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 | |
2c46d29f RS |
55 | /* A flag to indicate whether we have initialized ralloc yet. For |
56 | Emacs's sake, please do not make this local to malloc_init; on some | |
57 | machines, the dumping procedure makes all static variables | |
58 | read-only. On these machines, the word static is #defined to be | |
59 | the empty string, meaning that r_alloc_initialized becomes an | |
0a58f946 GM |
60 | automatic variable, and loses its value each time Emacs is started |
61 | up. */ | |
62 | ||
2c46d29f RS |
63 | static int r_alloc_initialized = 0; |
64 | ||
971de7fb | 65 | static void r_alloc_init (void); |
0a58f946 | 66 | |
dcfdbac7 | 67 | \f |
956ace37 JB |
68 | /* Declarations for working with the malloc, ralloc, and system breaks. */ |
69 | ||
abe9ff32 | 70 | /* Function to set the real break value. */ |
fcee5028 | 71 | void *(*real_morecore) (ptrdiff_t); |
dcfdbac7 | 72 | |
abe9ff32 | 73 | /* The break value, as seen by malloc. */ |
fcee5028 | 74 | static void *virtual_break_value; |
dcfdbac7 | 75 | |
abe9ff32 RS |
76 | /* The address of the end of the last data in use by ralloc, |
77 | including relocatable blocs as well as malloc data. */ | |
fcee5028 | 78 | static void *break_value; |
dcfdbac7 | 79 | |
7516b7d5 RS |
80 | /* This is the size of a page. We round memory requests to this boundary. */ |
81 | static int page_size; | |
82 | ||
177c0ea7 | 83 | /* Whenever we get memory from the system, get this many extra bytes. This |
ad3bb3d2 | 84 | must be a multiple of page_size. */ |
7516b7d5 RS |
85 | static int extra_bytes; |
86 | ||
dcfdbac7 | 87 | /* Macros for rounding. Note that rounding to any value is possible |
abe9ff32 | 88 | by changing the definition of PAGE. */ |
dcfdbac7 | 89 | #define PAGE (getpagesize ()) |
62aba0d4 | 90 | #define ROUNDUP(size) (((size_t) (size) + page_size - 1) \ |
fcee5028 | 91 | & ~((size_t) (page_size - 1))) |
e429caa2 | 92 | |
5e617bc2 | 93 | #define MEM_ALIGN sizeof (double) |
fcee5028 | 94 | #define MEM_ROUNDUP(addr) (((size_t) (addr) + MEM_ALIGN - 1) \ |
2d7d1608 | 95 | & ~(MEM_ALIGN - 1)) |
0a58f946 | 96 | |
aeac019e GM |
97 | /* The hook `malloc' uses for the function which gets more space |
98 | from the system. */ | |
99 | ||
100 | #ifndef SYSTEM_MALLOC | |
fcee5028 | 101 | extern void *(*__morecore) (ptrdiff_t); |
aeac019e GM |
102 | #endif |
103 | ||
104 | ||
e429caa2 | 105 | \f |
0a58f946 GM |
106 | /*********************************************************************** |
107 | Implementation using sbrk | |
108 | ***********************************************************************/ | |
109 | ||
abe9ff32 RS |
110 | /* Data structures of heaps and blocs. */ |
111 | ||
112 | /* The relocatable objects, or blocs, and the malloc data | |
113 | both reside within one or more heaps. | |
114 | Each heap contains malloc data, running from `start' to `bloc_start', | |
115 | and relocatable objects, running from `bloc_start' to `free'. | |
116 | ||
117 | Relocatable objects may relocate within the same heap | |
118 | or may move into another heap; the heaps themselves may grow | |
119 | but they never move. | |
120 | ||
121 | We try to make just one heap and make it larger as necessary. | |
8e6208c5 | 122 | But sometimes we can't do that, because we can't get contiguous |
abe9ff32 | 123 | space to add onto the heap. When that happens, we start a new heap. */ |
177c0ea7 | 124 | |
e429caa2 KH |
125 | typedef struct heap |
126 | { | |
127 | struct heap *next; | |
128 | struct heap *prev; | |
abe9ff32 | 129 | /* Start of memory range of this heap. */ |
fcee5028 | 130 | void *start; |
