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1 | #ifdef MALLOC_PROVIDED |
2 | int _dummy_mallocr = 1; | |
3 | #else | |
4 | /* ---------- To make a malloc.h, start cutting here ------------ */ | |
5 | ||
6 | /* | |
7 | A version of malloc/free/realloc written by Doug Lea and released to the | |
8 | public domain. Send questions/comments/complaints/performance data | |
9 | to dl@cs.oswego.edu | |
10 | ||
11 | * VERSION 2.6.4 Thu Nov 28 07:54:55 1996 Doug Lea (dl at gee) | |
12 | ||
13 | Note: There may be an updated version of this malloc obtainable at | |
14 | ftp://g.oswego.edu/pub/misc/malloc.c | |
15 | Check before installing! | |
16 | ||
17 | * Why use this malloc? | |
18 | ||
19 | This is not the fastest, most space-conserving, most portable, or | |
20 | most tunable malloc ever written. However it is among the fastest | |
21 | while also being among the most space-conserving, portable and tunable. | |
22 | Consistent balance across these factors results in a good general-purpose | |
23 | allocator. For a high-level description, see | |
24 | http://g.oswego.edu/dl/html/malloc.html | |
25 | ||
26 | * Synopsis of public routines | |
27 | ||
28 | (Much fuller descriptions are contained in the program documentation below.) | |
29 | ||
30 | malloc(size_t n); | |
31 | Return a pointer to a newly allocated chunk of at least n bytes, or null | |
32 | if no space is available. | |
33 | free(Void_t* p); | |
34 | Release the chunk of memory pointed to by p, or no effect if p is null. | |
35 | realloc(Void_t* p, size_t n); | |
36 | Return a pointer to a chunk of size n that contains the same data | |
37 | as does chunk p up to the minimum of (n, p's size) bytes, or null | |
38 | if no space is available. The returned pointer may or may not be | |
39 | the same as p. If p is null, equivalent to malloc. Unless the | |
40 | #define REALLOC_ZERO_BYTES_FREES below is set, realloc with a | |
41 | size argument of zero (re)allocates a minimum-sized chunk. | |
42 | memalign(size_t alignment, size_t n); | |
43 | Return a pointer to a newly allocated chunk of n bytes, aligned | |
44 | in accord with the alignment argument, which must be a power of | |
45 | two. | |
46 | valloc(size_t n); | |
47 | Equivalent to memalign(pagesize, n), where pagesize is the page | |
48 | size of the system (or as near to this as can be figured out from | |
49 | all the includes/defines below.) | |
50 | pvalloc(size_t n); | |
51 | Equivalent to valloc(minimum-page-that-holds(n)), that is, | |
52 | round up n to nearest pagesize. | |
53 | calloc(size_t unit, size_t quantity); | |
54 | Returns a pointer to quantity * unit bytes, with all locations | |
55 | set to zero. | |
56 | cfree(Void_t* p); | |
57 | Equivalent to free(p). | |
58 | malloc_trim(size_t pad); | |
59 | Release all but pad bytes of freed top-most memory back | |
60 | to the system. Return 1 if successful, else 0. | |
61 | malloc_usable_size(Void_t* p); | |
62 | Report the number usable allocated bytes associated with allocated | |
63 | chunk p. This may or may not report more bytes than were requested, | |
64 | due to alignment and minimum size constraints. | |
65 | malloc_stats(); | |
66 | Prints brief summary statistics on stderr. | |
67 | mallinfo() | |
68 | Returns (by copy) a struct containing various summary statistics. | |
69 | mallopt(int parameter_number, int parameter_value) | |
70 | Changes one of the tunable parameters described below. Returns | |
71 | 1 if successful in changing the parameter, else 0. | |
72 | ||
73 | * Vital statistics: | |
74 | ||
75 | Alignment: 8-byte | |
76 | 8 byte alignment is currently hardwired into the design. This | |
77 | seems to suffice for all current machines and C compilers. | |
78 | ||
79 | Assumed pointer representation: 4 or 8 bytes | |
80 | Code for 8-byte pointers is untested by me but has worked | |
81 | reliably by Wolfram Gloger, who contributed most of the | |
82 | changes supporting this. | |
83 | ||
84 | Assumed size_t representation: 4 or 8 bytes | |
85 | Note that size_t is allowed to be 4 bytes even if pointers are 8. | |
86 | ||
87 | Minimum overhead per allocated chunk: 4 or 8 bytes | |
88 | Each malloced chunk has a hidden overhead of 4 bytes holding size | |
89 | and status information. | |
90 | ||
91 | Minimum allocated size: 4-byte ptrs: 16 bytes (including 4 overhead) | |
92 | 8-byte ptrs: 24/32 bytes (including, 4/8 overhead) | |
93 | ||
94 | When a chunk is freed, 12 (for 4byte ptrs) or 20 (for 8 byte | |
95 | ptrs but 4 byte size) or 24 (for 8/8) additional bytes are | |
96 | needed; 4 (8) for a trailing size field | |
97 | and 8 (16) bytes for free list pointers. Thus, the minimum | |
98 | allocatable size is 16/24/32 bytes. | |
99 | ||
100 | Even a request for zero bytes (i.e., malloc(0)) returns a | |
101 | pointer to something of the minimum allocatable size. | |
102 | ||
103 | Maximum allocated size: 4-byte size_t: 2^31 - 8 bytes | |
104 | 8-byte size_t: 2^63 - 16 bytes | |
105 | ||
106 | It is assumed that (possibly signed) size_t bit values suffice to | |
107 | represent chunk sizes. `Possibly signed' is due to the fact | |
108 | that `size_t' may be defined on a system as either a signed or | |
109 | an unsigned type. To be conservative, values that would appear | |
110 | as negative numbers are avoided. | |
111 | Requests for sizes with a negative sign bit will return a | |
112 | minimum-sized chunk. | |
113 | ||
114 | Maximum overhead wastage per allocated chunk: normally 15 bytes | |
115 | ||
116 | Alignnment demands, plus the minimum allocatable size restriction | |
117 | make the normal worst-case wastage 15 bytes (i.e., up to 15 | |
118 | more bytes will be allocated than were requested in malloc), with | |
119 | two exceptions: | |
120 | 1. Because requests for zero bytes allocate non-zero space, | |
121 | the worst case wastage for a request of zero bytes is 24 bytes. | |
122 | 2. For requests >= mmap_threshold that are serviced via | |
123 | mmap(), the worst case wastage is 8 bytes plus the remainder | |
124 | from a system page (the minimal mmap unit); typically 4096 bytes. | |
125 | ||
126 | * Limitations | |
127 | ||
128 | Here are some features that are NOT currently supported | |
129 | ||
130 | * No user-definable hooks for callbacks and the like. | |
131 | * No automated mechanism for fully checking that all accesses | |
132 | to malloced memory stay within their bounds. | |
133 | * No support for compaction. | |
134 | ||
135 | * Synopsis of compile-time options: | |
136 | ||
137 | People have reported using previous versions of this malloc on all | |
138 | versions of Unix, sometimes by tweaking some of the defines | |
139 | below. It has been tested most extensively on Solaris and | |
140 | Linux. It is also reported to work on WIN32 platforms. | |
141 | People have also reported adapting this malloc for use in | |
142 | stand-alone embedded systems. | |
143 | ||
144 | The implementation is in straight, hand-tuned ANSI C. Among other | |
145 | consequences, it uses a lot of macros. Because of this, to be at | |
146 | all usable, this code should be compiled using an optimizing compiler | |
147 | (for example gcc -O2) that can simplify expressions and control | |
148 | paths. | |
149 | ||
150 | __STD_C (default: derived from C compiler defines) | |
151 | Nonzero if using ANSI-standard C compiler, a C++ compiler, or | |
152 | a C compiler sufficiently close to ANSI to get away with it. | |
153 | DEBUG (default: NOT defined) | |
154 | Define to enable debugging. Adds fairly extensive assertion-based | |
155 | checking to help track down memory errors, but noticeably slows down | |
156 | execution. | |
157 | SEPARATE_OBJECTS (default: NOT defined) | |
158 | Define this to compile into separate .o files. You must then | |
159 | compile malloc.c several times, defining a DEFINE_* macro each | |
160 | time. The list of DEFINE_* macros appears below. | |
161 | MALLOC_LOCK (default: NOT defined) | |
162 | MALLOC_UNLOCK (default: NOT defined) | |
163 | Define these to C expressions which are run to lock and unlock | |
164 | the malloc data structures. Calls may be nested; that is, | |
165 | MALLOC_LOCK may be called more than once before the corresponding | |
166 | MALLOC_UNLOCK calls. MALLOC_LOCK must avoid waiting for a lock | |
167 | that it already holds. | |
168 | MALLOC_ALIGNMENT (default: NOT defined) | |
169 | Define this to 16 if you need 16 byte alignment instead of 8 byte alignment | |
170 | which is the normal default. | |
8a0efa53 CF |
171 | REALLOC_ZERO_BYTES_FREES (default: NOT defined) |
172 | Define this if you think that realloc(p, 0) should be equivalent | |
173 | to free(p). Otherwise, since malloc returns a unique pointer for | |
174 | malloc(0), so does realloc(p, 0). | |
175 | HAVE_MEMCPY (default: defined) | |
176 | Define if you are not otherwise using ANSI STD C, but still | |
177 | have memcpy and memset in your C library and want to use them. | |
178 | Otherwise, simple internal versions are supplied. | |
179 | USE_MEMCPY (default: 1 if HAVE_MEMCPY is defined, 0 otherwise) | |
180 | Define as 1 if you want the C library versions of memset and | |
181 | memcpy called in realloc and calloc (otherwise macro versions are used). | |
182 | At least on some platforms, the simple macro versions usually | |
183 | outperform libc versions. | |
184 | HAVE_MMAP (default: defined as 1) | |
185 | Define to non-zero to optionally make malloc() use mmap() to | |
186 | allocate very large blocks. | |
187 | HAVE_MREMAP (default: defined as 0 unless Linux libc set) | |
188 | Define to non-zero to optionally make realloc() use mremap() to | |
189 | reallocate very large blocks. | |
190 | malloc_getpagesize (default: derived from system #includes) | |
191 | Either a constant or routine call returning the system page size. | |
192 | HAVE_USR_INCLUDE_MALLOC_H (default: NOT defined) | |
193 | Optionally define if you are on a system with a /usr/include/malloc.h | |
194 | that declares struct mallinfo. It is not at all necessary to | |
195 | define this even if you do, but will ensure consistency. | |
196 | INTERNAL_SIZE_T (default: size_t) | |
197 | Define to a 32-bit type (probably `unsigned int') if you are on a | |
198 | 64-bit machine, yet do not want or need to allow malloc requests of | |
199 | greater than 2^31 to be handled. This saves space, especially for | |
200 | very small chunks. | |
201 | INTERNAL_LINUX_C_LIB (default: NOT defined) | |
202 | Defined only when compiled as part of Linux libc. | |
203 | Also note that there is some odd internal name-mangling via defines | |
204 | (for example, internally, `malloc' is named `mALLOc') needed | |
205 | when compiling in this case. These look funny but don't otherwise | |
206 | affect anything. | |
207 | INTERNAL_NEWLIB (default: NOT defined) | |
208 | Defined only when compiled as part of the Cygnus newlib | |
209 | distribution. | |
210 | WIN32 (default: undefined) | |
211 | Define this on MS win (95, nt) platforms to compile in sbrk emulation. | |
212 | LACKS_UNISTD_H (default: undefined) | |
213 | Define this if your system does not have a <unistd.h>. | |
214 | MORECORE (default: sbrk) | |
215 | The name of the routine to call to obtain more memory from the system. | |
216 | MORECORE_FAILURE (default: -1) | |
217 | The value returned upon failure of MORECORE. | |
218 | MORECORE_CLEARS (default 1) | |
219 | True (1) if the routine mapped to MORECORE zeroes out memory (which | |
220 | holds for sbrk). | |
221 | DEFAULT_TRIM_THRESHOLD | |
222 | DEFAULT_TOP_PAD | |
223 | DEFAULT_MMAP_THRESHOLD | |
224 | DEFAULT_MMAP_MAX | |
225 | Default values of tunable parameters (described in detail below) | |
226 | controlling interaction with host system routines (sbrk, mmap, etc). | |
227 | These values may also be changed dynamically via mallopt(). The | |
228 | preset defaults are those that give best performance for typical | |
229 | programs/systems. | |
230 | ||
231 | ||
232 | */ | |
233 | ||
234 | \f | |
235 | ||
236 | ||
237 | /* Preliminaries */ | |
238 | ||
239 | #ifndef __STD_C | |
240 | #ifdef __STDC__ | |
241 | #define __STD_C 1 | |
242 | #else | |
243 | #if __cplusplus | |
244 | #define __STD_C 1 | |
245 | #else | |
246 | #define __STD_C 0 | |
247 | #endif /*__cplusplus*/ | |
248 | #endif /*__STDC__*/ | |
249 | #endif /*__STD_C*/ | |
250 | ||
251 | #ifndef Void_t | |
252 | #if __STD_C | |
253 | #define Void_t void | |
254 | #else | |
255 | #define Void_t char | |
256 | #endif | |
257 | #endif /*Void_t*/ | |
258 | ||
259 | #if __STD_C | |
260 | #include <stddef.h> /* for size_t */ | |
261 | #else | |
262 | #include <sys/types.h> | |
263 | #endif | |
264 | ||
265 | #ifdef __cplusplus | |
266 | extern "C" { | |
267 | #endif | |
268 | ||
269 | #include <stdio.h> /* needed for malloc_stats */ | |
659e7062 | 270 | #include <limits.h> /* needed for overflow checks */ |
8a0efa53 | 271 | |
fe47ea33 JJ |
272 | #ifdef WIN32 |
273 | #define WIN32_LEAN_AND_MEAN | |
274 | #include <windows.h> | |
275 | #endif | |
8a0efa53 CF |
276 | |
277 | /* | |
278 | Compile-time options | |
279 | */ | |
280 | ||
281 | ||
282 | /* | |
283 | ||
284 | Special defines for Cygnus newlib distribution. | |
285 | ||
286 | */ | |
287 | ||
288 | #ifdef INTERNAL_NEWLIB | |
289 | ||
290 | #include <sys/config.h> | |
291 | ||
292 | /* | |
293 | In newlib, all the publically visible routines take a reentrancy | |
294 | pointer. We don't currently do anything much with it, but we do | |
295 | pass it to the lock routine. | |
296 | */ | |
297 | ||
298 | #include <reent.h> | |
299 | ||
300 | #define POINTER_UINT unsigned _POINTER_INT | |
301 | #define SEPARATE_OBJECTS | |
302 | #define HAVE_MMAP 0 | |
303 | #define MORECORE(size) _sbrk_r(reent_ptr, (size)) | |
304 | #define MORECORE_CLEARS 0 | |
305 | #define MALLOC_LOCK __malloc_lock(reent_ptr) | |
306 | #define MALLOC_UNLOCK __malloc_unlock(reent_ptr) | |
307 | ||
82ea92f3 CF |
308 | #ifdef __CYGWIN__ |
309 | # undef _WIN32 | |
310 | # undef WIN32 | |
311 | #endif | |
312 | ||
8a0efa53 CF |
313 | #ifndef _WIN32 |
314 | #ifdef SMALL_MEMORY | |
315 | #define malloc_getpagesize (128) | |
316 | #else | |
317 | #define malloc_getpagesize (4096) | |
318 | #endif | |
319 | #endif | |
320 | ||
321 | #if __STD_C | |
322 | extern void __malloc_lock(struct _reent *); | |
323 | extern void __malloc_unlock(struct _reent *); | |
324 | #else | |
325 | extern void __malloc_lock(); | |
326 | extern void __malloc_unlock(); | |
327 | #endif | |
328 | ||
329 | #if __STD_C | |
330 | #define RARG struct _reent *reent_ptr, | |
331 | #define RONEARG struct _reent *reent_ptr | |
332 | #else | |
333 | #define RARG reent_ptr | |
334 | #define RONEARG reent_ptr | |
335 | #define RDECL struct _reent *reent_ptr; | |
336 | #endif | |
337 | ||
338 | #define RCALL reent_ptr, | |
339 | #define RONECALL reent_ptr | |
340 | ||
341 | #else /* ! INTERNAL_NEWLIB */ | |
342 | ||
343 | #define POINTER_UINT unsigned long | |
344 | #define RARG | |
345 | #define RONEARG | |
346 | #define RDECL | |
347 | #define RCALL | |
348 | #define RONECALL | |
349 | ||
350 | #endif /* ! INTERNAL_NEWLIB */ | |
351 | ||
352 | /* | |
353 | Debugging: | |
354 | ||
355 | Because freed chunks may be overwritten with link fields, this | |
356 | malloc will often die when freed memory is overwritten by user | |
357 | programs. This can be very effective (albeit in an annoying way) | |
358 | in helping track down dangling pointers. | |
359 | ||
360 | If you compile with -DDEBUG, a number of assertion checks are | |
361 | enabled that will catch more memory errors. You probably won't be | |
362 | able to make much sense of the actual assertion errors, but they | |
363 | should help you locate incorrectly overwritten memory. The | |
364 | checking is fairly extensive, and will slow down execution | |
365 | noticeably. Calling malloc_stats or mallinfo with DEBUG set will | |
366 | attempt to check every non-mmapped allocated and free chunk in the | |
367 | course of computing the summmaries. (By nature, mmapped regions | |
368 | cannot be checked very much automatically.) | |
369 | ||
370 | Setting DEBUG may also be helpful if you are trying to modify | |
371 | this code. The assertions in the check routines spell out in more | |
372 | detail the assumptions and invariants underlying the algorithms. | |
373 | ||
374 | */ | |
375 | ||
376 | #if DEBUG | |
377 | #include <assert.h> | |
378 | #else | |
379 | #define assert(x) ((void)0) | |
380 | #endif | |
381 | ||
382 | ||
383 | /* | |
384 | SEPARATE_OBJECTS should be defined if you want each function to go | |
385 | into a separate .o file. You must then compile malloc.c once per | |
386 | function, defining the appropriate DEFINE_ macro. See below for the | |
