Commit | Line | Data |
a0d0e21e |
1 | /* malloc.c |
8d063cd8 |
2 | * |
8d063cd8 |
3 | */ |
4 | |
5 | #ifndef lint |
a687059c |
6 | #ifdef DEBUGGING |
8d063cd8 |
7 | #define RCHECK |
a687059c |
8 | #endif |
8d063cd8 |
9 | /* |
10 | * malloc.c (Caltech) 2/21/82 |
11 | * Chris Kingsley, kingsley@cit-20. |
12 | * |
13 | * This is a very fast storage allocator. It allocates blocks of a small |
14 | * number of different sizes, and keeps free lists of each size. Blocks that |
15 | * don't exactly fit are passed up to the next larger size. In this |
16 | * implementation, the available sizes are 2^n-4 (or 2^n-12) bytes long. |
cf5c4ad8 |
17 | * If PACK_MALLOC is defined, small blocks are 2^n bytes long. |
8d063cd8 |
18 | * This is designed for use in a program that uses vast quantities of memory, |
19 | * but bombs when it runs out. |
20 | */ |
21 | |
135863df |
22 | #include "EXTERN.h" |
135863df |
23 | #include "perl.h" |
24 | |
760ac839 |
25 | #ifdef DEBUGGING |
26 | #undef DEBUG_m |
27 | #define DEBUG_m(a) if (debug & 128) a |
28 | #endif |
29 | |
135863df |
30 | /* I don't much care whether these are defined in sys/types.h--LAW */ |
31 | |
32 | #define u_char unsigned char |
33 | #define u_int unsigned int |
34 | #define u_short unsigned short |
8d063cd8 |
35 | |
cf5c4ad8 |
36 | /* 286 and atarist like big chunks, which gives too much overhead. */ |
37 | #if (defined(RCHECK) || defined(I286) || defined(atarist)) && defined(PACK_MALLOC) |
38 | #undef PACK_MALLOC |
39 | #endif |
40 | |
41 | |
8d063cd8 |
42 | /* |
cf5c4ad8 |
43 | * The description below is applicable if PACK_MALLOC is not defined. |
44 | * |
8d063cd8 |
45 | * The overhead on a block is at least 4 bytes. When free, this space |
46 | * contains a pointer to the next free block, and the bottom two bits must |
47 | * be zero. When in use, the first byte is set to MAGIC, and the second |
48 | * byte is the size index. The remaining bytes are for alignment. |
49 | * If range checking is enabled and the size of the block fits |
50 | * in two bytes, then the top two bytes hold the size of the requested block |
51 | * plus the range checking words, and the header word MINUS ONE. |
52 | */ |
53 | union overhead { |
54 | union overhead *ov_next; /* when free */ |
85e6fe83 |
55 | #if MEM_ALIGNBYTES > 4 |
c623bd54 |
56 | double strut; /* alignment problems */ |
a687059c |
57 | #endif |
8d063cd8 |
58 | struct { |
59 | u_char ovu_magic; /* magic number */ |
60 | u_char ovu_index; /* bucket # */ |
61 | #ifdef RCHECK |
62 | u_short ovu_size; /* actual block size */ |
63 | u_int ovu_rmagic; /* range magic number */ |
64 | #endif |
65 | } ovu; |
66 | #define ov_magic ovu.ovu_magic |
67 | #define ov_index ovu.ovu_index |
68 | #define ov_size ovu.ovu_size |
69 | #define ov_rmagic ovu.ovu_rmagic |
70 | }; |
71 | |
760ac839 |
72 | #ifdef DEBUGGING |
a0d0e21e |
73 | static void botch _((char *s)); |
74 | #endif |
75 | static void morecore _((int bucket)); |
76 | static int findbucket _((union overhead *freep, int srchlen)); |
77 | |
8d063cd8 |
78 | #define MAGIC 0xff /* magic # on accounting info */ |
79 | #define RMAGIC 0x55555555 /* magic # on range info */ |
80 | #ifdef RCHECK |
81 | #define RSLOP sizeof (u_int) |
82 | #else |
83 | #define RSLOP 0 |
