malloc.c revision 1.20 1 1.20 thorpej /* $NetBSD: malloc.c,v 1.20 1999/07/05 21:49:05 thorpej Exp $ */
2 1.18 thorpej
3 1.1 cgd /*
4 1.17 tls * ----------------------------------------------------------------------------
5 1.17 tls * "THE BEER-WARE LICENSE" (Revision 42):
6 1.17 tls * <phk (at) FreeBSD.ORG> wrote this file. As long as you retain this notice you
7 1.17 tls * can do whatever you want with this stuff. If we meet some day, and you think
8 1.17 tls * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
9 1.17 tls * ----------------------------------------------------------------------------
10 1.1 cgd *
11 1.17 tls * From FreeBSD: malloc.c,v 1.43 1998/09/30 06:13:59 jb
12 1.1 cgd *
13 1.17 tls */
14 1.17 tls
15 1.17 tls /*
16 1.19 thorpej * Defining MALLOC_EXTRA_SANITY will enable extra checks which are related
17 1.17 tls * to internal conditions and consistency in malloc.c. This has a
18 1.17 tls * noticeable runtime performance hit, and generally will not do you
19 1.17 tls * any good unless you fiddle with the internals of malloc or want
20 1.17 tls * to catch random pointer corruption as early as possible.
21 1.17 tls */
22 1.17 tls #ifndef MALLOC_EXTRA_SANITY
23 1.17 tls #undef MALLOC_EXTRA_SANITY
24 1.5 thorpej #endif
25 1.1 cgd
26 1.1 cgd /*
27 1.17 tls * What to use for Junk. This is the byte value we use to fill with
28 1.17 tls * when the 'J' option is enabled.
29 1.17 tls */
30 1.17 tls #define SOME_JUNK 0xd0 /* as in "Duh" :-) */
31 1.17 tls
32 1.17 tls /*
33 1.17 tls * The basic parameters you can tweak.
34 1.17 tls *
35 1.17 tls * malloc_minsize minimum size of an allocation in bytes.
36 1.17 tls * If this is too small it's too much work
37 1.17 tls * to manage them. This is also the smallest
38 1.17 tls * unit of alignment used for the storage
39 1.17 tls * returned by malloc/realloc.
40 1.1 cgd *
41 1.1 cgd */
42 1.1 cgd
43 1.17 tls #if defined(__FreeBSD__)
44 1.17 tls # if defined(__i386__)
45 1.17 tls # define malloc_minsize 16U
46 1.17 tls # endif
47 1.17 tls # if defined(__alpha__)
48 1.17 tls # define malloc_minsize 16U
49 1.17 tls # endif
50 1.17 tls # if !defined(__NETBSD_SYSCALLS)
51 1.17 tls # define HAS_UTRACE
52 1.17 tls # endif
53 1.17 tls /*
54 1.17 tls * Make malloc/free/realloc thread-safe in libc for use with
55 1.17 tls * kernel threads.
56 1.17 tls */
57 1.17 tls # include "libc_private.h"
58 1.17 tls # include "spinlock.h"
59 1.17 tls static spinlock_t thread_lock = _SPINLOCK_INITIALIZER;
60 1.17 tls # define THREAD_LOCK() if (__isthreaded) _SPINLOCK(&thread_lock);
61 1.17 tls # define THREAD_UNLOCK() if (__isthreaded) _SPINUNLOCK(&thread_lock);
62 1.17 tls #endif /* __FreeBSD__ */
63 1.17 tls
64 1.17 tls #if defined(__NetBSD__)
65 1.17 tls # define malloc_minsize 16U
66 1.17 tls #endif /* __NetBSD__ */
67 1.17 tls
68 1.17 tls #if defined(__sparc__) && defined(sun)
69 1.17 tls # define malloc_minsize 16U
70 1.17 tls # define MAP_ANON (0)
71 1.17 tls static int fdzero;
72 1.17 tls # define MMAP_FD fdzero
73 1.17 tls # define INIT_MMAP() \
74 1.17 tls { if ((fdzero=open("/dev/zero", O_RDWR, 0000)) == -1) \
75 1.17 tls wrterror("open of /dev/zero"); }
76 1.17 tls #endif /* __sparc__ */
77 1.17 tls
78 1.17 tls /* Insert your combination here... */
79 1.17 tls #if defined(__FOOCPU__) && defined(__BAROS__)
80 1.17 tls # define malloc_minsize 16U
81 1.17 tls #endif /* __FOOCPU__ && __BAROS__ */
82 1.17 tls
83 1.17 tls
84 1.17 tls /*
85 1.17 tls * No user serviceable parts behind this point.
86 1.17 tls */
87 1.16 kleink #include <sys/types.h>
88 1.17 tls #include <sys/mman.h>
89 1.17 tls #include <errno.h>
90 1.17 tls #include <fcntl.h>
91 1.17 tls #include <stddef.h>
92 1.9 christos #include <stdio.h>
93 1.1 cgd #include <stdlib.h>
94 1.1 cgd #include <string.h>
95 1.1 cgd #include <unistd.h>
96 1.1 cgd
97 1.17 tls /*
98 1.17 tls * This structure describes a page worth of chunks.
99 1.17 tls */
100 1.17 tls
101 1.17 tls struct pginfo {
102 1.17 tls struct pginfo *next; /* next on the free list */
103 1.17 tls void *page; /* Pointer to the page */
104 1.17 tls u_short size; /* size of this page's chunks */
105 1.17 tls u_short shift; /* How far to shift for this size chunks */
106 1.17 tls u_short free; /* How many free chunks */
107 1.17 tls u_short total; /* How many chunk */
108 1.17 tls u_int bits[1]; /* Which chunks are free */
109 1.17 tls };
110 1.1 cgd
111 1.1 cgd /*
112 1.17 tls * This structure describes a number of free pages.
113 1.17 tls */
114 1.17 tls
115 1.17 tls struct pgfree {
116 1.17 tls struct pgfree *next; /* next run of free pages */
117 1.17 tls struct pgfree *prev; /* prev run of free pages */
118 1.17 tls void *page; /* pointer to free pages */
119 1.17 tls void *end; /* pointer to end of free pages */
120 1.17 tls size_t size; /* number of bytes free */
121 1.1 cgd };
122 1.1 cgd
123 1.17 tls /*
124 1.17 tls * How many bits per u_int in the bitmap.
