dest,src,nbytes)                                          \
550
do {                                                                          \
551
  INTERNAL_SIZE_T mcsz = (nbytes);                                            \
552
  if(mcsz <= 9*sizeof(mcsz)) {                                                \
553
    INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) (src);                        \
554
    INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) (dest);                       \
555
    if(mcsz >= 5*sizeof(mcsz)) {     *mcdst++ = *mcsrc++;                     \
556
                                     *mcdst++ = *mcsrc++;                     \
557
      if(mcsz >= 7*sizeof(mcsz)) {   *mcdst++ = *mcsrc++;                     \
558
                                     *mcdst++ = *mcsrc++;                     \
559
        if(mcsz >= 9*sizeof(mcsz)) { *mcdst++ = *mcsrc++;                     \
560
                                     *mcdst++ = *mcsrc++; }}}                 \
561
                                     *mcdst++ = *mcsrc++;                     \
562
                                     *mcdst++ = *mcsrc++;                     \
563
                                     *mcdst   = *mcsrc  ;                     \
564
  } else memcpy(dest, src, mcsz);                                             \
565
} while(0)
566
 
567
#else /* !USE_MEMCPY */
568
 
569
/* Use Duff's device for good zeroing/copying performance. */
570
 
571
#define MALLOC_ZERO(charp, nbytes)                                            \
572
do {                                                                          \
573
  INTERNAL_SIZE_T* mzp = (INTERNAL_SIZE_T*)(charp);                           \
574
  long mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T), mcn;                         \
575
  if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; }             \
576
  switch (mctmp) {                                                            \
577
    case 0: for(;;) { *mzp++ = 0;                                             \
578
    case 7:           *mzp++ = 0;                                             \
579
    case 6:           *mzp++ = 0;                                             \
580
    case 5:           *mzp++ = 0;                                             \
581
    case 4:           *mzp++ = 0;                                             \
582
    case 3:           *mzp++ = 0;                                             \
583
    case 2:           *mzp++ = 0;                                             \
584
    case 1:           *mzp++ = 0; if(mcn <= 0) break; mcn--; }                \
585
  }                                                                           \
586
} while(0)
587
 
588
#define MALLOC_COPY(dest,src,nbytes)                                          \
589
do {                                                                          \
590
  INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) src;                            \
591
  INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) dest;                           \
592
  long mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T), mcn;                         \
593
  if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; }             \
594
  switch (mctmp) {                                                            \
595
    case 0: for(;;) { *mcdst++ = *mcsrc++;                                    \
596
    case 7:           *mcdst++ = *mcsrc++;                                    \
597
    case 6:           *mcdst++ = *mcsrc++;                                    \
598
    case 5:           *mcdst++ = *mcsrc++;                                    \
599
    case 4:           *mcdst++ = *mcsrc++;                                    \
600
    case 3:           *mcdst++ = *mcsrc++;                                    \
601
    case 2:           *mcdst++ = *mcsrc++;                                    \
602
    case 1:           *mcdst++ = *mcsrc++; if(mcn <= 0) break; mcn--; }       \
603
  }                                                                           \
604
} while(0)
605
 
606
#endif
607
 
608
 
609
/*
610
  Define HAVE_MMAP to optionally make malloc() use mmap() to
611
  allocate very large blocks.  These will be returned to the
612
  operating system immediately after a free().
613
*/
614
 
615
#ifndef HAVE_MMAP
616
#define HAVE_MMAP 1
617
#endif
618
 
619
/*
620
  Define HAVE_MREMAP to make realloc() use mremap() to re-allocate
621
  large blocks.  This is currently only possible on Linux with
622
  kernel versions newer than 1.3.77.
623
*/
624
 
625
#ifndef HAVE_MREMAP
626
#ifdef INTERNAL_LINUX_C_LIB
627
#define HAVE_MREMAP 1
628
#else
629
#define HAVE_MREMAP 0
630
#endif
631
#endif
632
 
633
#if HAVE_MMAP
634
 
635
#include <unistd.h>
636
#include <fcntl.h>
637
#include <sys/mman.h>
638
 
639
#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
640
#define MAP_ANONYMOUS MAP_ANON
641
#endif
642
 
643
#endif /* HAVE_MMAP */
644
 
645
/*
646
  Access to system page size. To the extent possible, this malloc
647
  manages memory from the system in page-size units.
648
 
649
  The following mechanics for getpagesize were adapted from
650
  bsd/gnu getpagesize.h
651
*/
652
 
653
#ifndef LACKS_UNISTD_H
654
#  include <unistd.h>
655
#endif
656
 
657
#ifndef malloc_getpagesize
658
#  ifdef _SC_PAGESIZE         /* some SVR4 systems omit an underscore */
659
#    ifndef _SC_PAGE_SIZE
660
#      define _SC_PAGE_SIZE _SC_PAGESIZE
661
#    endif
662
#  endif
663
#  ifdef _SC_PAGE_SIZE
664
#    define malloc_getpagesize sysconf(_SC_PAGE_SIZE)
665
#  else
666
#    if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE)
667
       extern size_t getpagesize();
668
#      define malloc_getpagesize getpagesize()
669
#    else
670
#      ifdef WIN32
671
#        define malloc_getpagesize (4096) /* TBD: Use 'GetSystemInfo' instead */
672
#      else
673
#        ifndef LACKS_SYS_PARAM_H
674
#          include <sys/param.h>
675
#        endif
676
#        ifdef EXEC_PAGESIZE
677
#          define malloc_getpagesize EXEC_PAGESIZE
678
#        else
679
#          ifdef NBPG
680
#            ifndef CLSIZE
681
#              define malloc_getpagesize NBPG
682
#            else
683
#              define malloc_getpagesize (NBPG * CLSIZE)
684
#            endif
685
#          else 
686
#            ifdef NBPC
687
#              define malloc_getpagesize NBPC
688
#            else
689
#              ifdef PAGESIZE
690
#                define malloc_getpagesize PAGESIZE
691
#              else
692
#                define malloc_getpagesize (4096) /* just guess */
693
#              endif
694
#            endif
695
#          endif 
696
#        endif
697
#      endif 
698
#    endif
699
#  endif
700
#endif
701
 
702
 
703
 
704
/*
705
 
706
  This version of malloc supports the standard SVID/XPG mallinfo
707
  routine that returns a struct containing the same kind of
708
  information you can get from malloc_stats. It should work on
709
  any SVID/XPG compliant system that has a /usr/include/malloc.h
710
  defining struct mallinfo. (If you'd like to install such a thing
711
  yourself, cut out the preliminary declarations as described above
712
  and below and save them in a malloc.h file. But there's no
713
  compelling reason to bother to do this.)
714
 
715
  The main declaration needed is the mallinfo struct that is returned
716
  (by-copy) by mallinfo().  The SVID/XPG malloinfo struct contains a
717
  bunch of fields, most of which are not even meaningful in this
718
  version of malloc. Some of these fields are are instead filled by
719
  mallinfo() with other numbers that might possibly be of interest.
720
 
721
  HAVE_USR_INCLUDE_MALLOC_H should be set if you have a
722
  /usr/include/malloc.h file that includes a declaration of struct
723
  mallinfo.  If so, it is included; else an SVID2/XPG2 compliant
724
  version is declared below.  These must be precisely the same for
725
  mallinfo() to work.
726
 
727
*/
728
 
729
/* #define HAVE_USR_INCLUDE_MALLOC_H */
730
 
731
#if HAVE_USR_INCLUDE_MALLOC_H
732
#include "/usr/include/malloc.h"
733
#else
734
 
735
/* SVID2/XPG mallinfo structure */
736
 
737
struct mallinfo {
738
  int arena;    /* total space allocated from system */
739
  int ordblks;  /* number of non-inuse chunks */
740
  int smblks;   /* unused -- always zero */
741
  int hblks;    /* number of mmapped regions */
742
  int hblkhd;   /* total space in mmapped regions */
743
  int usmblks;  /* unused -- always zero */
744
  int fsmblks;  /* unused -- always zero */
745
  int uordblks; /* total allocated space */
746
  int fordblks; /* total non-inuse space */
747
  int keepcost; /* top-most, releasable (via malloc_trim) space */
748
};
749
 
750
/* SVID2/XPG mallopt options */
751
 
752
#define M_MXFAST  1    /* UNUSED in this malloc */
753
#define M_NLBLKS  2    /* UNUSED in this malloc */
754
#define M_GRAIN   3    /* UNUSED in this malloc */
755
#define M_KEEP    4    /* UNUSED in this malloc */
756
 
757
#endif
758
 
759
/* mallopt options that actually do something */
760
 
761
#define M_TRIM_THRESHOLD    -1
762
#define M_TOP_PAD           -2
763
#define M_MMAP_THRESHOLD    -3
764
#define M_MMAP_MAX          -4
765
 
766
 
767
 
768
#ifndef DEFAULT_TRIM_THRESHOLD
769
#define DEFAULT_TRIM_THRESHOLD (128L * 1024L)
770
#endif
771
 
772
/*
773
    M_TRIM_THRESHOLD is the maximum amount of unused top-most memory
774
      to keep before releasing via malloc_trim in free().
775
 
776
      Automatic trimming is mainly useful in long-lived programs.
777
      Because trimming via sbrk can be slow on some systems, and can
778
      sometimes be wasteful (in cases where programs immediately
779
      afterward allocate more large chunks) the value should be high
780
      enough so that your overall system performance would improve by
781
      releasing.
782
 
783
      The trim threshold and the mmap control parameters (see below)
784
      can be traded off with one another. Trimming and mmapping are
785
      two different ways of releasing unused memory back to the
786
      system. Between these two, it is often possible to keep
787
      system-level demands of a long-lived program down to a bare
788
      minimum. For example, in one test suite of sessions measuring
789
      the XF86 X server on Linux, using a trim threshold of 128K and a
790
      mmap threshold of 192K led to near-minimal long term resource
791
      consumption.
792
 
793
      If you are using this malloc in a long-lived program, it should
794
      pay to experiment with these values.  As a rough guide, you
795
      might set to a value close to the average size of a process
796
      (program) running on your system.  Releasing this much memory
797
      would allow such a process to run in memory.  Generally, it's
798
      worth it to tune for trimming rather tham memory mapping when a
799
      program undergoes phases where several large chunks are
800
      allocated and released in ways that can reuse each other's
801
      storage, perhaps mixed with phases where there are no such
802
      chunks at all.  And in well-behaved long-lived programs,
803
      controlling release of large blocks via trimming versus mapping
804
      is usually faster.
805
 
806
      However, in most programs, these parameters serve mainly as
807
      protection against the system-level effects of carrying around
808
      massive amounts of unneeded memory. Since frequent calls to
809
      sbrk, mmap, and munmap otherwise degrade performance, the default
810
      parameters are set to relatively high values that serve only as
811
      safeguards.
812
 
813
      The default trim value is high enough to cause trimming only in
814
      fairly extreme (by current memory consumption standards) cases.
815
      It must be greater than page size to have any useful effect.  To
816
      disable trimming completely, you can set to (unsigned long)(-1);
817
 
818
 
819
*/
820
 
821
 
822
#ifndef DEFAULT_TOP_PAD
823
#define DEFAULT_TOP_PAD        (0)
824
#endif
825
 
826
/*
827
    M_TOP_PAD is the amount of extra `padding' space to allocate or
828
      retain whenever sbrk is called. It is used in two ways internally:
829
 
830
      * When sbrk is called to extend the top of the arena to satisfy
831
        a new malloc request, this much padding is added to the sbrk
832
        request.
833
 
834
      * When malloc_trim is called automatically from free(),
835
        it is used as the `pad' argument.
836
 
837
      In both cases, the actual amount of padding is rounded
838
      so that the end of the arena is always a system page boundary.
839
 
840
      The main reason for using padding is to avoid calling sbrk so
841
      often. Having even a small pad greatly reduces the likelihood
842
      that nearly every malloc request during program start-up (or
843
      after trimming) will invoke sbrk, which needlessly wastes
844
      time.
845
 
846
      Automatic rounding-up to page-size units is normally sufficient
847
      to avoid measurable overhead, so the default is 0.  However, in
848
      systems where sbrk is relatively slow, it can pay to increase
849
      this value, at the expense of carrying around more memory than
850
      the program needs.
851
 
852
*/
853
 
854
 
855
#ifndef DEFAULT_MMAP_THRESHOLD
856
#define DEFAULT_MMAP_THRESHOLD (128 * 1024)
857
#endif
858
 
859
/*
860
 
861
    M_MMAP_THRESHOLD is the request size threshold for using mmap()
862
      to service a request. Requests of at least this size that cannot
863
      be allocated using already-existing space will be serviced via mmap.
864
      (If enough normal freed space already exists it is used instead.)
865
 
866
      Using mmap segregates relatively large chunks of memory so that
867
      they can be individually obtained and released from the host
868
      system. A request serviced through mmap is never reused by any
869
      other request (at least not directly; the system may just so
870
      happen to remap successive requests to the same locations).
871
 
872
      Segregating space in this way has the benefit that mmapped space
873
      can ALWAYS be individually released back to the system, which
874
      helps keep the system level memory demands of a long-lived
875
      program low. Mapped memory can never become `locked' between
876
      other chunks, as can happen with normally allocated chunks, which
877
      menas that even trimming via malloc_trim would not release them.
878
 
879
      However, it has the disadvantages that:
880
 
881
         1. The space cannot be reclaimed, consolidated, and then
882
            used to service later requests, as happens with normal chunks.
883
         2. It can lead to more wastage because of mmap page alignment
884
            requirements
885
         3. It causes malloc performance to be more dependent on host
886
            system memory management support routines which may vary in
887
            implementation quality and may impose arbitrary
888
            limitations. Generally, servicing a request via normal
889
            malloc steps is faster than going through a system's mmap.
890
 
891
      All together, these considerations should lead you to use mmap
892
      only for relatively large requests.
893
 
894
 
895
*/
896
 
897
 
898
 
899
#ifndef DEFAULT_MMAP_MAX
900
#if HAVE_MMAP
901
#define DEFAULT_MMAP_MAX       (64)
902
#else
903
#define DEFAULT_MMAP_MAX       (0)
904
#endif
905
#endif
906
 
907
/*
908
    M_MMAP_MAX is the maximum number of requests to simultaneously
909
      service using mmap. This parameter exists because:
910
 
911
         1. Some systems have a limited number of internal tables for
912
            use by mmap.
913
         2. In most systems, overreliance on mmap can degrade overall
914
            performance.
915
         3. If a program allocates many large regions, it is probably
916
            better off using normal sbrk-based allocation routines that
917
            can reclaim and reallocate normal heap memory. Using a
918
            small value allows transition into this mode after the
919
            first few allocations.
920
 
921
      Setting to 0 disables all use of mmap.  If HAVE_MMAP is not set,
922
      the default value is 0, and attempts to set it to non-zero values
923
      in mallopt will fail.
924
*/
925
 
926
 
927
 
928
 
929
/*
930
    USE_DL_PREFIX will prefix all public routines with the string 'dl'.
931
      Useful to quickly avoid procedure declaration conflicts and linker
932
      symbol conflicts with existing memory allocation routines.
933
 
934
*/
935
 
936
/* #define USE_DL_PREFIX */
937
 
938
 
939
 
940
 
941
/*
942
 
943
  Special defines for linux libc
944
 
945
  Except when compiled using these special defines for Linux libc
946
  using weak aliases, this malloc is NOT designed to work in
947
  multithreaded applications.  No semaphores or other concurrency
948
  control are provided to ensure that multiple malloc or free calls
949
  don't run at the same time, which could be disasterous. A single
950
  semaphore could be used across malloc, realloc, and free (which is
951
  essentially the effect of the linux weak alias approach). It would
952
  be hard to obtain finer granularity.
953
 
