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authortholo <>1996-08-02 18:08:09 +0000
committertholo <>1996-08-02 18:08:09 +0000
commitad6b9b4b5b85ac52952082177cd5495d10409382 (patch)
tree8afe95aa32a291a80aeb9f2e37cefd2ff2b8f327 /src
parentf16e645fccbb65fe48490c8afd7515b0ad5f31ee (diff)
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malloc(3) implementation from FreeBSD; uses mmap(2) to get memory
Diffstat (limited to 'src')
-rw-r--r--src/lib/libc/stdlib/malloc.c1523
1 files changed, 1158 insertions, 365 deletions
diff --git a/src/lib/libc/stdlib/malloc.c b/src/lib/libc/stdlib/malloc.c
index 612759d9b2..38938f96cf 100644
--- a/src/lib/libc/stdlib/malloc.c
+++ b/src/lib/libc/stdlib/malloc.c
@@ -1,430 +1,1223 @@
1/* $NetBSD: malloc.c,v 1.6 1996/01/17 02:45:25 jtc Exp $ */
2
3/* 1/*
4 * Copyright (c) 1983 Regents of the University of California. 2 * ----------------------------------------------------------------------------
5 * All rights reserved. 3 * "THE BEER-WARE LICENSE" (Revision 42):
4 * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you
5 * can do whatever you want with this stuff. If we meet some day, and you think
6 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
7 * ----------------------------------------------------------------------------
6 * 8 *
7 * Redistribution and use in source and binary forms, with or without 9 * $Id: malloc.c,v 1.4 1996/08/02 18:08:09 tholo Exp $
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by the University of
18 * California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 * 10 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 11 */
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 12
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 13/*
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 14 * Defining EXTRA_SANITY will enable some checks which are related
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 15 * to internal conditions and consistency in malloc.c
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 16 */
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 17#undef EXTRA_SANITY
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 18
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 19/*
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 20 * Defining MALLOC_STATS will enable you to call malloc_dump() and set
33 * SUCH DAMAGE. 21 * the [dD] options in the MALLOC_OPTIONS environment variable.
34 */ 22 * It has no run-time performance hit.
35 23 */
36#if defined(LIBC_SCCS) && !defined(lint) 24#define MALLOC_STATS
37#if 0 25
38static char *sccsid = "from: @(#)malloc.c 5.11 (Berkeley) 2/23/91"; 26#if defined(EXTRA_SANITY) && !defined(MALLOC_STATS)
39#else 27# define MALLOC_STATS /* required for EXTRA_SANITY */
40static char *rcsid = "$NetBSD: malloc.c,v 1.6 1996/01/17 02:45:25 jtc Exp $";
41#endif 28#endif
42#endif /* LIBC_SCCS and not lint */
43 29
44/* 30/*
45 * malloc.c (Caltech) 2/21/82 31 * What to use for Junk
46 * Chris Kingsley, kingsley@cit-20.
47 *
48 * This is a very fast storage allocator. It allocates blocks of a small
49 * number of different sizes, and keeps free lists of each size. Blocks that
50 * don't exactly fit are passed up to the next larger size. In this
51 * implementation, the available sizes are 2^n-4 (or 2^n-10) bytes long.
52 * This is designed for use in a virtual memory environment.
53 */ 32 */
33#define SOME_JUNK 0xd0 /* as in "Duh" :-) */
54 34
55#include <sys/types.h> 35#include <stdio.h>
56#include <stdlib.h> 36#include <stdlib.h>
57#include <string.h>
58#include <unistd.h> 37#include <unistd.h>
59 38#include <memory.h>
60#define NULL 0 39#include <errno.h>
61 40#include <err.h>
62/* 41#include <sys/types.h>
63 * The overhead on a block is at least 4 bytes. When free, this space 42#include <sys/param.h>
64 * contains a pointer to the next free block, and the bottom two bits must 43#include <sys/mman.h>
65 * be zero. When in use, the first byte is set to MAGIC, and the second 44#ifdef _THREAD_SAFE
66 * byte is the size index. The remaining bytes are for alignment. 45#include <pthread.h>
67 * If range checking is enabled then a second word holds the size of the 46#include "pthread_private.h"
68 * requested block, less 1, rounded up to a multiple of sizeof(RMAGIC).
69 * The order of elements is critical: ov_magic must overlay the low order
70 * bits of ov_next, and ov_magic can not be a valid ov_next bit pattern.
71 */
72union overhead {
73 union overhead *ov_next; /* when free */
74 struct {
75 u_char ovu_magic; /* magic number */
76 u_char ovu_index; /* bucket # */
77#ifdef RCHECK
78 u_short ovu_rmagic; /* range magic number */
79 u_long ovu_size; /* actual block size */
80#endif 47#endif
81 } ovu;
82#define ov_magic ovu.ovu_magic
83#define ov_index ovu.ovu_index
84#define ov_rmagic ovu.ovu_rmagic
85#define ov_size ovu.ovu_size
86};
87 48
88static void morecore __P((int)); 49/*
89static int findbucket __P((union overhead *, int)); 50 * If these weren't defined here, they would be calculated on the fly,
51 * at a considerable cost in performance.
52 */
53#ifdef __OpenBSD__
54# if defined(__alpha__) || defined(__m68k__) || defined(__mips__) || \
55 defined(__i386__) || defined(__m88k__) || defined(__ns32k__) || \
56 defined(__vax__)
57# define malloc_pagesize (NBPG)
58# define malloc_pageshift (PGSHIFT)
59# define malloc_maxsize (malloc_pagesize >> 1)
60# define malloc_minsize 16U
61# endif /* __i386__ */
62#endif /* __OpenBSD__ */
90 63
91#define MAGIC 0xef /* magic # on accounting info */ 64/*
92#define RMAGIC 0x5555 /* magic # on range info */ 65 * This structure describes a page worth of chunks.
66 */
93 67
94#ifdef RCHECK 68struct pginfo {
95#define RSLOP sizeof (u_short) 69 struct pginfo *next; /* next on the free list */
96#else 70 void *page; /* Pointer to the page */
97#define RSLOP 0 71 u_short size; /* size of this page's chunks */
98#endif 72 u_short shift; /* How far to shift for this size chunks */
73 u_short free; /* How many free chunks */
74 u_short total; /* How many chunk */
75 u_long bits[1]; /* Which chunks are free */
76};
99 77
100/* 78/*
101 * nextf[i] is the pointer to the next free block of size 2^(i+3). The 79 * This structure describes a number of free pages.
