Commit | Line | Data |
a0d0e21e |
1 | /* malloc.c |
8d063cd8 |
2 | * |
8d063cd8 |
3 | */ |
4 | |
5 | #ifndef lint |
1944739a |
6 | # if defined(DEBUGGING) && !defined(NO_RCHECK) |
7 | # define RCHECK |
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 |
c2a5c2d2 |
81 | # define RSLOP sizeof (u_int) |
82 | # ifdef TWO_POT_OPTIMIZE |
83 | # define MAX_SHORT_BUCKET 12 |
84 | # else |
85 | # define MAX_SHORT_BUCKET 13 |
86 | # endif |
8d063cd8 |
87 | #else |
c2a5c2d2 |
88 | # define RSLOP 0 |
8d063cd8 |
89 | #endif |
90 | |
cf5c4ad8 |
91 | #ifdef PACK_MALLOC |
92 | /* |
93 | * In this case it is assumed that if we do sbrk() in 2K units, we |
94 | * will get 2K aligned blocks. The bucket number of the given subblock is |
95 | * on the boundary of 2K block which contains the subblock. |
96 | * Several following bytes contain the magic numbers for the subblocks |
97 | * in the block. |
98 | * |
99 | * Sizes of chunks are powers of 2 for chunks in buckets <= |
100 | * MAX_PACKED, after this they are (2^n - sizeof(union overhead)) (to |
101 | * get alignment right). |
102 | * |
103 | * We suppose that starts of all the chunks in a 2K block are in |
104 | * different 2^n-byte-long chunks. If the top of the last chunk is |
105 | * aligned on a boundary of 2K block, this means that |
106 | * sizeof(union overhead)*"number of chunks" < 2^n, or |
107 | * sizeof(union overhead)*2K < 4^n, or n > 6 + log2(sizeof()/2)/2, if a |
108 | * chunk of size 2^n - overhead is used. Since this rules out n = 7 |
109 | * for 8 byte alignment, we specialcase allocation of the first of 16 |
110 | * 128-byte-long chunks. |
111 | * |
112 | * Note that with the above assumption we automatically have enough |
113 | * place for MAGIC at the start of 2K block. Note also that we |
114 | * overlay union overhead over the chunk, thus the start of the chunk |
115 | * is immediately overwritten after freeing. |
116 | */ |
117 | # define MAX_PACKED 6 |
118 | # define MAX_2_POT_ALGO ((1<<(MAX_PACKED + 1)) - M_OVERHEAD) |
119 | # define TWOK_MASK ((1<<11) - 1) |
ff68c719 |
120 | # define TWOK_MASKED(x) ((u_int)(x) & ~TWOK_MASK) |
121 | # define TWOK_SHIFT(x) ((u_int)(x) & TWOK_MASK) |
cf5c4ad8 |
122 | # define OV_INDEXp(block) ((u_char*)(TWOK_MASKED(block))) |
123 | # define OV_INDEX(block) (*OV_INDEXp(block)) |
124 | # define OV_MAGIC(block,bucket) (*(OV_INDEXp(block) + \ |
125 | (TWOK_SHIFT(block)>>(bucket + 3)) + \ |
126 | (bucket > MAX_NONSHIFT ? 1 : 0))) |
127 | # define CHUNK_SHIFT 0 |
128 | |
129 | static u_char n_blks[11 - 3] = {224, 120, 62, 31, 16, 8, 4, 2}; |
130 | static u_short blk_shift[11 - 3] = {256, 128, 64, 32, |
131 | 16*sizeof(union overhead), |
132 | 8*sizeof(union overhead), |
133 | 4*sizeof(union overhead), |
134 | 2*sizeof(union overhead), |
135 | # define MAX_NONSHIFT 2 /* Shift 64 greater than chunk 32. */ |
136 | }; |
137 | |
cf5c4ad8 |
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 | /* |
55497cff |
148 | * Big allocations are often of the size 2^n bytes. To make them a |
149 | * little bit better, make blocks of size 2^n+pagesize for big n. |
150 | */ |
151 | |
152 | #ifdef TWO_POT_OPTIMIZE |
153 | |
5f05dabc |
154 | # ifndef PERL_PAGESIZE |
155 | # define PERL_PAGESIZE 4096 |
156 | # endif |
157 | # ifndef FIRST_BIG_TWO_POT |
158 | # define FIRST_BIG_TWO_POT 14 /* 16K */ |
159 | # endif |
55497cff |
160 | # define FIRST_BIG_BLOCK (1<<FIRST_BIG_TWO_POT) /* 16K */ |
