Commit | Line | Data |
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177c0ea7 | 1 | /* Block-relocating memory allocator. |
ab422c4d | 2 | Copyright (C) 1993, 1995, 2000-2013 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. */ |
62aba0d4 | 75 | POINTER (*real_morecore) (ptrdiff_t); |
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 ()) |
62aba0d4 | 94 | #define ROUNDUP(size) (((size_t) (size) + page_size - 1) \ |
2d7d1608 | 95 | & ~((size_t)(page_size - 1))) |
e429caa2 | 96 | |
5e617bc2 | 97 | #define MEM_ALIGN sizeof (double) |
62aba0d4 | 98 | #define MEM_ROUNDUP(addr) (((size_t)(addr) + MEM_ALIGN - 1) \ |
2d7d1608 | 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 | |
62aba0d4 | 105 | extern POINTER (*__morecore) (ptrdiff_t); |
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; |
62aba0d4 | 311 | ptrdiff_t 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 | { | |
508f51f5 EZ |
330 | heap_ptr lh_prev; |
331 | ||
98daa893 EZ |
332 | /* This heap should have no blocs in it. If it does, we |
333 | cannot return it to the system. */ | |
47f13333 RS |
334 | if (last_heap->first_bloc != NIL_BLOC |
335 | || last_heap->last_bloc != NIL_BLOC) | |
98daa893 | 336 | return; |
47f13333 | 337 | |
abe9ff32 | 338 | /* Return the last heap, with its header, to the system. */ |
e429caa2 | 339 | excess = (char *)last_heap->end - (char *)last_heap->start; |
508f51f5 EZ |
340 | lh_prev = last_heap->prev; |
341 | /* If the system doesn't want that much memory back, leave | |
342 | last_heap unaltered to reflect that. This can occur if | |
343 | break_value is still within the original data segment. */ | |
344 | if ((*real_morecore) (- excess) != 0) | |
345 | { | |
346 | last_heap = lh_prev; | |
347 | last_heap->next = NIL_HEAP; | |
348 | } | |
e429caa2 KH |
349 | } |
350 | else | |
351 | { | |
352 | excess = (char *) last_heap->end | |
abe9ff32 | 353 | - (char *) ROUNDUP ((char *)last_heap->end - excess); |
508f51f5 EZ |
354 | /* If the system doesn't want that much memory back, leave |
355 | the end of the last heap unchanged to reflect that. This | |
356 | can occur if break_value is still within the original | |
357 | data segment. */ | |
358 | if ((*real_morecore) (- excess) != 0) | |
359 | last_heap->end = (char *) last_heap->end - excess; | |
21532667 | 360 | } |
e429caa2 | 361 | } |
dcfdbac7 JB |
362 | } |
363 | \f | |
956ace37 JB |
364 | /* The meat - allocating, freeing, and relocating blocs. */ |
365 | ||
956ace37 | 366 | /* Find the bloc referenced by the address in PTR. Returns a pointer |
abe9ff32 | 367 | to that block. */ |
dcfdbac7 JB |
368 | |
369 | static bloc_ptr | |
971de7fb | 370 | find_bloc (POINTER *ptr) |
dcfdbac7 JB |
371 | { |
372 | register bloc_ptr p = first_bloc; | |
373 | ||
374 | while (p != NIL_BLOC) | |
375 | { | |
747d9d14 | 376 | /* Consistency check. Don't return inconsistent blocs. |
0d26e0b6 | 377 | Don't abort here, as callers might be expecting this, but |
747d9d14 JR |
378 | callers that always expect a bloc to be returned should abort |
379 | if one isn't to avoid a memory corruption bug that is | |
380 | difficult to track down. */ | |
dcfdbac7 JB |
381 | if (p->variable == ptr && p->data == *ptr) |
382 | return p; | |
383 | ||
384 | p = p->next; | |
385 | } | |
386 | ||
387 | return p; | |
388 | } | |
389 | ||
390 | /* Allocate a bloc of SIZE bytes and append it to the chain of blocs. | |
98b7fe02 JB |
391 | Returns a pointer to the new bloc, or zero if we couldn't allocate |
392 | memory for the new block. */ | |
dcfdbac7 JB |
393 | |
394 | static bloc_ptr | |
971de7fb | 395 | get_bloc (SIZE size) |
dcfdbac7 | 396 | { |
98b7fe02 | 397 | register bloc_ptr new_bloc; |
abe9ff32 | 398 | register heap_ptr heap; |
98b7fe02 | 399 | |
38182d90 | 400 | if (! (new_bloc = malloc (BLOC_PTR_SIZE)) |
e429caa2 | 401 | || ! (new_bloc->data = obtain (break_value, size))) |
98b7fe02 | 402 | { |
c2cd06e6 | 403 | free (new_bloc); |
98b7fe02 JB |
404 | |
405 | return 0; | |
406 | } | |
dcfdbac7 | 407 | |
91a211b5 | 408 | break_value = (char *) new_bloc->data + size; |
e429caa2 | 409 | |
dcfdbac7 JB |
410 | new_bloc->size = size; |
411 | new_bloc->next = NIL_BLOC; | |
8c7f1e35 | 412 | new_bloc->variable = (POINTER *) NIL; |
e429caa2 | 413 | new_bloc->new_data = 0; |
dcfdbac7 | 414 | |
abe9ff32 RS |
415 | /* Record in the heap that this space is in use. */ |