84 | #endif |
85 | |
cf5c4ad8 |
86 | #ifdef PACK_MALLOC |
87 | /* |
88 | * In this case it is assumed that if we do sbrk() in 2K units, we |
89 | * will get 2K aligned blocks. The bucket number of the given subblock is |
90 | * on the boundary of 2K block which contains the subblock. |
91 | * Several following bytes contain the magic numbers for the subblocks |
92 | * in the block. |
93 | * |
94 | * Sizes of chunks are powers of 2 for chunks in buckets <= |
95 | * MAX_PACKED, after this they are (2^n - sizeof(union overhead)) (to |
96 | * get alignment right). |
97 | * |
98 | * We suppose that starts of all the chunks in a 2K block are in |
99 | * different 2^n-byte-long chunks. If the top of the last chunk is |
100 | * aligned on a boundary of 2K block, this means that |
101 | * sizeof(union overhead)*"number of chunks" < 2^n, or |
102 | * sizeof(union overhead)*2K < 4^n, or n > 6 + log2(sizeof()/2)/2, if a |
103 | * chunk of size 2^n - overhead is used. Since this rules out n = 7 |
104 | * for 8 byte alignment, we specialcase allocation of the first of 16 |
105 | * 128-byte-long chunks. |
106 | * |
107 | * Note that with the above assumption we automatically have enough |
108 | * place for MAGIC at the start of 2K block. Note also that we |
109 | * overlay union overhead over the chunk, thus the start of the chunk |
110 | * is immediately overwritten after freeing. |
111 | */ |
112 | # define MAX_PACKED 6 |
113 | # define MAX_2_POT_ALGO ((1<<(MAX_PACKED + 1)) - M_OVERHEAD) |
114 | # define TWOK_MASK ((1<<11) - 1) |
115 | # define TWOK_MASKED(x) ((int)x & ~TWOK_MASK) |
116 | # define TWOK_SHIFT(x) ((int)x & TWOK_MASK) |
117 | # define OV_INDEXp(block) ((u_char*)(TWOK_MASKED(block))) |
118 | # define OV_INDEX(block) (*OV_INDEXp(block)) |
119 | # define OV_MAGIC(block,bucket) (*(OV_INDEXp(block) + \ |
120 | (TWOK_SHIFT(block)>>(bucket + 3)) + \ |
121 | (bucket > MAX_NONSHIFT ? 1 : 0))) |
122 | # define CHUNK_SHIFT 0 |
123 | |
124 | static u_char n_blks[11 - 3] = {224, 120, 62, 31, 16, 8, 4, 2}; |
125 | static u_short blk_shift[11 - 3] = {256, 128, 64, 32, |
126 | 16*sizeof(union overhead), |
127 | 8*sizeof(union overhead), |
128 | 4*sizeof(union overhead), |
129 | 2*sizeof(union overhead), |
130 | # define MAX_NONSHIFT 2 /* Shift 64 greater than chunk 32. */ |
131 | }; |
132 | |
133 | # ifdef DEBUGGING_MSTATS |
134 | static u_int sbrk_slack; |
135 | static u_int start_slack; |
136 | # endif |
137 | |
138 | #else /* !PACK_MALLOC */ |
139 | |
140 | # define OV_MAGIC(block,bucket) (block)->ov_magic |
141 | # define OV_INDEX(block) (block)->ov_index |
142 | # define CHUNK_SHIFT 1 |
143 | #endif /* !PACK_MALLOC */ |
144 | |
145 | # define M_OVERHEAD (sizeof(union overhead) + RSLOP) |
146 | |
8d063cd8 |
147 | /* |
148 | * nextf[i] is the pointer to the next free block of size 2^(i+3). The |
149 | * smallest allocatable block is 8 bytes. The overhead information |
150 | * precedes the data area returned to the user. |
151 | */ |
152 | #define NBUCKETS 30 |
153 | static union overhead *nextf[NBUCKETS]; |
cf5c4ad8 |
154 | |
155 | #ifdef USE_PERL_SBRK |
156 | #define sbrk(a) Perl_sbrk(a) |
157 | char * Perl_sbrk _((int size)); |
158 | #else |
8d063cd8 |
159 | extern char *sbrk(); |
cf5c4ad8 |
