source: vendor/perl/5.8.8/malloc.c@ 3539

Last change on this file since 3539 was 3181, checked in by bird, 19 years ago

perl 5.8.8
File size: 75.7 KB
Line 
1/* malloc.c
2 *
3 */
4
5/*
6 * "'The Chamber of Records,' said Gimli. 'I guess that is where we now stand.'"
7 */
8
9/* This file contains Perl's own implementation of the malloc library.
10 * It is used if Configure decides that, on your platform, Perl's
11 * version is better than the OS's, or if you give Configure the
12 * -Dusemymalloc command-line option.
13 */
14
15/*
16 Here are some notes on configuring Perl's malloc. (For non-perl
17 usage see below.)
18
19 There are two macros which serve as bulk disablers of advanced
20 features of this malloc: NO_FANCY_MALLOC, PLAIN_MALLOC (undef by
21 default). Look in the list of default values below to understand
22 their exact effect. Defining NO_FANCY_MALLOC returns malloc.c to the
23 state of the malloc in Perl 5.004. Additionally defining PLAIN_MALLOC
24 returns it to the state as of Perl 5.000.
25
26 Note that some of the settings below may be ignored in the code based
27 on values of other macros. The PERL_CORE symbol is only defined when
28 perl itself is being compiled (so malloc can make some assumptions
29 about perl's facilities being available to it).
30
31 Each config option has a short description, followed by its name,
32 default value, and a comment about the default (if applicable). Some
33 options take a precise value, while the others are just boolean.
34 The boolean ones are listed first.
35
36 # Read configuration settings from malloc_cfg.h
37 HAVE_MALLOC_CFG_H undef
38
39 # Enable code for an emergency memory pool in $^M. See perlvar.pod
40 # for a description of $^M.
41 PERL_EMERGENCY_SBRK (!PLAIN_MALLOC && (PERL_CORE || !NO_MALLOC_DYNAMIC_CFG))
42
43 # Enable code for printing memory statistics.
44 DEBUGGING_MSTATS (!PLAIN_MALLOC && PERL_CORE)
45
46 # Move allocation info for small buckets into separate areas.
47 # Memory optimization (especially for small allocations, of the
48 # less than 64 bytes). Since perl usually makes a large number
49 # of small allocations, this is usually a win.
50 PACK_MALLOC (!PLAIN_MALLOC && !RCHECK)
51
52 # Add one page to big powers of two when calculating bucket size.
53 # This is targeted at big allocations, as are common in image
54 # processing.
55 TWO_POT_OPTIMIZE !PLAIN_MALLOC
56
57 # Use intermediate bucket sizes between powers-of-two. This is
58 # generally a memory optimization, and a (small) speed pessimization.
59 BUCKETS_ROOT2 !NO_FANCY_MALLOC
60
61 # Do not check small deallocations for bad free(). Memory
62 # and speed optimization, error reporting pessimization.
63 IGNORE_SMALL_BAD_FREE (!NO_FANCY_MALLOC && !RCHECK)
64
65 # Use table lookup to decide in which bucket a given allocation will go.
66 SMALL_BUCKET_VIA_TABLE !NO_FANCY_MALLOC
67
68 # Use a perl-defined sbrk() instead of the (presumably broken or
69 # missing) system-supplied sbrk().
70 USE_PERL_SBRK undef
71
72 # Use system malloc() (or calloc() etc.) to emulate sbrk(). Normally
73 # only used with broken sbrk()s.
74 PERL_SBRK_VIA_MALLOC undef
75
76 # Which allocator to use if PERL_SBRK_VIA_MALLOC
77 SYSTEM_ALLOC(a) malloc(a)
78
79 # Minimal alignment (in bytes, should be a power of 2) of SYSTEM_ALLOC
80 SYSTEM_ALLOC_ALIGNMENT MEM_ALIGNBYTES
81
82 # Disable memory overwrite checking with DEBUGGING. Memory and speed
83 # optimization, error reporting pessimization.
84 NO_RCHECK undef
85
86 # Enable memory overwrite checking with DEBUGGING. Memory and speed
87 # pessimization, error reporting optimization
88 RCHECK (DEBUGGING && !NO_RCHECK)
89
90 # Do not overwrite uninit areas with DEBUGGING. Speed
91 # optimization, error reporting pessimization
92 NO_MFILL undef
93
94 # Overwrite uninit areas with DEBUGGING. Speed
95 # pessimization, error reporting optimization
96 MALLOC_FILL (DEBUGGING && !NO_RCHECK && !NO_MFILL)
97
98 # Do not check overwritten uninit areas with DEBUGGING. Speed
99 # optimization, error reporting pessimization
100 NO_FILL_CHECK undef
101
102 # Check overwritten uninit areas with DEBUGGING. Speed
103 # pessimization, error reporting optimization
104 MALLOC_FILL_CHECK (DEBUGGING && !NO_RCHECK && !NO_FILL_CHECK)
105
106 # Failed allocations bigger than this size croak (if
107 # PERL_EMERGENCY_SBRK is enabled) without touching $^M. See
108 # perlvar.pod for a description of $^M.
109 BIG_SIZE (1<<16) # 64K
110
111 # Starting from this power of two, add an extra page to the
112 # size of the bucket. This enables optimized allocations of sizes
113 # close to powers of 2. Note that the value is indexed at 0.
114 FIRST_BIG_POW2 15 # 32K, 16K is used too often
115
116 # Estimate of minimal memory footprint. malloc uses this value to
117 # request the most reasonable largest blocks of memory from the system.
118 FIRST_SBRK (48*1024)
119
120 # Round up sbrk()s to multiples of this.
121 MIN_SBRK 2048
122
123 # Round up sbrk()s to multiples of this percent of footprint.
124 MIN_SBRK_FRAC 3
125
126 # Round up sbrk()s to multiples of this multiple of 1/1000 of footprint.
127 MIN_SBRK_FRAC1000 (10 * MIN_SBRK_FRAC)
128
129 # Add this much memory to big powers of two to get the bucket size.
130 PERL_PAGESIZE 4096
131
132 # This many sbrk() discontinuities should be tolerated even
133 # from the start without deciding that sbrk() is usually
134 # discontinuous.
135 SBRK_ALLOW_FAILURES 3
136
137 # This many continuous sbrk()s compensate for one discontinuous one.
138 SBRK_FAILURE_PRICE 50
139
140 # Some configurations may ask for 12-byte-or-so allocations which
141 # require 8-byte alignment (?!). In such situation one needs to
142 # define this to disable 12-byte bucket (will increase memory footprint)
143 STRICT_ALIGNMENT undef
144
145 # Do not allow configuration of runtime options at runtime
146 NO_MALLOC_DYNAMIC_CFG undef
147
148 # Do not allow configuration of runtime options via $ENV{PERL_MALLOC_OPT}
149 NO_PERL_MALLOC_ENV undef
150
151 [The variable consists of ;-separated parts of the form CODE=VALUE
152 with 1-character codes F, M, f, A, P, G, d, a, c for runtime
153 configuration of FIRST_SBRK, MIN_SBRK, MIN_SBRK_FRAC1000,
154 SBRK_ALLOW_FAILURES, SBRK_FAILURE_PRICE, sbrk_goodness,
155 filldead, fillalive, fillcheck. The last 3 are for DEBUGGING
156 build, and allow switching the tests for free()ed memory read,
157 uninit memory reads, and free()ed memory write.]
158
159 This implementation assumes that calling PerlIO_printf() does not
160 result in any memory allocation calls (used during a panic).
161
162 */
163
164/*
165 If used outside of Perl environment, it may be useful to redefine
166 the following macros (listed below with defaults):
167
168 # Type of address returned by allocation functions
169 Malloc_t void *
170
171 # Type of size argument for allocation functions
172 MEM_SIZE unsigned long
173
174 # size of void*
175 PTRSIZE 4
176
177 # Maximal value in LONG
178 LONG_MAX 0x7FFFFFFF
179
180 # Unsigned integer type big enough to keep a pointer
181 UV unsigned long
182
183 # Signed integer of the same sizeof() as UV
184 IV long
185
186 # Type of pointer with 1-byte granularity
187 caddr_t char *
188
189 # Type returned by free()
190 Free_t void
191
192 # Conversion of pointer to integer
193 PTR2UV(ptr) ((UV)(ptr))
194
195 # Conversion of integer to pointer
196 INT2PTR(type, i) ((type)(i))
197
198 # printf()-%-Conversion of UV to pointer
199 UVuf "lu"
200
201 # printf()-%-Conversion of UV to hex pointer
202 UVxf "lx"
203
204 # Alignment to use
205 MEM_ALIGNBYTES 4
206
207 # Very fatal condition reporting function (cannot call any )
208 fatalcroak(arg) write(2,arg,strlen(arg)) + exit(2)
209
210 # Fatal error reporting function
211 croak(format, arg) warn(idem) + exit(1)
212
213 # Fatal error reporting function
214 croak2(format, arg1, arg2) warn2(idem) + exit(1)
215
216 # Error reporting function
217 warn(format, arg) fprintf(stderr, idem)
218
219 # Error reporting function
220 warn2(format, arg1, arg2) fprintf(stderr, idem)
221
222 # Locking/unlocking for MT operation
223 MALLOC_LOCK MUTEX_LOCK(&PL_malloc_mutex)
224 MALLOC_UNLOCK MUTEX_UNLOCK(&PL_malloc_mutex)
225
226 # Locking/unlocking mutex for MT operation
227 MUTEX_LOCK(l) void
228 MUTEX_UNLOCK(l) void
229 */
230
231#ifdef HAVE_MALLOC_CFG_H
232# include "malloc_cfg.h"
233#endif
234
235#ifndef NO_FANCY_MALLOC
236# ifndef SMALL_BUCKET_VIA_TABLE
237# define SMALL_BUCKET_VIA_TABLE
238# endif
239# ifndef BUCKETS_ROOT2
240# define BUCKETS_ROOT2
241# endif
242# ifndef IGNORE_SMALL_BAD_FREE
243# define IGNORE_SMALL_BAD_FREE
244# endif
245#endif
246
247#ifndef PLAIN_MALLOC /* Bulk enable features */
248# ifndef PACK_MALLOC
249# define PACK_MALLOC
250# endif
251# ifndef TWO_POT_OPTIMIZE
252# define TWO_POT_OPTIMIZE
253# endif
254# if (defined(PERL_CORE) || !defined(NO_MALLOC_DYNAMIC_CFG)) && !defined(PERL_EMERGENCY_SBRK)
255# define PERL_EMERGENCY_SBRK
256# endif
257# if defined(PERL_CORE) && !defined(DEBUGGING_MSTATS)
258# define DEBUGGING_MSTATS
259# endif
260#endif
261
262#define MIN_BUC_POW2 (sizeof(void*) > 4 ? 3 : 2) /* Allow for 4-byte arena. */
263#define MIN_BUCKET (MIN_BUC_POW2 * BUCKETS_PER_POW2)
264
265#if !(defined(I286) || defined(atarist) || defined(__MINT__))
266 /* take 2k unless the block is bigger than that */
267# define LOG_OF_MIN_ARENA 11
268#else
269 /* take 16k unless the block is bigger than that
270 (80286s like large segments!), probably good on the atari too */
271# define LOG_OF_MIN_ARENA 14
272#endif
273
274#if defined(DEBUGGING) && !defined(NO_RCHECK)
275# define RCHECK
276#endif
277#if defined(DEBUGGING) && !defined(NO_RCHECK) && !defined(NO_MFILL) && !defined(MALLOC_FILL)
278# define MALLOC_FILL
279#endif
280#if defined(DEBUGGING) && !defined(NO_RCHECK) && !defined(NO_FILL_CHECK) && !defined(MALLOC_FILL_CHECK)
281# define MALLOC_FILL_CHECK
282#endif
283#if defined(RCHECK) && defined(IGNORE_SMALL_BAD_FREE)
284# undef IGNORE_SMALL_BAD_FREE
285#endif
286/*
287 * malloc.c (Caltech) 2/21/82
288 * Chris Kingsley, kingsley@cit-20.
289 *
290 * This is a very fast storage allocator. It allocates blocks of a small
291 * number of different sizes, and keeps free lists of each size. Blocks that
292 * don't exactly fit are passed up to the next larger size. In this
293 * implementation, the available sizes are 2^n-4 (or 2^n-12) bytes long.
294 * If PACK_MALLOC is defined, small blocks are 2^n bytes long.
295 * This is designed for use in a program that uses vast quantities of memory,
296 * but bombs when it runs out.
297 *
298 * Modifications Copyright Ilya Zakharevich 1996-99.
299 *
300 * Still very quick, but much more thrifty. (Std config is 10% slower
301 * than it was, and takes 67% of old heap size for typical usage.)
302 *
303 * Allocations of small blocks are now table-driven to many different
304 * buckets. Sizes of really big buckets are increased to accomodata
305 * common size=power-of-2 blocks. Running-out-of-memory is made into
306 * an exception. Deeply configurable and thread-safe.