416 | heap = find_heap (new_bloc->data); | |
417 | heap->free = break_value; | |
418 | ||
47f13333 RS |
419 | /* Maintain the correspondence between heaps and blocs. */ |
420 | new_bloc->heap = heap; | |
421 | heap->last_bloc = new_bloc; | |
422 | if (heap->first_bloc == NIL_BLOC) | |
423 | heap->first_bloc = new_bloc; | |
424 | ||
abe9ff32 | 425 | /* Put this bloc on the doubly-linked list of blocs. */ |
dcfdbac7 JB |
426 | if (first_bloc) |
427 | { | |
428 | new_bloc->prev = last_bloc; | |
429 | last_bloc->next = new_bloc; | |
430 | last_bloc = new_bloc; | |
431 | } | |
432 | else | |
433 | { | |
434 | first_bloc = last_bloc = new_bloc; | |
435 | new_bloc->prev = NIL_BLOC; | |
436 | } | |
437 | ||
438 | return new_bloc; | |
439 | } | |
47f13333 | 440 | \f |
abe9ff32 RS |
441 | /* Calculate new locations of blocs in the list beginning with BLOC, |
442 | relocating it to start at ADDRESS, in heap HEAP. If enough space is | |
443 | not presently available in our reserve, call obtain for | |
177c0ea7 JB |
444 | more space. |
445 | ||
abe9ff32 RS |
446 | Store the new location of each bloc in its new_data field. |
447 | Do not touch the contents of blocs or break_value. */ | |
dcfdbac7 | 448 | |
e429caa2 | 449 | static int |
971de7fb | 450 | relocate_blocs (bloc_ptr bloc, heap_ptr heap, POINTER address) |
e429caa2 KH |
451 | { |
452 | register bloc_ptr b = bloc; | |
ad3bb3d2 | 453 | |
49f82b3d | 454 | /* No need to ever call this if arena is frozen, bug somewhere! */ |
177c0ea7 | 455 | if (r_alloc_freeze_level) |
1088b922 | 456 | emacs_abort (); |
49f82b3d | 457 | |
e429caa2 KH |
458 | while (b) |
459 | { | |
abe9ff32 RS |
460 | /* If bloc B won't fit within HEAP, |
461 | move to the next heap and try again. */ | |
91a211b5 | 462 | while (heap && (char *) address + b->size > (char *) heap->end) |
e429caa2 KH |
463 | { |
464 | heap = heap->next; | |
465 | if (heap == NIL_HEAP) | |
466 | break; | |
467 | address = heap->bloc_start; | |
468 | } | |
dcfdbac7 | 469 | |
abe9ff32 RS |
470 | /* If BLOC won't fit in any heap, |
471 | get enough new space to hold BLOC and all following blocs. */ | |
e429caa2 KH |
472 | if (heap == NIL_HEAP) |
473 | { | |
474 | register bloc_ptr tb = b; | |
475 | register SIZE s = 0; | |
476 | ||
abe9ff32 | 477 | /* Add up the size of all the following blocs. */ |
e429caa2 KH |
478 | while (tb != NIL_BLOC) |
479 | { | |
177c0ea7 | 480 | if (tb->variable) |
49f82b3d RS |
481 | s += tb->size; |
482 | ||
e429caa2 KH |
483 | tb = tb->next; |
484 | } | |
485 | ||
abe9ff32 RS |
486 | /* Get that space. */ |
487 | address = obtain (address, s); | |
488 | if (address == 0) | |
e429caa2 KH |
489 | return 0; |
490 | ||
491 | heap = last_heap; | |
492 | } | |
493 | ||
abe9ff32 RS |
494 | /* Record the new address of this bloc |
495 | and update where the next bloc can start. */ | |
e429caa2 | 496 | b->new_data = address; |
177c0ea7 | 497 | if (b->variable) |
91a211b5 | 498 | address = (char *) address + b->size; |
e429caa2 KH |
499 | b = b->next; |
500 | } | |
501 | ||
502 | return 1; | |
503 | } | |
47f13333 RS |
504 | \f |
505 | /* Update the records of which heaps contain which blocs, starting | |
506 | with heap HEAP and bloc BLOC. */ | |
507 | ||
508 | static void | |
971de7fb | 509 | update_heap_bloc_correspondence (bloc_ptr bloc, heap_ptr heap) |
abe9ff32 RS |
510 | { |
511 | register bloc_ptr b; | |
512 | ||
47f13333 RS |
513 | /* Initialize HEAP's status to reflect blocs before BLOC. */ |
514 | if (bloc != NIL_BLOC && bloc->prev != NIL_BLOC && bloc->prev->heap == heap) | |
515 | { | |
516 | /* The previous bloc is in HEAP. */ | |
517 | heap->last_bloc = bloc->prev; | |
91a211b5 | 518 | heap->free = (char *) bloc->prev->data + bloc->prev->size; |
47f13333 RS |
519 | } |
520 | else | |
521 | { | |
522 | /* HEAP contains no blocs before BLOC. */ | |
523 | heap->first_bloc = NIL_BLOC; | |
524 | heap->last_bloc = NIL_BLOC; | |
525 | heap->free = heap->bloc_start; | |
526 | } | |
527 | ||
abe9ff32 RS |
528 | /* Advance through blocs one by one. */ |
529 | for (b = bloc; b != NIL_BLOC; b = b->next) | |
530 | { | |
47f13333 RS |
531 | /* Advance through heaps, marking them empty, |
532 | till we get to the one that B is in. */ | |
abe9ff32 RS |
533 | while (heap) |
534 | { | |
535 | if (heap->bloc_start <= b->data && b->data <= heap->end) | |
536 | break; | |
537 | heap = heap->next; | |
47f13333 RS |
