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comparison src/malloc.c @ 428:3ecd8885ac67 r21-2-22

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date Mon, 13 Aug 2007 11:28:15 +0200
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1 /* dynamic memory allocation for GNU.
2 Copyright (C) 1985, 1987 Free Software Foundation, Inc.
3
4 NO WARRANTY
5
6 BECAUSE THIS PROGRAM IS LICENSED FREE OF CHARGE, WE PROVIDE ABSOLUTELY
7 NO WARRANTY, TO THE EXTENT PERMITTED BY APPLICABLE STATE LAW. EXCEPT
8 WHEN OTHERWISE STATED IN WRITING, FREE SOFTWARE FOUNDATION, INC,
9 RICHARD M. STALLMAN AND/OR OTHER PARTIES PROVIDE THIS PROGRAM "AS IS"
10 WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
11 BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
12 FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY
13 AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE
14 DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR
15 CORRECTION.
16
17 IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW WILL RICHARD M.
18 STALLMAN, THE FREE SOFTWARE FOUNDATION, INC., AND/OR ANY OTHER PARTY
19 WHO MAY MODIFY AND REDISTRIBUTE THIS PROGRAM AS PERMITTED BELOW, BE
20 LIABLE TO YOU FOR DAMAGES, INCLUDING ANY LOST PROFITS, LOST MONIES, OR
21 OTHER SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
22 USE OR INABILITY TO USE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR
23 DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY THIRD PARTIES OR
24 A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS) THIS
25 PROGRAM, EVEN IF YOU HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH
26 DAMAGES, OR FOR ANY CLAIM BY ANY OTHER PARTY.
27
28 GENERAL PUBLIC LICENSE TO COPY
29
30 1. You may copy and distribute verbatim copies of this source file
31 as you receive it, in any medium, provided that you conspicuously and
32 appropriately publish on each copy a valid copyright notice "Copyright
33 (C) 1985 Free Software Foundation, Inc."; and include following the
34 copyright notice a verbatim copy of the above disclaimer of warranty
35 and of this License. You may charge a distribution fee for the
36 physical act of transferring a copy.
37
38 2. You may modify your copy or copies of this source file or
39 any portion of it, and copy and distribute such modifications under
40 the terms of Paragraph 1 above, provided that you also do the following:
41
42 a) cause the modified files to carry prominent notices stating
43 that you changed the files and the date of any change; and
44
45 b) cause the whole of any work that you distribute or publish,
46 that in whole or in part contains or is a derivative of this
47 program or any part thereof, to be licensed at no charge to all
48 third parties on terms identical to those contained in this
49 License Agreement (except that you may choose to grant more extensive
50 warranty protection to some or all third parties, at your option).
51
52 c) You may charge a distribution fee for the physical act of
53 transferring a copy, and you may at your option offer warranty
54 protection in exchange for a fee.
55
56 Mere aggregation of another unrelated program with this program (or its
57 derivative) on a volume of a storage or distribution medium does not bring
58 the other program under the scope of these terms.
59
60 3. You may copy and distribute this program (or a portion or derivative
61 of it, under Paragraph 2) in object code or executable form under the terms
62 of Paragraphs 1 and 2 above provided that you also do one of the following:
63
64 a) accompany it with the complete corresponding machine-readable
65 source code, which must be distributed under the terms of
66 Paragraphs 1 and 2 above; or,
67
68 b) accompany it with a written offer, valid for at least three
69 years, to give any third party free (except for a nominal
70 shipping charge) a complete machine-readable copy of the
71 corresponding source code, to be distributed under the terms of
72 Paragraphs 1 and 2 above; or,
73
74 c) accompany it with the information you received as to where the
75 corresponding source code may be obtained. (This alternative is
76 allowed only for noncommercial distribution and only if you
77 received the program in object code or executable form alone.)
78
79 For an executable file, complete source code means all the source code for
80 all modules it contains; but, as a special exception, it need not include
81 source code for modules which are standard libraries that accompany the
82 operating system on which the executable file runs.