161 | /* If this value or more, check against bigger blocks. */ |
162 | # define FIRST_BIG_BOUND (FIRST_BIG_BLOCK - M_OVERHEAD) |
163 | /* If less than this value, goes into 2^n-overhead-block. */ |
164 | # define LAST_SMALL_BOUND ((FIRST_BIG_BLOCK>>1) - M_OVERHEAD) |
165 | |
166 | #endif /* TWO_POT_OPTIMIZE */ |
167 | |
72e5b9db |
168 | #if defined(PERL_EMERGENCY_SBRK) && defined(PERL_CORE) |
55497cff |
169 | |
170 | #ifndef BIG_SIZE |
171 | # define BIG_SIZE (1<<16) /* 64K */ |
172 | #endif |
173 | |
174 | static char *emergency_buffer; |
175 | static MEM_SIZE emergency_buffer_size; |
176 | |
177 | static char * |
178 | emergency_sbrk(size) |
179 | MEM_SIZE size; |
180 | { |
181 | if (size >= BIG_SIZE) { |
182 | /* Give the possibility to recover: */ |
183 | die("Out of memory during request for %i bytes", size); |
184 | /* croak may eat too much memory. */ |
185 | } |
186 | |
187 | if (!emergency_buffer) { |
188 | /* First offense, give a possibility to recover by dieing. */ |
189 | /* No malloc involved here: */ |
190 | GV **gvp = (GV**)hv_fetch(defstash, "^M", 2, 0); |
191 | SV *sv; |
192 | char *pv; |
193 | |
194 | if (!gvp) gvp = (GV**)hv_fetch(defstash, "\015", 1, 0); |
195 | if (!gvp || !(sv = GvSV(*gvp)) || !SvPOK(sv) |
196 | || (SvLEN(sv) < (1<<11) - M_OVERHEAD)) |
197 | return (char *)-1; /* Now die die die... */ |
198 | |
199 | /* Got it, now detach SvPV: */ |
bbce6d69 |
200 | pv = SvPV(sv, na); |
55497cff |
201 | /* Check alignment: */ |
ff68c719 |
202 | if (((u_int)(pv - M_OVERHEAD)) & ((1<<11) - 1)) { |
55497cff |
203 | PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n"); |
bbce6d69 |
204 | return (char *)-1; /* die die die */ |
55497cff |
205 | } |
206 | |
207 | emergency_buffer = pv - M_OVERHEAD; |
208 | emergency_buffer_size = SvLEN(sv) + M_OVERHEAD; |
209 | SvPOK_off(sv); |
210 | SvREADONLY_on(sv); |
211 | die("Out of memory!"); /* croak may eat too much memory. */ |
ff68c719 |
212 | } |
213 | else if (emergency_buffer_size >= size) { |
55497cff |
214 | emergency_buffer_size -= size; |
215 | return emergency_buffer + emergency_buffer_size; |
216 | } |
217 | |
218 | return (char *)-1; /* poor guy... */ |
219 | } |
220 | |
72e5b9db |
221 | #else /* !(defined(TWO_POT_OPTIMIZE) && defined(PERL_CORE)) */ |
55497cff |
222 | # define emergency_sbrk(size) -1 |
72e5b9db |
223 | #endif /* !(defined(TWO_POT_OPTIMIZE) && defined(PERL_CORE)) */ |
55497cff |
224 | |
225 | /* |
8d063cd8 |
226 | * nextf[i] is the pointer to the next free block of size 2^(i+3). The |
227 | * smallest allocatable block is 8 bytes. The overhead information |
228 | * precedes the data area returned to the user. |
229 | */ |
230 | #define NBUCKETS 30 |
231 | static union overhead *nextf[NBUCKETS]; |
cf5c4ad8 |
232 | |
233 | #ifdef USE_PERL_SBRK |
234 | #define sbrk(a) Perl_sbrk(a) |
235 | char * Perl_sbrk _((int size)); |
236 | #else |
8d063cd8 |
237 | extern char *sbrk(); |
cf5c4ad8 |
238 | #endif |
8d063cd8 |
239 | |
c07a80fd |
240 | #ifdef DEBUGGING_MSTATS |
8d063cd8 |
241 | /* |
242 | * nmalloc[i] is the difference between the number of mallocs and frees |
243 | * for a given block size. |
244 | */ |
245 | static u_int nmalloc[NBUCKETS]; |
5f05dabc |
246 | static u_int goodsbrk; |
247 | static u_int sbrk_slack; |
248 | static u_int start_slack; |
8d063cd8 |
249 | #endif |
250 | |
760ac839 |
251 | #ifdef DEBUGGING |
4dfc412b |
252 | #define ASSERT(p) if (!(p)) botch(STRINGIFY(p)); else |