307 *
308 */
309
310#ifdef PERL_CORE
311# include "EXTERN.h"
312# define PERL_IN_MALLOC_C
313# include "perl.h"
314# if defined(PERL_IMPLICIT_CONTEXT)
315# define croak Perl_croak_nocontext
316# define croak2 Perl_croak_nocontext
317# define warn Perl_warn_nocontext
318# define warn2 Perl_warn_nocontext
319# else
320# define croak2 croak
321# define warn2 warn
322# endif
323# if defined(USE_5005THREADS) || defined(USE_ITHREADS)
324# define PERL_MAYBE_ALIVE PL_thr_key
325# else
326# define PERL_MAYBE_ALIVE 1
327# endif
328#else
329# ifdef PERL_FOR_X2P
330# include "../EXTERN.h"
331# include "../perl.h"
332# else
333# include <stdlib.h>
334# include <stdio.h>
335# include <memory.h>
336# ifdef OS2
337# include <io.h>
338# endif
339# include <string.h>
340# ifndef Malloc_t
341# define Malloc_t void *
342# endif
343# ifndef PTRSIZE
344# define PTRSIZE 4
345# endif
346# ifndef MEM_SIZE
347# define MEM_SIZE unsigned long
348# endif
349# ifndef LONG_MAX
350# define LONG_MAX 0x7FFFFFFF
351# endif
352# ifndef UV
353# define UV unsigned long
354# endif
355# ifndef IV
356# define IV long
357# endif
358# ifndef caddr_t
359# define caddr_t char *
360# endif
361# ifndef Free_t
362# define Free_t void
363# endif
364# define Copy(s,d,n,t) (void)memcpy((char*)(d),(char*)(s), (n) * sizeof(t))
365# define CopyD(s,d,n,t) memcpy((char*)(d),(char*)(s), (n) * sizeof(t))
366# define PerlEnv_getenv getenv
367# define PerlIO_printf fprintf
368# define PerlIO_stderr() stderr
369# define PerlIO_puts(f,s) fputs(s,f)
370# ifndef INT2PTR
371# define INT2PTR(t,i) ((t)(i))
372# endif
373# ifndef PTR2UV
374# define PTR2UV(p) ((UV)(p))
375# endif
376# ifndef UVuf
377# define UVuf "lu"
378# endif
379# ifndef UVxf
380# define UVxf "lx"
381# endif
382# ifndef Nullch
383# define Nullch NULL
384# endif
385# ifndef MEM_ALIGNBYTES
386# define MEM_ALIGNBYTES 4
387# endif
388# endif
389# ifndef croak /* make depend */
390# define croak(mess, arg) (warn((mess), (arg)), exit(1))
391# endif
392# ifndef croak2 /* make depend */
393# define croak2(mess, arg1, arg2) (warn2((mess), (arg1), (arg2)), exit(1))
394# endif
395# ifndef warn
396# define warn(mess, arg) fprintf(stderr, (mess), (arg))
397# endif
398# ifndef warn2
399# define warn2(mess, arg1, arg2) fprintf(stderr, (mess), (arg1), (arg2))
400# endif
401# ifdef DEBUG_m
402# undef DEBUG_m
403# endif
404# define DEBUG_m(a)
405# ifdef DEBUGGING
406# undef DEBUGGING
407# endif
408# ifndef pTHX
409# define pTHX void
410# define pTHX_
411# ifdef HASATTRIBUTE_UNUSED
412# define dTHX extern int Perl___notused PERL_UNUSED_DECL
413# else
414# define dTHX extern int Perl___notused
415# endif
416# define WITH_THX(s) s
417# endif
418# ifndef PERL_GET_INTERP
419# define PERL_GET_INTERP PL_curinterp
420# endif
421# define PERL_MAYBE_ALIVE 1
422# ifndef Perl_malloc
423# define Perl_malloc malloc
424# endif
425# ifndef Perl_mfree
426# define Perl_mfree free
427# endif
428# ifndef Perl_realloc
429# define Perl_realloc realloc
430# endif
431# ifndef Perl_calloc
432# define Perl_calloc calloc
433# endif
434# ifndef Perl_strdup
435# define Perl_strdup strdup
436# endif
437#endif /* defined PERL_CORE */
438
439#ifndef MUTEX_LOCK
440# define MUTEX_LOCK(l)
441#endif
442
443#ifndef MUTEX_UNLOCK
444# define MUTEX_UNLOCK(l)
445#endif
446
447#ifndef MALLOC_LOCK
448# define MALLOC_LOCK MUTEX_LOCK(&PL_malloc_mutex)
449#endif
450
451#ifndef MALLOC_UNLOCK
452# define MALLOC_UNLOCK MUTEX_UNLOCK(&PL_malloc_mutex)
453#endif
454
455# ifndef fatalcroak /* make depend */
456# define fatalcroak(mess) (write(2, (mess), strlen(mess)), exit(2))
457# endif
458
459#ifdef DEBUGGING
460# undef DEBUG_m
461# define DEBUG_m(a) \
462 STMT_START { \
463 if (PERL_MAYBE_ALIVE && PERL_GET_THX) { \
464 dTHX; \
465 if (DEBUG_m_TEST) { \
466 PL_debug &= ~DEBUG_m_FLAG; \
467 a; \
468 PL_debug |= DEBUG_m_FLAG; \
469 } \
470 } \
471 } STMT_END
472#endif
473
474#ifdef PERL_IMPLICIT_CONTEXT
475# define PERL_IS_ALIVE aTHX
476#else
477# define PERL_IS_ALIVE TRUE
478#endif
479
480
481/*
482 * Layout of memory:
483 * ~~~~~~~~~~~~~~~~
484 * The memory is broken into "blocks" which occupy multiples of 2K (and
485 * generally speaking, have size "close" to a power of 2). The addresses
486 * of such *unused* blocks are kept in nextf[i] with big enough i. (nextf
487 * is an array of linked lists.) (Addresses of used blocks are not known.)
488 *
489 * Moreover, since the algorithm may try to "bite" smaller blocks out
490 * of unused bigger ones, there are also regions of "irregular" size,
491 * managed separately, by a linked list chunk_chain.
492 *
493 * The third type of storage is the sbrk()ed-but-not-yet-used space, its
494 * end and size are kept in last_sbrk_top and sbrked_remains.
495 *
496 * Growing blocks "in place":
497 * ~~~~~~~~~~~~~~~~~~~~~~~~~
498 * The address of the block with the greatest address is kept in last_op
499 * (if not known, last_op is 0). If it is known that the memory above
500 * last_op is not continuous, or contains a chunk from chunk_chain,
501 * last_op is set to 0.
502 *
503 * The chunk with address last_op may be grown by expanding into
504 * sbrk()ed-but-not-yet-used space, or trying to sbrk() more continuous
505 * memory.
506 *
507 * Management of last_op:
508 * ~~~~~~~~~~~~~~~~~~~~~
509 *
510 * free() never changes the boundaries of blocks, so is not relevant.
511 *
512 * The only way realloc() may change the boundaries of blocks is if it
513 * grows a block "in place". However, in the case of success such a
514 * chunk is automatically last_op, and it remains last_op. In the case
515 * of failure getpages_adjacent() clears last_op.
516 *
517 * malloc() may change blocks by calling morecore() only.
518 *
519 * morecore() may create new blocks by:
520 * a) biting pieces from chunk_chain (cannot create one above last_op);
521 * b) biting a piece from an unused block (if block was last_op, this
522 * may create a chunk from chain above last_op, thus last_op is
523 * invalidated in such a case).
524 * c) biting of sbrk()ed-but-not-yet-used space. This creates
525 * a block which is last_op.
526 * d) Allocating new pages by calling getpages();
527 *
528 * getpages() creates a new block. It marks last_op at the bottom of
529 * the chunk of memory it returns.
530 *
531 * Active pages footprint:
532 * ~~~~~~~~~~~~~~~~~~~~~~
533 * Note that we do not need to traverse the lists in nextf[i], just take
534 * the first element of this list. However, we *need* to traverse the
535 * list in chunk_chain, but most the time it should be a very short one,
536 * so we do not step on a lot of pages we are not going to use.
537 *
538 * Flaws:
539 * ~~~~~
540 * get_from_bigger_buckets(): forget to increment price => Quite
541 * aggressive.
542 */
543
544/* I don't much care whether these are defined in sys/types.h--LAW */
545
546#define u_char unsigned char
547#define u_int unsigned int
548/*
549 * I removed the definition of u_bigint which appeared to be u_bigint = UV
550 * u_bigint was only used in TWOK_MASKED and TWOK_SHIFT
551 * where I have used PTR2UV. RMB
552 */
553#define u_short unsigned short
554
555/* 286 and atarist like big chunks, which gives too much overhead. */
556#if (defined(RCHECK) || defined(I286) || defined(atarist) || defined(__MINT__)) && defined(PACK_MALLOC)
557# undef PACK_MALLOC
558#endif
559
560/*
561 * The description below is applicable if PACK_MALLOC is not defined.
562 *
563 * The overhead on a block is at least 4 bytes. When free, this space
564 * contains a pointer to the next free block, and the bottom two bits must
565 * be zero. When in use, the first byte is set to MAGIC, and the second
566 * byte is the size index. The remaining bytes are for alignment.
567 * If range checking is enabled and the size of the block fits
568 * in two bytes, then the top two bytes hold the size of the requested block
569 * plus the range checking words, and the header word MINUS ONE.
570 */
571union overhead {
572 union overhead *ov_next; /* when free */
573#if MEM_ALIGNBYTES > 4
574 double strut; /* alignment problems */
575# if MEM_ALIGNBYTES > 8
576 char sstrut[MEM_ALIGNBYTES]; /* for the sizing */
577# endif
578#endif
579 struct {
580/*
581 * Keep the ovu_index and ovu_magic in this order, having a char
582 * field first gives alignment indigestion in some systems, such as
583 * MachTen.
584 */
585 u_char ovu_index; /* bucket # */
586 u_char ovu_magic; /* magic number */
587#ifdef RCHECK
588 /* Subtract one to fit into u_short for an extra bucket */
589 u_short ovu_size; /* block size (requested + overhead - 1) */
590 u_int ovu_rmagic; /* range magic number */
591#endif
592 } ovu;
593#define ov_magic ovu.ovu_magic
594#define ov_index ovu.ovu_index
595#define ov_size ovu.ovu_size
596#define ov_rmagic ovu.ovu_rmagic
597};
598
599#define MAGIC 0xff /* magic # on accounting info */
600#define RMAGIC 0x55555555 /* magic # on range info */
601#define RMAGIC_C 0x55 /* magic # on range info */
602
603#ifdef RCHECK
604# define RMAGIC_SZ sizeof (u_int) /* Overhead at end of bucket */
605# ifdef TWO_POT_OPTIMIZE
606# define MAX_SHORT_BUCKET (12 * BUCKETS_PER_POW2) /* size-1 fits in short */
607# else
608# define MAX_SHORT_BUCKET (13 * BUCKETS_PER_POW2)
609# endif
610#else
611# define RMAGIC_SZ 0
612#endif
613
614#if !defined(PACK_MALLOC) && defined(BUCKETS_ROOT2)
615# undef BUCKETS_ROOT2
616#endif
617
618#ifdef BUCKETS_ROOT2
619# define BUCKET_TABLE_SHIFT 2
620# define BUCKET_POW2_SHIFT 1
621# define BUCKETS_PER_POW2 2
622#else
623# define BUCKET_TABLE_SHIFT MIN_BUC_POW2
624# define BUCKET_POW2_SHIFT 0
625# define BUCKETS_PER_POW2 1
626#endif
627
628#if !defined(MEM_ALIGNBYTES) || ((MEM_ALIGNBYTES > 4) && !defined(STRICT_ALIGNMENT))
629/* Figure out the alignment of void*. */
630struct aligner {
631 char c;
632 void *p;
633};
634# define ALIGN_SMALL ((int)((caddr_t)&(((struct aligner*)0)->p)))
635#else
636# define ALIGN_SMALL MEM_ALIGNBYTES
637#endif
638
639#define IF_ALIGN_8(yes,no) ((ALIGN_SMALL>4) ? (yes) : (no))
640
641#ifdef BUCKETS_ROOT2
642# define MAX_BUCKET_BY_TABLE 13
643static const u_short buck_size[MAX_BUCKET_BY_TABLE + 1] =
644 {
645 0, 0, 0, 0, 4, 4, 8, 12, 16, 24, 32, 48, 64, 80,
646 };
647# define BUCKET_SIZE_NO_SURPLUS(i) ((i) % 2 ? buck_size[i] : (1 << ((i) >> BUCKET_POW2_SHIFT)))
648# define BUCKET_SIZE_REAL(i) ((i) <= MAX_BUCKET_BY_TABLE \
649 ? buck_size[i] \
650 : ((1 << ((i) >> BUCKET_POW2_SHIFT)) \
651 - MEM_OVERHEAD(i) \
652 + POW2_OPTIMIZE_SURPLUS(i)))
653#else
654# define BUCKET_SIZE_NO_SURPLUS(i) (1 << ((i) >> BUCKET_POW2_SHIFT))
655# define BUCKET_SIZE(i) (BUCKET_SIZE_NO_SURPLUS(i) + POW2_OPTIMIZE_SURPLUS(i))
656# define BUCKET_SIZE_REAL(i) (BUCKET_SIZE(i) - MEM_OVERHEAD(i))
657#endif
658
659
660#ifdef PACK_MALLOC
661/* In this case there are several possible layout of arenas depending
662 * on the size. Arenas are of sizes multiple to 2K, 2K-aligned, and
663 * have a size close to a power of 2.
664 *
665 * Arenas of the size >= 4K keep one chunk only. Arenas of size 2K
666 * may keep one chunk or multiple chunks. Here are the possible
667 * layouts of arenas:
668 *
669 * # One chunk only, chunksize 2^k + SOMETHING - ALIGN, k >= 11
670 *
671 * INDEX MAGIC1 UNUSED CHUNK1
672 *
673 * # Multichunk with sanity checking and chunksize 2^k-ALIGN, k>7
674 *
675 * INDEX MAGIC1 MAGIC2 MAGIC3 UNUSED CHUNK1 CHUNK2 CHUNK3 ...
676 *
677 * # Multichunk with sanity checking and size 2^k-ALIGN, k=7
678 *
679 * INDEX MAGIC1 MAGIC2 MAGIC3 UNUSED CHUNK1 UNUSED CHUNK2 CHUNK3 ...
680 *
681 * # Multichunk with sanity checking and size up to 80
682 *
683 * INDEX UNUSED MAGIC1 UNUSED MAGIC2 UNUSED ... CHUNK1 CHUNK2 CHUNK3 ...
684 *
685 * # No sanity check (usually up to 48=byte-long buckets)
686 * INDEX UNUSED CHUNK1 CHUNK2 ...