387 | list of macros. | |
388 | */ | |
389 | ||
390 | #ifndef SEPARATE_OBJECTS | |
391 | #define DEFINE_MALLOC | |
392 | #define DEFINE_FREE | |
393 | #define DEFINE_REALLOC | |
394 | #define DEFINE_CALLOC | |
395 | #define DEFINE_CFREE | |
396 | #define DEFINE_MEMALIGN | |
397 | #define DEFINE_VALLOC | |
398 | #define DEFINE_PVALLOC | |
399 | #define DEFINE_MALLINFO | |
400 | #define DEFINE_MALLOC_STATS | |
401 | #define DEFINE_MALLOC_USABLE_SIZE | |
402 | #define DEFINE_MALLOPT | |
403 | ||
404 | #define STATIC static | |
405 | #else | |
406 | #define STATIC | |
407 | #endif | |
408 | ||
409 | /* | |
410 | Define MALLOC_LOCK and MALLOC_UNLOCK to C expressions to run to | |
411 | lock and unlock the malloc data structures. MALLOC_LOCK may be | |
412 | called recursively. | |
413 | */ | |
414 | ||
415 | #ifndef MALLOC_LOCK | |
416 | #define MALLOC_LOCK | |
417 | #endif | |
418 | ||
419 | #ifndef MALLOC_UNLOCK | |
420 | #define MALLOC_UNLOCK | |
421 | #endif | |
422 | ||
423 | /* | |
424 | INTERNAL_SIZE_T is the word-size used for internal bookkeeping | |
425 | of chunk sizes. On a 64-bit machine, you can reduce malloc | |
426 | overhead by defining INTERNAL_SIZE_T to be a 32 bit `unsigned int' | |
427 | at the expense of not being able to handle requests greater than | |
428 | 2^31. This limitation is hardly ever a concern; you are encouraged | |
429 | to set this. However, the default version is the same as size_t. | |
430 | */ | |
431 | ||
432 | #ifndef INTERNAL_SIZE_T | |
433 | #define INTERNAL_SIZE_T size_t | |
434 | #endif | |
435 | ||
436 | /* | |
437 | Following is needed on implementations whereby long > size_t. | |
438 | The problem is caused because the code performs subtractions of | |
439 | size_t values and stores the result in long values. In the case | |
440 | where long > size_t and the first value is actually less than | |
441 | the second value, the resultant value is positive. For example, | |
442 | (long)(x - y) where x = 0 and y is 1 ends up being 0x00000000FFFFFFFF | |
443 | which is 2*31 - 1 instead of 0xFFFFFFFFFFFFFFFF. This is due to the | |
444 | fact that assignment from unsigned to signed won't sign extend. | |
445 | */ | |
446 | ||
f770cf44 RS |
447 | #define long_sub_size_t(x, y) \ |
448 | (sizeof (long) > sizeof (INTERNAL_SIZE_T) && x < y \ | |
449 | ? -(long) (y - x) \ | |
450 | : (long) (x - y)) | |
8a0efa53 CF |
451 | |
452 | /* | |
453 | REALLOC_ZERO_BYTES_FREES should be set if a call to | |
454 | realloc with zero bytes should be the same as a call to free. | |
455 | Some people think it should. Otherwise, since this malloc | |
456 | returns a unique pointer for malloc(0), so does realloc(p, 0). | |
457 | */ | |
458 | ||
459 | ||
460 | /* #define REALLOC_ZERO_BYTES_FREES */ | |
461 | ||
462 | ||
463 | /* | |
464 | WIN32 causes an emulation of sbrk to be compiled in | |
465 | mmap-based options are not currently supported in WIN32. | |
466 | */ | |
467 | ||
468 | /* #define WIN32 */ | |
469 | #ifdef WIN32 | |
470 | #define MORECORE wsbrk | |
471 | #define HAVE_MMAP 0 | |
472 | #endif | |
473 | ||
474 | ||
475 | /* | |
476 | HAVE_MEMCPY should be defined if you are not otherwise using | |
477 | ANSI STD C, but still have memcpy and memset in your C library | |
478 | and want to use them in calloc and realloc. Otherwise simple | |
479 | macro versions are defined here. | |
480 | ||
481 | USE_MEMCPY should be defined as 1 if you actually want to | |
482 | have memset and memcpy called. People report that the macro | |
483 | versions are often enough faster than libc versions on many | |
484 | systems that it is better to use them. | |
485 | ||
486 | */ | |
487 | ||
488 | #define HAVE_MEMCPY | |
489 | ||
490 | #ifndef USE_MEMCPY | |
491 | #ifdef HAVE_MEMCPY | |
492 | #define USE_MEMCPY 1 | |
493 | #else | |
494 | #define USE_MEMCPY 0 | |
495 | #endif | |
496 | #endif | |
497 | ||
498 | #if (__STD_C || defined(HAVE_MEMCPY)) | |
499 | ||
500 | #if __STD_C | |
501 | void* memset(void*, int, size_t); | |
502 | void* memcpy(void*, const void*, size_t); | |
503 | #else | |
504 | Void_t* memset(); | |
505 | Void_t* memcpy(); | |
506 | #endif | |
507 | #endif | |
508 | ||
509 | #if USE_MEMCPY | |
510 | ||
511 | /* The following macros are only invoked with (2n+1)-multiples of | |
512 | INTERNAL_SIZE_T units, with a positive integer n. This is exploited | |
513 | for fast inline execution when n is small. */ | |
514 | ||
515 | #define MALLOC_ZERO(charp, nbytes) \ | |
516 | do { \ | |
517 | INTERNAL_SIZE_T mzsz = (nbytes); \ | |
518 | if(mzsz <= 9*sizeof(mzsz)) { \ | |
519 | INTERNAL_SIZE_T* mz = (INTERNAL_SIZE_T*) (charp); \ | |
520 | if(mzsz >= 5*sizeof(mzsz)) { *mz++ = 0; \ | |
521 | *mz++ = 0; \ | |
522 | if(mzsz >= 7*sizeof(mzsz)) { *mz++ = 0; \ | |
523 | *mz++ = 0; \ | |
524 | if(mzsz >= 9*sizeof(mzsz)) { *mz++ = 0; \ | |
525 | *mz++ = 0; }}} \ | |
526 | *mz++ = 0; \ | |
527 | *mz++ = 0; \ | |
528 | *mz = 0; \ | |
529 | } else memset((charp), 0, mzsz); \ | |
530 | } while(0) | |
531 | ||
532 | #define MALLOC_COPY(dest,src,nbytes) \ | |
533 | do { \ | |
534 | INTERNAL_SIZE_T mcsz = (nbytes); \ | |
535 | if(mcsz <= 9*sizeof(mcsz)) { \ | |
536 | INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) (src); \ | |
537 | INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) (dest); \ | |
538 | if(mcsz >= 5*sizeof(mcsz)) { *mcdst++ = *mcsrc++; \ | |
539 | *mcdst++ = *mcsrc++; \ | |
540 | if(mcsz >= 7*sizeof(mcsz)) { *mcdst++ = *mcsrc++; \ | |
541 | *mcdst++ = *mcsrc++; \ | |
542 | if(mcsz >= 9*sizeof(mcsz)) { *mcdst++ = *mcsrc++; \ | |
543 | *mcdst++ = *mcsrc++; }}} \ | |
544 | *mcdst++ = *mcsrc++; \ | |
545 | *mcdst++ = *mcsrc++; \ | |
546 | *mcdst = *mcsrc ; \ | |
547 | } else memcpy(dest, src, mcsz); \ | |
548 | } while(0) | |
549 | ||
550 | #else /* !USE_MEMCPY */ | |
551 | ||
552 | /* Use Duff's device for good zeroing/copying performance. */ | |
553 | ||
554 | #define MALLOC_ZERO(charp, nbytes) \ | |
555 | do { \ | |
556 | INTERNAL_SIZE_T* mzp = (INTERNAL_SIZE_T*)(charp); \ | |
557 | long mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T), mcn; \ | |
558 | if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \ | |
559 | switch (mctmp) { \ | |
560 | case 0: for(;;) { *mzp++ = 0; \ | |
561 | case 7: *mzp++ = 0; \ | |
562 | case 6: *mzp++ = 0; \ | |
563 | case 5: *mzp++ = 0; \ | |
564 | case 4: *mzp++ = 0; \ | |
565 | case 3: *mzp++ = 0; \ | |
566 | case 2: *mzp++ = 0; \ | |
567 | case 1: *mzp++ = 0; if(mcn <= 0) break; mcn--; } \ | |
568 | } \ | |
569 | } while(0) | |
570 | ||
571 | #define MALLOC_COPY(dest,src,nbytes) \ | |
572 | do { \ | |
573 | INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) src; \ | |
574 | INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) dest; \ | |
575 | long mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T), mcn; \ | |
576 | if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \ | |
577 | switch (mctmp) { \ | |
578 | case 0: for(;;) { *mcdst++ = *mcsrc++; \ | |
579 | case 7: *mcdst++ = *mcsrc++; \ | |
580 | case 6: *mcdst++ = *mcsrc++; \ | |
581 | case 5: *mcdst++ = *mcsrc++; \ | |
582 | case 4: *mcdst++ = *mcsrc++; \ | |
583 | case 3: *mcdst++ = *mcsrc++; \ | |
584 | case 2: *mcdst++ = *mcsrc++; \ | |
585 | case 1: *mcdst++ = *mcsrc++; if(mcn <= 0) break; mcn--; } \ | |
586 | } \ | |
587 | } while(0) | |
588 | ||
589 | #endif | |
590 | ||
591 | ||
592 | /* | |
593 | Define HAVE_MMAP to optionally make malloc() use mmap() to | |
594 | allocate very large blocks. These will be returned to the | |
595 | operating system immediately after a free(). | |
596 | */ | |
597 | ||
598 | #ifndef HAVE_MMAP | |
599 | #define HAVE_MMAP 1 | |
600 | #endif | |
601 | ||
602 | /* | |
603 | Define HAVE_MREMAP to make realloc() use mremap() to re-allocate | |
604 | large blocks. This is currently only possible on Linux with | |
605 | kernel versions newer than 1.3.77. | |
606 | */ | |
607 | ||
608 | #ifndef HAVE_MREMAP | |
609 | #ifdef INTERNAL_LINUX_C_LIB | |
610 | #define HAVE_MREMAP 1 | |
611 | #else | |
612 | #define HAVE_MREMAP 0 | |
613 | #endif | |
614 | #endif | |
615 | ||
616 | #if HAVE_MMAP | |
617 | ||
618 | #include <unistd.h> | |
619 | #include <fcntl.h> | |
620 | #include <sys/mman.h> | |
621 | ||
622 | #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON) | |
623 | #define MAP_ANONYMOUS MAP_ANON | |
624 | #endif | |
625 | ||
626 | #endif /* HAVE_MMAP */ | |
627 | ||
628 | /* | |
629 | Access to system page size. To the extent possible, this malloc | |
630 | manages memory from the system in page-size units. | |
631 | ||
632 | The following mechanics for getpagesize were adapted from | |
633 | bsd/gnu getpagesize.h | |
634 | */ | |
635 | ||
636 | #ifndef LACKS_UNISTD_H | |
637 | # include <unistd.h> | |
638 | #endif | |
639 | ||
640 | #ifndef malloc_getpagesize | |
641 | # ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */ | |
642 | # ifndef _SC_PAGE_SIZE | |
643 | # define _SC_PAGE_SIZE _SC_PAGESIZE | |
644 | # endif | |
645 | # endif | |
646 | # ifdef _SC_PAGE_SIZE | |
647 | # define malloc_getpagesize sysconf(_SC_PAGE_SIZE) | |
648 | # else | |
649 | # if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE) | |
650 | extern size_t getpagesize(); | |
651 | # define malloc_getpagesize getpagesize() | |
652 | # else | |
653 | # include <sys/param.h> | |
654 | # ifdef EXEC_PAGESIZE | |
655 | # define malloc_getpagesize EXEC_PAGESIZE | |
656 | # else | |
657 | # ifdef NBPG | |
658 | # ifndef CLSIZE | |
659 | # define malloc_getpagesize NBPG | |
660 | # else | |
661 | # define malloc_getpagesize (NBPG * CLSIZE) | |
662 | # endif | |
663 | # else | |
664 | # ifdef NBPC | |
665 | # define malloc_getpagesize NBPC | |
666 | # else | |
667 | # ifdef PAGESIZE | |
668 | # define malloc_getpagesize PAGESIZE | |
669 | # else | |
670 | # define malloc_getpagesize (4096) /* just guess */ | |
671 | # endif | |
672 | # endif | |
673 | # endif | |
674 | # endif | |
675 | # endif | |
676 | # endif | |
677 | #endif | |
678 | ||
679 | ||
680 | ||
681 | /* | |
682 | ||
683 | This version of malloc supports the standard SVID/XPG mallinfo | |
684 | routine that returns a struct containing the same kind of | |
685 | information you can get from malloc_stats. It should work on | |
686 | any SVID/XPG compliant system that has a /usr/include/malloc.h | |
687 | defining struct mallinfo. (If you'd like to install such a thing | |
688 | yourself, cut out the preliminary declarations as described above | |
689 | and below and save them in a malloc.h file. But there's no | |
690 | compelling reason to bother to do this.) | |
691 | ||
692 | The main declaration needed is the mallinfo struct that is returned | |
693 | (by-copy) by mallinfo(). The SVID/XPG malloinfo struct contains a | |
694 | bunch of fields, most of which are not even meaningful in this | |
695 | version of malloc. Some of these fields are are instead filled by | |
696 | mallinfo() with other numbers that might possibly be of interest. | |
697 | ||
698 | HAVE_USR_INCLUDE_MALLOC_H should be set if you have a | |
699 | /usr/include/malloc.h file that includes a declaration of struct | |
700 | mallinfo. If so, it is included; else an SVID2/XPG2 compliant | |
701 | version is declared below. These must be precisely the same for | |
702 | mallinfo() to work. | |
703 | ||
704 | */ | |
705 | ||
706 | /* #define HAVE_USR_INCLUDE_MALLOC_H */ | |
707 | ||
708 | #if HAVE_USR_INCLUDE_MALLOC_H | |
709 | #include "/usr/include/malloc.h" | |
710 | #else | |
711 | ||
712 | /* SVID2/XPG mallinfo structure */ | |
713 | ||
714 | struct mallinfo { | |
715 | int arena; /* total space allocated from system */ | |
716 | int ordblks; /* number of non-inuse chunks */ | |
717 | int smblks; /* unused -- always zero */ | |
718 | int hblks; /* number of mmapped regions */ | |
719 | int hblkhd; /* total space in mmapped regions */ | |
720 | int usmblks; /* unused -- always zero */ | |
721 | int fsmblks; /* unused -- always zero */ | |
722 | int uordblks; /* total allocated space */ | |
723 | int fordblks; /* total non-inuse space */ | |
724 | int keepcost; /* top-most, releasable (via malloc_trim) space */ | |
725 | }; | |
726 | ||
727 | /* SVID2/XPG mallopt options */ | |
728 | ||
729 | #define M_MXFAST 1 /* UNUSED in this malloc */ | |
730 | #define M_NLBLKS 2 /* UNUSED in this malloc */ | |
731 | #define M_GRAIN 3 /* UNUSED in this malloc */ | |
732 | #define M_KEEP 4 /* UNUSED in this malloc */ | |
733 | ||
734 | #endif | |
735 | ||
736 | /* mallopt options that actually do something */ | |
737 | ||
738 | #define M_TRIM_THRESHOLD -1 | |
739 | #define M_TOP_PAD -2 | |
740 | #define M_MMAP_THRESHOLD -3 | |
741 | #define M_MMAP_MAX -4 | |
742 | ||
743 | ||
744 | ||
745 | #ifndef DEFAULT_TRIM_THRESHOLD | |
746 | #define DEFAULT_TRIM_THRESHOLD (128L * 1024L) | |
747 | #endif | |
748 | ||
749 | /* | |
750 | M_TRIM_THRESHOLD is the maximum amount of unused top-most memory | |
751 | to keep before releasing via malloc_trim in free(). | |
752 | ||
753 | Automatic trimming is mainly useful in long-lived programs. | |
754 | Because trimming via sbrk can be slow on some systems, and can | |
755 | sometimes be wasteful (in cases where programs immediately | |
756 | afterward allocate more large chunks) the value should be high | |
757 | enough so that your overall system performance would improve by | |
758 | releasing. | |
759 | ||
760 | The trim threshold and the mmap control parameters (see below) | |
761 | can be traded off with one another. Trimming and mmapping are | |
762 | two different ways of releasing unused memory back to the | |
763 | system. Between these two, it is often possible to keep | |
764 | system-level demands of a long-lived program down to a bare | |
765 | minimum. For example, in one test suite of sessions measuring | |
766 | the XF86 X server on Linux, using a trim threshold of 128K and a | |
767 | mmap threshold of 192K led to near-minimal long term resource | |
768 | consumption. | |
769 | ||
770 | If you are using this malloc in a long-lived program, it should | |
771 | pay to experiment with these values. As a rough guide, you | |
772 | might set to a value close to the average size of a process | |
773 | (program) running on your system. Releasing this much memory | |
774 | would allow such a process to run in memory. Generally, it's | |
775 | worth it to tune for trimming rather tham memory mapping when a | |
776 | program undergoes phases where several large chunks are | |
777 | allocated and released in ways that can reuse each other's | |
778 | storage, perhaps mixed with phases where there are no such | |
779 | chunks at all. And in well-behaved long-lived programs, | |
780 | controlling release of large blocks via trimming versus mapping | |
781 | is usually faster. | |
782 | ||
783 | However, in most programs, these parameters serve mainly as | |
784 | protection against the system-level effects of carrying around | |
785 | massive amounts of unneeded memory. Since frequent calls to | |
786 | sbrk, mmap, and munmap otherwise degrade performance, the default | |
787 | parameters are set to relatively high values that serve only as | |
788 | safeguards. | |
789 | ||
790 | The default trim value is high enough to cause trimming only in | |
791 | fairly extreme (by current memory consumption standards) cases. | |
792 | It must be greater than page size to have any useful effect. To | |
793 | disable trimming completely, you can set to (unsigned long)(-1); | |
794 | ||
795 | ||
796 | */ | |
797 | ||
798 | ||
799 | #ifndef DEFAULT_TOP_PAD | |
800 | #define DEFAULT_TOP_PAD (0) | |
801 | #endif | |
802 | ||
803 | /* | |
804 | M_TOP_PAD is the amount of extra `padding' space to allocate or | |
805 | retain whenever sbrk is called. It is used in two ways internally: | |
806 | ||
807 | * When sbrk is called to extend the top of the arena to satisfy | |
808 | a new malloc request, this much padding is added to the sbrk | |
809 | request. | |
810 | ||
811 | * When malloc_trim is called automatically from free(), | |
812 | it is used as the `pad' argument. | |
813 | ||
814 | In both cases, the actual amount of padding is rounded | |
815 | so that the end of the arena is always a system page boundary. | |
816 | ||
817 | The main reason for using padding is to avoid calling sbrk so | |
818 | often. Having even a small pad greatly reduces the likelihood | |
819 | that nearly every malloc request during program start-up (or | |
820 | after trimming) will invoke sbrk, which needlessly wastes | |
821 | time. | |
822 | ||
823 | Automatic rounding-up to page-size units is normally sufficient | |
824 | to avoid measurable overhead, so the default is 0. However, in | |