125 1.17 tls * Change only if not 8 bits/byte
126 1.17 tls */
127 1.17 tls #define MALLOC_BITS (8*sizeof(u_int))
128 1.17 tls
129 1.17 tls /*
130 1.17 tls * Magic values to put in the page_directory
131 1.17 tls */
132 1.17 tls #define MALLOC_NOT_MINE ((struct pginfo*) 0)
133 1.17 tls #define MALLOC_FREE ((struct pginfo*) 1)
134 1.17 tls #define MALLOC_FIRST ((struct pginfo*) 2)
135 1.17 tls #define MALLOC_FOLLOW ((struct pginfo*) 3)
136 1.17 tls #define MALLOC_MAGIC ((struct pginfo*) 4)
137 1.17 tls
138 1.20 thorpej /*
139 1.20 thorpej * Page size related parameters, computed at run-time.
140 1.20 thorpej */
141 1.20 thorpej static size_t malloc_pagesize;
142 1.20 thorpej static size_t malloc_pageshift;
143 1.20 thorpej static size_t malloc_pagemask;
144 1.17 tls
145 1.17 tls #ifndef malloc_minsize
146 1.17 tls #define malloc_minsize 16U
147 1.17 tls #endif
148 1.17 tls
149 1.17 tls #ifndef malloc_maxsize
150 1.17 tls #define malloc_maxsize ((malloc_pagesize)>>1)
151 1.17 tls #endif
152 1.17 tls
153 1.17 tls #define pageround(foo) (((foo) + (malloc_pagemask))&(~(malloc_pagemask)))
154 1.17 tls #define ptr2index(foo) (((u_long)(foo) >> malloc_pageshift)-malloc_origo)
155 1.1 cgd
156 1.17 tls #ifndef THREAD_LOCK
157 1.17 tls #define THREAD_LOCK()
158 1.17 tls #endif
159 1.1 cgd
160 1.17 tls #ifndef THREAD_UNLOCK
161 1.17 tls #define THREAD_UNLOCK()
162 1.16 kleink #endif
163 1.16 kleink
164 1.17 tls #ifndef MMAP_FD
165 1.17 tls #define MMAP_FD (-1)
166 1.1 cgd #endif
167 1.1 cgd
168 1.17 tls #ifndef INIT_MMAP
169 1.17 tls #define INIT_MMAP()
170 1.18 thorpej #endif
171 1.18 thorpej
172 1.18 thorpej #ifndef MADV_FREE
173 1.18 thorpej #define MADV_FREE MADV_DONTNEED
174 1.9 christos #endif
175 1.9 christos
176 1.17 tls /* Set when initialization has been done */
177 1.17 tls static unsigned malloc_started;
178 1.17 tls
179 1.17 tls /* Recusion flag for public interface. */
180 1.17 tls static int malloc_active;
181 1.17 tls
182 1.17 tls /* Number of free pages we cache */
183 1.17 tls static unsigned malloc_cache = 16;
184 1.17 tls
185 1.17 tls /* The offset from pagenumber to index into the page directory */
186 1.17 tls static u_long malloc_origo;
187 1.17 tls
188 1.17 tls /* The last index in the page directory we care about */
189 1.17 tls static u_long last_index;
190 1.17 tls
191 1.17 tls /* Pointer to page directory. Allocated "as if with" malloc */
192 1.17 tls static struct pginfo **page_dir;
193 1.17 tls
194 1.17 tls /* How many slots in the page directory */
195 1.17 tls static unsigned malloc_ninfo;
196 1.17 tls
197 1.17 tls /* Free pages line up here */
198 1.17 tls static struct pgfree free_list;
199 1.17 tls
200 1.17 tls /* Abort(), user doesn't handle problems. */
201 1.17 tls static int malloc_abort;
202 1.17 tls
203 1.17 tls /* Are we trying to die ? */
204 1.17 tls static int suicide;
205 1.17 tls
206 1.17 tls /* always realloc ? */
207 1.17 tls static int malloc_realloc;
208 1.9 christos
209 1.17 tls /* pass the kernel a hint on free pages ? */
210 1.17 tls static int malloc_hint = 1;
211 1.17 tls
212 1.17 tls /* xmalloc behaviour ? */
213 1.17 tls static int malloc_xmalloc;
214 1.17 tls
215 1.17 tls /* sysv behaviour for malloc(0) ? */
216 1.17 tls static int malloc_sysv;
217 1.17 tls
218 1.17 tls /* zero fill ? */
219 1.17 tls static int malloc_zero;
220 1.17 tls
221 1.17 tls /* junk fill ? */
222 1.17 tls static int malloc_junk;
223 1.17 tls
224 1.17 tls #ifdef HAS_UTRACE
225 1.17 tls
226 1.17 tls /* utrace ? */
227 1.17 tls static int malloc_utrace;
228 1.17 tls
229 1.17 tls struct ut { void *p; size_t s; void *r; };
230 1.17 tls
231 1.17 tls void utrace __P((struct ut *, int));
232 1.17 tls
233 1.17 tls #define UTRACE(a, b, c) \
234 1.17 tls if (malloc_utrace) \
235 1.17 tls {struct ut u; u.p=a; u.s = b; u.r=c; utrace(&u, sizeof u);}
236 1.17 tls #else /* !HAS_UTRACE */
237 1.17 tls #define UTRACE(a,b,c)
238 1.17 tls #endif /* HAS_UTRACE */
239 1.17 tls
240 1.17 tls /* my last break. */
241 1.17 tls static void *malloc_brk;
242 1.17 tls
243 1.17 tls /* one location cache for free-list holders */
244 1.17 tls static struct pgfree *px;
245 1.17 tls
246 1.17 tls /* compile-time options */
247 1.17 tls char *malloc_options;
248 1.17 tls
249 1.17 tls /* Name of the current public function */
250 1.17 tls static char *malloc_func;
251 1.17 tls
252 1.17 tls /* Macro for mmap */
253 1.17 tls #define MMAP(size) \