954
*/
955
 
956
 
957
#ifdef INTERNAL_LINUX_C_LIB
958
 
959
#if __STD_C
960
 
961
Void_t * __default_morecore_init (ptrdiff_t);
962
Void_t *(*__morecore)(ptrdiff_t) = __default_morecore_init;
963
 
964
#else
965
 
966
Void_t * __default_morecore_init ();
967
Void_t *(*__morecore)() = __default_morecore_init;
968
 
969
#endif
970
 
971
#define MORECORE (*__morecore)
972
#define MORECORE_FAILURE 0
973
#define MORECORE_CLEARS 1 
974
 
975
#else /* INTERNAL_LINUX_C_LIB */
976
 
977
#ifndef INTERNAL_NEWLIB
978
#if __STD_C
979
extern Void_t*     sbrk(ptrdiff_t);
980
#else
981
extern Void_t*     sbrk();
982
#endif
983
#endif
984
 
985
#ifndef MORECORE
986
#define MORECORE sbrk
987
#endif
988
 
989
#ifndef MORECORE_FAILURE
990
#define MORECORE_FAILURE -1
991
#endif
992
 
993
#ifndef MORECORE_CLEARS
994
#define MORECORE_CLEARS 1
995
#endif
996
 
997
#endif /* INTERNAL_LINUX_C_LIB */
998
 
999
#if defined(INTERNAL_LINUX_C_LIB) && defined(__ELF__)
1000
 
1001
#define cALLOc          __libc_calloc
1002
#define fREe            __libc_free
1003
#define mALLOc          __libc_malloc
1004
#define mEMALIGn        __libc_memalign
1005
#define rEALLOc         __libc_realloc
1006
#define vALLOc          __libc_valloc
1007
#define pvALLOc         __libc_pvalloc
1008
#define mALLINFo        __libc_mallinfo
1009
#define mALLOPt         __libc_mallopt
1010
 
1011
#pragma weak calloc = __libc_calloc
1012
#pragma weak free = __libc_free
1013
#pragma weak cfree = __libc_free
1014
#pragma weak malloc = __libc_malloc
1015
#pragma weak memalign = __libc_memalign
1016
#pragma weak realloc = __libc_realloc
1017
#pragma weak valloc = __libc_valloc
1018
#pragma weak pvalloc = __libc_pvalloc
1019
#pragma weak mallinfo = __libc_mallinfo
1020
#pragma weak mallopt = __libc_mallopt
1021
 
1022
#else
1023
 
1024
#ifdef INTERNAL_NEWLIB
1025
 
1026
#define cALLOc          _calloc_r
1027
#define fREe            _free_r
1028
#define mALLOc          _malloc_r
1029
#define mEMALIGn        _memalign_r
1030
#define rEALLOc         _realloc_r
1031
#define vALLOc          _valloc_r
1032
#define pvALLOc         _pvalloc_r
1033
#define mALLINFo        _mallinfo_r
1034
#define mALLOPt         _mallopt_r
1035
 
1036
#define malloc_stats                    _malloc_stats_r
1037
#define malloc_trim                     _malloc_trim_r
1038
#define malloc_usable_size              _malloc_usable_size_r
1039
 
1040
#define malloc_update_mallinfo          __malloc_update_mallinfo
1041
 
1042
#define malloc_av_                      __malloc_av_
1043
#define malloc_current_mallinfo         __malloc_current_mallinfo
1044
#define malloc_max_sbrked_mem           __malloc_max_sbrked_mem
1045
#define malloc_max_total_mem            __malloc_max_total_mem
1046
#define malloc_sbrk_base                __malloc_sbrk_base
1047
#define malloc_top_pad                  __malloc_top_pad
1048
#define malloc_trim_threshold           __malloc_trim_threshold
1049
 
1050
#else /* ! INTERNAL_NEWLIB */
1051
 
1052
#ifdef USE_DL_PREFIX
1053
#define cALLOc          dlcalloc
1054
#define fREe            dlfree
1055
#define mALLOc          dlmalloc
1056
#define mEMALIGn        dlmemalign
1057
#define rEALLOc         dlrealloc
1058
#define vALLOc          dlvalloc
1059
#define pvALLOc         dlpvalloc
1060
#define mALLINFo        dlmallinfo
1061
#define mALLOPt         dlmallopt
1062
#else /* USE_DL_PREFIX */
1063
#define cALLOc          calloc
1064
#define fREe            free
1065
#define mALLOc          malloc
1066
#define mEMALIGn        memalign
1067
#define rEALLOc         realloc
1068
#define vALLOc          valloc
1069
#define pvALLOc         pvalloc
1070
#define mALLINFo        mallinfo
1071
#define mALLOPt         mallopt
1072
#endif /* USE_DL_PREFIX */
1073
 
1074
#endif /* ! INTERNAL_NEWLIB */
1075
#endif
1076
 
1077
/* Public routines */
1078
 
1079
#if __STD_C
1080
 
1081
Void_t* mALLOc(RARG size_t);
1082
void    fREe(RARG Void_t*);
1083
Void_t* rEALLOc(RARG Void_t*, size_t);
1084
Void_t* mEMALIGn(RARG size_t, size_t);
1085
Void_t* vALLOc(RARG size_t);
1086
Void_t* pvALLOc(RARG size_t);
1087
Void_t* cALLOc(RARG size_t, size_t);
1088
void    cfree(Void_t*);
1089
int     malloc_trim(RARG size_t);
1090
size_t  malloc_usable_size(RARG Void_t*);
1091
void    malloc_stats(RONEARG);
1092
int     mALLOPt(RARG int, int);
1093
struct mallinfo mALLINFo(RONEARG);
1094
#else
1095
Void_t* mALLOc();
1096
void    fREe();
1097
Void_t* rEALLOc();
1098
Void_t* mEMALIGn();
1099
Void_t* vALLOc();
1100
Void_t* pvALLOc();
1101
Void_t* cALLOc();
1102
void    cfree();
1103
int     malloc_trim();
1104
size_t  malloc_usable_size();
1105
void    malloc_stats();
1106
int     mALLOPt();
1107
struct mallinfo mALLINFo();
1108
#endif
1109
 
1110
 
1111
#ifdef __cplusplus
1112
};  /* end of extern "C" */
1113
#endif
1114
 
1115
/* ---------- To make a malloc.h, end cutting here ------------ */
1116
 
1117
 
1118
/*
1119
  Emulation of sbrk for WIN32
1120
  All code within the ifdef WIN32 is untested by me.
1121
 
1122
  Thanks to Martin Fong and others for supplying this.
1123
*/
1124
 
1125
 
1126
#ifdef WIN32
1127
 
1128
#define AlignPage(add) (((add) + (malloc_getpagesize-1)) & \
1129
~(malloc_getpagesize-1))
1130
#define AlignPage64K(add) (((add) + (0x10000 - 1)) & ~(0x10000 - 1))
1131
 
1132
/* resrve 64MB to insure large contiguous space */
1133
#define RESERVED_SIZE (1024*1024*64)
1134
#define NEXT_SIZE (2048*1024)
1135
#define TOP_MEMORY ((unsigned long)2*1024*1024*1024)
1136
 
1137
struct GmListElement;
1138
typedef struct GmListElement GmListElement;
1139
 
1140
struct GmListElement
1141
{
1142
        GmListElement* next;
1143
        void* base;
1144
};
1145
 
1146
static GmListElement* head = 0;
1147
static unsigned int gNextAddress = 0;
1148
static unsigned int gAddressBase = 0;
1149
static unsigned int gAllocatedSize = 0;
1150
 
1151
static
1152
GmListElement* makeGmListElement (void* bas)
1153
{
1154
        GmListElement* this;
1155
        this = (GmListElement*)(void*)LocalAlloc (0, sizeof (GmListElement));
1156
        assert (this);
1157
        if (this)
1158
        {
1159
                this->base = bas;
1160
                this->next = head;
1161
                head = this;
1162
        }
1163
        return this;
1164
}
1165
 
1166
void gcleanup ()
1167
{
1168
        BOOL rval;
1169
        assert ( (head == NULL) || (head->base == (void*)gAddressBase));
1170
        if (gAddressBase && (gNextAddress - gAddressBase))
1171
        {
1172
                rval = VirtualFree ((void*)gAddressBase,
1173
                                                        gNextAddress - gAddressBase,
1174
                                                        MEM_DECOMMIT);
1175
        assert (rval);
1176
        }
1177
        while (head)
1178
        {
1179
                GmListElement* next = head->next;
1180
                rval = VirtualFree (head->base, 0, MEM_RELEASE);
1181
                assert (rval);
1182
                LocalFree (head);
1183
                head = next;
1184
        }
1185
}
1186
 
1187
static
1188
void* findRegion (void* start_address, unsigned long size)
1189
{
1190
        MEMORY_BASIC_INFORMATION info;
1191
        if (size >= TOP_MEMORY) return NULL;
1192
 
1193
        while ((unsigned long)start_address + size < TOP_MEMORY)
1194
        {
1195
                VirtualQuery (start_address, &info, sizeof (info));
1196
                if ((info.State == MEM_FREE) && (info.RegionSize >= size))
1197
                        return start_address;
1198
                else
1199
                {
1200
                        // Requested region is not available so see if the
1201
                        // next region is available.  Set 'start_address'
1202
                        // to the next region and call 'VirtualQuery()'
1203
                        // again.
1204
 
1205
                        start_address = (char*)info.BaseAddress + info.RegionSize;
1206
 
1207
                        // Make sure we start looking for the next region
1208
                        // on the *next* 64K boundary.  Otherwise, even if
1209
                        // the new region is free according to
1210
                        // 'VirtualQuery()', the subsequent call to
1211
                        // 'VirtualAlloc()' (which follows the call to
1212
                        // this routine in 'wsbrk()') will round *down*
1213
                        // the requested address to a 64K boundary which
1214
                        // we already know is an address in the
1215
                        // unavailable region.  Thus, the subsequent call
1216
                        // to 'VirtualAlloc()' will fail and bring us back
1217
                        // here, causing us to go into an infinite loop.
1218
 
1219
                        start_address =
1220
                                (void *) AlignPage64K((unsigned long) start_address);
1221
                }
1222
        }
1223
        return NULL;
1224
 
1225
}
1226
 
1227
 
1228
void* wsbrk (long size)
1229
{
1230
        void* tmp;
1231
        if (size > 0)
1232
        {
1233
                if (gAddressBase == 0)
1234
                {
1235
                        gAllocatedSize = max (RESERVED_SIZE, AlignPage (size));
1236
                        gNextAddress = gAddressBase =
1237
                                (unsigned int)VirtualAlloc (NULL, gAllocatedSize,
1238
                                                                                        MEM_RESERVE, PAGE_NOACCESS);
1239
                } else if (AlignPage (gNextAddress + size) > (gAddressBase +
1240
gAllocatedSize))
1241
                {
1242
                        long new_size = max (NEXT_SIZE, AlignPage (size));
1243
                        void* new_address = (void*)(gAddressBase+gAllocatedSize);
1244
                        do
1245
                        {
1246
                                new_address = findRegion (new_address, new_size);
1247
 
1248
                                if (new_address == 0)
1249
                                        return (void*)-1;
1250
 
1251
                                gAddressBase = gNextAddress =
1252
                                        (unsigned int)VirtualAlloc (new_address, new_size,
1253
                                                                                                MEM_RESERVE, PAGE_NOACCESS);
1254
                                // repeat in case of race condition
1255
                                // The region that we found has been snagged 
1256
                                // by another thread
1257
                        }
1258
                        while (gAddressBase == 0);
1259
 
1260
                        assert (new_address == (void*)gAddressBase);
1261
 
1262
                        gAllocatedSize = new_size;
1263
 
1264
                        if (!makeGmListElement ((void*)gAddressBase))
1265
                                return (void*)-1;
1266
                }
1267
                if ((size + gNextAddress) > AlignPage (gNextAddress))
1268
                {
1269
                        void* res;
1270
                        res = VirtualAlloc ((void*)AlignPage (gNextAddress),
1271
                                                                (size + gNextAddress -
1272
                                                                 AlignPage (gNextAddress)),
1273
                                                                MEM_COMMIT, PAGE_READWRITE);
1274
                        if (res == 0)
1275
                                return (void*)-1;
1276
                }
1277
                tmp = (void*)gNextAddress;
1278
                gNextAddress = (unsigned int)tmp + size;
1279
                return tmp;
1280
        }
1281
        else if (size < 0)
1282
        {
1283
                unsigned int alignedGoal = AlignPage (gNextAddress + size);
1284
                /* Trim by releasing the virtual memory */
1285
                if (alignedGoal >= gAddressBase)
1286
                {
1287
                        VirtualFree ((void*)alignedGoal, gNextAddress - alignedGoal,
1288
                                                 MEM_DECOMMIT);
1289
                        gNextAddress = gNextAddress + size;
1290
                        return (void*)gNextAddress;
1291
                }
1292
                else
1293
                {
1294
                        VirtualFree ((void*)gAddressBase, gNextAddress - gAddressBase,
1295
                                                 MEM_DECOMMIT);
1296
                        gNextAddress = gAddressBase;
1297
                        return (void*)-1;
1298
                }
1299
        }
1300
        else
1301
        {
1302
                return (void*)gNextAddress;
1303
        }
1304
}
1305
 
1306
#endif
1307
 
1308
 
1309
 
1310
/*
1311
  Type declarations
1312
*/
1313
 
1314
 
1315
struct malloc_chunk
1316
{
1317
  INTERNAL_SIZE_T prev_size; /* Size of previous chunk (if free). */
1318
  INTERNAL_SIZE_T size;      /* Size in bytes, including overhead. */
1319
  struct malloc_chunk* fd;   /* double links -- used only if free. */
1320
  struct malloc_chunk* bk;
1321
};
1322
 
1323
typedef struct malloc_chunk* mchunkptr;
1324
 
1325
/*
1326
 
1327
   malloc_chunk details:
1328
 
1329
    (The following includes lightly edited explanations by Colin Plumb.)
1330
 
1331
    Chunks of memory are maintained using a `boundary tag' method as
1332
    described in e.g., Knuth or Standish.  (See the paper by Paul
1333
    Wilson ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a
1334
    survey of such techniques.)  Sizes of free chunks are stored both
1335
    in the front of each chunk and at the end.  This makes
1336
    consolidating fragmented chunks into bigger chunks very fast.  The
1337
    size fields also hold bits representing whether chunks are free or
1338
    in use.
1339
 
1340
    An allocated chunk looks like this:
1341
 
1342
 
1343
    chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1344
            |             Size of previous chunk, if allocated            | |
1345
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1346
            |             Size of chunk, in bytes                         |P|
1347
      mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1348
            |             User data starts here...                          .
1349
            .                                                               .
1350
            .             (malloc_usable_space() bytes)                     .
1351
            .                                                               |
1352
nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1353
            |             Size of chunk                                     |
1354
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1355
 
1356
 
1357
    Where "chunk" is the front of the chunk for the purpose of most of
1358
    the malloc code, but "mem" is the pointer that is returned to the
1359
    user.  "Nextchunk" is the beginning of the next contiguous chunk.
1360
 
1361
    Chunks always begin on even word boundries, so the mem portion
1362
    (which is returned to the user) is also on an even word boundary, and
1363
    thus double-word aligned.
1364
 
