Commit | Line | Data |
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177c0ea7 | 1 | /* Block-relocating memory allocator. |
acaf905b | 2 | Copyright (C) 1993, 1995, 2000-2012 Free Software Foundation, Inc. |
dcfdbac7 JB |
3 | |
4 | This file is part of GNU Emacs. | |
5 | ||
9ec0b715 | 6 | GNU Emacs is free software: you can redistribute it and/or modify |
dcfdbac7 | 7 | it under the terms of the GNU General Public License as published by |
9ec0b715 GM |
8 | the Free Software Foundation, either version 3 of the License, or |
9 | (at your option) any later version. | |
dcfdbac7 JB |
10 | |
11 | GNU Emacs is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
9ec0b715 | 17 | along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ |
dcfdbac7 JB |
18 | |
19 | /* NOTES: | |
20 | ||
eb8c3be9 | 21 | Only relocate the blocs necessary for SIZE in r_alloc_sbrk, |
dcfdbac7 | 22 | rather than all of them. This means allowing for a possible |
abe9ff32 | 23 | hole between the first bloc and the end of malloc storage. */ |
dcfdbac7 | 24 | |
2c46d29f | 25 | #ifdef emacs |
aef4d570 | 26 | |
18160b98 | 27 | #include <config.h> |
0328b6de | 28 | |
956ace37 | 29 | #include "lisp.h" /* Needed for VALBITS. */ |
a4766fd5 | 30 | #include "blockinput.h" |
0a58f946 | 31 | |
642a1733 | 32 | #include <unistd.h> |
a8c0e5ea | 33 | |
b0119c68 | 34 | #ifdef DOUG_LEA_MALLOC |
177c0ea7 | 35 | #define M_TOP_PAD -2 |
971de7fb | 36 | extern int mallopt (int, int); |
0a58f946 | 37 | #else /* not DOUG_LEA_MALLOC */ |
a2c23c92 | 38 | #ifndef SYSTEM_MALLOC |
b1685c5f | 39 | extern size_t __malloc_extra_blocks; |
a2c23c92 | 40 | #endif /* SYSTEM_MALLOC */ |
0a58f946 | 41 | #endif /* not DOUG_LEA_MALLOC */ |
49081834 | 42 | |
d5179acc | 43 | #else /* not emacs */ |
aef4d570 | 44 | |
2c46d29f | 45 | #include <stddef.h> |
aef4d570 | 46 | |
aef4d570 RM |
47 | #include <unistd.h> |
48 | #include <malloc.h> | |
aef4d570 | 49 | |
d5179acc | 50 | #endif /* not emacs */ |
2c46d29f | 51 | |
0a58f946 | 52 | |
d5179acc | 53 | #include "getpagesize.h" |
dcfdbac7 | 54 | |
261cb4bb PE |
55 | typedef size_t SIZE; |
56 | typedef void *POINTER; | |
dcfdbac7 JB |
57 | #define NIL ((POINTER) 0) |
58 | ||
2c46d29f RS |
59 | /* A flag to indicate whether we have initialized ralloc yet. For |
60 | Emacs's sake, please do not make this local to malloc_init; on some | |
61 | machines, the dumping procedure makes all static variables | |
62 | read-only. On these machines, the word static is #defined to be | |
63 | the empty string, meaning that r_alloc_initialized becomes an | |
0a58f946 GM |
64 | automatic variable, and loses its value each time Emacs is started |
65 | up. */ | |
66 | ||
2c46d29f RS |
67 | static int r_alloc_initialized = 0; |
68 | ||
971de7fb | 69 | static void r_alloc_init (void); |
0a58f946 | 70 | |
dcfdbac7 | 71 | \f |
956ace37 JB |
72 | /* Declarations for working with the malloc, ralloc, and system breaks. */ |
73 | ||
abe9ff32 | 74 | /* Function to set the real break value. */ |
361358ea | 75 | POINTER (*real_morecore) (long int); |
dcfdbac7 | 76 | |
abe9ff32 | 77 | /* The break value, as seen by malloc. */ |
dcfdbac7 JB |
78 | static POINTER virtual_break_value; |
79 | ||
abe9ff32 RS |
80 | /* The address of the end of the last data in use by ralloc, |
81 | including relocatable blocs as well as malloc data. */ | |
dcfdbac7 JB |
82 | static POINTER break_value; |
83 | ||
7516b7d5 RS |
84 | /* This is the size of a page. We round memory requests to this boundary. */ |
85 | static int page_size; | |
86 | ||
177c0ea7 | 87 | /* Whenever we get memory from the system, get this many extra bytes. This |
ad3bb3d2 | 88 | must be a multiple of page_size. */ |
7516b7d5 RS |
89 | static int extra_bytes; |
90 | ||
dcfdbac7 | 91 | /* Macros for rounding. Note that rounding to any value is possible |
abe9ff32 | 92 | by changing the definition of PAGE. */ |
dcfdbac7 | 93 | #define PAGE (getpagesize ()) |
f7a009a5 RM |
94 | #define ROUNDUP(size) (((unsigned long int) (size) + page_size - 1) \ |
95 | & ~(page_size - 1)) | |
e429caa2 | 96 | |
5e617bc2 | 97 | #define MEM_ALIGN sizeof (double) |
e429caa2 KH |
98 | #define MEM_ROUNDUP(addr) (((unsigned long int)(addr) + MEM_ALIGN - 1) \ |
99 | & ~(MEM_ALIGN - 1)) | |
0a58f946 | 100 | |
aeac019e GM |
101 | /* The hook `malloc' uses for the function which gets more space |
102 | from the system. */ | |
103 | ||
104 | #ifndef SYSTEM_MALLOC | |
361358ea | 105 | extern POINTER (*__morecore) (long int); |
aeac019e GM |
106 | #endif |
107 | ||
108 | ||
e429caa2 | 109 | \f |
0a58f946 GM |
110 | /*********************************************************************** |
111 | Implementation using sbrk | |
112 | ***********************************************************************/ | |
113 | ||
abe9ff32 RS |
114 | /* Data structures of heaps and blocs. */ |
115 | ||
116 | /* The relocatable objects, or blocs, and the malloc data | |
117 | both reside within one or more heaps. | |
118 | Each heap contains malloc data, running from `start' to `bloc_start', | |
119 | and relocatable objects, running from `bloc_start' to `free'. | |
120 | ||
121 | Relocatable objects may relocate within the same heap | |
122 | or may move into another heap; the heaps themselves may grow | |
123 | but they never move. | |
124 | ||
125 | We try to make just one heap and make it larger as necessary. | |
8e6208c5 | 126 | But sometimes we can't do that, because we can't get contiguous |
abe9ff32 | 127 | space to add onto the heap. When that happens, we start a new heap. */ |
177c0ea7 | 128 | |
e429caa2 KH |
129 | typedef struct heap |
130 | { | |
131 | struct heap *next; | |
132 | struct heap *prev; | |
abe9ff32 | 133 | /* Start of memory range of this heap. */ |
e429caa2 | 134 | POINTER start; |
abe9ff32 | 135 | /* End of memory range of this heap. */ |
e429caa2 | 136 | POINTER end; |
abe9ff32 RS |
137 | /* Start of relocatable data in this heap. */ |
138 | POINTER bloc_start; | |
139 | /* Start of unused space in this heap. */ | |