538 | /* We know HEAP is not null now, |
539 | because there has to be space for bloc B. */ | |
540 | heap->first_bloc = NIL_BLOC; | |
541 | heap->last_bloc = NIL_BLOC; | |
abe9ff32 RS |
542 | heap->free = heap->bloc_start; |
543 | } | |
47f13333 RS |
544 | |
545 | /* Update HEAP's status for bloc B. */ | |
91a211b5 | 546 | heap->free = (char *) b->data + b->size; |
47f13333 RS |
547 | heap->last_bloc = b; |
548 | if (heap->first_bloc == NIL_BLOC) | |
549 | heap->first_bloc = b; | |
550 | ||
551 | /* Record that B is in HEAP. */ | |
552 | b->heap = heap; | |
abe9ff32 RS |
553 | } |
554 | ||
555 | /* If there are any remaining heaps and no blocs left, | |
47f13333 | 556 | mark those heaps as empty. */ |
abe9ff32 RS |
557 | heap = heap->next; |
558 | while (heap) | |
559 | { | |
47f13333 RS |
560 | heap->first_bloc = NIL_BLOC; |
561 | heap->last_bloc = NIL_BLOC; | |
abe9ff32 RS |
562 | heap->free = heap->bloc_start; |
563 | heap = heap->next; | |
564 | } | |
565 | } | |
47f13333 | 566 | \f |
abe9ff32 RS |
567 | /* Resize BLOC to SIZE bytes. This relocates the blocs |
568 | that come after BLOC in memory. */ | |
569 | ||
e429caa2 | 570 | static int |
971de7fb | 571 | resize_bloc (bloc_ptr bloc, SIZE size) |
dcfdbac7 | 572 | { |
e429caa2 KH |
573 | register bloc_ptr b; |
574 | heap_ptr heap; | |
575 | POINTER address; | |
576 | SIZE old_size; | |
577 | ||
49f82b3d | 578 | /* No need to ever call this if arena is frozen, bug somewhere! */ |
177c0ea7 | 579 | if (r_alloc_freeze_level) |
1088b922 | 580 | emacs_abort (); |
49f82b3d | 581 | |
e429caa2 KH |
582 | if (bloc == NIL_BLOC || size == bloc->size) |
583 | return 1; | |
584 | ||
585 | for (heap = first_heap; heap != NIL_HEAP; heap = heap->next) | |
586 | { | |
587 | if (heap->bloc_start <= bloc->data && bloc->data <= heap->end) | |
588 | break; | |
589 | } | |
590 | ||
591 | if (heap == NIL_HEAP) | |
1088b922 | 592 | emacs_abort (); |
e429caa2 KH |
593 | |
594 | old_size = bloc->size; | |
595 | bloc->size = size; | |
596 | ||
abe9ff32 | 597 | /* Note that bloc could be moved into the previous heap. */ |
91a211b5 GM |
598 | address = (bloc->prev ? (char *) bloc->prev->data + bloc->prev->size |
599 | : (char *) first_heap->bloc_start); | |
e429caa2 KH |
600 | while (heap) |
601 | { | |
602 | if (heap->bloc_start <= address && address <= heap->end) | |
603 | break; | |
604 | heap = heap->prev; | |
605 | } | |
606 | ||
607 | if (! relocate_blocs (bloc, heap, address)) | |
608 | { | |
609 | bloc->size = old_size; | |
610 | return 0; | |
611 | } | |
612 | ||
613 | if (size > old_size) | |
614 | { | |
615 | for (b = last_bloc; b != bloc; b = b->prev) | |
616 | { | |
49f82b3d RS |
617 | if (!b->variable) |
618 | { | |
619 | b->size = 0; | |
620 | b->data = b->new_data; | |
177c0ea7 JB |
621 | } |
622 | else | |
49f82b3d | 623 | { |
78cef877 EZ |
624 | if (b->new_data != b->data) |
625 | memmove (b->new_data, b->data, b->size); | |
49f82b3d RS |
626 | *b->variable = b->data = b->new_data; |
627 | } | |
628 | } | |
629 | if (!bloc->variable) | |
630 | { | |
631 | bloc->size = 0; | |
632 | bloc->data = bloc->new_data; | |
633 | } | |
634 | else | |
635 | { | |
78cef877 EZ |
636 | if (bloc->new_data != bloc->data) |
637 | memmove (bloc->new_data, bloc->data, old_size); | |
3ce2f8ac | 638 | memset ((char *) bloc->new_data + old_size, 0, size - old_size); |
49f82b3d | 639 | *bloc->variable = bloc->data = bloc->new_data; |
e429caa2 | 640 | } |
e429caa2 KH |
641 | } |
642 | else | |
dcfdbac7 | 643 | { |
ad3bb3d2 JB |
644 | for (b = bloc; b != NIL_BLOC; b = b->next) |
645 | { | |
49f82b3d RS |
646 | if (!b->variable) |
647 | { | |
648 | b->size = 0; | |
649 | b->data = b->new_data; | |
177c0ea7 JB |
650 | } |
651 | else | |
49f82b3d | 652 | { |
78cef877 EZ |
653 | if (b->new_data != b->data) |
654 | memmove (b->new_data, b->data, b->size); | |
49f82b3d RS |
655 | *b->variable = b->data = b->new_data; |
656 | } | |
ad3bb3d2 | 657 | } |
ad3bb3d2 | 658 | } |
dcfdbac7 | 659 | |
47f13333 | 660 | update_heap_bloc_correspondence (bloc, heap); |
abe9ff32 | 661 | |
91a211b5 GM |
662 | break_value = (last_bloc ? (char *) last_bloc->data + last_bloc->size |
663 | : (char *) first_heap->bloc_start); | |
e429caa2 KH |
664 | return 1; |
665 | } | |
47f13333 | 666 | \f |
abe9ff32 RS |
667 | /* Free BLOC from the chain of blocs, relocating any blocs above it. |
