malloc.c revision 1.32 1 1.32 simonb /* $NetBSD: malloc.c,v 1.32 2000/05/20 15:13:31 simonb 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 1.25 kleink #include "namespace.h"
88 1.16 kleink #include <sys/types.h>
89 1.17 tls #include <sys/mman.h>
90 1.17 tls #include <errno.h>
91 1.17 tls #include <fcntl.h>
92 1.17 tls #include <stddef.h>
93 1.9 christos #include <stdio.h>
94 1.1 cgd #include <stdlib.h>
95 1.1 cgd #include <string.h>
96 1.1 cgd #include <unistd.h>
97 1.1 cgd
98 1.17 tls /*
99 1.17 tls * This structure describes a page worth of chunks.
100 1.17 tls */
101 1.17 tls
102 1.17 tls struct pginfo {
103 1.17 tls struct pginfo *next; /* next on the free list */
104 1.17 tls void *page; /* Pointer to the page */
105 1.17 tls u_short size; /* size of this page's chunks */
106 1.17 tls u_short shift; /* How far to shift for this size chunks */
107 1.17 tls u_short free; /* How many free chunks */
108 1.17 tls u_short total; /* How many chunk */
109 1.17 tls u_int bits[1]; /* Which chunks are free */
110 1.17 tls };
111 1.1 cgd
112 1.1 cgd /*
113 1.17 tls * This structure describes a number of free pages.
114 1.17 tls */
115 1.17 tls
116 1.17 tls struct pgfree {
117 1.17 tls struct pgfree *next; /* next run of free pages */
118 1.17 tls struct pgfree *prev; /* prev run of free pages */
119 1.17 tls void *page; /* pointer to free pages */
120 1.17 tls void *end; /* pointer to end of free pages */
121 1.17 tls size_t size; /* number of bytes free */
122 1.1 cgd };
123 1.1 cgd
124 1.17 tls /*
125 1.17 tls * How many bits per u_int in the bitmap.
126 1.17 tls * Change only if not 8 bits/byte
127 1.17 tls */
128 1.17 tls #define MALLOC_BITS (8*sizeof(u_int))
129 1.17 tls
130 1.17 tls /*
131 1.17 tls * Magic values to put in the page_directory
132 1.17 tls */
133 1.17 tls #define MALLOC_NOT_MINE ((struct pginfo*) 0)
134 1.17 tls #define MALLOC_FREE ((struct pginfo*) 1)
135 1.17 tls #define MALLOC_FIRST ((struct pginfo*) 2)
136 1.17 tls #define MALLOC_FOLLOW ((struct pginfo*) 3)
137 1.17 tls #define MALLOC_MAGIC ((struct pginfo*) 4)
138 1.17 tls
139 1.20 thorpej /*
140 1.20 thorpej * Page size related parameters, computed at run-time.
141 1.20 thorpej */
142 1.20 thorpej static size_t malloc_pagesize;
143 1.20 thorpej static size_t malloc_pageshift;
144 1.20 thorpej static size_t malloc_pagemask;
145 1.17 tls
146 1.17 tls #ifndef malloc_minsize
147 1.17 tls #define malloc_minsize 16U
148 1.17 tls #endif
149 1.17 tls
150 1.17 tls #ifndef malloc_maxsize
151 1.17 tls #define malloc_maxsize ((malloc_pagesize)>>1)
152 1.17 tls #endif
153 1.17 tls
154 1.17 tls #define pageround(foo) (((foo) + (malloc_pagemask))&(~(malloc_pagemask)))
155 1.30 enami #define ptr2idx(foo) (((size_t)(foo) >> malloc_pageshift)-malloc_origo)
156 1.1 cgd
157 1.17 tls #ifndef THREAD_LOCK
158 1.17 tls #define THREAD_LOCK()
159 1.17 tls #endif
160 1.1 cgd
161 1.17 tls #ifndef THREAD_UNLOCK
162 1.17 tls #define THREAD_UNLOCK()
163 1.16 kleink #endif
164 1.16 kleink
165 1.17 tls #ifndef MMAP_FD
166 1.17 tls #define MMAP_FD (-1)
167 1.1 cgd #endif
168 1.1 cgd
169 1.17 tls #ifndef INIT_MMAP
170 1.17 tls #define INIT_MMAP()
171 1.18 thorpej #endif
172 1.18 thorpej
173 1.18 thorpej #ifndef MADV_FREE
174 1.18 thorpej #define MADV_FREE MADV_DONTNEED
175 1.9 christos #endif
176 1.9 christos
177 1.17 tls /* Set when initialization has been done */
178 1.17 tls static unsigned malloc_started;
179 1.17 tls
180 1.17 tls /* Recusion flag for public interface. */
181 1.17 tls static int malloc_active;
182 1.17 tls
183 1.17 tls /* Number of free pages we cache */
184 1.17 tls static unsigned malloc_cache = 16;
185 1.17 tls
186 1.17 tls /* The offset from pagenumber to index into the page directory */
187 1.30 enami static size_t malloc_origo;
188 1.17 tls
189 1.17 tls /* The last index in the page directory we care about */
190 1.30 enami static size_t last_idx;
191 1.17 tls
192 1.17 tls /* Pointer to page directory. Allocated "as if with" malloc */
193 1.17 tls static struct pginfo **page_dir;
194 1.17 tls
195 1.17 tls /* How many slots in the page directory */
196 1.17 tls static unsigned malloc_ninfo;
197 1.17 tls
198 1.17 tls /* Free pages line up here */
199 1.17 tls static struct pgfree free_list;
200 1.17 tls
201 1.17 tls /* Abort(), user doesn't handle problems. */
202 1.17 tls static int malloc_abort;
203 1.17 tls
204 1.17 tls /* Are we trying to die ? */
205 1.17 tls static int suicide;
206 1.17 tls
207 1.17 tls /* always realloc ? */
208 1.17 tls static int malloc_realloc;
209 1.9 christos
210 1.17 tls /* pass the kernel a hint on free pages ? */