254 1.17 tls mmap(0, (size), PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, \
255 1.17 tls MMAP_FD, 0);
256 1.9 christos
257 1.16 kleink /*
258 1.17 tls * Necessary function declarations
259 1.16 kleink */
260 1.17 tls static int extend_pgdir(u_long index);
261 1.17 tls static void *imalloc(size_t size);
262 1.17 tls static void ifree(void *ptr);
263 1.17 tls static void *irealloc(void *ptr, size_t size);
264 1.17 tls
265 1.17 tls extern char *__progname;
266 1.17 tls
267 1.17 tls static void
268 1.17 tls wrterror(char *p)
269 1.17 tls {
270 1.17 tls char *q = " error: ";
271 1.17 tls write(STDERR_FILENO, __progname, strlen(__progname));
272 1.17 tls write(STDERR_FILENO, malloc_func, strlen(malloc_func));
273 1.17 tls write(STDERR_FILENO, q, strlen(q));
274 1.17 tls write(STDERR_FILENO, p, strlen(p));
275 1.17 tls suicide = 1;
276 1.17 tls abort();
277 1.17 tls }
278 1.17 tls
279 1.16 kleink static void
280 1.17 tls wrtwarning(char *p)
281 1.1 cgd {
282 1.17 tls char *q = " warning: ";
283 1.17 tls if (malloc_abort)
284 1.17 tls wrterror(p);
285 1.17 tls write(STDERR_FILENO, __progname, strlen(__progname));
286 1.17 tls write(STDERR_FILENO, malloc_func, strlen(malloc_func));
287 1.17 tls write(STDERR_FILENO, q, strlen(q));
288 1.17 tls write(STDERR_FILENO, p, strlen(p));
289 1.17 tls }
290 1.17 tls
291 1.16 kleink
292 1.17 tls /*
293 1.17 tls * Allocate a number of pages from the OS
294 1.17 tls */
295 1.17 tls static void *
296 1.17 tls map_pages(int pages)
297 1.17 tls {
298 1.17 tls caddr_t result, tail;
299 1.16 kleink
300 1.17 tls result = (caddr_t)pageround((u_long)sbrk(0));
301 1.17 tls tail = result + (pages << malloc_pageshift);
302 1.17 tls
303 1.17 tls if (brk(tail)) {
304 1.19 thorpej #ifdef MALLOC_EXTRA_SANITY
305 1.17 tls wrterror("(ES): map_pages fails\n");
306 1.19 thorpej #endif /* MALLOC_EXTRA_SANITY */
307 1.17 tls return 0;
308 1.17 tls }
309 1.17 tls
310 1.17 tls last_index = ptr2index(tail) - 1;
311 1.17 tls malloc_brk = tail;
312 1.17 tls
313 1.17 tls if ((last_index+1) >= malloc_ninfo && !extend_pgdir(last_index))
314 1.17 tls return 0;;
315 1.16 kleink
316 1.17 tls return result;
317 1.1 cgd }
318 1.1 cgd
319 1.17 tls /*
320 1.17 tls * Extend page directory
321 1.17 tls */
322 1.17 tls static int
323 1.17 tls extend_pgdir(u_long index)
324 1.1 cgd {
325 1.17 tls struct pginfo **new, **old;
326 1.17 tls int i, oldlen;
327 1.1 cgd
328 1.17 tls /* Make it this many pages */
329 1.17 tls i = index * sizeof *page_dir;
330 1.17 tls i /= malloc_pagesize;
331 1.17 tls i += 2;
332 1.17 tls
333 1.17 tls /* remember the old mapping size */
334 1.17 tls oldlen = malloc_ninfo * sizeof *page_dir;
335 1.17 tls
336 1.17 tls /*
337 1.17 tls * NOTE: we allocate new pages and copy the directory rather than tempt
338 1.17 tls * fate by trying to "grow" the region.. There is nothing to prevent
339 1.17 tls * us from accidently re-mapping space that's been allocated by our caller
340 1.17 tls * via dlopen() or other mmap().
341 1.17 tls *
342 1.17 tls * The copy problem is not too bad, as there is 4K of page index per
343 1.17 tls * 4MB of malloc arena.
344 1.17 tls *
345 1.17 tls * We can totally avoid the copy if we open a file descriptor to associate
346 1.17 tls * the anon mappings with. Then, when we remap the pages at the new
347 1.17 tls * address, the old pages will be "magically" remapped.. But this means
348 1.17 tls * keeping open a "secret" file descriptor.....
349 1.17 tls */
350 1.17 tls
351 1.17 tls /* Get new pages */
352 1.17 tls new = (struct pginfo**) MMAP(i * malloc_pagesize);
353 1.17 tls if (new == (struct pginfo **)-1)
354 1.17 tls return 0;
355 1.17 tls
356 1.17 tls /* Copy the old stuff */
357 1.17 tls memcpy(new, page_dir,
358 1.17 tls malloc_ninfo * sizeof *page_dir);
359 1.17 tls
360 1.17 tls /* register the new size */
361 1.17 tls malloc_ninfo = i * malloc_pagesize / sizeof *page_dir;
362 1.17 tls
363 1.17 tls /* swap the pointers */
364 1.17 tls old = page_dir;
365 1.17 tls page_dir = new;
366 1.17 tls
367 1.17 tls /* Now free the old stuff */
368 1.17 tls munmap(old, oldlen);
369 1.17 tls return 1;
370 1.17 tls }
371 1.16 kleink
372 1.17 tls /*
373 1.17 tls * Initialize the world
374 1.17 tls */
375 1.17 tls static void
376 1.17 tls malloc_init (void)
377 1.17 tls {
378 1.17 tls char *p, b[64];
379 1.17 tls int i, j;
380 1.17 tls int errnosave;
381 1.20 thorpej
382 1.20 thorpej /*
383 1.20 thorpej * Compute page-size related variables.