687 *
688 * Above INDEX and MAGIC are one-byte-long. Sizes of UNUSED are
689 * appropriate to keep algorithms simple and memory aligned. INDEX
690 * encodes the size of the chunk, while MAGICn encodes state (used,
691 * free or non-managed-by-us-so-it-indicates-a-bug) of CHUNKn. MAGIC
692 * is used for sanity checking purposes only. SOMETHING is 0 or 4K
693 * (to make size of big CHUNK accomodate allocations for powers of two
694 * better).
695 *
696 * [There is no need to alignment between chunks, since C rules ensure
697 * that structs which need 2^k alignment have sizeof which is
698 * divisible by 2^k. Thus as far as the last chunk is aligned at the
699 * end of the arena, and 2K-alignment does not contradict things,
700 * everything is going to be OK for sizes of chunks 2^n and 2^n +
701 * 2^k. Say, 80-bit buckets will be 16-bit aligned, and as far as we
702 * put allocations for requests in 65..80 range, all is fine.
703 *
704 * Note, however, that standard malloc() puts more strict
705 * requirements than the above C rules. Moreover, our algorithms of
706 * realloc() may break this idyll, but we suppose that realloc() does
707 * need not change alignment.]
708 *
709 * Is very important to make calculation of the offset of MAGICm as
710 * quick as possible, since it is done on each malloc()/free(). In
711 * fact it is so quick that it has quite little effect on the speed of
712 * doing malloc()/free(). [By default] We forego such calculations
713 * for small chunks, but only to save extra 3% of memory, not because
714 * of speed considerations.
715 *
716 * Here is the algorithm [which is the same for all the allocations
717 * schemes above], see OV_MAGIC(block,bucket). Let OFFSETm be the
718 * offset of the CHUNKm from the start of ARENA. Then offset of
719 * MAGICm is (OFFSET1 >> SHIFT) + ADDOFFSET. Here SHIFT and ADDOFFSET
720 * are numbers which depend on the size of the chunks only.
721 *
722 * Let as check some sanity conditions. Numbers OFFSETm>>SHIFT are
723 * different for all the chunks in the arena if 2^SHIFT is not greater
724 * than size of the chunks in the arena. MAGIC1 will not overwrite
725 * INDEX provided ADDOFFSET is >0 if OFFSET1 < 2^SHIFT. MAGIClast
726 * will not overwrite CHUNK1 if OFFSET1 > (OFFSETlast >> SHIFT) +
727 * ADDOFFSET.
728 *
729 * Make SHIFT the maximal possible (there is no point in making it
730 * smaller). Since OFFSETlast is 2K - CHUNKSIZE, above restrictions
731 * give restrictions on OFFSET1 and on ADDOFFSET.
732 *
733 * In particular, for chunks of size 2^k with k>=6 we can put
734 * ADDOFFSET to be from 0 to 2^k - 2^(11-k), and have
735 * OFFSET1==chunksize. For chunks of size 80 OFFSET1 of 2K%80=48 is
736 * large enough to have ADDOFFSET between 1 and 16 (similarly for 96,
737 * when ADDOFFSET should be 1). In particular, keeping MAGICs for
738 * these sizes gives no additional size penalty.
739 *
740 * However, for chunks of size 2^k with k<=5 this gives OFFSET1 >=
741 * ADDOFSET + 2^(11-k). Keeping ADDOFFSET 0 allows for 2^(11-k)-2^(11-2k)
742 * chunks per arena. This is smaller than 2^(11-k) - 1 which are
743 * needed if no MAGIC is kept. [In fact, having a negative ADDOFFSET
744 * would allow for slightly more buckets per arena for k=2,3.]
745 *
746 * Similarly, for chunks of size 3/2*2^k with k<=5 MAGICs would span
747 * the area up to 2^(11-k)+ADDOFFSET. For k=4 this give optimal
748 * ADDOFFSET as -7..0. For k=3 ADDOFFSET can go up to 4 (with tiny
749 * savings for negative ADDOFFSET). For k=5 ADDOFFSET can go -1..16
750 * (with no savings for negative values).
751 *
752 * In particular, keeping ADDOFFSET 0 for sizes of chunks up to 2^6
753 * leads to tiny pessimizations in case of sizes 4, 8, 12, 24, and
754 * leads to no contradictions except for size=80 (or 96.)
755 *
756 * However, it also makes sense to keep no magic for sizes 48 or less.
757 * This is what we do. In this case one needs ADDOFFSET>=1 also for
758 * chunksizes 12, 24, and 48, unless one gets one less chunk per
759 * arena.
760 *
761 * The algo of OV_MAGIC(block,bucket) keeps ADDOFFSET 0 until
762 * chunksize of 64, then makes it 1.
763 *
764 * This allows for an additional optimization: the above scheme leads
765 * to giant overheads for sizes 128 or more (one whole chunk needs to
766 * be sacrifised to keep INDEX). Instead we use chunks not of size
767 * 2^k, but of size 2^k-ALIGN. If we pack these chunks at the end of
768 * the arena, then the beginnings are still in different 2^k-long
769 * sections of the arena if k>=7 for ALIGN==4, and k>=8 if ALIGN=8.
770 * Thus for k>7 the above algo of calculating the offset of the magic
771 * will still give different answers for different chunks. And to
772 * avoid the overrun of MAGIC1 into INDEX, one needs ADDOFFSET of >=1.
773 * In the case k=7 we just move the first chunk an extra ALIGN
774 * backward inside the ARENA (this is done once per arena lifetime,
775 * thus is not a big overhead). */
776# define MAX_PACKED_POW2 6
777# define MAX_PACKED (MAX_PACKED_POW2 * BUCKETS_PER_POW2 + BUCKET_POW2_SHIFT)
778# define MAX_POW2_ALGO ((1<<(MAX_PACKED_POW2 + 1)) - M_OVERHEAD)
779# define TWOK_MASK ((1<<LOG_OF_MIN_ARENA) - 1)
780# define TWOK_MASKED(x) (PTR2UV(x) & ~TWOK_MASK)
781# define TWOK_SHIFT(x) (PTR2UV(x) & TWOK_MASK)
782# define OV_INDEXp(block) (INT2PTR(u_char*,TWOK_MASKED(block)))
783# define OV_INDEX(block) (*OV_INDEXp(block))
784# define OV_MAGIC(block,bucket) (*(OV_INDEXp(block) + \
785 (TWOK_SHIFT(block)>> \
786 (bucket>>BUCKET_POW2_SHIFT)) + \
787 (bucket >= MIN_NEEDS_SHIFT ? 1 : 0)))
788 /* A bucket can have a shift smaller than it size, we need to
789 shift its magic number so it will not overwrite index: */
790# ifdef BUCKETS_ROOT2
791# define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2 - 1) /* Shift 80 greater than chunk 64. */
792# else
793# define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2) /* Shift 128 greater than chunk 32. */
794# endif
795# define CHUNK_SHIFT 0
796
797/* Number of active buckets of given ordinal. */
798#ifdef IGNORE_SMALL_BAD_FREE
799#define FIRST_BUCKET_WITH_CHECK (6 * BUCKETS_PER_POW2) /* 64 */
800# define N_BLKS(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \
801 ? ((1<<LOG_OF_MIN_ARENA) - 1)/BUCKET_SIZE_NO_SURPLUS(bucket) \
802 : n_blks[bucket] )
803#else
804# define N_BLKS(bucket) n_blks[bucket]
805#endif
806
807static const u_short n_blks[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] =
808 {
809# if BUCKETS_PER_POW2==1
810 0, 0,
811 (MIN_BUC_POW2==2 ? 384 : 0),
812 224, 120, 62, 31, 16, 8, 4, 2
813# else
814 0, 0, 0, 0,
815 (MIN_BUC_POW2==2 ? 384 : 0), (MIN_BUC_POW2==2 ? 384 : 0), /* 4, 4 */
816 224, 149, 120, 80, 62, 41, 31, 25, 16, 16, 8, 8, 4, 4, 2, 2
817# endif
818 };
819
820/* Shift of the first bucket with the given ordinal inside 2K chunk. */
821#ifdef IGNORE_SMALL_BAD_FREE
822# define BLK_SHIFT(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \
823 ? ((1<<LOG_OF_MIN_ARENA) \
824 - BUCKET_SIZE_NO_SURPLUS(bucket) * N_BLKS(bucket)) \
825 : blk_shift[bucket])
826#else
827# define BLK_SHIFT(bucket) blk_shift[bucket]
828#endif
829
830static const u_short blk_shift[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] =
831 {
832# if BUCKETS_PER_POW2==1
833 0, 0,
834 (MIN_BUC_POW2==2 ? 512 : 0),
835 256, 128, 64, 64, /* 8 to 64 */
836 16*sizeof(union overhead),
837 8*sizeof(union overhead),
838 4*sizeof(union overhead),
839 2*sizeof(union overhead),
840# else
841 0, 0, 0, 0,
842 (MIN_BUC_POW2==2 ? 512 : 0), (MIN_BUC_POW2==2 ? 512 : 0),
843 256, 260, 128, 128, 64, 80, 64, 48, /* 8 to 96 */
844 16*sizeof(union overhead), 16*sizeof(union overhead),
845 8*sizeof(union overhead), 8*sizeof(union overhead),
846 4*sizeof(union overhead), 4*sizeof(union overhead),
847 2*sizeof(union overhead), 2*sizeof(union overhead),
848# endif
849 };
850
851# define NEEDED_ALIGNMENT 0x800 /* 2k boundaries */
852# define WANTED_ALIGNMENT 0x800 /* 2k boundaries */
853
854#else /* !PACK_MALLOC */
855
856# define OV_MAGIC(block,bucket) (block)->ov_magic
857# define OV_INDEX(block) (block)->ov_index
858# define CHUNK_SHIFT 1
859# define MAX_PACKED -1
860# define NEEDED_ALIGNMENT MEM_ALIGNBYTES
861# define WANTED_ALIGNMENT 0x400 /* 1k boundaries */
862
863#endif /* !PACK_MALLOC */
864
865#define M_OVERHEAD (sizeof(union overhead) + RMAGIC_SZ) /* overhead at start+end */
866
867#ifdef PACK_MALLOC
868# define MEM_OVERHEAD(bucket) \
869 (bucket <= MAX_PACKED ? 0 : M_OVERHEAD)
870# ifdef SMALL_BUCKET_VIA_TABLE
871# define START_SHIFTS_BUCKET ((MAX_PACKED_POW2 + 1) * BUCKETS_PER_POW2)
872# define START_SHIFT MAX_PACKED_POW2
873# ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */
874# define SIZE_TABLE_MAX 80
875# else
876# define SIZE_TABLE_MAX 64
877# endif
878static const char bucket_of[] =
879 {
880# ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */
881 /* 0 to 15 in 4-byte increments. */
882 (sizeof(void*) > 4 ? 6 : 5), /* 4/8, 5-th bucket for better reports */
883 6, /* 8 */
884 IF_ALIGN_8(8,7), 8, /* 16/12, 16 */
885 9, 9, 10, 10, /* 24, 32 */
886 11, 11, 11, 11, /* 48 */
887 12, 12, 12, 12, /* 64 */
888 13, 13, 13, 13, /* 80 */
889 13, 13, 13, 13 /* 80 */
890# else /* !BUCKETS_ROOT2 */
891 /* 0 to 15 in 4-byte increments. */
892 (sizeof(void*) > 4 ? 3 : 2),
893 3,
894 4, 4,
895 5, 5, 5, 5,
896 6, 6, 6, 6,
897 6, 6, 6, 6
898# endif /* !BUCKETS_ROOT2 */
899 };
900# else /* !SMALL_BUCKET_VIA_TABLE */
901# define START_SHIFTS_BUCKET MIN_BUCKET
902# define START_SHIFT (MIN_BUC_POW2 - 1)
903# endif /* !SMALL_BUCKET_VIA_TABLE */
904#else /* !PACK_MALLOC */
905# define MEM_OVERHEAD(bucket) M_OVERHEAD
906# ifdef SMALL_BUCKET_VIA_TABLE
907# undef SMALL_BUCKET_VIA_TABLE
908# endif
909# define START_SHIFTS_BUCKET MIN_BUCKET
910# define START_SHIFT (MIN_BUC_POW2 - 1)
911#endif /* !PACK_MALLOC */
912
913/*
914 * Big allocations are often of the size 2^n bytes. To make them a
915 * little bit better, make blocks of size 2^n+pagesize for big n.