160 | #endif |
8d063cd8 |
161 | |
c07a80fd |
162 | #ifdef DEBUGGING_MSTATS |
8d063cd8 |
163 | /* |
164 | * nmalloc[i] is the difference between the number of mallocs and frees |
165 | * for a given block size. |
166 | */ |
167 | static u_int nmalloc[NBUCKETS]; |
8d063cd8 |
168 | #endif |
169 | |
760ac839 |
170 | #ifdef DEBUGGING |
4dfc412b |
171 | #define ASSERT(p) if (!(p)) botch(STRINGIFY(p)); else |
ee0007ab |
172 | static void |
8d063cd8 |
173 | botch(s) |
174 | char *s; |
175 | { |
4dfc412b |
176 | PerlIO_printf(PerlIO_stderr(), "assertion botched: %s\n", s); |
8d063cd8 |
177 | abort(); |
178 | } |
179 | #else |
180 | #define ASSERT(p) |
181 | #endif |
182 | |
2304df62 |
183 | Malloc_t |
8d063cd8 |
184 | malloc(nbytes) |
ee0007ab |
185 | register MEM_SIZE nbytes; |
8d063cd8 |
186 | { |
187 | register union overhead *p; |
188 | register int bucket = 0; |
ee0007ab |
189 | register MEM_SIZE shiftr; |
8d063cd8 |
190 | |
45d8adaa |
191 | #ifdef safemalloc |
192 | #ifdef DEBUGGING |
ee0007ab |
193 | MEM_SIZE size = nbytes; |
45d8adaa |
194 | #endif |
195 | |
196 | #ifdef MSDOS |
197 | if (nbytes > 0xffff) { |
760ac839 |
198 | PerlIO_printf(PerlIO_stderr(), "Allocation too large: %lx\n", (long)nbytes); |
79072805 |
199 | my_exit(1); |
45d8adaa |
200 | } |
201 | #endif /* MSDOS */ |
202 | #ifdef DEBUGGING |
203 | if ((long)nbytes < 0) |
463ee0b2 |
204 | croak("panic: malloc"); |
45d8adaa |
205 | #endif |
206 | #endif /* safemalloc */ |
207 | |
8d063cd8 |
208 | /* |
209 | * Convert amount of memory requested into |
210 | * closest block size stored in hash buckets |
211 | * which satisfies request. Account for |
212 | * space used per block for accounting. |
213 | */ |
cf5c4ad8 |
214 | #ifdef PACK_MALLOC |
215 | if (nbytes > MAX_2_POT_ALGO) { |
216 | #endif |
217 | nbytes += M_OVERHEAD; |
218 | nbytes = (nbytes + 3) &~ 3; |
219 | #ifdef PACK_MALLOC |
220 | } else if (nbytes == 0) { |
221 | nbytes = 1; |
222 | } |
223 | #endif |
8d063cd8 |
224 | shiftr = (nbytes - 1) >> 2; |
225 | /* apart from this loop, this is O(1) */ |
226 | while (shiftr >>= 1) |
227 | bucket++; |
228 | /* |
229 | * If nothing in hash bucket right now, |
230 | * request more memory from the system. |
231 | */ |
232 | if (nextf[bucket] == NULL) |
233 | morecore(bucket); |
45d8adaa |
234 | if ((p = (union overhead *)nextf[bucket]) == NULL) { |
235 | #ifdef safemalloc |
ee0007ab |
236 | if (!nomemok) { |
760ac839 |
237 | PerlIO_puts(PerlIO_stderr(),"Out of memory!\n"); |
79072805 |
238 | my_exit(1); |
ee0007ab |
239 | } |
45d8adaa |
240 | #else |
8d063cd8 |
241 | return (NULL); |
45d8adaa |
242 | #endif |
243 | } |
244 | |
245 | #ifdef safemalloc |
760ac839 |
246 | DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%lx: (%05d) malloc %ld bytes\n", |
a0d0e21e |
247 | (unsigned long)(p+1),an++,(long)size)); |
45d8adaa |
248 | #endif /* safemalloc */ |
249 | |
8d063cd8 |
250 | /* remove from linked list */ |
bf38876a |
251 | #ifdef RCHECK |
252 | if (*((int*)p) & (sizeof(union overhead) - 1)) |
760ac839 |
253 | PerlIO_printf(PerlIO_stderr(), "Corrupt malloc ptr 0x%lx at 0x%lx\n", |
a0d0e21e |
254 | (unsigned long)*((int*)p),(unsigned long)p); |
bf38876a |
255 | #endif |
256 | nextf[bucket] = p->ov_next; |
cf5c4ad8 |