102 * smallest allocatable block is 8 bytes. The overhead information
103 * precedes the data area returned to the user.
104 */ 80 */
105#define NBUCKETS 30
106static union overhead *nextf[NBUCKETS];
107extern char *sbrk();
108 81
109static int pagesz; /* page size */ 82struct pgfree {
110static int pagebucket; /* page size bucket */ 83 struct pgfree *next; /* next run of free pages */
84 struct pgfree *prev; /* prev run of free pages */
85 void *page; /* pointer to free pages */
86 void *end; /* pointer to end of free pages */
87 u_long size; /* number of bytes free */
88};
111 89
112#ifdef MSTATS
113/* 90/*
114 * nmalloc[i] is the difference between the number of mallocs and frees 91 * How many bits per u_long in the bitmap.
115 * for a given block size. 92 * Change only if not 8 bits/byte
116 */ 93 */
117static u_int nmalloc[NBUCKETS]; 94#define MALLOC_BITS (8*sizeof(u_long))
118#include <stdio.h>
119#endif
120 95
121#if defined(DEBUG) || defined(RCHECK) 96/*
122#define ASSERT(p) if (!(p)) botch("p") 97 * Magic values to put in the page_directory
123#include <stdio.h> 98 */
124static 99#define MALLOC_NOT_MINE ((struct pginfo*) 0)
125botch(s) 100#define MALLOC_FREE ((struct pginfo*) 1)
126 char *s; 101#define MALLOC_FIRST ((struct pginfo*) 2)
102#define MALLOC_FOLLOW ((struct pginfo*) 3)
103#define MALLOC_MAGIC ((struct pginfo*) 4)
104
105/*
106 * The i386 architecture has some very convenient instructions.
107 * We might as well use them. There are C-language backups, but
108 * they are considerably slower.
109 */
110#ifdef __i386__
111#define ffs _ffs
112static __inline int
113_ffs(unsigned input)
127{ 114{
128 fprintf(stderr, "\r\nassertion botched: %s\r\n", s); 115 int result;
129 (void) fflush(stderr); /* just in case user buffered it */ 116 asm("bsfl %1,%0" : "=r" (result) : "r" (input));
130 abort(); 117 return result+1;
131} 118}
132#else
133#define ASSERT(p)
134#endif
135 119
136void * 120#define fls _fls
137malloc(nbytes) 121static __inline int
138 size_t nbytes; 122_fls(unsigned input)
123{
124 int result;
125 asm("bsrl %1,%0" : "=r" (result) : "r" (input));
126 return result+1;
127}
128
129#define set_bit _set_bit
130static __inline void
131_set_bit(struct pginfo *pi, int bit)
139{ 132{
140 register union overhead *op; 133 asm("btsl %0,(%1)" :
141 register long bucket, n; 134 : "r" (bit & (MALLOC_BITS-1)), "r" (pi->bits+(bit/MALLOC_BITS)));
142 register unsigned amt; 135}
143 136
144 /* 137#define clr_bit _clr_bit
145 * First time malloc is called, setup page size and 138static __inline void
146 * align break pointer so all data will be page aligned. 139_clr_bit(struct pginfo *pi, int bit)
147 */ 140{
148 if (pagesz == 0) { 141 asm("btcl %0,(%1)" :
149 pagesz = n = getpagesize(); 142 : "r" (bit & (MALLOC_BITS-1)), "r" (pi->bits+(bit/MALLOC_BITS)));
150 op = (union overhead *)sbrk(0); 143}
151 n = n - sizeof (*op) - ((long)op & (n - 1)); 144
152 if (n < 0) 145#endif /* __i386__ */
153 n += pagesz; 146
154 if (n) { 147/*
155 if (sbrk(n) == (char *)-1) 148 * Set to one when malloc_init has been called
156 return (NULL); 149 */
157 } 150static unsigned initialized;
158 bucket = 0; 151
159 amt = 8; 152/*
160 while (pagesz > amt) { 153 * The size of a page.
161 amt <<= 1; 154 * Must be a integral multiplum of the granularity of mmap(2).
162 bucket++; 155 * Your toes will curl if it isn't a power of two
163 } 156 */
164 pagebucket = bucket; 157#ifndef malloc_pagesize
165 } 158static unsigned malloc_pagesize;
166 /* 159#endif /* malloc_pagesize */
167 * Convert amount of memory requested into closest block size 160
168 * stored in hash buckets which satisfies request. 161/*
169 * Account for space used per block for accounting. 162 * A mask for the offset inside a page.
170 */ 163 */
171 if (nbytes <= (n = pagesz - sizeof (*op) - RSLOP)) { 164#define malloc_pagemask ((malloc_pagesize)-1)
172#ifndef RCHECK 165
173 amt = 8; /* size of first bucket */ 166#define pageround(foo) (((foo) + (malloc_pagemask))&(~(malloc_pagemask)))
174 bucket = 0; 167#define ptr2index(foo) (((u_long)(foo) >> malloc_pageshift)-malloc_origo)
175#else 168
176 amt = 16; /* size of first bucket */ 169/*
177 bucket = 1; 170 * malloc_pagesize == 1 << malloc_pageshift
178#endif 171 */
179 n = -((long)sizeof (*op) + RSLOP); 172#ifndef malloc_pageshift
173static unsigned malloc_pageshift;
174#endif /* malloc_pageshift */
175
176/*
177 * The smallest allocation we bother about.
178 * Must be power of two
179 */
180#ifndef malloc_minsize
181static unsigned malloc_minsize;
182#endif /* malloc_minsize */
183
184/*
185 * The largest chunk we care about.
186 * Must be smaller than pagesize
187 * Must be power of two
188 */
189#ifndef malloc_maxsize
190static unsigned malloc_maxsize;
191#endif /* malloc_maxsize */
192
193/*
194 * The minimum size (in bytes) of the free page cache.
195 */
196#ifndef malloc_cache
197static unsigned malloc_cache;
198#endif /* malloc_cache */
199
200/*
201 * The offset from pagenumber to index into the page directory
202 */
203static u_long malloc_origo;
204
205/*
206 * The last index in the page directory we care about
207 */
208static u_long last_index;
209
210/*
211 * Pointer to page directory.