83
84 4. You may not copy, sublicense, distribute or transfer this program
85 except as expressly provided under this License Agreement. Any attempt
86 otherwise to copy, sublicense, distribute or transfer this program is void and
87 your rights to use the program under this License agreement shall be
88 automatically terminated. However, parties who have received computer
89 software programs from you with this License Agreement will not have
90 their licenses terminated so long as such parties remain in full compliance.
91
92 5. If you wish to incorporate parts of this program into other free
93 programs whose distribution conditions are different, write to the
94 Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
95 MA 02111-1307, USA.. We have not yet worked out a simple rule that
96 can be stated here, but we will often permit this. We will be guided
97 by the two goals of preserving the free status of all derivatives of
98 our free software and of promoting the sharing and reuse of software.
99
100
101 In other words, you are welcome to use, share and improve this program.
102 You are forbidden to forbid anyone else to use, share and improve
103 what you give them. Help stamp out software-hoarding! */
104
105 /* Synched up with: Not synched with FSF. */
106
107
108 /*
109 * @(#)nmalloc.c 1 (Caltech) 2/21/82
110 *
111 * U of M Modified: 20 Jun 1983 ACT: strange hacks for Emacs
112 *
113 * Nov 1983, Mike@BRL, Added support for 4.1C/4.2 BSD.
114 *
115 * This is a very fast storage allocator. It allocates blocks of a small
116 * number of different sizes, and keeps free lists of each size. Blocks
117 * that don't exactly fit are passed up to the next larger size. In this
118 * implementation, the available sizes are (2^n)-4 (or -16) bytes long.
119 * This is designed for use in a program that uses vast quantities of
120 * memory, but bombs when it runs out. To make it a little better, it
121 * warns the user when he starts to get near the end.
122 *
123 * June 84, ACT: modified rcheck code to check the range given to malloc,
124 * rather than the range determined by the 2-power used.
125 *
126 * Jan 85, RMS: calls malloc_warning to issue warning on nearly full.
127 * No longer Emacs-specific; can serve as all-purpose malloc for GNU.
128 * You should call malloc_init to reinitialize after loading dumped Emacs.
129 * Call malloc_stats to get info on memory stats if MSTATS turned on.
130 * realloc knows how to return same block given, just changing its size,
131 * if the power of 2 is correct.
132 */
133
134 /*
135 * nextf[i] is the pointer to the next free block of size 2^(i+3). The
136 * smallest allocatable block is 8 bytes. The overhead information will
137 * go in the first int of the block, and the returned pointer will point
138 * to the second.
139 *
140 #ifdef MSTATS
141 * nmalloc[i] is the difference between the number of mallocs and frees
142 * for a given block size.
143 #endif MSTATS
144 */
145
146 #ifdef emacs
147 /* config.h specifies which kind of system this is. */
148 #include <config.h>
149 #else
150
151 /* Determine which kind of system this is. */
152 #include <signal.h>
153 #ifndef SIGTSTP
154 #ifndef USG
155 #define USG
156 #endif
157 #else /* SIGTSTP */
158 #ifdef SIGIO
159 #define BSD4_2
160 #endif /* SIGIO */
161 #endif /* SIGTSTP */
162
163 #if defined(hpux)
164 #define USG
165 #endif
166
167 #endif /* not emacs */
168
169 #include <stddef.h>
170
171 /* Define getpagesize () if the system does not. */
172 #include "getpagesize.h"
173
174 #ifdef HAVE_ULIMIT_H
175 #include <ulimit.h>
176 #endif
177
178 #ifndef BSD4_2
179 #ifndef USG
180 #include <sys/vlimit.h> /* warn the user when near the end */
181 #endif /* not USG */
182 #else /* if BSD4_2 */
183 #include <sys/time.h>