257 | OV_MAGIC(p, bucket) = MAGIC; |
258 | #ifndef PACK_MALLOC |
259 | OV_INDEX(p) = bucket; |
260 | #endif |
c07a80fd |
261 | #ifdef DEBUGGING_MSTATS |
8d063cd8 |
262 | nmalloc[bucket]++; |
263 | #endif |
264 | #ifdef RCHECK |
265 | /* |
266 | * Record allocated size of block and |
267 | * bound space with magic numbers. |
268 | */ |
269 | if (nbytes <= 0x10000) |
270 | p->ov_size = nbytes - 1; |
271 | p->ov_rmagic = RMAGIC; |
272 | *((u_int *)((caddr_t)p + nbytes - RSLOP)) = RMAGIC; |
273 | #endif |
cf5c4ad8 |
274 | return ((Malloc_t)(p + CHUNK_SHIFT)); |
8d063cd8 |
275 | } |
276 | |
277 | /* |
278 | * Allocate more memory to the indicated bucket. |
279 | */ |
a0d0e21e |
280 | static void |
8d063cd8 |
281 | morecore(bucket) |
a687059c |
282 | register int bucket; |
8d063cd8 |
283 | { |
284 | register union overhead *op; |
285 | register int rnu; /* 2^rnu bytes will be requested */ |
286 | register int nblks; /* become nblks blocks of the desired size */ |
ee0007ab |
287 | register MEM_SIZE siz; |
cf5c4ad8 |
288 | int slack = 0; |
8d063cd8 |
289 | |
290 | if (nextf[bucket]) |
291 | return; |
292 | /* |
293 | * Insure memory is allocated |
294 | * on a page boundary. Should |
295 | * make getpageize call? |
296 | */ |
ee0007ab |
297 | #ifndef atarist /* on the atari we dont have to worry about this */ |
8d063cd8 |
298 | op = (union overhead *)sbrk(0); |
cf5c4ad8 |
299 | # ifndef I286 |
300 | # ifdef PACK_MALLOC |
301 | if ((int)op & 0x7ff) |
302 | (void)sbrk(slack = 2048 - ((int)op & 0x7ff)); |
303 | # else |
8d063cd8 |
304 | if ((int)op & 0x3ff) |
cf5c4ad8 |
305 | (void)sbrk(slack = 1024 - ((int)op & 0x3ff)); |
306 | # endif |
307 | # if defined(DEBUGGING_MSTATS) && defined(PACK_MALLOC) |
308 | sbrk_slack += slack; |
309 | # endif |
310 | # else |
a687059c |
311 | /* The sbrk(0) call on the I286 always returns the next segment */ |
cf5c4ad8 |
312 | # endif |
ee0007ab |
313 | #endif /* atarist */ |
a687059c |
314 | |
ee0007ab |
315 | #if !(defined(I286) || defined(atarist)) |
8d063cd8 |
316 | /* take 2k unless the block is bigger than that */ |
317 | rnu = (bucket <= 8) ? 11 : bucket + 3; |
a687059c |
318 | #else |
319 | /* take 16k unless the block is bigger than that |
ee0007ab |
320 | (80286s like large segments!), probably good on the atari too */ |
a687059c |
321 | rnu = (bucket <= 11) ? 14 : bucket + 3; |
322 | #endif |
8d063cd8 |
323 | nblks = 1 << (rnu - (bucket + 3)); /* how many blocks to get */ |
cf5c4ad8 |
324 | /* if (rnu < bucket) |
325 | rnu = bucket; Why anyone needs this? */ |
ee0007ab |
326 | op = (union overhead *)sbrk(1L << rnu); |
8d063cd8 |
327 | /* no more room! */ |
328 | if ((int)op == -1) |
329 | return; |
330 | /* |
331 | * Round up to minimum allocation size boundary |
332 | * and deduct from block count to reflect. |
333 | */ |
a687059c |
334 | #ifndef I286 |
cf5c4ad8 |
335 | # ifdef PACK_MALLOC |
336 | if ((int)op & 0x7ff) |
337 | croak("panic: Off-page sbrk"); |
338 | # endif |
8d063cd8 |
339 | if ((int)op & 7) { |
ee0007ab |
340 | op = (union overhead *)(((MEM_SIZE)op + 8) &~ 7); |
8d063cd8 |
341 | nblks--; |
342 | } |
a687059c |
343 | #else |
344 | /* Again, this should always be ok on an 80286 */ |
345 | #endif |
8d063cd8 |
346 | /* |
347 | * Add new memory allocated to that on |