140 | POINTER free; | |
47f13333 RS |
141 | /* First bloc in this heap. */ |
142 | struct bp *first_bloc; | |
143 | /* Last bloc in this heap. */ | |
144 | struct bp *last_bloc; | |
e429caa2 KH |
145 | } *heap_ptr; |
146 | ||
147 | #define NIL_HEAP ((heap_ptr) 0) | |
e429caa2 | 148 | |
abe9ff32 RS |
149 | /* This is the first heap object. |
150 | If we need additional heap objects, each one resides at the beginning of | |
151 | the space it covers. */ | |
152 | static struct heap heap_base; | |
153 | ||
154 | /* Head and tail of the list of heaps. */ | |
e429caa2 KH |
155 | static heap_ptr first_heap, last_heap; |
156 | ||
157 | /* These structures are allocated in the malloc arena. | |
158 | The linked list is kept in order of increasing '.data' members. | |
159 | The data blocks abut each other; if b->next is non-nil, then | |
177c0ea7 | 160 | b->data + b->size == b->next->data. |
49f82b3d RS |
161 | |
162 | An element with variable==NIL denotes a freed block, which has not yet | |
f96f2c5b JB |
163 | been collected. They may only appear while r_alloc_freeze_level > 0, |
164 | and will be freed when the arena is thawed. Currently, these blocs are | |
165 | not reusable, while the arena is frozen. Very inefficient. */ | |
49f82b3d | 166 | |
e429caa2 KH |
167 | typedef struct bp |
168 | { | |
169 | struct bp *next; | |
170 | struct bp *prev; | |
171 | POINTER *variable; | |
172 | POINTER data; | |
173 | SIZE size; | |
8e6208c5 | 174 | POINTER new_data; /* temporarily used for relocation */ |
49f82b3d | 175 | struct heap *heap; /* Heap this bloc is in. */ |
e429caa2 KH |
176 | } *bloc_ptr; |
177 | ||
178 | #define NIL_BLOC ((bloc_ptr) 0) | |
179 | #define BLOC_PTR_SIZE (sizeof (struct bp)) | |
180 | ||
abe9ff32 | 181 | /* Head and tail of the list of relocatable blocs. */ |
e429caa2 KH |
182 | static bloc_ptr first_bloc, last_bloc; |
183 | ||
49f82b3d RS |
184 | static int use_relocatable_buffers; |
185 | ||
186 | /* If >0, no relocation whatsoever takes place. */ | |
187 | static int r_alloc_freeze_level; | |
188 | ||
dcfdbac7 | 189 | \f |
956ace37 JB |
190 | /* Functions to get and return memory from the system. */ |
191 | ||
abe9ff32 RS |
192 | /* Find the heap that ADDRESS falls within. */ |
193 | ||
194 | static heap_ptr | |
971de7fb | 195 | find_heap (POINTER address) |
abe9ff32 RS |
196 | { |
197 | heap_ptr heap; | |
198 | ||
199 | for (heap = last_heap; heap; heap = heap->prev) | |
200 | { | |
201 | if (heap->start <= address && address <= heap->end) | |
202 | return heap; | |
203 | } | |
204 | ||
205 | return NIL_HEAP; | |
206 | } | |
207 | ||
208 | /* Find SIZE bytes of space in a heap. | |
209 | Try to get them at ADDRESS (which must fall within some heap's range) | |
210 | if we can get that many within one heap. | |
211 | ||
e429caa2 | 212 | If enough space is not presently available in our reserve, this means |
8e6208c5 KH |
213 | getting more page-aligned space from the system. If the returned space |
214 | is not contiguous to the last heap, allocate a new heap, and append it | |
0d26e0b6 | 215 | to the heap list. |
abe9ff32 | 216 | |
0d26e0b6 JB |
217 | obtain does not try to keep track of whether space is in use or not |
218 | in use. It just returns the address of SIZE bytes that fall within a | |
219 | single heap. If you call obtain twice in a row with the same arguments, | |
220 | you typically get the same value. It's the caller's responsibility to | |
221 | keep track of what space is in use. | |
dcfdbac7 | 222 | |
e429caa2 KH |
223 | Return the address of the space if all went well, or zero if we couldn't |
224 | allocate the memory. */ | |
abe9ff32 | 225 | |
e429caa2 | 226 | static POINTER |
971de7fb | 227 | obtain (POINTER address, SIZE size) |
dcfdbac7 | 228 | { |
e429caa2 KH |
229 | heap_ptr heap; |
230 | SIZE already_available; | |
dcfdbac7 | 231 | |
abe9ff32 | 232 | /* Find the heap that ADDRESS falls within. */ |
e429caa2 | 233 | for (heap = last_heap; heap; heap = heap->prev) |
dcfdbac7 | 234 | { |
e429caa2 KH |
235 | if (heap->start <= address && address <= heap->end) |
236 | break; | |
237 | } | |
dcfdbac7 | 238 | |
e429caa2 | 239 | if (! heap) |
1088b922 | 240 | emacs_abort (); |
dcfdbac7 | 241 | |
abe9ff32 RS |
242 | /* If we can't fit SIZE bytes in that heap, |
243 | try successive later heaps. */ | |
91a211b5 | 244 | while (heap && (char *) address + size > (char *) heap->end) |
e429caa2 KH |
245 | { |
246 | heap = heap->next; | |
247 | if (heap == NIL_HEAP) | |
248 | break; | |
249 | address = heap->bloc_start; | |
dcfdbac7 JB |
250 | } |
251 | ||
abe9ff32 RS |
252 | /* If we can't fit them within any existing heap, |
253 | get more space. */ | |
e429caa2 KH |
254 | if (heap == NIL_HEAP) |
255 | { | |
256 | POINTER new = (*real_morecore)(0); | |
257 | SIZE get; | |
98b7fe02 | 258 | |
e429caa2 | 259 | already_available = (char *)last_heap->end - (char *)address; |
dcfdbac7 | 260 | |
e429caa2 KH |
261 | if (new != last_heap->end) |
262 | { | |
abe9ff32 RS |
263 | /* Someone else called sbrk. Make a new heap. */ |
264 | ||
265 | heap_ptr new_heap = (heap_ptr) MEM_ROUNDUP (new); | |
266 | POINTER bloc_start = (POINTER) MEM_ROUNDUP ((POINTER)(new_heap + 1)); | |
e429caa2 | 267 | |
91a211b5 | 268 | if ((*real_morecore) ((char *) bloc_start - (char *) new) != new) |
e429caa2 KH |
269 | return 0; |
270 | ||
271 | new_heap->start = new; | |
272 | new_heap->end = bloc_start; | |
273 | new_heap->bloc_start = bloc_start; | |
abe9ff32 | 274 | new_heap->free = bloc_start; |
e429caa2 KH |
275 | new_heap->next = NIL_HEAP; |
276 | new_heap->prev = last_heap; | |
47f13333 RS |
277 | new_heap->first_bloc = NIL_BLOC; |
278 | new_heap->last_bloc = NIL_BLOC; | |
e429caa2 KH |
279 | last_heap->next = new_heap; |
280 | last_heap = new_heap; | |
281 | ||
282 | address = bloc_start; | |
283 | already_available = 0; | |
284 | } | |
dcfdbac7 | 285 | |
abe9ff32 RS |
286 | /* Add space to the last heap (which we may have just created). |