212 * Allocated "as if with" malloc
213 */
214static struct pginfo **page_dir;
215
216/*
217 * How many slots in the page directory
218 */
219static unsigned malloc_ninfo;
220
221/*
222 * Free pages line up here
223 */
224static struct pgfree free_list;
225
226/*
227 * Abort() if we fail to get VM ?
228 */
229static int malloc_abort;
230
231/*
232 * Are we trying to die ?
233 */
234static int suicide;
235
236#ifdef MALLOC_STATS
237/*
238 * dump statistics
239 */
240static int malloc_stats;
241#endif /* MALLOC_STATS */
242
243/*
244 * always realloc ?
245 */
246static int malloc_realloc;
247
248/*
249 * zero fill ?
250 */
251static int malloc_zero;
252
253/*
254 * junk fill ?
255 */
256static int malloc_junk;
257
258/*
259 * my last break.
260 */
261static void *malloc_brk;
262
263/*
264 * one location cache for free-list holders
265 */
266static struct pgfree *px;
267
268/*
269 * Necessary function declarations
270 */
271static int extend_pgdir(u_long index);
272
273#ifdef MALLOC_STATS
274void
275malloc_dump(FILE *fd)
276{
277 struct pginfo **pd;
278 struct pgfree *pf;
279 int j;
280
281 pd = page_dir;
282
283 /* print out all the pages */
284 for(j=0;j<=last_index;j++) {
285 fprintf(fd,"%08lx %5d ",(j+malloc_origo) << malloc_pageshift,j);
286 if (pd[j] == MALLOC_NOT_MINE) {
287 for(j++;j<=last_index && pd[j] == MALLOC_NOT_MINE;j++)
288 ;
289 j--;
290 fprintf(fd,".. %5d not mine\n", j);
291 } else if (pd[j] == MALLOC_FREE) {
292 for(j++;j<=last_index && pd[j] == MALLOC_FREE;j++)
293 ;
294 j--;
295 fprintf(fd,".. %5d free\n", j);
296 } else if (pd[j] == MALLOC_FIRST) {
297 for(j++;j<=last_index && pd[j] == MALLOC_FOLLOW;j++)
298 ;
299 j--;
300 fprintf(fd,".. %5d in use\n", j);
301 } else if (pd[j] < MALLOC_MAGIC) {
302 fprintf(fd,"(%p)\n", pd[j]);
180 } else { 303 } else {
181 amt = pagesz; 304 fprintf(fd,"%p %d (of %d) x %d @ %p --> %p\n",
182 bucket = pagebucket; 305 pd[j],pd[j]->free, pd[j]->total,
183 } 306 pd[j]->size, pd[j]->page, pd[j]->next);
184 while (nbytes > amt + n) {
185 amt <<= 1;
186 if (amt == 0)
187 return (NULL);
188 bucket++;
189 } 307 }
190 /* 308 }
191 * If nothing in hash bucket right now, 309
192 * request more memory from the system. 310 for(pf=free_list.next; pf; pf=pf->next) {
193 */ 311 fprintf(fd,"Free: @%p [%p...%p[ %ld ->%p <-%p\n",
194 if ((op = nextf[bucket]) == NULL) { 312 pf,pf->page,pf->end,pf->size,pf->prev,pf->next);
195 morecore(bucket); 313 if (pf == pf->next) {
196 if ((op = nextf[bucket]) == NULL) 314 fprintf(fd,"Free_list loops.\n");
197 return (NULL); 315 break;
198 } 316 }
199 /* remove from linked list */ 317 }
200 nextf[bucket] = op->ov_next; 318
201 op->ov_magic = MAGIC; 319 /* print out various info */
202 op->ov_index = bucket; 320 fprintf(fd,"Minsize\t%d\n",malloc_minsize);
203#ifdef MSTATS 321 fprintf(fd,"Maxsize\t%d\n",malloc_maxsize);
204 nmalloc[bucket]++; 322 fprintf(fd,"Pagesize\t%d\n",malloc_pagesize);
205#endif 323 fprintf(fd,"Pageshift\t%d\n",malloc_pageshift);
206#ifdef RCHECK 324 fprintf(fd,"FirstPage\t%ld\n",malloc_origo);
207 /* 325 fprintf(fd,"LastPage\t%ld %lx\n",last_index+malloc_pageshift,
208 * Record allocated size of block and 326 (last_index + malloc_pageshift) << malloc_pageshift);
209 * bound space with magic numbers. 327 fprintf(fd,"Break\t%ld\n",(u_long)sbrk(0) >> malloc_pageshift);
210 */ 328}
211 op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1); 329#endif /* MALLOC_STATS */
212 op->ov_rmagic = RMAGIC; 330
213 *(u_short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC; 331static void
214#endif 332wrterror(char *p)
215 return ((char *)(op + 1)); 333{
334 char *q = "Malloc error: ";
335 suicide = 1;
336 write(2,q,strlen(q));
337 write(2,p,strlen(p));
338#ifdef MALLOC_STATS
339 if (malloc_stats)
340 malloc_dump(stderr);
341#endif /* MALLOC_STATS */
342 abort();
343}
344
345static void
346wrtwarning(char *p)
347{
348 char *q = "Malloc warning: ";
349 if (malloc_abort)
350 wrterror(p);
351 write(2,q,strlen(q));
352 write(2,p,strlen(p));
353}
354
355#ifdef EXTRA_SANITY
356static void
357malloc_exit()
358{
359 FILE *fd = fopen("malloc.out","a");
360 char *q = "malloc() warning: Couldn't dump stats.\n";
361 if (fd) {
362 malloc_dump(fd);
363 fclose(fd);
364 } else
365 write(2,q,strlen(q));
366}
367#endif /* EXTRA_SANITY */
368
369
370/*
371 * Allocate a number of pages from the OS
372 */
373static caddr_t
374map_pages(int pages)
375{
376 caddr_t result,tail;
377
378 result = (caddr_t)pageround((u_long)sbrk(0));
379 tail = result + (pages << malloc_pageshift);
380
381 if (brk(tail)) {
382#ifdef EXTRA_SANITY
383 wrterror("(internal): map_pages fails\n");
384#endif /* EXTRA_SANITY */
385 return 0;
386 }
387
388 last_index = ptr2index(tail) - 1;
389 malloc_brk = tail;
390
391 if ((last_index+1) >= malloc_ninfo && !extend_pgdir(last_index))
392 return 0;;
393
394 return result;
395}
396
397/*
398 * Set a bit in the bitmap
399 */
400#ifndef set_bit
401static __inline void
402set_bit(struct pginfo *pi, int bit)
403{