348 | * free list for this hash bucket. |
349 | */ |
8d063cd8 |
350 | siz = 1 << (bucket + 3); |
cf5c4ad8 |
351 | #ifdef PACK_MALLOC |
352 | *(u_char*)op = bucket; /* Fill index. */ |
353 | if (bucket <= MAX_PACKED - 3) { |
354 | op = (union overhead *) ((char*)op + blk_shift[bucket]); |
355 | nblks = n_blks[bucket]; |
356 | # ifdef DEBUGGING_MSTATS |
357 | start_slack += blk_shift[bucket]; |
358 | # endif |
359 | } else if (bucket <= 11 - 1 - 3) { |
360 | op = (union overhead *) ((char*)op + blk_shift[bucket]); |
361 | /* nblks = n_blks[bucket]; */ |
362 | siz -= sizeof(union overhead); |
363 | } else op++; /* One chunk per block. */ |
364 | #endif /* !PACK_MALLOC */ |
365 | nextf[bucket] = op; |
8d063cd8 |
366 | while (--nblks > 0) { |
367 | op->ov_next = (union overhead *)((caddr_t)op + siz); |
368 | op = (union overhead *)((caddr_t)op + siz); |
369 | } |
8595d6f1 |
370 | /* Not all sbrks return zeroed memory.*/ |
cf5c4ad8 |
371 | op->ov_next = (union overhead *)NULL; |
cf5c4ad8 |
372 | #ifdef PACK_MALLOC |
373 | if (bucket == 7 - 3) { /* Special case, explanation is above. */ |
374 | union overhead *n_op = nextf[7 - 3]->ov_next; |
375 | nextf[7 - 3] = (union overhead *)((caddr_t)nextf[7 - 3] |
376 | - sizeof(union overhead)); |
377 | nextf[7 - 3]->ov_next = n_op; |
378 | } |
379 | #endif /* !PACK_MALLOC */ |
8d063cd8 |
380 | } |
381 | |
94b6baf5 |
382 | Free_t |
352d5a3a |
383 | free(mp) |
2304df62 |
384 | Malloc_t mp; |
8d063cd8 |
385 | { |
ee0007ab |
386 | register MEM_SIZE size; |
8d063cd8 |
387 | register union overhead *op; |
352d5a3a |
388 | char *cp = (char*)mp; |
cf5c4ad8 |
389 | #ifdef PACK_MALLOC |
390 | u_char bucket; |
391 | #endif |
8d063cd8 |
392 | |
45d8adaa |
393 | #ifdef safemalloc |
760ac839 |
394 | DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%lx: (%05d) free\n",(unsigned long)cp,an++)); |
45d8adaa |
395 | #endif /* safemalloc */ |
396 | |
cf5c4ad8 |
397 | if (cp == NULL) |
398 | return; |
399 | op = (union overhead *)((caddr_t)cp |
400 | - sizeof (union overhead) * CHUNK_SHIFT); |
401 | #ifdef PACK_MALLOC |
402 | bucket = OV_INDEX(op); |
403 | #endif |
760ac839 |
404 | #ifdef DEBUGGING |
cf5c4ad8 |
405 | ASSERT(OV_MAGIC(op, bucket) == MAGIC); /* make sure it was in use */ |
8d063cd8 |
406 | #else |
cf5c4ad8 |
407 | if (OV_MAGIC(op, bucket) != MAGIC) { |
408 | static bad_free_warn = -1; |
409 | if (bad_free_warn == -1) { |
410 | char *pbf = getenv("PERL_BADFREE"); |
411 | bad_free_warn = (pbf) ? atoi(pbf) : 1; |
412 | } |
413 | if (!bad_free_warn) |
414 | return; |
8990e307 |
415 | #ifdef RCHECK |
a687059c |
416 | warn("%s free() ignored", |
8990e307 |
417 | op->ov_rmagic == RMAGIC - 1 ? "Duplicate" : "Bad"); |
418 | #else |
419 | warn("Bad free() ignored"); |
420 | #endif |
8d063cd8 |
421 | return; /* sanity */ |
378cc40b |
422 | } |
8d063cd8 |
423 | #endif |
424 | #ifdef RCHECK |
425 | ASSERT(op->ov_rmagic == RMAGIC); |
cf5c4ad8 |
426 | if (OV_INDEX(op) <= 13) |
8d063cd8 |
427 | ASSERT(*(u_int *)((caddr_t)op + op->ov_size + 1 - RSLOP) == RMAGIC); |
8990e307 |
428 | op->ov_rmagic = RMAGIC - 1; |
8d063cd8 |
429 | #endif |
cf5c4ad8 |
430 | ASSERT(OV_INDEX(op) < NBUCKETS); |
431 | size = OV_INDEX(op); |
8d063cd8 |
432 | op->ov_next = nextf[size]; |