916 */
917
918#ifdef TWO_POT_OPTIMIZE
919
920# ifndef PERL_PAGESIZE
921# define PERL_PAGESIZE 4096
922# endif
923# ifndef FIRST_BIG_POW2
924# define FIRST_BIG_POW2 15 /* 32K, 16K is used too often. */
925# endif
926# define FIRST_BIG_BLOCK (1<<FIRST_BIG_POW2)
927/* If this value or more, check against bigger blocks. */
928# define FIRST_BIG_BOUND (FIRST_BIG_BLOCK - M_OVERHEAD)
929/* If less than this value, goes into 2^n-overhead-block. */
930# define LAST_SMALL_BOUND ((FIRST_BIG_BLOCK>>1) - M_OVERHEAD)
931
932# define POW2_OPTIMIZE_ADJUST(nbytes) \
933 ((nbytes >= FIRST_BIG_BOUND) ? nbytes -= PERL_PAGESIZE : 0)
934# define POW2_OPTIMIZE_SURPLUS(bucket) \
935 ((bucket >= FIRST_BIG_POW2 * BUCKETS_PER_POW2) ? PERL_PAGESIZE : 0)
936
937#else /* !TWO_POT_OPTIMIZE */
938# define POW2_OPTIMIZE_ADJUST(nbytes)
939# define POW2_OPTIMIZE_SURPLUS(bucket) 0
940#endif /* !TWO_POT_OPTIMIZE */
941
942#if defined(HAS_64K_LIMIT) && defined(PERL_CORE)
943# define BARK_64K_LIMIT(what,nbytes,size) \
944 if (nbytes > 0xffff) { \
945 PerlIO_printf(PerlIO_stderr(), \
946 "%s too large: %lx\n", what, size); \
947 my_exit(1); \
948 }
949#else /* !HAS_64K_LIMIT || !PERL_CORE */
950# define BARK_64K_LIMIT(what,nbytes,size)
951#endif /* !HAS_64K_LIMIT || !PERL_CORE */
952
953#ifndef MIN_SBRK
954# define MIN_SBRK 2048
955#endif
956
957#ifndef FIRST_SBRK
958# define FIRST_SBRK (48*1024)
959#endif
960
961/* Minimal sbrk in percents of what is already alloced. */
962#ifndef MIN_SBRK_FRAC
963# define MIN_SBRK_FRAC 3
964#endif
965
966#ifndef SBRK_ALLOW_FAILURES
967# define SBRK_ALLOW_FAILURES 3
968#endif
969
970#ifndef SBRK_FAILURE_PRICE
971# define SBRK_FAILURE_PRICE 50
972#endif
973
974static void morecore (register int bucket);
975# if defined(DEBUGGING)
976static void botch (char *diag, char *s, char *file, int line);
977# endif
978static void add_to_chain (void *p, MEM_SIZE size, MEM_SIZE chip);
979static void* get_from_chain (MEM_SIZE size);
980static void* get_from_bigger_buckets(int bucket, MEM_SIZE size);
981static union overhead *getpages (MEM_SIZE needed, int *nblksp, int bucket);
982static int getpages_adjacent(MEM_SIZE require);
983
984#ifdef PERL_CORE
985
986#ifdef I_MACH_CTHREADS
987# undef MUTEX_LOCK
988# define MUTEX_LOCK(m) STMT_START { if (*m) mutex_lock(*m); } STMT_END
989# undef MUTEX_UNLOCK
990# define MUTEX_UNLOCK(m) STMT_START { if (*m) mutex_unlock(*m); } STMT_END
991#endif
992
993#endif /* defined PERL_CORE */
994
995#ifndef PTRSIZE
996# define PTRSIZE sizeof(void*)
997#endif
998
999#ifndef BITS_IN_PTR
1000# define BITS_IN_PTR (8*PTRSIZE)
1001#endif
1002
1003/*
1004 * nextf[i] is the pointer to the next free block of size 2^i. The
1005 * smallest allocatable block is 8 bytes. The overhead information
1006 * precedes the data area returned to the user.
1007 */
1008#define NBUCKETS (BITS_IN_PTR*BUCKETS_PER_POW2 + 1)
1009static union overhead *nextf[NBUCKETS];
1010
1011#if defined(PURIFY) && !defined(USE_PERL_SBRK)
1012# define USE_PERL_SBRK
1013#endif
1014
1015#ifdef USE_PERL_SBRK
1016# define sbrk(a) Perl_sbrk(a)
1017Malloc_t Perl_sbrk (int size);
1018#else
1019# ifndef HAS_SBRK_PROTO /* <unistd.h> usually takes care of this */
1020extern Malloc_t sbrk(int);
1021# endif
1022#endif
1023
1024#ifndef MIN_SBRK_FRAC1000 /* Backward compatibility */
1025# define MIN_SBRK_FRAC1000 (MIN_SBRK_FRAC * 10)
1026#endif
1027
1028#ifndef START_EXTERN_C
1029# ifdef __cplusplus
1030# define START_EXTERN_C extern "C" {
1031# else
1032# define START_EXTERN_C
1033# endif
1034#endif
1035
1036#ifndef END_EXTERN_C
1037# ifdef __cplusplus
1038# define END_EXTERN_C };
1039# else
1040# define END_EXTERN_C
1041# endif
1042#endif
1043
1044#include "malloc_ctl.h"
1045
1046#ifndef NO_MALLOC_DYNAMIC_CFG
1047# define PERL_MALLOC_OPT_CHARS "FMfAPGdac"
1048
1049# ifndef FILL_DEAD_DEFAULT
1050# define FILL_DEAD_DEFAULT 1
1051# endif
1052# ifndef FILL_ALIVE_DEFAULT
1053# define FILL_ALIVE_DEFAULT 1
1054# endif
1055# ifndef FILL_CHECK_DEFAULT
1056# define FILL_CHECK_DEFAULT 1
1057# endif
1058
1059static IV MallocCfg[MallocCfg_last] = {
1060 FIRST_SBRK,
1061 MIN_SBRK,
1062 MIN_SBRK_FRAC,
1063 SBRK_ALLOW_FAILURES,
1064 SBRK_FAILURE_PRICE,
1065 SBRK_ALLOW_FAILURES * SBRK_FAILURE_PRICE, /* sbrk_goodness */
1066 FILL_DEAD_DEFAULT, /* FILL_DEAD */
1067 FILL_ALIVE_DEFAULT, /* FILL_ALIVE */
1068 FILL_CHECK_DEFAULT, /* FILL_CHECK */
1069 0, /* MallocCfg_skip_cfg_env */
1070 0, /* MallocCfg_cfg_env_read */
1071 0, /* MallocCfg_emergency_buffer_size */
1072 0, /* MallocCfg_emergency_buffer_prepared_size */
1073 0 /* MallocCfg_emergency_buffer_last_req */
1074};
1075IV *MallocCfg_ptr = MallocCfg;
1076
1077static char* MallocCfgP[MallocCfg_last] = {
1078 0, /* MallocCfgP_emergency_buffer */
1079 0, /* MallocCfgP_emergency_buffer_prepared */
1080};
1081char **MallocCfgP_ptr = MallocCfgP;
1082
1083# undef MIN_SBRK
1084# undef FIRST_SBRK
1085# undef MIN_SBRK_FRAC1000
1086# undef SBRK_ALLOW_FAILURES
1087# undef SBRK_FAILURE_PRICE
1088
1089# define MIN_SBRK MallocCfg[MallocCfg_MIN_SBRK]
1090# define FIRST_SBRK MallocCfg[MallocCfg_FIRST_SBRK]
1091# define MIN_SBRK_FRAC1000 MallocCfg[MallocCfg_MIN_SBRK_FRAC1000]
1092# define SBRK_ALLOW_FAILURES MallocCfg[MallocCfg_SBRK_ALLOW_FAILURES]
1093# define SBRK_FAILURE_PRICE MallocCfg[MallocCfg_SBRK_FAILURE_PRICE]
1094
1095# define sbrk_goodness MallocCfg[MallocCfg_sbrk_goodness]
1096
1097# define emergency_buffer_size MallocCfg[MallocCfg_emergency_buffer_size]
1098# define emergency_buffer_last_req MallocCfg[MallocCfg_emergency_buffer_last_req]
1099
1100# define FILL_DEAD MallocCfg[MallocCfg_filldead]
1101# define FILL_ALIVE MallocCfg[MallocCfg_fillalive]
1102# define FILL_CHECK_CFG MallocCfg[MallocCfg_fillcheck]
1103# define FILL_CHECK (FILL_DEAD && FILL_CHECK_CFG)
1104
1105# define emergency_buffer MallocCfgP[MallocCfgP_emergency_buffer]
1106# define emergency_buffer_prepared MallocCfgP[MallocCfgP_emergency_buffer_prepared]
1107
1108#else /* defined(NO_MALLOC_DYNAMIC_CFG) */
1109
1110# define FILL_DEAD 1
1111# define FILL_ALIVE 1
1112# define FILL_CHECK 1
1113static int sbrk_goodness = SBRK_ALLOW_FAILURES * SBRK_FAILURE_PRICE;
1114
1115# define NO_PERL_MALLOC_ENV
1116
1117#endif
1118
1119#ifdef DEBUGGING_MSTATS
1120/*
1121 * nmalloc[i] is the difference between the number of mallocs and frees
1122 * for a given block size.
1123 */
1124static u_int nmalloc[NBUCKETS];
1125static u_int sbrk_slack;
1126static u_int start_slack;
1127#else /* !( defined DEBUGGING_MSTATS ) */
1128# define sbrk_slack 0
1129#endif
1130
1131static u_int goodsbrk;
1132
1133#ifdef PERL_EMERGENCY_SBRK
1134
1135# ifndef BIG_SIZE
1136# define BIG_SIZE (1<<16) /* 64K */
1137# endif
1138
1139# ifdef NO_MALLOC_DYNAMIC_CFG
1140static MEM_SIZE emergency_buffer_size;
1141 /* 0 if the last request for more memory succeeded.
1142 Otherwise the size of the failing request. */
1143static MEM_SIZE emergency_buffer_last_req;
1144static char *emergency_buffer;
1145static char *emergency_buffer_prepared;
1146# endif
1147
1148# ifndef emergency_sbrk_croak
1149# define emergency_sbrk_croak croak2
1150# endif
1151
1152# ifdef PERL_CORE
1153static char *
1154perl_get_emergency_buffer(IV *size)
1155{
1156 dTHX;
1157 /* First offense, give a possibility to recover by dieing. */
1158 /* No malloc involved here: */
1159 GV **gvp = (GV**)hv_fetch(PL_defstash, "^M", 2, 0);
1160 SV *sv;
1161 char *pv;
1162
1163 if (!gvp) gvp = (GV**)hv_fetch(PL_defstash, "\015", 1, 0);
1164 if (!gvp || !(sv = GvSV(*gvp)) || !SvPOK(sv)
1165 || (SvLEN(sv) < (1<<LOG_OF_MIN_ARENA) - M_OVERHEAD))
1166 return NULL; /* Now die die die... */
1167 /* Got it, now detach SvPV: */
1168 pv = SvPV_nolen(sv);
1169 /* Check alignment: */
1170 if ((PTR2UV(pv) - sizeof(union overhead)) & (NEEDED_ALIGNMENT - 1)) {
1171 PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n");
1172 return NULL; /* die die die */
1173 }
1174
1175 SvPOK_off(sv);
1176 SvPV_set(sv, Nullch);
1177 SvCUR_set(sv, 0);
1178 SvLEN_set(sv, 0);
1179 *size = malloced_size(pv) + M_OVERHEAD;
1180 return pv - sizeof(union overhead);
1181}
1182# define PERL_GET_EMERGENCY_BUFFER(p) perl_get_emergency_buffer(p)
1183# else
1184# define PERL_GET_EMERGENCY_BUFFER(p) NULL
1185# endif /* defined PERL_CORE */
1186
1187# ifndef NO_MALLOC_DYNAMIC_CFG
1188static char *
1189get_emergency_buffer(IV *size)
1190{
1191 char *pv = emergency_buffer_prepared;
1192
1193 *size = MallocCfg[MallocCfg_emergency_buffer_prepared_size];
1194 emergency_buffer_prepared = 0;
1195 MallocCfg[MallocCfg_emergency_buffer_prepared_size] = 0;
1196 return pv;
1197}
1198
1199/* Returns 0 on success, -1 on bad alignment, -2 if not implemented */
1200int
1201set_emergency_buffer(char *b, IV size)
1202{
1203 if (PTR2UV(b) & (NEEDED_ALIGNMENT - 1))
1204 return -1;
1205 if (MallocCfg[MallocCfg_emergency_buffer_prepared_size])
1206 add_to_chain((void*)emergency_buffer_prepared,
1207 MallocCfg[MallocCfg_emergency_buffer_prepared_size], 0);
1208 emergency_buffer_prepared = b;
1209 MallocCfg[MallocCfg_emergency_buffer_prepared_size] = size;
1210 return 0;
1211}
1212# define GET_EMERGENCY_BUFFER(p) get_emergency_buffer(p)
1213# else /* NO_MALLOC_DYNAMIC_CFG */
1214# define GET_EMERGENCY_BUFFER(p) NULL
1215int
1216set_emergency_buffer(char *b, IV size)