211 1.32 simonb static int malloc_hint = 0;
212 1.17 tls
213 1.17 tls /* xmalloc behaviour ? */
214 1.17 tls static int malloc_xmalloc;
215 1.17 tls
216 1.17 tls /* sysv behaviour for malloc(0) ? */
217 1.17 tls static int malloc_sysv;
218 1.17 tls
219 1.17 tls /* zero fill ? */
220 1.17 tls static int malloc_zero;
221 1.17 tls
222 1.17 tls /* junk fill ? */
223 1.17 tls static int malloc_junk;
224 1.17 tls
225 1.17 tls #ifdef HAS_UTRACE
226 1.17 tls
227 1.17 tls /* utrace ? */
228 1.17 tls static int malloc_utrace;
229 1.17 tls
230 1.17 tls struct ut { void *p; size_t s; void *r; };
231 1.17 tls
232 1.17 tls void utrace __P((struct ut *, int));
233 1.17 tls
234 1.17 tls #define UTRACE(a, b, c) \
235 1.17 tls if (malloc_utrace) \
236 1.17 tls {struct ut u; u.p=a; u.s = b; u.r=c; utrace(&u, sizeof u);}
237 1.17 tls #else /* !HAS_UTRACE */
238 1.17 tls #define UTRACE(a,b,c)
239 1.17 tls #endif /* HAS_UTRACE */
240 1.17 tls
241 1.17 tls /* my last break. */
242 1.17 tls static void *malloc_brk;
243 1.17 tls
244 1.17 tls /* one location cache for free-list holders */
245 1.17 tls static struct pgfree *px;
246 1.17 tls
247 1.17 tls /* compile-time options */
248 1.17 tls char *malloc_options;
249 1.17 tls
250 1.17 tls /* Name of the current public function */
251 1.22 thorpej static char *malloc_func;
252 1.17 tls
253 1.17 tls /* Macro for mmap */
254 1.17 tls #define MMAP(size) \
255 1.17 tls mmap(0, (size), PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, \
256 1.30 enami MMAP_FD, (off_t)0);
257 1.9 christos
258 1.16 kleink /*
259 1.17 tls * Necessary function declarations
260 1.16 kleink */
261 1.30 enami static int extend_pgdir(size_t idx);
262 1.17 tls static void *imalloc(size_t size);
263 1.17 tls static void ifree(void *ptr);
264 1.17 tls static void *irealloc(void *ptr, size_t size);
265 1.17 tls
266 1.17 tls extern char *__progname;
267 1.17 tls
268 1.17 tls static void
269 1.22 thorpej wrterror(char *p)
270 1.17 tls {
271 1.22 thorpej char *q = " error: ";
272 1.17 tls write(STDERR_FILENO, __progname, strlen(__progname));
273 1.17 tls write(STDERR_FILENO, malloc_func, strlen(malloc_func));
274 1.17 tls write(STDERR_FILENO, q, strlen(q));
275 1.17 tls write(STDERR_FILENO, p, strlen(p));
276 1.17 tls suicide = 1;
277 1.17 tls abort();
278 1.17 tls }
279 1.17 tls
280 1.16 kleink static void
281 1.22 thorpej wrtwarning(char *p)
282 1.1 cgd {
283 1.22 thorpej char *q = " warning: ";
284 1.17 tls if (malloc_abort)
285 1.17 tls wrterror(p);
286 1.17 tls write(STDERR_FILENO, __progname, strlen(__progname));
287 1.17 tls write(STDERR_FILENO, malloc_func, strlen(malloc_func));
288 1.17 tls write(STDERR_FILENO, q, strlen(q));
289 1.17 tls write(STDERR_FILENO, p, strlen(p));
290 1.17 tls }
291 1.17 tls
292 1.16 kleink
293 1.17 tls /*
294 1.17 tls * Allocate a number of pages from the OS
295 1.17 tls */
296 1.17 tls static void *
297 1.30 enami map_pages(size_t pages)
298 1.17 tls {
299 1.17 tls caddr_t result, tail;
300 1.16 kleink
301 1.30 enami result = (caddr_t)pageround((size_t)sbrk(0));
302 1.17 tls tail = result + (pages << malloc_pageshift);
303 1.17 tls
304 1.17 tls if (brk(tail)) {
305 1.19 thorpej #ifdef MALLOC_EXTRA_SANITY
306 1.17 tls wrterror("(ES): map_pages fails\n");
307 1.19 thorpej #endif /* MALLOC_EXTRA_SANITY */
308 1.17 tls return 0;
309 1.17 tls }
310 1.17 tls
311 1.23 thorpej last_idx = ptr2idx(tail) - 1;
312 1.17 tls malloc_brk = tail;
313 1.17 tls
314 1.23 thorpej if ((last_idx+1) >= malloc_ninfo && !extend_pgdir(last_idx))
315 1.17 tls return 0;;
316 1.16 kleink
317 1.17 tls return result;
318 1.1 cgd }
319 1.1 cgd
320 1.17 tls /*
321 1.17 tls * Extend page directory
322 1.17 tls */
323 1.17 tls static int
324 1.30 enami extend_pgdir(size_t idx)
325 1.1 cgd {
326 1.17 tls struct pginfo **new, **old;
327 1.30 enami size_t newlen, oldlen;
328 1.1 cgd
329 1.17 tls /* Make it this many pages */
330 1.30 enami newlen = pageround(idx * sizeof *page_dir) + malloc_pagesize;
331 1.17 tls
332 1.17 tls /* remember the old mapping size */
333 1.17 tls oldlen = malloc_ninfo * sizeof *page_dir;
334 1.17 tls
335 1.17 tls /*
336 1.17 tls * NOTE: we allocate new pages and copy the directory rather than tempt
337 1.17 tls * fate by trying to "grow" the region.. There is nothing to prevent
338 1.17 tls * us from accidently re-mapping space that's been allocated by our caller
339 1.17 tls * via dlopen() or other mmap().
340 1.17 tls *
341 1.17 tls * The copy problem is not too bad, as there is 4K of page index per
342 1.17 tls * 4MB of malloc arena.