1365
    Free chunks are stored in circular doubly-linked lists, and look like this:
1366
 
1367
    chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1368
            |             Size of previous chunk                            |
1369
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1370
    `head:' |             Size of chunk, in bytes                         |P|
1371
      mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1372
            |             Forward pointer to next chunk in list             |
1373
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1374
            |             Back pointer to previous chunk in list            |
1375
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1376
            |             Unused space (may be 0 bytes long)                .
1377
            .                                                               .
1378
            .                                                               |
1379
nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1380
    `foot:' |             Size of chunk, in bytes                           |
1381
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1382
 
1383
    The P (PREV_INUSE) bit, stored in the unused low-order bit of the
1384
    chunk size (which is always a multiple of two words), is an in-use
1385
    bit for the *previous* chunk.  If that bit is *clear*, then the
1386
    word before the current chunk size contains the previous chunk
1387
    size, and can be used to find the front of the previous chunk.
1388
    (The very first chunk allocated always has this bit set,
1389
    preventing access to non-existent (or non-owned) memory.)
1390
 
1391
    Note that the `foot' of the current chunk is actually represented
1392
    as the prev_size of the NEXT chunk. (This makes it easier to
1393
    deal with alignments etc).
1394
 
1395
    The two exceptions to all this are
1396
 
1397
     1. The special chunk `top', which doesn't bother using the
1398
        trailing size field since there is no
1399
        next contiguous chunk that would have to index off it. (After
1400
        initialization, `top' is forced to always exist.  If it would
1401
        become less than MINSIZE bytes long, it is replenished via
1402
        malloc_extend_top.)
1403
 
1404
     2. Chunks allocated via mmap, which have the second-lowest-order
1405
        bit (IS_MMAPPED) set in their size fields.  Because they are
1406
        never merged or traversed from any other chunk, they have no
1407
        foot size or inuse information.
1408
 
1409
    Available chunks are kept in any of several places (all declared below):
1410
 
1411
    * `av': An array of chunks serving as bin headers for consolidated
1412
       chunks. Each bin is doubly linked.  The bins are approximately
1413
       proportionally (log) spaced.  There are a lot of these bins
1414
       (128). This may look excessive, but works very well in
1415
       practice.  All procedures maintain the invariant that no
1416
       consolidated chunk physically borders another one. Chunks in
1417
       bins are kept in size order, with ties going to the
1418
       approximately least recently used chunk.
1419
 
1420
       The chunks in each bin are maintained in decreasing sorted order by
1421
       size.  This is irrelevant for the small bins, which all contain
1422
       the same-sized chunks, but facilitates best-fit allocation for
1423
       larger chunks. (These lists are just sequential. Keeping them in
1424
       order almost never requires enough traversal to warrant using
1425
       fancier ordered data structures.)  Chunks of the same size are
1426
       linked with the most recently freed at the front, and allocations
1427
       are taken from the back.  This results in LRU or FIFO allocation
1428
       order, which tends to give each chunk an equal opportunity to be
1429
       consolidated with adjacent freed chunks, resulting in larger free
1430
       chunks and less fragmentation.
1431
 
1432
    * `top': The top-most available chunk (i.e., the one bordering the
1433
       end of available memory) is treated specially. It is never
1434
       included in any bin, is used only if no other chunk is
1435
       available, and is released back to the system if it is very
1436
       large (see M_TRIM_THRESHOLD).
1437
 
1438
    * `last_remainder': A bin holding only the remainder of the
1439
       most recently split (non-top) chunk. This bin is checked
1440
       before other non-fitting chunks, so as to provide better
1441
       locality for runs of sequentially allocated chunks.
1442
 
1443
    *  Implicitly, through the host system's memory mapping tables.
1444
       If supported, requests greater than a threshold are usually
1445
       serviced via calls to mmap, and then later released via munmap.
1446
 
1447
*/
1448
 
1449
 
1450
 
1451
 
1452
 
1453
 
1454
/*  sizes, alignments */
1455
 
1456
#define SIZE_SZ                (sizeof(INTERNAL_SIZE_T))
1457
#ifndef MALLOC_ALIGNMENT
1458
#define MALLOC_ALIGN           8
1459
#define MALLOC_ALIGNMENT       (SIZE_SZ + SIZE_SZ)
1460
#else
1461
#define MALLOC_ALIGN           MALLOC_ALIGNMENT
1462
#endif
1463
#define MALLOC_ALIGN_MASK      (MALLOC_ALIGNMENT - 1)
1464
#define MINSIZE                (sizeof(struct malloc_chunk))
1465
 
1466
/* conversion from malloc headers to user pointers, and back */
1467
 
1468
#define chunk2mem(p)   ((Void_t*)((char*)(p) + 2*SIZE_SZ))
1469
#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - 2*SIZE_SZ))
1470
 
1471
/* pad request bytes into a usable size */
1472
 
1473
#define request2size(req) \
1474
 (((long)((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) < \
1475
  (long)(MINSIZE + MALLOC_ALIGN_MASK)) ? ((MINSIZE + MALLOC_ALIGN_MASK) & ~(MALLOC_ALIGN_MASK)) : \
1476
   (((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) & ~(MALLOC_ALIGN_MASK)))
1477
 
1478
/* Check if m has acceptable alignment */
1479
 
1480
#define aligned_OK(m)    (((unsigned long)((m)) & (MALLOC_ALIGN_MASK)) == 0)
1481
 
1482
 
1483
 
1484
 
1485
/*
1486
  Physical chunk operations
1487
*/
1488
 
1489
 
1490
/* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */
1491
 
1492
#define PREV_INUSE 0x1 
1493
 
1494
/* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */
1495
 
1496
#define IS_MMAPPED 0x2
1497
 
1498
/* Bits to mask off when extracting size */
1499
 
1500
#define SIZE_BITS (PREV_INUSE|IS_MMAPPED)
1501
 
1502
 
1503
/* Ptr to next physical malloc_chunk. */
1504
 
1505
#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->size & ~PREV_INUSE) ))
1506
 
1507
/* Ptr to previous physical malloc_chunk */
1508
 
1509
#define prev_chunk(p)\
1510
   ((mchunkptr)( ((char*)(p)) - ((p)->prev_size) ))
1511
 
1512
 
1513
/* Treat space at ptr + offset as a chunk */
1514
 
1515
#define chunk_at_offset(p, s)  ((mchunkptr)(((char*)(p)) + (s)))
1516
 
1517
 
1518
 
1519
 
1520
/*
1521
  Dealing with use bits
1522
*/
1523
 
1524
/* extract p's inuse bit */
1525
 
1526
#define inuse(p)\
1527
((((mchunkptr)(((char*)(p))+((p)->size & ~PREV_INUSE)))->size) & PREV_INUSE)
1528
 
1529
/* extract inuse bit of previous chunk */
1530
 
1531
#define prev_inuse(p)  ((p)->size & PREV_INUSE)
1532
 
1533
/* check for mmap()'ed chunk */
1534
 
1535
#define chunk_is_mmapped(p) ((p)->size & IS_MMAPPED)
1536
 
1537
/* set/clear chunk as in use without otherwise disturbing */
1538
 
1539
#define set_inuse(p)\
1540
((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size |= PREV_INUSE
1541
 
1542
#define clear_inuse(p)\
1543
((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size &= ~(PREV_INUSE)
1544
 
1545
/* check/set/clear inuse bits in known places */
1546
 
1547
#define inuse_bit_at_offset(p, s)\
1548
 (((mchunkptr)(((char*)(p)) + (s)))->size & PREV_INUSE)
1549
 
1550
#define set_inuse_bit_at_offset(p, s)\
1551
 (((mchunkptr)(((char*)(p)) + (s)))->size |= PREV_INUSE)
1552
 
1553
#define clear_inuse_bit_at_offset(p, s)\
1554
 (((mchunkptr)(((char*)(p)) + (s)))->size &= ~(PREV_INUSE))
1555
 
1556
 
1557
 
1558
 
1559
/*
1560
  Dealing with size fields
1561
*/
1562
 
1563
/* Get size, ignoring use bits */
1564
 
1565
#define chunksize(p)          ((p)->size & ~(SIZE_BITS))
1566
 
1567
/* Set size at head, without disturbing its use bit */
1568
 
1569
#define set_head_size(p, s)   ((p)->size = (((p)->size & PREV_INUSE) | (s)))
1570
 
1571
/* Set size/use ignoring previous bits in header */
1572
 
1573
#define set_head(p, s)        ((p)->size = (s))
1574
 
1575
/* Set size at footer (only when chunk is not in use) */
1576
 
1577
#define set_foot(p, s)   (((mchunkptr)((char*)(p) + (s)))->prev_size = (s))
1578
 
1579
 
1580
 
1581
 
1582
 
1583
/*
1584
   Bins
1585
 
1586
    The bins, `av_' are an array of pairs of pointers serving as the
1587
    heads of (initially empty) doubly-linked lists of chunks, laid out
1588
    in a way so that each pair can be treated as if it were in a
1589
    malloc_chunk. (This way, the fd/bk offsets for linking bin heads
1590
    and chunks are the same).
1591
 
1592
    Bins for sizes < 512 bytes contain chunks of all the same size, spaced
1593
    8 bytes apart. Larger bins are approximately logarithmically
1594
    spaced. (See the table below.) The `av_' array is never mentioned
1595
    directly in the code, but instead via bin access macros.
1596
 
1597
    Bin layout:
1598
 
1599
    64 bins of size       8
1600
    32 bins of size      64
1601
    16 bins of size     512
1602
     8 bins of size    4096
1603
     4 bins of size   32768
1604
     2 bins of size  262144
1605
     1 bin  of size what's left
1606
 
1607
    There is actually a little bit of slop in the numbers in bin_index
1608
    for the sake of speed. This makes no difference elsewhere.
1609
 
1610
    The special chunks `top' and `last_remainder' get their own bins,
1611
    (this is implemented via yet more trickery with the av_ array),
1612
    although `top' is never properly linked to its bin since it is
1613
    always handled specially.
1614
 
1615
*/
1616
 
1617
#ifdef SEPARATE_OBJECTS
1618
#define av_ malloc_av_
1619
#endif
1620
 
1621
#define NAV             128   /* number of bins */
1622
 
1623
typedef struct malloc_chunk* mbinptr;
1624
 
1625
/* access macros */
1626
 
1627
#define bin_at(i)      ((mbinptr)((char*)&(av_[2*(i) + 2]) - 2*SIZE_SZ))
1628
#define next_bin(b)    ((mbinptr)((char*)(b) + 2 * sizeof(mbinptr)))
1629
#define prev_bin(b)    ((mbinptr)((char*)(b) - 2 * sizeof(mbinptr)))
1630
 
1631
/*
1632
   The first 2 bins are never indexed. The corresponding av_ cells are instead
1633
   used for bookkeeping. This is not to save space, but to simplify
1634
   indexing, maintain locality, and avoid some initialization tests.
1635
*/
1636
 
1637
#define top            (bin_at(0)->fd)   /* The topmost chunk */
1638
#define last_remainder (bin_at(1))       /* remainder from last split */
1639
 
1640
 
1641
/*
1642
   Because top initially points to its own bin with initial
1643
   zero size, thus forcing extension on the first malloc request,
1644
   we avoid having any special code in malloc to check whether
1645
   it even exists yet. But we still need to in malloc_extend_top.
1646
*/
1647
 
1648
#define initial_top    ((mchunkptr)(bin_at(0)))
1649
 
1650
/* Helper macro to initialize bins */
1651
 
1652
#define IAV(i)  bin_at(i), bin_at(i)
1653
 
1654
#ifdef DEFINE_MALLOC
1655
STATIC mbinptr av_[NAV * 2 + 2] = {
1656
 0, 0,
1657
 IAV(0),   IAV(1),   IAV(2),   IAV(3),   IAV(4),   IAV(5),   IAV(6),   IAV(7),
1658
 IAV(8),   IAV(9),   IAV(10),  IAV(11),  IAV(12),  IAV(13),  IAV(14),  IAV(15),
1659
 IAV(16),  IAV(17),  IAV(18),  IAV(19),  IAV(20),  IAV(21),  IAV(22),  IAV(23),
1660
 IAV(24),  IAV(25),  IAV(26),  IAV(27),  IAV(28),  IAV(29),  IAV(30),  IAV(31),
1661
 IAV(32),  IAV(33),  IAV(34),  IAV(35),  IAV(36),  IAV(37),  IAV(38),  IAV(39),
1662
 IAV(40),  IAV(41),  IAV(42),  IAV(43),  IAV(44),  IAV(45),  IAV(46),  IAV(47),
1663
 IAV(48),  IAV(49),  IAV(50),  IAV(51),  IAV(52),  IAV(53),  IAV(54),  IAV(55),
1664
 IAV(56),  IAV(57),  IAV(58),  IAV(59),  IAV(60),  IAV(61),  IAV(62),  IAV(63),
1665
 IAV(64),  IAV(65),  IAV(66),  IAV(67),  IAV(68),  IAV(69),  IAV(70),  IAV(71),
1666
 IAV(72),  IAV(73),  IAV(74),  IAV(75),  IAV(76),  IAV(77),  IAV(78),  IAV(79),
1667
 IAV(80),  IAV(81),  IAV(82),  IAV(83),  IAV(84),  IAV(85),  IAV(86),  IAV(87),
1668
 IAV(88),  IAV(89),  IAV(90),  IAV(91),  IAV(92),  IAV(93),  IAV(94),  IAV(95),
1669
 IAV(96),  IAV(97),  IAV(98),  IAV(99),  IAV(100), IAV(101), IAV(102), IAV(103),
1670
 IAV(104), IAV(105), IAV(106), IAV(107), IAV(108), IAV(109), IAV(110), IAV(111),
1671
 IAV(112), IAV(113), IAV(114), IAV(115), IAV(116), IAV(117), IAV(118), IAV(119),
1672
 IAV(120), IAV(121), IAV(122), IAV(123), IAV(124), IAV(125), IAV(126), IAV(127)
1673
};
1674
#else
1675
extern mbinptr av_[NAV * 2 + 2];
1676
#endif
1677
 
1678
 
1679
 
1680
/* field-extraction macros */
1681
 
1682
#define first(b) ((b)->fd)
1683
#define last(b)  ((b)->bk)
1684
 
1685
/*
1686
  Indexing into bins
1687
*/
1688
 
1689
#define bin_index(sz)                                                          \
1690
(((((unsigned long)(sz)) >> 9) ==    0) ?       (((unsigned long)(sz)) >>  3): \
1691
 ((((unsigned long)(sz)) >> 9) <=    4) ?  56 + (((unsigned long)(sz)) >>  6): \
1692
 ((((unsigned long)(sz)) >> 9) <=   20) ?  91 + (((unsigned long)(sz)) >>  9): \
1693
 ((((unsigned long)(sz)) >> 9) <=   84) ? 110 + (((unsigned long)(sz)) >> 12): \
1694
 ((((unsigned long)(sz)) >> 9) <=  340) ? 119 + (((unsigned long)(sz)) >> 15): \
1695
 ((((unsigned long)(sz)) >> 9) <= 1364) ? 124 + (((unsigned long)(sz)) >> 18): \
1696
                                          126)
1697
/*
1698
  bins for chunks < 512 are all spaced SMALLBIN_WIDTH bytes apart, and hold
1699
  identically sized chunks. This is exploited in malloc.
1700
*/
1701
 
1702
#define MAX_SMALLBIN_SIZE   512
1703
#define SMALLBIN_WIDTH        8
1704
#define SMALLBIN_WIDTH_BITS   3
1705
#define MAX_SMALLBIN        (MAX_SMALLBIN_SIZE / SMALLBIN_WIDTH) - 1
1706
 