1217{
1218 return -1;
1219}
1220# endif
1221
1222static Malloc_t
1223emergency_sbrk(MEM_SIZE size)
1224{
1225 MEM_SIZE rsize = (((size - 1)>>LOG_OF_MIN_ARENA) + 1)<<LOG_OF_MIN_ARENA;
1226
1227 if (size >= BIG_SIZE
1228 && (!emergency_buffer_last_req ||
1229 (size < (MEM_SIZE)emergency_buffer_last_req))) {
1230 /* Give the possibility to recover, but avoid an infinite cycle. */
1231 MALLOC_UNLOCK;
1232 emergency_buffer_last_req = size;
1233 emergency_sbrk_croak("Out of memory during \"large\" request for %"UVuf" bytes, total sbrk() is %"UVuf" bytes", (UV)size, (UV)(goodsbrk + sbrk_slack));
1234 }
1235
1236 if ((MEM_SIZE)emergency_buffer_size >= rsize) {
1237 char *old = emergency_buffer;
1238
1239 emergency_buffer_size -= rsize;
1240 emergency_buffer += rsize;
1241 return old;
1242 } else {
1243 /* First offense, give a possibility to recover by dieing. */
1244 /* No malloc involved here: */
1245 IV Size;
1246 char *pv = GET_EMERGENCY_BUFFER(&Size);
1247 int have = 0;
1248
1249 if (emergency_buffer_size) {
1250 add_to_chain(emergency_buffer, emergency_buffer_size, 0);
1251 emergency_buffer_size = 0;
1252 emergency_buffer = Nullch;
1253 have = 1;
1254 }
1255
1256 if (!pv)
1257 pv = PERL_GET_EMERGENCY_BUFFER(&Size);
1258 if (!pv) {
1259 if (have)
1260 goto do_croak;
1261 return (char *)-1; /* Now die die die... */
1262 }
1263
1264 /* Check alignment: */
1265 if (PTR2UV(pv) & (NEEDED_ALIGNMENT - 1)) {
1266 dTHX;
1267
1268 PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n");
1269 return (char *)-1; /* die die die */
1270 }
1271
1272 emergency_buffer = pv;
1273 emergency_buffer_size = Size;
1274 }
1275 do_croak:
1276 MALLOC_UNLOCK;
1277 emergency_sbrk_croak("Out of memory during request for %"UVuf" bytes, total sbrk() is %"UVuf" bytes", (UV)size, (UV)(goodsbrk + sbrk_slack));
1278 /* NOTREACHED */
1279 return Nullch;
1280}
1281
1282#else /* !defined(PERL_EMERGENCY_SBRK) */
1283# define emergency_sbrk(size) -1
1284#endif /* defined PERL_EMERGENCY_SBRK */
1285
1286static void
1287write2(char *mess)
1288{
1289 write(2, mess, strlen(mess));
1290}
1291
1292#ifdef DEBUGGING
1293#undef ASSERT
1294#define ASSERT(p,diag) if (!(p)) botch(diag,STRINGIFY(p),__FILE__,__LINE__); else
1295static void
1296botch(char *diag, char *s, char *file, int line)
1297{
1298 if (!(PERL_MAYBE_ALIVE && PERL_GET_THX))
1299 goto do_write;
1300 else {
1301 dTHX;
1302 if (PerlIO_printf(PerlIO_stderr(),
1303 "assertion botched (%s?): %s %s:%d\n",
1304 diag, s, file, line) != 0) {
1305 do_write: /* Can be initializing interpreter */
1306 write2("assertion botched (");
1307 write2(diag);
1308 write2("?): ");
1309 write2(s);
1310 write2(" (");
1311 write2(file);
1312 write2(":");
1313 {
1314 char linebuf[10];
1315 char *s = linebuf + sizeof(linebuf) - 1;
1316 int n = line;
1317 *s = 0;
1318 do {
1319 *--s = '0' + (n % 10);
1320 } while (n /= 10);
1321 write2(s);
1322 }
1323 write2(")\n");
1324 }
1325 PerlProc_abort();
1326 }
1327}
1328#else
1329#define ASSERT(p, diag)
1330#endif
1331
1332#ifdef MALLOC_FILL
1333/* Fill should be long enough to cover long */
1334static void
1335fill_pat_4bytes(unsigned char *s, size_t nbytes, const unsigned char *fill)
1336{
1337 unsigned char *e = s + nbytes;
1338 long *lp;
1339 const long lfill = *(long*)fill;
1340
1341 if (PTR2UV(s) & (sizeof(long)-1)) { /* Align the pattern */
1342 int shift = sizeof(long) - (PTR2UV(s) & (sizeof(long)-1));
1343 unsigned const char *f = fill + sizeof(long) - shift;
1344 unsigned char *e1 = s + shift;
1345
1346 while (s < e1)
1347 *s++ = *f++;
1348 }
1349 lp = (long*)s;
1350 while ((unsigned char*)(lp + 1) <= e)
1351 *lp++ = lfill;
1352 s = (unsigned char*)lp;
1353 while (s < e)
1354 *s++ = *fill++;
1355}
1356/* Just malloc()ed */
1357static const unsigned char fill_feedadad[] =
1358 {0xFE, 0xED, 0xAD, 0xAD, 0xFE, 0xED, 0xAD, 0xAD,
1359 0xFE, 0xED, 0xAD, 0xAD, 0xFE, 0xED, 0xAD, 0xAD};
1360/* Just free()ed */
1361static const unsigned char fill_deadbeef[] =
1362 {0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF,
1363 0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF};
1364# define FILL_DEADBEEF(s, n) \
1365 (void)(FILL_DEAD? (fill_pat_4bytes((s), (n), fill_deadbeef), 0) : 0)
1366# define FILL_FEEDADAD(s, n) \
1367 (void)(FILL_ALIVE? (fill_pat_4bytes((s), (n), fill_feedadad), 0) : 0)
1368#else
1369# define FILL_DEADBEEF(s, n) ((void)0)
1370# define FILL_FEEDADAD(s, n) ((void)0)
1371# undef MALLOC_FILL_CHECK
1372#endif
1373
1374#ifdef MALLOC_FILL_CHECK
1375static int
1376cmp_pat_4bytes(unsigned char *s, size_t nbytes, const unsigned char *fill)
1377{
1378 unsigned char *e = s + nbytes;
1379 long *lp;
1380 const long lfill = *(long*)fill;
1381
1382 if (PTR2UV(s) & (sizeof(long)-1)) { /* Align the pattern */
1383 int shift = sizeof(long) - (PTR2UV(s) & (sizeof(long)-1));
1384 unsigned const char *f = fill + sizeof(long) - shift;
1385 unsigned char *e1 = s + shift;
1386
1387 while (s < e1)
1388 if (*s++ != *f++)
1389 return 1;
1390 }
1391 lp = (long*)s;
1392 while ((unsigned char*)(lp + 1) <= e)
1393 if (*lp++ != lfill)
1394 return 1;
1395 s = (unsigned char*)lp;
1396 while (s < e)
1397 if (*s++ != *fill++)
1398 return 1;
1399 return 0;
1400}
1401# define FILLCHECK_DEADBEEF(s, n) \
1402 ASSERT(!FILL_CHECK || !cmp_pat_4bytes(s, n, fill_deadbeef), \
1403 "free()ed/realloc()ed-away memory was overwritten")
1404#else
1405# define FILLCHECK_DEADBEEF(s, n) ((void)0)
1406#endif
1407
1408Malloc_t
1409Perl_malloc(register size_t nbytes)
1410{
1411 register union overhead *p;
1412 register int bucket;
1413 register MEM_SIZE shiftr;
1414
1415#if defined(DEBUGGING) || defined(RCHECK)
1416 MEM_SIZE size = nbytes;
1417#endif
1418
1419 BARK_64K_LIMIT("Allocation",nbytes,nbytes);
1420#ifdef DEBUGGING
1421 if ((long)nbytes < 0)
1422 croak("%s", "panic: malloc");
1423#endif
1424
1425 /*
1426 * Convert amount of memory requested into
1427 * closest block size stored in hash buckets
1428 * which satisfies request. Account for
1429 * space used per block for accounting.
1430 */
1431#ifdef PACK_MALLOC
1432# ifdef SMALL_BUCKET_VIA_TABLE
1433 if (nbytes == 0)
1434 bucket = MIN_BUCKET;
1435 else if (nbytes <= SIZE_TABLE_MAX) {
1436 bucket = bucket_of[(nbytes - 1) >> BUCKET_TABLE_SHIFT];
1437 } else
1438# else
1439 if (nbytes == 0)
1440 nbytes = 1;
1441 if (nbytes <= MAX_POW2_ALGO) goto do_shifts;
1442 else
1443# endif
1444#endif
1445 {
1446 POW2_OPTIMIZE_ADJUST(nbytes);
1447 nbytes += M_OVERHEAD;
1448 nbytes = (nbytes + 3) &~ 3;
1449#if defined(PACK_MALLOC) && !defined(SMALL_BUCKET_VIA_TABLE)
1450 do_shifts:
1451#endif
1452 shiftr = (nbytes - 1) >> START_SHIFT;
1453 bucket = START_SHIFTS_BUCKET;
1454 /* apart from this loop, this is O(1) */
1455 while (shiftr >>= 1)
1456 bucket += BUCKETS_PER_POW2;
1457 }
1458 MALLOC_LOCK;
1459 /*
1460 * If nothing in hash bucket right now,
1461 * request more memory from the system.
1462 */
1463 if (nextf[bucket] == NULL)
1464 morecore(bucket);
1465 if ((p = nextf[bucket]) == NULL) {
1466 MALLOC_UNLOCK;
1467#ifdef PERL_CORE
1468 {
1469 dTHX;
1470 if (!PL_nomemok) {
1471#if defined(PLAIN_MALLOC) && defined(NO_FANCY_MALLOC)
1472 PerlIO_puts(PerlIO_stderr(),"Out of memory!\n");
1473#else
1474 char buff[80];
1475 char *eb = buff + sizeof(buff) - 1;
1476 char *s = eb;
1477 size_t n = nbytes;
1478
1479 PerlIO_puts(PerlIO_stderr(),"Out of memory during request for ");
1480#if defined(DEBUGGING) || defined(RCHECK)
1481 n = size;
1482#endif
1483 *s = 0;
1484 do {
1485 *--s = '0' + (n % 10);
1486 } while (n /= 10);
1487 PerlIO_puts(PerlIO_stderr(),s);
1488 PerlIO_puts(PerlIO_stderr()," bytes, total sbrk() is ");
1489 s = eb;
1490 n = goodsbrk + sbrk_slack;
1491 do {
1492 *--s = '0' + (n % 10);
1493 } while (n /= 10);
1494 PerlIO_puts(PerlIO_stderr(),s);
1495 PerlIO_puts(PerlIO_stderr()," bytes!\n");
1496#endif /* defined(PLAIN_MALLOC) && defined(NO_FANCY_MALLOC) */
1497 my_exit(1);
1498 }
1499 }
1500#endif
1501 return (NULL);
1502 }
1503
1504 /* remove from linked list */
1505#ifdef DEBUGGING
1506 if ( (PTR2UV(p) & (MEM_ALIGNBYTES - 1))
1507 /* Can't get this low */
1508 || (p && PTR2UV(p) < (1<<LOG_OF_MIN_ARENA)) ) {
1509 dTHX;
1510 PerlIO_printf(PerlIO_stderr(),
1511 "Unaligned pointer in the free chain 0x%"UVxf"\n",
1512 PTR2UV(p));
1513 }
1514 if ( (PTR2UV(p->ov_next) & (MEM_ALIGNBYTES - 1))
1515 || (p->ov_next && PTR2UV(p->ov_next) < (1<<LOG_OF_MIN_ARENA)) ) {
1516 dTHX;
1517 PerlIO_printf(PerlIO_stderr(),
1518 "Unaligned \"next\" pointer in the free "
1519 "chain 0x%"UVxf" at 0x%"UVxf"\n",
1520 PTR2UV(p->ov_next), PTR2UV(p));
1521 }
1522#endif
1523 nextf[bucket] = p->ov_next;
1524
1525 MALLOC_UNLOCK;
1526
1527 DEBUG_m(PerlIO_printf(Perl_debug_log,
1528 "0x%"UVxf": (%05lu) malloc %ld bytes\n",
1529 PTR2UV((Malloc_t)(p + CHUNK_SHIFT)), (unsigned long)(PL_an++),
1530 (long)size));
1531
1532 FILLCHECK_DEADBEEF((unsigned char*)(p + CHUNK_SHIFT),
1533 BUCKET_SIZE_REAL(bucket) + RMAGIC_SZ);
1534
1535#ifdef IGNORE_SMALL_BAD_FREE
1536 if (bucket >= FIRST_BUCKET_WITH_CHECK)
1537#endif
1538 OV_MAGIC(p, bucket) = MAGIC;
1539#ifndef PACK_MALLOC
1540 OV_INDEX(p) = bucket;
1541#endif
1542#ifdef RCHECK
1543 /*
1544 * Record allocated size of block and
1545 * bound space with magic numbers.