668 | This may return space to the system. */ | |
dcfdbac7 JB |
669 | |
670 | static void | |
971de7fb | 671 | free_bloc (bloc_ptr bloc) |
dcfdbac7 | 672 | { |
47f13333 | 673 | heap_ptr heap = bloc->heap; |
36c46f8e | 674 | heap_ptr h; |
47f13333 | 675 | |
49f82b3d RS |
676 | if (r_alloc_freeze_level) |
677 | { | |
678 | bloc->variable = (POINTER *) NIL; | |
679 | return; | |
680 | } | |
177c0ea7 | 681 | |
e429caa2 KH |
682 | resize_bloc (bloc, 0); |
683 | ||
dcfdbac7 JB |
684 | if (bloc == first_bloc && bloc == last_bloc) |
685 | { | |
686 | first_bloc = last_bloc = NIL_BLOC; | |
687 | } | |
688 | else if (bloc == last_bloc) | |
689 | { | |
690 | last_bloc = bloc->prev; | |
691 | last_bloc->next = NIL_BLOC; | |
692 | } | |
693 | else if (bloc == first_bloc) | |
694 | { | |
695 | first_bloc = bloc->next; | |
696 | first_bloc->prev = NIL_BLOC; | |
dcfdbac7 JB |
697 | } |
698 | else | |
699 | { | |
700 | bloc->next->prev = bloc->prev; | |
701 | bloc->prev->next = bloc->next; | |
dcfdbac7 JB |
702 | } |
703 | ||
36c46f8e EZ |
704 | /* Sometimes, 'heap' obtained from bloc->heap above is not really a |
705 | 'heap' structure. It can even be beyond the current break point, | |
706 | which will cause crashes when we dereference it below (see | |
707 | bug#12242). Evidently, the reason is bloc allocations done while | |
708 | use_relocatable_buffers was non-positive, because additional | |
709 | memory we get then is not recorded in the heaps we manage. If | |
710 | bloc->heap records such a "heap", we cannot (and don't need to) | |
711 | update its records. So we validate the 'heap' value by making | |
712 | sure it is one of the heaps we manage via the heaps linked list, | |
713 | and don't touch a 'heap' that isn't found there. This avoids | |
714 | accessing memory we know nothing about. */ | |
715 | for (h = first_heap; h != NIL_HEAP; h = h->next) | |
716 | if (heap == h) | |
717 | break; | |
718 | ||
719 | if (h) | |
47f13333 | 720 | { |
36c46f8e EZ |
721 | /* Update the records of which blocs are in HEAP. */ |
722 | if (heap->first_bloc == bloc) | |
723 | { | |
724 | if (bloc->next != 0 && bloc->next->heap == heap) | |
725 | heap->first_bloc = bloc->next; | |
726 | else | |
727 | heap->first_bloc = heap->last_bloc = NIL_BLOC; | |
728 | } | |
729 | if (heap->last_bloc == bloc) | |
730 | { | |
731 | if (bloc->prev != 0 && bloc->prev->heap == heap) | |
732 | heap->last_bloc = bloc->prev; | |
733 | else | |
734 | heap->first_bloc = heap->last_bloc = NIL_BLOC; | |
735 | } | |
47f13333 RS |
736 | } |
737 | ||
e429caa2 | 738 | relinquish (); |
dcfdbac7 JB |
739 | free (bloc); |
740 | } | |
741 | \f | |
956ace37 JB |
742 | /* Interface routines. */ |
743 | ||
98b7fe02 | 744 | /* Obtain SIZE bytes of storage from the free pool, or the system, as |
2c46d29f | 745 | necessary. If relocatable blocs are in use, this means relocating |
98b7fe02 JB |
746 | them. This function gets plugged into the GNU malloc's __morecore |
747 | hook. | |
748 | ||
7516b7d5 RS |
749 | We provide hysteresis, never relocating by less than extra_bytes. |
750 | ||
98b7fe02 JB |
751 | If we're out of memory, we should return zero, to imitate the other |
752 | __morecore hook values - in particular, __default_morecore in the | |
753 | GNU malloc package. */ | |
dcfdbac7 | 754 | |
3539f31f | 755 | static POINTER |
62aba0d4 | 756 | r_alloc_sbrk (ptrdiff_t size) |
dcfdbac7 | 757 | { |
e429caa2 KH |
758 | register bloc_ptr b; |
759 | POINTER address; | |
dcfdbac7 | 760 | |
44d3dec0 RS |
761 | if (! r_alloc_initialized) |
762 | r_alloc_init (); | |
763 | ||
e8a02204 | 764 | if (use_relocatable_buffers <= 0) |
bbc60227 | 765 | return (*real_morecore) (size); |
dcfdbac7 | 766 | |
e429caa2 KH |
767 | if (size == 0) |
768 | return virtual_break_value; | |
7516b7d5 | 769 | |
e429caa2 | 770 | if (size > 0) |
dcfdbac7 | 771 | { |
abe9ff32 RS |
772 | /* Allocate a page-aligned space. GNU malloc would reclaim an |
773 | extra space if we passed an unaligned one. But we could | |
8e6208c5 | 774 | not always find a space which is contiguous to the previous. */ |
e429caa2 KH |
775 | POINTER new_bloc_start; |
776 | heap_ptr h = first_heap; | |
abe9ff32 | 777 | SIZE get = ROUNDUP (size); |
7516b7d5 | 778 | |
abe9ff32 | 779 | address = (POINTER) ROUNDUP (virtual_break_value); |
e429caa2 | 780 | |
abe9ff32 RS |
781 | /* Search the list upward for a heap which is large enough. */ |