1707
#define smallbin_index(sz)  (((unsigned long)(sz)) >> SMALLBIN_WIDTH_BITS)
1708
 
1709
/*
1710
   Requests are `small' if both the corresponding and the next bin are small
1711
*/
1712
 
1713
#define is_small_request(nb) (nb < MAX_SMALLBIN_SIZE - SMALLBIN_WIDTH)
1714
 
1715
 
1716
 
1717
/*
1718
    To help compensate for the large number of bins, a one-level index
1719
    structure is used for bin-by-bin searching.  `binblocks' is a
1720
    one-word bitvector recording whether groups of BINBLOCKWIDTH bins
1721
    have any (possibly) non-empty bins, so they can be skipped over
1722
    all at once during during traversals. The bits are NOT always
1723
    cleared as soon as all bins in a block are empty, but instead only
1724
    when all are noticed to be empty during traversal in malloc.
1725
*/
1726
 
1727
#define BINBLOCKWIDTH     4   /* bins per block */
1728
 
1729
#define binblocks      (bin_at(0)->size) /* bitvector of nonempty blocks */
1730
 
1731
/* bin<->block macros */
1732
 
1733
#define idx2binblock(ix)    ((unsigned long)1 << (ix / BINBLOCKWIDTH))
1734
#define mark_binblock(ii)   (binblocks |= idx2binblock(ii))
1735
#define clear_binblock(ii)  (binblocks &= ~(idx2binblock(ii)))
1736
 
1737
 
1738
 
1739
 
1740
 
1741
/*  Other static bookkeeping data */
1742
 
1743
#ifdef SEPARATE_OBJECTS
1744
#define trim_threshold          malloc_trim_threshold
1745
#define top_pad                 malloc_top_pad
1746
#define n_mmaps_max             malloc_n_mmaps_max
1747
#define mmap_threshold          malloc_mmap_threshold
1748
#define sbrk_base               malloc_sbrk_base
1749
#define max_sbrked_mem          malloc_max_sbrked_mem
1750
#define max_total_mem           malloc_max_total_mem
1751
#define current_mallinfo        malloc_current_mallinfo
1752
#define n_mmaps                 malloc_n_mmaps
1753
#define max_n_mmaps             malloc_max_n_mmaps
1754
#define mmapped_mem             malloc_mmapped_mem
1755
#define max_mmapped_mem         malloc_max_mmapped_mem
1756
#endif
1757
 
1758
/* variables holding tunable values */
1759
 
1760
#ifdef DEFINE_MALLOC
1761
 
1762
STATIC unsigned long trim_threshold   = DEFAULT_TRIM_THRESHOLD;
1763
STATIC unsigned long top_pad          = DEFAULT_TOP_PAD;
1764
#if HAVE_MMAP
1765
STATIC unsigned int  n_mmaps_max      = DEFAULT_MMAP_MAX;
1766
STATIC unsigned long mmap_threshold   = DEFAULT_MMAP_THRESHOLD;
1767
#endif
1768
 
1769
/* The first value returned from sbrk */
1770
STATIC char* sbrk_base = (char*)(-1);
1771
 
1772
/* The maximum memory obtained from system via sbrk */
1773
STATIC unsigned long max_sbrked_mem = 0;
1774
 
1775
/* The maximum via either sbrk or mmap */
1776
STATIC unsigned long max_total_mem = 0;
1777
 
1778
/* internal working copy of mallinfo */
1779
STATIC struct mallinfo current_mallinfo = {  0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
1780
 
1781
#if HAVE_MMAP
1782
 
1783
/* Tracking mmaps */
1784
 
1785
STATIC unsigned int n_mmaps = 0;
1786
STATIC unsigned int max_n_mmaps = 0;
1787
STATIC unsigned long mmapped_mem = 0;
1788
STATIC unsigned long max_mmapped_mem = 0;
1789
 
1790
#endif
1791
 
1792
#else /* ! DEFINE_MALLOC */
1793
 
1794
extern unsigned long trim_threshold;
1795
extern unsigned long top_pad;
1796
#if HAVE_MMAP
1797
extern unsigned int  n_mmaps_max;
1798
extern unsigned long mmap_threshold;
1799
#endif
1800
extern char* sbrk_base;
1801
extern unsigned long max_sbrked_mem;
1802
extern unsigned long max_total_mem;
1803
extern struct mallinfo current_mallinfo;
1804
#if HAVE_MMAP
1805
extern unsigned int n_mmaps;
1806
extern unsigned int max_n_mmaps;
1807
extern unsigned long mmapped_mem;
1808
extern unsigned long max_mmapped_mem;
1809
#endif
1810
 
1811
#endif /* ! DEFINE_MALLOC */
1812
 
1813
/* The total memory obtained from system via sbrk */
1814
#define sbrked_mem  (current_mallinfo.arena)
1815
 
1816
 
1817
 
1818
/*
1819
  Debugging support
1820
*/
1821
 
1822
#if DEBUG
1823
 
1824
 
1825
/*
1826
  These routines make a number of assertions about the states
1827
  of data structures that should be true at all times. If any
1828
  are not true, it's very likely that a user program has somehow
1829
  trashed memory. (It's also possible that there is a coding error
1830
  in malloc. In which case, please report it!)
1831
*/
1832
 
1833
#if __STD_C
1834
static void do_check_chunk(mchunkptr p)
1835
#else
1836
static void do_check_chunk(p) mchunkptr p;
1837
#endif
1838
{
1839
  INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE;
1840
 
1841
  /* No checkable chunk is mmapped */
1842
  assert(!chunk_is_mmapped(p));
1843
 
1844
  /* Check for legal address ... */
1845
  assert((char*)p >= sbrk_base);
1846
  if (p != top)
1847
    assert((char*)p + sz <= (char*)top);
1848
  else
1849
    assert((char*)p + sz <= sbrk_base + sbrked_mem);
1850
 
1851
}
1852
 
1853
 
1854
#if __STD_C
1855
static void do_check_free_chunk(mchunkptr p)
1856
#else
1857
static void do_check_free_chunk(p) mchunkptr p;
1858
#endif
1859
{
1860
  INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE;
1861
  mchunkptr next = chunk_at_offset(p, sz);
1862
 
1863
  do_check_chunk(p);
1864
 
1865
  /* Check whether it claims to be free ... */
1866
  assert(!inuse(p));
1867
 
1868
  /* Unless a special marker, must have OK fields */
1869
  if ((long)sz >= (long)MINSIZE)
1870
  {
1871
    assert((sz & MALLOC_ALIGN_MASK) == 0);
1872
    assert(aligned_OK(chunk2mem(p)));
1873
    /* ... matching footer field */
1874
    assert(next->prev_size == sz);
1875
    /* ... and is fully consolidated */
1876
    assert(prev_inuse(p));
1877
    assert (next == top || inuse(next));
1878
 
1879
    /* ... and has minimally sane links */
1880
    assert(p->fd->bk == p);
1881
    assert(p->bk->fd == p);
1882
  }
1883
  else /* markers are always of size SIZE_SZ */
1884
    assert(sz == SIZE_SZ);
1885
}
1886
 
1887
#if __STD_C
1888
static void do_check_inuse_chunk(mchunkptr p)
1889
#else
1890
static void do_check_inuse_chunk(p) mchunkptr p;
1891
#endif
1892
{
1893
  mchunkptr next = next_chunk(p);
1894
  do_check_chunk(p);
1895
 
1896
  /* Check whether it claims to be in use ... */
1897
  assert(inuse(p));
1898
 
1899
  /* ... and is surrounded by OK chunks.
1900
    Since more things can be checked with free chunks than inuse ones,
1901
    if an inuse chunk borders them and debug is on, it's worth doing them.
1902
  */
1903
  if (!prev_inuse(p))
1904
  {
1905
    mchunkptr prv = prev_chunk(p);
1906
    assert(next_chunk(prv) == p);
1907
    do_check_free_chunk(prv);
1908
  }
1909
  if (next == top)
1910
  {
1911
    assert(prev_inuse(next));
1912
    assert(chunksize(next) >= MINSIZE);
1913
  }
1914
  else if (!inuse(next))
1915
    do_check_free_chunk(next);
1916
 
1917
}
1918
 
1919
#if __STD_C
1920
static void do_check_malloced_chunk(mchunkptr p, INTERNAL_SIZE_T s)
1921
#else
1922
static void do_check_malloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s;
1923
#endif
1924
{
1925
  INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE;
1926
  long room = long_sub_size_t(sz, s);
1927
 
1928
  do_check_inuse_chunk(p);
1929
 
1930
  /* Legal size ... */
1931
  assert((long)sz >= (long)MINSIZE);
1932
  assert((sz & MALLOC_ALIGN_MASK) == 0);
1933
  assert(room >= 0);
1934
  assert(room < (long)MINSIZE);
1935
 
1936
  /* ... and alignment */
1937
  assert(aligned_OK(chunk2mem(p)));
1938
 
1939
 
1940
  /* ... and was allocated at front of an available chunk */
1941
  assert(prev_inuse(p));
1942
 
1943
}
1944
 
1945
 
1946
#define check_free_chunk(P)  do_check_free_chunk(P)
1947
#define check_inuse_chunk(P) do_check_inuse_chunk(P)
1948
#define check_chunk(P) do_check_chunk(P)
1949
#define check_malloced_chunk(P,N) do_check_malloced_chunk(P,N)
1950
#else
1951
#define check_free_chunk(P) 
1952
#define check_inuse_chunk(P)
1953
#define check_chunk(P)
1954
#define check_malloced_chunk(P,N)
1955
#endif
1956
 
1957
 
1958
 
1959
/*
1960
  Macro-based internal utilities
1961
*/
1962
 
1963
 
1964
/*
1965
  Linking chunks in bin lists.
1966
  Call these only with variables, not arbitrary expressions, as arguments.
1967
*/
1968
 
1969
/*
1970
  Place chunk p of size s in its bin, in size order,
1971
  putting it ahead of others of same size.
1972
*/
1973
 
1974
 
1975
#define frontlink(P, S, IDX, BK, FD)                                          \
1976
{                                                                             \
1977
  if (S < MAX_SMALLBIN_SIZE)                                                  \
1978
  {                                                                           \
1979
    IDX = smallbin_index(S);                                                  \
1980
    mark_binblock(IDX);                                                       \
1981
    BK = bin_at(IDX);                                                         \
1982
    FD = BK->fd;                                                              \
1983
    P->bk = BK;                                                               \
1984
    P->fd = FD;                                                               \
1985
    FD->bk = BK->fd = P;                                                      \
1986
  }                                                                           \
1987
  else                                                                        \
1988
  {                                                                           \
1989
    IDX = bin_index(S);                                                       \
1990
    BK = bin_at(IDX);                                                         \
1991
    FD = BK->fd;                                                              \
1992
    if (FD == BK) mark_binblock(IDX);                                         \
1993
    else                                                                      \
1994
    {                                                                         \
1995
      while (FD != BK && S < chunksize(FD)) FD = FD->fd;                      \
1996
      BK = FD->bk;                                                            \
1997
    }                                                                         \
1998
    P->bk = BK;                                                               \
1999
    P->fd = FD;                                                               \
2000
    FD->bk = BK->fd = P;                                                      \
2001
  }                                                                           \
2002
}
2003
 
2004
 
2005
/* take a chunk off a list */
2006
 
2007
#define unlink(P, BK, FD)                                                     \
2008
{                                                                             \
2009
  BK = P->bk;                                                                 \
2010
  FD = P->fd;                                                                 \
2011
  FD->bk = BK;                                                                \
2012
  BK->fd = FD;                                                                \
2013
}                                                                             \
2014
 
2015
/* Place p as the last remainder */
2016
 
2017
#define link_last_remainder(P)                                                \
2018
{                                                                             \
2019
  last_remainder->fd = last_remainder->bk =  P;                               \
2020
  P->fd = P->bk = last_remainder;                                             \
2021
}
2022
 
2023
/* Clear the last_remainder bin */
2024
 
2025
#define clear_last_remainder \
2026
  (last_remainder->fd = last_remainder->bk = last_remainder)
2027
 
2028
 
2029
 
2030
 
2031
 
2032
 
2033
/* Routines dealing with mmap(). */
2034
 
2035
#if HAVE_MMAP
2036
 
2037
#ifdef DEFINE_MALLOC
2038
 
2039
#if __STD_C
2040
static mchunkptr mmap_chunk(size_t size)
2041
#else
2042
static mchunkptr mmap_chunk(size) size_t size;
2043
#endif
2044
{
2045
  size_t page_mask = malloc_getpagesize - 1;
2046
  mchunkptr p;
2047
 
2048
#ifndef MAP_ANONYMOUS
2049
  static int fd = -1;
2050
#endif
2051
 
2052
  if(n_mmaps >= n_mmaps_max) return 0; /* too many regions */
2053
 
2054
  /* For mmapped chunks, the overhead is one SIZE_SZ unit larger, because
2055
   * there is no following chunk whose prev_size field could be used.
2056
   */
2057
  size = (size + SIZE_SZ + page_mask) & ~page_mask;
2058
 
2059
#ifdef MAP_ANONYMOUS
2060
  p = (mchunkptr)mmap(0, size, PROT_READ|PROT_WRITE,
2061
                      MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
2062
#else /* !MAP_ANONYMOUS */
2063
  if (fd < 0)
2064
  {
2065
    fd = open("/dev/zero", O_RDWR);
2066
    if(fd < 0) return 0;
2067
  }
2068
  p = (mchunkptr)mmap(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
2069
#endif
2070
 
2071
  if(p == (mchunkptr)-1) return 0;
2072
 
2073
  n_mmaps++;
2074
  if (n_mmaps > max_n_mmaps) max_n_mmaps = n_mmaps;
2075
 
2076
  /* We demand that eight bytes into a page must be 8-byte aligned. */
2077
  assert(aligned_OK(chunk2mem(p)));
2078
 
2079
  /* The offset to the start of the mmapped region is stored
2080
   * in the prev_size field of the chunk; normally it is zero,
2081
   * but that can be changed in memalign().
2082
   */
2083
  p->prev_size = 0;
2084
  set_head(p, size|IS_MMAPPED);
2085
 
2086
  mmapped_mem += size;
2087
  if ((unsigned long)mmapped_mem > (unsigned long)max_mmapped_mem)
2088
    max_mmapped_mem = mmapped_mem;
2089
  if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem)
2090
    max_total_mem = mmapped_mem + sbrked_mem;
2091
  return p;
2092
}
2093
 
2094
#endif /* DEFINE_MALLOC */
2095
 
2096
#ifdef SEPARATE_OBJECTS
2097
#define munmap_chunk malloc_munmap_chunk
2098
#endif
2099
 
2100
#ifdef DEFINE_FREE
2101
 
2102
#if __STD_C
2103
STATIC void munmap_chunk(mchunkptr p)
2104
#else
2105
STATIC void munmap_chunk(p) mchunkptr p;
2106
#endif
2107
{
2108
  INTERNAL_SIZE_T size = chunksize(p);
2109
  int ret;
2110
 
2111
  assert (chunk_is_mmapped(p));
2112
  assert(! ((char*)p >= sbrk_base && (char*)p < sbrk_base + sbrked_mem));
2113
  assert((n_mmaps > 0));
2114
  assert(((p->prev_size + size) & (malloc_getpagesize-1)) == 0);
2115
 