287 | Get some extra, so we can come here less often. */ | |
288 | ||
e429caa2 | 289 | get = size + extra_bytes - already_available; |
abe9ff32 | 290 | get = (char *) ROUNDUP ((char *)last_heap->end + get) |
e429caa2 | 291 | - (char *) last_heap->end; |
dcfdbac7 | 292 | |
e429caa2 KH |
293 | if ((*real_morecore) (get) != last_heap->end) |
294 | return 0; | |
295 | ||
91a211b5 | 296 | last_heap->end = (char *) last_heap->end + get; |
e429caa2 KH |
297 | } |
298 | ||
299 | return address; | |
300 | } | |
dcfdbac7 | 301 | |
abe9ff32 RS |
302 | /* Return unused heap space to the system |
303 | if there is a lot of unused space now. | |
304 | This can make the last heap smaller; | |
305 | it can also eliminate the last heap entirely. */ | |
306 | ||
dcfdbac7 | 307 | static void |
971de7fb | 308 | relinquish (void) |
dcfdbac7 | 309 | { |
e429caa2 | 310 | register heap_ptr h; |
8d31e373 | 311 | long excess = 0; |
e429caa2 | 312 | |
abe9ff32 RS |
313 | /* Add the amount of space beyond break_value |
314 | in all heaps which have extend beyond break_value at all. */ | |
315 | ||
e429caa2 KH |
316 | for (h = last_heap; h && break_value < h->end; h = h->prev) |
317 | { | |
318 | excess += (char *) h->end - (char *) ((break_value < h->bloc_start) | |
319 | ? h->bloc_start : break_value); | |
320 | } | |
321 | ||
322 | if (excess > extra_bytes * 2 && (*real_morecore) (0) == last_heap->end) | |
dcfdbac7 | 323 | { |
7516b7d5 RS |
324 | /* Keep extra_bytes worth of empty space. |
325 | And don't free anything unless we can free at least extra_bytes. */ | |
e429caa2 | 326 | excess -= extra_bytes; |
dcfdbac7 | 327 | |
e429caa2 KH |
328 | if ((char *)last_heap->end - (char *)last_heap->bloc_start <= excess) |
329 | { | |
47f13333 RS |
330 | /* This heap should have no blocs in it. */ |
331 | if (last_heap->first_bloc != NIL_BLOC | |
332 | || last_heap->last_bloc != NIL_BLOC) | |
1088b922 | 333 | emacs_abort (); |
47f13333 | 334 | |
abe9ff32 | 335 | /* Return the last heap, with its header, to the system. */ |
e429caa2 KH |
336 | excess = (char *)last_heap->end - (char *)last_heap->start; |
337 | last_heap = last_heap->prev; | |
338 | last_heap->next = NIL_HEAP; | |
339 | } | |
340 | else | |
341 | { | |
342 | excess = (char *) last_heap->end | |
abe9ff32 | 343 | - (char *) ROUNDUP ((char *)last_heap->end - excess); |
91a211b5 | 344 | last_heap->end = (char *) last_heap->end - excess; |
e429caa2 | 345 | } |
dcfdbac7 | 346 | |
e429caa2 | 347 | if ((*real_morecore) (- excess) == 0) |
21532667 KH |
348 | { |
349 | /* If the system didn't want that much memory back, adjust | |
350 | the end of the last heap to reflect that. This can occur | |
351 | if break_value is still within the original data segment. */ | |
91a211b5 | 352 | last_heap->end = (char *) last_heap->end + excess; |
21532667 KH |
353 | /* Make sure that the result of the adjustment is accurate. |
354 | It should be, for the else clause above; the other case, | |
355 | which returns the entire last heap to the system, seems | |
356 | unlikely to trigger this mode of failure. */ | |
357 | if (last_heap->end != (*real_morecore) (0)) | |
1088b922 | 358 | emacs_abort (); |
21532667 | 359 | } |
e429caa2 | 360 | } |
dcfdbac7 JB |
361 | } |
362 | \f | |
956ace37 JB |
363 | /* The meat - allocating, freeing, and relocating blocs. */ |
364 | ||
956ace37 | 365 | /* Find the bloc referenced by the address in PTR. Returns a pointer |
abe9ff32 | 366 | to that block. */ |
dcfdbac7 JB |
367 | |
368 | static bloc_ptr | |
971de7fb | 369 | find_bloc (POINTER *ptr) |
dcfdbac7 JB |
370 | { |
371 | register bloc_ptr p = first_bloc; | |
372 | ||
373 | while (p != NIL_BLOC) | |
374 | { | |
747d9d14 | 375 | /* Consistency check. Don't return inconsistent blocs. |
0d26e0b6 | 376 | Don't abort here, as callers might be expecting this, but |
747d9d14 JR |
377 | callers that always expect a bloc to be returned should abort |
378 | if one isn't to avoid a memory corruption bug that is | |
379 | difficult to track down. */ | |
dcfdbac7 JB |
380 | if (p->variable == ptr && p->data == *ptr) |
381 | return p; | |
382 | ||
383 | p = p->next; | |
384 | } | |
385 | ||
386 | return p; | |
387 | } | |
388 | ||
389 | /* Allocate a bloc of SIZE bytes and append it to the chain of blocs. | |
98b7fe02 JB |
390 | Returns a pointer to the new bloc, or zero if we couldn't allocate |
391 | memory for the new block. */ | |
dcfdbac7 JB |
392 | |
393 | static bloc_ptr | |
971de7fb | 394 | get_bloc (SIZE size) |
dcfdbac7 | 395 | { |
98b7fe02 | 396 | register bloc_ptr new_bloc; |
abe9ff32 | 397 | register heap_ptr heap; |
98b7fe02 | 398 | |
38182d90 | 399 | if (! (new_bloc = malloc (BLOC_PTR_SIZE)) |
e429caa2 | 400 | || ! (new_bloc->data = obtain (break_value, size))) |
98b7fe02 | 401 | { |
c2cd06e6 | 402 | free (new_bloc); |
98b7fe02 JB |
403 | |
404 | return 0; | |
405 | } | |
dcfdbac7 | 406 | |
91a211b5 | 407 | break_value = (char *) new_bloc->data + size; |
e429caa2 | 408 | |
dcfdbac7 JB |
409 | new_bloc->size = size; |
410 | new_bloc->next = NIL_BLOC; | |
8c7f1e35 | 411 | new_bloc->variable = (POINTER *) NIL; |
e429caa2 | 412 | new_bloc->new_data = 0; |
dcfdbac7 | 413 | |
abe9ff32 RS |
414 | /* Record in the heap that this space is in use. */ |
415 | heap = find_heap (new_bloc->data); | |
416 | heap->free = break_value; | |
417 | ||
47f13333 RS |
418 | /* Maintain the correspondence between heaps and blocs. */ |
419 | new_bloc->heap = heap; | |
420 | heap->last_bloc = new_bloc; | |
421 | if (heap->first_bloc == NIL_BLOC) | |
422 | heap->first_bloc = new_bloc; | |
423 | ||
abe9ff32 | 424 | /* Put this bloc on the doubly-linked list of blocs. */ |
dcfdbac7 JB |
425 | if (first_bloc) |
426 | { | |
427 | new_bloc->prev = last_bloc; | |
428 | last_bloc->next = new_bloc; | |
429 | last_bloc = new_bloc; | |
430 | } | |
431 | else | |
432 | { | |
433 | first_bloc = last_bloc = new_bloc; | |
434 | new_bloc->prev = NIL_BLOC; | |
435 | } | |
436 | ||
437 | return new_bloc; | |
438 | } | |