404 pi->bits[bit/MALLOC_BITS] |= 1<<(bit%MALLOC_BITS);
405}
406#endif /* set_bit */
407
408/*
409 * Clear a bit in the bitmap
410 */
411#ifndef clr_bit
412static __inline void
413clr_bit(struct pginfo *pi, int bit)
414{
415 pi->bits[bit/MALLOC_BITS] &= ~(1<<(bit%MALLOC_BITS));
416}
417#endif /* clr_bit */
418
419#ifndef tst_bit
420/*
421 * Test a bit in the bitmap
422 */
423static __inline int
424tst_bit(struct pginfo *pi, int bit)
425{
426 return pi->bits[bit/MALLOC_BITS] & (1<<(bit%MALLOC_BITS));
427}
428#endif /* tst_bit */
429
430/*
431 * Find last bit
432 */
433#ifndef fls
434static __inline int
435fls(int size)
436{
437 int i = 1;
438 while (size >>= 1)
439 i++;
440 return i;
216} 441}
442#endif /* fls */
217 443
218/* 444/*
219 * Allocate more memory to the indicated bucket. 445 * Extend page directory
446 */
447static int
448extend_pgdir(u_long index)
449{
450 struct pginfo **new,**old;
451 int i, oldlen;
452
453 /* Make it this many pages */
454 i = index * sizeof *page_dir;
455 i /= malloc_pagesize;
456 i += 2;
457
458 /* remember the old mapping size */
459 oldlen = malloc_ninfo * sizeof *page_dir;
460
461 /*
462 * NOTE: we allocate new pages and copy the directory rather than tempt
463 * fate by trying to "grow" the region.. There is nothing to prevent
464 * us from accidently re-mapping space that's been allocated by our caller
465 * via dlopen() or other mmap().
466 *
467 * The copy problem is not too bad, as there is 4K of page index per
468 * 4MB of malloc arena.
469 *
470 * We can totally avoid the copy if we open a file descriptor to associate
471 * the anon mappings with. Then, when we remap the pages at the new
472 * address, the old pages will be "magically" remapped.. But this means
473 * keeping open a "secret" file descriptor.....
474 */
475
476 /* Get new pages */
477 new = (struct pginfo**) mmap(0, i * malloc_pagesize, PROT_READ|PROT_WRITE,
478 MAP_ANON|MAP_PRIVATE, -1, 0);
479 if (new == (struct pginfo **)-1)
480 return 0;
481
482 /* Copy the old stuff */
483 memcpy(new, page_dir,
484 malloc_ninfo * sizeof *page_dir);
485
486 /* register the new size */
487 malloc_ninfo = i * malloc_pagesize / sizeof *page_dir;
488
489 /* swap the pointers */
490 old = page_dir;
491 page_dir = new;
492
493 /* Now free the old stuff */
494 munmap((caddr_t)old, oldlen);
495 return 1;
496}
497
498/*
499 * Initialize the world
220 */ 500 */
221static void 501static void
222morecore(bucket) 502malloc_init ()
223 int bucket;
224{ 503{
225 register union overhead *op; 504 char *p;
226 register long sz; /* size of desired block */
227 long amt; /* amount to allocate */
228 int nblks; /* how many blocks we get */
229 505
230 /* 506#ifdef EXTRA_SANITY
231 * sbrk_size <= 0 only for big, FLUFFY, requests (about 507 malloc_junk = 1;
232 * 2^30 bytes on a VAX, I think) or for a negative arg. 508#endif /* EXTRA_SANITY */
233 */ 509
234 sz = 1 << (bucket + 3); 510 for (p=getenv("MALLOC_OPTIONS"); p && *p; p++) {
235#ifdef DEBUG 511 switch (*p) {
236 ASSERT(sz > 0); 512 case 'a': malloc_abort = 0; break;
237#else 513 case 'A': malloc_abort = 1; break;
238 if (sz <= 0) 514#ifdef MALLOC_STATS
239 return; 515 case 'd': malloc_stats = 0; break;
240#endif 516 case 'D': malloc_stats = 1; break;
241 if (sz < pagesz) { 517#endif /* MALLOC_STATS */
242 amt = pagesz; 518 case 'r': malloc_realloc = 0; break;
243 nblks = amt / sz; 519 case 'R': malloc_realloc = 1; break;
244 } else { 520 case 'j': malloc_junk = 0; break;
245 amt = sz + pagesz; 521 case 'J': malloc_junk = 1; break;
246 nblks = 1; 522 case 'z': malloc_zero = 0; break;
523 case 'Z': malloc_zero = 1; break;
524 default:
525 wrtwarning("(Init): Unknown char in MALLOC_OPTIONS\n");
526 p = 0;
527 break;
247 } 528 }
248 op = (union overhead *)sbrk(amt); 529 }
249 /* no more room! */ 530
250 if ((long)op == -1) 531 /*
251 return; 532 * We want junk in the entire allocation, and zero only in the part
252 /* 533 * the user asked for.
253 * Add new memory allocated to that on 534 */
254 * free list for this hash bucket. 535 if (malloc_zero)
255 */ 536 malloc_junk=1;
256 nextf[bucket] = op; 537
257 while (--nblks > 0) { 538#ifdef EXTRA_SANITY
258 op->ov_next = (union overhead *)((caddr_t)op + sz); 539 if (malloc_stats)
259 op = (union overhead *)((caddr_t)op + sz); 540 atexit(malloc_exit);
260 } 541#endif /* EXTRA_SANITY */
542
543#ifndef malloc_pagesize
544 /* determine our pagesize */
545 malloc_pagesize = getpagesize();
546#endif /* malloc_pagesize */
547
548#ifndef malloc_maxsize
549 malloc_maxsize = malloc_pagesize >> 1;
550#endif /* malloc_maxsize */
551
552#ifndef malloc_pageshift
553 {
554 int i;
555 /* determine how much we shift by to get there */
556 for (i = malloc_pagesize; i > 1; i >>= 1)
557 malloc_pageshift++;
558 }
559#endif /* malloc_pageshift */
560
561#ifndef malloc_cache
562 malloc_cache = 100 << malloc_pageshift;
563#endif /* malloc_cache */
564
565#ifndef malloc_minsize
566 {
567 int i;
568 /*
569 * find the smallest size allocation we will bother about.