184 #include <sys/resource.h>
185 #endif /* BSD4_2 */
186
187 #ifdef __STDC__
188 #ifndef HPUX
189 /* not sure where this for NetBSD should really go
190 and it probably applies to other systems */
191 #if !defined(__NetBSD__) && !defined(__bsdi__) && !defined(__OpenBSD__)
192 extern void *sbrk (ptrdiff_t);
193 #else
194 extern char *sbrk ();
195 #endif /* __NetBSD__ or __OpenBSD__ */
196 #endif /* HPUX */
197 #else
198 extern void *sbrk ();
199 #endif /* __STDC__ */
200
201 extern char *start_of_data (void);
202
203 #ifdef BSD
204 #ifndef DATA_SEG_BITS
205 #define start_of_data() &etext
206 #endif
207 #endif
208
209 #ifndef emacs
210 #define start_of_data() &etext
211 #endif
212
213 #define ISALLOC ((char) 0xf7) /* magic byte that implies allocation */
214 #define ISFREE ((char) 0x54) /* magic byte that implies free block */
215 /* this is for error checking only */
216 #define ISMEMALIGN ((char) 0xd6) /* Stored before the value returned by
217 memalign, with the rest of the word
218 being the distance to the true
219 beginning of the block. */
220
221 extern char etext;
222
223 /* These two are for user programs to look at, when they are interested. */
224
225 unsigned int malloc_sbrk_used; /* amount of data space used now */
226 unsigned int malloc_sbrk_unused; /* amount more we can have */
227
228 /* start of data space; can be changed by calling init_malloc */
229 static char *data_space_start;
230
231 #ifdef MSTATS
232 static int nmalloc[30];
233 static int nmal, nfre;
234 #endif /* MSTATS */
235
236 /* If range checking is not turned on, all we have is a flag indicating
237 whether memory is allocated, an index in nextf[], and a size field; to
238 realloc() memory we copy either size bytes or 1<<(index+3) bytes depending
239 on whether the former can hold the exact size (given the value of
240 'index'). If range checking is on, we always need to know how much space
241 is allocated, so the 'size' field is never used. */
242
243 struct mhead {
244 char mh_alloc; /* ISALLOC or ISFREE */
245 char mh_index; /* index in nextf[] */
246 /* Remainder are valid only when block is allocated */
247 unsigned short mh_size; /* size, if < 0x10000 */
248 #ifdef rcheck
249 unsigned mh_nbytes; /* number of bytes allocated */
250 int mh_magic4; /* should be == MAGIC4 */
251 #endif /* rcheck */
252 };
253
254 /* Access free-list pointer of a block.
255 It is stored at block + 4.
256 This is not a field in the mhead structure
257 because we want sizeof (struct mhead)
258 to describe the overhead for when the block is in use,
259 and we do not want the free-list pointer to count in that. */
260
261 #define CHAIN(a) \
262 (*(struct mhead **) (sizeof (char *) + (char *) (a)))
263
264 #ifdef rcheck
265
266 /* To implement range checking, we write magic values in at the beginning and
267 end of each allocated block, and make sure they are undisturbed whenever a
268 free or a realloc occurs. */
269 /* Written in each of the 4 bytes following the block's real space */
270 #define MAGIC1 0x55
271 /* Written in the 4 bytes before the block's real space */
272 #define MAGIC4 0x55555555
273 #define ASSERT(p) if (!(p)) botch("p"); else
274 #define EXTRA 4 /* 4 bytes extra for MAGIC1s */
275 #else
276 #define ASSERT(p)
277 #define EXTRA 0
278 #endif /* rcheck */
279
280
281 /* nextf[i] is free list of blocks of size 2**(i + 3) */
282
283 static struct mhead *nextf[30];
284
285 /* busy[i] is nonzero while allocation of block size i is in progress. */
286
287 static char busy[30];
288
289 /* Number of bytes of writable memory we can expect to be able to get */
290 extern unsigned int lim_data;
291
292 /* Level number of warnings already issued.
293 0 -- no warnings issued.
294 1 -- 75% warning already issued.
295 2 -- 85% warning already issued.