782 | while ((char *) h->end < (char *) MEM_ROUNDUP ((char *)address + get)) | |
e429caa2 KH |
783 | { |
784 | h = h->next; | |
785 | if (h == NIL_HEAP) | |
786 | break; | |
abe9ff32 | 787 | address = (POINTER) ROUNDUP (h->start); |
e429caa2 KH |
788 | } |
789 | ||
abe9ff32 | 790 | /* If not found, obtain more space. */ |
e429caa2 KH |
791 | if (h == NIL_HEAP) |
792 | { | |
793 | get += extra_bytes + page_size; | |
794 | ||
49f82b3d | 795 | if (! obtain (address, get)) |
e429caa2 | 796 | return 0; |
98b7fe02 | 797 | |
e429caa2 | 798 | if (first_heap == last_heap) |
abe9ff32 | 799 | address = (POINTER) ROUNDUP (virtual_break_value); |
e429caa2 | 800 | else |
abe9ff32 | 801 | address = (POINTER) ROUNDUP (last_heap->start); |
e429caa2 KH |
802 | h = last_heap; |
803 | } | |
804 | ||
abe9ff32 | 805 | new_bloc_start = (POINTER) MEM_ROUNDUP ((char *)address + get); |
e429caa2 KH |
806 | |
807 | if (first_heap->bloc_start < new_bloc_start) | |
808 | { | |
49f82b3d | 809 | /* This is no clean solution - no idea how to do it better. */ |
177c0ea7 | 810 | if (r_alloc_freeze_level) |
49f82b3d RS |
811 | return NIL; |
812 | ||
813 | /* There is a bug here: if the above obtain call succeeded, but the | |
814 | relocate_blocs call below does not succeed, we need to free | |
815 | the memory that we got with obtain. */ | |
816 | ||
abe9ff32 | 817 | /* Move all blocs upward. */ |
49f82b3d | 818 | if (! relocate_blocs (first_bloc, h, new_bloc_start)) |
e429caa2 KH |
819 | return 0; |
820 | ||
821 | /* Note that (POINTER)(h+1) <= new_bloc_start since | |
822 | get >= page_size, so the following does not destroy the heap | |
abe9ff32 | 823 | header. */ |
e429caa2 KH |
824 | for (b = last_bloc; b != NIL_BLOC; b = b->prev) |
825 | { | |
78cef877 EZ |
826 | if (b->new_data != b->data) |
827 | memmove (b->new_data, b->data, b->size); | |
e429caa2 KH |
828 | *b->variable = b->data = b->new_data; |
829 | } | |
830 | ||
831 | h->bloc_start = new_bloc_start; | |
abe9ff32 | 832 | |
47f13333 | 833 | update_heap_bloc_correspondence (first_bloc, h); |
e429caa2 | 834 | } |
e429caa2 KH |
835 | if (h != first_heap) |
836 | { | |
837 | /* Give up managing heaps below the one the new | |
abe9ff32 | 838 | virtual_break_value points to. */ |
e429caa2 KH |
839 | first_heap->prev = NIL_HEAP; |
840 | first_heap->next = h->next; | |
841 | first_heap->start = h->start; | |
842 | first_heap->end = h->end; | |
abe9ff32 | 843 | first_heap->free = h->free; |
47f13333 RS |
844 | first_heap->first_bloc = h->first_bloc; |
845 | first_heap->last_bloc = h->last_bloc; | |
e429caa2 KH |
846 | first_heap->bloc_start = h->bloc_start; |
847 | ||
848 | if (first_heap->next) | |
849 | first_heap->next->prev = first_heap; | |
850 | else | |
851 | last_heap = first_heap; | |
852 | } | |
853 | ||
72af86bd | 854 | memset (address, 0, size); |
dcfdbac7 | 855 | } |
e429caa2 | 856 | else /* size < 0 */ |
dcfdbac7 | 857 | { |
e429caa2 KH |
858 | SIZE excess = (char *)first_heap->bloc_start |
859 | - ((char *)virtual_break_value + size); | |
860 | ||
861 | address = virtual_break_value; | |
862 | ||
863 | if (r_alloc_freeze_level == 0 && excess > 2 * extra_bytes) | |
864 | { | |
865 | excess -= extra_bytes; | |
866 | first_heap->bloc_start | |
47f13333 | 867 | = (POINTER) MEM_ROUNDUP ((char *)first_heap->bloc_start - excess); |
e429caa2 | 868 | |
abe9ff32 | 869 | relocate_blocs (first_bloc, first_heap, first_heap->bloc_start); |
7516b7d5 | 870 | |
e429caa2 KH |
871 | for (b = first_bloc; b != NIL_BLOC; b = b->next) |
872 | { | |
78cef877 EZ |
873 | if (b->new_data != b->data) |
874 | memmove (b->new_data, b->data, b->size); | |
e429caa2 KH |
875 | *b->variable = b->data = b->new_data; |
876 | } | |
877 | } | |
878 | ||
879 | if ((char *)virtual_break_value + size < (char *)first_heap->start) | |
880 | { | |
881 | /* We found an additional space below the first heap */ | |
882 | first_heap->start = (POINTER) ((char *)virtual_break_value + size); | |
883 | } | |
dcfdbac7 JB |
884 | } |
885 | ||
e429caa2 | 886 | virtual_break_value = (POINTER) ((char *)address + size); |
47f13333 | 887 | break_value = (last_bloc |
91a211b5 GM |
888 | ? (char *) last_bloc->data + last_bloc->size |
889 | : (char *) first_heap->bloc_start); | |
e429caa2 | 890 | if (size < 0) |
abe9ff32 | 891 | relinquish (); |
7516b7d5 | 892 | |
e429caa2 | 893 | return address; |
dcfdbac7 JB |