570 * this is determined as the smallest allocation that can hold
571 * it's own pginfo;
572 */
573 i = 2;
574 for(;;) {
575 int j;
576
577 /* Figure out the size of the bits */
578 j = malloc_pagesize/i;
579 j /= 8;
580 if (j < sizeof(u_long))
581 j = sizeof (u_long);
582 if (sizeof(struct pginfo) + j - sizeof (u_long) <= i)
583 break;
584 i += i;
585 }
586 malloc_minsize = i;
587 }
588#endif /* malloc_minsize */
589
590 /* Allocate one page for the page directory */
591 page_dir = (struct pginfo **) mmap(0, malloc_pagesize, PROT_READ|PROT_WRITE,
592 MAP_ANON|MAP_PRIVATE, -1, 0);
593 if (page_dir == (struct pginfo **) -1)
594 wrterror("(Init) my first mmap failed. (check limits ?)\n");
595
596 /*
597 * We need a maximum of malloc_pageshift buckets, steal these from the
598 * front of the page_directory;
599 */
600 malloc_origo = ((u_long)pageround((u_long)sbrk(0))) >> malloc_pageshift;
601 malloc_origo -= malloc_pageshift;
602
603 malloc_ninfo = malloc_pagesize / sizeof *page_dir;
604
605 /* Been here, done that */
606 initialized++;
607
608 /*
609 * This is a nice hack from Kaleb Keithly (kaleb@x.org).
610 * We can sbrk(2) further back when we keep this on a low address.
611 */
612 px = (struct pgfree *) malloc (sizeof *px);
261} 613}
262 614
263void 615/*
264free(cp) 616 * Allocate a number of complete pages
265 void *cp; 617 */
266{ 618void *
267 register long size; 619malloc_pages(size_t size)
268 register union overhead *op; 620{
269 621 void *p,*delay_free = 0;
270 if (cp == NULL) 622 int i;
271 return; 623 struct pgfree *pf;
272 op = (union overhead *)((caddr_t)cp - sizeof (union overhead)); 624 u_long index;
273#ifdef DEBUG 625
274 ASSERT(op->ov_magic == MAGIC); /* make sure it was in use */ 626 size = pageround(size);
275#else 627
276 if (op->ov_magic != MAGIC) 628 p = 0;
277 return; /* sanity */ 629 /* Look for free pages before asking for more */
630 for(pf = free_list.next; pf; pf = pf->next) {
631
632#ifdef EXTRA_SANITY
633 if (pf->size & malloc_pagemask)
634 wrterror("(ES): junk length entry on free_list\n");
635 if (!pf->size)
636 wrterror("(ES): zero length entry on free_list\n");
637 if (pf->page == pf->end)
638 wrterror("(ES): zero entry on free_list\n");
639 if (pf->page > pf->end)
640 wrterror("(ES): sick entry on free_list\n");
641 if ((void*)pf->page >= (void*)sbrk(0))
642 wrterror("(ES): entry on free_list past brk\n");
643 if (page_dir[ptr2index(pf->page)] != MALLOC_FREE)
644 wrterror("(ES): non-free first page on free-list\n");
645 if (page_dir[ptr2index(pf->end)-1] != MALLOC_FREE)
646 wrterror("(ES): non-free last page on free-list\n");
647#endif /* EXTRA_SANITY */
648
649 if (pf->size < size)
650 continue;
651
652 if (pf->size == size) {
653 p = pf->page;
654 if (pf->next)
655 pf->next->prev = pf->prev;
656 pf->prev->next = pf->next;
657 delay_free = pf;
658 break;
659 }
660
661 p = pf->page;
662 pf->page += size;
663 pf->size -= size;
664 break;
665 }
666
667#ifdef EXTRA_SANITY
668 if (p && page_dir[ptr2index(p)] != MALLOC_FREE)
669 wrterror("(ES): allocated non-free page on free-list\n");
670#endif /* EXTRA_SANITY */
671
672 size >>= malloc_pageshift;
673
674 /* Map new pages */
675 if (!p)
676 p = map_pages(size);
677
678 if (p) {
679
680 index = ptr2index(p);
681 page_dir[index] = MALLOC_FIRST;
682 for (i=1;i<size;i++)
683 page_dir[index+i] = MALLOC_FOLLOW;
684
685 if (malloc_junk)
686 memset(p, SOME_JUNK,size << malloc_pageshift);
687 }
688
689 if (delay_free) {
690 if (!px)
691 px = delay_free;
692 else
693 free(delay_free);
694 }
695
696 return p;
697}
698
699/*
700 * Allocate a page of fragments
701 */
702
703static __inline int
704malloc_make_chunks(int bits)
705{
706 struct pginfo *bp;
707 void *pp;
708 int i,k,l;
709
710 /* Allocate a new bucket */
711 pp = malloc_pages(malloc_pagesize);
712 if (!pp)
713 return 0;
714
715 /* Find length of admin structure */
716 l = sizeof *bp - sizeof(u_long);
717 l += sizeof(u_long) *
718 (((malloc_pagesize >> bits)+MALLOC_BITS-1) / MALLOC_BITS);
719
720 /* Don't waste more than two chunks on this */
721 if ((1<<(bits)) <= l+l) {
722 bp = (struct pginfo *)pp;
723 } else {
724 bp = (struct pginfo *)malloc(l);
725 if (!bp)
726 return 0;
727 }
728
729 bp->size = (1<<bits);
730 bp->shift = bits;
731 bp->total = bp->free = malloc_pagesize >> bits;
732 bp->page = pp;
733
734 page_dir[ptr2index(pp)] = bp;
735
736 bp->next = page_dir[bits];
737 page_dir[bits] = bp;
738
739 /* set all valid bits in the bits */
740 k = bp->total;
741 i = 0;
742
743 /* Do a bunch at a time */
744 for(;k-i >= MALLOC_BITS; i += MALLOC_BITS)
745 bp->bits[i / MALLOC_BITS] = ~0;
746
747 for(; i < k; i++)
748 set_bit(bp,i);
749
750 if (bp == bp->page) {
751 /* Mark the ones we stole for ourselves */
752 for(i=0;l > 0;i++) {
753 clr_bit(bp,i);
754 bp->free--;
755 bp->total--;
756 l -= (1 << bits);
757 }
758 }
759
760 return 1;
761}
762
763/*
764 * Allocate a fragment
765 */
766static void *
767malloc_bytes(size_t size)
768{
769 int j;
770 struct pginfo *bp;
771 int k;
772 u_long *lp;
773
774 /* Don't bother with anything less than this */
775 if (size < malloc_minsize)
776 size = malloc_minsize;
777
778 /* Find the right bucket */