296 */
297 static int warnlevel;
298
299 /* Function to call to issue a warning;
300 0 means don't issue them. */
301 static void (*warnfunction) ();
302
303 /* nonzero once initial bunch of free blocks made */
304 static int gotpool;
305
306 char *_malloc_base;
307
308 static void getpool (void);
309
310 /* Cause reinitialization based on job parameters;
311 also declare where the end of pure storage is. */
312 void
313 malloc_init (start, warnfun)
314 char *start;
315 void (*warnfun) ();
316 {
317 if (start)
318 data_space_start = start;
319 lim_data = 0;
320 warnlevel = 0;
321 warnfunction = warnfun;
322 }
323
324 /* Return the maximum size to which MEM can be realloc'd
325 without actually requiring copying. */
326
327 int
328 malloc_usable_size (mem)
329 char *mem;
330 {
331 int blocksize = 8 << (((struct mhead *) mem) - 1) -> mh_index;
332
333 return blocksize - sizeof (struct mhead) - EXTRA;
334 }
335
336 static void get_lim_data ();
337
338 static void
339 morecore (nu) /* ask system for more memory */
340 int nu; /* size index to get more of */
341 {
342 char *cp;
343 int nblks;
344 unsigned int siz;
345 int oldmask;
346
347 #ifdef BSD
348 #ifndef BSD4_1
349 /* ?? There was a suggestion not to block SIGILL, somehow for GDB's sake. */
350 oldmask = sigsetmask (-1);
351 #endif
352 #endif
353
354 if (!data_space_start)
355 {
356 data_space_start = start_of_data ();
357 }
358
359 if (lim_data == 0)
360 get_lim_data ();
361
362 /* On initial startup, get two blocks of each size up to 1k bytes */
363 if (!gotpool)
364 { getpool (); getpool (); gotpool = 1; }
365
366 /* Find current end of memory and issue warning if getting near max */
367
368 cp = sbrk (0);
369 siz = cp - data_space_start;
370
371 if (warnfunction)
372 switch (warnlevel)
373 {
374 case 0:
375 if (siz > (lim_data / 4) * 3)
376 {
377 warnlevel++;
378 (*warnfunction) ("Warning: past 75% of memory limit");
379 }
380 break;
381 case 1:
382 if (siz > (lim_data / 20) * 17)
383 {
384 warnlevel++;
385 (*warnfunction) ("Warning: past 85% of memory limit");
386 }
387 break;
388 case 2:
389 if (siz > (lim_data / 20) * 19)
390 {
391 warnlevel++;
392 (*warnfunction) ("Warning: past 95% of memory limit");
393 }
394 break;
395 }
396
397 if ((int) cp & 0x3ff) /* land on 1K boundaries */
398 sbrk (1024 - ((int) cp & 0x3ff));
399
400 /* Take at least 2k, and figure out how many blocks of the desired size
401 we're about to get */
402 nblks = 1;
403 if ((siz = nu) < 8)
404 nblks = 1 << ((siz = 8) - nu);
405
406 if ((cp = sbrk (1 << (siz + 3))) == (char *) -1)
407 {
408 #ifdef BSD
409 #ifndef BSD4_1
410 sigsetmask (oldmask);
411 #endif
412 #endif
413 return; /* no more room! */
414 }
415 malloc_sbrk_used = siz;
416 malloc_sbrk_unused = lim_data - siz;
417
418 if ((int) cp & 7)
419 { /* shouldn't happen, but just in case */
420 cp = (char *) (((int) cp + 8) & ~7);
421 nblks--;
422 }
423
424 /* save new header and link the nblks blocks together */
425 nextf[nu] = (struct mhead *) cp;
426 siz = 1 << (nu + 3);
427 while (1)
428 {
429 ((struct mhead *) cp) -> mh_alloc = ISFREE;
430 ((struct mhead *) cp) -> mh_index = nu;
431 if (--nblks <= 0) break;
432 CHAIN ((struct mhead *) cp) = (struct mhead *) (cp + siz);
433 cp += siz;
434 }
435 CHAIN ((struct mhead *) cp) = 0;
436
437 #ifdef BSD
438 #ifndef BSD4_1
439 sigsetmask (oldmask);