ee0007ab |
253 | static void |
8d063cd8 |
254 | botch(s) |
255 | char *s; |
256 | { |
4dfc412b |
257 | PerlIO_printf(PerlIO_stderr(), "assertion botched: %s\n", s); |
8d063cd8 |
258 | abort(); |
259 | } |
260 | #else |
261 | #define ASSERT(p) |
262 | #endif |
263 | |
2304df62 |
264 | Malloc_t |
8d063cd8 |
265 | malloc(nbytes) |
ee0007ab |
266 | register MEM_SIZE nbytes; |
8d063cd8 |
267 | { |
268 | register union overhead *p; |
269 | register int bucket = 0; |
ee0007ab |
270 | register MEM_SIZE shiftr; |
8d063cd8 |
271 | |
c2a5c2d2 |
272 | #if defined(DEBUGGING) || defined(RCHECK) |
ee0007ab |
273 | MEM_SIZE size = nbytes; |
45d8adaa |
274 | #endif |
275 | |
043bf814 |
276 | #ifdef PERL_CORE |
55497cff |
277 | #ifdef HAS_64K_LIMIT |
45d8adaa |
278 | if (nbytes > 0xffff) { |
043bf814 |
279 | PerlIO_printf(PerlIO_stderr(), |
280 | "Allocation too large: %lx\n", (long)nbytes); |
79072805 |
281 | my_exit(1); |
45d8adaa |
282 | } |
55497cff |
283 | #endif /* HAS_64K_LIMIT */ |
45d8adaa |
284 | #ifdef DEBUGGING |
285 | if ((long)nbytes < 0) |
043bf814 |
286 | croak("panic: malloc"); |
45d8adaa |
287 | #endif |
55497cff |
288 | #endif /* PERL_CORE */ |
45d8adaa |
289 | |
8d063cd8 |
290 | /* |
291 | * Convert amount of memory requested into |
292 | * closest block size stored in hash buckets |
293 | * which satisfies request. Account for |
294 | * space used per block for accounting. |
295 | */ |
cf5c4ad8 |
296 | #ifdef PACK_MALLOC |
043bf814 |
297 | if (nbytes == 0) |
298 | nbytes = 1; |
299 | else if (nbytes > MAX_2_POT_ALGO) |
cf5c4ad8 |
300 | #endif |
043bf814 |
301 | { |
55497cff |
302 | #ifdef TWO_POT_OPTIMIZE |
043bf814 |
303 | if (nbytes >= FIRST_BIG_BOUND) |
304 | nbytes -= PERL_PAGESIZE; |
55497cff |
305 | #endif |
043bf814 |
306 | nbytes += M_OVERHEAD; |
307 | nbytes = (nbytes + 3) &~ 3; |
cf5c4ad8 |
308 | } |
8d063cd8 |
309 | shiftr = (nbytes - 1) >> 2; |
310 | /* apart from this loop, this is O(1) */ |
311 | while (shiftr >>= 1) |
312 | bucket++; |
313 | /* |
314 | * If nothing in hash bucket right now, |
315 | * request more memory from the system. |
316 | */ |
317 | if (nextf[bucket] == NULL) |
318 | morecore(bucket); |
45d8adaa |
319 | if ((p = (union overhead *)nextf[bucket]) == NULL) { |
55497cff |
320 | #ifdef PERL_CORE |
ee0007ab |
321 | if (!nomemok) { |
760ac839 |
322 | PerlIO_puts(PerlIO_stderr(),"Out of memory!\n"); |
79072805 |
323 | my_exit(1); |
ee0007ab |
324 | } |
45d8adaa |
325 | #else |
8d063cd8 |
326 | return (NULL); |
45d8adaa |
327 | #endif |
328 | } |
329 | |
55497cff |
330 | #ifdef PERL_CORE |
760ac839 |
331 | DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%lx: (%05d) malloc %ld bytes\n", |
a0d0e21e |
332 | (unsigned long)(p+1),an++,(long)size)); |
55497cff |
333 | #endif /* PERL_CORE */ |
45d8adaa |
334 | |
8d063cd8 |
335 | /* remove from linked list */ |
bf38876a |
336 | #ifdef RCHECK |
337 | if (*((int*)p) & (sizeof(union overhead) - 1)) |
760ac839 |
338 | PerlIO_printf(PerlIO_stderr(), "Corrupt malloc ptr 0x%lx at 0x%lx\n", |
a0d0e21e |
339 | (unsigned long)*((int*)p),(unsigned long)p); |
bf38876a |
340 | #endif |
341 | nextf[bucket] = p->ov_next; |
cf5c4ad8 |
342 | OV_MAGIC(p, bucket) = MAGIC; |
343 | #ifndef PACK_MALLOC |
344 | OV_INDEX(p) = bucket; |
345 | #endif |
8d063cd8 |
346 | #ifdef RCHECK |
347 | /* |
348 | * Record allocated size of block and |
349 | * bound space with magic numbers. |