2116
  n_mmaps--;
2117
  mmapped_mem -= (size + p->prev_size);
2118
 
2119
  ret = munmap((char *)p - p->prev_size, size + p->prev_size);
2120
 
2121
  /* munmap returns non-zero on failure */
2122
  assert(ret == 0);
2123
}
2124
 
2125
#else /* ! DEFINE_FREE */
2126
 
2127
#if __STD_C
2128
extern void munmap_chunk(mchunkptr);
2129
#else
2130
extern void munmap_chunk();
2131
#endif
2132
 
2133
#endif /* ! DEFINE_FREE */
2134
 
2135
#if HAVE_MREMAP
2136
 
2137
#ifdef DEFINE_REALLOC
2138
 
2139
#if __STD_C
2140
static mchunkptr mremap_chunk(mchunkptr p, size_t new_size)
2141
#else
2142
static mchunkptr mremap_chunk(p, new_size) mchunkptr p; size_t new_size;
2143
#endif
2144
{
2145
  size_t page_mask = malloc_getpagesize - 1;
2146
  INTERNAL_SIZE_T offset = p->prev_size;
2147
  INTERNAL_SIZE_T size = chunksize(p);
2148
  char *cp;
2149
 
2150
  assert (chunk_is_mmapped(p));
2151
  assert(! ((char*)p >= sbrk_base && (char*)p < sbrk_base + sbrked_mem));
2152
  assert((n_mmaps > 0));
2153
  assert(((size + offset) & (malloc_getpagesize-1)) == 0);
2154
 
2155
  /* Note the extra SIZE_SZ overhead as in mmap_chunk(). */
2156
  new_size = (new_size + offset + SIZE_SZ + page_mask) & ~page_mask;
2157
 
2158
  cp = (char *)mremap((char *)p - offset, size + offset, new_size, 1);
2159
 
2160
  if (cp == (char *)-1) return 0;
2161
 
2162
  p = (mchunkptr)(cp + offset);
2163
 
2164
  assert(aligned_OK(chunk2mem(p)));
2165
 
2166
  assert((p->prev_size == offset));
2167
  set_head(p, (new_size - offset)|IS_MMAPPED);
2168
 
2169
  mmapped_mem -= size + offset;
2170
  mmapped_mem += new_size;
2171
  if ((unsigned long)mmapped_mem > (unsigned long)max_mmapped_mem)
2172
    max_mmapped_mem = mmapped_mem;
2173
  if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem)
2174
    max_total_mem = mmapped_mem + sbrked_mem;
2175
  return p;
2176
}
2177
 
2178
#endif /* DEFINE_REALLOC */
2179
 
2180
#endif /* HAVE_MREMAP */
2181
 
2182
#endif /* HAVE_MMAP */
2183
 
2184
 
2185
 
2186
 
2187
#ifdef DEFINE_MALLOC
2188
 
2189
/*
2190
  Extend the top-most chunk by obtaining memory from system.
2191
  Main interface to sbrk (but see also malloc_trim).
2192
*/
2193
 
2194
#if __STD_C
2195
static void malloc_extend_top(RARG INTERNAL_SIZE_T nb)
2196
#else
2197
static void malloc_extend_top(RARG nb) RDECL INTERNAL_SIZE_T nb;
2198
#endif
2199
{
2200
  char*     brk;                  /* return value from sbrk */
2201
  INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of sbrked space */
2202
  INTERNAL_SIZE_T correction;     /* bytes for 2nd sbrk call */
2203
  char*     new_brk;              /* return of 2nd sbrk call */
2204
  INTERNAL_SIZE_T top_size;       /* new size of top chunk */
2205
 
2206
  mchunkptr old_top     = top;  /* Record state of old top */
2207
  INTERNAL_SIZE_T old_top_size = chunksize(old_top);
2208
  char*     old_end      = (char*)(chunk_at_offset(old_top, old_top_size));
2209
 
2210
  /* Pad request with top_pad plus minimal overhead */
2211
 
2212
  INTERNAL_SIZE_T    sbrk_size     = nb + top_pad + MINSIZE;
2213
  unsigned long pagesz    = malloc_getpagesize;
2214
 
2215
  /* If not the first time through, round to preserve page boundary */
2216
  /* Otherwise, we need to correct to a page size below anyway. */
2217
  /* (We also correct below if an intervening foreign sbrk call.) */
2218
 
2219
  if (sbrk_base != (char*)(-1))
2220
    sbrk_size = (sbrk_size + (pagesz - 1)) & ~(pagesz - 1);
2221
 
2222
  brk = (char*)(MORECORE (sbrk_size));
2223
 
2224
  /* Fail if sbrk failed or if a foreign sbrk call killed our space */
2225
  if (brk == (char*)(MORECORE_FAILURE) ||
2226
      (brk < old_end && old_top != initial_top))
2227
    return;
2228
 
2229
  sbrked_mem += sbrk_size;
2230
 
2231
  if (brk == old_end) /* can just add bytes to current top */
2232
  {
2233
    top_size = sbrk_size + old_top_size;
2234
    set_head(top, top_size | PREV_INUSE);
2235
  }
2236
  else
2237
  {
2238
    if (sbrk_base == (char*)(-1))  /* First time through. Record base */
2239
      sbrk_base = brk;
2240
    else  /* Someone else called sbrk().  Count those bytes as sbrked_mem. */
2241
      sbrked_mem += brk - (char*)old_end;
2242
 
2243
    /* Guarantee alignment of first new chunk made from this space */
2244
    front_misalign = (POINTER_UINT)chunk2mem(brk) & MALLOC_ALIGN_MASK;
2245
    if (front_misalign > 0)
2246
    {
2247
      correction = (MALLOC_ALIGNMENT) - front_misalign;
2248
      brk += correction;
2249
    }
2250
    else
2251
      correction = 0;
2252
 
2253
    /* Guarantee the next brk will be at a page boundary */
2254
    correction += (((((POINTER_UINT)(brk + sbrk_size))+(pagesz-1)) &
2255
                    ~(pagesz - 1)) - ((POINTER_UINT)(brk + sbrk_size));
2256
 
2257
    /* Allocate correction */
2258
    new_brk = (char*)(MORECORE (correction));
2259
    if (new_brk == (char*)(MORECORE_FAILURE)) return;
2260
 
2261
    sbrked_mem += correction;
2262
 
2263
    top = (mchunkptr)brk;
2264
    top_size = new_brk - brk + correction;
2265
    set_head(top, top_size | PREV_INUSE);
2266
 
2267
    if (old_top != initial_top)
2268
    {
2269
 
2270
      /* There must have been an intervening foreign sbrk call. */
2271
      /* A double fencepost is necessary to prevent consolidation */
2272
 
2273
      /* If not enough space to do this, then user did something very wrong */
2274
      if (old_top_size < MINSIZE)
2275
      {
2276
        set_head(top, PREV_INUSE); /* will force null return from malloc */
2277
        return;
2278
      }
2279
 
2280
      /* Also keep size a multiple of MALLOC_ALIGNMENT */
2281
      old_top_size = (old_top_size - 3*SIZE_SZ) & ~MALLOC_ALIGN_MASK;
2282
      set_head_size(old_top, old_top_size);
2283
      chunk_at_offset(old_top, old_top_size          )->size =
2284
        SIZE_SZ|PREV_INUSE;
2285
      chunk_at_offset(old_top, old_top_size + SIZE_SZ)->size =
2286
        SIZE_SZ|PREV_INUSE;
2287
      /* If possible, release the rest. */
2288
      if (old_top_size >= MINSIZE)
2289
        fREe(RCALL chunk2mem(old_top));
2290
    }
2291
  }
2292
 
2293
  if ((unsigned long)sbrked_mem > (unsigned long)max_sbrked_mem)
2294
    max_sbrked_mem = sbrked_mem;
2295
#if HAVE_MMAP
2296
  if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem)
2297
    max_total_mem = mmapped_mem + sbrked_mem;
2298
#else
2299
  if ((unsigned long)(sbrked_mem) > (unsigned long)max_total_mem)
2300
    max_total_mem = sbrked_mem;
2301
#endif
2302
 
2303
  /* We always land on a page boundary */
2304
  assert(((unsigned long)((char*)top + top_size) & (pagesz - 1)) == 0);
2305
}
2306
 
2307
#endif /* DEFINE_MALLOC */
2308
 
2309
 
2310
/* Main public routines */
2311
 
2312
#ifdef DEFINE_MALLOC
2313
 
2314
/*
2315
  Malloc Algorthim:
2316
 
2317
    The requested size is first converted into a usable form, `nb'.
2318
    This currently means to add 4 bytes overhead plus possibly more to
2319
    obtain 8-byte alignment and/or to obtain a size of at least
2320
    MINSIZE (currently 16 bytes), the smallest allocatable size.
2321
    (All fits are considered `exact' if they are within MINSIZE bytes.)
2322
 
2323
    From there, the first successful of the following steps is taken:
2324
 
2325
      1. The bin corresponding to the request size is scanned, and if
2326
         a chunk of exactly the right size is found, it is taken.
2327
 
2328
      2. The most recently remaindered chunk is used if it is big
2329
         enough.  This is a form of (roving) first fit, used only in
2330
         the absence of exact fits. Runs of consecutive requests use
2331
         the remainder of the chunk used for the previous such request
2332
         whenever possible. This limited use of a first-fit style
2333
         allocation strategy tends to give contiguous chunks
2334
         coextensive lifetimes, which improves locality and can reduce
2335
         fragmentation in the long run.
2336
 
2337
      3. Other bins are scanned in increasing size order, using a
2338
         chunk big enough to fulfill the request, and splitting off
2339
         any remainder.  This search is strictly by best-fit; i.e.,
2340
         the smallest (with ties going to approximately the least
2341
         recently used) chunk that fits is selected.
2342
 
2343
      4. If large enough, the chunk bordering the end of memory
2344
         (`top') is split off. (This use of `top' is in accord with
2345
         the best-fit search rule.  In effect, `top' is treated as
2346
         larger (and thus less well fitting) than any other available
2347
         chunk since it can be extended to be as large as necessary
2348
         (up to system limitations).
2349
 
2350
      5. If the request size meets the mmap threshold and the
2351
         system supports mmap, and there are few enough currently
2352
         allocated mmapped regions, and a call to mmap succeeds,
2353
         the request is allocated via direct memory mapping.
2354
 
2355
      6. Otherwise, the top of memory is extended by
2356
         obtaining more space from the system (normally using sbrk,
2357
         but definable to anything else via the MORECORE macro).
2358
         Memory is gathered from the system (in system page-sized
2359
         units) in a way that allows chunks obtained across different
2360
         sbrk calls to be consolidated, but does not require
2361
         contiguous memory. Thus, it should be safe to intersperse
2362
         mallocs with other sbrk calls.
2363
 
2364
 
2365
      All allocations are made from the the `lowest' part of any found
2366
      chunk. (The implementation invariant is that prev_inuse is
2367
      always true of any allocated chunk; i.e., that each allocated
2368
      chunk borders either a previously allocated and still in-use chunk,
2369
      or the base of its memory arena.)
2370
 
2371
*/
2372
 
2373
#if __STD_C
2374
Void_t* mALLOc(RARG size_t bytes)
2375
#else
2376
Void_t* mALLOc(RARG bytes) RDECL size_t bytes;
2377
#endif
2378
{
2379
#ifdef MALLOC_PROVIDED
2380
 
2381
  malloc (bytes);
2382
 
2383
#else
2384
 
2385
  mchunkptr victim;                  /* inspected/selected chunk */
2386
  INTERNAL_SIZE_T victim_size;       /* its size */
2387
  int       idx;                     /* index for bin traversal */
2388
  mbinptr   bin;                     /* associated bin */
2389
  mchunkptr remainder;               /* remainder from a split */
2390
  long      remainder_size;          /* its size */
2391
  int       remainder_index;         /* its bin index */
2392
  unsigned long block;               /* block traverser bit */
2393
  int       startidx;                /* first bin of a traversed block */
2394
  mchunkptr fwd;                     /* misc temp for linking */
2395
  mchunkptr bck;                     /* misc temp for linking */
2396
  mbinptr q;                         /* misc temp */
2397
 
2398
  INTERNAL_SIZE_T nb;
2399
 
2400
  if ((long)bytes < 0) return 0;
2401
 
2402
  nb = request2size(bytes);  /* padded request size; */
2403
 
2404
  MALLOC_LOCK;
2405
 
2406
  /* Check for exact match in a bin */
2407
 
2408
  if (is_small_request(nb))  /* Faster version for small requests */
2409
  {
2410
    idx = smallbin_index(nb);
2411
 
2412
    /* No traversal or size check necessary for small bins.  */
2413
 
2414
    q = bin_at(idx);
2415
    victim = last(q);
2416
 
2417
#if MALLOC_ALIGN != 16
2418
    /* Also scan the next one, since it would have a remainder < MINSIZE */
2419
    if (victim == q)
2420
    {
2421
      q = next_bin(q);
2422
      victim = last(q);
2423
    }
2424
#endif
2425
    if (victim != q)
2426
    {
2427
      victim_size = chunksize(victim);
2428
      unlink(victim, bck, fwd);
2429
      set_inuse_bit_at_offset(victim, victim_size);
2430
      check_malloced_chunk(victim, nb);
2431
      MALLOC_UNLOCK;
2432
      return chunk2mem(victim);
2433
    }
2434
 
2435
    idx += 2; /* Set for bin scan below. We've already scanned 2 bins. */
2436
 
2437
  }
2438
  else
2439
  {
2440
    idx = bin_index(nb);
2441
    bin = bin_at(idx);
2442
 
2443
    for (victim = last(bin); victim != bin; victim = victim->bk)
2444
    {
2445
      victim_size = chunksize(victim);
2446
      remainder_size = long_sub_size_t(victim_size, nb);
2447
 
2448
      if (remainder_size >= (long)MINSIZE) /* too big */
2449
      {
2450
        --idx; /* adjust to rescan below after checking last remainder */
2451
        break;
2452
      }
2453
 
2454
      else if (remainder_size >= 0) /* exact fit */
2455
      {
2456
        unlink(victim, bck, fwd);
2457
        set_inuse_bit_at_offset(victim, victim_size);
2458
        check_malloced_chunk(victim, nb);
2459
        MALLOC_UNLOCK;
2460
        return chunk2mem(victim);
2461
      }
2462
    }
2463
 
2464
    ++idx;
2465
 
2466
  }
2467
 
2468
  /* Try to use the last split-off remainder */
2469
 
2470
  if ( (victim = last_remainder->fd) != last_remainder)
2471
  {
2472
    victim_size = chunksize(victim);
2473
    remainder_size = long_sub_size_t(victim_size, nb);
2474
 
2475
    if (remainder_size >= (long)MINSIZE) /* re-split */
2476
    {
2477
      remainder = chunk_at_offset(victim, nb);
2478
      set_head(victim, nb | PREV_INUSE);
2479
      link_last_remainder(remainder);
2480
      set_head(remainder, remainder_size | PREV_INUSE);
2481
      set_foot(remainder, remainder_size);
2482
      check_malloced_chunk(victim, nb);
2483
      MALLOC_UNLOCK;
2484
      return chunk2mem(victim);
2485
    }
2486
 
2487
    clear_last_remainder;
2488
 
2489
    if (remainder_size >= 0)  /* exhaust */
2490
    {
2491
      set_inuse_bit_at_offset(victim, victim_size);
2492
      check_malloced_chunk(victim, nb);
2493
      MALLOC_UNLOCK;
2494
      return chunk2mem(victim);
2495
    }
2496
 
2497
    /* Else place in bin */
2498
 
2499
    frontlink(victim, victim_size, remainder_index, bck, fwd);
2500
  }
2501
 