abe9ff32 | 131 | /* End of memory range of this heap. */ |
fcee5028 | 132 | void *end; |
abe9ff32 | 133 | /* Start of relocatable data in this heap. */ |
fcee5028 | 134 | void *bloc_start; |
abe9ff32 | 135 | /* Start of unused space in this heap. */ |
fcee5028 | 136 | void *free; |
47f13333 RS |
137 | /* First bloc in this heap. */ |
138 | struct bp *first_bloc; | |
139 | /* Last bloc in this heap. */ | |
140 | struct bp *last_bloc; | |
e429caa2 KH |
141 | } *heap_ptr; |
142 | ||
143 | #define NIL_HEAP ((heap_ptr) 0) | |
e429caa2 | 144 | |
abe9ff32 RS |
145 | /* This is the first heap object. |
146 | If we need additional heap objects, each one resides at the beginning of | |
147 | the space it covers. */ | |
148 | static struct heap heap_base; | |
149 | ||
150 | /* Head and tail of the list of heaps. */ | |
e429caa2 KH |
151 | static heap_ptr first_heap, last_heap; |
152 | ||
153 | /* These structures are allocated in the malloc arena. | |
154 | The linked list is kept in order of increasing '.data' members. | |
155 | The data blocks abut each other; if b->next is non-nil, then | |
177c0ea7 | 156 | b->data + b->size == b->next->data. |
49f82b3d | 157 | |
fcee5028 | 158 | An element with variable==NULL denotes a freed block, which has not yet |
f96f2c5b JB |
159 | been collected. They may only appear while r_alloc_freeze_level > 0, |
160 | and will be freed when the arena is thawed. Currently, these blocs are | |
161 | not reusable, while the arena is frozen. Very inefficient. */ | |
49f82b3d | 162 | |
e429caa2 KH |
163 | typedef struct bp |
164 | { | |
165 | struct bp *next; | |
166 | struct bp *prev; | |
fcee5028 PE |
167 | void **variable; |
168 | void *data; | |
169 | size_t size; | |
170 | void *new_data; /* temporarily used for relocation */ | |
49f82b3d | 171 | struct heap *heap; /* Heap this bloc is in. */ |
e429caa2 KH |
172 | } *bloc_ptr; |
173 | ||
174 | #define NIL_BLOC ((bloc_ptr) 0) | |
175 | #define BLOC_PTR_SIZE (sizeof (struct bp)) | |
176 | ||
abe9ff32 | 177 | /* Head and tail of the list of relocatable blocs. */ |
e429caa2 KH |
178 | static bloc_ptr first_bloc, last_bloc; |
179 | ||
49f82b3d RS |
180 | static int use_relocatable_buffers; |
181 | ||
182 | /* If >0, no relocation whatsoever takes place. */ | |
183 | static int r_alloc_freeze_level; | |
184 | ||
dcfdbac7 | 185 | \f |
956ace37 JB |
186 | /* Functions to get and return memory from the system. */ |
187 | ||
abe9ff32 RS |
188 | /* Find the heap that ADDRESS falls within. */ |
189 | ||
190 | static heap_ptr | |
fcee5028 | 191 | find_heap (void *address) |
abe9ff32 RS |
192 | { |
193 | heap_ptr heap; | |
194 | ||
195 | for (heap = last_heap; heap; heap = heap->prev) | |
196 | { | |
197 | if (heap->start <= address && address <= heap->end) | |
198 | return heap; | |
199 | } | |
200 | ||
201 | return NIL_HEAP; | |
202 | } | |
203 | ||
204 | /* Find SIZE bytes of space in a heap. | |
205 | Try to get them at ADDRESS (which must fall within some heap's range) | |
206 | if we can get that many within one heap. | |
207 | ||
e429caa2 | 208 | If enough space is not presently available in our reserve, this means |
8e6208c5 KH |
209 | getting more page-aligned space from the system. If the returned space |
210 | is not contiguous to the last heap, allocate a new heap, and append it | |
0d26e0b6 | 211 | to the heap list. |
abe9ff32 | 212 | |
0d26e0b6 JB |
213 | obtain does not try to keep track of whether space is in use or not |
214 | in use. It just returns the address of SIZE bytes that fall within a | |
215 | single heap. If you call obtain twice in a row with the same arguments, | |
216 | you typically get the same value. It's the caller's responsibility to | |