1546 */
1547 p->ov_rmagic = RMAGIC;
1548 if (bucket <= MAX_SHORT_BUCKET) {
1549 int i;
1550
1551 nbytes = size + M_OVERHEAD;
1552 p->ov_size = nbytes - 1;
1553 if ((i = nbytes & (RMAGIC_SZ-1))) {
1554 i = RMAGIC_SZ - i;
1555 while (i--) /* nbytes - RMAGIC_SZ is end of alloced area */
1556 ((caddr_t)p + nbytes - RMAGIC_SZ)[i] = RMAGIC_C;
1557 }
1558 /* Same at RMAGIC_SZ-aligned RMAGIC */
1559 nbytes = (nbytes + RMAGIC_SZ - 1) & ~(RMAGIC_SZ - 1);
1560 ((u_int *)((caddr_t)p + nbytes))[-1] = RMAGIC;
1561 }
1562 FILL_FEEDADAD((unsigned char *)(p + CHUNK_SHIFT), size);
1563#endif
1564 return ((Malloc_t)(p + CHUNK_SHIFT));
1565}
1566
1567static char *last_sbrk_top;
1568static char *last_op; /* This arena can be easily extended. */
1569static MEM_SIZE sbrked_remains;
1570
1571#ifdef DEBUGGING_MSTATS
1572static int sbrks;
1573#endif
1574
1575struct chunk_chain_s {
1576 struct chunk_chain_s *next;
1577 MEM_SIZE size;
1578};
1579static struct chunk_chain_s *chunk_chain;
1580static int n_chunks;
1581static char max_bucket;
1582
1583/* Cutoff a piece of one of the chunks in the chain. Prefer smaller chunk. */
1584static void *
1585get_from_chain(MEM_SIZE size)
1586{
1587 struct chunk_chain_s *elt = chunk_chain, **oldp = &chunk_chain;
1588 struct chunk_chain_s **oldgoodp = NULL;
1589 long min_remain = LONG_MAX;
1590
1591 while (elt) {
1592 if (elt->size >= size) {
1593 long remains = elt->size - size;
1594 if (remains >= 0 && remains < min_remain) {
1595 oldgoodp = oldp;
1596 min_remain = remains;
1597 }
1598 if (remains == 0) {
1599 break;
1600 }
1601 }
1602 oldp = &( elt->next );
1603 elt = elt->next;
1604 }
1605 if (!oldgoodp) return NULL;
1606 if (min_remain) {
1607 void *ret = *oldgoodp;
1608 struct chunk_chain_s *next = (*oldgoodp)->next;
1609
1610 *oldgoodp = (struct chunk_chain_s *)((char*)ret + size);
1611 (*oldgoodp)->size = min_remain;
1612 (*oldgoodp)->next = next;
1613 return ret;
1614 } else {
1615 void *ret = *oldgoodp;
1616 *oldgoodp = (*oldgoodp)->next;
1617 n_chunks--;
1618 return ret;
1619 }
1620}
1621
1622static void
1623add_to_chain(void *p, MEM_SIZE size, MEM_SIZE chip)
1624{
1625 struct chunk_chain_s *next = chunk_chain;
1626 char *cp = (char*)p;
1627
1628 cp += chip;
1629 chunk_chain = (struct chunk_chain_s *)cp;
1630 chunk_chain->size = size - chip;
1631 chunk_chain->next = next;
1632 n_chunks++;
1633}
1634
1635static void *
1636get_from_bigger_buckets(int bucket, MEM_SIZE size)
1637{
1638 int price = 1;
1639 static int bucketprice[NBUCKETS];
1640 while (bucket <= max_bucket) {
1641 /* We postpone stealing from bigger buckets until we want it
1642 often enough. */
1643 if (nextf[bucket] && bucketprice[bucket]++ >= price) {
1644 /* Steal it! */
1645 void *ret = (void*)(nextf[bucket] - 1 + CHUNK_SHIFT);
1646 bucketprice[bucket] = 0;
1647 if (((char*)nextf[bucket]) - M_OVERHEAD == last_op) {
1648 last_op = NULL; /* Disable optimization */
1649 }
1650 nextf[bucket] = nextf[bucket]->ov_next;
1651#ifdef DEBUGGING_MSTATS
1652 nmalloc[bucket]--;
1653 start_slack -= M_OVERHEAD;
1654#endif
1655 add_to_chain(ret, (BUCKET_SIZE_NO_SURPLUS(bucket) +
1656 POW2_OPTIMIZE_SURPLUS(bucket)),
1657 size);
1658 return ret;
1659 }
1660 bucket++;
1661 }
1662 return NULL;
1663}
1664
1665static union overhead *
1666getpages(MEM_SIZE needed, int *nblksp, int bucket)
1667{
1668 /* Need to do (possibly expensive) system call. Try to
1669 optimize it for rare calling. */
1670 MEM_SIZE require = needed - sbrked_remains;
1671 char *cp;
1672 union overhead *ovp;
1673 MEM_SIZE slack = 0;
1674
1675 if (sbrk_goodness > 0) {
1676 if (!last_sbrk_top && require < (MEM_SIZE)FIRST_SBRK)
1677 require = FIRST_SBRK;
1678 else if (require < (MEM_SIZE)MIN_SBRK) require = MIN_SBRK;
1679
1680 if (require < goodsbrk * MIN_SBRK_FRAC1000 / 1000)
1681 require = goodsbrk * MIN_SBRK_FRAC1000 / 1000;
1682 require = ((require - 1 + MIN_SBRK) / MIN_SBRK) * MIN_SBRK;
1683 } else {
1684 require = needed;
1685 last_sbrk_top = 0;
1686 sbrked_remains = 0;
1687 }
1688
1689 DEBUG_m(PerlIO_printf(Perl_debug_log,
1690 "sbrk(%ld) for %ld-byte-long arena\n",
1691 (long)require, (long) needed));
1692 cp = (char *)sbrk(require);
1693#ifdef DEBUGGING_MSTATS
1694 sbrks++;
1695#endif
1696 if (cp == last_sbrk_top) {
1697 /* Common case, anything is fine. */
1698 sbrk_goodness++;
1699 ovp = (union overhead *) (cp - sbrked_remains);
1700 last_op = cp - sbrked_remains;
1701 sbrked_remains = require - (needed - sbrked_remains);
1702 } else if (cp == (char *)-1) { /* no more room! */
1703 ovp = (union overhead *)emergency_sbrk(needed);
1704 if (ovp == (union overhead *)-1)
1705 return 0;
1706 if (((char*)ovp) > last_op) { /* Cannot happen with current emergency_sbrk() */
1707 last_op = 0;
1708 }
1709 return ovp;
1710 } else { /* Non-continuous or first sbrk(). */
1711 long add = sbrked_remains;
1712 char *newcp;
1713
1714 if (sbrked_remains) { /* Put rest into chain, we
1715 cannot use it right now. */
1716 add_to_chain((void*)(last_sbrk_top - sbrked_remains),
1717 sbrked_remains, 0);
1718 }
1719
1720 /* Second, check alignment. */
1721 slack = 0;
1722
1723#if !defined(atarist) && !defined(__MINT__) /* on the atari we dont have to worry about this */
1724# ifndef I286 /* The sbrk(0) call on the I286 always returns the next segment */
1725 /* WANTED_ALIGNMENT may be more than NEEDED_ALIGNMENT, but this may
1726 improve performance of memory access. */
1727 if (PTR2UV(cp) & (WANTED_ALIGNMENT - 1)) { /* Not aligned. */
1728 slack = WANTED_ALIGNMENT - (PTR2UV(cp) & (WANTED_ALIGNMENT - 1));
1729 add += slack;
1730 }
1731# endif
1732#endif /* !atarist && !MINT */
1733
1734 if (add) {
1735 DEBUG_m(PerlIO_printf(Perl_debug_log,
1736 "sbrk(%ld) to fix non-continuous/off-page sbrk:\n\t%ld for alignement,\t%ld were assumed to come from the tail of the previous sbrk\n",
1737 (long)add, (long) slack,
1738 (long) sbrked_remains));
1739 newcp = (char *)sbrk(add);
1740#if defined(DEBUGGING_MSTATS)
1741 sbrks++;
1742 sbrk_slack += add;
1743#endif
1744 if (newcp != cp + require) {
1745 /* Too bad: even rounding sbrk() is not continuous.*/
1746 DEBUG_m(PerlIO_printf(Perl_debug_log,
1747 "failed to fix bad sbrk()\n"));
1748#ifdef PACK_MALLOC
1749 if (slack) {
1750 MALLOC_UNLOCK;
1751 fatalcroak("panic: Off-page sbrk\n");
1752 }
1753#endif
1754 if (sbrked_remains) {
1755 /* Try again. */
1756#if defined(DEBUGGING_MSTATS)
1757 sbrk_slack += require;
1758#endif
1759 require = needed;
1760 DEBUG_m(PerlIO_printf(Perl_debug_log,
1761 "straight sbrk(%ld)\n",
1762 (long)require));
1763 cp = (char *)sbrk(require);
1764#ifdef DEBUGGING_MSTATS
1765 sbrks++;
1766#endif
1767 if (cp == (char *)-1)
1768 return 0;
1769 }
1770 sbrk_goodness = -1; /* Disable optimization!
1771 Continue with not-aligned... */
1772 } else {
1773 cp += slack;
1774 require += sbrked_remains;
1775 }
1776 }
1777
1778 if (last_sbrk_top) {
1779 sbrk_goodness -= SBRK_FAILURE_PRICE;
1780 }
1781
1782 ovp = (union overhead *) cp;
1783 /*
1784 * Round up to minimum allocation size boundary
1785 * and deduct from block count to reflect.
1786 */
1787
1788# if NEEDED_ALIGNMENT > MEM_ALIGNBYTES
1789 if (PTR2UV(ovp) & (NEEDED_ALIGNMENT - 1))
1790 fatalcroak("Misalignment of sbrk()\n");
1791 else
1792# endif
1793#ifndef I286 /* Again, this should always be ok on an 80286 */
1794 if (PTR2UV(ovp) & (MEM_ALIGNBYTES - 1)) {
1795 DEBUG_m(PerlIO_printf(Perl_debug_log,
1796 "fixing sbrk(): %d bytes off machine alignement\n",
1797 (int)(PTR2UV(ovp) & (MEM_ALIGNBYTES - 1))));
1798 ovp = INT2PTR(union overhead *,(PTR2UV(ovp) + MEM_ALIGNBYTES) &
1799 (MEM_ALIGNBYTES - 1));
1800 (*nblksp)--;
1801# if defined(DEBUGGING_MSTATS)
1802 /* This is only approx. if TWO_POT_OPTIMIZE: */
1803 sbrk_slack += (1 << (bucket >> BUCKET_POW2_SHIFT));
1804# endif
1805 }
1806#endif
1807 ; /* Finish "else" */
1808 sbrked_remains = require - needed;
1809 last_op = cp;
1810 }
1811#if !defined(PLAIN_MALLOC) && !defined(NO_FANCY_MALLOC)
1812 emergency_buffer_last_req = 0;
1813#endif
1814 last_sbrk_top = cp + require;
1815#ifdef DEBUGGING_MSTATS
1816 goodsbrk += require;
1817#endif
1818 return ovp;
1819}
1820
1821static int
1822getpages_adjacent(MEM_SIZE require)
1823{
1824 if (require <= sbrked_remains) {
1825 sbrked_remains -= require;
1826 } else {
1827 char *cp;
1828
1829 require -= sbrked_remains;
1830 /* We do not try to optimize sbrks here, we go for place. */
1831 cp = (char*) sbrk(require);
1832#ifdef DEBUGGING_MSTATS
1833 sbrks++;
1834 goodsbrk += require;
1835#endif
1836 if (cp == last_sbrk_top) {
1837 sbrked_remains = 0;
1838 last_sbrk_top = cp + require;
1839 } else {
1840 if (cp == (char*)-1) { /* Out of memory */
1841#ifdef DEBUGGING_MSTATS
1842 goodsbrk -= require;
1843#endif
1844 return 0;
1845 }
1846 /* Report the failure: */
1847 if (sbrked_remains)
1848 add_to_chain((void*)(last_sbrk_top - sbrked_remains),
1849 sbrked_remains, 0);
1850 add_to_chain((void*)cp, require, 0);
1851 sbrk_goodness -= SBRK_FAILURE_PRICE;
1852 sbrked_remains = 0;
1853 last_sbrk_top = 0;
1854 last_op = 0;
1855 return 0;
1856 }
1857 }
1858
1859 return 1;
1860}
1861
1862/*
1863 * Allocate more memory to the indicated bucket.
1864 */
1865static void
1866morecore(register int bucket)
1867{
1868 register union overhead *ovp;
1869 register int rnu; /* 2^rnu bytes will be requested */
1870 int nblks; /* become nblks blocks of the desired size */
1871 register MEM_SIZE siz, needed;
1872 static int were_called = 0;
1873
1874 if (nextf[bucket])
1875 return;
1876#ifndef NO_PERL_MALLOC_ENV
1877 if (!were_called) {
1878 /* It's the our first time. Initialize ourselves */
1879 were_called = 1; /* Avoid a loop */
1880 if (!MallocCfg[MallocCfg_skip_cfg_env]) {
1881 char *s = getenv("PERL_MALLOC_OPT"), *t = s, *off;
1882 const char *opts = PERL_MALLOC_OPT_CHARS;
1883 int changed = 0;
1884
1885 while ( t && t[0] && t[1] == '='
1886 && ((off = strchr(opts, *t))) ) {
1887 IV val = 0;
1888
1889 t += 2;
1890 while (*t <= '9' && *t >= '0')
1891 val = 10*val + *t++ - '0';
1892 if (!*t || *t == ';') {
1893 if (MallocCfg[off - opts] != val)
1894 changed = 1;
1895 MallocCfg[off - opts] = val;
1896 if (*t)
1897 t++;
1898 }
1899 }
1900 if (t && *t) {
1901 write2("Unrecognized part of PERL_MALLOC_OPT: \"");
1902 write2(t);
1903 write2("\"\n");
1904 }
1905 if (changed)
1906 MallocCfg[MallocCfg_cfg_env_read] = 1;
1907 }
1908 }
1909#endif
1910 if (bucket == sizeof(MEM_SIZE)*8*BUCKETS_PER_POW2) {
1911 MALLOC_UNLOCK;
1912 croak("%s", "Out of memory during ridiculously large request");
1913 }
1914 if (bucket > max_bucket)
1915 max_bucket = bucket;
1916
1917 rnu = ( (bucket <= (LOG_OF_MIN_ARENA << BUCKET_POW2_SHIFT))
1918 ? LOG_OF_MIN_ARENA
1919 : (bucket >> BUCKET_POW2_SHIFT) );
1920 /* This may be overwritten later: */
1921 nblks = 1 << (rnu - (bucket >> BUCKET_POW2_SHIFT)); /* how many blocks to get */
1922 needed = ((MEM_SIZE)1 << rnu) + POW2_OPTIMIZE_SURPLUS(bucket);
1923 if (nextf[rnu << BUCKET_POW2_SHIFT]) { /* 2048b bucket. */
1924 ovp = nextf[rnu << BUCKET_POW2_SHIFT] - 1 + CHUNK_SHIFT;
1925 nextf[rnu << BUCKET_POW2_SHIFT]
1926 = nextf[rnu << BUCKET_POW2_SHIFT]->ov_next;
1927#ifdef DEBUGGING_MSTATS
1928 nmalloc[rnu << BUCKET_POW2_SHIFT]--;
1929 start_slack -= M_OVERHEAD;
1930#endif
1931 DEBUG_m(PerlIO_printf(Perl_debug_log,
1932 "stealing %ld bytes from %ld arena\n",
1933 (long) needed, (long) rnu << BUCKET_POW2_SHIFT));
1934 } else if (chunk_chain
1935 && (ovp = (union overhead*) get_from_chain(needed))) {
1936 DEBUG_m(PerlIO_printf(Perl_debug_log,
1937 "stealing %ld bytes from chain\n",
1938 (long) needed));
1939 } else if ( (ovp = (union overhead*)
1940 get_from_bigger_buckets((rnu << BUCKET_POW2_SHIFT) + 1,
1941 needed)) ) {
1942 DEBUG_m(PerlIO_printf(Perl_debug_log,
1943 "stealing %ld bytes from bigger buckets\n",
1944 (long) needed));
1945 } else if (needed <= sbrked_remains) {
1946 ovp = (union overhead *)(last_sbrk_top - sbrked_remains);
1947 sbrked_remains -= needed;
1948 last_op = (char*)ovp;
1949 } else
1950 ovp = getpages(needed, &nblks, bucket);
1951
1952 if (!ovp)
1953 return;
1954 FILL_DEADBEEF((unsigned char*)ovp, needed);
1955
1956 /*
1957 * Add new memory allocated to that on
1958 * free list for this hash bucket.