350 | */ |
c2a5c2d2 |
351 | nbytes = (size + M_OVERHEAD + 3) &~ 3; |
8d063cd8 |
352 | if (nbytes <= 0x10000) |
353 | p->ov_size = nbytes - 1; |
354 | p->ov_rmagic = RMAGIC; |
355 | *((u_int *)((caddr_t)p + nbytes - RSLOP)) = RMAGIC; |
356 | #endif |
cf5c4ad8 |
357 | return ((Malloc_t)(p + CHUNK_SHIFT)); |
8d063cd8 |
358 | } |
359 | |
360 | /* |
361 | * Allocate more memory to the indicated bucket. |
362 | */ |
a0d0e21e |
363 | static void |
8d063cd8 |
364 | morecore(bucket) |
a687059c |
365 | register int bucket; |
8d063cd8 |
366 | { |
367 | register union overhead *op; |
368 | register int rnu; /* 2^rnu bytes will be requested */ |
369 | register int nblks; /* become nblks blocks of the desired size */ |
bbce6d69 |
370 | register MEM_SIZE siz, needed; |
cf5c4ad8 |
371 | int slack = 0; |
8d063cd8 |
372 | |
373 | if (nextf[bucket]) |
374 | return; |
55497cff |
375 | if (bucket == (sizeof(MEM_SIZE)*8 - 3)) { |
376 | croak("Allocation too large"); |
377 | } |
8d063cd8 |
378 | /* |
379 | * Insure memory is allocated |
380 | * on a page boundary. Should |
381 | * make getpageize call? |
382 | */ |
ee0007ab |
383 | #ifndef atarist /* on the atari we dont have to worry about this */ |
8d063cd8 |
384 | op = (union overhead *)sbrk(0); |
cf5c4ad8 |
385 | # ifndef I286 |
c030ccd9 |
386 | if ((UV)op & (0x7FF >> CHUNK_SHIFT)) { |
387 | slack = (0x800 >> CHUNK_SHIFT) - ((UV)op & (0x7FF >> CHUNK_SHIFT)); |
388 | (void)sbrk(slack); |
5f05dabc |
389 | # if defined(DEBUGGING_MSTATS) |
c030ccd9 |
390 | sbrk_slack += slack; |
cf5c4ad8 |
391 | # endif |
c030ccd9 |
392 | } |
cf5c4ad8 |
393 | # else |
a687059c |
394 | /* The sbrk(0) call on the I286 always returns the next segment */ |
cf5c4ad8 |
395 | # endif |
ee0007ab |
396 | #endif /* atarist */ |
a687059c |
397 | |
ee0007ab |
398 | #if !(defined(I286) || defined(atarist)) |
8d063cd8 |
399 | /* take 2k unless the block is bigger than that */ |
400 | rnu = (bucket <= 8) ? 11 : bucket + 3; |
a687059c |
401 | #else |
402 | /* take 16k unless the block is bigger than that |
ee0007ab |
403 | (80286s like large segments!), probably good on the atari too */ |
a687059c |
404 | rnu = (bucket <= 11) ? 14 : bucket + 3; |
405 | #endif |
8d063cd8 |
406 | nblks = 1 << (rnu - (bucket + 3)); /* how many blocks to get */ |
bbce6d69 |
407 | needed = (MEM_SIZE)1 << rnu; |
55497cff |
408 | #ifdef TWO_POT_OPTIMIZE |
bbce6d69 |
409 | needed += (bucket >= (FIRST_BIG_TWO_POT - 3) ? PERL_PAGESIZE : 0); |
55497cff |
410 | #endif |
bbce6d69 |
411 | op = (union overhead *)sbrk(needed); |
8d063cd8 |
412 | /* no more room! */ |
ff68c719 |
413 | if (op == (union overhead *)-1) { |
414 | op = (union overhead *)emergency_sbrk(needed); |
415 | if (op == (union overhead *)-1) |
8d063cd8 |
416 | return; |
ff68c719 |
417 | } |
5f05dabc |
418 | #ifdef DEBUGGING_MSTATS |
419 | goodsbrk += needed; |
420 | #endif |
8d063cd8 |
421 | /* |
422 | * Round up to minimum allocation size boundary |
423 | * and deduct from block count to reflect. |
424 | */ |
a687059c |
425 | #ifndef I286 |
cf5c4ad8 |
426 | # ifdef PACK_MALLOC |
c030ccd9 |
427 | if ((UV)op & 0x7FF) |
cf5c4ad8 |
428 | croak("panic: Off-page sbrk"); |
429 | # endif |
c030ccd9 |
430 | if ((UV)op & 7) { |
431 | op = (union overhead *)(((UV)op + 8) & ~7); |
8d063cd8 |
432 | nblks--; |
433 | } |
a687059c |
434 | #else |
435 | /* Again, this should always be ok on an 80286 */ |
436 | #endif |
8d063cd8 |