894 | } |
895 | ||
0a58f946 | 896 | |
dcfdbac7 JB |
897 | /* Allocate a relocatable bloc of storage of size SIZE. A pointer to |
898 | the data is returned in *PTR. PTR is thus the address of some variable | |
98b7fe02 JB |
899 | which will use the data area. |
900 | ||
49f82b3d | 901 | The allocation of 0 bytes is valid. |
f96f2c5b JB |
902 | In case r_alloc_freeze_level is set, a best fit of unused blocs could be |
903 | done before allocating a new area. Not yet done. | |
49f82b3d | 904 | |
98b7fe02 JB |
905 | If we can't allocate the necessary memory, set *PTR to zero, and |
906 | return zero. */ | |
dcfdbac7 JB |
907 | |
908 | POINTER | |
971de7fb | 909 | r_alloc (POINTER *ptr, SIZE size) |
dcfdbac7 JB |
910 | { |
911 | register bloc_ptr new_bloc; | |
912 | ||
2c46d29f RS |
913 | if (! r_alloc_initialized) |
914 | r_alloc_init (); | |
915 | ||
abe9ff32 | 916 | new_bloc = get_bloc (MEM_ROUNDUP (size)); |
98b7fe02 JB |
917 | if (new_bloc) |
918 | { | |
919 | new_bloc->variable = ptr; | |
920 | *ptr = new_bloc->data; | |
921 | } | |
922 | else | |
923 | *ptr = 0; | |
dcfdbac7 JB |
924 | |
925 | return *ptr; | |
926 | } | |
927 | ||
2c46d29f RS |
928 | /* Free a bloc of relocatable storage whose data is pointed to by PTR. |
929 | Store 0 in *PTR to show there's no block allocated. */ | |
dcfdbac7 JB |
930 | |
931 | void | |
971de7fb | 932 | r_alloc_free (register POINTER *ptr) |
dcfdbac7 JB |
933 | { |
934 | register bloc_ptr dead_bloc; | |
935 | ||
44d3dec0 RS |
936 | if (! r_alloc_initialized) |
937 | r_alloc_init (); | |
938 | ||
dcfdbac7 JB |
939 | dead_bloc = find_bloc (ptr); |
940 | if (dead_bloc == NIL_BLOC) | |
1088b922 | 941 | emacs_abort (); /* Double free? PTR not originally used to allocate? */ |
dcfdbac7 JB |
942 | |
943 | free_bloc (dead_bloc); | |
2c46d29f | 944 | *ptr = 0; |
719b242f | 945 | |
d5179acc | 946 | #ifdef emacs |
719b242f | 947 | refill_memory_reserve (); |
d5179acc | 948 | #endif |
dcfdbac7 JB |
949 | } |
950 | ||
16a5c729 | 951 | /* Given a pointer at address PTR to relocatable data, resize it to SIZE. |
98b7fe02 JB |
952 | Do this by shifting all blocks above this one up in memory, unless |
953 | SIZE is less than or equal to the current bloc size, in which case | |
954 | do nothing. | |
dcfdbac7 | 955 | |
f96f2c5b | 956 | In case r_alloc_freeze_level is set, a new bloc is allocated, and the |
8e6208c5 | 957 | memory copied to it. Not very efficient. We could traverse the |
49f82b3d RS |
958 | bloc_list for a best fit of free blocs first. |
959 | ||
98b7fe02 JB |
960 | Change *PTR to reflect the new bloc, and return this value. |
961 | ||
962 | If more memory cannot be allocated, then leave *PTR unchanged, and | |
963 | return zero. */ | |
dcfdbac7 JB |
964 | |
965 | POINTER | |
971de7fb | 966 | r_re_alloc (POINTER *ptr, SIZE size) |
dcfdbac7 | 967 | { |
16a5c729 | 968 | register bloc_ptr bloc; |
dcfdbac7 | 969 | |
44d3dec0 RS |
970 | if (! r_alloc_initialized) |
971 | r_alloc_init (); | |
972 | ||
49f82b3d RS |
973 | if (!*ptr) |
974 | return r_alloc (ptr, size); | |
177c0ea7 | 975 | if (!size) |
49f82b3d RS |
976 | { |
977 | r_alloc_free (ptr); | |
978 | return r_alloc (ptr, 0); | |
979 | } | |
980 | ||
16a5c729 JB |
981 | bloc = find_bloc (ptr); |
982 | if (bloc == NIL_BLOC) | |
1088b922 | 983 | emacs_abort (); /* Already freed? PTR not originally used to allocate? */ |
dcfdbac7 | 984 | |
177c0ea7 | 985 | if (size < bloc->size) |
49f82b3d RS |
986 | { |
987 | /* Wouldn't it be useful to actually resize the bloc here? */ | |
988 | /* I think so too, but not if it's too expensive... */ | |
177c0ea7 JB |
989 | if ((bloc->size - MEM_ROUNDUP (size) >= page_size) |
990 | && r_alloc_freeze_level == 0) | |
49f82b3d RS |
991 | { |
992 | resize_bloc (bloc, MEM_ROUNDUP (size)); | |
993 | /* Never mind if this fails, just do nothing... */ | |
994 | /* It *should* be infallible! */ | |
995 | } | |
996 | } | |
997 | else if (size > bloc->size) | |
998 | { | |
999 | if (r_alloc_freeze_level) | |
1000 | { | |
1001 | bloc_ptr new_bloc; | |
1002 | new_bloc = get_bloc (MEM_ROUNDUP (size)); | |
1003 | if (new_bloc) | |
1004 | { | |
1005 | new_bloc->variable = ptr; | |
1006 | *ptr = new_bloc->data; | |
1007 | bloc->variable = (POINTER *) NIL; | |
1008 | } | |
1009 | else | |
1010 | return NIL; | |
1011 | } | |
177c0ea7 | 1012 | else |
49f82b3d RS |
1013 | { |
1014 | if (! resize_bloc (bloc, MEM_ROUNDUP (size))) | |