2502
  /*
2503
     If there are any possibly nonempty big-enough blocks,
2504
     search for best fitting chunk by scanning bins in blockwidth units.
2505
  */
2506
 
2507
  if ( (block = idx2binblock(idx)) <= binblocks)
2508
  {
2509
 
2510
    /* Get to the first marked block */
2511
 
2512
    if ( (block & binblocks) == 0)
2513
    {
2514
      /* force to an even block boundary */
2515
      idx = (idx & ~(BINBLOCKWIDTH - 1)) + BINBLOCKWIDTH;
2516
      block <<= 1;
2517
      while ((block & binblocks) == 0)
2518
      {
2519
        idx += BINBLOCKWIDTH;
2520
        block <<= 1;
2521
      }
2522
    }
2523
 
2524
    /* For each possibly nonempty block ... */
2525
    for (;;)
2526
    {
2527
      startidx = idx;          /* (track incomplete blocks) */
2528
      q = bin = bin_at(idx);
2529
 
2530
      /* For each bin in this block ... */
2531
      do
2532
      {
2533
        /* Find and use first big enough chunk ... */
2534
 
2535
        for (victim = last(bin); victim != bin; victim = victim->bk)
2536
        {
2537
          victim_size = chunksize(victim);
2538
          remainder_size = long_sub_size_t(victim_size, nb);
2539
 
2540
          if (remainder_size >= (long)MINSIZE) /* split */
2541
          {
2542
            remainder = chunk_at_offset(victim, nb);
2543
            set_head(victim, nb | PREV_INUSE);
2544
            unlink(victim, bck, fwd);
2545
            link_last_remainder(remainder);
2546
            set_head(remainder, remainder_size | PREV_INUSE);
2547
            set_foot(remainder, remainder_size);
2548
            check_malloced_chunk(victim, nb);
2549
            MALLOC_UNLOCK;
2550
            return chunk2mem(victim);
2551
          }
2552
 
2553
          else if (remainder_size >= 0)  /* take */
2554
          {
2555
            set_inuse_bit_at_offset(victim, victim_size);
2556
            unlink(victim, bck, fwd);
2557
            check_malloced_chunk(victim, nb);
2558
            MALLOC_UNLOCK;
2559
            return chunk2mem(victim);
2560
          }
2561
 
2562
        }
2563
 
2564
       bin = next_bin(bin);
2565
 
2566
#if MALLOC_ALIGN == 16
2567
       if (idx < MAX_SMALLBIN)
2568
         {
2569
           bin = next_bin(bin);
2570
           ++idx;
2571
         }
2572
#endif
2573
      } while ((++idx & (BINBLOCKWIDTH - 1)) != 0);
2574
 
2575
      /* Clear out the block bit. */
2576
 
2577
      do   /* Possibly backtrack to try to clear a partial block */
2578
      {
2579
        if ((startidx & (BINBLOCKWIDTH - 1)) == 0)
2580
        {
2581
          binblocks &= ~block;
2582
          break;
2583
        }
2584
        --startidx;
2585
       q = prev_bin(q);
2586
      } while (first(q) == q);
2587
 
2588
      /* Get to the next possibly nonempty block */
2589
 
2590
      if ( (block <<= 1) <= binblocks && (block != 0) )
2591
      {
2592
        while ((block & binblocks) == 0)
2593
        {
2594
          idx += BINBLOCKWIDTH;
2595
          block <<= 1;
2596
        }
2597
      }
2598
      else
2599
        break;
2600
    }
2601
  }
2602
 
2603
 
2604
  /* Try to use top chunk */
2605
 
2606
  /* Require that there be a remainder, ensuring top always exists  */
2607
  remainder_size = long_sub_size_t(chunksize(top), nb);
2608
  if (chunksize(top) < nb || remainder_size < (long)MINSIZE)
2609
  {
2610
 
2611
#if HAVE_MMAP
2612
    /* If big and would otherwise need to extend, try to use mmap instead */
2613
    if ((unsigned long)nb >= (unsigned long)mmap_threshold &&
2614
        (victim = mmap_chunk(nb)) != 0)
2615
    {
2616
      MALLOC_UNLOCK;
2617
      return chunk2mem(victim);
2618
    }
2619
#endif
2620
 
2621
    /* Try to extend */
2622
    malloc_extend_top(RCALL nb);
2623
    remainder_size = long_sub_size_t(chunksize(top), nb);
2624
    if (chunksize(top) < nb || remainder_size < (long)MINSIZE)
2625
    {
2626
      MALLOC_UNLOCK;
2627
      return 0; /* propagate failure */
2628
    }
2629
  }
2630
 
2631
  victim = top;
2632
  set_head(victim, nb | PREV_INUSE);
2633
  top = chunk_at_offset(victim, nb);
2634
  set_head(top, remainder_size | PREV_INUSE);
2635
  check_malloced_chunk(victim, nb);
2636
  MALLOC_UNLOCK;
2637
  return chunk2mem(victim);
2638
 
2639
#endif /* MALLOC_PROVIDED */
2640
}
2641
 
2642
#endif /* DEFINE_MALLOC */
2643
 
2644
#ifdef DEFINE_FREE
2645
 
2646
/*
2647
 
2648
  free() algorithm :
2649
 
2650
    cases:
2651
 
2652
       1. free(0) has no effect.
2653
 
2654
       2. If the chunk was allocated via mmap, it is release via munmap().
2655
 
2656
       3. If a returned chunk borders the current high end of memory,
2657
          it is consolidated into the top, and if the total unused
2658
          topmost memory exceeds the trim threshold, malloc_trim is
2659
          called.
2660
 
2661
       4. Other chunks are consolidated as they arrive, and
2662
          placed in corresponding bins. (This includes the case of
2663
          consolidating with the current `last_remainder').
2664
 
2665
*/
2666
 
2667
 
2668
#if __STD_C
2669
void fREe(RARG Void_t* mem)
2670
#else
2671
void fREe(RARG mem) RDECL Void_t* mem;
2672
#endif
2673
{
2674
#ifdef MALLOC_PROVIDED
2675
 
2676
  free (mem);
2677
 
2678
#else
2679
 
2680
  mchunkptr p;         /* chunk corresponding to mem */
2681
  INTERNAL_SIZE_T hd;  /* its head field */
2682
  INTERNAL_SIZE_T sz;  /* its size */
2683
  int       idx;       /* its bin index */
2684
  mchunkptr next;      /* next contiguous chunk */
2685
  INTERNAL_SIZE_T nextsz; /* its size */
2686
  INTERNAL_SIZE_T prevsz; /* size of previous contiguous chunk */
2687
  mchunkptr bck;       /* misc temp for linking */
2688
  mchunkptr fwd;       /* misc temp for linking */
2689
  int       islr;      /* track whether merging with last_remainder */
2690
 
2691
  if (mem == 0)                              /* free(0) has no effect */
2692
    return;
2693
 
2694
  MALLOC_LOCK;
2695
 
2696
  p = mem2chunk(mem);
2697
  hd = p->size;
2698
 
2699
#if HAVE_MMAP
2700
  if (hd & IS_MMAPPED)                       /* release mmapped memory. */
2701
  {
2702
    munmap_chunk(p);
2703
    MALLOC_UNLOCK;
2704
    return;
2705
  }
2706
#endif
2707
 
2708
  check_inuse_chunk(p);
2709
 
2710
  sz = hd & ~PREV_INUSE;
2711
  next = chunk_at_offset(p, sz);
2712
  nextsz = chunksize(next);
2713
 
2714
  if (next == top)                            /* merge with top */
2715
  {
2716
    sz += nextsz;
2717
 
2718
    if (!(hd & PREV_INUSE))                    /* consolidate backward */
2719
    {
2720
      prevsz = p->prev_size;
2721
      p = chunk_at_offset(p, -((long) prevsz));
2722
      sz += prevsz;
2723
      unlink(p, bck, fwd);
2724
    }
2725
 
2726
    set_head(p, sz | PREV_INUSE);
2727
    top = p;
2728
    if ((unsigned long)(sz) >= (unsigned long)trim_threshold)
2729
      malloc_trim(RCALL top_pad);
2730
    MALLOC_UNLOCK;
2731
    return;
2732
  }
2733
 
2734
  set_head(next, nextsz);                    /* clear inuse bit */
2735
 
2736
  islr = 0;
2737
 
2738
  if (!(hd & PREV_INUSE))                    /* consolidate backward */
2739
  {
2740
    prevsz = p->prev_size;
2741
    p = chunk_at_offset(p, -((long) prevsz));
2742
    sz += prevsz;
2743
 
2744
    if (p->fd == last_remainder)             /* keep as last_remainder */
2745
      islr = 1;
2746
    else
2747
      unlink(p, bck, fwd);
2748
  }
2749
 
2750
  if (!(inuse_bit_at_offset(next, nextsz)))   /* consolidate forward */
2751
  {
2752
    sz += nextsz;
2753
 
2754
    if (!islr && next->fd == last_remainder)  /* re-insert last_remainder */
2755
    {
2756
      islr = 1;
2757
      link_last_remainder(p);
2758
    }
2759
    else
2760
      unlink(next, bck, fwd);
2761
  }
2762
 
2763
 
2764
  set_head(p, sz | PREV_INUSE);
2765
  set_foot(p, sz);
2766
  if (!islr)
2767
    frontlink(p, sz, idx, bck, fwd);
2768
 
2769
  MALLOC_UNLOCK;
2770
 
2771
#endif /* MALLOC_PROVIDED */
2772
}
2773
 
2774
#endif /* DEFINE_FREE */
2775
 
2776
#ifdef DEFINE_REALLOC
2777
 
2778
/*
2779
 
2780
  Realloc algorithm:
2781
 
2782
    Chunks that were obtained via mmap cannot be extended or shrunk
2783
    unless HAVE_MREMAP is defined, in which case mremap is used.
2784
    Otherwise, if their reallocation is for additional space, they are
2785
    copied.  If for less, they are just left alone.
2786
 
2787
    Otherwise, if the reallocation is for additional space, and the
2788
    chunk can be extended, it is, else a malloc-copy-free sequence is
2789
    taken.  There are several different ways that a chunk could be
2790
    extended. All are tried:
2791
 
2792
       * Extending forward into following adjacent free chunk.
2793
       * Shifting backwards, joining preceding adjacent space
2794
       * Both shifting backwards and extending forward.
2795
       * Extending into newly sbrked space
2796
 
2797
    Unless the #define REALLOC_ZERO_BYTES_FREES is set, realloc with a
2798
    size argument of zero (re)allocates a minimum-sized chunk.
2799
 
2800
    If the reallocation is for less space, and the new request is for
2801
    a `small' (<512 bytes) size, then the newly unused space is lopped
2802
    off and freed.
2803
 
2804
    The old unix realloc convention of allowing the last-free'd chunk
2805
    to be used as an argument to realloc is no longer supported.
2806
    I don't know of any programs still relying on this feature,
2807
    and allowing it would also allow too many other incorrect
2808
    usages of realloc to be sensible.
2809
 
2810
 
2811
*/
2812
 
2813
 
2814
#if __STD_C
2815
Void_t* rEALLOc(RARG Void_t* oldmem, size_t bytes)
2816
#else
2817
Void_t* rEALLOc(RARG oldmem, bytes) RDECL Void_t* oldmem; size_t bytes;
2818
#endif
2819
{
2820
#ifdef MALLOC_PROVIDED
2821
 
2822
  realloc (oldmem, bytes);
2823
 
2824
#else
2825
 
2826
  INTERNAL_SIZE_T    nb;      /* padded request size */
2827
 
2828
  mchunkptr oldp;             /* chunk corresponding to oldmem */
2829
  INTERNAL_SIZE_T    oldsize; /* its size */
2830
 
2831
  mchunkptr newp;             /* chunk to return */
2832
  INTERNAL_SIZE_T    newsize; /* its size */
2833
  Void_t*   newmem;           /* corresponding user mem */
2834
 
2835
  mchunkptr next;             /* next contiguous chunk after oldp */
2836
  INTERNAL_SIZE_T  nextsize;  /* its size */
2837
 
2838
  mchunkptr prev;             /* previous contiguous chunk before oldp */
2839
  INTERNAL_SIZE_T  prevsize;  /* its size */
2840
 
2841
  mchunkptr remainder;        /* holds split off extra space from newp */
2842
  INTERNAL_SIZE_T  remainder_size;   /* its size */
2843
 
2844
  mchunkptr bck;              /* misc temp for linking */
2845
  mchunkptr fwd;              /* misc temp for linking */
2846
 
2847
#ifdef REALLOC_ZERO_BYTES_FREES
2848
  if (bytes == 0) { fREe(RCALL oldmem); return 0; }
2849
#endif
2850
 
2851
  if ((long)bytes < 0) return 0;
2852
 
2853
  /* realloc of null is supposed to be same as malloc */
2854
  if (oldmem == 0) return mALLOc(RCALL bytes);
2855
 
2856
  MALLOC_LOCK;
2857
 
2858
  newp    = oldp    = mem2chunk(oldmem);
2859
  newsize = oldsize = chunksize(oldp);
2860
 
2861
 
2862
  nb = request2size(bytes);
2863
 
2864
#if HAVE_MMAP
2865
  if (chunk_is_mmapped(oldp))
2866
  {
2867
#if HAVE_MREMAP
2868
    newp = mremap_chunk(oldp, nb);
2869
    if(newp)
2870
    {
2871
      MALLOC_UNLOCK;
2872
      return chunk2mem(newp);
2873
    }
2874
#endif
2875
    /* Note the extra SIZE_SZ overhead. */
2876
    if(oldsize - SIZE_SZ >= nb)
2877
    {
2878
      MALLOC_UNLOCK;
2879
      return oldmem; /* do nothing */
2880
    }
2881
    /* Must alloc, copy, free. */
2882
    newmem = mALLOc(RCALL bytes);
2883
    if (newmem == 0)
2884
    {
2885
      MALLOC_UNLOCK;
2886
      return 0; /* propagate failure */
2887
    }
2888
    MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ);
2889
    munmap_chunk(oldp);
2890
    MALLOC_UNLOCK;
2891
    return newmem;
2892
  }
2893
#endif
2894
 
2895
  check_inuse_chunk(oldp);
2896
 
2897
  if ((long)(oldsize) < (long)(nb))
2898
  {
2899
 
2900
    /* Try expanding forward */
2901
 
2902
    next = chunk_at_offset(oldp, oldsize);
2903
    if (next == top || !inuse(next))
2904
    {
2905
      nextsize = chunksize(next);
2906
 
2907
      /* Forward into top only if a remainder */
2908
      if (next == top)
2909
      {
2910
        if ((long)(nextsize + newsize) >= (long)(nb + MINSIZE))
2911
        {
2912
          newsize += nextsize;
2913
          top = chunk_at_offset(oldp, nb);
2914
          set_head(top, (newsize - nb) | PREV_INUSE);
2915
          set_head_size(oldp, nb);
2916
          MALLOC_UNLOCK;
2917
          return chunk2mem(oldp);
2918
        }
2919
      }
2920
 
2921
      /* Forward into next chunk */
2922
      else if (((long)(nextsize + newsize) >= (long)(nb)))
2923
      {
2924
        unlink(next, bck, fwd);
2925
        newsize  += nextsize;
2926
        goto split;
2927
      }
2928
    }
2929
    else
2930
    {
2931
      next = 0;
2932
      nextsize = 0;
2933
    }
2934
 
2935
    /* Try shifting backwards. */
2936
 
2937
    if (!prev_inuse(oldp))
2938
    {
2939
      prev = prev_chunk(oldp);
2940
      prevsize = chunksize(prev);
2941
 