47f13333 | 439 | \f |
abe9ff32 RS |
440 | /* Calculate new locations of blocs in the list beginning with BLOC, |
441 | relocating it to start at ADDRESS, in heap HEAP. If enough space is | |
442 | not presently available in our reserve, call obtain for | |
177c0ea7 JB |
443 | more space. |
444 | ||
abe9ff32 RS |
445 | Store the new location of each bloc in its new_data field. |
446 | Do not touch the contents of blocs or break_value. */ | |
dcfdbac7 | 447 | |
e429caa2 | 448 | static int |
971de7fb | 449 | relocate_blocs (bloc_ptr bloc, heap_ptr heap, POINTER address) |
e429caa2 KH |
450 | { |
451 | register bloc_ptr b = bloc; | |
ad3bb3d2 | 452 | |
49f82b3d | 453 | /* No need to ever call this if arena is frozen, bug somewhere! */ |
177c0ea7 | 454 | if (r_alloc_freeze_level) |
1088b922 | 455 | emacs_abort (); |
49f82b3d | 456 | |
e429caa2 KH |
457 | while (b) |
458 | { | |
abe9ff32 RS |
459 | /* If bloc B won't fit within HEAP, |
460 | move to the next heap and try again. */ | |
91a211b5 | 461 | while (heap && (char *) address + b->size > (char *) heap->end) |
e429caa2 KH |
462 | { |
463 | heap = heap->next; | |
464 | if (heap == NIL_HEAP) | |
465 | break; | |
466 | address = heap->bloc_start; | |
467 | } | |
dcfdbac7 | 468 | |
abe9ff32 RS |
469 | /* If BLOC won't fit in any heap, |
470 | get enough new space to hold BLOC and all following blocs. */ | |
e429caa2 KH |
471 | if (heap == NIL_HEAP) |
472 | { | |
473 | register bloc_ptr tb = b; | |
474 | register SIZE s = 0; | |
475 | ||
abe9ff32 | 476 | /* Add up the size of all the following blocs. */ |
e429caa2 KH |
477 | while (tb != NIL_BLOC) |
478 | { | |
177c0ea7 | 479 | if (tb->variable) |
49f82b3d RS |
480 | s += tb->size; |
481 | ||
e429caa2 KH |
482 | tb = tb->next; |
483 | } | |
484 | ||
abe9ff32 RS |
485 | /* Get that space. */ |
486 | address = obtain (address, s); | |
487 | if (address == 0) | |
e429caa2 KH |
488 | return 0; |
489 | ||
490 | heap = last_heap; | |
491 | } | |
492 | ||
abe9ff32 RS |
493 | /* Record the new address of this bloc |
494 | and update where the next bloc can start. */ | |
e429caa2 | 495 | b->new_data = address; |
177c0ea7 | 496 | if (b->variable) |
91a211b5 | 497 | address = (char *) address + b->size; |
e429caa2 KH |
498 | b = b->next; |
499 | } | |
500 | ||
501 | return 1; | |
502 | } | |
47f13333 RS |
503 | \f |
504 | /* Update the records of which heaps contain which blocs, starting | |
505 | with heap HEAP and bloc BLOC. */ | |
506 | ||
507 | static void | |
971de7fb | 508 | update_heap_bloc_correspondence (bloc_ptr bloc, heap_ptr heap) |
abe9ff32 RS |
509 | { |
510 | register bloc_ptr b; | |
511 | ||
47f13333 RS |
512 | /* Initialize HEAP's status to reflect blocs before BLOC. */ |
513 | if (bloc != NIL_BLOC && bloc->prev != NIL_BLOC && bloc->prev->heap == heap) | |
514 | { | |
515 | /* The previous bloc is in HEAP. */ | |
516 | heap->last_bloc = bloc->prev; | |
91a211b5 | 517 | heap->free = (char *) bloc->prev->data + bloc->prev->size; |
47f13333 RS |
518 | } |
519 | else | |
520 | { | |
521 | /* HEAP contains no blocs before BLOC. */ | |
522 | heap->first_bloc = NIL_BLOC; | |
523 | heap->last_bloc = NIL_BLOC; | |
524 | heap->free = heap->bloc_start; | |
525 | } | |
526 | ||
abe9ff32 RS |
527 | /* Advance through blocs one by one. */ |
528 | for (b = bloc; b != NIL_BLOC; b = b->next) | |
529 | { | |
47f13333 RS |
530 | /* Advance through heaps, marking them empty, |
531 | till we get to the one that B is in. */ | |
abe9ff32 RS |
532 | while (heap) |
533 | { | |
534 | if (heap->bloc_start <= b->data && b->data <= heap->end) | |
535 | break; | |
536 | heap = heap->next; | |
47f13333 RS |
537 | /* We know HEAP is not null now, |
538 | because there has to be space for bloc B. */ | |
539 | heap->first_bloc = NIL_BLOC; | |
540 | heap->last_bloc = NIL_BLOC; | |
abe9ff32 RS |
541 | heap->free = heap->bloc_start; |
542 | } | |
47f13333 RS |
543 | |
544 | /* Update HEAP's status for bloc B. */ | |
91a211b5 | 545 | heap->free = (char *) b->data + b->size; |
47f13333 RS |
546 | heap->last_bloc = b; |
547 | if (heap->first_bloc == NIL_BLOC) | |
548 | heap->first_bloc = b; | |
549 | ||
550 | /* Record that B is in HEAP. */ | |
551 | b->heap = heap; | |
abe9ff32 RS |
552 | } |
553 | ||
554 | /* If there are any remaining heaps and no blocs left, | |
47f13333 | 555 | mark those heaps as empty. */ |
abe9ff32 RS |
556 | heap = heap->next; |
557 | while (heap) | |
558 | { | |
47f13333 RS |
559 | heap->first_bloc = NIL_BLOC; |
560 | heap->last_bloc = NIL_BLOC; | |
abe9ff32 RS |
561 | heap->free = heap->bloc_start; |
562 | heap = heap->next; | |
563 | } | |
564 | } | |
47f13333 | 565 | \f |
abe9ff32 RS |
566 | /* Resize BLOC to SIZE bytes. This relocates the blocs |
567 | that come after BLOC in memory. */ | |
568 | ||
e429caa2 | 569 | static int |
971de7fb | 570 | resize_bloc (bloc_ptr bloc, SIZE size) |
dcfdbac7 | 571 | { |
e429caa2 KH |
572 | register bloc_ptr b; |
573 | heap_ptr heap; | |
574 | POINTER address; | |
575 | SIZE old_size; | |
576 | ||
49f82b3d | 577 | /* No need to ever call this if arena is frozen, bug somewhere! */ |
177c0ea7 | 578 | if (r_alloc_freeze_level) |
1088b922 | 579 | emacs_abort (); |
49f82b3d | 580 | |
e429caa2 KH |
581 | if (bloc == NIL_BLOC || size == bloc->size) |
582 | return 1; | |
583 | ||
584 | for (heap = first_heap; heap != NIL_HEAP; heap = heap->next) | |
585 | { | |
586 | if (heap->bloc_start <= bloc->data && bloc->data <= heap->end) | |
587 | break; | |
588 | } | |
589 | ||
590 | if (heap == NIL_HEAP) | |
1088b922 | 591 | emacs_abort (); |
e429caa2 KH |
592 | |
593 | old_size = bloc->size; | |
594 | bloc->size = size; | |
595 | ||
abe9ff32 | 596 | /* Note that bloc could be moved into the previous heap. */ |
91a211b5 GM |
597 | address = (bloc->prev ? (char *) bloc->prev->data + bloc->prev->size |
598 | : (char *) first_heap->bloc_start); | |
e429caa2 KH |
599 | while (heap) |
600 | { | |
601 | if (heap->bloc_start <= address && address <= heap->end) | |