384 1.20 thorpej */
385 1.20 thorpej malloc_pagesize = sysconf(_SC_PAGESIZE);
386 1.20 thorpej malloc_pagemask = malloc_pagesize - 1;
387 1.20 thorpej for (malloc_pageshift = 0;
388 1.20 thorpej (1UL << malloc_pageshift) != malloc_pagesize;
389 1.20 thorpej malloc_pageshift++)
390 1.20 thorpej /* nothing */ ;
391 1.17 tls
392 1.17 tls INIT_MMAP();
393 1.17 tls
394 1.19 thorpej #ifdef MALLOC_EXTRA_SANITY
395 1.17 tls malloc_junk = 1;
396 1.19 thorpej #endif /* MALLOC_EXTRA_SANITY */
397 1.17 tls
398 1.17 tls for (i = 0; i < 3; i++) {
399 1.17 tls if (i == 0) {
400 1.17 tls errnosave = errno;
401 1.17 tls j = readlink("/etc/malloc.conf", b, sizeof b - 1);
402 1.17 tls errno = errnosave;
403 1.17 tls if (j <= 0)
404 1.17 tls continue;
405 1.17 tls b[j] = '\0';
406 1.17 tls p = b;
407 1.17 tls } else if (i == 1) {
408 1.17 tls p = getenv("MALLOC_OPTIONS");
409 1.17 tls } else {
410 1.17 tls p = malloc_options;
411 1.1 cgd }
412 1.17 tls for (; p && *p; p++) {
413 1.17 tls switch (*p) {
414 1.17 tls case '>': malloc_cache <<= 1; break;
415 1.17 tls case '<': malloc_cache >>= 1; break;
416 1.17 tls case 'a': malloc_abort = 0; break;
417 1.17 tls case 'A': malloc_abort = 1; break;
418 1.17 tls case 'h': malloc_hint = 0; break;
419 1.17 tls case 'H': malloc_hint = 1; break;
420 1.17 tls case 'r': malloc_realloc = 0; break;
421 1.17 tls case 'R': malloc_realloc = 1; break;
422 1.17 tls case 'j': malloc_junk = 0; break;
423 1.17 tls case 'J': malloc_junk = 1; break;
424 1.17 tls #ifdef HAS_UTRACE
425 1.17 tls case 'u': malloc_utrace = 0; break;
426 1.17 tls case 'U': malloc_utrace = 1; break;
427 1.17 tls #endif
428 1.17 tls case 'v': malloc_sysv = 0; break;
429 1.17 tls case 'V': malloc_sysv = 1; break;
430 1.17 tls case 'x': malloc_xmalloc = 0; break;
431 1.17 tls case 'X': malloc_xmalloc = 1; break;
432 1.17 tls case 'z': malloc_zero = 0; break;
433 1.17 tls case 'Z': malloc_zero = 1; break;
434 1.17 tls default:
435 1.17 tls j = malloc_abort;
436 1.17 tls malloc_abort = 0;
437 1.17 tls wrtwarning("unknown char in MALLOC_OPTIONS\n");
438 1.17 tls malloc_abort = j;
439 1.17 tls break;
440 1.17 tls }
441 1.1 cgd }
442 1.17 tls }
443 1.17 tls
444 1.17 tls UTRACE(0, 0, 0);
445 1.17 tls
446 1.17 tls /*
447 1.17 tls * We want junk in the entire allocation, and zero only in the part
448 1.17 tls * the user asked for.
449 1.17 tls */
450 1.17 tls if (malloc_zero)
451 1.17 tls malloc_junk=1;
452 1.17 tls
453 1.17 tls /*
454 1.17 tls * If we run with junk (or implicitly from above: zero), we want to
455 1.17 tls * force realloc() to get new storage, so we can DTRT with it.
456 1.17 tls */
457 1.17 tls if (malloc_junk)
458 1.17 tls malloc_realloc=1;
459 1.17 tls
460 1.17 tls /* Allocate one page for the page directory */
461 1.17 tls page_dir = (struct pginfo **) MMAP(malloc_pagesize);
462 1.17 tls
463 1.17 tls if (page_dir == (struct pginfo **) -1)
464 1.17 tls wrterror("mmap(2) failed, check limits.\n");
465 1.17 tls
466 1.17 tls /*
467 1.17 tls * We need a maximum of malloc_pageshift buckets, steal these from the
468 1.17 tls * front of the page_directory;
469 1.17 tls */
470 1.17 tls malloc_origo = ((u_long)pageround((u_long)sbrk(0))) >> malloc_pageshift;
471 1.17 tls malloc_origo -= malloc_pageshift;
472 1.17 tls
473 1.17 tls malloc_ninfo = malloc_pagesize / sizeof *page_dir;
474 1.17 tls
475 1.17 tls /* Recalculate the cache size in bytes, and make sure it's nonzero */
476 1.17 tls
477 1.17 tls if (!malloc_cache)
478 1.17 tls malloc_cache++;
479 1.17 tls
480 1.17 tls malloc_cache <<= malloc_pageshift;
481 1.17 tls
482 1.17 tls /*
483 1.17 tls * This is a nice hack from Kaleb Keithly (kaleb (at) x.org).
484 1.17 tls * We can sbrk(2) further back when we keep this on a low address.
485 1.17 tls */
486 1.17 tls px = (struct pgfree *) imalloc (sizeof *px);
487 1.17 tls
488 1.17 tls /* Been here, done that */
489 1.17 tls malloc_started++;
490 1.17 tls }
491 1.17 tls
492 1.17 tls /*
493 1.17 tls * Allocate a number of complete pages
494 1.17 tls */
495 1.17 tls static void *
496 1.17 tls malloc_pages(size_t size)
497 1.17 tls {
498 1.17 tls void *p, *delay_free = 0;
499 1.17 tls int i;
500 1.17 tls struct pgfree *pf;
501 1.17 tls u_long index;
502 1.17 tls
503 1.17 tls size = pageround(size);
504 1.17 tls
505 1.17 tls p = 0;
506 1.17 tls
507 1.17 tls /* Look for free pages before asking for more */
508 1.17 tls for(pf = free_list.next; pf; pf = pf->next) {
509 1.17 tls
510 1.19 thorpej #ifdef MALLOC_EXTRA_SANITY
511 1.17 tls if (pf->size & malloc_pagemask)
512 1.17 tls wrterror("(ES): junk length entry on free_list\n");
513 1.17 tls if (!pf->size)
514 1.17 tls wrterror("(ES): zero length entry on free_list\n");
515 1.17 tls if (pf->page == pf->end)
516 1.17 tls wrterror("(ES): zero entry on free_list\n");
517 1.17 tls if (pf->page > pf->end)
518 1.17 tls wrterror("(ES): sick entry on free_list\n");
519 1.17 tls if ((void*)pf->page >= (void*)sbrk(0))
520 1.17 tls wrterror("(ES): entry on free_list past brk\n");
521 1.17 tls if (page_dir[ptr2index(pf->page)] != MALLOC_FREE)
522 1.17 tls wrterror("(ES): non-free first page on free-list\n");
523 1.17 tls if (page_dir[ptr2index(pf->end)-1] != MALLOC_FREE)
524 1.17 tls wrterror("(ES): non-free last page on free-list\n");
525 1.19 thorpej #endif /* MALLOC_EXTRA_SANITY */
526 1.17 tls
527 1.17 tls if (pf->size < size)
528 1.17 tls continue;
529 1.17 tls
530 1.17 tls if (pf->size == size) {
531 1.17 tls p = pf->page;
532 1.17 tls if (pf->next)
533 1.17 tls pf->next->prev = pf->prev;
534 1.17 tls pf->prev->next = pf->next;
535 1.17 tls delay_free = pf;
536 1.17 tls break;
537 1.17 tls }
538 1.17 tls
539 1.17 tls p = pf->page;