2942
      /* try forward + backward first to save a later consolidation */
2943
 
2944
      if (next != 0)
2945
      {
2946
        /* into top */
2947
        if (next == top)
2948
        {
2949
          if ((long)(nextsize + prevsize + newsize) >= (long)(nb + MINSIZE))
2950
          {
2951
            unlink(prev, bck, fwd);
2952
            newp = prev;
2953
            newsize += prevsize + nextsize;
2954
            newmem = chunk2mem(newp);
2955
            MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ);
2956
            top = chunk_at_offset(newp, nb);
2957
            set_head(top, (newsize - nb) | PREV_INUSE);
2958
            set_head_size(newp, nb);
2959
            MALLOC_UNLOCK;
2960
            return newmem;
2961
          }
2962
        }
2963
 
2964
        /* into next chunk */
2965
        else if (((long)(nextsize + prevsize + newsize) >= (long)(nb)))
2966
        {
2967
          unlink(next, bck, fwd);
2968
          unlink(prev, bck, fwd);
2969
          newp = prev;
2970
          newsize += nextsize + prevsize;
2971
          newmem = chunk2mem(newp);
2972
          MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ);
2973
          goto split;
2974
        }
2975
      }
2976
 
2977
      /* backward only */
2978
      if (prev != 0 && (long)(prevsize + newsize) >= (long)nb)
2979
      {
2980
        unlink(prev, bck, fwd);
2981
        newp = prev;
2982
        newsize += prevsize;
2983
        newmem = chunk2mem(newp);
2984
        MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ);
2985
        goto split;
2986
      }
2987
    }
2988
 
2989
    /* Must allocate */
2990
 
2991
    newmem = mALLOc (RCALL bytes);
2992
 
2993
    if (newmem == 0)  /* propagate failure */
2994
    {
2995
      MALLOC_UNLOCK;
2996
      return 0;
2997
    }
2998
 
2999
    /* Avoid copy if newp is next chunk after oldp. */
3000
    /* (This can only happen when new chunk is sbrk'ed.) */
3001
 
3002
    if ( (newp = mem2chunk(newmem)) == next_chunk(oldp))
3003
    {
3004
      newsize += chunksize(newp);
3005
      newp = oldp;
3006
      goto split;
3007
    }
3008
 
3009
    /* Otherwise copy, free, and exit */
3010
    MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ);
3011
    fREe(RCALL oldmem);
3012
    MALLOC_UNLOCK;
3013
    return newmem;
3014
  }
3015
 
3016
 
3017
 split:  /* split off extra room in old or expanded chunk */
3018
 
3019
  remainder_size = long_sub_size_t(newsize, nb);
3020
 
3021
  if (remainder_size >= (long)MINSIZE) /* split off remainder */
3022
  {
3023
    remainder = chunk_at_offset(newp, nb);
3024
    set_head_size(newp, nb);
3025
    set_head(remainder, remainder_size | PREV_INUSE);
3026
    set_inuse_bit_at_offset(remainder, remainder_size);
3027
    fREe(RCALL chunk2mem(remainder)); /* let free() deal with it */
3028
  }
3029
  else
3030
  {
3031
    set_head_size(newp, newsize);
3032
    set_inuse_bit_at_offset(newp, newsize);
3033
  }
3034
 
3035
  check_inuse_chunk(newp);
3036
  MALLOC_UNLOCK;
3037
  return chunk2mem(newp);
3038
 
3039
#endif /* MALLOC_PROVIDED */
3040
}
3041
 
3042
#endif /* DEFINE_REALLOC */
3043
 
3044
#ifdef DEFINE_MEMALIGN
3045
 
3046
/*
3047
 
3048
  memalign algorithm:
3049
 
3050
    memalign requests more than enough space from malloc, finds a spot
3051
    within that chunk that meets the alignment request, and then
3052
    possibly frees the leading and trailing space.
3053
 
3054
    The alignment argument must be a power of two. This property is not
3055
    checked by memalign, so misuse may result in random runtime errors.
3056
 
3057
    8-byte alignment is guaranteed by normal malloc calls, so don't
3058
    bother calling memalign with an argument of 8 or less.
3059
 
3060
    Overreliance on memalign is a sure way to fragment space.
3061
 
3062
*/
3063
 
3064
 
3065
#if __STD_C
3066
Void_t* mEMALIGn(RARG size_t alignment, size_t bytes)
3067
#else
3068
Void_t* mEMALIGn(RARG alignment, bytes) RDECL size_t alignment; size_t bytes;
3069
#endif
3070
{
3071
  INTERNAL_SIZE_T    nb;      /* padded  request size */
3072
  char*     m;                /* memory returned by malloc call */
3073
  mchunkptr p;                /* corresponding chunk */
3074
  char*     brk;              /* alignment point within p */
3075
  mchunkptr newp;             /* chunk to return */
3076
  INTERNAL_SIZE_T  newsize;   /* its size */
3077
  INTERNAL_SIZE_T  leadsize;  /* leading space befor alignment point */
3078
  mchunkptr remainder;        /* spare room at end to split off */
3079
  long      remainder_size;   /* its size */
3080
 
3081
  if ((long)bytes < 0) return 0;
3082
 
3083
  /* If need less alignment than we give anyway, just relay to malloc */
3084
 
3085
  if (alignment <= MALLOC_ALIGNMENT) return mALLOc(RCALL bytes);
3086
 
3087
  /* Otherwise, ensure that it is at least a minimum chunk size */
3088
 
3089
  if (alignment <  MINSIZE) alignment = MINSIZE;
3090
 
3091
  /* Call malloc with worst case padding to hit alignment. */
3092
 
3093
  nb = request2size(bytes);
3094
  m  = (char*)(mALLOc(RCALL nb + alignment + MINSIZE));
3095
 
3096
  if (m == 0) return 0; /* propagate failure */
3097
 
3098
  MALLOC_LOCK;
3099
 
3100
  p = mem2chunk(m);
3101
 
3102
  if ((((unsigned long)(m)) % alignment) == 0) /* aligned */
3103
  {
3104
#if HAVE_MMAP
3105
    if(chunk_is_mmapped(p))
3106
    {
3107
      MALLOC_UNLOCK;
3108
      return chunk2mem(p); /* nothing more to do */
3109
    }
3110
#endif
3111
  }
3112
  else /* misaligned */
3113
  {
3114
    /*
3115
      Find an aligned spot inside chunk.
3116
      Since we need to give back leading space in a chunk of at
3117
      least MINSIZE, if the first calculation places us at
3118
      a spot with less than MINSIZE leader, we can move to the
3119
      next aligned spot -- we've allocated enough total room so that
3120
      this is always possible.
3121
    */
3122
 
3123
    brk = (char*)mem2chunk(((unsigned long)(m + alignment - 1)) & -((signed) alignment));
3124
    if ((long)(brk - (char*)(p)) < (long)MINSIZE) brk = brk + alignment;
3125
 
3126
    newp = (mchunkptr)brk;
3127
    leadsize = brk - (char*)(p);
3128
    newsize = chunksize(p) - leadsize;
3129
 
3130
#if HAVE_MMAP
3131
    if(chunk_is_mmapped(p))
3132
    {
3133
      newp->prev_size = p->prev_size + leadsize;
3134
      set_head(newp, newsize|IS_MMAPPED);
3135
      MALLOC_UNLOCK;
3136
      return chunk2mem(newp);
3137
    }
3138
#endif
3139
 
3140
    /* give back leader, use the rest */
3141
 
3142
    set_head(newp, newsize | PREV_INUSE);
3143
    set_inuse_bit_at_offset(newp, newsize);
3144
    set_head_size(p, leadsize);
3145
    fREe(RCALL chunk2mem(p));
3146
    p = newp;
3147
 
3148
    assert (newsize >= nb && (((unsigned long)(chunk2mem(p))) % alignment) == 0);
3149
  }
3150
 
3151
  /* Also give back spare room at the end */
3152
 
3153
  remainder_size = long_sub_size_t(chunksize(p), nb);
3154
 
3155
  if (remainder_size >= (long)MINSIZE)
3156
  {
3157
    remainder = chunk_at_offset(p, nb);
3158
    set_head(remainder, remainder_size | PREV_INUSE);
3159
    set_head_size(p, nb);
3160
    fREe(RCALL chunk2mem(remainder));
3161
  }
3162
 
3163
  check_inuse_chunk(p);
3164
  MALLOC_UNLOCK;
3165
  return chunk2mem(p);
3166
 
3167
}
3168
 
3169
#endif /* DEFINE_MEMALIGN */
3170
 
3171
#ifdef DEFINE_VALLOC
3172
 
3173
/*
3174
    valloc just invokes memalign with alignment argument equal
3175
    to the page size of the system (or as near to this as can
3176
    be figured out from all the includes/defines above.)
3177
*/
3178
 
3179
#if __STD_C
3180
Void_t* vALLOc(RARG size_t bytes)
3181
#else
3182
Void_t* vALLOc(RARG bytes) RDECL size_t bytes;
3183
#endif
3184
{
3185
  return mEMALIGn (RCALL malloc_getpagesize, bytes);
3186
}
3187
 
3188
#endif /* DEFINE_VALLOC */
3189
 
3190
#ifdef DEFINE_PVALLOC
3191
 
3192
/*
3193
  pvalloc just invokes valloc for the nearest pagesize
3194
  that will accommodate request
3195
*/
3196
 
3197
 
3198
#if __STD_C
3199
Void_t* pvALLOc(RARG size_t bytes)
3200
#else
3201
Void_t* pvALLOc(RARG bytes) RDECL size_t bytes;
3202
#endif
3203
{
3204
  size_t pagesize = malloc_getpagesize;
3205
  return mEMALIGn (RCALL pagesize, (bytes + pagesize - 1) & ~(pagesize - 1));
3206
}
3207
 
3208
#endif /* DEFINE_PVALLOC */
3209
 
3210
#ifdef DEFINE_CALLOC
3211
 
3212
/*
3213
 
3214
  calloc calls malloc, then zeroes out the allocated chunk.
3215
 
3216
*/
3217
 
3218
#if __STD_C
3219
Void_t* cALLOc(RARG size_t n, size_t elem_size)
3220
#else
3221
Void_t* cALLOc(RARG n, elem_size) RDECL size_t n; size_t elem_size;
3222
#endif
3223
{
3224
  mchunkptr p;
3225
  INTERNAL_SIZE_T csz;
3226
 
3227
  INTERNAL_SIZE_T sz = n * elem_size;
3228
 
3229
#if MORECORE_CLEARS
3230
  mchunkptr oldtop;
3231
  INTERNAL_SIZE_T oldtopsize;
3232
#endif
3233
  Void_t* mem;
3234
 
3235
 
3236
  /* check if expand_top called, in which case don't need to clear */
3237
#if MORECORE_CLEARS
3238
  MALLOC_LOCK;
3239
  oldtop = top;
3240
  oldtopsize = chunksize(top);
3241
#endif
3242
 
3243
  mem = mALLOc (RCALL sz);
3244
 
3245
  if ((long)n < 0) return 0;
3246
 
3247
  if (mem == 0)
3248
  {
3249
#if MORECORE_CLEARS
3250
    MALLOC_UNLOCK;
3251
#endif
3252
    return 0;
3253
  }
3254
  else
3255
  {
3256
    p = mem2chunk(mem);
3257
 
3258
    /* Two optional cases in which clearing not necessary */
3259
 
3260
 
3261
#if HAVE_MMAP
3262
    if (chunk_is_mmapped(p))
3263
    {
3264
#if MORECORE_CLEARS
3265
      MALLOC_UNLOCK;
3266
#endif
3267
      return mem;
3268
    }
3269
#endif
3270
 
3271
    csz = chunksize(p);
3272
 
3273
#if MORECORE_CLEARS
3274
    if (p == oldtop && csz > oldtopsize)
3275
    {
3276
      /* clear only the bytes from non-freshly-sbrked memory */
3277
      csz = oldtopsize;
3278
    }
3279
    MALLOC_UNLOCK;
3280
#endif
3281
 
3282
    MALLOC_ZERO(mem, csz - SIZE_SZ);
3283
    return mem;
3284
  }
3285
}
3286
 
3287
#endif /* DEFINE_CALLOC */
3288
 
3289
#ifdef DEFINE_CFREE
3290
 
3291
/*
3292
 
3293
  cfree just calls free. It is needed/defined on some systems
3294
  that pair it with calloc, presumably for odd historical reasons.
3295
 
3296
*/
3297
 
3298
#if !defined(INTERNAL_LINUX_C_LIB) || !defined(__ELF__)
3299
#if !defined(INTERNAL_NEWLIB) || !defined(_REENT_ONLY)
3300
#if __STD_C
3301
void cfree(Void_t *mem)
3302
#else
3303
void cfree(mem) Void_t *mem;
3304
#endif
3305
{
3306
#ifdef INTERNAL_NEWLIB
3307
  fREe(_REENT, mem);
3308
#else
3309
  fREe(mem);
3310
#endif
3311
}
3312
#endif
3313
#endif
3314
 
3315
#endif /* DEFINE_CFREE */
3316
 
3317
#ifdef DEFINE_FREE
3318
 
3319
/*
3320
 
3321
    Malloc_trim gives memory back to the system (via negative
3322
    arguments to sbrk) if there is unused memory at the `high' end of
3323
    the malloc pool. You can call this after freeing large blocks of
3324
    memory to potentially reduce the system-level memory requirements
3325
    of a program. However, it cannot guarantee to reduce memory. Under
3326
    some allocation patterns, some large free blocks of memory will be
3327
    locked between two used chunks, so they cannot be given back to
3328
    the system.
3329
 
3330
    The `pad' argument to malloc_trim represents the amount of free
3331
    trailing space to leave untrimmed. If this argument is zero,
3332
    only the minimum amount of memory to maintain internal data
3333
    structures will be left (one page or less). Non-zero arguments
3334
    can be supplied to maintain enough trailing space to service
3335
    future expected allocations without having to re-obtain memory
3336
    from the system.
3337
 
3338
    Malloc_trim returns 1 if it actually released any memory, else 0.
3339
 
3340
*/
3341
 
3342
#if __STD_C
3343
int malloc_trim(RARG size_t pad)
3344
#else
3345
int malloc_trim(RARG pad) RDECL size_t pad;
3346
#endif
3347
{
3348
  long  top_size;        /* Amount of top-most memory */
3349
  long  extra;           /* Amount to release */
3350
  char* current_brk;     /* address returned by pre-check sbrk call */
3351
  char* new_brk;         /* address returned by negative sbrk call */
3352
 
3353
  unsigned long pagesz = malloc_getpagesize;
3354
 
3355
  MALLOC_LOCK;
3356
 
3357
  top_size = chunksize(top);
3358
  extra = ((top_size - pad - MINSIZE + (pagesz-1)) / pagesz - 1) * pagesz;
3359
 
3360
  if (extra < (long)pagesz)  /* Not enough memory to release */
3361
  {
3362
    MALLOC_UNLOCK;
3363
    return 0;
3364
  }
3365
 
3366
  else
3367
  {
3368
    /* Test to make sure no one else called sbrk */
3369
    current_brk = (char*)(MORECORE (0));
3370
    if (current_brk != (char*)(top) + top_size)
3371
    {
3372
      MALLOC_UNLOCK;
3373
      return 0;     /* Apparently we don't own memory; must fail */
3374
    }
3375
 