602 | break; | |
603 | heap = heap->prev; | |
604 | } | |
605 | ||
606 | if (! relocate_blocs (bloc, heap, address)) | |
607 | { | |
608 | bloc->size = old_size; | |
609 | return 0; | |
610 | } | |
611 | ||
612 | if (size > old_size) | |
613 | { | |
614 | for (b = last_bloc; b != bloc; b = b->prev) | |
615 | { | |
49f82b3d RS |
616 | if (!b->variable) |
617 | { | |
618 | b->size = 0; | |
619 | b->data = b->new_data; | |
177c0ea7 JB |
620 | } |
621 | else | |
49f82b3d | 622 | { |
78cef877 EZ |
623 | if (b->new_data != b->data) |
624 | memmove (b->new_data, b->data, b->size); | |
49f82b3d RS |
625 | *b->variable = b->data = b->new_data; |
626 | } | |
627 | } | |
628 | if (!bloc->variable) | |
629 | { | |
630 | bloc->size = 0; | |
631 | bloc->data = bloc->new_data; | |
632 | } | |
633 | else | |
634 | { | |
78cef877 EZ |
635 | if (bloc->new_data != bloc->data) |
636 | memmove (bloc->new_data, bloc->data, old_size); | |
3ce2f8ac | 637 | memset ((char *) bloc->new_data + old_size, 0, size - old_size); |
49f82b3d | 638 | *bloc->variable = bloc->data = bloc->new_data; |
e429caa2 | 639 | } |
e429caa2 KH |
640 | } |
641 | else | |
dcfdbac7 | 642 | { |
ad3bb3d2 JB |
643 | for (b = bloc; b != NIL_BLOC; b = b->next) |
644 | { | |
49f82b3d RS |
645 | if (!b->variable) |
646 | { | |
647 | b->size = 0; | |
648 | b->data = b->new_data; | |
177c0ea7 JB |
649 | } |
650 | else | |
49f82b3d | 651 | { |
78cef877 EZ |
652 | if (b->new_data != b->data) |
653 | memmove (b->new_data, b->data, b->size); | |
49f82b3d RS |
654 | *b->variable = b->data = b->new_data; |
655 | } | |
ad3bb3d2 | 656 | } |
ad3bb3d2 | 657 | } |
dcfdbac7 | 658 | |
47f13333 | 659 | update_heap_bloc_correspondence (bloc, heap); |
abe9ff32 | 660 | |
91a211b5 GM |
661 | break_value = (last_bloc ? (char *) last_bloc->data + last_bloc->size |
662 | : (char *) first_heap->bloc_start); | |
e429caa2 KH |
663 | return 1; |
664 | } | |
47f13333 | 665 | \f |
abe9ff32 RS |
666 | /* Free BLOC from the chain of blocs, relocating any blocs above it. |
667 | This may return space to the system. */ | |
dcfdbac7 JB |
668 | |
669 | static void | |
971de7fb | 670 | free_bloc (bloc_ptr bloc) |
dcfdbac7 | 671 | { |
47f13333 | 672 | heap_ptr heap = bloc->heap; |
36c46f8e | 673 | heap_ptr h; |
47f13333 | 674 | |
49f82b3d RS |
675 | if (r_alloc_freeze_level) |
676 | { | |
677 | bloc->variable = (POINTER *) NIL; | |
678 | return; | |
679 | } | |
177c0ea7 | 680 | |
e429caa2 KH |
681 | resize_bloc (bloc, 0); |
682 | ||
dcfdbac7 JB |
683 | if (bloc == first_bloc && bloc == last_bloc) |
684 | { | |
685 | first_bloc = last_bloc = NIL_BLOC; | |
686 | } | |
687 | else if (bloc == last_bloc) | |
688 | { | |
689 | last_bloc = bloc->prev; | |
690 | last_bloc->next = NIL_BLOC; | |
691 | } | |
692 | else if (bloc == first_bloc) | |
693 | { | |
694 | first_bloc = bloc->next; | |
695 | first_bloc->prev = NIL_BLOC; | |
dcfdbac7 JB |
696 | } |
697 | else | |
698 | { | |
699 | bloc->next->prev = bloc->prev; | |
700 | bloc->prev->next = bloc->next; | |
dcfdbac7 JB |
701 | } |
702 | ||
36c46f8e EZ |
703 | /* Sometimes, 'heap' obtained from bloc->heap above is not really a |
704 | 'heap' structure. It can even be beyond the current break point, | |
705 | which will cause crashes when we dereference it below (see | |
706 | bug#12242). Evidently, the reason is bloc allocations done while | |
707 | use_relocatable_buffers was non-positive, because additional | |
708 | memory we get then is not recorded in the heaps we manage. If | |
709 | bloc->heap records such a "heap", we cannot (and don't need to) | |
710 | update its records. So we validate the 'heap' value by making | |
711 | sure it is one of the heaps we manage via the heaps linked list, | |
712 | and don't touch a 'heap' that isn't found there. This avoids | |
713 | accessing memory we know nothing about. */ | |
714 | for (h = first_heap; h != NIL_HEAP; h = h->next) | |
715 | if (heap == h) | |
716 | break; | |
717 | ||
718 | if (h) | |
47f13333 | 719 | { |
36c46f8e EZ |
720 | /* Update the records of which blocs are in HEAP. */ |
721 | if (heap->first_bloc == bloc) | |
722 | { | |
723 | if (bloc->next != 0 && bloc->next->heap == heap) | |
724 | heap->first_bloc = bloc->next; | |
725 | else | |
726 | heap->first_bloc = heap->last_bloc = NIL_BLOC; | |
727 | } | |
728 | if (heap->last_bloc == bloc) | |
729 | { | |
730 | if (bloc->prev != 0 && bloc->prev->heap == heap) | |
731 | heap->last_bloc = bloc->prev; | |
732 | else | |
733 | heap->first_bloc = heap->last_bloc = NIL_BLOC; | |
734 | } | |
47f13333 RS |
735 | } |
736 | ||
e429caa2 | 737 | relinquish (); |
dcfdbac7 JB |
738 | free (bloc); |
739 | } | |
740 | \f | |
956ace37 JB |
741 | /* Interface routines. */ |
742 | ||
98b7fe02 | 743 | /* Obtain SIZE bytes of storage from the free pool, or the system, as |
2c46d29f | 744 | necessary. If relocatable blocs are in use, this means relocating |
98b7fe02 JB |
745 | them. This function gets plugged into the GNU malloc's __morecore |
746 | hook. | |
747 | ||
7516b7d5 RS |
748 | We provide hysteresis, never relocating by less than extra_bytes. |
749 | ||
98b7fe02 JB |
750 | If we're out of memory, we should return zero, to imitate the other |
751 | __morecore hook values - in particular, __default_morecore in the | |
752 | GNU malloc package. */ | |
dcfdbac7 | 753 | |
3539f31f | 754 | static POINTER |
971de7fb | 755 | r_alloc_sbrk (long int size) |
dcfdbac7 | 756 | { |
e429caa2 KH |
757 | register bloc_ptr b; |
758 | POINTER address; | |
dcfdbac7 | 759 | |
44d3dec0 RS |
760 | if (! r_alloc_initialized) |
761 | r_alloc_init (); | |
762 | ||
e8a02204 | 763 | if (use_relocatable_buffers <= 0) |
bbc60227 | 764 | return (*real_morecore) (size); |
dcfdbac7 | 765 | |
e429caa2 KH |
766 | if (size == 0) |
767 | return virtual_break_value; | |
7516b7d5 | 768 | |
e429caa2 | 769 | if (size > 0) |
dcfdbac7 | 770 | { |
abe9ff32 RS |
771 | /* Allocate a page-aligned space. GNU malloc would reclaim an |