825 | systems where sbrk is relatively slow, it can pay to increase | |
826 | this value, at the expense of carrying around more memory than | |
827 | the program needs. | |
828 | ||
829 | */ | |
830 | ||
831 | ||
832 | #ifndef DEFAULT_MMAP_THRESHOLD | |
833 | #define DEFAULT_MMAP_THRESHOLD (128 * 1024) | |
834 | #endif | |
835 | ||
836 | /* | |
837 | ||
838 | M_MMAP_THRESHOLD is the request size threshold for using mmap() | |
839 | to service a request. Requests of at least this size that cannot | |
840 | be allocated using already-existing space will be serviced via mmap. | |
841 | (If enough normal freed space already exists it is used instead.) | |
842 | ||
843 | Using mmap segregates relatively large chunks of memory so that | |
844 | they can be individually obtained and released from the host | |
845 | system. A request serviced through mmap is never reused by any | |
846 | other request (at least not directly; the system may just so | |
847 | happen to remap successive requests to the same locations). | |
848 | ||
849 | Segregating space in this way has the benefit that mmapped space | |
850 | can ALWAYS be individually released back to the system, which | |
851 | helps keep the system level memory demands of a long-lived | |
852 | program low. Mapped memory can never become `locked' between | |
853 | other chunks, as can happen with normally allocated chunks, which | |
854 | menas that even trimming via malloc_trim would not release them. | |
855 | ||
856 | However, it has the disadvantages that: | |
857 | ||
858 | 1. The space cannot be reclaimed, consolidated, and then | |
859 | used to service later requests, as happens with normal chunks. | |
860 | 2. It can lead to more wastage because of mmap page alignment | |
861 | requirements | |
862 | 3. It causes malloc performance to be more dependent on host | |
863 | system memory management support routines which may vary in | |
864 | implementation quality and may impose arbitrary | |
865 | limitations. Generally, servicing a request via normal | |
866 | malloc steps is faster than going through a system's mmap. | |
867 | ||
868 | All together, these considerations should lead you to use mmap | |
869 | only for relatively large requests. | |
870 | ||
871 | ||
872 | */ | |
873 | ||
874 | ||
875 | ||
876 | #ifndef DEFAULT_MMAP_MAX | |
877 | #if HAVE_MMAP | |
878 | #define DEFAULT_MMAP_MAX (64) | |
879 | #else | |
880 | #define DEFAULT_MMAP_MAX (0) | |
881 | #endif | |
882 | #endif | |
883 | ||
884 | /* | |
885 | M_MMAP_MAX is the maximum number of requests to simultaneously | |
886 | service using mmap. This parameter exists because: | |
887 | ||
888 | 1. Some systems have a limited number of internal tables for | |
889 | use by mmap. | |
890 | 2. In most systems, overreliance on mmap can degrade overall | |
891 | performance. | |
892 | 3. If a program allocates many large regions, it is probably | |
893 | better off using normal sbrk-based allocation routines that | |
894 | can reclaim and reallocate normal heap memory. Using a | |
895 | small value allows transition into this mode after the | |
896 | first few allocations. | |
897 | ||
898 | Setting to 0 disables all use of mmap. If HAVE_MMAP is not set, | |
899 | the default value is 0, and attempts to set it to non-zero values | |
900 | in mallopt will fail. | |
901 | */ | |
902 | ||
903 | ||
904 | ||
905 | ||
906 | /* | |
907 | ||
908 | Special defines for linux libc | |
909 | ||
910 | Except when compiled using these special defines for Linux libc | |
911 | using weak aliases, this malloc is NOT designed to work in | |
912 | multithreaded applications. No semaphores or other concurrency | |
913 | control are provided to ensure that multiple malloc or free calls | |
914 | don't run at the same time, which could be disasterous. A single | |
915 | semaphore could be used across malloc, realloc, and free (which is | |
916 | essentially the effect of the linux weak alias approach). It would | |
917 | be hard to obtain finer granularity. | |
918 | ||
919 | */ | |
920 | ||
921 | ||
922 | #ifdef INTERNAL_LINUX_C_LIB | |
923 | ||
924 | #if __STD_C | |
925 | ||
926 | Void_t * __default_morecore_init (ptrdiff_t); | |
927 | Void_t *(*__morecore)(ptrdiff_t) = __default_morecore_init; | |
928 | ||
929 | #else | |
930 | ||
931 | Void_t * __default_morecore_init (); | |
932 | Void_t *(*__morecore)() = __default_morecore_init; | |
933 | ||
934 | #endif | |
935 | ||
936 | #define MORECORE (*__morecore) | |
937 | #define MORECORE_FAILURE 0 | |
938 | #define MORECORE_CLEARS 1 | |
939 | ||
940 | #else /* INTERNAL_LINUX_C_LIB */ | |
941 | ||
942 | #ifndef INTERNAL_NEWLIB | |
943 | #if __STD_C | |
944 | extern Void_t* sbrk(ptrdiff_t); | |
945 | #else | |
946 | extern Void_t* sbrk(); | |
947 | #endif | |
948 | #endif | |
949 | ||
950 | #ifndef MORECORE | |
951 | #define MORECORE sbrk | |
952 | #endif | |
953 | ||
954 | #ifndef MORECORE_FAILURE | |
955 | #define MORECORE_FAILURE -1 | |
956 | #endif | |
957 | ||
958 | #ifndef MORECORE_CLEARS | |
959 | #define MORECORE_CLEARS 1 | |
960 | #endif | |
961 | ||
962 | #endif /* INTERNAL_LINUX_C_LIB */ | |
963 | ||
964 | #if defined(INTERNAL_LINUX_C_LIB) && defined(__ELF__) | |
965 | ||
966 | #define cALLOc __libc_calloc | |
967 | #define fREe __libc_free | |
968 | #define mALLOc __libc_malloc | |
969 | #define mEMALIGn __libc_memalign | |
970 | #define rEALLOc __libc_realloc | |
971 | #define vALLOc __libc_valloc | |
972 | #define pvALLOc __libc_pvalloc | |
973 | #define mALLINFo __libc_mallinfo | |
974 | #define mALLOPt __libc_mallopt | |
975 | ||
976 | #pragma weak calloc = __libc_calloc | |
977 | #pragma weak free = __libc_free | |
978 | #pragma weak cfree = __libc_free | |
979 | #pragma weak malloc = __libc_malloc | |
980 | #pragma weak memalign = __libc_memalign | |
981 | #pragma weak realloc = __libc_realloc | |
982 | #pragma weak valloc = __libc_valloc | |
983 | #pragma weak pvalloc = __libc_pvalloc | |
984 | #pragma weak mallinfo = __libc_mallinfo | |
985 | #pragma weak mallopt = __libc_mallopt | |
986 | ||
987 | #else | |
988 | ||
989 | #ifdef INTERNAL_NEWLIB | |
990 | ||
991 | #define cALLOc _calloc_r | |
992 | #define fREe _free_r | |
993 | #define mALLOc _malloc_r | |
994 | #define mEMALIGn _memalign_r | |
995 | #define rEALLOc _realloc_r | |
996 | #define vALLOc _valloc_r | |
997 | #define pvALLOc _pvalloc_r | |
998 | #define mALLINFo _mallinfo_r | |
999 | #define mALLOPt _mallopt_r | |
1000 | ||
1001 | #define malloc_stats _malloc_stats_r | |
1002 | #define malloc_trim _malloc_trim_r | |
1003 | #define malloc_usable_size _malloc_usable_size_r | |
1004 | ||
1005 | #define malloc_update_mallinfo __malloc_update_mallinfo | |
1006 | ||
1007 | #define malloc_av_ __malloc_av_ | |
1008 | #define malloc_current_mallinfo __malloc_current_mallinfo | |
1009 | #define malloc_max_sbrked_mem __malloc_max_sbrked_mem | |
1010 | #define malloc_max_total_mem __malloc_max_total_mem | |
1011 | #define malloc_sbrk_base __malloc_sbrk_base | |
1012 | #define malloc_top_pad __malloc_top_pad | |
1013 | #define malloc_trim_threshold __malloc_trim_threshold | |
1014 | ||
1015 | #else /* ! INTERNAL_NEWLIB */ | |
1016 | ||
1017 | #define cALLOc calloc | |
1018 | #define fREe free | |
1019 | #define mALLOc malloc | |
1020 | #define mEMALIGn memalign | |
1021 | #define rEALLOc realloc | |
1022 | #define vALLOc valloc | |
1023 | #define pvALLOc pvalloc | |
1024 | #define mALLINFo mallinfo | |
1025 | #define mALLOPt mallopt | |
1026 | ||
1027 | #endif /* ! INTERNAL_NEWLIB */ | |
1028 | #endif | |
1029 | ||
1030 | /* Public routines */ | |
1031 | ||
1032 | #if __STD_C | |
1033 | ||
1034 | Void_t* mALLOc(RARG size_t); | |
1035 | void fREe(RARG Void_t*); | |
1036 | Void_t* rEALLOc(RARG Void_t*, size_t); | |
1037 | Void_t* mEMALIGn(RARG size_t, size_t); | |
1038 | Void_t* vALLOc(RARG size_t); | |
1039 | Void_t* pvALLOc(RARG size_t); | |
1040 | Void_t* cALLOc(RARG size_t, size_t); | |
1041 | void cfree(Void_t*); | |
1042 | int malloc_trim(RARG size_t); | |
1043 | size_t malloc_usable_size(RARG Void_t*); | |
1044 | void malloc_stats(RONEARG); | |
1045 | int mALLOPt(RARG int, int); | |
1046 | struct mallinfo mALLINFo(RONEARG); | |
1047 | #else | |
1048 | Void_t* mALLOc(); | |
1049 | void fREe(); | |
1050 | Void_t* rEALLOc(); | |
1051 | Void_t* mEMALIGn(); | |
1052 | Void_t* vALLOc(); | |
1053 | Void_t* pvALLOc(); | |
1054 | Void_t* cALLOc(); | |
1055 | void cfree(); | |
1056 | int malloc_trim(); | |
1057 | size_t malloc_usable_size(); | |
1058 | void malloc_stats(); | |
1059 | int mALLOPt(); | |
1060 | struct mallinfo mALLINFo(); | |
1061 | #endif | |
1062 | ||
1063 | ||
1064 | #ifdef __cplusplus | |
1065 | }; /* end of extern "C" */ | |
1066 | #endif | |
1067 | ||
1068 | /* ---------- To make a malloc.h, end cutting here ------------ */ | |
1069 | ||
1070 | ||
1071 | /* | |
1072 | Emulation of sbrk for WIN32 | |
1073 | All code within the ifdef WIN32 is untested by me. | |
1074 | */ | |
1075 | ||
1076 | ||
1077 | #ifdef WIN32 | |
1078 | ||
fe47ea33 | 1079 | #define AlignPage(add) (((add) + (malloc_getpagesize-1)) & \ |
8a0efa53 CF |
1080 | ~(malloc_getpagesize-1)) |
1081 | ||
1082 | /* resrve 64MB to insure large contiguous space */ | |
1083 | #define RESERVED_SIZE (1024*1024*64) | |
1084 | #define NEXT_SIZE (2048*1024) | |
1085 | #define TOP_MEMORY ((unsigned long)2*1024*1024*1024) | |
1086 | ||
1087 | struct GmListElement; | |
1088 | typedef struct GmListElement GmListElement; | |
1089 | ||
1090 | struct GmListElement | |
1091 | { | |
1092 | GmListElement* next; | |
1093 | void* base; | |
1094 | }; | |
1095 | ||
1096 | static GmListElement* head = 0; | |
1097 | static unsigned int gNextAddress = 0; | |
1098 | static unsigned int gAddressBase = 0; | |
1099 | static unsigned int gAllocatedSize = 0; | |
1100 | ||
1101 | static | |
1102 | GmListElement* makeGmListElement (void* bas) | |
1103 | { | |
1104 | GmListElement* this; | |
1105 | this = (GmListElement*)(void*)LocalAlloc (0, sizeof (GmListElement)); | |
1106 | ASSERT (this); | |
1107 | if (this) | |
1108 | { | |
1109 | this->base = bas; | |
1110 | this->next = head; | |
1111 | head = this; | |
1112 | } | |
1113 | return this; | |
1114 | } | |
1115 | ||
1116 | void gcleanup () | |
1117 | { | |
1118 | BOOL rval; | |
1119 | ASSERT ( (head == NULL) || (head->base == (void*)gAddressBase)); | |
1120 | if (gAddressBase && (gNextAddress - gAddressBase)) | |
1121 | { | |
1122 | rval = VirtualFree ((void*)gAddressBase, | |
1123 | gNextAddress - gAddressBase, | |
1124 | MEM_DECOMMIT); | |
1125 | ASSERT (rval); | |
1126 | } | |
1127 | while (head) | |
1128 | { | |
1129 | GmListElement* next = head->next; | |
1130 | rval = VirtualFree (head->base, 0, MEM_RELEASE); | |
1131 | ASSERT (rval); | |
1132 | LocalFree (head); | |
1133 | head = next; | |
1134 | } | |
1135 | } | |
1136 | ||
1137 | static | |
1138 | void* findRegion (void* start_address, unsigned long size) | |
1139 | { | |
1140 | MEMORY_BASIC_INFORMATION info; | |
1141 | while ((unsigned long)start_address < TOP_MEMORY) | |
1142 | { | |
1143 | VirtualQuery (start_address, &info, sizeof (info)); | |
1144 | if (info.State != MEM_FREE) | |
1145 | start_address = (char*)info.BaseAddress + info.RegionSize; | |
1146 | else if (info.RegionSize >= size) | |
1147 | return start_address; | |
1148 | else | |
1149 | start_address = (char*)info.BaseAddress + info.RegionSize; | |
1150 | } | |
1151 | return NULL; | |
1152 | ||
1153 | } | |
1154 | ||
1155 | ||
1156 | void* wsbrk (long size) | |
1157 | { | |
1158 | void* tmp; | |
1159 | if (size > 0) | |
1160 | { | |
1161 | if (gAddressBase == 0) | |
1162 | { | |
1163 | gAllocatedSize = max (RESERVED_SIZE, AlignPage (size)); | |
1164 | gNextAddress = gAddressBase = | |
1165 | (unsigned int)VirtualAlloc (NULL, gAllocatedSize, | |
1166 | MEM_RESERVE, PAGE_NOACCESS); | |
1167 | } else if (AlignPage (gNextAddress + size) > (gAddressBase + | |
1168 | gAllocatedSize)) | |
1169 | { | |
1170 | long new_size = max (NEXT_SIZE, AlignPage (size)); | |
1171 | void* new_address = (void*)(gAddressBase+gAllocatedSize); | |
1172 | do | |
1173 | { | |
1174 | new_address = findRegion (new_address, new_size); | |
1175 | ||
1176 | if (new_address == 0) | |
1177 | return (void*)-1; | |
1178 | ||
1179 | gAddressBase = gNextAddress = | |
1180 | (unsigned int)VirtualAlloc (new_address, new_size, | |
1181 | MEM_RESERVE, PAGE_NOACCESS); | |
1182 | // repeat in case of race condition | |
1183 | // The region that we found has been snagged | |
1184 | // by another thread | |
1185 | } | |
1186 | while (gAddressBase == 0); | |
1187 | ||
1188 | ASSERT (new_address == (void*)gAddressBase); | |
1189 | ||
1190 | gAllocatedSize = new_size; | |
1191 | ||
1192 | if (!makeGmListElement ((void*)gAddressBase)) | |
1193 | return (void*)-1; | |
1194 | } | |
1195 | if ((size + gNextAddress) > AlignPage (gNextAddress)) | |
1196 | { | |
1197 | void* res; | |
1198 | res = VirtualAlloc ((void*)AlignPage (gNextAddress), | |
1199 | (size + gNextAddress - | |
1200 | AlignPage (gNextAddress)), | |
1201 | MEM_COMMIT, PAGE_READWRITE); | |
1202 | if (res == 0) | |
1203 | return (void*)-1; | |
1204 | } | |
1205 | tmp = (void*)gNextAddress; | |
1206 | gNextAddress = (unsigned int)tmp + size; | |
1207 | return tmp; | |
1208 | } | |
1209 | else if (size < 0) | |
1210 | { | |
1211 | unsigned int alignedGoal = AlignPage (gNextAddress + size); | |
1212 | /* Trim by releasing the virtual memory */ | |
1213 | if (alignedGoal >= gAddressBase) | |
1214 | { | |
1215 | VirtualFree ((void*)alignedGoal, gNextAddress - alignedGoal, | |
1216 | MEM_DECOMMIT); | |
1217 | gNextAddress = gNextAddress + size; | |
1218 | return (void*)gNextAddress; | |
1219 | } | |
1220 | else | |
1221 | { | |
1222 | VirtualFree ((void*)gAddressBase, gNextAddress - gAddressBase, | |
1223 | MEM_DECOMMIT); | |
1224 | gNextAddress = gAddressBase; | |
1225 | return (void*)-1; | |
1226 | } | |
1227 | } | |
1228 | else | |
1229 | { | |
1230 | return (void*)gNextAddress; | |
1231 | } | |
1232 | } | |
1233 | ||
1234 | #endif | |
1235 | ||
1236 | \f | |
1237 | ||
1238 | /* | |
1239 | Type declarations | |
1240 | */ | |
1241 | ||
1242 | ||
1243 | struct malloc_chunk | |
1244 | { | |
1245 | INTERNAL_SIZE_T prev_size; /* Size of previous chunk (if free). */ | |
1246 | INTERNAL_SIZE_T size; /* Size in bytes, including overhead. */ | |
1247 | struct malloc_chunk* fd; /* double links -- used only if free. */ | |
1248 | struct malloc_chunk* bk; | |
1249 | }; | |
1250 | ||
1251 | typedef struct malloc_chunk* mchunkptr; | |
1252 | ||
1253 | /* | |
1254 | ||
1255 | malloc_chunk details: | |
1256 | ||
1257 | (The following includes lightly edited explanations by Colin Plumb.) | |
1258 | ||
1259 | Chunks of memory are maintained using a `boundary tag' method as | |
1260 | described in e.g., Knuth or Standish. (See the paper by Paul | |
1261 | Wilson ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a | |
1262 | survey of such techniques.) Sizes of free chunks are stored both | |
1263 | in the front of each chunk and at the end. This makes | |
1264 | consolidating fragmented chunks into bigger chunks very fast. The | |
1265 | size fields also hold bits representing whether chunks are free or | |
1266 | in use. | |
1267 | ||
1268 | An allocated chunk looks like this: | |
1269 | ||
1270 | ||
1271 | chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1272 | | Size of previous chunk, if allocated | | | |
1273 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1274 | | Size of chunk, in bytes |P| | |
1275 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1276 | | User data starts here... . | |
1277 | . . | |
1278 | . (malloc_usable_space() bytes) . | |
1279 | . | | |
1280 | nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1281 | | Size of chunk | | |
1282 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1283 | ||
1284 | ||
1285 | Where "chunk" is the front of the chunk for the purpose of most of | |
1286 | the malloc code, but "mem" is the pointer that is returned to the | |
1287 | user. "Nextchunk" is the beginning of the next contiguous chunk. | |
1288 | ||
1289 | Chunks always begin on even word boundries, so the mem portion | |
1290 | (which is returned to the user) is also on an even word boundary, and | |
1291 | thus double-word aligned. | |
1292 | ||
1293 | Free chunks are stored in circular doubly-linked lists, and look like this: | |
1294 | ||
1295 | chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1296 | | Size of previous chunk | | |
1297 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1298 | `head:' | Size of chunk, in bytes |P| | |
1299 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1300 | | Forward pointer to next chunk in list | | |