217 | keep track of what space is in use. | |
dcfdbac7 | 218 | |
e429caa2 KH |
219 | Return the address of the space if all went well, or zero if we couldn't |
220 | allocate the memory. */ | |
abe9ff32 | 221 | |
fcee5028 PE |
222 | static void * |
223 | obtain (void *address, size_t size) | |
dcfdbac7 | 224 | { |
e429caa2 | 225 | heap_ptr heap; |
fcee5028 | 226 | size_t already_available; |
dcfdbac7 | 227 | |
abe9ff32 | 228 | /* Find the heap that ADDRESS falls within. */ |
e429caa2 | 229 | for (heap = last_heap; heap; heap = heap->prev) |
dcfdbac7 | 230 | { |
e429caa2 KH |
231 | if (heap->start <= address && address <= heap->end) |
232 | break; | |
233 | } | |
dcfdbac7 | 234 | |
e429caa2 | 235 | if (! heap) |
1088b922 | 236 | emacs_abort (); |
dcfdbac7 | 237 | |
abe9ff32 RS |
238 | /* If we can't fit SIZE bytes in that heap, |
239 | try successive later heaps. */ | |
91a211b5 | 240 | while (heap && (char *) address + size > (char *) heap->end) |
e429caa2 KH |
241 | { |
242 | heap = heap->next; | |
243 | if (heap == NIL_HEAP) | |
244 | break; | |
245 | address = heap->bloc_start; | |
dcfdbac7 JB |
246 | } |
247 | ||
abe9ff32 RS |
248 | /* If we can't fit them within any existing heap, |
249 | get more space. */ | |
e429caa2 KH |
250 | if (heap == NIL_HEAP) |
251 | { | |
fcee5028 PE |
252 | void *new = real_morecore (0); |
253 | size_t get; | |
98b7fe02 | 254 | |
fcee5028 | 255 | already_available = (char *) last_heap->end - (char *) address; |
dcfdbac7 | 256 | |
e429caa2 KH |
257 | if (new != last_heap->end) |
258 | { | |
abe9ff32 RS |
259 | /* Someone else called sbrk. Make a new heap. */ |
260 | ||
261 | heap_ptr new_heap = (heap_ptr) MEM_ROUNDUP (new); | |
fcee5028 | 262 | void *bloc_start = (void *) MEM_ROUNDUP ((void *) (new_heap + 1)); |
e429caa2 | 263 | |
fcee5028 | 264 | if (real_morecore ((char *) bloc_start - (char *) new) != new) |
e429caa2 KH |
265 | return 0; |
266 | ||
267 | new_heap->start = new; | |
268 | new_heap->end = bloc_start; | |
269 | new_heap->bloc_start = bloc_start; | |
abe9ff32 | 270 | new_heap->free = bloc_start; |
e429caa2 KH |
271 | new_heap->next = NIL_HEAP; |
272 | new_heap->prev = last_heap; | |
47f13333 RS |
273 | new_heap->first_bloc = NIL_BLOC; |
274 | new_heap->last_bloc = NIL_BLOC; | |
e429caa2 KH |
275 | last_heap->next = new_heap; |
276 | last_heap = new_heap; | |
277 | ||
278 | address = bloc_start; | |
279 | already_available = 0; | |
280 | } | |
dcfdbac7 | 281 | |
abe9ff32 RS |
282 | /* Add space to the last heap (which we may have just created). |
283 | Get some extra, so we can come here less often. */ | |
284 | ||
e429caa2 | 285 | get = size + extra_bytes - already_available; |
fcee5028 | 286 | get = (char *) ROUNDUP ((char *) last_heap->end + get) |
e429caa2 | 287 | - (char *) last_heap->end; |
dcfdbac7 | 288 | |
fcee5028 | 289 | if (real_morecore (get) != last_heap->end) |
e429caa2 KH |
290 | return 0; |
291 | ||
91a211b5 | 292 | last_heap->end = (char *) last_heap->end + get; |
e429caa2 KH |
293 | } |
294 | ||
295 | return address; | |
296 | } | |
dcfdbac7 | 297 | |
abe9ff32 RS |
298 | /* Return unused heap space to the system |
299 | if there is a lot of unused space now. | |
300 | This can make the last heap smaller; | |
301 | it can also eliminate the last heap entirely. */ | |
302 | ||
dcfdbac7 | 303 | static void |
971de7fb | 304 | relinquish (void) |
dcfdbac7 | 305 | { |
e429caa2 | 306 | register heap_ptr h; |
62aba0d4 | 307 | ptrdiff_t excess = 0; |
e429caa2 | 308 | |
abe9ff32 RS |
309 | /* Add the amount of space beyond break_value |
310 | in all heaps which have extend beyond break_value at all. */ | |