772 | extra space if we passed an unaligned one. But we could | |
8e6208c5 | 773 | not always find a space which is contiguous to the previous. */ |
e429caa2 KH |
774 | POINTER new_bloc_start; |
775 | heap_ptr h = first_heap; | |
abe9ff32 | 776 | SIZE get = ROUNDUP (size); |
7516b7d5 | 777 | |
abe9ff32 | 778 | address = (POINTER) ROUNDUP (virtual_break_value); |
e429caa2 | 779 | |
abe9ff32 RS |
780 | /* Search the list upward for a heap which is large enough. */ |
781 | while ((char *) h->end < (char *) MEM_ROUNDUP ((char *)address + get)) | |
e429caa2 KH |
782 | { |
783 | h = h->next; | |
784 | if (h == NIL_HEAP) | |
785 | break; | |
abe9ff32 | 786 | address = (POINTER) ROUNDUP (h->start); |
e429caa2 KH |
787 | } |
788 | ||
abe9ff32 | 789 | /* If not found, obtain more space. */ |
e429caa2 KH |
790 | if (h == NIL_HEAP) |
791 | { | |
792 | get += extra_bytes + page_size; | |
793 | ||
49f82b3d | 794 | if (! obtain (address, get)) |
e429caa2 | 795 | return 0; |
98b7fe02 | 796 | |
e429caa2 | 797 | if (first_heap == last_heap) |
abe9ff32 | 798 | address = (POINTER) ROUNDUP (virtual_break_value); |
e429caa2 | 799 | else |
abe9ff32 | 800 | address = (POINTER) ROUNDUP (last_heap->start); |
e429caa2 KH |
801 | h = last_heap; |
802 | } | |
803 | ||
abe9ff32 | 804 | new_bloc_start = (POINTER) MEM_ROUNDUP ((char *)address + get); |
e429caa2 KH |
805 | |
806 | if (first_heap->bloc_start < new_bloc_start) | |
807 | { | |
49f82b3d | 808 | /* This is no clean solution - no idea how to do it better. */ |
177c0ea7 | 809 | if (r_alloc_freeze_level) |
49f82b3d RS |
810 | return NIL; |
811 | ||
812 | /* There is a bug here: if the above obtain call succeeded, but the | |
813 | relocate_blocs call below does not succeed, we need to free | |
814 | the memory that we got with obtain. */ | |
815 | ||
abe9ff32 | 816 | /* Move all blocs upward. */ |
49f82b3d | 817 | if (! relocate_blocs (first_bloc, h, new_bloc_start)) |
e429caa2 KH |
818 | return 0; |
819 | ||
820 | /* Note that (POINTER)(h+1) <= new_bloc_start since | |
821 | get >= page_size, so the following does not destroy the heap | |
abe9ff32 | 822 | header. */ |
e429caa2 KH |
823 | for (b = last_bloc; b != NIL_BLOC; b = b->prev) |
824 | { | |
78cef877 EZ |
825 | if (b->new_data != b->data) |
826 | memmove (b->new_data, b->data, b->size); | |
e429caa2 KH |
827 | *b->variable = b->data = b->new_data; |
828 | } | |
829 | ||
830 | h->bloc_start = new_bloc_start; | |
abe9ff32 | 831 | |
47f13333 | 832 | update_heap_bloc_correspondence (first_bloc, h); |
e429caa2 | 833 | } |
e429caa2 KH |
834 | if (h != first_heap) |
835 | { | |
836 | /* Give up managing heaps below the one the new | |
abe9ff32 | 837 | virtual_break_value points to. */ |
e429caa2 KH |
838 | first_heap->prev = NIL_HEAP; |
839 | first_heap->next = h->next; | |
840 | first_heap->start = h->start; | |
841 | first_heap->end = h->end; | |
abe9ff32 | 842 | first_heap->free = h->free; |
47f13333 RS |
843 | first_heap->first_bloc = h->first_bloc; |
844 | first_heap->last_bloc = h->last_bloc; | |
e429caa2 KH |
845 | first_heap->bloc_start = h->bloc_start; |
846 | ||
847 | if (first_heap->next) | |
848 | first_heap->next->prev = first_heap; | |
849 | else | |
850 | last_heap = first_heap; | |
851 | } | |
852 | ||
72af86bd | 853 | memset (address, 0, size); |
dcfdbac7 | 854 | } |
e429caa2 | 855 | else /* size < 0 */ |
dcfdbac7 | 856 | { |
e429caa2 KH |
857 | SIZE excess = (char *)first_heap->bloc_start |
858 | - ((char *)virtual_break_value + size); | |
859 | ||
860 | address = virtual_break_value; | |
861 | ||
862 | if (r_alloc_freeze_level == 0 && excess > 2 * extra_bytes) | |
863 | { | |
864 | excess -= extra_bytes; | |
865 | first_heap->bloc_start | |
47f13333 | 866 | = (POINTER) MEM_ROUNDUP ((char *)first_heap->bloc_start - excess); |
e429caa2 | 867 | |
abe9ff32 | 868 | relocate_blocs (first_bloc, first_heap, first_heap->bloc_start); |
7516b7d5 | 869 | |
e429caa2 KH |
870 | for (b = first_bloc; b != NIL_BLOC; b = b->next) |
871 | { | |
78cef877 EZ |
872 | if (b->new_data != b->data) |
873 | memmove (b->new_data, b->data, b->size); | |
e429caa2 KH |
874 | *b->variable = b->data = b->new_data; |
875 | } | |
876 | } | |
877 | ||
878 | if ((char *)virtual_break_value + size < (char *)first_heap->start) | |
879 | { | |
880 | /* We found an additional space below the first heap */ | |
881 | first_heap->start = (POINTER) ((char *)virtual_break_value + size); | |
882 | } | |
dcfdbac7 JB |
883 | } |
884 | ||
e429caa2 | 885 | virtual_break_value = (POINTER) ((char *)address + size); |
47f13333 | 886 | break_value = (last_bloc |
91a211b5 GM |
887 | ? (char *) last_bloc->data + last_bloc->size |
888 | : (char *) first_heap->bloc_start); | |
e429caa2 | 889 | if (size < 0) |
abe9ff32 | 890 | relinquish (); |
7516b7d5 | 891 | |
e429caa2 | 892 | return address; |
dcfdbac7 JB |
893 | } |
894 | ||
0a58f946 | 895 | |
dcfdbac7 JB |
896 | /* Allocate a relocatable bloc of storage of size SIZE. A pointer to |
897 | the data is returned in *PTR. PTR is thus the address of some variable | |
98b7fe02 JB |
898 | which will use the data area. |
899 | ||
49f82b3d | 900 | The allocation of 0 bytes is valid. |
f96f2c5b JB |
901 | In case r_alloc_freeze_level is set, a best fit of unused blocs could be |
902 | done before allocating a new area. Not yet done. | |
49f82b3d | 903 | |
98b7fe02 JB |
904 | If we can't allocate the necessary memory, set *PTR to zero, and |
905 | return zero. */ | |
dcfdbac7 JB |
906 | |
907 | POINTER | |
971de7fb | 908 | r_alloc (POINTER *ptr, SIZE size) |
dcfdbac7 JB |
909 | { |
910 | register bloc_ptr new_bloc; | |
911 | ||
2c46d29f RS |
912 | if (! r_alloc_initialized) |
913 | r_alloc_init (); | |
914 | ||
abe9ff32 | 915 | new_bloc = get_bloc (MEM_ROUNDUP (size)); |
98b7fe02 JB |
916 | if (new_bloc) |
917 | { | |
918 | new_bloc->variable = ptr; | |
919 | *ptr = new_bloc->data; | |
920 | } | |
921 | else | |
922 | *ptr = 0; | |
dcfdbac7 JB |
923 | |
924 | return *ptr; | |
925 | } | |
926 | ||
2c46d29f RS |