1301 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1302 | | Back pointer to previous chunk in list | | |
1303 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1304 | | Unused space (may be 0 bytes long) . | |
1305 | . . | |
1306 | . | | |
1307 | nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1308 | `foot:' | Size of chunk, in bytes | | |
1309 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
1310 | ||
1311 | The P (PREV_INUSE) bit, stored in the unused low-order bit of the | |
1312 | chunk size (which is always a multiple of two words), is an in-use | |
1313 | bit for the *previous* chunk. If that bit is *clear*, then the | |
1314 | word before the current chunk size contains the previous chunk | |
1315 | size, and can be used to find the front of the previous chunk. | |
1316 | (The very first chunk allocated always has this bit set, | |
1317 | preventing access to non-existent (or non-owned) memory.) | |
1318 | ||
1319 | Note that the `foot' of the current chunk is actually represented | |
1320 | as the prev_size of the NEXT chunk. (This makes it easier to | |
1321 | deal with alignments etc). | |
1322 | ||
1323 | The two exceptions to all this are | |
1324 | ||
1325 | 1. The special chunk `top', which doesn't bother using the | |
1326 | trailing size field since there is no | |
1327 | next contiguous chunk that would have to index off it. (After | |
1328 | initialization, `top' is forced to always exist. If it would | |
1329 | become less than MINSIZE bytes long, it is replenished via | |
1330 | malloc_extend_top.) | |
1331 | ||
1332 | 2. Chunks allocated via mmap, which have the second-lowest-order | |
1333 | bit (IS_MMAPPED) set in their size fields. Because they are | |
1334 | never merged or traversed from any other chunk, they have no | |
1335 | foot size or inuse information. | |
1336 | ||
1337 | Available chunks are kept in any of several places (all declared below): | |
1338 | ||
1339 | * `av': An array of chunks serving as bin headers for consolidated | |
1340 | chunks. Each bin is doubly linked. The bins are approximately | |
1341 | proportionally (log) spaced. There are a lot of these bins | |
1342 | (128). This may look excessive, but works very well in | |
1343 | practice. All procedures maintain the invariant that no | |
1344 | consolidated chunk physically borders another one. Chunks in | |
1345 | bins are kept in size order, with ties going to the | |
1346 | approximately least recently used chunk. | |
1347 | ||
1348 | The chunks in each bin are maintained in decreasing sorted order by | |
1349 | size. This is irrelevant for the small bins, which all contain | |
1350 | the same-sized chunks, but facilitates best-fit allocation for | |
1351 | larger chunks. (These lists are just sequential. Keeping them in | |
1352 | order almost never requires enough traversal to warrant using | |
1353 | fancier ordered data structures.) Chunks of the same size are | |
1354 | linked with the most recently freed at the front, and allocations | |
1355 | are taken from the back. This results in LRU or FIFO allocation | |
1356 | order, which tends to give each chunk an equal opportunity to be | |
1357 | consolidated with adjacent freed chunks, resulting in larger free | |
1358 | chunks and less fragmentation. | |
1359 | ||
1360 | * `top': The top-most available chunk (i.e., the one bordering the | |
1361 | end of available memory) is treated specially. It is never | |
1362 | included in any bin, is used only if no other chunk is | |
1363 | available, and is released back to the system if it is very | |
1364 | large (see M_TRIM_THRESHOLD). | |
1365 | ||
1366 | * `last_remainder': A bin holding only the remainder of the | |
1367 | most recently split (non-top) chunk. This bin is checked | |
1368 | before other non-fitting chunks, so as to provide better | |
1369 | locality for runs of sequentially allocated chunks. | |
1370 | ||
1371 | * Implicitly, through the host system's memory mapping tables. | |
1372 | If supported, requests greater than a threshold are usually | |
1373 | serviced via calls to mmap, and then later released via munmap. | |
1374 | ||
1375 | */ | |
1376 | ||
1377 | ||
1378 | ||
1379 | \f | |
1380 | ||
1381 | ||
1382 | /* sizes, alignments */ | |
1383 | ||
1384 | #define SIZE_SZ (sizeof(INTERNAL_SIZE_T)) | |
1385 | #ifndef MALLOC_ALIGNMENT | |
1386 | #define MALLOC_ALIGN 8 | |
e8267664 | 1387 | #define MALLOC_ALIGNMENT (SIZE_SZ < 4 ? 8 : (SIZE_SZ + SIZE_SZ)) |
8a0efa53 CF |
1388 | #else |
1389 | #define MALLOC_ALIGN MALLOC_ALIGNMENT | |
1390 | #endif | |
1391 | #define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1) | |
1392 | #define MINSIZE (sizeof(struct malloc_chunk)) | |
1393 | ||
1394 | /* conversion from malloc headers to user pointers, and back */ | |
1395 | ||
1396 | #define chunk2mem(p) ((Void_t*)((char*)(p) + 2*SIZE_SZ)) | |
1397 | #define mem2chunk(mem) ((mchunkptr)((char*)(mem) - 2*SIZE_SZ)) | |
1398 | ||
1399 | /* pad request bytes into a usable size */ | |
1400 | ||
1401 | #define request2size(req) \ | |
659e7062 JJ |
1402 | (((unsigned long)((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) < \ |
1403 | (unsigned long)(MINSIZE + MALLOC_ALIGN_MASK)) ? ((MINSIZE + MALLOC_ALIGN_MASK) & ~(MALLOC_ALIGN_MASK)) : \ | |
8a0efa53 CF |
1404 | (((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) & ~(MALLOC_ALIGN_MASK))) |
1405 | ||
1406 | /* Check if m has acceptable alignment */ | |
1407 | ||
1408 | #define aligned_OK(m) (((unsigned long)((m)) & (MALLOC_ALIGN_MASK)) == 0) | |
1409 | ||
1410 | ||
1411 | \f | |
1412 | ||
1413 | /* | |
1414 | Physical chunk operations | |
1415 | */ | |
1416 | ||
1417 | ||
1418 | /* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */ | |
1419 | ||
1420 | #define PREV_INUSE 0x1 | |
1421 | ||
1422 | /* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */ | |
1423 | ||
1424 | #define IS_MMAPPED 0x2 | |
1425 | ||
1426 | /* Bits to mask off when extracting size */ | |
1427 | ||
1428 | #define SIZE_BITS (PREV_INUSE|IS_MMAPPED) | |
1429 | ||
1430 | ||
1431 | /* Ptr to next physical malloc_chunk. */ | |
1432 | ||
1433 | #define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->size & ~PREV_INUSE) )) | |
1434 | ||
1435 | /* Ptr to previous physical malloc_chunk */ | |
1436 | ||
1437 | #define prev_chunk(p)\ | |
1438 | ((mchunkptr)( ((char*)(p)) - ((p)->prev_size) )) | |
1439 | ||
1440 | ||
1441 | /* Treat space at ptr + offset as a chunk */ | |
1442 | ||
1443 | #define chunk_at_offset(p, s) ((mchunkptr)(((char*)(p)) + (s))) | |
1444 | ||
1445 | ||
1446 | \f | |
1447 | ||
1448 | /* | |
1449 | Dealing with use bits | |
1450 | */ | |
1451 | ||
1452 | /* extract p's inuse bit */ | |
1453 | ||
1454 | #define inuse(p)\ | |
1455 | ((((mchunkptr)(((char*)(p))+((p)->size & ~PREV_INUSE)))->size) & PREV_INUSE) | |
1456 | ||
1457 | /* extract inuse bit of previous chunk */ | |
1458 | ||
1459 | #define prev_inuse(p) ((p)->size & PREV_INUSE) | |
1460 | ||
1461 | /* check for mmap()'ed chunk */ | |
1462 | ||
1463 | #define chunk_is_mmapped(p) ((p)->size & IS_MMAPPED) | |
1464 | ||
1465 | /* set/clear chunk as in use without otherwise disturbing */ | |
1466 | ||
1467 | #define set_inuse(p)\ | |
1468 | ((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size |= PREV_INUSE | |
1469 | ||
1470 | #define clear_inuse(p)\ | |
1471 | ((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size &= ~(PREV_INUSE) | |
1472 | ||
1473 | /* check/set/clear inuse bits in known places */ | |
1474 | ||
1475 | #define inuse_bit_at_offset(p, s)\ | |
1476 | (((mchunkptr)(((char*)(p)) + (s)))->size & PREV_INUSE) | |
1477 | ||
1478 | #define set_inuse_bit_at_offset(p, s)\ | |
1479 | (((mchunkptr)(((char*)(p)) + (s)))->size |= PREV_INUSE) | |
1480 | ||
1481 | #define clear_inuse_bit_at_offset(p, s)\ | |
1482 | (((mchunkptr)(((char*)(p)) + (s)))->size &= ~(PREV_INUSE)) | |
1483 | ||
1484 | ||
1485 | \f | |
1486 | ||
1487 | /* | |
1488 | Dealing with size fields | |
1489 | */ | |
1490 | ||
1491 | /* Get size, ignoring use bits */ | |
1492 | ||
1493 | #define chunksize(p) ((p)->size & ~(SIZE_BITS)) | |
1494 | ||
1495 | /* Set size at head, without disturbing its use bit */ | |
1496 | ||
1497 | #define set_head_size(p, s) ((p)->size = (((p)->size & PREV_INUSE) | (s))) | |
1498 | ||
1499 | /* Set size/use ignoring previous bits in header */ | |
1500 | ||
1501 | #define set_head(p, s) ((p)->size = (s)) | |
1502 | ||
1503 | /* Set size at footer (only when chunk is not in use) */ | |
1504 | ||
1505 | #define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_size = (s)) | |
1506 | ||
1507 | ||
1508 | \f | |
1509 | ||
1510 | ||
1511 | /* | |
1512 | Bins | |
1513 | ||
1514 | The bins, `av_' are an array of pairs of pointers serving as the | |
1515 | heads of (initially empty) doubly-linked lists of chunks, laid out | |
1516 | in a way so that each pair can be treated as if it were in a | |
1517 | malloc_chunk. (This way, the fd/bk offsets for linking bin heads | |
1518 | and chunks are the same). | |
1519 | ||
1520 | Bins for sizes < 512 bytes contain chunks of all the same size, spaced | |
1521 | 8 bytes apart. Larger bins are approximately logarithmically | |
1522 | spaced. (See the table below.) The `av_' array is never mentioned | |
1523 | directly in the code, but instead via bin access macros. | |
1524 | ||
1525 | Bin layout: | |
1526 | ||
1527 | 64 bins of size 8 | |
1528 | 32 bins of size 64 | |
1529 | 16 bins of size 512 | |
1530 | 8 bins of size 4096 | |
1531 | 4 bins of size 32768 | |
1532 | 2 bins of size 262144 | |
1533 | 1 bin of size what's left | |
1534 | ||
1535 | There is actually a little bit of slop in the numbers in bin_index | |
1536 | for the sake of speed. This makes no difference elsewhere. | |
1537 | ||
1538 | The special chunks `top' and `last_remainder' get their own bins, | |
1539 | (this is implemented via yet more trickery with the av_ array), | |
1540 | although `top' is never properly linked to its bin since it is | |
1541 | always handled specially. | |
1542 | ||
1543 | */ | |
1544 | ||
1545 | #ifdef SEPARATE_OBJECTS | |
1546 | #define av_ malloc_av_ | |
1547 | #endif | |
1548 | ||
1549 | #define NAV 128 /* number of bins */ | |
1550 | ||
1551 | typedef struct malloc_chunk* mbinptr; | |
1552 | ||
1553 | /* access macros */ | |
1554 | ||
1555 | #define bin_at(i) ((mbinptr)((char*)&(av_[2*(i) + 2]) - 2*SIZE_SZ)) | |
1556 | #define next_bin(b) ((mbinptr)((char*)(b) + 2 * sizeof(mbinptr))) | |
1557 | #define prev_bin(b) ((mbinptr)((char*)(b) - 2 * sizeof(mbinptr))) | |
1558 | ||
1559 | /* | |
1560 | The first 2 bins are never indexed. The corresponding av_ cells are instead | |
1561 | used for bookkeeping. This is not to save space, but to simplify | |
1562 | indexing, maintain locality, and avoid some initialization tests. | |
1563 | */ | |
1564 | ||
1565 | #define top (bin_at(0)->fd) /* The topmost chunk */ | |
1566 | #define last_remainder (bin_at(1)) /* remainder from last split */ | |
1567 | ||
1568 | ||
1569 | /* | |
1570 | Because top initially points to its own bin with initial | |
1571 | zero size, thus forcing extension on the first malloc request, | |
1572 | we avoid having any special code in malloc to check whether | |
1573 | it even exists yet. But we still need to in malloc_extend_top. | |
1574 | */ | |
1575 | ||
1576 | #define initial_top ((mchunkptr)(bin_at(0))) | |
1577 | ||
1578 | /* Helper macro to initialize bins */ | |
1579 | ||
1580 | #define IAV(i) bin_at(i), bin_at(i) | |
1581 | ||
1582 | #ifdef DEFINE_MALLOC | |
1583 | STATIC mbinptr av_[NAV * 2 + 2] = { | |
1584 | 0, 0, | |
1585 | IAV(0), IAV(1), IAV(2), IAV(3), IAV(4), IAV(5), IAV(6), IAV(7), | |
1586 | IAV(8), IAV(9), IAV(10), IAV(11), IAV(12), IAV(13), IAV(14), IAV(15), | |
1587 | IAV(16), IAV(17), IAV(18), IAV(19), IAV(20), IAV(21), IAV(22), IAV(23), | |
1588 | IAV(24), IAV(25), IAV(26), IAV(27), IAV(28), IAV(29), IAV(30), IAV(31), | |
1589 | IAV(32), IAV(33), IAV(34), IAV(35), IAV(36), IAV(37), IAV(38), IAV(39), | |
1590 | IAV(40), IAV(41), IAV(42), IAV(43), IAV(44), IAV(45), IAV(46), IAV(47), | |
1591 | IAV(48), IAV(49), IAV(50), IAV(51), IAV(52), IAV(53), IAV(54), IAV(55), | |
1592 | IAV(56), IAV(57), IAV(58), IAV(59), IAV(60), IAV(61), IAV(62), IAV(63), | |
1593 | IAV(64), IAV(65), IAV(66), IAV(67), IAV(68), IAV(69), IAV(70), IAV(71), | |
1594 | IAV(72), IAV(73), IAV(74), IAV(75), IAV(76), IAV(77), IAV(78), IAV(79), | |
1595 | IAV(80), IAV(81), IAV(82), IAV(83), IAV(84), IAV(85), IAV(86), IAV(87), | |
1596 | IAV(88), IAV(89), IAV(90), IAV(91), IAV(92), IAV(93), IAV(94), IAV(95), | |
1597 | IAV(96), IAV(97), IAV(98), IAV(99), IAV(100), IAV(101), IAV(102), IAV(103), | |
1598 | IAV(104), IAV(105), IAV(106), IAV(107), IAV(108), IAV(109), IAV(110), IAV(111), | |
1599 | IAV(112), IAV(113), IAV(114), IAV(115), IAV(116), IAV(117), IAV(118), IAV(119), | |
1600 | IAV(120), IAV(121), IAV(122), IAV(123), IAV(124), IAV(125), IAV(126), IAV(127) | |
1601 | }; | |
1602 | #else | |
1603 | extern mbinptr av_[NAV * 2 + 2]; | |
1604 | #endif | |
1605 | ||
1606 | \f | |
1607 | ||
1608 | /* field-extraction macros */ | |
1609 | ||
1610 | #define first(b) ((b)->fd) | |
1611 | #define last(b) ((b)->bk) | |
1612 | ||
1613 | /* | |
1614 | Indexing into bins | |
1615 | */ | |
1616 | ||
1617 | #define bin_index(sz) \ | |
1618 | (((((unsigned long)(sz)) >> 9) == 0) ? (((unsigned long)(sz)) >> 3): \ | |
1619 | ((((unsigned long)(sz)) >> 9) <= 4) ? 56 + (((unsigned long)(sz)) >> 6): \ | |
1620 | ((((unsigned long)(sz)) >> 9) <= 20) ? 91 + (((unsigned long)(sz)) >> 9): \ | |
1621 | ((((unsigned long)(sz)) >> 9) <= 84) ? 110 + (((unsigned long)(sz)) >> 12): \ | |
1622 | ((((unsigned long)(sz)) >> 9) <= 340) ? 119 + (((unsigned long)(sz)) >> 15): \ | |
1623 | ((((unsigned long)(sz)) >> 9) <= 1364) ? 124 + (((unsigned long)(sz)) >> 18): \ | |
1624 | 126) | |
1625 | /* | |
1626 | bins for chunks < 512 are all spaced SMALLBIN_WIDTH bytes apart, and hold | |
1627 | identically sized chunks. This is exploited in malloc. | |
1628 | */ | |
1629 | ||
1630 | #define MAX_SMALLBIN_SIZE 512 | |
1631 | #define SMALLBIN_WIDTH 8 | |
1632 | #define SMALLBIN_WIDTH_BITS 3 | |
1633 | #define MAX_SMALLBIN (MAX_SMALLBIN_SIZE / SMALLBIN_WIDTH) - 1 | |
1634 | ||
1635 | #define smallbin_index(sz) (((unsigned long)(sz)) >> SMALLBIN_WIDTH_BITS) | |
1636 | ||
1637 | /* | |
1638 | Requests are `small' if both the corresponding and the next bin are small | |
1639 | */ | |
1640 | ||
1641 | #define is_small_request(nb) (nb < MAX_SMALLBIN_SIZE - SMALLBIN_WIDTH) | |
1642 | ||
1643 | \f | |
1644 | ||
1645 | /* | |
1646 | To help compensate for the large number of bins, a one-level index | |
1647 | structure is used for bin-by-bin searching. `binblocks' is a | |
1648 | one-word bitvector recording whether groups of BINBLOCKWIDTH bins | |
1649 | have any (possibly) non-empty bins, so they can be skipped over | |
1650 | all at once during during traversals. The bits are NOT always | |
1651 | cleared as soon as all bins in a block are empty, but instead only | |
1652 | when all are noticed to be empty during traversal in malloc. | |
1653 | */ | |
1654 | ||
1655 | #define BINBLOCKWIDTH 4 /* bins per block */ | |
1656 | ||
1657 | #define binblocks (bin_at(0)->size) /* bitvector of nonempty blocks */ | |
1658 | ||
1659 | /* bin<->block macros */ | |
1660 | ||
1661 | #define idx2binblock(ix) ((unsigned long)1 << (ix / BINBLOCKWIDTH)) | |
1662 | #define mark_binblock(ii) (binblocks |= idx2binblock(ii)) | |
1663 | #define clear_binblock(ii) (binblocks &= ~(idx2binblock(ii))) | |
1664 | ||
1665 | ||
1666 | \f | |
1667 | ||
1668 | ||
1669 | /* Other static bookkeeping data */ | |
1670 | ||
1671 | #ifdef SEPARATE_OBJECTS | |
1672 | #define trim_threshold malloc_trim_threshold | |
1673 | #define top_pad malloc_top_pad | |
1674 | #define n_mmaps_max malloc_n_mmaps_max | |
1675 | #define mmap_threshold malloc_mmap_threshold | |
1676 | #define sbrk_base malloc_sbrk_base | |
1677 | #define max_sbrked_mem malloc_max_sbrked_mem | |
1678 | #define max_total_mem malloc_max_total_mem | |
1679 | #define current_mallinfo malloc_current_mallinfo | |
1680 | #define n_mmaps malloc_n_mmaps | |
1681 | #define max_n_mmaps malloc_max_n_mmaps | |
1682 | #define mmapped_mem malloc_mmapped_mem | |
1683 | #define max_mmapped_mem malloc_max_mmapped_mem | |
1684 | #endif | |
1685 | ||
1686 | /* variables holding tunable values */ | |
1687 | ||
1688 | #ifdef DEFINE_MALLOC | |
1689 | ||
1690 | STATIC unsigned long trim_threshold = DEFAULT_TRIM_THRESHOLD; | |
1691 | STATIC unsigned long top_pad = DEFAULT_TOP_PAD; | |
1692 | #if HAVE_MMAP | |
1693 | STATIC unsigned int n_mmaps_max = DEFAULT_MMAP_MAX; | |