1959 */
1960 siz = BUCKET_SIZE_NO_SURPLUS(bucket); /* No surplus if nblks > 1 */
1961#ifdef PACK_MALLOC
1962 *(u_char*)ovp = bucket; /* Fill index. */
1963 if (bucket <= MAX_PACKED) {
1964 ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket));
1965 nblks = N_BLKS(bucket);
1966# ifdef DEBUGGING_MSTATS
1967 start_slack += BLK_SHIFT(bucket);
1968# endif
1969 } else if (bucket < LOG_OF_MIN_ARENA * BUCKETS_PER_POW2) {
1970 ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket));
1971 siz -= sizeof(union overhead);
1972 } else ovp++; /* One chunk per block. */
1973#endif /* PACK_MALLOC */
1974 nextf[bucket] = ovp;
1975#ifdef DEBUGGING_MSTATS
1976 nmalloc[bucket] += nblks;
1977 if (bucket > MAX_PACKED) {
1978 start_slack += M_OVERHEAD * nblks;
1979 }
1980#endif
1981
1982 while (--nblks > 0) {
1983 ovp->ov_next = (union overhead *)((caddr_t)ovp + siz);
1984 ovp = (union overhead *)((caddr_t)ovp + siz);
1985 }
1986 /* Not all sbrks return zeroed memory.*/
1987 ovp->ov_next = (union overhead *)NULL;
1988#ifdef PACK_MALLOC
1989 if (bucket == 7*BUCKETS_PER_POW2) { /* Special case, explanation is above. */
1990 union overhead *n_op = nextf[7*BUCKETS_PER_POW2]->ov_next;
1991 nextf[7*BUCKETS_PER_POW2] =
1992 (union overhead *)((caddr_t)nextf[7*BUCKETS_PER_POW2]
1993 - sizeof(union overhead));
1994 nextf[7*BUCKETS_PER_POW2]->ov_next = n_op;
1995 }
1996#endif /* !PACK_MALLOC */
1997}
1998
1999Free_t
2000Perl_mfree(void *mp)
2001{
2002 register MEM_SIZE size;
2003 register union overhead *ovp;
2004 char *cp = (char*)mp;
2005#ifdef PACK_MALLOC
2006 u_char bucket;
2007#endif
2008
2009 DEBUG_m(PerlIO_printf(Perl_debug_log,
2010 "0x%"UVxf": (%05lu) free\n",
2011 PTR2UV(cp), (unsigned long)(PL_an++)));
2012
2013 if (cp == NULL)
2014 return;
2015#ifdef DEBUGGING
2016 if (PTR2UV(cp) & (MEM_ALIGNBYTES - 1))
2017 croak("%s", "wrong alignment in free()");
2018#endif
2019 ovp = (union overhead *)((caddr_t)cp
2020 - sizeof (union overhead) * CHUNK_SHIFT);
2021#ifdef PACK_MALLOC
2022 bucket = OV_INDEX(ovp);
2023#endif
2024#ifdef IGNORE_SMALL_BAD_FREE
2025 if ((bucket >= FIRST_BUCKET_WITH_CHECK)
2026 && (OV_MAGIC(ovp, bucket) != MAGIC))
2027#else
2028 if (OV_MAGIC(ovp, bucket) != MAGIC)
2029#endif
2030 {
2031 static int bad_free_warn = -1;
2032 if (bad_free_warn == -1) {
2033 dTHX;
2034 char *pbf = PerlEnv_getenv("PERL_BADFREE");
2035 bad_free_warn = (pbf) ? atoi(pbf) : 1;
2036 }
2037 if (!bad_free_warn)
2038 return;
2039#ifdef RCHECK
2040#ifdef PERL_CORE
2041 {
2042 dTHX;
2043 if (!PERL_IS_ALIVE || !PL_curcop || ckWARN_d(WARN_MALLOC))
2044 Perl_warner(aTHX_ packWARN(WARN_MALLOC), "%s free() ignored (RMAGIC, PERL_CORE)",
2045 ovp->ov_rmagic == RMAGIC - 1 ?
2046 "Duplicate" : "Bad");
2047 }
2048#else
2049 warn("%s free() ignored (RMAGIC)",
2050 ovp->ov_rmagic == RMAGIC - 1 ? "Duplicate" : "Bad");
2051#endif
2052#else
2053#ifdef PERL_CORE
2054 {
2055 dTHX;
2056 if (!PERL_IS_ALIVE || !PL_curcop || ckWARN_d(WARN_MALLOC))
2057 Perl_warner(aTHX_ packWARN(WARN_MALLOC), "%s", "Bad free() ignored (PERL_CORE)");
2058 }
2059#else
2060 warn("%s", "Bad free() ignored");
2061#endif
2062#endif
2063 return; /* sanity */
2064 }
2065#ifdef RCHECK
2066 ASSERT(ovp->ov_rmagic == RMAGIC, "chunk's head overwrite");
2067 if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) {
2068 int i;
2069 MEM_SIZE nbytes = ovp->ov_size + 1;
2070
2071 if ((i = nbytes & (RMAGIC_SZ-1))) {
2072 i = RMAGIC_SZ - i;
2073 while (i--) { /* nbytes - RMAGIC_SZ is end of alloced area */
2074 ASSERT(((caddr_t)ovp + nbytes - RMAGIC_SZ)[i] == RMAGIC_C,
2075 "chunk's tail overwrite");
2076 }
2077 }
2078 /* Same at RMAGIC_SZ-aligned RMAGIC */
2079 nbytes = (nbytes + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ-1);
2080 ASSERT(((u_int *)((caddr_t)ovp + nbytes))[-1] == RMAGIC,
2081 "chunk's tail overwrite");
2082 FILLCHECK_DEADBEEF((unsigned char*)((caddr_t)ovp + nbytes),
2083 BUCKET_SIZE(OV_INDEX(ovp)) - nbytes);
2084 }
2085 FILL_DEADBEEF((unsigned char*)(ovp+CHUNK_SHIFT),
2086 BUCKET_SIZE_REAL(OV_INDEX(ovp)) + RMAGIC_SZ);
2087 ovp->ov_rmagic = RMAGIC - 1;
2088#endif
2089 ASSERT(OV_INDEX(ovp) < NBUCKETS, "chunk's head overwrite");
2090 size = OV_INDEX(ovp);
2091
2092 MALLOC_LOCK;
2093 ovp->ov_next = nextf[size];
2094 nextf[size] = ovp;
2095 MALLOC_UNLOCK;
2096}
2097
2098/* There is no need to do any locking in realloc (with an exception of
2099 trying to grow in place if we are at the end of the chain).
2100 If somebody calls us from a different thread with the same address,
2101 we are sole anyway. */
2102
2103Malloc_t
2104Perl_realloc(void *mp, size_t nbytes)
2105{
2106 register MEM_SIZE onb;
2107 union overhead *ovp;
2108 char *res;
2109 int prev_bucket;
2110 register int bucket;
2111 int incr; /* 1 if does not fit, -1 if "easily" fits in a
2112 smaller bucket, otherwise 0. */
2113 char *cp = (char*)mp;
2114
2115#if defined(DEBUGGING) || !defined(PERL_CORE)
2116 MEM_SIZE size = nbytes;
2117
2118 if ((long)nbytes < 0)
2119 croak("%s", "panic: realloc");
2120#endif
2121
2122 BARK_64K_LIMIT("Reallocation",nbytes,size);
2123 if (!cp)
2124 return Perl_malloc(nbytes);
2125
2126 ovp = (union overhead *)((caddr_t)cp
2127 - sizeof (union overhead) * CHUNK_SHIFT);
2128 bucket = OV_INDEX(ovp);
2129
2130#ifdef IGNORE_SMALL_BAD_FREE
2131 if ((bucket >= FIRST_BUCKET_WITH_CHECK)
2132 && (OV_MAGIC(ovp, bucket) != MAGIC))
2133#else
2134 if (OV_MAGIC(ovp, bucket) != MAGIC)
2135#endif
2136 {
2137 static int bad_free_warn = -1;
2138 if (bad_free_warn == -1) {
2139 dTHX;
2140 char *pbf = PerlEnv_getenv("PERL_BADFREE");
2141 bad_free_warn = (pbf) ? atoi(pbf) : 1;
2142 }
2143 if (!bad_free_warn)
2144 return Nullch;
2145#ifdef RCHECK
2146#ifdef PERL_CORE
2147 {
2148 dTHX;
2149 if (!PERL_IS_ALIVE || !PL_curcop || ckWARN_d(WARN_MALLOC))
2150 Perl_warner(aTHX_ packWARN(WARN_MALLOC), "%srealloc() %signored",
2151 (ovp->ov_rmagic == RMAGIC - 1 ? "" : "Bad "),
2152 ovp->ov_rmagic == RMAGIC - 1
2153 ? "of freed memory " : "");
2154 }
2155#else
2156 warn2("%srealloc() %signored",
2157 (ovp->ov_rmagic == RMAGIC - 1 ? "" : "Bad "),
2158 ovp->ov_rmagic == RMAGIC - 1 ? "of freed memory " : "");
2159#endif
2160#else
2161#ifdef PERL_CORE
2162 {
2163 dTHX;
2164 if (!PERL_IS_ALIVE || !PL_curcop || ckWARN_d(WARN_MALLOC))
2165 Perl_warner(aTHX_ packWARN(WARN_MALLOC), "%s",
2166 "Bad realloc() ignored");
2167 }
2168#else
2169 warn("%s", "Bad realloc() ignored");
2170#endif
2171#endif
2172 return Nullch; /* sanity */
2173 }
2174
2175 onb = BUCKET_SIZE_REAL(bucket);
2176 /*
2177 * avoid the copy if same size block.
2178 * We are not agressive with boundary cases. Note that it might
2179 * (for a small number of cases) give false negative if
2180 * both new size and old one are in the bucket for
2181 * FIRST_BIG_POW2, but the new one is near the lower end.
2182 *
2183 * We do not try to go to 1.5 times smaller bucket so far.
2184 */
2185 if (nbytes > onb) incr = 1;
2186 else {
2187#ifdef DO_NOT_TRY_HARDER_WHEN_SHRINKING
2188 if ( /* This is a little bit pessimal if PACK_MALLOC: */
2189 nbytes > ( (onb >> 1) - M_OVERHEAD )
2190# ifdef TWO_POT_OPTIMIZE
2191 || (bucket == FIRST_BIG_POW2 && nbytes >= LAST_SMALL_BOUND )
2192# endif
2193 )
2194#else /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */
2195 prev_bucket = ( (bucket > MAX_PACKED + 1)
2196 ? bucket - BUCKETS_PER_POW2
2197 : bucket - 1);
2198 if (nbytes > BUCKET_SIZE_REAL(prev_bucket))
2199#endif /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */
2200 incr = 0;
2201 else incr = -1;
2202 }
2203#ifdef STRESS_REALLOC
2204 goto hard_way;
2205#endif
2206 if (incr == 0) {
2207 inplace_label:
2208#ifdef RCHECK
2209 /*
2210 * Record new allocated size of block and
2211 * bound space with magic numbers.
2212 */
2213 if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) {
2214 int i, nb = ovp->ov_size + 1;
2215
2216 if ((i = nb & (RMAGIC_SZ-1))) {
2217 i = RMAGIC_SZ - i;
2218 while (i--) { /* nb - RMAGIC_SZ is end of alloced area */
2219 ASSERT(((caddr_t)ovp + nb - RMAGIC_SZ)[i] == RMAGIC_C, "chunk's tail overwrite");
2220 }
2221 }
2222 /* Same at RMAGIC_SZ-aligned RMAGIC */
2223 nb = (nb + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ-1);
2224 ASSERT(((u_int *)((caddr_t)ovp + nb))[-1] == RMAGIC,
2225 "chunk's tail overwrite");
2226 FILLCHECK_DEADBEEF((unsigned char*)((caddr_t)ovp + nb),
2227 BUCKET_SIZE(OV_INDEX(ovp)) - nb);
2228 if (nbytes > ovp->ov_size + 1 - M_OVERHEAD)
2229 FILL_FEEDADAD((unsigned char*)cp + ovp->ov_size + 1 - M_OVERHEAD,
2230 nbytes - (ovp->ov_size + 1 - M_OVERHEAD));
2231 else
2232 FILL_DEADBEEF((unsigned char*)cp + nbytes,
2233 nb - M_OVERHEAD + RMAGIC_SZ - nbytes);
2234 /*
2235 * Convert amount of memory requested into
2236 * closest block size stored in hash buckets
2237 * which satisfies request. Account for
2238 * space used per block for accounting.