540 1.17 tls pf->page = (char *)pf->page + size;
541 1.17 tls pf->size -= size;
542 1.17 tls break;
543 1.17 tls }
544 1.17 tls
545 1.19 thorpej #ifdef MALLOC_EXTRA_SANITY
546 1.17 tls if (p && page_dir[ptr2index(p)] != MALLOC_FREE)
547 1.17 tls wrterror("(ES): allocated non-free page on free-list\n");
548 1.19 thorpej #endif /* MALLOC_EXTRA_SANITY */
549 1.17 tls
550 1.17 tls size >>= malloc_pageshift;
551 1.17 tls
552 1.17 tls /* Map new pages */
553 1.17 tls if (!p)
554 1.17 tls p = map_pages(size);
555 1.17 tls
556 1.17 tls if (p) {
557 1.17 tls
558 1.17 tls index = ptr2index(p);
559 1.17 tls page_dir[index] = MALLOC_FIRST;
560 1.17 tls for (i=1;i<size;i++)
561 1.17 tls page_dir[index+i] = MALLOC_FOLLOW;
562 1.17 tls
563 1.17 tls if (malloc_junk)
564 1.17 tls memset(p, SOME_JUNK, size << malloc_pageshift);
565 1.17 tls }
566 1.17 tls
567 1.17 tls if (delay_free) {
568 1.17 tls if (!px)
569 1.17 tls px = delay_free;
570 1.17 tls else
571 1.17 tls ifree(delay_free);
572 1.17 tls }
573 1.17 tls
574 1.17 tls return p;
575 1.17 tls }
576 1.17 tls
577 1.17 tls /*
578 1.17 tls * Allocate a page of fragments
579 1.17 tls */
580 1.17 tls
581 1.17 tls static __inline__ int
582 1.17 tls malloc_make_chunks(int bits)
583 1.17 tls {
584 1.17 tls struct pginfo *bp;
585 1.17 tls void *pp;
586 1.17 tls int i, k, l;
587 1.17 tls
588 1.17 tls /* Allocate a new bucket */
589 1.17 tls pp = malloc_pages(malloc_pagesize);
590 1.17 tls if (!pp)
591 1.17 tls return 0;
592 1.17 tls
593 1.17 tls /* Find length of admin structure */
594 1.17 tls l = offsetof(struct pginfo, bits[0]);
595 1.17 tls l += sizeof bp->bits[0] *
596 1.17 tls (((malloc_pagesize >> bits)+MALLOC_BITS-1) / MALLOC_BITS);
597 1.17 tls
598 1.17 tls /* Don't waste more than two chunks on this */
599 1.17 tls if ((1<<(bits)) <= l+l) {
600 1.17 tls bp = (struct pginfo *)pp;
601 1.17 tls } else {
602 1.17 tls bp = (struct pginfo *)imalloc(l);
603 1.17 tls if (!bp) {
604 1.17 tls ifree(pp);
605 1.17 tls return 0;
606 1.1 cgd }
607 1.17 tls }
608 1.17 tls
609 1.17 tls bp->size = (1<<bits);
610 1.17 tls bp->shift = bits;
611 1.17 tls bp->total = bp->free = malloc_pagesize >> bits;
612 1.17 tls bp->page = pp;
613 1.17 tls
614 1.17 tls /* set all valid bits in the bitmap */
615 1.17 tls k = bp->total;
616 1.17 tls i = 0;
617 1.17 tls
618 1.17 tls /* Do a bunch at a time */
619 1.17 tls for(;k-i >= MALLOC_BITS; i += MALLOC_BITS)
620 1.17 tls bp->bits[i / MALLOC_BITS] = ~0;
621 1.17 tls
622 1.17 tls for(; i < k; i++)
623 1.17 tls bp->bits[i/MALLOC_BITS] |= 1<<(i%MALLOC_BITS);
624 1.17 tls
625 1.17 tls if (bp == bp->page) {
626 1.17 tls /* Mark the ones we stole for ourselves */
627 1.17 tls for(i=0;l > 0;i++) {
628 1.17 tls bp->bits[i/MALLOC_BITS] &= ~(1<<(i%MALLOC_BITS));
629 1.17 tls bp->free--;
630 1.17 tls bp->total--;
631 1.17 tls l -= (1 << bits);
632 1.1 cgd }
633 1.17 tls }
634 1.17 tls
635 1.17 tls /* MALLOC_LOCK */
636 1.17 tls
637 1.17 tls page_dir[ptr2index(pp)] = bp;
638 1.17 tls
639 1.17 tls bp->next = page_dir[bits];
640 1.17 tls page_dir[bits] = bp;
641 1.17 tls
642 1.17 tls /* MALLOC_UNLOCK */
643 1.17 tls
644 1.17 tls return 1;
645 1.1 cgd }
646 1.1 cgd
647 1.1 cgd /*
648 1.17 tls * Allocate a fragment
649 1.1 cgd */
650 1.17 tls static void *
651 1.17 tls malloc_bytes(size_t size)
652 1.1 cgd {
653 1.17 tls int i,j;
654 1.17 tls u_int u;
655 1.17 tls struct pginfo *bp;
656 1.17 tls int k;
657 1.17 tls u_int *lp;
658 1.17 tls
659 1.17 tls /* Don't bother with anything less than this */
660 1.17 tls if (size < malloc_minsize)
661 1.17 tls size = malloc_minsize;
662 1.17 tls
663 1.17 tls /* Find the right bucket */
664 1.17 tls j = 1;
665 1.17 tls i = size-1;
666 1.17 tls while (i >>= 1)
667 1.17 tls j++;
668 1.17 tls
669 1.17 tls /* If it's empty, make a page more of that size chunks */
670 1.17 tls if (!page_dir[j] && !malloc_make_chunks(j))
671 1.17 tls return 0;
672 1.17 tls
673 1.17 tls bp = page_dir[j];
674 1.17 tls
675 1.17 tls /* Find first word of bitmap which isn't empty */
676 1.17 tls for (lp = bp->bits; !*lp; lp++)
677 1.17 tls ;
678 1.17 tls
679 1.17 tls /* Find that bit, and tweak it */
680 1.17 tls u = 1;
681 1.17 tls k = 0;
682 1.17 tls while (!(*lp & u)) {
683 1.17 tls u += u;
684 1.17 tls k++;
685 1.17 tls }
686 1.17 tls *lp ^= u;
687 1.17 tls
688 1.17 tls /* If there are no more free, remove from free-list */
689 1.17 tls if (!--bp->free) {
690 1.17 tls page_dir[j] = bp->next;
691 1.17 tls bp->next = 0;
692 1.17 tls }
693 1.17 tls
694 1.17 tls /* Adjust to the real offset of that chunk */
695 1.17 tls k += (lp-bp->bits)*MALLOC_BITS;
696 1.17 tls k <<= bp->shift;
697 1.17 tls
698 1.17 tls if (malloc_junk)
699 1.17 tls memset((u_char*)bp->page + k, SOME_JUNK, bp->size);
700 1.1 cgd
701 1.17 tls return (u_char *)bp->page + k;
702 1.1 cgd }
703 1.1 cgd
704 1.17 tls /*
705 1.17 tls * Allocate a piece of memory
706 1.17 tls */
707 1.17 tls static void *
708 1.17 tls imalloc(size_t size)
709 1.17 tls {
710 1.17 tls void *result;
711 1.17 tls
712 1.17 tls if (suicide)
713 1.17 tls abort();
714 1.17 tls
715 1.17 tls if ((size + malloc_pagesize) < size) /* Check for overflow */
716 1.17 tls result = 0;
717 1.17 tls else if (size <= malloc_maxsize)
718 1.17 tls result = malloc_bytes(size);
719 1.17 tls else
720 1.17 tls result = malloc_pages(size);
721 1.17 tls
722 1.17 tls if (malloc_abort && !result)
723 1.17 tls wrterror("allocation failed.\n");
724 1.17 tls
725 1.17 tls if (malloc_zero && result)
726 1.17 tls memset(result, 0, size);
727 1.17 tls
728 1.17 tls return result;
729 1.1 cgd }
730 1.1 cgd
731 1.1 cgd /*
732 1.17 tls * Change the size of an allocation.