343 1.17 tls *
344 1.17 tls * We can totally avoid the copy if we open a file descriptor to associate
345 1.17 tls * the anon mappings with. Then, when we remap the pages at the new
346 1.17 tls * address, the old pages will be "magically" remapped.. But this means
347 1.17 tls * keeping open a "secret" file descriptor.....
348 1.17 tls */
349 1.17 tls
350 1.17 tls /* Get new pages */
351 1.30 enami new = (struct pginfo**) MMAP(newlen);
352 1.17 tls if (new == (struct pginfo **)-1)
353 1.17 tls return 0;
354 1.17 tls
355 1.17 tls /* Copy the old stuff */
356 1.30 enami memcpy(new, page_dir, oldlen);
357 1.17 tls
358 1.17 tls /* register the new size */
359 1.30 enami malloc_ninfo = newlen / sizeof *page_dir;
360 1.17 tls
361 1.17 tls /* swap the pointers */
362 1.17 tls old = page_dir;
363 1.17 tls page_dir = new;
364 1.17 tls
365 1.17 tls /* Now free the old stuff */
366 1.17 tls munmap(old, oldlen);
367 1.17 tls return 1;
368 1.17 tls }
369 1.16 kleink
370 1.17 tls /*
371 1.17 tls * Initialize the world
372 1.17 tls */
373 1.17 tls static void
374 1.17 tls malloc_init (void)
375 1.17 tls {
376 1.17 tls char *p, b[64];
377 1.17 tls int i, j;
378 1.17 tls int errnosave;
379 1.20 thorpej
380 1.20 thorpej /*
381 1.20 thorpej * Compute page-size related variables.
382 1.20 thorpej */
383 1.30 enami malloc_pagesize = (size_t)sysconf(_SC_PAGESIZE);
384 1.20 thorpej malloc_pagemask = malloc_pagesize - 1;
385 1.20 thorpej for (malloc_pageshift = 0;
386 1.20 thorpej (1UL << malloc_pageshift) != malloc_pagesize;
387 1.20 thorpej malloc_pageshift++)
388 1.20 thorpej /* nothing */ ;
389 1.17 tls
390 1.17 tls INIT_MMAP();
391 1.17 tls
392 1.19 thorpej #ifdef MALLOC_EXTRA_SANITY
393 1.17 tls malloc_junk = 1;
394 1.19 thorpej #endif /* MALLOC_EXTRA_SANITY */
395 1.17 tls
396 1.17 tls for (i = 0; i < 3; i++) {
397 1.17 tls if (i == 0) {
398 1.17 tls errnosave = errno;
399 1.17 tls j = readlink("/etc/malloc.conf", b, sizeof b - 1);
400 1.17 tls errno = errnosave;
401 1.17 tls if (j <= 0)
402 1.17 tls continue;
403 1.17 tls b[j] = '\0';
404 1.17 tls p = b;
405 1.17 tls } else if (i == 1) {
406 1.17 tls p = getenv("MALLOC_OPTIONS");
407 1.17 tls } else {
408 1.17 tls p = malloc_options;
409 1.1 cgd }
410 1.17 tls for (; p && *p; p++) {
411 1.17 tls switch (*p) {
412 1.17 tls case '>': malloc_cache <<= 1; break;
413 1.17 tls case '<': malloc_cache >>= 1; break;
414 1.17 tls case 'a': malloc_abort = 0; break;
415 1.17 tls case 'A': malloc_abort = 1; break;
416 1.17 tls case 'h': malloc_hint = 0; break;
417 1.17 tls case 'H': malloc_hint = 1; break;
418 1.17 tls case 'r': malloc_realloc = 0; break;
419 1.17 tls case 'R': malloc_realloc = 1; break;
420 1.17 tls case 'j': malloc_junk = 0; break;
421 1.17 tls case 'J': malloc_junk = 1; break;
422 1.17 tls #ifdef HAS_UTRACE
423 1.17 tls case 'u': malloc_utrace = 0; break;
424 1.17 tls case 'U': malloc_utrace = 1; break;
425 1.17 tls #endif
426 1.17 tls case 'v': malloc_sysv = 0; break;
427 1.17 tls case 'V': malloc_sysv = 1; break;
428 1.17 tls case 'x': malloc_xmalloc = 0; break;
429 1.17 tls case 'X': malloc_xmalloc = 1; break;
430 1.17 tls case 'z': malloc_zero = 0; break;
431 1.17 tls case 'Z': malloc_zero = 1; break;
432 1.17 tls default:
433 1.17 tls j = malloc_abort;
434 1.17 tls malloc_abort = 0;
435 1.17 tls wrtwarning("unknown char in MALLOC_OPTIONS\n");
436 1.17 tls malloc_abort = j;
437 1.17 tls break;
438 1.17 tls }
439 1.1 cgd }
440 1.17 tls }
441 1.17 tls
442 1.17 tls UTRACE(0, 0, 0);
443 1.17 tls
444 1.17 tls /*
445 1.17 tls * We want junk in the entire allocation, and zero only in the part
446 1.17 tls * the user asked for.
447 1.17 tls */
448 1.17 tls if (malloc_zero)
449 1.17 tls malloc_junk=1;
450 1.17 tls
451 1.17 tls /*
452 1.17 tls * If we run with junk (or implicitly from above: zero), we want to
453 1.17 tls * force realloc() to get new storage, so we can DTRT with it.
454 1.17 tls */
455 1.17 tls if (malloc_junk)
456 1.17 tls malloc_realloc=1;
457 1.17 tls
458 1.17 tls /* Allocate one page for the page directory */
459 1.17 tls page_dir = (struct pginfo **) MMAP(malloc_pagesize);
460 1.17 tls
461 1.17 tls if (page_dir == (struct pginfo **) -1)
462 1.17 tls wrterror("mmap(2) failed, check limits.\n");
463 1.17 tls
464 1.17 tls /*
465 1.17 tls * We need a maximum of malloc_pageshift buckets, steal these from the
466 1.17 tls * front of the page_directory;
467 1.17 tls */
468 1.30 enami malloc_origo = pageround((size_t)sbrk(0)) >> malloc_pageshift;
469 1.17 tls malloc_origo -= malloc_pageshift;
470 1.17 tls
471 1.17 tls malloc_ninfo = malloc_pagesize / sizeof *page_dir;
472 1.17 tls
473 1.17 tls /* Recalculate the cache size in bytes, and make sure it's nonzero */
474 1.17 tls
475 1.17 tls if (!malloc_cache)
476 1.17 tls malloc_cache++;
477 1.17 tls
478 1.17 tls malloc_cache <<= malloc_pageshift;
479 1.17 tls
480 1.17 tls /*
481 1.17 tls * This is a nice hack from Kaleb Keithly (kaleb (at) x.org).