311 | ||
e429caa2 KH |
312 | for (h = last_heap; h && break_value < h->end; h = h->prev) |
313 | { | |
314 | excess += (char *) h->end - (char *) ((break_value < h->bloc_start) | |
315 | ? h->bloc_start : break_value); | |
316 | } | |
317 | ||
fcee5028 | 318 | if (excess > extra_bytes * 2 && real_morecore (0) == last_heap->end) |
dcfdbac7 | 319 | { |
7516b7d5 RS |
320 | /* Keep extra_bytes worth of empty space. |
321 | And don't free anything unless we can free at least extra_bytes. */ | |
e429caa2 | 322 | excess -= extra_bytes; |
dcfdbac7 | 323 | |
fcee5028 | 324 | if ((char *) last_heap->end - (char *) last_heap->bloc_start <= excess) |
e429caa2 | 325 | { |
508f51f5 EZ |
326 | heap_ptr lh_prev; |
327 | ||
98daa893 EZ |
328 | /* This heap should have no blocs in it. If it does, we |
329 | cannot return it to the system. */ | |
47f13333 RS |
330 | if (last_heap->first_bloc != NIL_BLOC |
331 | || last_heap->last_bloc != NIL_BLOC) | |
98daa893 | 332 | return; |
47f13333 | 333 | |
abe9ff32 | 334 | /* Return the last heap, with its header, to the system. */ |
fcee5028 | 335 | excess = (char *) last_heap->end - (char *) last_heap->start; |
508f51f5 EZ |
336 | lh_prev = last_heap->prev; |
337 | /* If the system doesn't want that much memory back, leave | |
338 | last_heap unaltered to reflect that. This can occur if | |
339 | break_value is still within the original data segment. */ | |
fcee5028 | 340 | if (real_morecore (- excess) != 0) |
508f51f5 EZ |
341 | { |
342 | last_heap = lh_prev; | |
343 | last_heap->next = NIL_HEAP; | |
344 | } | |
e429caa2 KH |
345 | } |
346 | else | |
347 | { | |
fcee5028 PE |
348 | excess = ((char *) last_heap->end |
349 | - (char *) ROUNDUP ((char *) last_heap->end - excess)); | |
508f51f5 EZ |
350 | /* If the system doesn't want that much memory back, leave |
351 | the end of the last heap unchanged to reflect that. This | |
352 | can occur if break_value is still within the original | |
353 | data segment. */ | |
fcee5028 | 354 | if (real_morecore (- excess) != 0) |
508f51f5 | 355 | last_heap->end = (char *) last_heap->end - excess; |
21532667 | 356 | } |
e429caa2 | 357 | } |
dcfdbac7 JB |
358 | } |
359 | \f | |
956ace37 JB |
360 | /* The meat - allocating, freeing, and relocating blocs. */ |
361 | ||
956ace37 | 362 | /* Find the bloc referenced by the address in PTR. Returns a pointer |
abe9ff32 | 363 | to that block. */ |
dcfdbac7 JB |
364 | |
365 | static bloc_ptr | |
fcee5028 | 366 | find_bloc (void **ptr) |
dcfdbac7 | 367 | { |
fcee5028 | 368 | bloc_ptr p = first_bloc; |
dcfdbac7 JB |
369 | |
370 | while (p != NIL_BLOC) | |
371 | { | |
747d9d14 | 372 | /* Consistency check. Don't return inconsistent blocs. |
0d26e0b6 | 373 | Don't abort here, as callers might be expecting this, but |
747d9d14 JR |
374 | callers that always expect a bloc to be returned should abort |
375 | if one isn't to avoid a memory corruption bug that is | |
376 | difficult to track down. */ | |
dcfdbac7 JB |
377 | if (p->variable == ptr && p->data == *ptr) |
378 | return p; | |
379 | ||
380 | p = p->next; | |
381 | } | |
382 | ||
383 | return p; | |
384 | } | |
385 | ||
386 | /* Allocate a bloc of SIZE bytes and append it to the chain of blocs. | |
98b7fe02 JB |
387 | Returns a pointer to the new bloc, or zero if we couldn't allocate |
388 | memory for the new block. */ | |
dcfdbac7 JB |
389 | |
390 | static bloc_ptr | |
fcee5028 | 391 | get_bloc (size_t size) |
dcfdbac7 | 392 | { |
fcee5028 PE |
393 | bloc_ptr new_bloc; |
394 | heap_ptr heap; | |
98b7fe02 | 395 | |
38182d90 | 396 | if (! (new_bloc = malloc (BLOC_PTR_SIZE)) |
e429caa2 | 397 | || ! (new_bloc->data = obtain (break_value, size))) |