437 | /* |
438 | * Add new memory allocated to that on |
439 | * free list for this hash bucket. |
440 | */ |
8d063cd8 |
441 | siz = 1 << (bucket + 3); |
cf5c4ad8 |
442 | #ifdef PACK_MALLOC |
443 | *(u_char*)op = bucket; /* Fill index. */ |
444 | if (bucket <= MAX_PACKED - 3) { |
445 | op = (union overhead *) ((char*)op + blk_shift[bucket]); |
446 | nblks = n_blks[bucket]; |
447 | # ifdef DEBUGGING_MSTATS |
448 | start_slack += blk_shift[bucket]; |
449 | # endif |
450 | } else if (bucket <= 11 - 1 - 3) { |
451 | op = (union overhead *) ((char*)op + blk_shift[bucket]); |
452 | /* nblks = n_blks[bucket]; */ |
453 | siz -= sizeof(union overhead); |
454 | } else op++; /* One chunk per block. */ |
455 | #endif /* !PACK_MALLOC */ |
456 | nextf[bucket] = op; |
5f05dabc |
457 | #ifdef DEBUGGING_MSTATS |
458 | nmalloc[bucket] += nblks; |
459 | #endif |
8d063cd8 |
460 | while (--nblks > 0) { |
461 | op->ov_next = (union overhead *)((caddr_t)op + siz); |
462 | op = (union overhead *)((caddr_t)op + siz); |
463 | } |
8595d6f1 |
464 | /* Not all sbrks return zeroed memory.*/ |
cf5c4ad8 |
465 | op->ov_next = (union overhead *)NULL; |
cf5c4ad8 |
466 | #ifdef PACK_MALLOC |
467 | if (bucket == 7 - 3) { /* Special case, explanation is above. */ |
468 | union overhead *n_op = nextf[7 - 3]->ov_next; |
469 | nextf[7 - 3] = (union overhead *)((caddr_t)nextf[7 - 3] |
470 | - sizeof(union overhead)); |
471 | nextf[7 - 3]->ov_next = n_op; |
472 | } |
473 | #endif /* !PACK_MALLOC */ |
8d063cd8 |
474 | } |
475 | |
94b6baf5 |
476 | Free_t |
352d5a3a |
477 | free(mp) |
2304df62 |
478 | Malloc_t mp; |
8d063cd8 |
479 | { |
ee0007ab |
480 | register MEM_SIZE size; |
8d063cd8 |
481 | register union overhead *op; |
352d5a3a |
482 | char *cp = (char*)mp; |
cf5c4ad8 |
483 | #ifdef PACK_MALLOC |
484 | u_char bucket; |
485 | #endif |
8d063cd8 |
486 | |
55497cff |
487 | #ifdef PERL_CORE |
760ac839 |
488 | DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%lx: (%05d) free\n",(unsigned long)cp,an++)); |
55497cff |
489 | #endif /* PERL_CORE */ |
45d8adaa |
490 | |
cf5c4ad8 |
491 | if (cp == NULL) |
492 | return; |
493 | op = (union overhead *)((caddr_t)cp |
494 | - sizeof (union overhead) * CHUNK_SHIFT); |
495 | #ifdef PACK_MALLOC |
496 | bucket = OV_INDEX(op); |
497 | #endif |
cf5c4ad8 |
498 | if (OV_MAGIC(op, bucket) != MAGIC) { |
499 | static bad_free_warn = -1; |
500 | if (bad_free_warn == -1) { |
501 | char *pbf = getenv("PERL_BADFREE"); |
502 | bad_free_warn = (pbf) ? atoi(pbf) : 1; |
503 | } |
504 | if (!bad_free_warn) |
505 | return; |
8990e307 |
506 | #ifdef RCHECK |
a687059c |
507 | warn("%s free() ignored", |
8990e307 |
508 | op->ov_rmagic == RMAGIC - 1 ? "Duplicate" : "Bad"); |
509 | #else |
510 | warn("Bad free() ignored"); |
511 | #endif |
8d063cd8 |
512 | return; /* sanity */ |
378cc40b |
513 | } |
8d063cd8 |
514 | #ifdef RCHECK |
515 | ASSERT(op->ov_rmagic == RMAGIC); |
c2a5c2d2 |
516 | if (OV_INDEX(op) <= MAX_SHORT_BUCKET) |
8d063cd8 |
517 | ASSERT(*(u_int *)((caddr_t)op + op->ov_size + 1 - RSLOP) == RMAGIC); |
8990e307 |
518 | op->ov_rmagic = RMAGIC - 1; |
8d063cd8 |
519 | #endif |
cf5c4ad8 |
520 | ASSERT(OV_INDEX(op) < NBUCKETS); |
521 | size = OV_INDEX(op); |
8d063cd8 |
522 | op->ov_next = nextf[size]; |
523 | nextf[size] = op; |
8d063cd8 |
524 | } |
525 | |
526 | /* |
527 | * When a program attempts "storage compaction" as mentioned in the |