482 1.17 tls * We can sbrk(2) further back when we keep this on a low address.
483 1.17 tls */
484 1.17 tls px = (struct pgfree *) imalloc (sizeof *px);
485 1.17 tls
486 1.17 tls /* Been here, done that */
487 1.17 tls malloc_started++;
488 1.17 tls }
489 1.17 tls
490 1.17 tls /*
491 1.17 tls * Allocate a number of complete pages
492 1.17 tls */
493 1.17 tls static void *
494 1.17 tls malloc_pages(size_t size)
495 1.17 tls {
496 1.17 tls void *p, *delay_free = 0;
497 1.17 tls int i;
498 1.17 tls struct pgfree *pf;
499 1.30 enami size_t idx;
500 1.17 tls
501 1.17 tls size = pageround(size);
502 1.17 tls
503 1.17 tls p = 0;
504 1.17 tls
505 1.17 tls /* Look for free pages before asking for more */
506 1.17 tls for(pf = free_list.next; pf; pf = pf->next) {
507 1.17 tls
508 1.19 thorpej #ifdef MALLOC_EXTRA_SANITY
509 1.17 tls if (pf->size & malloc_pagemask)
510 1.17 tls wrterror("(ES): junk length entry on free_list\n");
511 1.17 tls if (!pf->size)
512 1.17 tls wrterror("(ES): zero length entry on free_list\n");
513 1.17 tls if (pf->page == pf->end)
514 1.17 tls wrterror("(ES): zero entry on free_list\n");
515 1.17 tls if (pf->page > pf->end)
516 1.17 tls wrterror("(ES): sick entry on free_list\n");
517 1.17 tls if ((void*)pf->page >= (void*)sbrk(0))
518 1.17 tls wrterror("(ES): entry on free_list past brk\n");
519 1.23 thorpej if (page_dir[ptr2idx(pf->page)] != MALLOC_FREE)
520 1.17 tls wrterror("(ES): non-free first page on free-list\n");
521 1.23 thorpej if (page_dir[ptr2idx(pf->end)-1] != MALLOC_FREE)
522 1.17 tls wrterror("(ES): non-free last page on free-list\n");
523 1.19 thorpej #endif /* MALLOC_EXTRA_SANITY */
524 1.17 tls
525 1.17 tls if (pf->size < size)
526 1.17 tls continue;
527 1.17 tls
528 1.17 tls if (pf->size == size) {
529 1.17 tls p = pf->page;
530 1.17 tls if (pf->next)
531 1.17 tls pf->next->prev = pf->prev;
532 1.17 tls pf->prev->next = pf->next;
533 1.17 tls delay_free = pf;
534 1.17 tls break;
535 1.17 tls }
536 1.17 tls
537 1.17 tls p = pf->page;
538 1.17 tls pf->page = (char *)pf->page + size;
539 1.17 tls pf->size -= size;
540 1.17 tls break;
541 1.17 tls }
542 1.17 tls
543 1.19 thorpej #ifdef MALLOC_EXTRA_SANITY
544 1.23 thorpej if (p && page_dir[ptr2idx(p)] != MALLOC_FREE)
545 1.17 tls wrterror("(ES): allocated non-free page on free-list\n");
546 1.19 thorpej #endif /* MALLOC_EXTRA_SANITY */
547 1.17 tls
548 1.17 tls size >>= malloc_pageshift;
549 1.17 tls
550 1.17 tls /* Map new pages */
551 1.17 tls if (!p)
552 1.17 tls p = map_pages(size);
553 1.17 tls
554 1.17 tls if (p) {
555 1.17 tls
556 1.23 thorpej idx = ptr2idx(p);
557 1.23 thorpej page_dir[idx] = MALLOC_FIRST;
558 1.17 tls for (i=1;i<size;i++)
559 1.23 thorpej page_dir[idx+i] = MALLOC_FOLLOW;
560 1.17 tls
561 1.17 tls if (malloc_junk)
562 1.17 tls memset(p, SOME_JUNK, size << malloc_pageshift);
563 1.17 tls }
564 1.17 tls
565 1.17 tls if (delay_free) {
566 1.17 tls if (!px)
567 1.17 tls px = delay_free;
568 1.17 tls else
569 1.17 tls ifree(delay_free);
570 1.17 tls }
571 1.17 tls
572 1.17 tls return p;
573 1.17 tls }
574 1.17 tls
575 1.17 tls /*
576 1.17 tls * Allocate a page of fragments
577 1.17 tls */
578 1.17 tls
579 1.17 tls static __inline__ int
580 1.17 tls malloc_make_chunks(int bits)
581 1.17 tls {
582 1.17 tls struct pginfo *bp;
583 1.17 tls void *pp;
584 1.31 enami int i, k, l;
585 1.17 tls
586 1.17 tls /* Allocate a new bucket */
587 1.17 tls pp = malloc_pages(malloc_pagesize);
588 1.17 tls if (!pp)
589 1.17 tls return 0;
590 1.17 tls
591 1.17 tls /* Find length of admin structure */
592 1.17 tls l = offsetof(struct pginfo, bits[0]);
593 1.17 tls l += sizeof bp->bits[0] *
594 1.17 tls (((malloc_pagesize >> bits)+MALLOC_BITS-1) / MALLOC_BITS);
595 1.17 tls
596 1.17 tls /* Don't waste more than two chunks on this */
597 1.17 tls if ((1<<(bits)) <= l+l) {
598 1.17 tls bp = (struct pginfo *)pp;