733 1.1 cgd */
734 1.17 tls static void *
735 1.17 tls irealloc(void *ptr, size_t size)
736 1.17 tls {
737 1.17 tls void *p;
738 1.17 tls u_long osize, index;
739 1.17 tls struct pginfo **mp;
740 1.17 tls int i;
741 1.17 tls
742 1.17 tls if (suicide)
743 1.17 tls abort();
744 1.17 tls
745 1.17 tls index = ptr2index(ptr);
746 1.1 cgd
747 1.17 tls if (index < malloc_pageshift) {
748 1.17 tls wrtwarning("junk pointer, too low to make sense.\n");
749 1.17 tls return 0;
750 1.17 tls }
751 1.17 tls
752 1.17 tls if (index > last_index) {
753 1.17 tls wrtwarning("junk pointer, too high to make sense.\n");
754 1.17 tls return 0;
755 1.17 tls }
756 1.17 tls
757 1.17 tls mp = &page_dir[index];
758 1.17 tls
759 1.17 tls if (*mp == MALLOC_FIRST) { /* Page allocation */
760 1.17 tls
761 1.17 tls /* Check the pointer */
762 1.17 tls if ((u_long)ptr & malloc_pagemask) {
763 1.17 tls wrtwarning("modified (page-) pointer.\n");
764 1.17 tls return 0;
765 1.17 tls }
766 1.17 tls
767 1.17 tls /* Find the size in bytes */
768 1.17 tls for (osize = malloc_pagesize; *++mp == MALLOC_FOLLOW;)
769 1.17 tls osize += malloc_pagesize;
770 1.17 tls
771 1.17 tls if (!malloc_realloc && /* unless we have to, */
772 1.17 tls size <= osize && /* .. or are too small, */
773 1.17 tls size > (osize - malloc_pagesize)) { /* .. or can free a page, */
774 1.17 tls return ptr; /* don't do anything. */
775 1.6 jtc }
776 1.17 tls
777 1.17 tls } else if (*mp >= MALLOC_MAGIC) { /* Chunk allocation */
778 1.17 tls
779 1.17 tls /* Check the pointer for sane values */
780 1.17 tls if (((u_long)ptr & ((*mp)->size-1))) {
781 1.17 tls wrtwarning("modified (chunk-) pointer.\n");
782 1.17 tls return 0;
783 1.1 cgd }
784 1.17 tls
785 1.17 tls /* Find the chunk index in the page */
786 1.17 tls i = ((u_long)ptr & malloc_pagemask) >> (*mp)->shift;
787 1.17 tls
788 1.17 tls /* Verify that it isn't a free chunk already */
789 1.17 tls if ((*mp)->bits[i/MALLOC_BITS] & (1<<(i%MALLOC_BITS))) {
790 1.17 tls wrtwarning("chunk is already free.\n");
791 1.17 tls return 0;
792 1.16 kleink }
793 1.17 tls
794 1.17 tls osize = (*mp)->size;
795 1.17 tls
796 1.17 tls if (!malloc_realloc && /* Unless we have to, */
797 1.17 tls size < osize && /* ..or are too small, */
798 1.17 tls (size > osize/2 || /* ..or could use a smaller size, */
799 1.17 tls osize == malloc_minsize)) { /* ..(if there is one) */
800 1.17 tls return ptr; /* ..Don't do anything */
801 1.1 cgd }
802 1.17 tls
803 1.17 tls } else {
804 1.17 tls wrtwarning("pointer to wrong page.\n");
805 1.17 tls return 0;
806 1.17 tls }
807 1.17 tls
808 1.17 tls p = imalloc(size);
809 1.17 tls
810 1.17 tls if (p) {
811 1.17 tls /* copy the lesser of the two sizes, and free the old one */
812 1.17 tls if (!size || !osize)
813 1.17 tls ;
814 1.17 tls else if (osize < size)
815 1.17 tls memcpy(p, ptr, osize);
816 1.17 tls else
817 1.17 tls memcpy(p, ptr, size);
818 1.17 tls ifree(ptr);
819 1.17 tls }
820 1.17 tls return p;
821 1.1 cgd }
822 1.1 cgd
823 1.1 cgd /*
824 1.17 tls * Free a sequence of pages
825 1.1 cgd */
826 1.17 tls
827 1.17 tls static __inline__ void
828 1.17 tls free_pages(void *ptr, int index, struct pginfo *info)
829 1.17 tls {
830 1.17 tls int i;
831 1.17 tls struct pgfree *pf, *pt=0;
832 1.17 tls u_long l;
833 1.17 tls void *tail;
834 1.17 tls
835 1.17 tls if (info == MALLOC_FREE) {
836 1.17 tls wrtwarning("page is already free.\n");
837 1.17 tls return;
838 1.17 tls }
839 1.17 tls
840 1.17 tls if (info != MALLOC_FIRST) {
841 1.17 tls wrtwarning("pointer to wrong page.\n");
842 1.17 tls return;
843 1.17 tls }
844 1.17 tls
845 1.17 tls if ((u_long)ptr & malloc_pagemask) {
846 1.17 tls wrtwarning("modified (page-) pointer.\n");