528 | * old malloc man page, it realloc's an already freed block. Usually |
529 | * this is the last block it freed; occasionally it might be farther |
530 | * back. We have to search all the free lists for the block in order |
531 | * to determine its bucket: 1st we make one pass thru the lists |
532 | * checking only the first block in each; if that fails we search |
378cc40b |
533 | * ``reall_srchlen'' blocks in each list for a match (the variable |
8d063cd8 |
534 | * is extern so the caller can modify it). If that fails we just copy |
535 | * however many bytes was given to realloc() and hope it's not huge. |
536 | */ |
378cc40b |
537 | int reall_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */ |
8d063cd8 |
538 | |
2304df62 |
539 | Malloc_t |
352d5a3a |
540 | realloc(mp, nbytes) |
2304df62 |
541 | Malloc_t mp; |
ee0007ab |
542 | MEM_SIZE nbytes; |
8d063cd8 |
543 | { |
ee0007ab |
544 | register MEM_SIZE onb; |
8d063cd8 |
545 | union overhead *op; |
546 | char *res; |
547 | register int i; |
548 | int was_alloced = 0; |
352d5a3a |
549 | char *cp = (char*)mp; |
8d063cd8 |
550 | |
45d8adaa |
551 | #ifdef DEBUGGING |
ee0007ab |
552 | MEM_SIZE size = nbytes; |
45d8adaa |
553 | #endif |
554 | |
043bf814 |
555 | #ifdef PERL_CORE |
55497cff |
556 | #ifdef HAS_64K_LIMIT |
45d8adaa |
557 | if (nbytes > 0xffff) { |
043bf814 |
558 | PerlIO_printf(PerlIO_stderr(), |
559 | "Reallocation too large: %lx\n", size); |
79072805 |
560 | my_exit(1); |
45d8adaa |
561 | } |
55497cff |
562 | #endif /* HAS_64K_LIMIT */ |
45d8adaa |
563 | if (!cp) |
ee0007ab |
564 | return malloc(nbytes); |
45d8adaa |
565 | #ifdef DEBUGGING |
566 | if ((long)nbytes < 0) |
463ee0b2 |
567 | croak("panic: realloc"); |
45d8adaa |
568 | #endif |
55497cff |
569 | #endif /* PERL_CORE */ |
45d8adaa |
570 | |
cf5c4ad8 |
571 | op = (union overhead *)((caddr_t)cp |
572 | - sizeof (union overhead) * CHUNK_SHIFT); |
573 | i = OV_INDEX(op); |
574 | if (OV_MAGIC(op, i) == MAGIC) { |
55497cff |
575 | was_alloced = 1; |
8d063cd8 |
576 | } else { |
577 | /* |
578 | * Already free, doing "compaction". |
579 | * |
580 | * Search for the old block of memory on the |
581 | * free list. First, check the most common |
582 | * case (last element free'd), then (this failing) |
378cc40b |
583 | * the last ``reall_srchlen'' items free'd. |
8d063cd8 |
584 | * If all lookups fail, then assume the size of |
585 | * the memory block being realloc'd is the |
586 | * smallest possible. |
587 | */ |
588 | if ((i = findbucket(op, 1)) < 0 && |
378cc40b |
589 | (i = findbucket(op, reall_srchlen)) < 0) |
8d063cd8 |
590 | i = 0; |
591 | } |
cf5c4ad8 |
592 | onb = (1L << (i + 3)) - |
593 | #ifdef PACK_MALLOC |
594 | (i <= (MAX_PACKED - 3) ? 0 : M_OVERHEAD) |
595 | #else |
596 | M_OVERHEAD |
597 | #endif |
55497cff |
598 | #ifdef TWO_POT_OPTIMIZE |
599 | + (i >= (FIRST_BIG_TWO_POT - 3) ? PERL_PAGESIZE : 0) |
600 | #endif |
cf5c4ad8 |
601 | ; |
55497cff |
602 | /* |
603 | * avoid the copy if same size block. |
604 | * We are not agressive with boundary cases. Note that it is |
605 | * possible for small number of cases give false negative if |
606 | * both new size and old one are in the bucket for |
607 | * FIRST_BIG_TWO_POT, but the new one is near the lower end. |
608 | */ |
8d063cd8 |
609 | if (was_alloced && |
55497cff |
610 | nbytes <= onb && (nbytes > ( (onb >> 1) - M_OVERHEAD ) |
611 | #ifdef TWO_POT_OPTIMIZE |
612 | || (i == (FIRST_BIG_TWO_POT - 3) |