599 1.17 tls } else {
600 1.31 enami bp = (struct pginfo *)imalloc((size_t)l);
601 1.17 tls if (!bp) {
602 1.17 tls ifree(pp);
603 1.17 tls return 0;
604 1.1 cgd }
605 1.17 tls }
606 1.17 tls
607 1.17 tls bp->size = (1<<bits);
608 1.17 tls bp->shift = bits;
609 1.17 tls bp->total = bp->free = malloc_pagesize >> bits;
610 1.17 tls bp->page = pp;
611 1.17 tls
612 1.17 tls /* set all valid bits in the bitmap */
613 1.17 tls k = bp->total;
614 1.17 tls i = 0;
615 1.17 tls
616 1.17 tls /* Do a bunch at a time */
617 1.17 tls for(;k-i >= MALLOC_BITS; i += MALLOC_BITS)
618 1.30 enami bp->bits[i / MALLOC_BITS] = ~0U;
619 1.17 tls
620 1.17 tls for(; i < k; i++)
621 1.17 tls bp->bits[i/MALLOC_BITS] |= 1<<(i%MALLOC_BITS);
622 1.17 tls
623 1.17 tls if (bp == bp->page) {
624 1.17 tls /* Mark the ones we stole for ourselves */
625 1.17 tls for(i=0;l > 0;i++) {
626 1.17 tls bp->bits[i/MALLOC_BITS] &= ~(1<<(i%MALLOC_BITS));
627 1.17 tls bp->free--;
628 1.17 tls bp->total--;
629 1.17 tls l -= (1 << bits);
630 1.1 cgd }
631 1.17 tls }
632 1.17 tls
633 1.17 tls /* MALLOC_LOCK */
634 1.17 tls
635 1.23 thorpej page_dir[ptr2idx(pp)] = bp;
636 1.17 tls
637 1.17 tls bp->next = page_dir[bits];
638 1.17 tls page_dir[bits] = bp;
639 1.17 tls
640 1.17 tls /* MALLOC_UNLOCK */
641 1.17 tls
642 1.17 tls return 1;
643 1.1 cgd }
644 1.1 cgd
645 1.1 cgd /*
646 1.17 tls * Allocate a fragment
647 1.1 cgd */
648 1.17 tls static void *
649 1.17 tls malloc_bytes(size_t size)
650 1.1 cgd {
651 1.30 enami size_t i;
652 1.30 enami int j;
653 1.17 tls u_int u;
654 1.17 tls struct pginfo *bp;
655 1.17 tls int k;
656 1.17 tls u_int *lp;
657 1.17 tls
658 1.17 tls /* Don't bother with anything less than this */
659 1.17 tls if (size < malloc_minsize)
660 1.17 tls size = malloc_minsize;
661 1.17 tls
662 1.17 tls /* Find the right bucket */
663 1.17 tls j = 1;
664 1.17 tls i = size-1;
665 1.17 tls while (i >>= 1)
666 1.17 tls j++;
667 1.17 tls
668 1.17 tls /* If it's empty, make a page more of that size chunks */
669 1.17 tls if (!page_dir[j] && !malloc_make_chunks(j))
670 1.17 tls return 0;
671 1.17 tls
672 1.17 tls bp = page_dir[j];
673 1.17 tls
674 1.17 tls /* Find first word of bitmap which isn't empty */
675 1.17 tls for (lp = bp->bits; !*lp; lp++)
676 1.17 tls ;
677 1.17 tls
678 1.17 tls /* Find that bit, and tweak it */
679 1.17 tls u = 1;
680 1.17 tls k = 0;
681 1.17 tls while (!(*lp & u)) {
682 1.17 tls u += u;
683 1.17 tls k++;
684 1.17 tls }
685 1.17 tls *lp ^= u;
686 1.17 tls
687 1.17 tls /* If there are no more free, remove from free-list */
688 1.17 tls if (!--bp->free) {
689 1.17 tls page_dir[j] = bp->next;
690 1.17 tls bp->next = 0;
691 1.17 tls }
692 1.17 tls
693 1.17 tls /* Adjust to the real offset of that chunk */
694 1.17 tls k += (lp-bp->bits)*MALLOC_BITS;
695 1.17 tls k <<= bp->shift;
696 1.17 tls
697 1.17 tls if (malloc_junk)
698 1.30 enami memset((u_char*)bp->page + k, SOME_JUNK, (size_t)bp->size);
699 1.1 cgd
700 1.17 tls return (u_char *)bp->page + k;
701 1.1 cgd }
702 1.1 cgd
703 1.17 tls /*
704 1.17 tls * Allocate a piece of memory
705 1.17 tls */
706 1.17 tls static void *
707 1.17 tls imalloc(size_t size)
708 1.17 tls {
709 1.17 tls void *result;
710 1.17 tls
711 1.17 tls if (suicide)
712 1.17 tls abort();
713 1.17 tls
714 1.17 tls if ((size + malloc_pagesize) < size) /* Check for overflow */
715 1.17 tls result = 0;
716 1.17 tls else if (size <= malloc_maxsize)
717 1.17 tls result = malloc_bytes(size);
718 1.17 tls else
719 1.17 tls result = malloc_pages(size);
720 1.17 tls
721 1.17 tls if (malloc_abort && !result)
722 1.17 tls wrterror("allocation failed.\n");
723 1.17 tls
724 1.17 tls if (malloc_zero && result)
725 1.17 tls memset(result, 0, size);
726 1.17 tls
727 1.17 tls return result;
728 1.1 cgd }
729 1.1 cgd
730 1.1 cgd /*
731 1.17 tls * Change the size of an allocation.