927 | /* Free a bloc of relocatable storage whose data is pointed to by PTR. |
928 | Store 0 in *PTR to show there's no block allocated. */ | |
dcfdbac7 JB |
929 | |
930 | void | |
971de7fb | 931 | r_alloc_free (register POINTER *ptr) |
dcfdbac7 JB |
932 | { |
933 | register bloc_ptr dead_bloc; | |
934 | ||
44d3dec0 RS |
935 | if (! r_alloc_initialized) |
936 | r_alloc_init (); | |
937 | ||
dcfdbac7 JB |
938 | dead_bloc = find_bloc (ptr); |
939 | if (dead_bloc == NIL_BLOC) | |
1088b922 | 940 | emacs_abort (); /* Double free? PTR not originally used to allocate? */ |
dcfdbac7 JB |
941 | |
942 | free_bloc (dead_bloc); | |
2c46d29f | 943 | *ptr = 0; |
719b242f | 944 | |
d5179acc | 945 | #ifdef emacs |
719b242f | 946 | refill_memory_reserve (); |
d5179acc | 947 | #endif |
dcfdbac7 JB |
948 | } |
949 | ||
16a5c729 | 950 | /* Given a pointer at address PTR to relocatable data, resize it to SIZE. |
98b7fe02 JB |
951 | Do this by shifting all blocks above this one up in memory, unless |
952 | SIZE is less than or equal to the current bloc size, in which case | |
953 | do nothing. | |
dcfdbac7 | 954 | |
f96f2c5b | 955 | In case r_alloc_freeze_level is set, a new bloc is allocated, and the |
8e6208c5 | 956 | memory copied to it. Not very efficient. We could traverse the |
49f82b3d RS |
957 | bloc_list for a best fit of free blocs first. |
958 | ||
98b7fe02 JB |
959 | Change *PTR to reflect the new bloc, and return this value. |
960 | ||
961 | If more memory cannot be allocated, then leave *PTR unchanged, and | |
962 | return zero. */ | |
dcfdbac7 JB |
963 | |
964 | POINTER | |
971de7fb | 965 | r_re_alloc (POINTER *ptr, SIZE size) |
dcfdbac7 | 966 | { |
16a5c729 | 967 | register bloc_ptr bloc; |
dcfdbac7 | 968 | |
44d3dec0 RS |
969 | if (! r_alloc_initialized) |
970 | r_alloc_init (); | |
971 | ||
49f82b3d RS |
972 | if (!*ptr) |
973 | return r_alloc (ptr, size); | |
177c0ea7 | 974 | if (!size) |
49f82b3d RS |
975 | { |
976 | r_alloc_free (ptr); | |
977 | return r_alloc (ptr, 0); | |
978 | } | |
979 | ||
16a5c729 JB |
980 | bloc = find_bloc (ptr); |
981 | if (bloc == NIL_BLOC) | |
1088b922 | 982 | emacs_abort (); /* Already freed? PTR not originally used to allocate? */ |
dcfdbac7 | 983 | |
177c0ea7 | 984 | if (size < bloc->size) |
49f82b3d RS |
985 | { |
986 | /* Wouldn't it be useful to actually resize the bloc here? */ | |
987 | /* I think so too, but not if it's too expensive... */ | |
177c0ea7 JB |
988 | if ((bloc->size - MEM_ROUNDUP (size) >= page_size) |
989 | && r_alloc_freeze_level == 0) | |
49f82b3d RS |
990 | { |
991 | resize_bloc (bloc, MEM_ROUNDUP (size)); | |
992 | /* Never mind if this fails, just do nothing... */ | |
993 | /* It *should* be infallible! */ | |
994 | } | |
995 | } | |
996 | else if (size > bloc->size) | |
997 | { | |
998 | if (r_alloc_freeze_level) | |
999 | { | |
1000 | bloc_ptr new_bloc; | |
1001 | new_bloc = get_bloc (MEM_ROUNDUP (size)); | |
1002 | if (new_bloc) | |
1003 | { | |
1004 | new_bloc->variable = ptr; | |
1005 | *ptr = new_bloc->data; | |
1006 | bloc->variable = (POINTER *) NIL; | |
1007 | } | |
1008 | else | |
1009 | return NIL; | |
1010 | } | |
177c0ea7 | 1011 | else |
49f82b3d RS |
1012 | { |
1013 | if (! resize_bloc (bloc, MEM_ROUNDUP (size))) | |
1014 | return NIL; | |
1015 | } | |
1016 | } | |
dcfdbac7 JB |
1017 | return *ptr; |
1018 | } | |
81bd58e8 | 1019 | |
dec41418 RS |
1020 | |
1021 | #if defined (emacs) && defined (DOUG_LEA_MALLOC) | |
1022 | ||
1023 | /* Reinitialize the morecore hook variables after restarting a dumped | |
1024 | Emacs. This is needed when using Doug Lea's malloc from GNU libc. */ | |
1025 | void | |
971de7fb | 1026 | r_alloc_reinit (void) |
dec41418 RS |
1027 | { |
1028 | /* Only do this if the hook has been reset, so that we don't get an | |
1029 | infinite loop, in case Emacs was linked statically. */ | |
1030 | if (__morecore != r_alloc_sbrk) | |
1031 | { | |
1032 | real_morecore = __morecore; | |
1033 | __morecore = r_alloc_sbrk; | |
1034 | } | |
1035 | } | |
0a58f946 GM |
1036 | |
1037 | #endif /* emacs && DOUG_LEA_MALLOC */ | |
dec41418 | 1038 | |
e429caa2 | 1039 | #ifdef DEBUG |
0a58f946 | 1040 | |
e429caa2 KH |
1041 | #include <assert.h> |
1042 | ||
44d3dec0 | 1043 | void |
268c2c36 | 1044 | r_alloc_check (void) |
e429caa2 | 1045 | { |
6d16dd06 RS |
1046 | int found = 0; |
1047 | heap_ptr h, ph = 0; | |
1048 | bloc_ptr b, pb = 0; | |
1049 | ||
1050 | if (!r_alloc_initialized) | |
1051 | return; | |
1052 | ||
1053 | assert (first_heap); | |
1054 | assert (last_heap->end <= (POINTER) sbrk (0)); | |
1055 | assert ((POINTER) first_heap < first_heap->start); | |
1056 | assert (first_heap->start <= virtual_break_value); | |
1057 | assert (virtual_break_value <= first_heap->end); | |
1058 | ||
1059 | for (h = first_heap; h; h = h->next) | |
1060 | { | |
1061 | assert (h->prev == ph); | |
1062 | assert ((POINTER) ROUNDUP (h->end) == h->end); | |
40f3f04b RS |
1063 | #if 0 /* ??? The code in ralloc.c does not really try to ensure |
1064 | the heap start has any sort of alignment. | |
1065 | Perhaps it should. */ | |
6d16dd06 | 1066 | assert ((POINTER) MEM_ROUNDUP (h->start) == h->start); |
40f3f04b | 1067 | #endif |
6d16dd06 RS |
1068 | assert ((POINTER) MEM_ROUNDUP (h->bloc_start) == h->bloc_start); |
1069 | assert (h->start <= h->bloc_start && h->bloc_start <= h->end); | |
1070 | ||
1071 | if (ph) | |
1072 | { | |
1073 | assert (ph->end < h->start); | |
1074 | assert (h->start <= (POINTER)h && (POINTER)(h+1) <= h->bloc_start); | |
1075 | } | |
1076 | ||
1077 | if (h->bloc_start <= break_value && break_value <= h->end) | |
1078 | found = 1; | |
1079 | ||
1080 | ph = h; | |
1081 | } | |
1082 | ||
1083 | assert (found); | |
1084 | assert (last_heap == ph); | |
1085 | ||
1086 | for (b = first_bloc; b; b = b->next) | |
1087 | { | |
1088 | assert (b->prev == pb); | |
1089 | assert ((POINTER) MEM_ROUNDUP (b->data) == b->data); | |
1090 | assert ((SIZE) MEM_ROUNDUP (b->size) == b->size); | |
1091 | ||
1092 | ph = 0; | |