1694 | STATIC unsigned long mmap_threshold = DEFAULT_MMAP_THRESHOLD; | |
1695 | #endif | |
1696 | ||
1697 | /* The first value returned from sbrk */ | |
1698 | STATIC char* sbrk_base = (char*)(-1); | |
1699 | ||
1700 | /* The maximum memory obtained from system via sbrk */ | |
1701 | STATIC unsigned long max_sbrked_mem = 0; | |
1702 | ||
1703 | /* The maximum via either sbrk or mmap */ | |
1704 | STATIC unsigned long max_total_mem = 0; | |
1705 | ||
1706 | /* internal working copy of mallinfo */ | |
1707 | STATIC struct mallinfo current_mallinfo = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; | |
1708 | ||
1709 | #if HAVE_MMAP | |
1710 | ||
1711 | /* Tracking mmaps */ | |
1712 | ||
1713 | STATIC unsigned int n_mmaps = 0; | |
1714 | STATIC unsigned int max_n_mmaps = 0; | |
1715 | STATIC unsigned long mmapped_mem = 0; | |
1716 | STATIC unsigned long max_mmapped_mem = 0; | |
1717 | ||
1718 | #endif | |
1719 | ||
1720 | #else /* ! DEFINE_MALLOC */ | |
1721 | ||
1722 | extern unsigned long trim_threshold; | |
1723 | extern unsigned long top_pad; | |
1724 | #if HAVE_MMAP | |
1725 | extern unsigned int n_mmaps_max; | |
1726 | extern unsigned long mmap_threshold; | |
1727 | #endif | |
1728 | extern char* sbrk_base; | |
1729 | extern unsigned long max_sbrked_mem; | |
1730 | extern unsigned long max_total_mem; | |
1731 | extern struct mallinfo current_mallinfo; | |
1732 | #if HAVE_MMAP | |
1733 | extern unsigned int n_mmaps; | |
1734 | extern unsigned int max_n_mmaps; | |
1735 | extern unsigned long mmapped_mem; | |
1736 | extern unsigned long max_mmapped_mem; | |
1737 | #endif | |
1738 | ||
1739 | #endif /* ! DEFINE_MALLOC */ | |
1740 | ||
1741 | /* The total memory obtained from system via sbrk */ | |
1742 | #define sbrked_mem (current_mallinfo.arena) | |
1743 | ||
1744 | \f | |
1745 | ||
1746 | /* | |
1747 | Debugging support | |
1748 | */ | |
1749 | ||
1750 | #if DEBUG | |
1751 | ||
1752 | ||
1753 | /* | |
1754 | These routines make a number of assertions about the states | |
1755 | of data structures that should be true at all times. If any | |
1756 | are not true, it's very likely that a user program has somehow | |
1757 | trashed memory. (It's also possible that there is a coding error | |
1758 | in malloc. In which case, please report it!) | |
1759 | */ | |
1760 | ||
1761 | #if __STD_C | |
1762 | static void do_check_chunk(mchunkptr p) | |
1763 | #else | |
1764 | static void do_check_chunk(p) mchunkptr p; | |
1765 | #endif | |
1766 | { | |
1767 | INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; | |
1768 | ||
1769 | /* No checkable chunk is mmapped */ | |
1770 | assert(!chunk_is_mmapped(p)); | |
1771 | ||
1772 | /* Check for legal address ... */ | |
1773 | assert((char*)p >= sbrk_base); | |
1774 | if (p != top) | |
1775 | assert((char*)p + sz <= (char*)top); | |
1776 | else | |
1777 | assert((char*)p + sz <= sbrk_base + sbrked_mem); | |
1778 | ||
1779 | } | |
1780 | ||
1781 | ||
1782 | #if __STD_C | |
1783 | static void do_check_free_chunk(mchunkptr p) | |
1784 | #else | |
1785 | static void do_check_free_chunk(p) mchunkptr p; | |
1786 | #endif | |
1787 | { | |
1788 | INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; | |
1789 | mchunkptr next = chunk_at_offset(p, sz); | |
1790 | ||
1791 | do_check_chunk(p); | |
1792 | ||
1793 | /* Check whether it claims to be free ... */ | |
1794 | assert(!inuse(p)); | |
1795 | ||
1796 | /* Unless a special marker, must have OK fields */ | |
1797 | if ((long)sz >= (long)MINSIZE) | |
1798 | { | |
1799 | assert((sz & MALLOC_ALIGN_MASK) == 0); | |
1800 | assert(aligned_OK(chunk2mem(p))); | |
1801 | /* ... matching footer field */ | |
1802 | assert(next->prev_size == sz); | |
1803 | /* ... and is fully consolidated */ | |
1804 | assert(prev_inuse(p)); | |
1805 | assert (next == top || inuse(next)); | |
1806 | ||
1807 | /* ... and has minimally sane links */ | |
1808 | assert(p->fd->bk == p); | |
1809 | assert(p->bk->fd == p); | |
1810 | } | |
1811 | else /* markers are always of size SIZE_SZ */ | |
1812 | assert(sz == SIZE_SZ); | |
1813 | } | |
1814 | ||
1815 | #if __STD_C | |
1816 | static void do_check_inuse_chunk(mchunkptr p) | |
1817 | #else | |
1818 | static void do_check_inuse_chunk(p) mchunkptr p; | |
1819 | #endif | |
1820 | { | |
1821 | mchunkptr next = next_chunk(p); | |
1822 | do_check_chunk(p); | |
1823 | ||
1824 | /* Check whether it claims to be in use ... */ | |
1825 | assert(inuse(p)); | |
1826 | ||
1827 | /* ... and is surrounded by OK chunks. | |
1828 | Since more things can be checked with free chunks than inuse ones, | |
1829 | if an inuse chunk borders them and debug is on, it's worth doing them. | |
1830 | */ | |
1831 | if (!prev_inuse(p)) | |
1832 | { | |
1833 | mchunkptr prv = prev_chunk(p); | |
1834 | assert(next_chunk(prv) == p); | |
1835 | do_check_free_chunk(prv); | |
1836 | } | |
1837 | if (next == top) | |
1838 | { | |
1839 | assert(prev_inuse(next)); | |
1840 | assert(chunksize(next) >= MINSIZE); | |
1841 | } | |
1842 | else if (!inuse(next)) | |
1843 | do_check_free_chunk(next); | |
1844 | ||
1845 | } | |
1846 | ||
1847 | #if __STD_C | |
1848 | static void do_check_malloced_chunk(mchunkptr p, INTERNAL_SIZE_T s) | |
1849 | #else | |
1850 | static void do_check_malloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s; | |
1851 | #endif | |
1852 | { | |
1853 | INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; | |
1854 | long room = long_sub_size_t(sz, s); | |
1855 | ||
1856 | do_check_inuse_chunk(p); | |
1857 | ||
1858 | /* Legal size ... */ | |
1859 | assert((long)sz >= (long)MINSIZE); | |
1860 | assert((sz & MALLOC_ALIGN_MASK) == 0); | |
1861 | assert(room >= 0); | |
1862 | assert(room < (long)MINSIZE); | |
1863 | ||
1864 | /* ... and alignment */ | |
1865 | assert(aligned_OK(chunk2mem(p))); | |
1866 | ||
1867 | ||
1868 | /* ... and was allocated at front of an available chunk */ | |
1869 | assert(prev_inuse(p)); | |
1870 | ||
1871 | } | |
1872 | ||
1873 | ||
1874 | #define check_free_chunk(P) do_check_free_chunk(P) | |
1875 | #define check_inuse_chunk(P) do_check_inuse_chunk(P) | |
1876 | #define check_chunk(P) do_check_chunk(P) | |
1877 | #define check_malloced_chunk(P,N) do_check_malloced_chunk(P,N) | |
1878 | #else | |
1879 | #define check_free_chunk(P) | |
1880 | #define check_inuse_chunk(P) | |
1881 | #define check_chunk(P) | |
1882 | #define check_malloced_chunk(P,N) | |
1883 | #endif | |
1884 | ||
1885 | \f | |
1886 | ||
1887 | /* | |
1888 | Macro-based internal utilities | |
1889 | */ | |
1890 | ||
1891 | ||
1892 | /* | |
1893 | Linking chunks in bin lists. | |
1894 | Call these only with variables, not arbitrary expressions, as arguments. | |
1895 | */ | |
1896 | ||
1897 | /* | |
1898 | Place chunk p of size s in its bin, in size order, | |
1899 | putting it ahead of others of same size. | |
1900 | */ | |
1901 | ||
1902 | ||
1903 | #define frontlink(P, S, IDX, BK, FD) \ | |
1904 | { \ | |
1905 | if (S < MAX_SMALLBIN_SIZE) \ | |
1906 | { \ | |
1907 | IDX = smallbin_index(S); \ | |
1908 | mark_binblock(IDX); \ | |
1909 | BK = bin_at(IDX); \ | |
1910 | FD = BK->fd; \ | |
1911 | P->bk = BK; \ | |
1912 | P->fd = FD; \ | |
1913 | FD->bk = BK->fd = P; \ | |
1914 | } \ | |
1915 | else \ | |
1916 | { \ | |
1917 | IDX = bin_index(S); \ | |
1918 | BK = bin_at(IDX); \ | |
1919 | FD = BK->fd; \ | |
1920 | if (FD == BK) mark_binblock(IDX); \ | |
1921 | else \ | |
1922 | { \ | |
1923 | while (FD != BK && S < chunksize(FD)) FD = FD->fd; \ | |
1924 | BK = FD->bk; \ | |
1925 | } \ | |
1926 | P->bk = BK; \ | |
1927 | P->fd = FD; \ | |
1928 | FD->bk = BK->fd = P; \ | |
1929 | } \ | |
1930 | } | |
1931 | ||
1932 | ||
1933 | /* take a chunk off a list */ | |
1934 | ||
1935 | #define unlink(P, BK, FD) \ | |
1936 | { \ | |
1937 | BK = P->bk; \ | |
1938 | FD = P->fd; \ | |
12ee7037 JJ |
1939 | FD->bk = BK; \ |
1940 | BK->fd = FD; \ | |
8a0efa53 CF |
1941 | } \ |
1942 | ||
1943 | /* Place p as the last remainder */ | |
1944 | ||
1945 | #define link_last_remainder(P) \ | |
1946 | { \ | |
1947 | last_remainder->fd = last_remainder->bk = P; \ | |
1948 | P->fd = P->bk = last_remainder; \ | |
1949 | } | |
1950 | ||
1951 | /* Clear the last_remainder bin */ | |
1952 | ||
1953 | #define clear_last_remainder \ | |
1954 | (last_remainder->fd = last_remainder->bk = last_remainder) | |
1955 | ||
1956 | ||
1957 | ||
1958 | \f | |
1959 | ||
1960 | ||
1961 | /* Routines dealing with mmap(). */ | |
1962 | ||
1963 | #if HAVE_MMAP | |
1964 | ||
1965 | #ifdef DEFINE_MALLOC | |
1966 | ||
1967 | #if __STD_C | |
1968 | static mchunkptr mmap_chunk(size_t size) | |
1969 | #else | |
1970 | static mchunkptr mmap_chunk(size) size_t size; | |
1971 | #endif | |
1972 | { | |
1973 | size_t page_mask = malloc_getpagesize - 1; | |
1974 | mchunkptr p; | |
1975 | ||
1976 | #ifndef MAP_ANONYMOUS | |
1977 | static int fd = -1; | |
1978 | #endif | |
1979 | ||
1980 | if(n_mmaps >= n_mmaps_max) return 0; /* too many regions */ | |
1981 | ||
1982 | /* For mmapped chunks, the overhead is one SIZE_SZ unit larger, because | |
1983 | * there is no following chunk whose prev_size field could be used. | |
1984 | */ | |
1985 | size = (size + SIZE_SZ + page_mask) & ~page_mask; | |
1986 | ||
1987 | #ifdef MAP_ANONYMOUS | |
1988 | p = (mchunkptr)mmap(0, size, PROT_READ|PROT_WRITE, | |
1989 | MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); | |
1990 | #else /* !MAP_ANONYMOUS */ | |
1991 | if (fd < 0) | |
1992 | { | |
1993 | fd = open("/dev/zero", O_RDWR); | |
1994 | if(fd < 0) return 0; | |
1995 | } | |
1996 | p = (mchunkptr)mmap(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); | |
1997 | #endif | |
1998 | ||
1999 | if(p == (mchunkptr)-1) return 0; | |
2000 | ||
2001 | n_mmaps++; | |
2002 | if (n_mmaps > max_n_mmaps) max_n_mmaps = n_mmaps; | |
2003 | ||
2004 | /* We demand that eight bytes into a page must be 8-byte aligned. */ | |
2005 | assert(aligned_OK(chunk2mem(p))); | |
2006 | ||
2007 | /* The offset to the start of the mmapped region is stored | |
2008 | * in the prev_size field of the chunk; normally it is zero, | |
2009 | * but that can be changed in memalign(). | |
2010 | */ | |
2011 | p->prev_size = 0; | |
2012 | set_head(p, size|IS_MMAPPED); | |
2013 | ||
2014 | mmapped_mem += size; | |
2015 | if ((unsigned long)mmapped_mem > (unsigned long)max_mmapped_mem) | |
2016 | max_mmapped_mem = mmapped_mem; | |
2017 | if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) | |
2018 | max_total_mem = mmapped_mem + sbrked_mem; | |
2019 | return p; | |
2020 | } | |
2021 | ||
2022 | #endif /* DEFINE_MALLOC */ | |
2023 | ||
2024 | #ifdef SEPARATE_OBJECTS | |
2025 | #define munmap_chunk malloc_munmap_chunk | |
2026 | #endif | |
2027 | ||
2028 | #ifdef DEFINE_FREE | |
2029 | ||
2030 | #if __STD_C | |
2031 | STATIC void munmap_chunk(mchunkptr p) | |
2032 | #else | |
2033 | STATIC void munmap_chunk(p) mchunkptr p; | |
2034 | #endif | |
2035 | { | |
2036 | INTERNAL_SIZE_T size = chunksize(p); | |
2037 | int ret; | |
2038 | ||
2039 | assert (chunk_is_mmapped(p)); | |
2040 | assert(! ((char*)p >= sbrk_base && (char*)p < sbrk_base + sbrked_mem)); | |
2041 | assert((n_mmaps > 0)); | |
2042 | assert(((p->prev_size + size) & (malloc_getpagesize-1)) == 0); | |
2043 | ||
2044 | n_mmaps--; | |
2045 | mmapped_mem -= (size + p->prev_size); | |
2046 | ||
2047 | ret = munmap((char *)p - p->prev_size, size + p->prev_size); | |
2048 | ||
2049 | /* munmap returns non-zero on failure */ | |
2050 | assert(ret == 0); | |
2051 | } | |
2052 | ||
2053 | #else /* ! DEFINE_FREE */ | |
2054 | ||
2055 | #if __STD_C | |
2056 | extern void munmap_chunk(mchunkptr); | |
2057 | #else | |
2058 | extern void munmap_chunk(); | |
2059 | #endif | |
2060 | ||
2061 | #endif /* ! DEFINE_FREE */ | |
2062 | ||
2063 | #if HAVE_MREMAP | |
2064 | ||
2065 | #ifdef DEFINE_REALLOC | |
2066 | ||
2067 | #if __STD_C | |
2068 | static mchunkptr mremap_chunk(mchunkptr p, size_t new_size) | |
2069 | #else | |
2070 | static mchunkptr mremap_chunk(p, new_size) mchunkptr p; size_t new_size; | |
2071 | #endif | |
2072 | { | |
2073 | size_t page_mask = malloc_getpagesize - 1; | |
2074 | INTERNAL_SIZE_T offset = p->prev_size; | |
2075 | INTERNAL_SIZE_T size = chunksize(p); | |
2076 | char *cp; | |
2077 | ||
2078 | assert (chunk_is_mmapped(p)); | |
2079 | assert(! ((char*)p >= sbrk_base && (char*)p < sbrk_base + sbrked_mem)); | |
2080 | assert((n_mmaps > 0)); | |
2081 | assert(((size + offset) & (malloc_getpagesize-1)) == 0); | |
2082 | ||
2083 | /* Note the extra SIZE_SZ overhead as in mmap_chunk(). */ | |
2084 | new_size = (new_size + offset + SIZE_SZ + page_mask) & ~page_mask; | |
2085 | ||
2086 | cp = (char *)mremap((char *)p - offset, size + offset, new_size, 1); | |
2087 | ||
2088 | if (cp == (char *)-1) return 0; | |
2089 | ||
2090 | p = (mchunkptr)(cp + offset); | |
2091 | ||
2092 | assert(aligned_OK(chunk2mem(p))); | |
2093 | ||
2094 | assert((p->prev_size == offset)); | |
2095 | set_head(p, (new_size - offset)|IS_MMAPPED); | |
2096 | ||
2097 | mmapped_mem -= size + offset; | |
2098 | mmapped_mem += new_size; | |
2099 | if ((unsigned long)mmapped_mem > (unsigned long)max_mmapped_mem) | |
2100 | max_mmapped_mem = mmapped_mem; | |
2101 | if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) | |
2102 | max_total_mem = mmapped_mem + sbrked_mem; | |
2103 | return p; | |
2104 | } | |
2105 | ||
2106 | #endif /* DEFINE_REALLOC */ | |
2107 | ||
2108 | #endif /* HAVE_MREMAP */ | |
2109 | ||
2110 | #endif /* HAVE_MMAP */ | |
2111 | ||
2112 | ||
2113 | \f | |
2114 | ||
2115 | #ifdef DEFINE_MALLOC | |
2116 | ||
2117 | /* | |
2118 | Extend the top-most chunk by obtaining memory from system. | |
2119 | Main interface to sbrk (but see also malloc_trim). | |
2120 | */ | |
2121 | ||
2122 | #if __STD_C | |
2123 | static void malloc_extend_top(RARG INTERNAL_SIZE_T nb) | |
2124 | #else | |
2125 | static void malloc_extend_top(RARG nb) RDECL INTERNAL_SIZE_T nb; | |
2126 | #endif | |
2127 | { | |
2128 | char* brk; /* return value from sbrk */ | |
2129 | INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of sbrked space */ | |
2130 | INTERNAL_SIZE_T correction; /* bytes for 2nd sbrk call */ | |
2f3009bd | 2131 | int correction_failed = 0; /* whether we should relax the assertion */ |
8a0efa53 CF |
2132 | char* new_brk; /* return of 2nd sbrk call */ |
2133 | INTERNAL_SIZE_T top_size; /* new size of top chunk */ | |
2134 | ||
2135 | mchunkptr old_top = top; /* Record state of old top */ | |
2136 | INTERNAL_SIZE_T old_top_size = chunksize(old_top); | |
2137 | char* old_end = (char*)(chunk_at_offset(old_top, old_top_size)); | |
2138 | ||
2139 | /* Pad request with top_pad plus minimal overhead */ | |
2140 | ||
2141 | INTERNAL_SIZE_T sbrk_size = nb + top_pad + MINSIZE; | |
2142 | unsigned long pagesz = malloc_getpagesize; | |
2143 | ||
2144 | /* If not the first time through, round to preserve page boundary */ | |
2145 | /* Otherwise, we need to correct to a page size below anyway. */ | |
2146 | /* (We also correct below if an intervening foreign sbrk call.) */ | |
2147 | ||
2148 | if (sbrk_base != (char*)(-1)) | |
2149 | sbrk_size = (sbrk_size + (pagesz - 1)) & ~(pagesz - 1); | |
2150 | ||
2151 | brk = (char*)(MORECORE (sbrk_size)); | |
2152 | ||
2153 | /* Fail if sbrk failed or if a foreign sbrk call killed our space */ | |
2154 | if (brk == (char*)(MORECORE_FAILURE) || | |
2155 | (brk < old_end && old_top != initial_top)) | |
2f3009bd | 2156 | return; |
8a0efa53 CF |
2157 | |
2158 | sbrked_mem += sbrk_size; | |
2159 | ||
2f3009bd AO |
2160 | if (brk == old_end /* can just add bytes to current top, unless |
2161 | previous correction failed */ | |
2162 | && ((POINTER_UINT)old_end & (pagesz - 1)) == 0) | |
8a0efa53 CF |
2163 | { |
2164 | top_size = sbrk_size + old_top_size; | |
2165 | set_head(top, top_size | PREV_INUSE); | |
2166 | } | |
2167 | else | |
2168 | { | |
2169 | if (sbrk_base == (char*)(-1)) /* First time through. Record base */ | |
2170 | sbrk_base = brk; | |
2171 | else /* Someone else called sbrk(). Count those bytes as sbrked_mem. */ | |
2172 | sbrked_mem += brk - (char*)old_end; | |
2173 | ||
2174 | /* Guarantee alignment of first new chunk made from this space */ | |
2175 | front_misalign = (POINTER_UINT)chunk2mem(brk) & MALLOC_ALIGN_MASK; | |
2176 | if (front_misalign > 0) | |
2177 | { | |
2178 | correction = (MALLOC_ALIGNMENT) - front_misalign; | |
2179 | brk += correction; | |
2180 | } | |
2181 | else | |
2182 | correction = 0; | |
2183 | ||
2184 | /* Guarantee the next brk will be at a page boundary */ | |
2185 | correction += pagesz - ((POINTER_UINT)(brk + sbrk_size) & (pagesz - 1)); | |
2186 | ||
2187 | /* Allocate correction */ | |
2188 | new_brk = (char*)(MORECORE (correction)); | |
2f3009bd AO |
2189 | if (new_brk == (char*)(MORECORE_FAILURE)) |