732 1.1 cgd */
733 1.17 tls static void *
734 1.17 tls irealloc(void *ptr, size_t size)
735 1.17 tls {
736 1.17 tls void *p;
737 1.30 enami size_t osize, idx;
738 1.17 tls struct pginfo **mp;
739 1.30 enami size_t i;
740 1.17 tls
741 1.17 tls if (suicide)
742 1.17 tls abort();
743 1.17 tls
744 1.23 thorpej idx = ptr2idx(ptr);
745 1.1 cgd
746 1.23 thorpej if (idx < malloc_pageshift) {
747 1.17 tls wrtwarning("junk pointer, too low to make sense.\n");
748 1.17 tls return 0;
749 1.17 tls }
750 1.17 tls
751 1.23 thorpej if (idx > last_idx) {
752 1.17 tls wrtwarning("junk pointer, too high to make sense.\n");
753 1.17 tls return 0;
754 1.17 tls }
755 1.17 tls
756 1.23 thorpej mp = &page_dir[idx];
757 1.17 tls
758 1.17 tls if (*mp == MALLOC_FIRST) { /* Page allocation */
759 1.17 tls
760 1.17 tls /* Check the pointer */
761 1.30 enami if ((size_t)ptr & malloc_pagemask) {
762 1.17 tls wrtwarning("modified (page-) pointer.\n");
763 1.17 tls return 0;
764 1.17 tls }
765 1.17 tls
766 1.17 tls /* Find the size in bytes */
767 1.17 tls for (osize = malloc_pagesize; *++mp == MALLOC_FOLLOW;)
768 1.17 tls osize += malloc_pagesize;
769 1.17 tls
770 1.17 tls if (!malloc_realloc && /* unless we have to, */
771 1.17 tls size <= osize && /* .. or are too small, */
772 1.17 tls size > (osize - malloc_pagesize)) { /* .. or can free a page, */
773 1.17 tls return ptr; /* don't do anything. */
774 1.6 jtc }
775 1.17 tls
776 1.17 tls } else if (*mp >= MALLOC_MAGIC) { /* Chunk allocation */
777 1.17 tls
778 1.17 tls /* Check the pointer for sane values */
779 1.30 enami if (((size_t)ptr & ((*mp)->size-1))) {
780 1.17 tls wrtwarning("modified (chunk-) pointer.\n");
781 1.17 tls return 0;
782 1.1 cgd }
783 1.17 tls
784 1.17 tls /* Find the chunk index in the page */
785 1.30 enami i = ((size_t)ptr & malloc_pagemask) >> (*mp)->shift;
786 1.17 tls
787 1.17 tls /* Verify that it isn't a free chunk already */
788 1.17 tls if ((*mp)->bits[i/MALLOC_BITS] & (1<<(i%MALLOC_BITS))) {
789 1.17 tls wrtwarning("chunk is already free.\n");
790 1.17 tls return 0;
791 1.16 kleink }
792 1.17 tls
793 1.17 tls osize = (*mp)->size;
794 1.17 tls
795 1.17 tls if (!malloc_realloc && /* Unless we have to, */
796 1.17 tls size < osize && /* ..or are too small, */
797 1.17 tls (size > osize/2 || /* ..or could use a smaller size, */
798 1.17 tls osize == malloc_minsize)) { /* ..(if there is one) */
799 1.17 tls return ptr; /* ..Don't do anything */
800 1.1 cgd }
801 1.17 tls
802 1.17 tls } else {
803 1.17 tls wrtwarning("pointer to wrong page.\n");
804 1.17 tls return 0;
805 1.17 tls }
806 1.17 tls
807 1.17 tls p = imalloc(size);
808 1.17 tls
809 1.17 tls if (p) {
810 1.17 tls /* copy the lesser of the two sizes, and free the old one */
811 1.17 tls if (!size || !osize)
812 1.17 tls ;
813 1.17 tls else if (osize < size)
814 1.17 tls memcpy(p, ptr, osize);
815 1.17 tls else
816 1.17 tls memcpy(p, ptr, size);
817 1.17 tls ifree(ptr);
818 1.17 tls }
819 1.17 tls return p;
820 1.1 cgd }
821 1.1 cgd
822 1.1 cgd /*
823 1.17 tls * Free a sequence of pages
824 1.1 cgd */
825 1.17 tls
826 1.17 tls static __inline__ void
827 1.30 enami free_pages(void *ptr, size_t idx, struct pginfo *info)
828 1.17 tls {
829 1.30 enami size_t i;
830 1.17 tls struct pgfree *pf, *pt=0;
831 1.30 enami size_t l;
832 1.17 tls void *tail;
833 1.17 tls
834 1.17 tls if (info == MALLOC_FREE) {
835 1.17 tls wrtwarning("page is already free.\n");
836 1.17 tls return;
837 1.17 tls }
838 1.17 tls
839 1.17 tls if (info != MALLOC_FIRST) {
840 1.17 tls wrtwarning("pointer to wrong page.\n");
841 1.17 tls return;
842 1.17 tls }
843 1.17 tls
844 1.30 enami if ((size_t)ptr & malloc_pagemask) {
845 1.17 tls wrtwarning("modified (page-) pointer.\n");
846 1.17 tls return;
847 1.17 tls }
848 1.17 tls
849 1.17 tls /* Count how many pages and mark them free at the same time */
850 1.23 thorpej page_dir[idx] = MALLOC_FREE;
851 1.23 thorpej for (i = 1; page_dir[idx+i] == MALLOC_FOLLOW; i++)
852 1.23 thorpej page_dir[idx + i] = MALLOC_FREE;
853 1.17 tls
854 1.17 tls l = i << malloc_pageshift;
855 1.17 tls
856 1.17 tls if (malloc_junk)
857 1.17 tls memset(ptr, SOME_JUNK, l);
858 1.17 tls
859 1.17 tls if (malloc_hint)
860 1.17 tls madvise(ptr, l, MADV_FREE);
861 1.17 tls
862 1.17 tls tail = (char *)ptr+l;
863 1.17 tls
864 1.17 tls /* add to free-list */
865 1.17 tls if (!px)
866 1.17 tls px = imalloc(sizeof *pt); /* This cannot fail... */
867 1.17 tls px->page = ptr;