613 | && nbytes >= LAST_SMALL_BOUND ) |
614 | #endif |
615 | )) { |
a687059c |
616 | #ifdef RCHECK |
617 | /* |
618 | * Record new allocated size of block and |
619 | * bound space with magic numbers. |
620 | */ |
c2a5c2d2 |
621 | if (OV_INDEX(op) <= MAX_SHORT_BUCKET) { |
a687059c |
622 | /* |
623 | * Convert amount of memory requested into |
624 | * closest block size stored in hash buckets |
625 | * which satisfies request. Account for |
626 | * space used per block for accounting. |
627 | */ |
cf5c4ad8 |
628 | nbytes += M_OVERHEAD; |
a687059c |
629 | nbytes = (nbytes + 3) &~ 3; |
630 | op->ov_size = nbytes - 1; |
631 | *((u_int *)((caddr_t)op + nbytes - RSLOP)) = RMAGIC; |
632 | } |
633 | #endif |
45d8adaa |
634 | res = cp; |
a687059c |
635 | } |
45d8adaa |
636 | else { |
637 | if ((res = (char*)malloc(nbytes)) == NULL) |
638 | return (NULL); |
639 | if (cp != res) /* common optimization */ |
ee0007ab |
640 | Copy(cp, res, (MEM_SIZE)(nbytes<onb?nbytes:onb), char); |
45d8adaa |
641 | if (was_alloced) |
642 | free(cp); |
643 | } |
644 | |
55497cff |
645 | #ifdef PERL_CORE |
45d8adaa |
646 | #ifdef DEBUGGING |
a0d0e21e |
647 | if (debug & 128) { |
760ac839 |
648 | PerlIO_printf(PerlIO_stderr(), "0x%lx: (%05d) rfree\n",(unsigned long)res,an++); |
649 | PerlIO_printf(PerlIO_stderr(), "0x%lx: (%05d) realloc %ld bytes\n", |
a0d0e21e |
650 | (unsigned long)res,an++,(long)size); |
651 | } |
45d8adaa |
652 | #endif |
55497cff |
653 | #endif /* PERL_CORE */ |
2304df62 |
654 | return ((Malloc_t)res); |
8d063cd8 |
655 | } |
656 | |
657 | /* |
658 | * Search ``srchlen'' elements of each free list for a block whose |
659 | * header starts at ``freep''. If srchlen is -1 search the whole list. |
660 | * Return bucket number, or -1 if not found. |
661 | */ |
ee0007ab |
662 | static int |
8d063cd8 |
663 | findbucket(freep, srchlen) |
664 | union overhead *freep; |
665 | int srchlen; |
666 | { |
667 | register union overhead *p; |
668 | register int i, j; |
669 | |
670 | for (i = 0; i < NBUCKETS; i++) { |
671 | j = 0; |
672 | for (p = nextf[i]; p && j != srchlen; p = p->ov_next) { |
673 | if (p == freep) |
674 | return (i); |
675 | j++; |
676 | } |
677 | } |
678 | return (-1); |
679 | } |
680 | |
cf5c4ad8 |
681 | Malloc_t |
682 | calloc(elements, size) |
683 | register MEM_SIZE elements; |
684 | register MEM_SIZE size; |
685 | { |
686 | long sz = elements * size; |
687 | Malloc_t p = malloc(sz); |
688 | |
689 | if (p) { |
690 | memset((void*)p, 0, sz); |
691 | } |
692 | return p; |
693 | } |
694 | |
c07a80fd |
695 | #ifdef DEBUGGING_MSTATS |
8d063cd8 |
696 | /* |
697 | * mstats - print out statistics about malloc |
698 | * |
699 | * Prints two lines of numbers, one showing the length of the free list |
700 | * for each size category, the second showing the number of mallocs - |
701 | * frees for each size category. |
702 | */ |
ee0007ab |
703 | void |
c07a80fd |
704 | dump_mstats(s) |
8d063cd8 |
705 | char *s; |
706 | { |
707 | register int i, j; |
708 | register union overhead *p; |
5f05dabc |
709 | int topbucket=0, totfree=0, total=0; |
c07a80fd |
710 | u_int nfree[NBUCKETS]; |
8d063cd8 |
711 | |
c07a80fd |
712 | for (i=0; i < NBUCKETS; i++) { |
8d063cd8 |
713 | for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) |
714 | ; |
c07a80fd |
715 | nfree[i] = j; |
716 | totfree += nfree[i] * (1 << (i + 3)); |
5f05dabc |
717 | total += nmalloc[i] * (1 << (i + 3)); |