2190 | { | |
2191 | correction = 0; | |
2192 | correction_failed = 1; | |
2193 | new_brk = brk; | |
2194 | } | |
8a0efa53 CF |
2195 | |
2196 | sbrked_mem += correction; | |
2197 | ||
2198 | top = (mchunkptr)brk; | |
2199 | top_size = new_brk - brk + correction; | |
2200 | set_head(top, top_size | PREV_INUSE); | |
2201 | ||
2202 | if (old_top != initial_top) | |
2203 | { | |
2204 | ||
2205 | /* There must have been an intervening foreign sbrk call. */ | |
2206 | /* A double fencepost is necessary to prevent consolidation */ | |
2207 | ||
2208 | /* If not enough space to do this, then user did something very wrong */ | |
2209 | if (old_top_size < MINSIZE) | |
2210 | { | |
2211 | set_head(top, PREV_INUSE); /* will force null return from malloc */ | |
2212 | return; | |
2213 | } | |
2214 | ||
2215 | /* Also keep size a multiple of MALLOC_ALIGNMENT */ | |
2216 | old_top_size = (old_top_size - 3*SIZE_SZ) & ~MALLOC_ALIGN_MASK; | |
2217 | set_head_size(old_top, old_top_size); | |
2218 | chunk_at_offset(old_top, old_top_size )->size = | |
2219 | SIZE_SZ|PREV_INUSE; | |
2220 | chunk_at_offset(old_top, old_top_size + SIZE_SZ)->size = | |
2221 | SIZE_SZ|PREV_INUSE; | |
2222 | /* If possible, release the rest. */ | |
2223 | if (old_top_size >= MINSIZE) | |
2224 | fREe(RCALL chunk2mem(old_top)); | |
2225 | } | |
2226 | } | |
2227 | ||
2228 | if ((unsigned long)sbrked_mem > (unsigned long)max_sbrked_mem) | |
2229 | max_sbrked_mem = sbrked_mem; | |
2230 | #if HAVE_MMAP | |
2231 | if ((unsigned long)(mmapped_mem + sbrked_mem) > (unsigned long)max_total_mem) | |
2232 | max_total_mem = mmapped_mem + sbrked_mem; | |
2233 | #else | |
2234 | if ((unsigned long)(sbrked_mem) > (unsigned long)max_total_mem) | |
2235 | max_total_mem = sbrked_mem; | |
2236 | #endif | |
2237 | ||
2238 | /* We always land on a page boundary */ | |
2f3009bd AO |
2239 | assert(((unsigned long)((char*)top + top_size) & (pagesz - 1)) == 0 |
2240 | || correction_failed); | |
8a0efa53 CF |
2241 | } |
2242 | ||
2243 | #endif /* DEFINE_MALLOC */ | |
2244 | \f | |
2245 | ||
2246 | /* Main public routines */ | |
2247 | ||
2248 | #ifdef DEFINE_MALLOC | |
2249 | ||
2250 | /* | |
2251 | Malloc Algorthim: | |
2252 | ||
2253 | The requested size is first converted into a usable form, `nb'. | |
2254 | This currently means to add 4 bytes overhead plus possibly more to | |
2255 | obtain 8-byte alignment and/or to obtain a size of at least | |
2256 | MINSIZE (currently 16 bytes), the smallest allocatable size. | |
2257 | (All fits are considered `exact' if they are within MINSIZE bytes.) | |
2258 | ||
2259 | From there, the first successful of the following steps is taken: | |
2260 | ||
2261 | 1. The bin corresponding to the request size is scanned, and if | |
2262 | a chunk of exactly the right size is found, it is taken. | |
2263 | ||
2264 | 2. The most recently remaindered chunk is used if it is big | |
2265 | enough. This is a form of (roving) first fit, used only in | |
2266 | the absence of exact fits. Runs of consecutive requests use | |
2267 | the remainder of the chunk used for the previous such request | |
2268 | whenever possible. This limited use of a first-fit style | |
2269 | allocation strategy tends to give contiguous chunks | |
2270 | coextensive lifetimes, which improves locality and can reduce | |
2271 | fragmentation in the long run. | |
2272 | ||
2273 | 3. Other bins are scanned in increasing size order, using a | |
2274 | chunk big enough to fulfill the request, and splitting off | |
2275 | any remainder. This search is strictly by best-fit; i.e., | |
2276 | the smallest (with ties going to approximately the least | |
2277 | recently used) chunk that fits is selected. | |
2278 | ||
2279 | 4. If large enough, the chunk bordering the end of memory | |
2280 | (`top') is split off. (This use of `top' is in accord with | |
2281 | the best-fit search rule. In effect, `top' is treated as | |
2282 | larger (and thus less well fitting) than any other available | |
2283 | chunk since it can be extended to be as large as necessary | |
2284 | (up to system limitations). | |
2285 | ||
2286 | 5. If the request size meets the mmap threshold and the | |
2287 | system supports mmap, and there are few enough currently | |
2288 | allocated mmapped regions, and a call to mmap succeeds, | |
2289 | the request is allocated via direct memory mapping. | |
2290 | ||
2291 | 6. Otherwise, the top of memory is extended by | |
2292 | obtaining more space from the system (normally using sbrk, | |
2293 | but definable to anything else via the MORECORE macro). | |
2294 | Memory is gathered from the system (in system page-sized | |
2295 | units) in a way that allows chunks obtained across different | |
2296 | sbrk calls to be consolidated, but does not require | |
2297 | contiguous memory. Thus, it should be safe to intersperse | |
2298 | mallocs with other sbrk calls. | |
2299 | ||
2300 | ||
2301 | All allocations are made from the the `lowest' part of any found | |
2302 | chunk. (The implementation invariant is that prev_inuse is | |
2303 | always true of any allocated chunk; i.e., that each allocated | |
2304 | chunk borders either a previously allocated and still in-use chunk, | |
2305 | or the base of its memory arena.) | |
2306 | ||
2307 | */ | |
2308 | ||
2309 | #if __STD_C | |
2310 | Void_t* mALLOc(RARG size_t bytes) | |
2311 | #else | |
2312 | Void_t* mALLOc(RARG bytes) RDECL size_t bytes; | |
2313 | #endif | |
2314 | { | |
2315 | #ifdef MALLOC_PROVIDED | |
2316 | ||
2317 | malloc (bytes); | |
2318 | ||
2319 | #else | |
2320 | ||
2321 | mchunkptr victim; /* inspected/selected chunk */ | |
2322 | INTERNAL_SIZE_T victim_size; /* its size */ | |
2323 | int idx; /* index for bin traversal */ | |
2324 | mbinptr bin; /* associated bin */ | |
2325 | mchunkptr remainder; /* remainder from a split */ | |
2326 | long remainder_size; /* its size */ | |
2327 | int remainder_index; /* its bin index */ | |
2328 | unsigned long block; /* block traverser bit */ | |
2329 | int startidx; /* first bin of a traversed block */ | |
2330 | mchunkptr fwd; /* misc temp for linking */ | |
2331 | mchunkptr bck; /* misc temp for linking */ | |
2332 | mbinptr q; /* misc temp */ | |
2333 | ||
2334 | INTERNAL_SIZE_T nb = request2size(bytes); /* padded request size; */ | |
2335 | ||
659e7062 JJ |
2336 | /* Check for overflow and just fail, if so. */ |
2337 | if (nb > INT_MAX) | |
2338 | return 0; | |
2339 | ||
8a0efa53 CF |
2340 | MALLOC_LOCK; |
2341 | ||
2342 | /* Check for exact match in a bin */ | |
2343 | ||
2344 | if (is_small_request(nb)) /* Faster version for small requests */ | |
2345 | { | |
2346 | idx = smallbin_index(nb); | |
2347 | ||
2348 | /* No traversal or size check necessary for small bins. */ | |
2349 | ||
2350 | q = bin_at(idx); | |
2351 | victim = last(q); | |
2352 | ||
2353 | #if MALLOC_ALIGN != 16 | |
2354 | /* Also scan the next one, since it would have a remainder < MINSIZE */ | |
2355 | if (victim == q) | |
2356 | { | |
2357 | q = next_bin(q); | |
2358 | victim = last(q); | |
2359 | } | |
2360 | #endif | |
2361 | if (victim != q) | |
2362 | { | |
2363 | victim_size = chunksize(victim); | |
2364 | unlink(victim, bck, fwd); | |
2365 | set_inuse_bit_at_offset(victim, victim_size); | |
2366 | check_malloced_chunk(victim, nb); | |
2367 | MALLOC_UNLOCK; | |
2368 | return chunk2mem(victim); | |
2369 | } | |
2370 | ||
2371 | idx += 2; /* Set for bin scan below. We've already scanned 2 bins. */ | |
2372 | ||
2373 | } | |
2374 | else | |
2375 | { | |
2376 | idx = bin_index(nb); | |
2377 | bin = bin_at(idx); | |
2378 | ||
2379 | for (victim = last(bin); victim != bin; victim = victim->bk) | |
2380 | { | |
2381 | victim_size = chunksize(victim); | |
2382 | remainder_size = long_sub_size_t(victim_size, nb); | |
2383 | ||
2384 | if (remainder_size >= (long)MINSIZE) /* too big */ | |
2385 | { | |
2386 | --idx; /* adjust to rescan below after checking last remainder */ | |
2387 | break; | |
2388 | } | |
2389 | ||
2390 | else if (remainder_size >= 0) /* exact fit */ | |
2391 | { | |
2392 | unlink(victim, bck, fwd); | |
2393 | set_inuse_bit_at_offset(victim, victim_size); | |
2394 | check_malloced_chunk(victim, nb); | |
2395 | MALLOC_UNLOCK; | |
2396 | return chunk2mem(victim); | |
2397 | } | |
2398 | } | |
2399 | ||
2400 | ++idx; | |
2401 | ||
2402 | } | |
2403 | ||
2404 | /* Try to use the last split-off remainder */ | |
2405 | ||
2406 | if ( (victim = last_remainder->fd) != last_remainder) | |
2407 | { | |
2408 | victim_size = chunksize(victim); | |
2409 | remainder_size = long_sub_size_t(victim_size, nb); | |
2410 | ||
2411 | if (remainder_size >= (long)MINSIZE) /* re-split */ | |
2412 | { | |
2413 | remainder = chunk_at_offset(victim, nb); | |
2414 | set_head(victim, nb | PREV_INUSE); | |
2415 | link_last_remainder(remainder); | |
2416 | set_head(remainder, remainder_size | PREV_INUSE); | |
2417 | set_foot(remainder, remainder_size); | |
2418 | check_malloced_chunk(victim, nb); | |
2419 | MALLOC_UNLOCK; | |
2420 | return chunk2mem(victim); | |
2421 | } | |
2422 | ||
2423 | clear_last_remainder; | |
2424 | ||
2425 | if (remainder_size >= 0) /* exhaust */ | |
2426 | { | |
2427 | set_inuse_bit_at_offset(victim, victim_size); | |
2428 | check_malloced_chunk(victim, nb); | |
2429 | MALLOC_UNLOCK; | |
2430 | return chunk2mem(victim); | |
2431 | } | |
2432 | ||
2433 | /* Else place in bin */ | |
2434 | ||
2435 | frontlink(victim, victim_size, remainder_index, bck, fwd); | |
2436 | } | |
2437 | ||
2438 | /* | |
2439 | If there are any possibly nonempty big-enough blocks, | |
2440 | search for best fitting chunk by scanning bins in blockwidth units. | |
2441 | */ | |
2442 | ||
2443 | if ( (block = idx2binblock(idx)) <= binblocks) | |
2444 | { | |
2445 | ||
2446 | /* Get to the first marked block */ | |
2447 | ||
2448 | if ( (block & binblocks) == 0) | |
2449 | { | |
2450 | /* force to an even block boundary */ | |
2451 | idx = (idx & ~(BINBLOCKWIDTH - 1)) + BINBLOCKWIDTH; | |
2452 | block <<= 1; | |
2453 | while ((block & binblocks) == 0) | |
2454 | { | |
2455 | idx += BINBLOCKWIDTH; | |
2456 | block <<= 1; | |
2457 | } | |
2458 | } | |
2459 | ||
2460 | /* For each possibly nonempty block ... */ | |
2461 | for (;;) | |
2462 | { | |
2463 | startidx = idx; /* (track incomplete blocks) */ | |
2464 | q = bin = bin_at(idx); | |
2465 | ||
2466 | /* For each bin in this block ... */ | |
2467 | do | |
2468 | { | |
2469 | /* Find and use first big enough chunk ... */ | |
2470 | ||
2471 | for (victim = last(bin); victim != bin; victim = victim->bk) | |
2472 | { | |
2473 | victim_size = chunksize(victim); | |
2474 | remainder_size = long_sub_size_t(victim_size, nb); | |
2475 | ||
2476 | if (remainder_size >= (long)MINSIZE) /* split */ | |
2477 | { | |
2478 | remainder = chunk_at_offset(victim, nb); | |
2479 | set_head(victim, nb | PREV_INUSE); | |
2480 | unlink(victim, bck, fwd); | |
2481 | link_last_remainder(remainder); | |
2482 | set_head(remainder, remainder_size | PREV_INUSE); | |
2483 | set_foot(remainder, remainder_size); | |
2484 | check_malloced_chunk(victim, nb); | |
2485 | MALLOC_UNLOCK; | |
2486 | return chunk2mem(victim); | |
2487 | } | |
2488 | ||
2489 | else if (remainder_size >= 0) /* take */ | |
2490 | { | |
2491 | set_inuse_bit_at_offset(victim, victim_size); | |
2492 | unlink(victim, bck, fwd); | |
2493 | check_malloced_chunk(victim, nb); | |
2494 | MALLOC_UNLOCK; | |
2495 | return chunk2mem(victim); | |
2496 | } | |
2497 | ||
2498 | } | |
2499 | ||
2500 | bin = next_bin(bin); | |
2501 | ||
2502 | #if MALLOC_ALIGN == 16 | |
2503 | if (idx < MAX_SMALLBIN) | |
2504 | { | |
2505 | bin = next_bin(bin); | |
2506 | ++idx; | |
2507 | } | |
2508 | #endif | |
2509 | } while ((++idx & (BINBLOCKWIDTH - 1)) != 0); | |
2510 | ||
2511 | /* Clear out the block bit. */ | |
2512 | ||
2513 | do /* Possibly backtrack to try to clear a partial block */ | |
2514 | { | |
2515 | if ((startidx & (BINBLOCKWIDTH - 1)) == 0) | |
2516 | { | |
2517 | binblocks &= ~block; | |
2518 | break; | |
2519 | } | |
2520 | --startidx; | |
2521 | q = prev_bin(q); | |
2522 | } while (first(q) == q); | |
2523 | ||
2524 | /* Get to the next possibly nonempty block */ | |
2525 | ||
2526 | if ( (block <<= 1) <= binblocks && (block != 0) ) | |
2527 | { | |
2528 | while ((block & binblocks) == 0) | |
2529 | { | |
2530 | idx += BINBLOCKWIDTH; | |
2531 | block <<= 1; | |
2532 | } | |
2533 | } | |
2534 | else | |
2535 | break; | |
2536 | } | |
2537 | } | |
2538 | ||
2539 | ||
2540 | /* Try to use top chunk */ | |
2541 | ||
2542 | /* Require that there be a remainder, ensuring top always exists */ | |
2543 | remainder_size = long_sub_size_t(chunksize(top), nb); | |
2544 | if (chunksize(top) < nb || remainder_size < (long)MINSIZE) | |
2545 | { | |
2546 | ||
2547 | #if HAVE_MMAP | |
2548 | /* If big and would otherwise need to extend, try to use mmap instead */ | |
2549 | if ((unsigned long)nb >= (unsigned long)mmap_threshold && | |
2550 | (victim = mmap_chunk(nb)) != 0) | |
2551 | { | |
2552 | MALLOC_UNLOCK; | |
2553 | return chunk2mem(victim); | |
2554 | } | |
2555 | #endif | |
2556 | ||
2557 | /* Try to extend */ | |
2558 | malloc_extend_top(RCALL nb); | |
2559 | remainder_size = long_sub_size_t(chunksize(top), nb); | |
2560 | if (chunksize(top) < nb || remainder_size < (long)MINSIZE) | |
2561 | { | |
2562 | MALLOC_UNLOCK; | |
2563 | return 0; /* propagate failure */ | |
2564 | } | |
2565 | } | |
2566 | ||
2567 | victim = top; | |
2568 | set_head(victim, nb | PREV_INUSE); | |
2569 | top = chunk_at_offset(victim, nb); | |
2570 | set_head(top, remainder_size | PREV_INUSE); | |
2571 | check_malloced_chunk(victim, nb); | |
2572 | MALLOC_UNLOCK; | |
2573 | return chunk2mem(victim); | |
2574 | ||
2575 | #endif /* MALLOC_PROVIDED */ | |
2576 | } | |
2577 | ||
2578 | #endif /* DEFINE_MALLOC */ | |
2579 | \f | |
2580 | #ifdef DEFINE_FREE | |
2581 | ||
2582 | /* | |
2583 | ||
2584 | free() algorithm : | |
2585 | ||
2586 | cases: | |
2587 | ||
2588 | 1. free(0) has no effect. | |
2589 | ||
2590 | 2. If the chunk was allocated via mmap, it is release via munmap(). | |
2591 | ||
2592 | 3. If a returned chunk borders the current high end of memory, | |
2593 | it is consolidated into the top, and if the total unused | |
2594 | topmost memory exceeds the trim threshold, malloc_trim is | |
2595 | called. | |
2596 | ||
2597 | 4. Other chunks are consolidated as they arrive, and | |
2598 | placed in corresponding bins. (This includes the case of | |
2599 | consolidating with the current `last_remainder'). | |
2600 | ||
2601 | */ | |
2602 | ||
2603 | ||
2604 | #if __STD_C | |
2605 | void fREe(RARG Void_t* mem) | |
2606 | #else | |
2607 | void fREe(RARG mem) RDECL Void_t* mem; | |
2608 | #endif | |
2609 | { | |
2610 | #ifdef MALLOC_PROVIDED | |
2611 | ||
2612 | free (mem); | |
2613 | ||
2614 | #else | |
2615 | ||
2616 | mchunkptr p; /* chunk corresponding to mem */ | |
2617 | INTERNAL_SIZE_T hd; /* its head field */ | |
2618 | INTERNAL_SIZE_T sz; /* its size */ | |
2619 | int idx; /* its bin index */ | |
2620 | mchunkptr next; /* next contiguous chunk */ | |
2621 | INTERNAL_SIZE_T nextsz; /* its size */ | |
2622 | INTERNAL_SIZE_T prevsz; /* size of previous contiguous chunk */ | |
2623 | mchunkptr bck; /* misc temp for linking */ | |
2624 | mchunkptr fwd; /* misc temp for linking */ | |
2625 | int islr; /* track whether merging with last_remainder */ | |
2626 | ||
2627 | if (mem == 0) /* free(0) has no effect */ | |
2628 | return; | |
2629 | ||
2630 | MALLOC_LOCK; | |
2631 | ||
2632 | p = mem2chunk(mem); | |
2633 | hd = p->size; | |
2634 | ||
2635 | #if HAVE_MMAP | |
2636 | if (hd & IS_MMAPPED) /* release mmapped memory. */ | |
2637 | { | |
2638 | munmap_chunk(p); | |
2639 | MALLOC_UNLOCK; | |
2640 | return; | |
2641 | } | |
2642 | #endif | |
2643 | ||
2644 | check_inuse_chunk(p); | |
2645 | ||
2646 | sz = hd & ~PREV_INUSE; | |
2647 | next = chunk_at_offset(p, sz); | |
2648 | nextsz = chunksize(next); | |
2649 | ||
2650 | if (next == top) /* merge with top */ | |
2651 | { | |
2652 | sz += nextsz; | |
2653 | ||
2654 | if (!(hd & PREV_INUSE)) /* consolidate backward */ | |
2655 | { | |
2656 | prevsz = p->prev_size; | |
2657 | p = chunk_at_offset(p, -prevsz); | |
2658 | sz += prevsz; | |
2659 | unlink(p, bck, fwd); | |
2660 | } | |
2661 | ||
2662 | set_head(p, sz | PREV_INUSE); | |
2663 | top = p; | |
2664 | if ((unsigned long)(sz) >= (unsigned long)trim_threshold) | |
2665 | malloc_trim(RCALL top_pad); | |
2666 | MALLOC_UNLOCK; | |
2667 | return; | |
2668 | } | |
2669 | ||
2670 | set_head(next, nextsz); /* clear inuse bit */ | |
2671 | ||
2672 | islr = 0; | |
2673 | ||
2674 | if (!(hd & PREV_INUSE)) /* consolidate backward */ | |
2675 | { | |