868 1.17 tls px->end = tail;
869 1.17 tls px->size = l;
870 1.17 tls if (!free_list.next) {
871 1.17 tls
872 1.17 tls /* Nothing on free list, put this at head */
873 1.17 tls px->next = free_list.next;
874 1.17 tls px->prev = &free_list;
875 1.17 tls free_list.next = px;
876 1.17 tls pf = px;
877 1.17 tls px = 0;
878 1.17 tls
879 1.17 tls } else {
880 1.17 tls
881 1.17 tls /* Find the right spot, leave pf pointing to the modified entry. */
882 1.17 tls tail = (char *)ptr+l;
883 1.17 tls
884 1.17 tls for(pf = free_list.next; pf->end < ptr && pf->next; pf = pf->next)
885 1.17 tls ; /* Race ahead here */
886 1.17 tls
887 1.17 tls if (pf->page > tail) {
888 1.17 tls /* Insert before entry */
889 1.17 tls px->next = pf;
890 1.17 tls px->prev = pf->prev;
891 1.17 tls pf->prev = px;
892 1.17 tls px->prev->next = px;
893 1.17 tls pf = px;
894 1.17 tls px = 0;
895 1.17 tls } else if (pf->end == ptr ) {
896 1.17 tls /* Append to the previous entry */
897 1.17 tls pf->end = (char *)pf->end + l;
898 1.17 tls pf->size += l;
899 1.17 tls if (pf->next && pf->end == pf->next->page ) {
900 1.17 tls /* And collapse the next too. */
901 1.17 tls pt = pf->next;
902 1.17 tls pf->end = pt->end;
903 1.17 tls pf->size += pt->size;
904 1.17 tls pf->next = pt->next;
905 1.17 tls if (pf->next)
906 1.17 tls pf->next->prev = pf;
907 1.17 tls }
908 1.17 tls } else if (pf->page == tail) {
909 1.17 tls /* Prepend to entry */
910 1.17 tls pf->size += l;
911 1.17 tls pf->page = ptr;
912 1.17 tls } else if (!pf->next) {
913 1.17 tls /* Append at tail of chain */
914 1.17 tls px->next = 0;
915 1.17 tls px->prev = pf;
916 1.17 tls pf->next = px;
917 1.17 tls pf = px;
918 1.17 tls px = 0;
919 1.17 tls } else {
920 1.17 tls wrterror("freelist is destroyed.\n");
921 1.1 cgd }
922 1.17 tls }
923 1.17 tls
924 1.17 tls /* Return something to OS ? */
925 1.17 tls if (!pf->next && /* If we're the last one, */
926 1.17 tls pf->size > malloc_cache && /* ..and the cache is full, */
927 1.17 tls pf->end == malloc_brk && /* ..and none behind us, */
928 1.17 tls malloc_brk == sbrk(0)) { /* ..and it's OK to do... */
929 1.17 tls
930 1.17 tls /*
931 1.17 tls * Keep the cache intact. Notice that the '>' above guarantees that
932 1.17 tls * the pf will always have at least one page afterwards.
933 1.17 tls */
934 1.17 tls pf->end = (char *)pf->page + malloc_cache;
935 1.17 tls pf->size = malloc_cache;
936 1.17 tls
937 1.17 tls brk(pf->end);
938 1.17 tls malloc_brk = pf->end;
939 1.17 tls
940 1.23 thorpej idx = ptr2idx(pf->end);
941 1.23 thorpej last_idx = idx - 1;
942 1.17 tls
943 1.23 thorpej for(i=idx;i <= last_idx;)
944 1.17 tls page_dir[i++] = MALLOC_NOT_MINE;
945 1.17 tls
946 1.17 tls /* XXX: We could realloc/shrink the pagedir here I guess. */
947 1.17 tls }
948 1.17 tls if (pt)
949 1.17 tls ifree(pt);
950 1.1 cgd }
951 1.1 cgd
952 1.1 cgd /*
953 1.17 tls * Free a chunk, and possibly the page it's on, if the page becomes empty.
954 1.1 cgd */
955 1.17 tls
956 1.17 tls static __inline__ void
957 1.30 enami free_bytes(void *ptr, size_t idx, struct pginfo *info)
958 1.17 tls {
959 1.30 enami size_t i;
960 1.17 tls struct pginfo **mp;
961 1.17 tls void *vp;
962 1.17 tls
963 1.17 tls /* Find the chunk number on the page */
964 1.30 enami i = ((size_t)ptr & malloc_pagemask) >> info->shift;
965 1.17 tls
966 1.30 enami if (((size_t)ptr & (info->size-1))) {
967 1.17 tls wrtwarning("modified (chunk-) pointer.\n");
968 1.17 tls return;
969 1.17 tls }
970 1.17 tls
971 1.17 tls if (info->bits[i/MALLOC_BITS] & (1<<(i%MALLOC_BITS))) {
972 1.17 tls wrtwarning("chunk is already free.\n");
973 1.17 tls return;
974 1.17 tls }
975 1.17 tls
976 1.17 tls if (malloc_junk)
977 1.30 enami memset(ptr, SOME_JUNK, (size_t)info->size);
978 1.17 tls
979 1.17 tls info->bits[i/MALLOC_BITS] |= 1<<(i%MALLOC_BITS);
980 1.17 tls info->free++;
981 1.17 tls
982 1.17 tls mp = page_dir + info->shift;
983 1.17 tls
984 1.17 tls if (info->free == 1) {
985 1.17 tls
986 1.17 tls /* Page became non-full */
987 1.17 tls
988 1.17 tls mp = page_dir + info->shift;
989 1.17 tls /* Insert in address order */
990 1.17 tls while (*mp && (*mp)->next && (*mp)->next->page < info->page)
991 1.17 tls mp = &(*mp)->next;
992 1.17 tls info->next = *mp;
993 1.17 tls *mp = info;
994 1.17 tls return;
995 1.17 tls }
996 1.17 tls
997 1.17 tls if (info->free != info->total)
998 1.17 tls return;
999 1.17 tls
1000 1.17 tls /* Find & remove this page in the queue */