433 | nextf[size] = op; |
c07a80fd |
434 | #ifdef DEBUGGING_MSTATS |
8d063cd8 |
435 | nmalloc[size]--; |
436 | #endif |
437 | } |
438 | |
439 | /* |
440 | * When a program attempts "storage compaction" as mentioned in the |
441 | * old malloc man page, it realloc's an already freed block. Usually |
442 | * this is the last block it freed; occasionally it might be farther |
443 | * back. We have to search all the free lists for the block in order |
444 | * to determine its bucket: 1st we make one pass thru the lists |
445 | * checking only the first block in each; if that fails we search |
378cc40b |
446 | * ``reall_srchlen'' blocks in each list for a match (the variable |
8d063cd8 |
447 | * is extern so the caller can modify it). If that fails we just copy |
448 | * however many bytes was given to realloc() and hope it's not huge. |
449 | */ |
378cc40b |
450 | int reall_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */ |
8d063cd8 |
451 | |
2304df62 |
452 | Malloc_t |
352d5a3a |
453 | realloc(mp, nbytes) |
2304df62 |
454 | Malloc_t mp; |
ee0007ab |
455 | MEM_SIZE nbytes; |
8d063cd8 |
456 | { |
ee0007ab |
457 | register MEM_SIZE onb; |
8d063cd8 |
458 | union overhead *op; |
459 | char *res; |
460 | register int i; |
461 | int was_alloced = 0; |
352d5a3a |
462 | char *cp = (char*)mp; |
8d063cd8 |
463 | |
45d8adaa |
464 | #ifdef safemalloc |
465 | #ifdef DEBUGGING |
ee0007ab |
466 | MEM_SIZE size = nbytes; |
45d8adaa |
467 | #endif |
468 | |
469 | #ifdef MSDOS |
470 | if (nbytes > 0xffff) { |
760ac839 |
471 | PerlIO_printf(PerlIO_stderr(), "Reallocation too large: %lx\n", size); |
79072805 |
472 | my_exit(1); |
45d8adaa |
473 | } |
474 | #endif /* MSDOS */ |
475 | if (!cp) |
ee0007ab |
476 | return malloc(nbytes); |
45d8adaa |
477 | #ifdef DEBUGGING |
478 | if ((long)nbytes < 0) |
463ee0b2 |
479 | croak("panic: realloc"); |
45d8adaa |
480 | #endif |
481 | #endif /* safemalloc */ |
482 | |
cf5c4ad8 |
483 | op = (union overhead *)((caddr_t)cp |
484 | - sizeof (union overhead) * CHUNK_SHIFT); |
485 | i = OV_INDEX(op); |
486 | if (OV_MAGIC(op, i) == MAGIC) { |
8d063cd8 |
487 | was_alloced++; |
8d063cd8 |
488 | } else { |
489 | /* |
490 | * Already free, doing "compaction". |
491 | * |
492 | * Search for the old block of memory on the |
493 | * free list. First, check the most common |
494 | * case (last element free'd), then (this failing) |
378cc40b |
495 | * the last ``reall_srchlen'' items free'd. |
8d063cd8 |
496 | * If all lookups fail, then assume the size of |
497 | * the memory block being realloc'd is the |
498 | * smallest possible. |
499 | */ |
500 | if ((i = findbucket(op, 1)) < 0 && |
378cc40b |
501 | (i = findbucket(op, reall_srchlen)) < 0) |
8d063cd8 |
502 | i = 0; |
503 | } |
cf5c4ad8 |
504 | onb = (1L << (i + 3)) - |
505 | #ifdef PACK_MALLOC |
506 | (i <= (MAX_PACKED - 3) ? 0 : M_OVERHEAD) |
507 | #else |
508 | M_OVERHEAD |
509 | #endif |
510 | ; |
8d063cd8 |
511 | /* avoid the copy if same size block */ |
512 | if (was_alloced && |
cf5c4ad8 |
513 | nbytes <= onb && nbytes > (onb >> 1) - M_OVERHEAD) { |
a687059c |
514 | #ifdef RCHECK |
515 | /* |
516 | * Record new allocated size of block and |
517 | * bound space with magic numbers. |
518 | */ |
cf5c4ad8 |