847 1.17 tls return;
848 1.17 tls }
849 1.17 tls
850 1.17 tls /* Count how many pages and mark them free at the same time */
851 1.17 tls page_dir[index] = MALLOC_FREE;
852 1.17 tls for (i = 1; page_dir[index+i] == MALLOC_FOLLOW; i++)
853 1.17 tls page_dir[index + i] = MALLOC_FREE;
854 1.17 tls
855 1.17 tls l = i << malloc_pageshift;
856 1.17 tls
857 1.17 tls if (malloc_junk)
858 1.17 tls memset(ptr, SOME_JUNK, l);
859 1.17 tls
860 1.17 tls if (malloc_hint)
861 1.17 tls madvise(ptr, l, MADV_FREE);
862 1.17 tls
863 1.17 tls tail = (char *)ptr+l;
864 1.17 tls
865 1.17 tls /* add to free-list */
866 1.17 tls if (!px)
867 1.17 tls px = imalloc(sizeof *pt); /* This cannot fail... */
868 1.17 tls px->page = ptr;
869 1.17 tls px->end = tail;
870 1.17 tls px->size = l;
871 1.17 tls if (!free_list.next) {
872 1.17 tls
873 1.17 tls /* Nothing on free list, put this at head */
874 1.17 tls px->next = free_list.next;
875 1.17 tls px->prev = &free_list;
876 1.17 tls free_list.next = px;
877 1.17 tls pf = px;
878 1.17 tls px = 0;
879 1.17 tls
880 1.17 tls } else {
881 1.17 tls
882 1.17 tls /* Find the right spot, leave pf pointing to the modified entry. */
883 1.17 tls tail = (char *)ptr+l;
884 1.17 tls
885 1.17 tls for(pf = free_list.next; pf->end < ptr && pf->next; pf = pf->next)
886 1.17 tls ; /* Race ahead here */
887 1.17 tls
888 1.17 tls if (pf->page > tail) {
889 1.17 tls /* Insert before entry */
890 1.17 tls px->next = pf;
891 1.17 tls px->prev = pf->prev;
892 1.17 tls pf->prev = px;
893 1.17 tls px->prev->next = px;
894 1.17 tls pf = px;
895 1.17 tls px = 0;
896 1.17 tls } else if (pf->end == ptr ) {
897 1.17 tls /* Append to the previous entry */
898 1.17 tls pf->end = (char *)pf->end + l;
899 1.17 tls pf->size += l;
900 1.17 tls if (pf->next && pf->end == pf->next->page ) {
901 1.17 tls /* And collapse the next too. */
902 1.17 tls pt = pf->next;
903 1.17 tls pf->end = pt->end;
904 1.17 tls pf->size += pt->size;
905 1.17 tls pf->next = pt->next;
906 1.17 tls if (pf->next)
907 1.17 tls pf->next->prev = pf;
908 1.17 tls }
909 1.17 tls } else if (pf->page == tail) {
910 1.17 tls /* Prepend to entry */
911 1.17 tls pf->size += l;
912 1.17 tls pf->page = ptr;
913 1.17 tls } else if (!pf->next) {
914 1.17 tls /* Append at tail of chain */
915 1.17 tls px->next = 0;
916 1.17 tls px->prev = pf;
917 1.17 tls pf->next = px;
918 1.17 tls pf = px;
919 1.17 tls px = 0;
920 1.17 tls } else {
921 1.17 tls wrterror("freelist is destroyed.\n");
922 1.1 cgd }
923 1.17 tls }
924 1.17 tls
925 1.17 tls /* Return something to OS ? */
926 1.17 tls if (!pf->next && /* If we're the last one, */
927 1.17 tls pf->size > malloc_cache && /* ..and the cache is full, */
928 1.17 tls pf->end == malloc_brk && /* ..and none behind us, */
929 1.17 tls malloc_brk == sbrk(0)) { /* ..and it's OK to do... */
930 1.17 tls
931 1.17 tls /*
932 1.17 tls * Keep the cache intact. Notice that the '>' above guarantees that
933 1.17 tls * the pf will always have at least one page afterwards.
934 1.17 tls */
935 1.17 tls pf->end = (char *)pf->page + malloc_cache;
936 1.17 tls pf->size = malloc_cache;
937 1.17 tls
938 1.17 tls brk(pf->end);
939 1.17 tls malloc_brk = pf->end;
940 1.17 tls
941 1.17 tls index = ptr2index(pf->end);
942 1.17 tls last_index = index - 1;
943 1.17 tls
944 1.17 tls for(i=index;i <= last_index;)
945 1.17 tls page_dir[i++] = MALLOC_NOT_MINE;
946 1.17 tls
947 1.17 tls /* XXX: We could realloc/shrink the pagedir here I guess. */
948 1.17 tls }
949 1.17 tls if (pt)
950 1.17 tls ifree(pt);
951 1.1 cgd }
952 1.1 cgd
953 1.1 cgd /*
954 1.17 tls * Free a chunk, and possibly the page it's on, if the page becomes empty.