779 j = fls((size)-1);
780
781 /* If it's empty, make a page more of that size chunks */
782 if (!page_dir[j] && !malloc_make_chunks(j))
783 return 0;
784
785 bp = page_dir[j];
786
787 /* Find first word of bitmap which isn't empty */
788 for (lp = bp->bits; !*lp; lp++)
789 ;
790
791 /* Find that bit, and tweak it */
792 k = ffs(*lp) - 1;
793 *lp ^= 1<<k;
794
795 /* If there are no more free, remove from free-list */
796 if (!--bp->free) {
797 page_dir[j] = bp->next;
798 bp->next = 0;
799 }
800
801 /* Adjust to the real offset of that chunk */
802 k += (lp-bp->bits)*MALLOC_BITS;
803 k <<= bp->shift;
804
805 if (malloc_junk)
806 memset(bp->page + k, SOME_JUNK, bp->size);
807
808 return bp->page + k;
809}
810
811/*
812 * Allocate a piece of memory
813 */
814void *
815malloc(size_t size)
816{
817 void *result;
818#ifdef _THREAD_SAFE
819 int status;
278#endif 820#endif
279#ifdef RCHECK 821
280 ASSERT(op->ov_rmagic == RMAGIC); 822 if (!initialized)
281 ASSERT(*(u_short *)((caddr_t)(op + 1) + op->ov_size) == RMAGIC); 823 malloc_init();
824
825 if (suicide)
826 abort();
827
828#ifdef _THREAD_SAFE
829 _thread_kern_sig_block(&status);
282#endif 830#endif
283 size = op->ov_index; 831 if (size <= malloc_maxsize)
284 ASSERT(size < NBUCKETS); 832 result = malloc_bytes(size);
285 op->ov_next = nextf[size]; /* also clobbers ov_magic */ 833 else
286 nextf[size] = op; 834 result = malloc_pages(size);
287#ifdef MSTATS 835
288 nmalloc[size]--; 836 if (malloc_abort && !result)
837 wrterror("malloc(): returns NULL\n");
838
839 if (malloc_zero)
840 memset(result,0,size);
841
842#ifdef _THREAD_SAFE
843 _thread_kern_sig_unblock(status);
289#endif 844#endif
845 return result;
290} 846}
291 847
292/* 848/*
293 * When a program attempts "storage compaction" as mentioned in the 849 * Change the size of an allocation.
294 * old malloc man page, it realloc's an already freed block. Usually
295 * this is the last block it freed; occasionally it might be farther
296 * back. We have to search all the free lists for the block in order
297 * to determine its bucket: 1st we make one pass thru the lists
298 * checking only the first block in each; if that fails we search
299 * ``realloc_srchlen'' blocks in each list for a match (the variable
300 * is extern so the caller can modify it). If that fails we just copy
301 * however many bytes was given to realloc() and hope it's not huge.
302 */ 850 */
303int realloc_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */
304
305void * 851void *
306realloc(cp, nbytes) 852realloc(void *ptr, size_t size)
307 void *cp; 853{
308 size_t nbytes; 854 void *p;
309{ 855 u_long osize,index;
310 register u_long onb; 856 struct pginfo **mp;
311 register long i; 857 int i;
312 union overhead *op; 858#ifdef _THREAD_SAFE
313 char *res; 859 int status;
314 int was_alloced = 0; 860#endif
315 861
316 if (cp == NULL) 862 if (suicide)
317 return (malloc(nbytes)); 863 return 0;
318 if (nbytes == 0) { 864
319 free (cp); 865 if (!ptr) /* Bounce to malloc() */
320 return NULL; 866 return malloc(size);
867
868 if (!initialized) {
869 wrtwarning("realloc(): malloc() never got called.\n");
870 return 0;
871 }
872
873 if (ptr && !size) { /* Bounce to free() */
874 free(ptr);
875 return 0;
876 }
877
878#ifdef _THREAD_SAFE
879 _thread_kern_sig_block(&status);
880#endif
881 index = ptr2index(ptr);
882
883 if (index < malloc_pageshift) {
884 wrtwarning("realloc(): junk pointer (too low)\n");
885#ifdef _THREAD_SAFE
886 _thread_kern_sig_unblock(status);
887#endif
888 return 0;
889 }
890
891 if (index > last_index) {
892 wrtwarning("realloc(): junk pointer (too high)\n");
893#ifdef _THREAD_SAFE
894 _thread_kern_sig_unblock(status);
895#endif
896 return 0;
897 }
898
899 mp = &page_dir[index];
900
901 if (*mp == MALLOC_FIRST) { /* Page allocation */
902
903 /* Check the pointer */
904 if ((u_long)ptr & malloc_pagemask) {
905 wrtwarning("realloc(): modified page pointer.\n");
906#ifdef _THREAD_SAFE
907 _thread_kern_sig_unblock(status);
908#endif
909 return 0;
321 } 910 }
322 op = (union overhead *)((caddr_t)cp - sizeof (union overhead)); 911
323 if (op->ov_magic == MAGIC) { 912 /* Find the size in bytes */
324 was_alloced++; 913 for (osize = malloc_pagesize; *++mp == MALLOC_FOLLOW;)
325 i = op->ov_index; 914 osize += malloc_pagesize;
326 } else { 915
327 /* 916 if (!malloc_realloc && /* unless we have to, */
328 * Already free, doing "compaction". 917 size <= osize && /* .. or are too small, */
329 * 918 size > (osize - malloc_pagesize)) { /* .. or can free a page, */
330 * Search for the old block of memory on the 919#ifdef _THREAD_SAFE
331 * free list. First, check the most common 920 _thread_kern_sig_unblock(status);
332 * case (last element free'd), then (this failing) 921#endif
333 * the last ``realloc_srchlen'' items free'd. 922 return ptr; /* don't do anything. */
334 * If all lookups fail, then assume the size of
335 * the memory block being realloc'd is the
336 * largest possible (so that all "nbytes" of new
337 * memory are copied into). Note that this could cause
338 * a memory fault if the old area was tiny, and the moon
339 * is gibbous. However, that is very unlikely.