1093 | for (h = first_heap; h; h = h->next) | |
1094 | { | |
1095 | if (h->bloc_start <= b->data && b->data + b->size <= h->end) | |
1096 | break; | |
1097 | ph = h; | |
1098 | } | |
1099 | ||
1100 | assert (h); | |
1101 | ||
1102 | if (pb && pb->data + pb->size != b->data) | |
1103 | { | |
1104 | assert (ph && b->data == h->bloc_start); | |
1105 | while (ph) | |
1106 | { | |
1107 | if (ph->bloc_start <= pb->data | |
1108 | && pb->data + pb->size <= ph->end) | |
1109 | { | |
1110 | assert (pb->data + pb->size + b->size > ph->end); | |
1111 | break; | |
1112 | } | |
1113 | else | |
1114 | { | |
1115 | assert (ph->bloc_start + b->size > ph->end); | |
1116 | } | |
1117 | ph = ph->prev; | |
1118 | } | |
1119 | } | |
1120 | pb = b; | |
1121 | } | |
1122 | ||
1123 | assert (last_bloc == pb); | |
1124 | ||
1125 | if (last_bloc) | |
1126 | assert (last_bloc->data + last_bloc->size == break_value); | |
1127 | else | |
1128 | assert (first_heap->bloc_start == break_value); | |
e429caa2 | 1129 | } |
0a58f946 | 1130 | |
e429caa2 | 1131 | #endif /* DEBUG */ |
0a58f946 | 1132 | |
baae5c2d JR |
1133 | /* Update the internal record of which variable points to some data to NEW. |
1134 | Used by buffer-swap-text in Emacs to restore consistency after it | |
1135 | swaps the buffer text between two buffer objects. The OLD pointer | |
1136 | is checked to ensure that memory corruption does not occur due to | |
1137 | misuse. */ | |
1138 | void | |
971de7fb | 1139 | r_alloc_reset_variable (POINTER *old, POINTER *new) |
baae5c2d JR |
1140 | { |
1141 | bloc_ptr bloc = first_bloc; | |
1142 | ||
1143 | /* Find the bloc that corresponds to the data pointed to by pointer. | |
1144 | find_bloc cannot be used, as it has internal consistency checks | |
0d26e0b6 | 1145 | which fail when the variable needs resetting. */ |
baae5c2d JR |
1146 | while (bloc != NIL_BLOC) |
1147 | { | |
1148 | if (bloc->data == *new) | |
1149 | break; | |
1150 | ||
1151 | bloc = bloc->next; | |
1152 | } | |
1153 | ||
1154 | if (bloc == NIL_BLOC || bloc->variable != old) | |
1088b922 | 1155 | emacs_abort (); /* Already freed? OLD not originally used to allocate? */ |
baae5c2d JR |
1156 | |
1157 | /* Update variable to point to the new location. */ | |
1158 | bloc->variable = new; | |
1159 | } | |
0a58f946 | 1160 | |
52c55cc7 EZ |
1161 | void |
1162 | r_alloc_inhibit_buffer_relocation (int inhibit) | |
1163 | { | |
e8a02204 EZ |
1164 | if (use_relocatable_buffers > 1) |
1165 | use_relocatable_buffers = 1; | |
291d430f | 1166 | if (inhibit) |
291d430f | 1167 | use_relocatable_buffers--; |
e8a02204 EZ |
1168 | else if (use_relocatable_buffers < 1) |
1169 | use_relocatable_buffers++; | |
52c55cc7 EZ |
1170 | } |
1171 | ||
0a58f946 GM |
1172 | \f |
1173 | /*********************************************************************** | |
1174 | Initialization | |
1175 | ***********************************************************************/ | |
1176 | ||
0a58f946 GM |
1177 | /* Initialize various things for memory allocation. */ |
1178 | ||
1179 | static void | |
971de7fb | 1180 | r_alloc_init (void) |
0a58f946 GM |
1181 | { |
1182 | if (r_alloc_initialized) | |
1183 | return; | |
0a58f946 | 1184 | r_alloc_initialized = 1; |
177c0ea7 | 1185 | |
a2c23c92 DL |
1186 | page_size = PAGE; |
1187 | #ifndef SYSTEM_MALLOC | |
0a58f946 GM |
1188 | real_morecore = __morecore; |
1189 | __morecore = r_alloc_sbrk; | |
1190 | ||
1191 | first_heap = last_heap = &heap_base; | |
1192 | first_heap->next = first_heap->prev = NIL_HEAP; | |
1193 | first_heap->start = first_heap->bloc_start | |
1194 | = virtual_break_value = break_value = (*real_morecore) (0); | |
1195 | if (break_value == NIL) | |
1088b922 | 1196 | emacs_abort (); |
0a58f946 | 1197 | |
0a58f946 | 1198 | extra_bytes = ROUNDUP (50000); |
a2c23c92 | 1199 | #endif |
0a58f946 GM |
1200 | |
1201 | #ifdef DOUG_LEA_MALLOC | |
4d7e6e51 | 1202 | block_input (); |
1673df2e | 1203 | mallopt (M_TOP_PAD, 64 * 4096); |
4d7e6e51 | 1204 | unblock_input (); |
0a58f946 | 1205 | #else |
a2c23c92 | 1206 | #ifndef SYSTEM_MALLOC |
45ba16c7 EZ |
1207 | /* Give GNU malloc's morecore some hysteresis so that we move all |
1208 | the relocatable blocks much less often. The number used to be | |
1209 | 64, but alloc.c would override that with 32 in code that was | |
1210 | removed when SYNC_INPUT became the only input handling mode. | |
9b318728 | 1211 | That code was conditioned on !DOUG_LEA_MALLOC, so the call to |
45ba16c7 EZ |
1212 | mallopt above is left unchanged. (Actually, I think there's no |
1213 | system nowadays that uses DOUG_LEA_MALLOC and also uses | |
1214 | REL_ALLOC.) */ | |
1215 | __malloc_extra_blocks = 32; | |
0a58f946 | 1216 | #endif |
a2c23c92 | 1217 | #endif |
0a58f946 | 1218 | |
5ad25b24 | 1219 | #ifndef SYSTEM_MALLOC |
0a58f946 GM |
1220 | first_heap->end = (POINTER) ROUNDUP (first_heap->start); |
1221 | ||
1222 | /* The extra call to real_morecore guarantees that the end of the | |
1223 | address space is a multiple of page_size, even if page_size is | |
1224 | not really the page size of the system running the binary in | |
1225 | which page_size is stored. This allows a binary to be built on a | |
1226 | system with one page size and run on a system with a smaller page | |
1227 | size. */ | |
91a211b5 | 1228 | (*real_morecore) ((char *) first_heap->end - (char *) first_heap->start); |
0a58f946 GM |
1229 | |
1230 | /* Clear the rest of the last page; this memory is in our address space | |
1231 | even though it is after the sbrk value. */ | |
1232 | /* Doubly true, with the additional call that explicitly adds the | |
1233 | rest of that page to the address space. */ | |
72af86bd AS |
1234 | memset (first_heap->start, 0, |
1235 | (char *) first_heap->end - (char *) first_heap->start); | |
0a58f946 | 1236 | virtual_break_value = break_value = first_heap->bloc_start = first_heap->end; |
a2c23c92 | 1237 | #endif |
177c0ea7 | 1238 | |
0a58f946 GM |
1239 | use_relocatable_buffers = 1; |
1240 | } |