1015 | return NIL; | |
1016 | } | |
1017 | } | |
dcfdbac7 JB |
1018 | return *ptr; |
1019 | } | |
81bd58e8 | 1020 | |
dec41418 RS |
1021 | |
1022 | #if defined (emacs) && defined (DOUG_LEA_MALLOC) | |
1023 | ||
1024 | /* Reinitialize the morecore hook variables after restarting a dumped | |
1025 | Emacs. This is needed when using Doug Lea's malloc from GNU libc. */ | |
1026 | void | |
971de7fb | 1027 | r_alloc_reinit (void) |
dec41418 RS |
1028 | { |
1029 | /* Only do this if the hook has been reset, so that we don't get an | |
1030 | infinite loop, in case Emacs was linked statically. */ | |
1031 | if (__morecore != r_alloc_sbrk) | |
1032 | { | |
1033 | real_morecore = __morecore; | |
1034 | __morecore = r_alloc_sbrk; | |
1035 | } | |
1036 | } | |
0a58f946 GM |
1037 | |
1038 | #endif /* emacs && DOUG_LEA_MALLOC */ | |
dec41418 | 1039 | |
e429caa2 | 1040 | #ifdef DEBUG |
0a58f946 | 1041 | |
e429caa2 KH |
1042 | #include <assert.h> |
1043 | ||
44d3dec0 | 1044 | void |
268c2c36 | 1045 | r_alloc_check (void) |
e429caa2 | 1046 | { |
6d16dd06 RS |
1047 | int found = 0; |
1048 | heap_ptr h, ph = 0; | |
1049 | bloc_ptr b, pb = 0; | |
1050 | ||
1051 | if (!r_alloc_initialized) | |
1052 | return; | |
1053 | ||
1054 | assert (first_heap); | |
1055 | assert (last_heap->end <= (POINTER) sbrk (0)); | |
1056 | assert ((POINTER) first_heap < first_heap->start); | |
1057 | assert (first_heap->start <= virtual_break_value); | |
1058 | assert (virtual_break_value <= first_heap->end); | |
1059 | ||
1060 | for (h = first_heap; h; h = h->next) | |
1061 | { | |
1062 | assert (h->prev == ph); | |
1063 | assert ((POINTER) ROUNDUP (h->end) == h->end); | |
40f3f04b RS |
1064 | #if 0 /* ??? The code in ralloc.c does not really try to ensure |
1065 | the heap start has any sort of alignment. | |
1066 | Perhaps it should. */ | |
6d16dd06 | 1067 | assert ((POINTER) MEM_ROUNDUP (h->start) == h->start); |
40f3f04b | 1068 | #endif |
6d16dd06 RS |
1069 | assert ((POINTER) MEM_ROUNDUP (h->bloc_start) == h->bloc_start); |
1070 | assert (h->start <= h->bloc_start && h->bloc_start <= h->end); | |
1071 | ||
1072 | if (ph) | |
1073 | { | |
1074 | assert (ph->end < h->start); | |
1075 | assert (h->start <= (POINTER)h && (POINTER)(h+1) <= h->bloc_start); | |
1076 | } | |
1077 | ||
1078 | if (h->bloc_start <= break_value && break_value <= h->end) | |
1079 | found = 1; | |
1080 | ||
1081 | ph = h; | |
1082 | } | |
1083 | ||
1084 | assert (found); | |
1085 | assert (last_heap == ph); | |
1086 | ||
1087 | for (b = first_bloc; b; b = b->next) | |
1088 | { | |
1089 | assert (b->prev == pb); | |
1090 | assert ((POINTER) MEM_ROUNDUP (b->data) == b->data); | |
1091 | assert ((SIZE) MEM_ROUNDUP (b->size) == b->size); | |
1092 | ||
1093 | ph = 0; | |
1094 | for (h = first_heap; h; h = h->next) | |
1095 | { | |
1096 | if (h->bloc_start <= b->data && b->data + b->size <= h->end) | |
1097 | break; | |
1098 | ph = h; | |
1099 | } | |
1100 | ||
1101 | assert (h); | |
1102 | ||
1103 | if (pb && pb->data + pb->size != b->data) | |
1104 | { | |
1105 | assert (ph && b->data == h->bloc_start); | |
1106 | while (ph) | |
1107 | { | |
1108 | if (ph->bloc_start <= pb->data | |
1109 | && pb->data + pb->size <= ph->end) | |
1110 | { | |
1111 | assert (pb->data + pb->size + b->size > ph->end); | |
1112 | break; | |
1113 | } | |
1114 | else | |
1115 | { | |
1116 | assert (ph->bloc_start + b->size > ph->end); | |
1117 | } | |
1118 | ph = ph->prev; | |
1119 | } | |
1120 | } | |
1121 | pb = b; | |
1122 | } | |
1123 | ||
1124 | assert (last_bloc == pb); | |
1125 | ||
1126 | if (last_bloc) | |
1127 | assert (last_bloc->data + last_bloc->size == break_value); | |
1128 | else | |
1129 | assert (first_heap->bloc_start == break_value); | |
e429caa2 | 1130 | } |
0a58f946 | 1131 | |
e429caa2 | 1132 | #endif /* DEBUG */ |
0a58f946 | 1133 | |
baae5c2d JR |
1134 | /* Update the internal record of which variable points to some data to NEW. |
1135 | Used by buffer-swap-text in Emacs to restore consistency after it | |
1136 | swaps the buffer text between two buffer objects. The OLD pointer | |
1137 | is checked to ensure that memory corruption does not occur due to | |
1138 | misuse. */ | |
1139 | void | |
971de7fb | 1140 | r_alloc_reset_variable (POINTER *old, POINTER *new) |
baae5c2d JR |
1141 | { |
1142 | bloc_ptr bloc = first_bloc; | |
1143 | ||