340 */
341 if ((i = findbucket(op, 1)) < 0 &&
342 (i = findbucket(op, realloc_srchlen)) < 0)
343 i = NBUCKETS;
344 } 923 }
345 onb = 1 << (i + 3); 924
346 if (onb < pagesz) 925 } else if (*mp >= MALLOC_MAGIC) { /* Chunk allocation */
347 onb -= sizeof (*op) + RSLOP; 926
348 else 927 /* Check the pointer for sane values */
349 onb += pagesz - sizeof (*op) - RSLOP; 928 if (((u_long)ptr & ((*mp)->size-1))) {
350 /* avoid the copy if same size block */ 929 wrtwarning("realloc(): modified chunk pointer.\n");
351 if (was_alloced) { 930#ifdef _THREAD_SAFE
352 if (i) { 931 _thread_kern_sig_unblock(status);
353 i = 1 << (i + 2); 932#endif
354 if (i < pagesz) 933 return 0;
355 i -= sizeof (*op) + RSLOP; 934 }
356 else 935
357 i += pagesz - sizeof (*op) - RSLOP; 936 /* Find the chunk index in the page */
358 } 937 i = ((u_long)ptr & malloc_pagemask) >> (*mp)->shift;
359 if (nbytes <= onb && nbytes > i) { 938
360#ifdef RCHECK 939 /* Verify that it isn't a free chunk already */
361 op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1); 940 if (tst_bit(*mp,i)) {
362 *(u_short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC; 941 wrtwarning("realloc(): already free chunk.\n");
942#ifdef _THREAD_SAFE
943 _thread_kern_sig_unblock(status);
944#endif
945 return 0;
946 }
947
948 osize = (*mp)->size;
949
950 if (!malloc_realloc && /* Unless we have to, */
951 size < osize && /* ..or are too small, */
952 (size > osize/2 || /* ..or could use a smaller size, */
953 osize == malloc_minsize)) { /* ..(if there is one) */
954#ifdef _THREAD_SAFE
955 _thread_kern_sig_unblock(status);
363#endif 956#endif
364 return(cp); 957 return ptr; /* ..Don't do anything */
365 } else
366 free(cp);
367 } 958 }
368 if ((res = malloc(nbytes)) == NULL) 959
369 return (NULL); 960 } else {
370 if (cp != res) /* common optimization if "compacting" */ 961 wrtwarning("realloc(): wrong page pointer.\n");
371 bcopy(cp, res, (nbytes < onb) ? nbytes : onb); 962#ifdef _THREAD_SAFE
372 return (res); 963 _thread_kern_sig_unblock(status);
964#endif
965 return 0;
966 }
967
968 p = malloc(size);
969
970 if (p) {
971 /* copy the lesser of the two sizes, and free the old one */
972 if (osize < size)
973 memcpy(p,ptr,osize);
974 else
975 memcpy(p,ptr,size);
976 free(ptr);
977 }
978#ifdef _THREAD_SAFE
979 _thread_kern_sig_unblock(status);
980#endif
981 return p;
373} 982}
374 983
375/* 984/*
376 * Search ``srchlen'' elements of each free list for a block whose 985 * Free a sequence of pages
377 * header starts at ``freep''. If srchlen is -1 search the whole list.
378 * Return bucket number, or -1 if not found.
379 */ 986 */
380static 987
381findbucket(freep, srchlen) 988static __inline void
382 union overhead *freep; 989free_pages(void *ptr, int index, struct pginfo *info)
383 int srchlen;
384{ 990{
385 register union overhead *p; 991 int i;
386 register int i, j; 992 struct pgfree *pf,*pt;
387 993 u_long l;
388 for (i = 0; i < NBUCKETS; i++) { 994 void *tail;
389 j = 0; 995
390 for (p = nextf[i]; p && j != srchlen; p = p->ov_next) { 996 if (info == MALLOC_FREE) {
391 if (p == freep) 997 wrtwarning("free(): already free page.\n");
392 return (i); 998 return;
393 j++; 999 }
394 } 1000
1001 if (info != MALLOC_FIRST) {
1002 wrtwarning("free(): freeing wrong page.\n");
1003 return;
1004 }
1005
1006 if ((u_long)ptr & malloc_pagemask) {
1007 wrtwarning("free(): modified page pointer.\n");
1008 return;
1009 }
1010
1011 /* Count how many pages and mark them free at the same time */
1012 page_dir[index] = MALLOC_FREE;
1013 for (i = 1; page_dir[index+i] == MALLOC_FOLLOW; i++)
1014 page_dir[index + i] = MALLOC_FREE;
1015
1016 l = i << malloc_pageshift;
1017
1018 tail = ptr+l;
1019
1020 /* add to free-list */
1021 if (!px)
1022 px = malloc(sizeof *pt); /* This cannot fail... */
1023 px->page = ptr;
1024 px->end = tail;
1025 px->size = l;
1026 if (!free_list.next) {
1027
1028 /* Nothing on free list, put this at head */
1029 px->next = free_list.next;
1030 px->prev = &free_list;
1031 free_list.next = px;
1032 pf = px;
1033 px = 0;
1034
1035 } else {
1036
1037 /* Find the right spot, leave pf pointing to the modified entry. */
1038 tail = ptr+l;
1039
1040 for(pf = free_list.next; pf->end < ptr && pf->next; pf = pf->next)
1041 ; /* Race ahead here */
1042
1043 if (pf->page > tail) {
1044 /* Insert before entry */
1045 px->next = pf;
1046 px->prev = pf->prev;
1047 pf->prev = px;
1048 px->prev->next = px;
1049 pf = px;
1050 px = 0;
1051 } else if (pf->end == ptr ) {
1052 /* Append to the previous entry */
1053 pf->end += l;
1054 pf->size += l;
1055 if (pf->next && pf->end == pf->next->page ) {
1056 /* And collapse the next too. */
1057 pt = pf->next;
1058 pf->end = pt->end;
1059 pf->size += pt->size;
1060 pf->next = pt->next;
1061 if (pf->next)
1062 pf->next->prev = pf;
1063 free(pt);
1064 }
1065 } else if (pf->page == tail) {
1066 /* Prepend to entry */
1067 pf->size += l;
1068 pf->page = ptr;
1069 } else if (!pf->next) {
1070 /* Append at tail of chain */
1071 px->next = 0;
1072 px->prev = pf;
1073 pf->next = px;
1074 pf = px;
1075 px = 0;
1076 } else {
1077 wrterror("messed up free list");
395 } 1078 }
396 return (-1); 1079 }
1080
1081 /* Return something to OS ? */
1082 if (!pf->next && /* If we're the last one, */
1083 pf->size > malloc_cache && /* ..and the cache is full, */
1084 pf->end == malloc_brk && /* ..and none behind us, */
1085 malloc_brk == sbrk(0)) { /* ..and it's OK to do... */
1086
1087 /*
1088 * Keep the cache intact. Notice that the '>' above guarantees that
1089 * the pf will always have at least one page afterwards.