519 | if (OV_INDEX(op) <= 13) { |
a687059c |
520 | /* |
521 | * Convert amount of memory requested into |
522 | * closest block size stored in hash buckets |
523 | * which satisfies request. Account for |
524 | * space used per block for accounting. |
525 | */ |
cf5c4ad8 |
526 | nbytes += M_OVERHEAD; |
a687059c |
527 | nbytes = (nbytes + 3) &~ 3; |
528 | op->ov_size = nbytes - 1; |
529 | *((u_int *)((caddr_t)op + nbytes - RSLOP)) = RMAGIC; |
530 | } |
531 | #endif |
45d8adaa |
532 | res = cp; |
a687059c |
533 | } |
45d8adaa |
534 | else { |
535 | if ((res = (char*)malloc(nbytes)) == NULL) |
536 | return (NULL); |
537 | if (cp != res) /* common optimization */ |
ee0007ab |
538 | Copy(cp, res, (MEM_SIZE)(nbytes<onb?nbytes:onb), char); |
45d8adaa |
539 | if (was_alloced) |
540 | free(cp); |
541 | } |
542 | |
543 | #ifdef safemalloc |
544 | #ifdef DEBUGGING |
a0d0e21e |
545 | if (debug & 128) { |
760ac839 |
546 | PerlIO_printf(PerlIO_stderr(), "0x%lx: (%05d) rfree\n",(unsigned long)res,an++); |
547 | PerlIO_printf(PerlIO_stderr(), "0x%lx: (%05d) realloc %ld bytes\n", |
a0d0e21e |
548 | (unsigned long)res,an++,(long)size); |
549 | } |
45d8adaa |
550 | #endif |
551 | #endif /* safemalloc */ |
2304df62 |
552 | return ((Malloc_t)res); |
8d063cd8 |
553 | } |
554 | |
555 | /* |
556 | * Search ``srchlen'' elements of each free list for a block whose |
557 | * header starts at ``freep''. If srchlen is -1 search the whole list. |
558 | * Return bucket number, or -1 if not found. |
559 | */ |
ee0007ab |
560 | static int |
8d063cd8 |
561 | findbucket(freep, srchlen) |
562 | union overhead *freep; |
563 | int srchlen; |
564 | { |
565 | register union overhead *p; |
566 | register int i, j; |
567 | |
568 | for (i = 0; i < NBUCKETS; i++) { |
569 | j = 0; |
570 | for (p = nextf[i]; p && j != srchlen; p = p->ov_next) { |
571 | if (p == freep) |
572 | return (i); |
573 | j++; |
574 | } |
575 | } |
576 | return (-1); |
577 | } |
578 | |
cf5c4ad8 |
579 | Malloc_t |
580 | calloc(elements, size) |
581 | register MEM_SIZE elements; |
582 | register MEM_SIZE size; |
583 | { |
584 | long sz = elements * size; |
585 | Malloc_t p = malloc(sz); |
586 | |
587 | if (p) { |
588 | memset((void*)p, 0, sz); |
589 | } |
590 | return p; |
591 | } |
592 | |
c07a80fd |
593 | #ifdef DEBUGGING_MSTATS |
8d063cd8 |
594 | /* |
595 | * mstats - print out statistics about malloc |
596 | * |
597 | * Prints two lines of numbers, one showing the length of the free list |
598 | * for each size category, the second showing the number of mallocs - |
599 | * frees for each size category. |
600 | */ |
ee0007ab |
601 | void |
c07a80fd |
602 | dump_mstats(s) |
8d063cd8 |
603 | char *s; |
604 | { |
605 | register int i, j; |
606 | register union overhead *p; |
c07a80fd |
607 | int topbucket=0, totfree=0, totused=0; |
608 | u_int nfree[NBUCKETS]; |
8d063cd8 |
609 | |
c07a80fd |
610 | for (i=0; i < NBUCKETS; i++) { |
8d063cd8 |
611 | for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) |
612 | ; |
c07a80fd |
613 | nfree[i] = j; |
614 | totfree += nfree[i] * (1 << (i + 3)); |
8d063cd8 |
615 | totused += nmalloc[i] * (1 << (i + 3)); |
c07a80fd |
616 | if (nfree[i] || nmalloc[i]) |
617 | topbucket = i; |
618 | } |
619 | if (s) |
760ac839 |