440 #endif
441 #endif
442 }
443
444 static void
445 getpool (void)
446 {
447 int nu;
448 char *cp = sbrk (0);
449
450 if ((int) cp & 0x3ff) /* land on 1K boundaries */
451 sbrk (1024 - ((int) cp & 0x3ff));
452
453 /* Record address of start of space allocated by malloc. */
454 if (_malloc_base == 0)
455 _malloc_base = cp;
456
457 /* Get 2k of storage */
458
459 cp = sbrk (04000);
460 if (cp == (char *) -1)
461 return;
462
463 /* Divide it into an initial 8-word block
464 plus one block of size 2**nu for nu = 3 ... 10. */
465
466 CHAIN (cp) = nextf[0];
467 nextf[0] = (struct mhead *) cp;
468 ((struct mhead *) cp) -> mh_alloc = ISFREE;
469 ((struct mhead *) cp) -> mh_index = 0;
470 cp += 8;
471
472 for (nu = 0; nu < 7; nu++)
473 {
474 CHAIN (cp) = nextf[nu];
475 nextf[nu] = (struct mhead *) cp;
476 ((struct mhead *) cp) -> mh_alloc = ISFREE;
477 ((struct mhead *) cp) -> mh_index = nu;
478 cp += 8 << nu;
479 }
480 }
481
482 char *
483 malloc (n) /* get a block */
484 unsigned n;
485 {
486 struct mhead *p;
487 unsigned int nbytes;
488 int nunits = 0;
489
490 /* Figure out how many bytes are required, rounding up to the nearest
491 multiple of 8, then figure out which nestf[] area to use.
492 Both the beginning of the header and the beginning of the
493 block should be on an eight byte boundary. */
494 nbytes = (n + ((sizeof *p + 7) & ~7) + EXTRA + 7) & ~7;
495 {
496 unsigned int shiftr = (nbytes - 1) >> 2;
497
498 while (shiftr >>= 1)
499 nunits++;
500 }
501
502 /* In case this is reentrant use of malloc from signal handler,
503 pick a block size that no other malloc level is currently
504 trying to allocate. That's the easiest harmless way not to
505 interfere with the other level of execution. */
506 while (busy[nunits]) nunits++;
507 busy[nunits] = 1;
508
509 /* If there are no blocks of the appropriate size, go get some */
510 /* COULD SPLIT UP A LARGER BLOCK HERE ... ACT */
511 if (nextf[nunits] == 0)
512 morecore (nunits);
513
514 /* Get one block off the list, and set the new list head */
515 if ((p = nextf[nunits]) == 0)
516 {
517 busy[nunits] = 0;
518 return 0;
519 }
520 nextf[nunits] = CHAIN (p);
521 busy[nunits] = 0;
522
523 /* Check for free block clobbered */
524 /* If not for this check, we would gobble a clobbered free chain ptr */
525 /* and bomb out on the NEXT allocate of this size block */
526 if (p -> mh_alloc != ISFREE || p -> mh_index != nunits)
527 #ifdef rcheck
528 botch ("block on free list clobbered");
529 #else /* not rcheck */
530 abort ();
531 #endif /* not rcheck */
532
533 /* Fill in the info, and if range checking, set up the magic numbers */
534 p -> mh_alloc = ISALLOC;
535 #ifdef rcheck
536 p -> mh_nbytes = n;
537 p -> mh_magic4 = MAGIC4;
538 {
539 /* Get the location n after the beginning of the user's space. */
540 char *m = (char *) p + ((sizeof *p + 7) & ~7) + n;
541
542 *m++ = MAGIC1, *m++ = MAGIC1, *m++ = MAGIC1, *m = MAGIC1;
543 }
544 #else /* not rcheck */
545 p -> mh_size = n;
546 #endif /* not rcheck */
547 #ifdef MSTATS
548 nmalloc[nunits]++;
549 nmal++;
550 #endif /* MSTATS */
551 return (char *) p + ((sizeof *p + 7) & ~7);
552 }
553
554 void
555 free (mem)
556 char *mem;
557 {
558 struct mhead *p;
559 {
560 char *ap = mem;
561
562 if (ap == 0)
563 return;
564
565 p = (struct mhead *) (ap - ((sizeof *p + 7) & ~7));