2676 | prevsz = p->prev_size; | |
2677 | p = chunk_at_offset(p, -prevsz); | |
2678 | sz += prevsz; | |
2679 | ||
2680 | if (p->fd == last_remainder) /* keep as last_remainder */ | |
2681 | islr = 1; | |
2682 | else | |
2683 | unlink(p, bck, fwd); | |
2684 | } | |
2685 | ||
2686 | if (!(inuse_bit_at_offset(next, nextsz))) /* consolidate forward */ | |
2687 | { | |
2688 | sz += nextsz; | |
2689 | ||
2690 | if (!islr && next->fd == last_remainder) /* re-insert last_remainder */ | |
2691 | { | |
2692 | islr = 1; | |
2693 | link_last_remainder(p); | |
2694 | } | |
2695 | else | |
2696 | unlink(next, bck, fwd); | |
2697 | } | |
2698 | ||
2699 | ||
2700 | set_head(p, sz | PREV_INUSE); | |
2701 | set_foot(p, sz); | |
2702 | if (!islr) | |
2703 | frontlink(p, sz, idx, bck, fwd); | |
2704 | ||
2705 | MALLOC_UNLOCK; | |
2706 | ||
2707 | #endif /* MALLOC_PROVIDED */ | |
2708 | } | |
2709 | ||
2710 | #endif /* DEFINE_FREE */ | |
2711 | \f | |
2712 | #ifdef DEFINE_REALLOC | |
2713 | ||
2714 | /* | |
2715 | ||
2716 | Realloc algorithm: | |
2717 | ||
2718 | Chunks that were obtained via mmap cannot be extended or shrunk | |
2719 | unless HAVE_MREMAP is defined, in which case mremap is used. | |
2720 | Otherwise, if their reallocation is for additional space, they are | |
2721 | copied. If for less, they are just left alone. | |
2722 | ||
2723 | Otherwise, if the reallocation is for additional space, and the | |
2724 | chunk can be extended, it is, else a malloc-copy-free sequence is | |
2725 | taken. There are several different ways that a chunk could be | |
2726 | extended. All are tried: | |
2727 | ||
2728 | * Extending forward into following adjacent free chunk. | |
2729 | * Shifting backwards, joining preceding adjacent space | |
2730 | * Both shifting backwards and extending forward. | |
2731 | * Extending into newly sbrked space | |
2732 | ||
2733 | Unless the #define REALLOC_ZERO_BYTES_FREES is set, realloc with a | |
2734 | size argument of zero (re)allocates a minimum-sized chunk. | |
2735 | ||
2736 | If the reallocation is for less space, and the new request is for | |
2737 | a `small' (<512 bytes) size, then the newly unused space is lopped | |
2738 | off and freed. | |
2739 | ||
2740 | The old unix realloc convention of allowing the last-free'd chunk | |
2741 | to be used as an argument to realloc is no longer supported. | |
2742 | I don't know of any programs still relying on this feature, | |
2743 | and allowing it would also allow too many other incorrect | |
2744 | usages of realloc to be sensible. | |
2745 | ||
2746 | ||
2747 | */ | |
2748 | ||
2749 | ||
2750 | #if __STD_C | |
2751 | Void_t* rEALLOc(RARG Void_t* oldmem, size_t bytes) | |
2752 | #else | |
2753 | Void_t* rEALLOc(RARG oldmem, bytes) RDECL Void_t* oldmem; size_t bytes; | |
2754 | #endif | |
2755 | { | |
2756 | #ifdef MALLOC_PROVIDED | |
2757 | ||
2758 | realloc (oldmem, bytes); | |
2759 | ||
2760 | #else | |
2761 | ||
2762 | INTERNAL_SIZE_T nb; /* padded request size */ | |
2763 | ||
2764 | mchunkptr oldp; /* chunk corresponding to oldmem */ | |
2765 | INTERNAL_SIZE_T oldsize; /* its size */ | |
2766 | ||
2767 | mchunkptr newp; /* chunk to return */ | |
2768 | INTERNAL_SIZE_T newsize; /* its size */ | |
2769 | Void_t* newmem; /* corresponding user mem */ | |
2770 | ||
2771 | mchunkptr next; /* next contiguous chunk after oldp */ | |
2772 | INTERNAL_SIZE_T nextsize; /* its size */ | |
2773 | ||
2774 | mchunkptr prev; /* previous contiguous chunk before oldp */ | |
2775 | INTERNAL_SIZE_T prevsize; /* its size */ | |
2776 | ||
2777 | mchunkptr remainder; /* holds split off extra space from newp */ | |
2778 | INTERNAL_SIZE_T remainder_size; /* its size */ | |
2779 | ||
2780 | mchunkptr bck; /* misc temp for linking */ | |
2781 | mchunkptr fwd; /* misc temp for linking */ | |
2782 | ||
2783 | #ifdef REALLOC_ZERO_BYTES_FREES | |
2784 | if (bytes == 0) { fREe(RCALL oldmem); return 0; } | |
2785 | #endif | |
2786 | ||
2787 | ||
2788 | /* realloc of null is supposed to be same as malloc */ | |
2789 | if (oldmem == 0) return mALLOc(RCALL bytes); | |
2790 | ||
2791 | MALLOC_LOCK; | |
2792 | ||
2793 | newp = oldp = mem2chunk(oldmem); | |
2794 | newsize = oldsize = chunksize(oldp); | |
2795 | ||
2796 | ||
2797 | nb = request2size(bytes); | |
2798 | ||
659e7062 JJ |
2799 | /* Check for overflow and just fail, if so. */ |
2800 | if (nb > INT_MAX) | |
2801 | return 0; | |
2802 | ||
8a0efa53 CF |
2803 | #if HAVE_MMAP |
2804 | if (chunk_is_mmapped(oldp)) | |
2805 | { | |
2806 | #if HAVE_MREMAP | |
2807 | newp = mremap_chunk(oldp, nb); | |
2808 | if(newp) | |
2809 | { | |
2810 | MALLOC_UNLOCK; | |
2811 | return chunk2mem(newp); | |
2812 | } | |
2813 | #endif | |
2814 | /* Note the extra SIZE_SZ overhead. */ | |
2815 | if(oldsize - SIZE_SZ >= nb) | |
2816 | { | |
2817 | MALLOC_UNLOCK; | |
2818 | return oldmem; /* do nothing */ | |
2819 | } | |
2820 | /* Must alloc, copy, free. */ | |
2821 | newmem = mALLOc(RCALL bytes); | |
2822 | if (newmem == 0) | |
2823 | { | |
2824 | MALLOC_UNLOCK; | |
2825 | return 0; /* propagate failure */ | |
2826 | } | |
2827 | MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ); | |
2828 | munmap_chunk(oldp); | |
2829 | MALLOC_UNLOCK; | |
2830 | return newmem; | |
2831 | } | |
2832 | #endif | |
2833 | ||
2834 | check_inuse_chunk(oldp); | |
2835 | ||
2836 | if ((long)(oldsize) < (long)(nb)) | |
2837 | { | |
2838 | ||
2839 | /* Try expanding forward */ | |
2840 | ||
2841 | next = chunk_at_offset(oldp, oldsize); | |
2842 | if (next == top || !inuse(next)) | |
2843 | { | |
2844 | nextsize = chunksize(next); | |
2845 | ||
2846 | /* Forward into top only if a remainder */ | |
2847 | if (next == top) | |
2848 | { | |
2849 | if ((long)(nextsize + newsize) >= (long)(nb + MINSIZE)) | |
2850 | { | |
2851 | newsize += nextsize; | |
2852 | top = chunk_at_offset(oldp, nb); | |
2853 | set_head(top, (newsize - nb) | PREV_INUSE); | |
2854 | set_head_size(oldp, nb); | |
2855 | MALLOC_UNLOCK; | |
2856 | return chunk2mem(oldp); | |
2857 | } | |
2858 | } | |
2859 | ||
2860 | /* Forward into next chunk */ | |
2861 | else if (((long)(nextsize + newsize) >= (long)(nb))) | |
2862 | { | |
2863 | unlink(next, bck, fwd); | |
2864 | newsize += nextsize; | |
2865 | goto split; | |
2866 | } | |
2867 | } | |
2868 | else | |
2869 | { | |
2870 | next = 0; | |
2871 | nextsize = 0; | |
2872 | } | |
2873 | ||
2874 | /* Try shifting backwards. */ | |
2875 | ||
2876 | if (!prev_inuse(oldp)) | |
2877 | { | |
2878 | prev = prev_chunk(oldp); | |
2879 | prevsize = chunksize(prev); | |
2880 | ||
2881 | /* try forward + backward first to save a later consolidation */ | |
2882 | ||
2883 | if (next != 0) | |
2884 | { | |
2885 | /* into top */ | |
2886 | if (next == top) | |
2887 | { | |
2888 | if ((long)(nextsize + prevsize + newsize) >= (long)(nb + MINSIZE)) | |
2889 | { | |
2890 | unlink(prev, bck, fwd); | |
2891 | newp = prev; | |
2892 | newsize += prevsize + nextsize; | |
2893 | newmem = chunk2mem(newp); | |
2894 | MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); | |
2895 | top = chunk_at_offset(newp, nb); | |
2896 | set_head(top, (newsize - nb) | PREV_INUSE); | |
2897 | set_head_size(newp, nb); | |
2898 | MALLOC_UNLOCK; | |
2899 | return newmem; | |
2900 | } | |
2901 | } | |
2902 | ||
2903 | /* into next chunk */ | |
2904 | else if (((long)(nextsize + prevsize + newsize) >= (long)(nb))) | |
2905 | { | |
2906 | unlink(next, bck, fwd); | |
2907 | unlink(prev, bck, fwd); | |
2908 | newp = prev; | |
2909 | newsize += nextsize + prevsize; | |
2910 | newmem = chunk2mem(newp); | |
2911 | MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); | |
2912 | goto split; | |
2913 | } | |
2914 | } | |
2915 | ||
2916 | /* backward only */ | |
2917 | if (prev != 0 && (long)(prevsize + newsize) >= (long)nb) | |
2918 | { | |
2919 | unlink(prev, bck, fwd); | |
2920 | newp = prev; | |
2921 | newsize += prevsize; | |
2922 | newmem = chunk2mem(newp); | |
2923 | MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); | |
2924 | goto split; | |
2925 | } | |
2926 | } | |
2927 | ||
2928 | /* Must allocate */ | |
2929 | ||
2930 | newmem = mALLOc (RCALL bytes); | |
2931 | ||
2932 | if (newmem == 0) /* propagate failure */ | |
2933 | { | |
2934 | MALLOC_UNLOCK; | |
2935 | return 0; | |
2936 | } | |
2937 | ||
2938 | /* Avoid copy if newp is next chunk after oldp. */ | |
2939 | /* (This can only happen when new chunk is sbrk'ed.) */ | |
2940 | ||
2941 | if ( (newp = mem2chunk(newmem)) == next_chunk(oldp)) | |
2942 | { | |
2943 | newsize += chunksize(newp); | |
2944 | newp = oldp; | |
2945 | goto split; | |
2946 | } | |
2947 | ||
2948 | /* Otherwise copy, free, and exit */ | |
2949 | MALLOC_COPY(newmem, oldmem, oldsize - SIZE_SZ); | |
2950 | fREe(RCALL oldmem); | |
2951 | MALLOC_UNLOCK; | |
2952 | return newmem; | |
2953 | } | |
2954 | ||
2955 | ||
2956 | split: /* split off extra room in old or expanded chunk */ | |
2957 | ||
2958 | remainder_size = long_sub_size_t(newsize, nb); | |
2959 | ||
2960 | if (remainder_size >= (long)MINSIZE) /* split off remainder */ | |
2961 | { | |
2962 | remainder = chunk_at_offset(newp, nb); | |
2963 | set_head_size(newp, nb); | |
2964 | set_head(remainder, remainder_size | PREV_INUSE); | |
2965 | set_inuse_bit_at_offset(remainder, remainder_size); | |
2966 | fREe(RCALL chunk2mem(remainder)); /* let free() deal with it */ | |
2967 | } | |
2968 | else | |
2969 | { | |
2970 | set_head_size(newp, newsize); | |
2971 | set_inuse_bit_at_offset(newp, newsize); | |
2972 | } | |
2973 | ||
2974 | check_inuse_chunk(newp); | |
2975 | MALLOC_UNLOCK; | |
2976 | return chunk2mem(newp); | |
2977 | ||
2978 | #endif /* MALLOC_PROVIDED */ | |
2979 | } | |
2980 | ||
2981 | #endif /* DEFINE_REALLOC */ | |
2982 | \f | |
2983 | #ifdef DEFINE_MEMALIGN | |
2984 | ||
2985 | /* | |
2986 | ||
2987 | memalign algorithm: | |
2988 | ||
2989 | memalign requests more than enough space from malloc, finds a spot | |
2990 | within that chunk that meets the alignment request, and then | |
2991 | possibly frees the leading and trailing space. | |
2992 | ||
2993 | The alignment argument must be a power of two. This property is not | |
2994 | checked by memalign, so misuse may result in random runtime errors. | |
2995 | ||
2996 | 8-byte alignment is guaranteed by normal malloc calls, so don't | |
2997 | bother calling memalign with an argument of 8 or less. | |
2998 | ||
2999 | Overreliance on memalign is a sure way to fragment space. | |
3000 | ||
3001 | */ | |
3002 | ||
3003 | ||
3004 | #if __STD_C | |
3005 | Void_t* mEMALIGn(RARG size_t alignment, size_t bytes) | |
3006 | #else | |
3007 | Void_t* mEMALIGn(RARG alignment, bytes) RDECL size_t alignment; size_t bytes; | |
3008 | #endif | |
3009 | { | |
3010 | INTERNAL_SIZE_T nb; /* padded request size */ | |
3011 | char* m; /* memory returned by malloc call */ | |
3012 | mchunkptr p; /* corresponding chunk */ | |
3013 | char* brk; /* alignment point within p */ | |
3014 | mchunkptr newp; /* chunk to return */ | |
3015 | INTERNAL_SIZE_T newsize; /* its size */ | |
3016 | INTERNAL_SIZE_T leadsize; /* leading space befor alignment point */ | |
3017 | mchunkptr remainder; /* spare room at end to split off */ | |
3018 | long remainder_size; /* its size */ | |
3019 | ||
3020 | /* If need less alignment than we give anyway, just relay to malloc */ | |
3021 | ||
3022 | if (alignment <= MALLOC_ALIGNMENT) return mALLOc(RCALL bytes); | |
3023 | ||
3024 | /* Otherwise, ensure that it is at least a minimum chunk size */ | |
3025 | ||
3026 | if (alignment < MINSIZE) alignment = MINSIZE; | |
3027 | ||
3028 | /* Call malloc with worst case padding to hit alignment. */ | |
3029 | ||
3030 | nb = request2size(bytes); | |
3031 | m = (char*)(mALLOc(RCALL nb + alignment + MINSIZE)); | |
3032 | ||
3033 | if (m == 0) return 0; /* propagate failure */ | |
3034 | ||
3035 | MALLOC_LOCK; | |
3036 | ||
3037 | p = mem2chunk(m); | |
3038 | ||
3039 | if ((((unsigned long)(m)) % alignment) == 0) /* aligned */ | |
3040 | { | |
3041 | #if HAVE_MMAP | |
3042 | if(chunk_is_mmapped(p)) | |
3043 | { | |
3044 | MALLOC_UNLOCK; | |
3045 | return chunk2mem(p); /* nothing more to do */ | |
3046 | } | |
3047 | #endif | |
3048 | } | |
3049 | else /* misaligned */ | |
3050 | { | |
3051 | /* | |
3052 | Find an aligned spot inside chunk. | |
3053 | Since we need to give back leading space in a chunk of at | |
3054 | least MINSIZE, if the first calculation places us at | |
3055 | a spot with less than MINSIZE leader, we can move to the | |
3056 | next aligned spot -- we've allocated enough total room so that | |
3057 | this is always possible. | |
3058 | */ | |
3059 | ||
3060 | brk = (char*)mem2chunk(((unsigned long)(m + alignment - 1)) & -alignment); | |
3061 | if ((long)(brk - (char*)(p)) < (long)MINSIZE) brk = brk + alignment; | |
3062 | ||
3063 | newp = (mchunkptr)brk; | |
3064 | leadsize = brk - (char*)(p); | |
3065 | newsize = chunksize(p) - leadsize; | |
3066 | ||
3067 | #if HAVE_MMAP | |
3068 | if(chunk_is_mmapped(p)) | |
3069 | { | |
3070 | newp->prev_size = p->prev_size + leadsize; | |
3071 | set_head(newp, newsize|IS_MMAPPED); | |
3072 | MALLOC_UNLOCK; | |
3073 | return chunk2mem(newp); | |
3074 | } | |
3075 | #endif | |
3076 | ||
3077 | /* give back leader, use the rest */ | |
3078 | ||
3079 | set_head(newp, newsize | PREV_INUSE); | |
3080 | set_inuse_bit_at_offset(newp, newsize); | |
3081 | set_head_size(p, leadsize); | |
3082 | fREe(RCALL chunk2mem(p)); | |
3083 | p = newp; | |
3084 | ||
3085 | assert (newsize >= nb && (((unsigned long)(chunk2mem(p))) % alignment) == 0); | |
3086 | } | |
3087 | ||
3088 | /* Also give back spare room at the end */ | |
3089 | ||
3090 | remainder_size = long_sub_size_t(chunksize(p), nb); | |
3091 | ||
3092 | if (remainder_size >= (long)MINSIZE) | |
3093 | { | |
3094 | remainder = chunk_at_offset(p, nb); | |
3095 | set_head(remainder, remainder_size | PREV_INUSE); | |
3096 | set_head_size(p, nb); | |
3097 | fREe(RCALL chunk2mem(remainder)); | |
3098 | } | |
3099 | ||
3100 | check_inuse_chunk(p); | |
3101 | MALLOC_UNLOCK; | |
3102 | return chunk2mem(p); | |
3103 | ||
3104 | } | |
3105 | ||
3106 | #endif /* DEFINE_MEMALIGN */ | |
3107 | \f | |
3108 | #ifdef DEFINE_VALLOC | |
3109 | ||
3110 | /* | |
3111 | valloc just invokes memalign with alignment argument equal | |
3112 | to the page size of the system (or as near to this as can | |
3113 | be figured out from all the includes/defines above.) | |
3114 | */ | |
3115 | ||
3116 | #if __STD_C | |
3117 | Void_t* vALLOc(RARG size_t bytes) | |
3118 | #else | |
3119 | Void_t* vALLOc(RARG bytes) RDECL size_t bytes; | |
3120 | #endif | |
3121 | { | |
3122 | return mEMALIGn (RCALL malloc_getpagesize, bytes); | |
3123 | } | |
3124 | ||
3125 | #endif /* DEFINE_VALLOC */ | |
3126 | ||
3127 | #ifdef DEFINE_PVALLOC | |
3128 | ||
3129 | /* | |
3130 | pvalloc just invokes valloc for the nearest pagesize | |
3131 | that will accommodate request | |
3132 | */ | |
3133 | ||
3134 | ||
3135 | #if __STD_C | |
3136 | Void_t* pvALLOc(RARG size_t bytes) | |
3137 | #else | |
3138 | Void_t* pvALLOc(RARG bytes) RDECL size_t bytes; | |
3139 | #endif | |
3140 | { | |
3141 | size_t pagesize = malloc_getpagesize; | |
3142 | return mEMALIGn (RCALL pagesize, (bytes + pagesize - 1) & ~(pagesize - 1)); | |
3143 | } | |
3144 | ||
3145 | #endif /* DEFINE_PVALLOC */ | |
3146 | ||
3147 | #ifdef DEFINE_CALLOC | |
3148 | ||
3149 | /* | |
3150 | ||
3151 | calloc calls malloc, then zeroes out the allocated chunk. | |
3152 | ||
3153 | */ | |
3154 | ||
3155 | #if __STD_C | |
3156 | Void_t* cALLOc(RARG size_t n, size_t elem_size) | |
3157 | #else | |
3158 | Void_t* cALLOc(RARG n, elem_size) RDECL size_t n; size_t elem_size; | |
3159 | #endif | |
3160 | { | |
3161 | mchunkptr p; | |
3162 | INTERNAL_SIZE_T csz; | |
3163 | ||
3164 | INTERNAL_SIZE_T sz = n * elem_size; | |
3165 | ||
3166 | #if MORECORE_CLEARS | |
3167 | mchunkptr oldtop; | |
3168 | INTERNAL_SIZE_T oldtopsize; | |
3169 | #endif | |
3170 | Void_t* mem; | |
3171 | ||
3172 | /* check if expand_top called, in which case don't need to clear */ | |
3173 | #if MORECORE_CLEARS | |
3174 | MALLOC_LOCK; | |
3175 | oldtop = top; | |
3176 | oldtopsize = chunksize(top); | |
3177 | #endif | |
3178 | ||
3179 | mem = mALLOc (RCALL sz); | |
3180 | ||
3181 | if (mem == 0) | |
3182 | { | |
3183 | #if MORECORE_CLEARS | |
3184 | MALLOC_UNLOCK; | |
3185 | #endif | |
3186 | return 0; | |
3187 | } | |
3188 | else | |
3189 | { | |
3190 | p = mem2chunk(mem); | |
3191 | ||
3192 | /* Two optional cases in which clearing not necessary */ | |
3193 | ||
3194 | ||
3195 | #if HAVE_MMAP | |
3196 | if (chunk_is_mmapped(p)) | |
3197 | { | |
3198 | #if MORECORE_CLEARS | |
3199 | MALLOC_UNLOCK; | |
3200 | #endif | |