1001 1.17 tls while (*mp != info) {
1002 1.17 tls mp = &((*mp)->next);
1003 1.19 thorpej #ifdef MALLOC_EXTRA_SANITY
1004 1.17 tls if (!*mp)
1005 1.17 tls wrterror("(ES): Not on queue\n");
1006 1.19 thorpej #endif /* MALLOC_EXTRA_SANITY */
1007 1.17 tls }
1008 1.17 tls *mp = info->next;
1009 1.17 tls
1010 1.17 tls /* Free the page & the info structure if need be */
1011 1.30 enami page_dir[idx] = MALLOC_FIRST;
1012 1.17 tls vp = info->page; /* Order is important ! */
1013 1.17 tls if(vp != (void*)info)
1014 1.17 tls ifree(info);
1015 1.17 tls ifree(vp);
1016 1.17 tls }
1017 1.17 tls
1018 1.17 tls static void
1019 1.17 tls ifree(void *ptr)
1020 1.17 tls {
1021 1.17 tls struct pginfo *info;
1022 1.30 enami size_t idx;
1023 1.17 tls
1024 1.17 tls /* This is legal */
1025 1.17 tls if (!ptr)
1026 1.17 tls return;
1027 1.17 tls
1028 1.17 tls if (!malloc_started) {
1029 1.17 tls wrtwarning("malloc() has never been called.\n");
1030 1.17 tls return;
1031 1.17 tls }
1032 1.17 tls
1033 1.17 tls /* If we're already sinking, don't make matters any worse. */
1034 1.17 tls if (suicide)
1035 1.17 tls return;
1036 1.17 tls
1037 1.23 thorpej idx = ptr2idx(ptr);
1038 1.17 tls
1039 1.23 thorpej if (idx < malloc_pageshift) {
1040 1.17 tls wrtwarning("junk pointer, too low to make sense.\n");
1041 1.17 tls return;
1042 1.17 tls }
1043 1.17 tls
1044 1.23 thorpej if (idx > last_idx) {
1045 1.17 tls wrtwarning("junk pointer, too high to make sense.\n");
1046 1.17 tls return;
1047 1.17 tls }
1048 1.17 tls
1049 1.23 thorpej info = page_dir[idx];
1050 1.17 tls
1051 1.17 tls if (info < MALLOC_MAGIC)
1052 1.23 thorpej free_pages(ptr, idx, info);
1053 1.17 tls else
1054 1.23 thorpej free_bytes(ptr, idx, info);
1055 1.17 tls return;
1056 1.17 tls }
1057 1.17 tls
1058 1.17 tls /*
1059 1.17 tls * These are the public exported interface routines.
1060 1.17 tls */
1061 1.17 tls
1062 1.17 tls
1063 1.17 tls void *
1064 1.17 tls malloc(size_t size)
1065 1.17 tls {
1066 1.17 tls register void *r;
1067 1.17 tls
1068 1.17 tls THREAD_LOCK();
1069 1.17 tls malloc_func = " in malloc():";
1070 1.17 tls if (malloc_active++) {
1071 1.17 tls wrtwarning("recursive call.\n");
1072 1.17 tls malloc_active--;
1073 1.17 tls return (0);
1074 1.17 tls }
1075 1.17 tls if (!malloc_started)
1076 1.17 tls malloc_init();
1077 1.17 tls if (malloc_sysv && !size)
1078 1.17 tls r = 0;
1079 1.17 tls else
1080 1.17 tls r = imalloc(size);
1081 1.17 tls UTRACE(0, size, r);
1082 1.17 tls malloc_active--;
1083 1.17 tls THREAD_UNLOCK();
1084 1.26 kleink if (r == NULL && (size != 0 || !malloc_sysv)) {
1085 1.24 thorpej if (malloc_xmalloc)
1086 1.24 thorpej wrterror("out of memory.\n");
1087 1.24 thorpej errno = ENOMEM;
1088 1.24 thorpej }
1089 1.17 tls return (r);
1090 1.17 tls }
1091 1.17 tls
1092 1.9 christos void
1093 1.17 tls free(void *ptr)
1094 1.1 cgd {
1095 1.17 tls THREAD_LOCK();
1096 1.17 tls malloc_func = " in free():";
1097 1.17 tls if (malloc_active++) {
1098 1.17 tls wrtwarning("recursive call.\n");
1099 1.17 tls malloc_active--;
1100 1.17 tls return;
1101 1.17 tls } else {
1102 1.17 tls ifree(ptr);
1103 1.17 tls UTRACE(ptr, 0, 0);
1104 1.17 tls }
1105 1.17 tls malloc_active--;
1106 1.17 tls THREAD_UNLOCK();
1107 1.17 tls return;
1108 1.17 tls }
1109 1.17 tls
1110 1.17 tls void *
1111 1.17 tls realloc(void *ptr, size_t size)
1112 1.17 tls {
1113 1.17 tls register void *r;
1114 1.17 tls
1115 1.17 tls THREAD_LOCK();
1116 1.17 tls malloc_func = " in realloc():";
1117 1.17 tls if (malloc_active++) {
1118 1.17 tls wrtwarning("recursive call.\n");
1119 1.17 tls malloc_active--;
1120 1.17 tls return (0);
1121 1.17 tls }
1122 1.17 tls if (ptr && !malloc_started) {
1123 1.17 tls wrtwarning("malloc() has never been called.\n");
1124 1.17 tls ptr = 0;
1125 1.17 tls }
1126 1.17 tls if (!malloc_started)
1127 1.17 tls malloc_init();
1128 1.17 tls if (malloc_sysv && !size) {
1129 1.17 tls ifree(ptr);
1130 1.17 tls r = 0;
1131 1.17 tls } else if (!ptr) {
1132 1.17 tls r = imalloc(size);
1133 1.17 tls } else {
1134 1.17 tls r = irealloc(ptr, size);
1135 1.17 tls }
1136 1.17 tls UTRACE(ptr, size, r);
1137 1.17 tls malloc_active--;
1138 1.17 tls THREAD_UNLOCK();
1139 1.26 kleink if (r == NULL && (size != 0 || !malloc_sysv)) {
1140 1.24 thorpej if (malloc_xmalloc)
1141 1.24 thorpej wrterror("out of memory.\n");
1142 1.24 thorpej errno = ENOMEM;
1143 1.24 thorpej }
1144 1.17 tls return (r);
1145 1.1 cgd }
1146