1090 */
1091 pf->end = pf->page + malloc_cache;
1092 pf->size = malloc_cache;
1093
1094 brk(pf->end);
1095 malloc_brk = pf->end;
1096
1097 index = ptr2index(pf->end);
1098 last_index = index - 1;
1099
1100 for(i=index;i <= last_index;)
1101 page_dir[i++] = MALLOC_NOT_MINE;
1102
1103 /* XXX: We could realloc/shrink the pagedir here I guess. */
1104 }
397} 1105}
398 1106
399#ifdef MSTATS
400/* 1107/*
401 * mstats - print out statistics about malloc 1108 * Free a chunk, and possibly the page it's on, if the page becomes empty.
402 *
403 * Prints two lines of numbers, one showing the length of the free list
404 * for each size category, the second showing the number of mallocs -
405 * frees for each size category.
406 */ 1109 */
407mstats(s) 1110
408 char *s; 1111static __inline void
1112free_bytes(void *ptr, int index, struct pginfo *info)
409{ 1113{
410 register int i, j; 1114 int i;
411 register union overhead *p; 1115 struct pginfo **mp;
412 int totfree = 0, 1116 void *vp;
413 totused = 0; 1117
414 1118 /* Find the chunk number on the page */
415 fprintf(stderr, "Memory allocation statistics %s\nfree:\t", s); 1119 i = ((u_long)ptr & malloc_pagemask) >> info->shift;
416 for (i = 0; i < NBUCKETS; i++) { 1120
417 for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) 1121 if (((u_long)ptr & (info->size-1))) {
418 ; 1122 wrtwarning("free(): modified pointer.\n");
419 fprintf(stderr, " %d", j); 1123 return;
420 totfree += j * (1 << (i + 3)); 1124 }
421 } 1125
422 fprintf(stderr, "\nused:\t"); 1126 if (tst_bit(info,i)) {
423 for (i = 0; i < NBUCKETS; i++) { 1127 wrtwarning("free(): already free chunk.\n");
424 fprintf(stderr, " %d", nmalloc[i]); 1128 return;
425 totused += nmalloc[i] * (1 << (i + 3)); 1129 }
426 } 1130
427 fprintf(stderr, "\n\tTotal in use: %d, total free: %d\n", 1131 set_bit(info,i);
428 totused, totfree); 1132 info->free++;
1133
1134 mp = page_dir + info->shift;
1135
1136 if (info->free == 1) {
1137
1138 /* Page became non-full */
1139
1140 mp = page_dir + info->shift;
1141 /* Insert in address order */
1142 while (*mp && (*mp)->next && (*mp)->next->page < info->page)
1143 mp = &(*mp)->next;
1144 info->next = *mp;
1145 *mp = info;
1146 return;
1147 }
1148
1149 if (info->free != info->total)
1150 return;
1151
1152 /* Find & remove this page in the queue */
1153 while (*mp != info) {
1154 mp = &((*mp)->next);
1155#ifdef EXTRA_SANITY
1156 if (!*mp)
1157 wrterror("(ES): Not on queue\n");
1158#endif /* EXTRA_SANITY */
1159 }
1160 *mp = info->next;
1161
1162 /* Free the page & the info structure if need be */
1163 page_dir[ptr2index(info->page)] = MALLOC_FIRST;
1164 vp = info->page; /* Order is important ! */
1165 if(vp != (void*)info)
1166 free(info);
1167 free(vp);
429} 1168}
1169
1170void
1171free(void *ptr)
1172{
1173 struct pginfo *info;
1174 int index;
1175#ifdef _THREAD_SAFE
1176 int status;
1177#endif
1178
1179 /* This is legal */
1180 if (!ptr)
1181 return;
1182
1183 if (!initialized) {
1184 wrtwarning("free(): malloc() never got called.\n");
1185 return;
1186 }
1187
1188 /* If we're already sinking, don't make matters any worse. */
1189 if (suicide)
1190 return;
1191
1192#ifdef _THREAD_SAFE
1193 _thread_kern_sig_block(&status);
430#endif 1194#endif
1195 index = ptr2index(ptr);
1196
1197 if (index < malloc_pageshift) {
1198 wrtwarning("free(): junk pointer (too low)\n");
1199#ifdef _THREAD_SAFE
1200 _thread_kern_sig_unblock(status);
1201#endif
1202 return;
1203 }
1204
1205 if (index > last_index) {
1206 wrtwarning("free(): junk pointer (too high)\n");
1207#ifdef _THREAD_SAFE
1208 _thread_kern_sig_unblock(status);
1209#endif
1210 return;
1211 }
1212
1213 info = page_dir[index];
1214
1215 if (info < MALLOC_MAGIC)
1216 free_pages(ptr,index,info);
1217 else
1218 free_bytes(ptr,index,info);
1219#ifdef _THREAD_SAFE
1220 _thread_kern_sig_unblock(status);
1221#endif
1222 return;
1223}
generated by cgit v1.2.3-55-g6feb (git 2.39.1) at 2025-03-26 01:00:44 +0000