3201 | return mem; | |
3202 | } | |
3203 | #endif | |
3204 | ||
3205 | csz = chunksize(p); | |
3206 | ||
3207 | #if MORECORE_CLEARS | |
3208 | if (p == oldtop && csz > oldtopsize) | |
3209 | { | |
3210 | /* clear only the bytes from non-freshly-sbrked memory */ | |
3211 | csz = oldtopsize; | |
3212 | } | |
3213 | MALLOC_UNLOCK; | |
3214 | #endif | |
3215 | ||
3216 | MALLOC_ZERO(mem, csz - SIZE_SZ); | |
3217 | return mem; | |
3218 | } | |
3219 | } | |
3220 | ||
3221 | #endif /* DEFINE_CALLOC */ | |
3222 | ||
a385ae75 | 3223 | #if defined(DEFINE_CFREE) && !defined(__CYGWIN__) |
8a0efa53 CF |
3224 | |
3225 | /* | |
3226 | ||
3227 | cfree just calls free. It is needed/defined on some systems | |
3228 | that pair it with calloc, presumably for odd historical reasons. | |
3229 | ||
3230 | */ | |
3231 | ||
3232 | #if !defined(INTERNAL_LINUX_C_LIB) || !defined(__ELF__) | |
3233 | #if !defined(INTERNAL_NEWLIB) || !defined(_REENT_ONLY) | |
3234 | #if __STD_C | |
3235 | void cfree(Void_t *mem) | |
3236 | #else | |
3237 | void cfree(mem) Void_t *mem; | |
3238 | #endif | |
3239 | { | |
3240 | #ifdef INTERNAL_NEWLIB | |
3241 | fREe(_REENT, mem); | |
3242 | #else | |
3243 | fREe(mem); | |
3244 | #endif | |
3245 | } | |
3246 | #endif | |
3247 | #endif | |
3248 | ||
3249 | #endif /* DEFINE_CFREE */ | |
3250 | \f | |
3251 | #ifdef DEFINE_FREE | |
3252 | ||
3253 | /* | |
3254 | ||
3255 | Malloc_trim gives memory back to the system (via negative | |
3256 | arguments to sbrk) if there is unused memory at the `high' end of | |
3257 | the malloc pool. You can call this after freeing large blocks of | |
3258 | memory to potentially reduce the system-level memory requirements | |
3259 | of a program. However, it cannot guarantee to reduce memory. Under | |
3260 | some allocation patterns, some large free blocks of memory will be | |
3261 | locked between two used chunks, so they cannot be given back to | |
3262 | the system. | |
3263 | ||
3264 | The `pad' argument to malloc_trim represents the amount of free | |
3265 | trailing space to leave untrimmed. If this argument is zero, | |
3266 | only the minimum amount of memory to maintain internal data | |
3267 | structures will be left (one page or less). Non-zero arguments | |
3268 | can be supplied to maintain enough trailing space to service | |
3269 | future expected allocations without having to re-obtain memory | |
3270 | from the system. | |
3271 | ||
3272 | Malloc_trim returns 1 if it actually released any memory, else 0. | |
3273 | ||
3274 | */ | |
3275 | ||
3276 | #if __STD_C | |
3277 | int malloc_trim(RARG size_t pad) | |
3278 | #else | |
3279 | int malloc_trim(RARG pad) RDECL size_t pad; | |
3280 | #endif | |
3281 | { | |
3282 | long top_size; /* Amount of top-most memory */ | |
3283 | long extra; /* Amount to release */ | |
3284 | char* current_brk; /* address returned by pre-check sbrk call */ | |
3285 | char* new_brk; /* address returned by negative sbrk call */ | |
3286 | ||
3287 | unsigned long pagesz = malloc_getpagesize; | |
3288 | ||
3289 | MALLOC_LOCK; | |
3290 | ||
3291 | top_size = chunksize(top); | |
3292 | extra = ((top_size - pad - MINSIZE + (pagesz-1)) / pagesz - 1) * pagesz; | |
3293 | ||
3294 | if (extra < (long)pagesz) /* Not enough memory to release */ | |
3295 | { | |
3296 | MALLOC_UNLOCK; | |
3297 | return 0; | |
3298 | } | |
3299 | ||
3300 | else | |
3301 | { | |
3302 | /* Test to make sure no one else called sbrk */ | |
3303 | current_brk = (char*)(MORECORE (0)); | |
3304 | if (current_brk != (char*)(top) + top_size) | |
3305 | { | |
3306 | MALLOC_UNLOCK; | |
3307 | return 0; /* Apparently we don't own memory; must fail */ | |
3308 | } | |
3309 | ||
3310 | else | |
3311 | { | |
3312 | new_brk = (char*)(MORECORE (-extra)); | |
3313 | ||
3314 | if (new_brk == (char*)(MORECORE_FAILURE)) /* sbrk failed? */ | |
3315 | { | |
3316 | /* Try to figure out what we have */ | |
3317 | current_brk = (char*)(MORECORE (0)); | |
3318 | top_size = current_brk - (char*)top; | |
3319 | if (top_size >= (long)MINSIZE) /* if not, we are very very dead! */ | |
3320 | { | |
3321 | sbrked_mem = current_brk - sbrk_base; | |
3322 | set_head(top, top_size | PREV_INUSE); | |
3323 | } | |
3324 | check_chunk(top); | |
3325 | MALLOC_UNLOCK; | |
3326 | return 0; | |
3327 | } | |
3328 | ||
3329 | else | |
3330 | { | |
3331 | /* Success. Adjust top accordingly. */ | |
3332 | set_head(top, (top_size - extra) | PREV_INUSE); | |
3333 | sbrked_mem -= extra; | |
3334 | check_chunk(top); | |
3335 | MALLOC_UNLOCK; | |
3336 | return 1; | |
3337 | } | |
3338 | } | |
3339 | } | |
3340 | } | |
3341 | ||
3342 | #endif /* DEFINE_FREE */ | |
3343 | \f | |
3344 | #ifdef DEFINE_MALLOC_USABLE_SIZE | |
3345 | ||
3346 | /* | |
3347 | malloc_usable_size: | |
3348 | ||
3349 | This routine tells you how many bytes you can actually use in an | |
3350 | allocated chunk, which may be more than you requested (although | |
3351 | often not). You can use this many bytes without worrying about | |
3352 | overwriting other allocated objects. Not a particularly great | |
3353 | programming practice, but still sometimes useful. | |
3354 | ||
3355 | */ | |
3356 | ||
3357 | #if __STD_C | |
3358 | size_t malloc_usable_size(RARG Void_t* mem) | |
3359 | #else | |
3360 | size_t malloc_usable_size(RARG mem) RDECL Void_t* mem; | |
3361 | #endif | |
3362 | { | |
3363 | mchunkptr p; | |
3364 | if (mem == 0) | |
3365 | return 0; | |
3366 | else | |
3367 | { | |
3368 | p = mem2chunk(mem); | |
3369 | if(!chunk_is_mmapped(p)) | |
3370 | { | |
3371 | if (!inuse(p)) return 0; | |
3372 | #if DEBUG | |
3373 | MALLOC_LOCK; | |
3374 | check_inuse_chunk(p); | |
3375 | MALLOC_UNLOCK; | |
3376 | #endif | |
3377 | return chunksize(p) - SIZE_SZ; | |
3378 | } | |
3379 | return chunksize(p) - 2*SIZE_SZ; | |
3380 | } | |
3381 | } | |
3382 | ||
3383 | #endif /* DEFINE_MALLOC_USABLE_SIZE */ | |
3384 | \f | |
3385 | #ifdef DEFINE_MALLINFO | |
3386 | ||
3387 | /* Utility to update current_mallinfo for malloc_stats and mallinfo() */ | |
3388 | ||
3389 | STATIC void malloc_update_mallinfo() | |
3390 | { | |
3391 | int i; | |
3392 | mbinptr b; | |
3393 | mchunkptr p; | |
3394 | #if DEBUG | |
3395 | mchunkptr q; | |
3396 | #endif | |
3397 | ||
3398 | INTERNAL_SIZE_T avail = chunksize(top); | |
3399 | int navail = ((long)(avail) >= (long)MINSIZE)? 1 : 0; | |
3400 | ||
3401 | for (i = 1; i < NAV; ++i) | |
3402 | { | |
3403 | b = bin_at(i); | |
3404 | for (p = last(b); p != b; p = p->bk) | |
3405 | { | |
3406 | #if DEBUG | |
3407 | check_free_chunk(p); | |
3408 | for (q = next_chunk(p); | |
3409 | q < top && inuse(q) && (long)(chunksize(q)) >= (long)MINSIZE; | |
3410 | q = next_chunk(q)) | |
3411 | check_inuse_chunk(q); | |
3412 | #endif | |
3413 | avail += chunksize(p); | |
3414 | navail++; | |
3415 | } | |
3416 | } | |
3417 | ||
3418 | current_mallinfo.ordblks = navail; | |
3419 | current_mallinfo.uordblks = sbrked_mem - avail; | |
3420 | current_mallinfo.fordblks = avail; | |
3421 | #if HAVE_MMAP | |
3422 | current_mallinfo.hblks = n_mmaps; | |
3423 | current_mallinfo.hblkhd = mmapped_mem; | |
3424 | #endif | |
3425 | current_mallinfo.keepcost = chunksize(top); | |
3426 | ||
3427 | } | |
3428 | ||
3429 | #else /* ! DEFINE_MALLINFO */ | |
3430 | ||
3431 | #if __STD_C | |
3432 | extern void malloc_update_mallinfo(void); | |
3433 | #else | |
3434 | extern void malloc_update_mallinfo(); | |
3435 | #endif | |
3436 | ||
3437 | #endif /* ! DEFINE_MALLINFO */ | |
3438 | \f | |
3439 | #ifdef DEFINE_MALLOC_STATS | |
3440 | ||
3441 | /* | |
3442 | ||
3443 | malloc_stats: | |
3444 | ||
3445 | Prints on stderr the amount of space obtain from the system (both | |
3446 | via sbrk and mmap), the maximum amount (which may be more than | |
3447 | current if malloc_trim and/or munmap got called), the maximum | |
3448 | number of simultaneous mmap regions used, and the current number | |
3449 | of bytes allocated via malloc (or realloc, etc) but not yet | |
3450 | freed. (Note that this is the number of bytes allocated, not the | |
3451 | number requested. It will be larger than the number requested | |
3452 | because of alignment and bookkeeping overhead.) | |
3453 | ||
3454 | */ | |
3455 | ||
3456 | #if __STD_C | |
3457 | void malloc_stats(RONEARG) | |
3458 | #else | |
3459 | void malloc_stats(RONEARG) RDECL | |
3460 | #endif | |
3461 | { | |
3462 | unsigned long local_max_total_mem; | |
3463 | int local_sbrked_mem; | |
3464 | struct mallinfo local_mallinfo; | |
3465 | #if HAVE_MMAP | |
3466 | unsigned long local_mmapped_mem, local_max_n_mmaps; | |
3467 | #endif | |
3468 | FILE *fp; | |
3469 | ||
3470 | MALLOC_LOCK; | |
3471 | malloc_update_mallinfo(); | |
3472 | local_max_total_mem = max_total_mem; | |
3473 | local_sbrked_mem = sbrked_mem; | |
3474 | local_mallinfo = current_mallinfo; | |
3475 | #if HAVE_MMAP | |
3476 | local_mmapped_mem = mmapped_mem; | |
3477 | local_max_n_mmaps = max_n_mmaps; | |
3478 | #endif | |
3479 | MALLOC_UNLOCK; | |
3480 | ||
3481 | #ifdef INTERNAL_NEWLIB | |
8195aff7 | 3482 | _REENT_SMALL_CHECK_INIT(_stderr_r (reent_ptr)); |
8a0efa53 CF |
3483 | fp = _stderr_r(reent_ptr); |
3484 | #define fprintf fiprintf | |
3485 | #else | |
3486 | fp = stderr; | |
3487 | #endif | |
3488 | ||
3489 | fprintf(fp, "max system bytes = %10u\n", | |
3490 | (unsigned int)(local_max_total_mem)); | |
3491 | #if HAVE_MMAP | |
3492 | fprintf(fp, "system bytes = %10u\n", | |
3493 | (unsigned int)(local_sbrked_mem + local_mmapped_mem)); | |
3494 | fprintf(fp, "in use bytes = %10u\n", | |
3495 | (unsigned int)(local_mallinfo.uordblks + local_mmapped_mem)); | |
3496 | #else | |
3497 | fprintf(fp, "system bytes = %10u\n", | |
3498 | (unsigned int)local_sbrked_mem); | |
3499 | fprintf(fp, "in use bytes = %10u\n", | |
3500 | (unsigned int)local_mallinfo.uordblks); | |
3501 | #endif | |
3502 | #if HAVE_MMAP | |
3503 | fprintf(fp, "max mmap regions = %10u\n", | |
3504 | (unsigned int)local_max_n_mmaps); | |
3505 | #endif | |
3506 | } | |
3507 | ||
3508 | #endif /* DEFINE_MALLOC_STATS */ | |
3509 | ||
3510 | #ifdef DEFINE_MALLINFO | |
3511 | ||
3512 | /* | |
3513 | mallinfo returns a copy of updated current mallinfo. | |
3514 | */ | |
3515 | ||
3516 | #if __STD_C | |
3517 | struct mallinfo mALLINFo(RONEARG) | |
3518 | #else | |
3519 | struct mallinfo mALLINFo(RONEARG) RDECL | |
3520 | #endif | |
3521 | { | |
3522 | struct mallinfo ret; | |
3523 | ||
3524 | MALLOC_LOCK; | |
3525 | malloc_update_mallinfo(); | |
3526 | ret = current_mallinfo; | |
3527 | MALLOC_UNLOCK; | |
3528 | return ret; | |
3529 | } | |
3530 | ||
3531 | #endif /* DEFINE_MALLINFO */ | |
3532 | \f | |
3533 | #ifdef DEFINE_MALLOPT | |
3534 | ||
3535 | /* | |
3536 | mallopt: | |
3537 | ||
3538 | mallopt is the general SVID/XPG interface to tunable parameters. | |
3539 | The format is to provide a (parameter-number, parameter-value) pair. | |
3540 | mallopt then sets the corresponding parameter to the argument | |
3541 | value if it can (i.e., so long as the value is meaningful), | |
3542 | and returns 1 if successful else 0. | |
3543 | ||
3544 | See descriptions of tunable parameters above. | |
3545 | ||
3546 | */ | |
3547 | ||
3548 | #if __STD_C | |
3549 | int mALLOPt(RARG int param_number, int value) | |
3550 | #else | |
3551 | int mALLOPt(RARG param_number, value) RDECL int param_number; int value; | |
3552 | #endif | |
3553 | { | |
3554 | MALLOC_LOCK; | |
3555 | switch(param_number) | |
3556 | { | |
3557 | case M_TRIM_THRESHOLD: | |
3558 | trim_threshold = value; MALLOC_UNLOCK; return 1; | |
3559 | case M_TOP_PAD: | |
3560 | top_pad = value; MALLOC_UNLOCK; return 1; | |
3561 | case M_MMAP_THRESHOLD: | |
3562 | #if HAVE_MMAP | |
3563 | mmap_threshold = value; | |
3564 | #endif | |
3565 | MALLOC_UNLOCK; | |
3566 | return 1; | |
3567 | case M_MMAP_MAX: | |
3568 | #if HAVE_MMAP | |
3569 | n_mmaps_max = value; MALLOC_UNLOCK; return 1; | |
3570 | #else | |
3571 | MALLOC_UNLOCK; return value == 0; | |
3572 | #endif | |
3573 | ||
3574 | default: | |
3575 | MALLOC_UNLOCK; | |
3576 | return 0; | |
3577 | } | |
3578 | } | |
3579 | ||
3580 | #endif /* DEFINE_MALLOPT */ | |
3581 | ||
3582 | /* | |
3583 | ||
3584 | History: | |
3585 | ||
3586 | V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee) | |
3587 | * Added pvalloc, as recommended by H.J. Liu | |
3588 | * Added 64bit pointer support mainly from Wolfram Gloger | |
3589 | * Added anonymously donated WIN32 sbrk emulation | |
3590 | * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen | |
3591 | * malloc_extend_top: fix mask error that caused wastage after | |
3592 | foreign sbrks | |
3593 | * Add linux mremap support code from HJ Liu | |
3594 | ||
3595 | V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee) | |
3596 | * Integrated most documentation with the code. | |
3597 | * Add support for mmap, with help from | |
3598 | Wolfram Gloger (Gloger@lrz.uni-muenchen.de). | |
3599 | * Use last_remainder in more cases. | |
3600 | * Pack bins using idea from colin@nyx10.cs.du.edu | |
3601 | * Use ordered bins instead of best-fit threshhold | |
3602 | * Eliminate block-local decls to simplify tracing and debugging. | |
3603 | * Support another case of realloc via move into top | |
3604 | * Fix error occuring when initial sbrk_base not word-aligned. | |
3605 | * Rely on page size for units instead of SBRK_UNIT to | |
3606 | avoid surprises about sbrk alignment conventions. | |
3607 | * Add mallinfo, mallopt. Thanks to Raymond Nijssen | |
3608 | (raymond@es.ele.tue.nl) for the suggestion. | |
3609 | * Add `pad' argument to malloc_trim and top_pad mallopt parameter. | |
3610 | * More precautions for cases where other routines call sbrk, | |
3611 | courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de). | |
3612 | * Added macros etc., allowing use in linux libc from | |
3613 | H.J. Lu (hjl@gnu.ai.mit.edu) | |
3614 | * Inverted this history list | |
3615 | ||
3616 | V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee) | |
3617 | * Re-tuned and fixed to behave more nicely with V2.6.0 changes. | |
3618 | * Removed all preallocation code since under current scheme | |
3619 | the work required to undo bad preallocations exceeds | |
3620 | the work saved in good cases for most test programs. | |
3621 | * No longer use return list or unconsolidated bins since | |
3622 | no scheme using them consistently outperforms those that don't | |
3623 | given above changes. | |
3624 | * Use best fit for very large chunks to prevent some worst-cases. | |
3625 | * Added some support for debugging | |
3626 | ||
3627 | V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee) | |
3628 | * Removed footers when chunks are in use. Thanks to | |
3629 | Paul Wilson (wilson@cs.texas.edu) for the suggestion. | |
3630 | ||
3631 | V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee) | |
3632 | * Added malloc_trim, with help from Wolfram Gloger | |
3633 | (wmglo@Dent.MED.Uni-Muenchen.DE). | |
3634 | ||
3635 | V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g) | |
3636 | ||
3637 | V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g) | |
3638 | * realloc: try to expand in both directions | |
3639 | * malloc: swap order of clean-bin strategy; | |
3640 | * realloc: only conditionally expand backwards | |
3641 | * Try not to scavenge used bins | |
3642 | * Use bin counts as a guide to preallocation | |
3643 | * Occasionally bin return list chunks in first scan | |
3644 | * Add a few optimizations from colin@nyx10.cs.du.edu | |
3645 | ||
3646 | V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g) | |
3647 | * faster bin computation & slightly different binning | |
3648 | * merged all consolidations to one part of malloc proper | |
3649 | (eliminating old malloc_find_space & malloc_clean_bin) | |
3650 | * Scan 2 returns chunks (not just 1) | |
3651 | * Propagate failure in realloc if malloc returns 0 | |
3652 | * Add stuff to allow compilation on non-ANSI compilers | |
3653 | from kpv@research.att.com | |
3654 | ||
3655 | V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu) | |
3656 | * removed potential for odd address access in prev_chunk | |
3657 | * removed dependency on getpagesize.h | |
3658 | * misc cosmetics and a bit more internal documentation | |
3659 | * anticosmetics: mangled names in macros to evade debugger strangeness | |
3660 | * tested on sparc, hp-700, dec-mips, rs6000 | |
3661 | with gcc & native cc (hp, dec only) allowing | |
3662 | Detlefs & Zorn comparison study (in SIGPLAN Notices.) | |
3663 | ||
3664 | Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu) | |
3665 | * Based loosely on libg++-1.2X malloc. (It retains some of the overall | |
3666 | structure of old version, but most details differ.) | |
3667 | ||
3668 | */ | |
3669 | #endif |