566 if (p -> mh_alloc == ISMEMALIGN)
567 {
568 ap -= p->mh_size;
569 p = (struct mhead *) (ap - ((sizeof *p + 7) & ~7));
570 }
571
572 #ifndef rcheck
573 if (p -> mh_alloc != ISALLOC)
574 abort ();
575
576 #else /* rcheck */
577 if (p -> mh_alloc != ISALLOC)
578 {
579 if (p -> mh_alloc == ISFREE)
580 botch ("free: Called with already freed block argument\n");
581 else
582 botch ("free: Called with bad argument\n");
583 }
584
585 ASSERT (p -> mh_magic4 == MAGIC4);
586 ap += p -> mh_nbytes;
587 ASSERT (*ap++ == MAGIC1); ASSERT (*ap++ == MAGIC1);
588 ASSERT (*ap++ == MAGIC1); ASSERT (*ap == MAGIC1);
589 #endif /* rcheck */
590 }
591 {
592 int nunits = p -> mh_index;
593
594 ASSERT (nunits <= 29);
595 p -> mh_alloc = ISFREE;
596
597 /* Protect against signal handlers calling malloc. */
598 busy[nunits] = 1;
599 /* Put this block on the free list. */
600 CHAIN (p) = nextf[nunits];
601 nextf[nunits] = p;
602 busy[nunits] = 0;
603
604 #ifdef MSTATS
605 nmalloc[nunits]--;
606 nfre++;
607 #endif /* MSTATS */
608 }
609 }
610
611 char *
612 realloc (mem, n)
613 char *mem;
614 unsigned n;
615 {
616 struct mhead *p;
617 unsigned int tocopy;
618 unsigned int nbytes;
619 int nunits;
620
621 if (mem == 0)
622 return malloc (n);
623 p = (struct mhead *) (mem - ((sizeof *p + 7) & ~7));
624 nunits = p -> mh_index;
625 ASSERT (p -> mh_alloc == ISALLOC);
626 #ifdef rcheck
627 ASSERT (p -> mh_magic4 == MAGIC4);
628 {
629 char *m = mem + (tocopy = p -> mh_nbytes);
630 ASSERT (*m++ == MAGIC1); ASSERT (*m++ == MAGIC1);
631 ASSERT (*m++ == MAGIC1); ASSERT (*m == MAGIC1);
632 }
633 #else /* not rcheck */
634 if (p -> mh_index >= 13)
635 tocopy = (1 << (p -> mh_index + 3)) - ((sizeof *p + 7) & ~7);
636 else
637 tocopy = p -> mh_size;
638 #endif /* not rcheck */
639
640 /* See if desired size rounds to same power of 2 as actual size. */
641 nbytes = (n + ((sizeof *p + 7) & ~7) + EXTRA + 7) & ~7;
642
643 /* If ok, use the same block, just marking its size as changed. */
644 if (nbytes > (4 << nunits) && nbytes <= (8 << nunits))
645 {
646 #ifdef rcheck
647 char *m = mem + tocopy;
648 *m++ = 0; *m++ = 0; *m++ = 0; *m++ = 0;
649 p-> mh_nbytes = n;
650 m = mem + n;
651 *m++ = MAGIC1; *m++ = MAGIC1; *m++ = MAGIC1; *m++ = MAGIC1;
652 #else /* not rcheck */
653 p -> mh_size = n;
654 #endif /* not rcheck */
655 return mem;
656 }
657
658 if (n < tocopy)
659 tocopy = n;
660 {
661 char *new;
662
663 if ((new = malloc (n)) == 0)
664 return 0;
665 memcpy (new, mem, tocopy);
666 free (mem);
667 return new;
668 }
669 }
670
671
672 char *
673 memalign (alignment, size)
674 unsigned alignment, size;
675 {
676 char *ptr = malloc (size + alignment);
677 char *aligned;
678 struct mhead *p;
679
680 if (ptr == 0)
681 return 0;
682 /* If entire block has the desired alignment, just accept it. */
683 if (((int) ptr & (alignment - 1)) == 0)
684 return ptr;
685 /* Otherwise, get address of byte in the block that has that alignment. */
686 aligned = (char *) (((int) ptr + alignment - 1) & -alignment);
687
688 /* Store a suitable indication of how to free the block,
689 so that free can find the true beginning of it. */
690 p = (struct mhead *) aligned - 1;
691 p -> mh_size = aligned - ptr;
692 p -> mh_alloc = ISMEMALIGN;
693 return aligned;
694 }
695
696 #ifndef __hpux
697 /* This runs into trouble with getpagesize on HPUX.