620 | PerlIO_printf(PerlIO_stderr(), "Memory allocation statistics %s (buckets 8..%d)\n", |
c07a80fd |
621 | s, (1 << (topbucket + 3)) ); |
760ac839 |
622 | PerlIO_printf(PerlIO_stderr(), " %7d free: ", totfree); |
c07a80fd |
623 | for (i=0; i <= topbucket; i++) { |
760ac839 |
624 | PerlIO_printf(PerlIO_stderr(), (i<5)?" %5d":" %3d", nfree[i]); |
8d063cd8 |
625 | } |
760ac839 |
626 | PerlIO_printf(PerlIO_stderr(), "\n %7d used: ", totused); |
c07a80fd |
627 | for (i=0; i <= topbucket; i++) { |
760ac839 |
628 | PerlIO_printf(PerlIO_stderr(), (i<5)?" %5d":" %3d", nmalloc[i]); |
c07a80fd |
629 | } |
760ac839 |
630 | PerlIO_printf(PerlIO_stderr(), "\n"); |
cf5c4ad8 |
631 | #ifdef PACK_MALLOC |
632 | if (sbrk_slack || start_slack) { |
760ac839 |
633 | PerlIO_printf(PerlIO_stderr(), "Odd ends: %7d bytes from sbrk(), %7d from malloc.\n", |
cf5c4ad8 |
634 | sbrk_slack, start_slack); |
635 | } |
636 | #endif |
c07a80fd |
637 | } |
638 | #else |
639 | void |
640 | dump_mstats(s) |
641 | char *s; |
642 | { |
8d063cd8 |
643 | } |
644 | #endif |
a687059c |
645 | #endif /* lint */ |
cf5c4ad8 |
646 | |
647 | |
648 | #ifdef USE_PERL_SBRK |
649 | |
760ac839 |
650 | # ifdef NeXT |
651 | # define PERL_SBRK_VIA_MALLOC |
652 | # endif |
653 | |
654 | # ifdef PERL_SBRK_VIA_MALLOC |
655 | # ifdef HIDEMYMALLOC |
656 | # undef malloc |
657 | # else |
658 | # include "Error: -DPERL_SBRK_VIA_MALLOC requires -DHIDEMYMALLOC" |
659 | # endif |
cf5c4ad8 |
660 | |
661 | /* it may seem schizophrenic to use perl's malloc and let it call system */ |
662 | /* malloc, the reason for that is only the 3.2 version of the OS that had */ |
663 | /* frequent core dumps within nxzonefreenolock. This sbrk routine put an */ |
664 | /* end to the cores */ |
665 | |
760ac839 |
666 | # define SYSTEM_ALLOC(a) malloc(a) |
cf5c4ad8 |
667 | |
760ac839 |
668 | # endif /* PERL_SBRK_VIA_MALLOC */ |
cf5c4ad8 |
669 | |
670 | static IV Perl_sbrk_oldchunk; |
671 | static long Perl_sbrk_oldsize; |
672 | |
760ac839 |
673 | # define PERLSBRK_32_K (1<<15) |
674 | # define PERLSBRK_64_K (1<<16) |
cf5c4ad8 |
675 | |
676 | char * |
677 | Perl_sbrk(size) |
678 | int size; |
679 | { |
680 | IV got; |
681 | int small, reqsize; |
682 | |
683 | if (!size) return 0; |
684 | #ifdef safemalloc |
685 | reqsize = size; /* just for the DEBUG_m statement */ |
686 | #endif |
687 | if (size <= Perl_sbrk_oldsize) { |
688 | got = Perl_sbrk_oldchunk; |
689 | Perl_sbrk_oldchunk += size; |
690 | Perl_sbrk_oldsize -= size; |
691 | } else { |
692 | if (size >= PERLSBRK_32_K) { |
693 | small = 0; |
694 | } else { |
695 | #ifndef safemalloc |
696 | reqsize = size; |
697 | #endif |
698 | size = PERLSBRK_64_K; |
699 | small = 1; |
700 | } |
701 | got = (IV)SYSTEM_ALLOC(size); |
702 | if (small) { |
703 | /* Chunk is small, register the rest for future allocs. */ |
704 | Perl_sbrk_oldchunk = got + reqsize; |
705 | Perl_sbrk_oldsize = size - reqsize; |
706 | } |
707 | } |
708 | |
709 | #ifdef safemalloc |
760ac839 |
710 | DEBUG_m(PerlIO_printf(PerlIO_stderr(), "sbrk malloc size %ld (reqsize %ld), left size %ld, give addr 0x%lx\n", |
cf5c4ad8 |
711 | size, reqsize, Perl_sbrk_oldsize, got)); |
712 | #endif |
713 | |
714 | return (void *)got; |
715 | } |
716 | |
717 | #endif /* ! defined USE_PERL_SBRK */ |