2239 */
2240 nbytes += M_OVERHEAD;
2241 ovp->ov_size = nbytes - 1;
2242 if ((i = nbytes & (RMAGIC_SZ-1))) {
2243 i = RMAGIC_SZ - i;
2244 while (i--) /* nbytes - RMAGIC_SZ is end of alloced area */
2245 ((caddr_t)ovp + nbytes - RMAGIC_SZ)[i]
2246 = RMAGIC_C;
2247 }
2248 /* Same at RMAGIC_SZ-aligned RMAGIC */
2249 nbytes = (nbytes + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ - 1);
2250 ((u_int *)((caddr_t)ovp + nbytes))[-1] = RMAGIC;
2251 }
2252#endif
2253 res = cp;
2254 DEBUG_m(PerlIO_printf(Perl_debug_log,
2255 "0x%"UVxf": (%05lu) realloc %ld bytes inplace\n",
2256 PTR2UV(res),(unsigned long)(PL_an++),
2257 (long)size));
2258 } else if (incr == 1 && (cp - M_OVERHEAD == last_op)
2259 && (onb > (1 << LOG_OF_MIN_ARENA))) {
2260 MEM_SIZE require, newarena = nbytes, pow;
2261 int shiftr;
2262
2263 POW2_OPTIMIZE_ADJUST(newarena);
2264 newarena = newarena + M_OVERHEAD;
2265 /* newarena = (newarena + 3) &~ 3; */
2266 shiftr = (newarena - 1) >> LOG_OF_MIN_ARENA;
2267 pow = LOG_OF_MIN_ARENA + 1;
2268 /* apart from this loop, this is O(1) */
2269 while (shiftr >>= 1)
2270 pow++;
2271 newarena = (1 << pow) + POW2_OPTIMIZE_SURPLUS(pow * BUCKETS_PER_POW2);
2272 require = newarena - onb - M_OVERHEAD;
2273
2274 MALLOC_LOCK;
2275 if (cp - M_OVERHEAD == last_op /* We *still* are the last chunk */
2276 && getpages_adjacent(require)) {
2277#ifdef DEBUGGING_MSTATS
2278 nmalloc[bucket]--;
2279 nmalloc[pow * BUCKETS_PER_POW2]++;
2280#endif
2281 *(cp - M_OVERHEAD) = pow * BUCKETS_PER_POW2; /* Fill index. */
2282 MALLOC_UNLOCK;
2283 goto inplace_label;
2284 } else {
2285 MALLOC_UNLOCK;
2286 goto hard_way;
2287 }
2288 } else {
2289 hard_way:
2290 DEBUG_m(PerlIO_printf(Perl_debug_log,
2291 "0x%"UVxf": (%05lu) realloc %ld bytes the hard way\n",
2292 PTR2UV(cp),(unsigned long)(PL_an++),
2293 (long)size));
2294 if ((res = (char*)Perl_malloc(nbytes)) == NULL)
2295 return (NULL);
2296 if (cp != res) /* common optimization */
2297 Copy(cp, res, (MEM_SIZE)(nbytes<onb?nbytes:onb), char);
2298 Perl_mfree(cp);
2299 }
2300 return ((Malloc_t)res);
2301}
2302
2303Malloc_t
2304Perl_calloc(register size_t elements, register size_t size)
2305{
2306 long sz = elements * size;
2307 Malloc_t p = Perl_malloc(sz);
2308
2309 if (p) {
2310 memset((void*)p, 0, sz);
2311 }
2312 return p;
2313}
2314
2315char *
2316Perl_strdup(const char *s)
2317{
2318 MEM_SIZE l = strlen(s);
2319 char *s1 = (char *)Perl_malloc(l+1);
2320
2321 return CopyD(s, s1, (MEM_SIZE)(l+1), char);
2322}
2323
2324#ifdef PERL_CORE
2325int
2326Perl_putenv(char *a)
2327{
2328 /* Sometimes system's putenv conflicts with my_setenv() - this is system
2329 malloc vs Perl's free(). */
2330 dTHX;
2331 char *var;
2332 char *val = a;
2333 MEM_SIZE l;
2334 char buf[80];
2335
2336 while (*val && *val != '=')
2337 val++;
2338 if (!*val)
2339 return -1;
2340 l = val - a;
2341 if (l < sizeof(buf))
2342 var = buf;
2343 else
2344 var = Perl_malloc(l + 1);
2345 Copy(a, var, l, char);
2346 var[l + 1] = 0;
2347 my_setenv(var, val+1);
2348 if (var != buf)
2349 Perl_mfree(var);
2350 return 0;
2351}
2352# endif
2353
2354MEM_SIZE
2355Perl_malloced_size(void *p)
2356{
2357 union overhead * const ovp = (union overhead *)
2358 ((caddr_t)p - sizeof (union overhead) * CHUNK_SHIFT);
2359 const int bucket = OV_INDEX(ovp);
2360#ifdef RCHECK
2361 /* The caller wants to have a complete control over the chunk,
2362 disable the memory checking inside the chunk. */
2363 if (bucket <= MAX_SHORT_BUCKET) {
2364 const MEM_SIZE size = BUCKET_SIZE_REAL(bucket);
2365 ovp->ov_size = size + M_OVERHEAD - 1;
2366 *((u_int *)((caddr_t)ovp + size + M_OVERHEAD - RMAGIC_SZ)) = RMAGIC;
2367 }
2368#endif
2369 return BUCKET_SIZE_REAL(bucket);
2370}
2371
2372# ifdef BUCKETS_ROOT2
2373# define MIN_EVEN_REPORT 6
2374# else
2375# define MIN_EVEN_REPORT MIN_BUCKET
2376# endif
2377
2378int
2379Perl_get_mstats(pTHX_ perl_mstats_t *buf, int buflen, int level)
2380{
2381#ifdef DEBUGGING_MSTATS
2382 register int i, j;
2383 register union overhead *p;
2384 struct chunk_chain_s* nextchain;
2385
2386 buf->topbucket = buf->topbucket_ev = buf->topbucket_odd
2387 = buf->totfree = buf->total = buf->total_chain = 0;
2388
2389 buf->minbucket = MIN_BUCKET;
2390 MALLOC_LOCK;
2391 for (i = MIN_BUCKET ; i < NBUCKETS; i++) {
2392 for (j = 0, p = nextf[i]; p; p = p->ov_next, j++)
2393 ;
2394 if (i < buflen) {
2395 buf->nfree[i] = j;
2396 buf->ntotal[i] = nmalloc[i];
2397 }
2398 buf->totfree += j * BUCKET_SIZE_REAL(i);
2399 buf->total += nmalloc[i] * BUCKET_SIZE_REAL(i);
2400 if (nmalloc[i]) {
2401 i % 2 ? (buf->topbucket_odd = i) : (buf->topbucket_ev = i);
2402 buf->topbucket = i;
2403 }
2404 }
2405 nextchain = chunk_chain;
2406 while (nextchain) {
2407 buf->total_chain += nextchain->size;
2408 nextchain = nextchain->next;
2409 }
2410 buf->total_sbrk = goodsbrk + sbrk_slack;
2411 buf->sbrks = sbrks;
2412 buf->sbrk_good = sbrk_goodness;
2413 buf->sbrk_slack = sbrk_slack;
2414 buf->start_slack = start_slack;
2415 buf->sbrked_remains = sbrked_remains;
2416 MALLOC_UNLOCK;
2417 buf->nbuckets = NBUCKETS;
2418 if (level) {
2419 for (i = MIN_BUCKET ; i < NBUCKETS; i++) {
2420 if (i >= buflen)
2421 break;
2422 buf->bucket_mem_size[i] = BUCKET_SIZE_NO_SURPLUS(i);
2423 buf->bucket_available_size[i] = BUCKET_SIZE_REAL(i);
2424 }
2425 }
2426#endif /* defined DEBUGGING_MSTATS */
2427 return 0; /* XXX unused */
2428}
2429/*
2430 * mstats - print out statistics about malloc
2431 *
2432 * Prints two lines of numbers, one showing the length of the free list
2433 * for each size category, the second showing the number of mallocs -
2434 * frees for each size category.
2435 */
2436void
2437Perl_dump_mstats(pTHX_ char *s)
2438{
2439#ifdef DEBUGGING_MSTATS
2440 register int i;
2441 perl_mstats_t buffer;
2442 UV nf[NBUCKETS];
2443 UV nt[NBUCKETS];
2444
2445 buffer.nfree = nf;
2446 buffer.ntotal = nt;
2447 get_mstats(&buffer, NBUCKETS, 0);
2448
2449 if (s)
2450 PerlIO_printf(Perl_error_log,
2451 "Memory allocation statistics %s (buckets %"IVdf"(%"IVdf")..%"IVdf"(%"IVdf")\n",
2452 s,
2453 (IV)BUCKET_SIZE_REAL(MIN_BUCKET),
2454 (IV)BUCKET_SIZE_NO_SURPLUS(MIN_BUCKET),
2455 (IV)BUCKET_SIZE_REAL(buffer.topbucket),
2456 (IV)BUCKET_SIZE_NO_SURPLUS(buffer.topbucket));
2457 PerlIO_printf(Perl_error_log, "%8"IVdf" free:", buffer.totfree);
2458 for (i = MIN_EVEN_REPORT; i <= buffer.topbucket; i += BUCKETS_PER_POW2) {
2459 PerlIO_printf(Perl_error_log,
2460 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2)
2461 ? " %5"UVuf
2462 : ((i < 12*BUCKETS_PER_POW2) ? " %3"UVuf : " %"UVuf)),
2463 buffer.nfree[i]);
2464 }
2465#ifdef BUCKETS_ROOT2
2466 PerlIO_printf(Perl_error_log, "\n\t ");
2467 for (i = MIN_BUCKET + 1; i <= buffer.topbucket_odd; i += BUCKETS_PER_POW2) {
2468 PerlIO_printf(Perl_error_log,
2469 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2)
2470 ? " %5"UVuf
2471 : ((i < 12*BUCKETS_PER_POW2) ? " %3"UVuf : " %"UVuf)),
2472 buffer.nfree[i]);
2473 }
2474#endif
2475 PerlIO_printf(Perl_error_log, "\n%8"IVdf" used:", buffer.total - buffer.totfree);
2476 for (i = MIN_EVEN_REPORT; i <= buffer.topbucket; i += BUCKETS_PER_POW2) {
2477 PerlIO_printf(Perl_error_log,
2478 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2)
2479 ? " %5"IVdf
2480 : ((i < 12*BUCKETS_PER_POW2) ? " %3"IVdf : " %"IVdf)),
2481 buffer.ntotal[i] - buffer.nfree[i]);
2482 }
2483#ifdef BUCKETS_ROOT2
2484 PerlIO_printf(Perl_error_log, "\n\t ");
2485 for (i = MIN_BUCKET + 1; i <= buffer.topbucket_odd; i += BUCKETS_PER_POW2) {
2486 PerlIO_printf(Perl_error_log,
2487 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2)
2488 ? " %5"IVdf
2489 : ((i < 12*BUCKETS_PER_POW2) ? " %3"IVdf : " %"IVdf)),
2490 buffer.ntotal[i] - buffer.nfree[i]);
2491 }
2492#endif
2493 PerlIO_printf(Perl_error_log, "\nTotal sbrk(): %"IVdf"/%"IVdf":%"IVdf". Odd ends: pad+heads+chain+tail: %"IVdf"+%"IVdf"+%"IVdf"+%"IVdf".\n",
2494 buffer.total_sbrk, buffer.sbrks, buffer.sbrk_good,
2495 buffer.sbrk_slack, buffer.start_slack,
2496 buffer.total_chain, buffer.sbrked_remains);
2497#endif /* DEBUGGING_MSTATS */
2498}
2499
2500#ifdef USE_PERL_SBRK
2501
2502# if defined(__MACHTEN_PPC__) || defined(NeXT) || defined(__NeXT__) || defined(PURIFY)
2503# define PERL_SBRK_VIA_MALLOC
2504# endif
2505
2506# ifdef PERL_SBRK_VIA_MALLOC
2507
2508/* it may seem schizophrenic to use perl's malloc and let it call system */
2509/* malloc, the reason for that is only the 3.2 version of the OS that had */
2510/* frequent core dumps within nxzonefreenolock. This sbrk routine put an */
2511/* end to the cores */
2512
2513# ifndef SYSTEM_ALLOC
2514# define SYSTEM_ALLOC(a) malloc(a)
2515# endif
2516# ifndef SYSTEM_ALLOC_ALIGNMENT
2517# define SYSTEM_ALLOC_ALIGNMENT MEM_ALIGNBYTES
2518# endif
2519
2520# endif /* PERL_SBRK_VIA_MALLOC */
2521
2522static IV Perl_sbrk_oldchunk;
2523static long Perl_sbrk_oldsize;
2524
2525# define PERLSBRK_32_K (1<<15)
2526# define PERLSBRK_64_K (1<<16)
2527
2528Malloc_t
2529Perl_sbrk(int size)
2530{
2531 IV got;
2532 int small, reqsize;
2533
2534 if (!size) return 0;
2535#ifdef PERL_CORE
2536 reqsize = size; /* just for the DEBUG_m statement */
2537#endif
2538#ifdef PACK_MALLOC
2539 size = (size + 0x7ff) & ~0x7ff;
2540#endif
2541 if (size <= Perl_sbrk_oldsize) {
2542 got = Perl_sbrk_oldchunk;
2543 Perl_sbrk_oldchunk += size;
2544 Perl_sbrk_oldsize -= size;
2545 } else {
2546 if (size >= PERLSBRK_32_K) {
2547 small = 0;
2548 } else {
2549 size = PERLSBRK_64_K;
2550 small = 1;
2551 }
2552# if NEEDED_ALIGNMENT > SYSTEM_ALLOC_ALIGNMENT
2553 size += NEEDED_ALIGNMENT - SYSTEM_ALLOC_ALIGNMENT;
2554# endif
2555 got = (IV)SYSTEM_ALLOC(size);
2556# if NEEDED_ALIGNMENT > SYSTEM_ALLOC_ALIGNMENT
2557 got = (got + NEEDED_ALIGNMENT - 1) & ~(NEEDED_ALIGNMENT - 1);
2558# endif
2559 if (small) {
2560 /* Chunk is small, register the rest for future allocs. */
2561 Perl_sbrk_oldchunk = got + reqsize;
2562 Perl_sbrk_oldsize = size - reqsize;
2563 }
2564 }
2565
2566 DEBUG_m(PerlIO_printf(Perl_debug_log, "sbrk malloc size %ld (reqsize %ld), left size %ld, give addr 0x%"UVxf"\n",
2567 size, reqsize, Perl_sbrk_oldsize, PTR2UV(got)));
2568
2569 return (void *)got;
2570}
2571
2572#endif /* ! defined USE_PERL_SBRK */
2573
2574/*
2575 * Local variables:
2576 * c-indentation-style: bsd
2577 * c-basic-offset: 4
2578 * indent-tabs-mode: t
2579 * End:
2580 *
2581 * ex: set ts=8 sts=4 sw=4 noet:
2582 */
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