698 Patching out seems cleaner than the ugly fix needed. */
699 char *
700 valloc (size)
701 unsigned size;
702 {
703 return memalign (getpagesize (), size);
704 }
705 #endif /* not __hpux */
706
707 #ifdef MSTATS
708 /* Return statistics describing allocation of blocks of size 2**n. */
709
710 struct mstats_value
711 {
712 int blocksize;
713 int nfree;
714 int nused;
715 };
716
717 struct mstats_value
718 malloc_stats (size)
719 int size;
720 {
721 struct mstats_value v;
722 int i;
723 struct mhead *p;
724
725 v.nfree = 0;
726
727 if (size < 0 || size >= 30)
728 {
729 v.blocksize = 0;
730 v.nused = 0;
731 return v;
732 }
733
734 v.blocksize = 1 << (size + 3);
735 v.nused = nmalloc[size];
736
737 for (p = nextf[size]; p; p = CHAIN (p))
738 v.nfree++;
739
740 return v;
741 }
742 int
743 malloc_mem_used ()
744 {
745 int i;
746 int size_used;
747
748 size_used = 0;
749
750 for (i = 0; i < 30; i++)
751 {
752 int allocation_size = 1 << (i + 3);
753 struct mhead *p;
754
755 size_used += nmalloc[i] * allocation_size;
756 }
757
758 return size_used;
759 }
760
761 int
762 malloc_mem_free ()
763 {
764 int i;
765 int size_unused;
766
767 size_unused = 0;
768
769 for (i = 0; i < 30; i++)
770 {
771 int allocation_size = 1 << (i + 3);
772 struct mhead *p;
773
774 for (p = nextf[i]; p ; p = CHAIN (p))
775 size_unused += allocation_size;
776 }
777
778 return size_unused;
779 }
780 #endif /* MSTATS */
781
782 /*
783 * This function returns the total number of bytes that the process
784 * will be allowed to allocate via the sbrk(2) system call. On
785 * BSD systems this is the total space allocatable to stack and
786 * data. On USG systems this is the data space only.
787 */
788
789 #ifdef USG
790
791 static void
792 get_lim_data ()
793 {
794 #ifdef ULIMIT_BREAK_VALUE
795 lim_data = ULIMIT_BREAK_VALUE;
796 #else
797 lim_data = ulimit (3, 0);
798 #endif
799
800 lim_data -= (long) data_space_start;
801 }
802
803 #else /* not USG */
804 #ifndef BSD4_2
805
806 static void
807 get_lim_data ()
808 {
809 lim_data = vlimit (LIM_DATA, -1);
810 }
811
812 #else /* BSD4_2 */
813
814 static void
815 get_lim_data ()
816 {
817 struct rlimit XXrlimit;
818
819 getrlimit (RLIMIT_DATA, &XXrlimit);
820 #ifdef RLIM_INFINITY
821 lim_data = XXrlimit.rlim_cur & RLIM_INFINITY; /* soft limit */
822 #else
823 lim_data = XXrlimit.rlim_cur; /* soft limit */
824 #endif
825 }
826
827 #endif /* BSD4_2 */
828 #endif /* not USG */
829