3376
    else
3377
    {
3378
      new_brk = (char*)(MORECORE (-extra));
3379
 
3380
      if (new_brk == (char*)(MORECORE_FAILURE)) /* sbrk failed? */
3381
      {
3382
        /* Try to figure out what we have */
3383
        current_brk = (char*)(MORECORE (0));
3384
        top_size = current_brk - (char*)top;
3385
        if (top_size >= (long)MINSIZE) /* if not, we are very very dead! */
3386
        {
3387
          sbrked_mem = current_brk - sbrk_base;
3388
          set_head(top, top_size | PREV_INUSE);
3389
        }
3390
        check_chunk(top);
3391
        MALLOC_UNLOCK;
3392
        return 0;
3393
      }
3394
 
3395
      else
3396
      {
3397
        /* Success. Adjust top accordingly. */
3398
        set_head(top, (top_size - extra) | PREV_INUSE);
3399
        sbrked_mem -= extra;
3400
        check_chunk(top);
3401
        MALLOC_UNLOCK;
3402
        return 1;
3403
      }
3404
    }
3405
  }
3406
}
3407
 
3408
#endif /* DEFINE_FREE */
3409
 
3410
#ifdef DEFINE_MALLOC_USABLE_SIZE
3411
 
3412
/*
3413
  malloc_usable_size:
3414
 
3415
    This routine tells you how many bytes you can actually use in an
3416
    allocated chunk, which may be more than you requested (although
3417
    often not). You can use this many bytes without worrying about
3418
    overwriting other allocated objects. Not a particularly great
3419
    programming practice, but still sometimes useful.
3420
 
3421
*/
3422
 
3423
#if __STD_C
3424
size_t malloc_usable_size(RARG Void_t* mem)
3425
#else
3426
size_t malloc_usable_size(RARG mem) RDECL Void_t* mem;
3427
#endif
3428
{
3429
  mchunkptr p;
3430
  if (mem == 0)
3431
    return 0;
3432
  else
3433
  {
3434
    p = mem2chunk(mem);
3435
    if(!chunk_is_mmapped(p))
3436
    {
3437
      if (!inuse(p)) return 0;
3438
#if DEBUG
3439
      MALLOC_LOCK;
3440
      check_inuse_chunk(p);
3441
      MALLOC_UNLOCK;
3442
#endif
3443
      return chunksize(p) - SIZE_SZ;
3444
    }
3445
    return chunksize(p) - 2*SIZE_SZ;
3446
  }
3447
}
3448
 
3449
#endif /* DEFINE_MALLOC_USABLE_SIZE */
3450
 
3451
#ifdef DEFINE_MALLINFO
3452
 
3453
/* Utility to update current_mallinfo for malloc_stats and mallinfo() */
3454
 
3455
STATIC void malloc_update_mallinfo()
3456
{
3457
  int i;
3458
  mbinptr b;
3459
  mchunkptr p;
3460
#if DEBUG
3461
  mchunkptr q;
3462
#endif
3463
 
3464
  INTERNAL_SIZE_T avail = chunksize(top);
3465
  int   navail = ((long)(avail) >= (long)MINSIZE)? 1 : 0;
3466
 
3467
  for (i = 1; i < NAV; ++i)
3468
  {
3469
    b = bin_at(i);
3470
    for (p = last(b); p != b; p = p->bk)
3471
    {
3472
#if DEBUG
3473
      check_free_chunk(p);
3474
      for (q = next_chunk(p);
3475
           q < top && inuse(q) && (long)(chunksize(q)) >= (long)MINSIZE;
3476
           q = next_chunk(q))
3477
        check_inuse_chunk(q);
3478
#endif
3479
      avail += chunksize(p);
3480
      navail++;
3481
    }
3482
  }
3483
 
3484
  current_mallinfo.ordblks = navail;
3485
  current_mallinfo.uordblks = sbrked_mem - avail;
3486
  current_mallinfo.fordblks = avail;
3487
#if HAVE_MMAP
3488
  current_mallinfo.hblks = n_mmaps;
3489
  current_mallinfo.hblkhd = mmapped_mem;
3490
#endif
3491
  current_mallinfo.keepcost = chunksize(top);
3492
 
3493
}
3494
 
3495
#else /* ! DEFINE_MALLINFO */
3496
 
3497
#if __STD_C
3498
extern void malloc_update_mallinfo(void);
3499
#else
3500
extern void malloc_update_mallinfo();
3501
#endif
3502
 
3503
#endif /* ! DEFINE_MALLINFO */
3504
 
3505
#ifdef DEFINE_MALLOC_STATS
3506
 
3507
/*
3508
 
3509
  malloc_stats:
3510
 
3511
    Prints on stderr the amount of space obtain from the system (both
3512
    via sbrk and mmap), the maximum amount (which may be more than
3513
    current if malloc_trim and/or munmap got called), the maximum
3514
    number of simultaneous mmap regions used, and the current number
3515
    of bytes allocated via malloc (or realloc, etc) but not yet
3516
    freed. (Note that this is the number of bytes allocated, not the
3517
    number requested. It will be larger than the number requested
3518
    because of alignment and bookkeeping overhead.)
3519
 
3520
*/
3521
 
3522
#if __STD_C
3523
void malloc_stats(RONEARG)
3524
#else
3525
void malloc_stats(RONEARG) RDECL
3526
#endif
3527
{
3528
  unsigned long local_max_total_mem;
3529
  int local_sbrked_mem;
3530
  struct mallinfo local_mallinfo;
3531
#if HAVE_MMAP
3532
  unsigned long local_mmapped_mem, local_max_n_mmaps;
3533
#endif
3534
  FILE *fp;
3535
 
3536
  MALLOC_LOCK;
3537
  malloc_update_mallinfo();
3538
  local_max_total_mem = max_total_mem;
3539
  local_sbrked_mem = sbrked_mem;
3540
  local_mallinfo = current_mallinfo;
3541
#if HAVE_MMAP
3542
  local_mmapped_mem = mmapped_mem;
3543
  local_max_n_mmaps = max_n_mmaps;
3544
#endif
3545
  MALLOC_UNLOCK;
3546
 
3547
#ifdef INTERNAL_NEWLIB
3548
  fp = _stderr_r(reent_ptr);
3549
#define fprintf fiprintf
3550
#else
3551
  fp = stderr;
3552
#endif
3553
 
3554
  fprintf(fp, "max system bytes = %10u\n",
3555
          (unsigned int)(local_max_total_mem));
3556
#if HAVE_MMAP
3557
  fprintf(fp, "system bytes     = %10u\n",
3558
          (unsigned int)(local_sbrked_mem + local_mmapped_mem));
3559
  fprintf(fp, "in use bytes     = %10u\n",
3560
          (unsigned int)(local_mallinfo.uordblks + local_mmapped_mem));
3561
#else
3562
  fprintf(fp, "system bytes     = %10u\n",
3563
          (unsigned int)local_sbrked_mem);
3564
  fprintf(fp, "in use bytes     = %10u\n",
3565
          (unsigned int)local_mallinfo.uordblks);
3566
#endif
3567
#if HAVE_MMAP
3568
  fprintf(fp, "max mmap regions = %10u\n",
3569
          (unsigned int)local_max_n_mmaps);
3570
#endif
3571
}
3572
 
3573
#endif /* DEFINE_MALLOC_STATS */
3574
 
3575
#ifdef DEFINE_MALLINFO
3576
 
3577
/*
3578
  mallinfo returns a copy of updated current mallinfo.
3579
*/
3580
 
3581
#if __STD_C
3582
struct mallinfo mALLINFo(RONEARG)
3583
#else
3584
struct mallinfo mALLINFo(RONEARG) RDECL
3585
#endif
3586
{
3587
  struct mallinfo ret;
3588
 
3589
  MALLOC_LOCK;
3590
  malloc_update_mallinfo();
3591
  ret = current_mallinfo;
3592
  MALLOC_UNLOCK;
3593
  return ret;
3594
}
3595
 
3596
#endif /* DEFINE_MALLINFO */
3597
 
3598
#ifdef DEFINE_MALLOPT
3599
 
3600
/*
3601
  mallopt:
3602
 
3603
    mallopt is the general SVID/XPG interface to tunable parameters.
3604
    The format is to provide a (parameter-number, parameter-value) pair.
3605
    mallopt then sets the corresponding parameter to the argument
3606
    value if it can (i.e., so long as the value is meaningful),
3607
    and returns 1 if successful else 0.
3608
 
3609
    See descriptions of tunable parameters above.
3610
 
3611
*/
3612
 
3613
#if __STD_C
3614
int mALLOPt(RARG int param_number, int value)
3615
#else
3616
int mALLOPt(RARG param_number, value) RDECL int param_number; int value;
3617
#endif
3618
{
3619
  MALLOC_LOCK;
3620
  switch(param_number)
3621
  {
3622
    case M_TRIM_THRESHOLD:
3623
      trim_threshold = value; MALLOC_UNLOCK; return 1;
3624
    case M_TOP_PAD:
3625
      top_pad = value; MALLOC_UNLOCK; return 1;
3626
    case M_MMAP_THRESHOLD:
3627
#if HAVE_MMAP
3628
      mmap_threshold = value;
3629
#endif
3630
      MALLOC_UNLOCK;
3631
      return 1;
3632
    case M_MMAP_MAX:
3633
#if HAVE_MMAP
3634
      n_mmaps_max = value; MALLOC_UNLOCK; return 1;
3635
#else
3636
      MALLOC_UNLOCK; return value == 0;
3637
#endif
3638
 
3639
    default:
3640
      MALLOC_UNLOCK;
3641
      return 0;
3642
  }
3643
}
3644
 
3645
#endif /* DEFINE_MALLOPT */
3646
 
3647
/*
3648
 
3649
History:
3650
 
3651
    V2.6.6 Sun Dec  5 07:42:19 1999  Doug Lea  (dl at gee)
3652
      * return null for negative arguments
3653
      * Added Several WIN32 cleanups from Martin C. Fong <mcfong@yahoo.com>
3654
         * Add 'LACKS_SYS_PARAM_H' for those systems without 'sys/param.h'
3655
          (e.g. WIN32 platforms)
3656
         * Cleanup up header file inclusion for WIN32 platforms
3657
         * Cleanup code to avoid Microsoft Visual C++ compiler complaints
3658
         * Add 'USE_DL_PREFIX' to quickly allow co-existence with existing
3659
           memory allocation routines
3660
         * Set 'malloc_getpagesize' for WIN32 platforms (needs more work)
3661
         * Use 'assert' rather than 'ASSERT' in WIN32 code to conform to
3662
           usage of 'assert' in non-WIN32 code
3663
         * Improve WIN32 'sbrk()' emulation's 'findRegion()' routine to
3664
           avoid infinite loop
3665
      * Always call 'fREe()' rather than 'free()'
3666
 
3667
    V2.6.5 Wed Jun 17 15:57:31 1998  Doug Lea  (dl at gee)
3668
      * Fixed ordering problem with boundary-stamping
3669
 
3670
    V2.6.3 Sun May 19 08:17:58 1996  Doug Lea  (dl at gee)
3671
      * Added pvalloc, as recommended by H.J. Liu
3672
      * Added 64bit pointer support mainly from Wolfram Gloger
3673
      * Added anonymously donated WIN32 sbrk emulation
3674
      * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen
3675
      * malloc_extend_top: fix mask error that caused wastage after
3676
        foreign sbrks
3677
      * Add linux mremap support code from HJ Liu
3678
 
3679
    V2.6.2 Tue Dec  5 06:52:55 1995  Doug Lea  (dl at gee)
3680
      * Integrated most documentation with the code.
3681
      * Add support for mmap, with help from
3682
        Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
3683
      * Use last_remainder in more cases.
3684
      * Pack bins using idea from  colin@nyx10.cs.du.edu
3685
      * Use ordered bins instead of best-fit threshhold
3686
      * Eliminate block-local decls to simplify tracing and debugging.
3687
      * Support another case of realloc via move into top
3688
      * Fix error occuring when initial sbrk_base not word-aligned.
3689
      * Rely on page size for units instead of SBRK_UNIT to
3690
        avoid surprises about sbrk alignment conventions.
3691
      * Add mallinfo, mallopt. Thanks to Raymond Nijssen
3692
        (raymond@es.ele.tue.nl) for the suggestion.
3693
      * Add `pad' argument to malloc_trim and top_pad mallopt parameter.
3694
      * More precautions for cases where other routines call sbrk,
3695
        courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
3696
      * Added macros etc., allowing use in linux libc from
3697
        H.J. Lu (hjl@gnu.ai.mit.edu)
3698
      * Inverted this history list
3699
 
3700
    V2.6.1 Sat Dec  2 14:10:57 1995  Doug Lea  (dl at gee)
3701
      * Re-tuned and fixed to behave more nicely with V2.6.0 changes.
3702
      * Removed all preallocation code since under current scheme
3703
        the work required to undo bad preallocations exceeds
3704
        the work saved in good cases for most test programs.
3705
      * No longer use return list or unconsolidated bins since
3706
        no scheme using them consistently outperforms those that don't
3707
        given above changes.
3708
      * Use best fit for very large chunks to prevent some worst-cases.
3709
      * Added some support for debugging
3710
 
3711
    V2.6.0 Sat Nov  4 07:05:23 1995  Doug Lea  (dl at gee)
3712
      * Removed footers when chunks are in use. Thanks to
3713
        Paul Wilson (wilson@cs.texas.edu) for the suggestion.
3714
 
3715
    V2.5.4 Wed Nov  1 07:54:51 1995  Doug Lea  (dl at gee)
3716
      * Added malloc_trim, with help from Wolfram Gloger
3717
        (wmglo@Dent.MED.Uni-Muenchen.DE).
3718
 
3719
    V2.5.3 Tue Apr 26 10:16:01 1994  Doug Lea  (dl at g)
3720
 
3721
    V2.5.2 Tue Apr  5 16:20:40 1994  Doug Lea  (dl at g)
3722
      * realloc: try to expand in both directions
3723
      * malloc: swap order of clean-bin strategy;
3724
      * realloc: only conditionally expand backwards
3725
      * Try not to scavenge used bins
3726
      * Use bin counts as a guide to preallocation
3727
      * Occasionally bin return list chunks in first scan
3728
      * Add a few optimizations from colin@nyx10.cs.du.edu
3729
 
3730
    V2.5.1 Sat Aug 14 15:40:43 1993  Doug Lea  (dl at g)
3731
      * faster bin computation & slightly different binning
3732
      * merged all consolidations to one part of malloc proper
3733
         (eliminating old malloc_find_space & malloc_clean_bin)
3734
      * Scan 2 returns chunks (not just 1)
3735
      * Propagate failure in realloc if malloc returns 0
3736
      * Add stuff to allow compilation on non-ANSI compilers
3737
          from kpv@research.att.com
3738
 
3739
    V2.5 Sat Aug  7 07:41:59 1993  Doug Lea  (dl at g.oswego.edu)
3740
      * removed potential for odd address access in prev_chunk
3741
      * removed dependency on getpagesize.h
3742
      * misc cosmetics and a bit more internal documentation
3743
      * anticosmetics: mangled names in macros to evade debugger strangeness
3744
      * tested on sparc, hp-700, dec-mips, rs6000
3745
          with gcc & native cc (hp, dec only) allowing
3746
          Detlefs & Zorn comparison study (in SIGPLAN Notices.)
3747
 
3748
    Trial version Fri Aug 28 13:14:29 1992  Doug Lea  (dl at g.oswego.edu)
3749
      * Based loosely on libg++-1.2X malloc. (It retains some of the overall
3750
         structure of old version,  but most details differ.)
3751
 
3752
*/
3753
 

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