955 1.1 cgd */
956 1.17 tls
957 1.17 tls static __inline__ void
958 1.17 tls free_bytes(void *ptr, int index, struct pginfo *info)
959 1.17 tls {
960 1.17 tls int i;
961 1.17 tls struct pginfo **mp;
962 1.17 tls void *vp;
963 1.17 tls
964 1.17 tls /* Find the chunk number on the page */
965 1.17 tls i = ((u_long)ptr & malloc_pagemask) >> info->shift;
966 1.17 tls
967 1.17 tls if (((u_long)ptr & (info->size-1))) {
968 1.17 tls wrtwarning("modified (chunk-) pointer.\n");
969 1.17 tls return;
970 1.17 tls }
971 1.17 tls
972 1.17 tls if (info->bits[i/MALLOC_BITS] & (1<<(i%MALLOC_BITS))) {
973 1.17 tls wrtwarning("chunk is already free.\n");
974 1.17 tls return;
975 1.17 tls }
976 1.17 tls
977 1.17 tls if (malloc_junk)
978 1.17 tls memset(ptr, SOME_JUNK, info->size);
979 1.17 tls
980 1.17 tls info->bits[i/MALLOC_BITS] |= 1<<(i%MALLOC_BITS);
981 1.17 tls info->free++;
982 1.17 tls
983 1.17 tls mp = page_dir + info->shift;
984 1.17 tls
985 1.17 tls if (info->free == 1) {
986 1.17 tls
987 1.17 tls /* Page became non-full */
988 1.17 tls
989 1.17 tls mp = page_dir + info->shift;
990 1.17 tls /* Insert in address order */
991 1.17 tls while (*mp && (*mp)->next && (*mp)->next->page < info->page)
992 1.17 tls mp = &(*mp)->next;
993 1.17 tls info->next = *mp;
994 1.17 tls *mp = info;
995 1.17 tls return;
996 1.17 tls }
997 1.17 tls
998 1.17 tls if (info->free != info->total)
999 1.17 tls return;
1000 1.17 tls
1001 1.17 tls /* Find & remove this page in the queue */
1002 1.17 tls while (*mp != info) {
1003 1.17 tls mp = &((*mp)->next);
1004 1.19 thorpej #ifdef MALLOC_EXTRA_SANITY
1005 1.17 tls if (!*mp)
1006 1.17 tls wrterror("(ES): Not on queue\n");
1007 1.19 thorpej #endif /* MALLOC_EXTRA_SANITY */
1008 1.17 tls }
1009 1.17 tls *mp = info->next;
1010 1.17 tls
1011 1.17 tls /* Free the page & the info structure if need be */
1012 1.17 tls page_dir[ptr2index(info->page)] = MALLOC_FIRST;
1013 1.17 tls vp = info->page; /* Order is important ! */
1014 1.17 tls if(vp != (void*)info)
1015 1.17 tls ifree(info);
1016 1.17 tls ifree(vp);
1017 1.17 tls }
1018 1.17 tls
1019 1.17 tls static void
1020 1.17 tls ifree(void *ptr)
1021 1.17 tls {
1022 1.17 tls struct pginfo *info;
1023 1.17 tls int index;
1024 1.17 tls
1025 1.17 tls /* This is legal */
1026 1.17 tls if (!ptr)
1027 1.17 tls return;
1028 1.17 tls
1029 1.17 tls if (!malloc_started) {
1030 1.17 tls wrtwarning("malloc() has never been called.\n");
1031 1.17 tls return;
1032 1.17 tls }
1033 1.17 tls
1034 1.17 tls /* If we're already sinking, don't make matters any worse. */
1035 1.17 tls if (suicide)
1036 1.17 tls return;
1037 1.17 tls
1038 1.17 tls index = ptr2index(ptr);
1039 1.17 tls
1040 1.17 tls if (index < malloc_pageshift) {
1041 1.17 tls wrtwarning("junk pointer, too low to make sense.\n");
1042 1.17 tls return;
1043 1.17 tls }
1044 1.17 tls
1045 1.17 tls if (index > last_index) {
1046 1.17 tls wrtwarning("junk pointer, too high to make sense.\n");
1047 1.17 tls return;
1048 1.17 tls }
1049 1.17 tls
1050 1.17 tls info = page_dir[index];
1051 1.17 tls
1052 1.17 tls if (info < MALLOC_MAGIC)
1053 1.17 tls free_pages(ptr, index, info);
1054 1.17 tls else
1055 1.17 tls free_bytes(ptr, index, info);
1056 1.17 tls return;
1057 1.17 tls }
1058 1.17 tls
1059 1.17 tls /*
1060 1.17 tls * These are the public exported interface routines.
1061 1.17 tls */
1062 1.17 tls
1063 1.17 tls
1064 1.17 tls void *
1065 1.17 tls malloc(size_t size)
1066 1.17 tls {
1067 1.17 tls register void *r;
1068 1.17 tls
1069 1.17 tls THREAD_LOCK();
1070 1.17 tls malloc_func = " in malloc():";
1071 1.17 tls if (malloc_active++) {
1072 1.17 tls wrtwarning("recursive call.\n");
1073 1.17 tls malloc_active--;
1074 1.17 tls return (0);
1075 1.17 tls }
1076 1.17 tls if (!malloc_started)
1077 1.17 tls malloc_init();
1078 1.17 tls if (malloc_sysv && !size)
1079 1.17 tls r = 0;
1080 1.17 tls else
1081 1.17 tls r = imalloc(size);
1082 1.17 tls UTRACE(0, size, r);
1083 1.17 tls malloc_active--;
1084 1.17 tls THREAD_UNLOCK();
1085 1.17 tls if (malloc_xmalloc && !r)
1086 1.17 tls wrterror("out of memory.\n");
1087 1.17 tls return (r);
1088 1.17 tls }
1089 1.17 tls
1090 1.9 christos void
1091 1.17 tls free(void *ptr)
1092 1.1 cgd {
1093 1.17 tls THREAD_LOCK();
1094 1.17 tls malloc_func = " in free():";
1095 1.17 tls if (malloc_active++) {
1096 1.17 tls wrtwarning("recursive call.\n");
1097 1.17 tls malloc_active--;
1098 1.17 tls return;
1099 1.17 tls } else {
1100 1.17 tls ifree(ptr);
1101 1.17 tls UTRACE(ptr, 0, 0);
1102 1.17 tls }
1103 1.17 tls malloc_active--;
1104 1.17 tls THREAD_UNLOCK();
1105 1.17 tls return;
1106 1.17 tls }
1107 1.17 tls
1108 1.17 tls void *
1109 1.17 tls realloc(void *ptr, size_t size)
1110 1.17 tls {
1111 1.17 tls register void *r;
1112 1.17 tls
1113 1.17 tls THREAD_LOCK();
1114 1.17 tls malloc_func = " in realloc():";
1115 1.17 tls if (malloc_active++) {
1116 1.17 tls wrtwarning("recursive call.\n");
1117 1.17 tls malloc_active--;
1118 1.17 tls return (0);
1119 1.17 tls }
1120 1.17 tls if (ptr && !malloc_started) {
1121 1.17 tls wrtwarning("malloc() has never been called.\n");
1122 1.17 tls ptr = 0;
1123 1.17 tls }
1124 1.17 tls if (!malloc_started)
1125 1.17 tls malloc_init();
1126 1.17 tls if (malloc_sysv && !size) {
1127 1.17 tls ifree(ptr);
1128 1.17 tls r = 0;
1129 1.17 tls } else if (!ptr) {
1130 1.17 tls r = imalloc(size);
1131 1.17 tls } else {
1132 1.17 tls r = irealloc(ptr, size);
1133 1.17 tls }
1134 1.17 tls UTRACE(ptr, size, r);
1135 1.17 tls malloc_active--;
1136 1.17 tls THREAD_UNLOCK();
1137 1.17 tls if (malloc_xmalloc && !r)
1138 1.17 tls wrterror("out of memory.\n");
1139 1.17 tls return (r);
1140 1.1 cgd }
1141