718 | if (nmalloc[i]) |
c07a80fd |
719 | topbucket = i; |
720 | } |
721 | if (s) |
760ac839 |
722 | PerlIO_printf(PerlIO_stderr(), "Memory allocation statistics %s (buckets 8..%d)\n", |
c07a80fd |
723 | s, (1 << (topbucket + 3)) ); |
5f05dabc |
724 | PerlIO_printf(PerlIO_stderr(), "%8d free:", totfree); |
c07a80fd |
725 | for (i=0; i <= topbucket; i++) { |
5f05dabc |
726 | PerlIO_printf(PerlIO_stderr(), (i<5 || i==7)?" %5d": (i<9)?" %3d":" %d", nfree[i]); |
8d063cd8 |
727 | } |
5f05dabc |
728 | PerlIO_printf(PerlIO_stderr(), "\n%8d used:", total - totfree); |
c07a80fd |
729 | for (i=0; i <= topbucket; i++) { |
5f05dabc |
730 | PerlIO_printf(PerlIO_stderr(), (i<5 || i==7)?" %5d": (i<9)?" %3d":" %d", nmalloc[i] - nfree[i]); |
c07a80fd |
731 | } |
5f05dabc |
732 | PerlIO_printf(PerlIO_stderr(), "\nTotal sbrk(): %8d. Odd ends: sbrk(): %7d, malloc(): %7d bytes.\n", |
733 | goodsbrk + sbrk_slack, sbrk_slack, start_slack); |
c07a80fd |
734 | } |
735 | #else |
736 | void |
737 | dump_mstats(s) |
738 | char *s; |
739 | { |
8d063cd8 |
740 | } |
741 | #endif |
a687059c |
742 | #endif /* lint */ |
cf5c4ad8 |
743 | |
744 | |
745 | #ifdef USE_PERL_SBRK |
746 | |
760ac839 |
747 | # ifdef NeXT |
748 | # define PERL_SBRK_VIA_MALLOC |
749 | # endif |
750 | |
751 | # ifdef PERL_SBRK_VIA_MALLOC |
72e5b9db |
752 | # if defined(HIDEMYMALLOC) || defined(EMBEDMYMALLOC) |
760ac839 |
753 | # undef malloc |
754 | # else |
72e5b9db |
755 | # include "Error: -DPERL_SBRK_VIA_MALLOC needs -D(HIDE|EMBED)MYMALLOC" |
760ac839 |
756 | # endif |
cf5c4ad8 |
757 | |
758 | /* it may seem schizophrenic to use perl's malloc and let it call system */ |
759 | /* malloc, the reason for that is only the 3.2 version of the OS that had */ |
760 | /* frequent core dumps within nxzonefreenolock. This sbrk routine put an */ |
761 | /* end to the cores */ |
762 | |
760ac839 |
763 | # define SYSTEM_ALLOC(a) malloc(a) |
cf5c4ad8 |
764 | |
760ac839 |
765 | # endif /* PERL_SBRK_VIA_MALLOC */ |
cf5c4ad8 |
766 | |
767 | static IV Perl_sbrk_oldchunk; |
768 | static long Perl_sbrk_oldsize; |
769 | |
760ac839 |
770 | # define PERLSBRK_32_K (1<<15) |
771 | # define PERLSBRK_64_K (1<<16) |
cf5c4ad8 |
772 | |
773 | char * |
774 | Perl_sbrk(size) |
775 | int size; |
776 | { |
777 | IV got; |
778 | int small, reqsize; |
779 | |
780 | if (!size) return 0; |
55497cff |
781 | #ifdef PERL_CORE |
cf5c4ad8 |
782 | reqsize = size; /* just for the DEBUG_m statement */ |
783 | #endif |
784 | if (size <= Perl_sbrk_oldsize) { |
785 | got = Perl_sbrk_oldchunk; |
786 | Perl_sbrk_oldchunk += size; |
787 | Perl_sbrk_oldsize -= size; |
788 | } else { |
789 | if (size >= PERLSBRK_32_K) { |
790 | small = 0; |
791 | } else { |
55497cff |
792 | #ifndef PERL_CORE |
cf5c4ad8 |
793 | reqsize = size; |
794 | #endif |
795 | size = PERLSBRK_64_K; |
796 | small = 1; |
797 | } |
798 | got = (IV)SYSTEM_ALLOC(size); |
799 | if (small) { |
800 | /* Chunk is small, register the rest for future allocs. */ |
801 | Perl_sbrk_oldchunk = got + reqsize; |
802 | Perl_sbrk_oldsize = size - reqsize; |
803 | } |
804 | } |
805 | |
55497cff |
806 | #ifdef PERL_CORE |
760ac839 |
807 | DEBUG_m(PerlIO_printf(PerlIO_stderr(), "sbrk malloc size %ld (reqsize %ld), left size %ld, give addr 0x%lx\n", |
cf5c4ad8 |
808 | size, reqsize, Perl_sbrk_oldsize, got)); |
809 | #endif |
810 | |
811 | return (void *)got; |
812 | } |
813 | |
814 | #endif /* ! defined USE_PERL_SBRK */ |