1144 | /* Find the bloc that corresponds to the data pointed to by pointer. | |
1145 | find_bloc cannot be used, as it has internal consistency checks | |
0d26e0b6 | 1146 | which fail when the variable needs resetting. */ |
baae5c2d JR |
1147 | while (bloc != NIL_BLOC) |
1148 | { | |
1149 | if (bloc->data == *new) | |
1150 | break; | |
1151 | ||
1152 | bloc = bloc->next; | |
1153 | } | |
1154 | ||
1155 | if (bloc == NIL_BLOC || bloc->variable != old) | |
1088b922 | 1156 | emacs_abort (); /* Already freed? OLD not originally used to allocate? */ |
baae5c2d JR |
1157 | |
1158 | /* Update variable to point to the new location. */ | |
1159 | bloc->variable = new; | |
1160 | } | |
0a58f946 | 1161 | |
52c55cc7 EZ |
1162 | void |
1163 | r_alloc_inhibit_buffer_relocation (int inhibit) | |
1164 | { | |
e8a02204 EZ |
1165 | if (use_relocatable_buffers > 1) |
1166 | use_relocatable_buffers = 1; | |
291d430f | 1167 | if (inhibit) |
291d430f | 1168 | use_relocatable_buffers--; |
e8a02204 EZ |
1169 | else if (use_relocatable_buffers < 1) |
1170 | use_relocatable_buffers++; | |
52c55cc7 EZ |
1171 | } |
1172 | ||
0a58f946 GM |
1173 | \f |
1174 | /*********************************************************************** | |
1175 | Initialization | |
1176 | ***********************************************************************/ | |
1177 | ||
0a58f946 GM |
1178 | /* Initialize various things for memory allocation. */ |
1179 | ||
1180 | static void | |
971de7fb | 1181 | r_alloc_init (void) |
0a58f946 GM |
1182 | { |
1183 | if (r_alloc_initialized) | |
1184 | return; | |
0a58f946 | 1185 | r_alloc_initialized = 1; |
177c0ea7 | 1186 | |
a2c23c92 DL |
1187 | page_size = PAGE; |
1188 | #ifndef SYSTEM_MALLOC | |
0a58f946 GM |
1189 | real_morecore = __morecore; |
1190 | __morecore = r_alloc_sbrk; | |
1191 | ||
1192 | first_heap = last_heap = &heap_base; | |
1193 | first_heap->next = first_heap->prev = NIL_HEAP; | |
1194 | first_heap->start = first_heap->bloc_start | |
1195 | = virtual_break_value = break_value = (*real_morecore) (0); | |
1196 | if (break_value == NIL) | |
1088b922 | 1197 | emacs_abort (); |
0a58f946 | 1198 | |
0a58f946 | 1199 | extra_bytes = ROUNDUP (50000); |
a2c23c92 | 1200 | #endif |
0a58f946 GM |
1201 | |
1202 | #ifdef DOUG_LEA_MALLOC | |
4d7e6e51 | 1203 | block_input (); |
1673df2e | 1204 | mallopt (M_TOP_PAD, 64 * 4096); |
4d7e6e51 | 1205 | unblock_input (); |
0a58f946 | 1206 | #else |
a2c23c92 | 1207 | #ifndef SYSTEM_MALLOC |
45ba16c7 EZ |
1208 | /* Give GNU malloc's morecore some hysteresis so that we move all |
1209 | the relocatable blocks much less often. The number used to be | |
1210 | 64, but alloc.c would override that with 32 in code that was | |
1211 | removed when SYNC_INPUT became the only input handling mode. | |
9b318728 | 1212 | That code was conditioned on !DOUG_LEA_MALLOC, so the call to |
45ba16c7 EZ |
1213 | mallopt above is left unchanged. (Actually, I think there's no |
1214 | system nowadays that uses DOUG_LEA_MALLOC and also uses | |
1215 | REL_ALLOC.) */ | |
1216 | __malloc_extra_blocks = 32; | |
0a58f946 | 1217 | #endif |
a2c23c92 | 1218 | #endif |
0a58f946 | 1219 | |
5ad25b24 | 1220 | #ifndef SYSTEM_MALLOC |
0a58f946 GM |
1221 | first_heap->end = (POINTER) ROUNDUP (first_heap->start); |
1222 | ||
1223 | /* The extra call to real_morecore guarantees that the end of the | |
1224 | address space is a multiple of page_size, even if page_size is | |
1225 | not really the page size of the system running the binary in | |
1226 | which page_size is stored. This allows a binary to be built on a | |
1227 | system with one page size and run on a system with a smaller page | |
1228 | size. */ | |
91a211b5 | 1229 | (*real_morecore) ((char *) first_heap->end - (char *) first_heap->start); |
0a58f946 GM |
1230 | |
1231 | /* Clear the rest of the last page; this memory is in our address space | |
1232 | even though it is after the sbrk value. */ | |
1233 | /* Doubly true, with the additional call that explicitly adds the | |
1234 | rest of that page to the address space. */ | |
72af86bd AS |
1235 | memset (first_heap->start, 0, |
1236 | (char *) first_heap->end - (char *) first_heap->start); | |
0a58f946 | 1237 | virtual_break_value = break_value = first_heap->bloc_start = first_heap->end; |
a2c23c92 | 1238 | #endif |
177c0ea7 | 1239 | |
0a58f946 GM |
1240 | use_relocatable_buffers = 1; |
1241 | } |