98b7fe02 | 398 | { |
c2cd06e6 | 399 | free (new_bloc); |
98b7fe02 JB |
400 | |
401 | return 0; | |
402 | } | |
dcfdbac7 | 403 | |
91a211b5 | 404 | break_value = (char *) new_bloc->data + size; |
e429caa2 | 405 | |
dcfdbac7 JB |
406 | new_bloc->size = size; |
407 | new_bloc->next = NIL_BLOC; | |
fcee5028 | 408 | new_bloc->variable = NULL; |
e429caa2 | 409 | new_bloc->new_data = 0; |
dcfdbac7 | 410 | |
abe9ff32 RS |
411 | /* Record in the heap that this space is in use. */ |
412 | heap = find_heap (new_bloc->data); | |
413 | heap->free = break_value; | |
414 | ||
47f13333 RS |
415 | /* Maintain the correspondence between heaps and blocs. */ |
416 | new_bloc->heap = heap; | |
417 | heap->last_bloc = new_bloc; | |
418 | if (heap->first_bloc == NIL_BLOC) | |
419 | heap->first_bloc = new_bloc; | |
420 | ||
abe9ff32 | 421 | /* Put this bloc on the doubly-linked list of blocs. */ |
dcfdbac7 JB |
422 | if (first_bloc) |
423 | { | |
424 | new_bloc->prev = last_bloc; | |
425 | last_bloc->next = new_bloc; | |
426 | last_bloc = new_bloc; | |
427 | } | |
428 | else | |
429 | { | |
430 | first_bloc = last_bloc = new_bloc; | |
431 | new_bloc->prev = NIL_BLOC; | |
432 | } | |
433 | ||
434 | return new_bloc; | |
435 | } | |
47f13333 | 436 | \f |
abe9ff32 RS |
437 | /* Calculate new locations of blocs in the list beginning with BLOC, |
438 | relocating it to start at ADDRESS, in heap HEAP. If enough space is | |
439 | not presently available in our reserve, call obtain for | |
177c0ea7 JB |
440 | more space. |
441 | ||
abe9ff32 RS |
442 | Store the new location of each bloc in its new_data field. |
443 | Do not touch the contents of blocs or break_value. */ | |
dcfdbac7 | 444 | |
e429caa2 | 445 | static int |
fcee5028 | 446 | relocate_blocs (bloc_ptr bloc, heap_ptr heap, void *address) |
e429caa2 | 447 | { |
fcee5028 | 448 | bloc_ptr b = bloc; |
ad3bb3d2 | 449 | |
49f82b3d | 450 | /* No need to ever call this if arena is frozen, bug somewhere! */ |
177c0ea7 | 451 | if (r_alloc_freeze_level) |
1088b922 | 452 | emacs_abort (); |
49f82b3d | 453 | |
e429caa2 KH |
454 | while (b) |
455 | { | |
abe9ff32 RS |
456 | /* If bloc B won't fit within HEAP, |
457 | move to the next heap and try again. */ | |
91a211b5 | 458 | while (heap && (char *) address + b->size > (char *) heap->end) |
e429caa2 KH |
459 | { |
460 | heap = heap->next; | |
461 | if (heap == NIL_HEAP) | |
462 | break; | |
463 | address = heap->bloc_start; | |
464 | } | |
dcfdbac7 | 465 | |
abe9ff32 RS |
466 | /* If BLOC won't fit in any heap, |
467 | get enough new space to hold BLOC and all following blocs. */ | |
e429caa2 KH |
468 | if (heap == NIL_HEAP) |
469 | { | |
fcee5028 PE |
470 | bloc_ptr tb = b; |
471 | size_t s = 0; | |
e429caa2 | 472 | |
abe9ff32 | 473 | /* Add up the size of all the following blocs. */ |
e429caa2 KH |
474 | while (tb != NIL_BLOC) |
475 | { | |
177c0ea7 | 476 | if (tb->variable) |
49f82b3d RS |
477 | s += tb->size; |
478 | ||
e429caa2 KH |
479 | tb = tb->next; |
480 | } | |
481 | ||
abe9ff32 RS |
482 | /* Get that space. */ |
483 | address = obtain (address, s); | |
484 | if (address == 0) | |
e429caa2 KH |
485 | return 0; |
486 | ||
487 | heap = last_heap; | |
488 | } | |
489 | ||
abe9ff32 RS |
490 | /* Record the new address of this bloc |
491 | and update where the next bloc can start. */ | |
e429caa2 | 492 | b->new_data = address; |
177c0ea7 | 493 | if (b->variable) |
91a211b5 | 494 | address = (char *) address + b->size; |
e429caa2 KH |
495 | b = b->next; |
496 | } | |
497 | ||
498 | return 1; | |
499 | } | |
47f13333 RS |
500 | \f |
501 | /* Update the records of which heaps contain which blocs, starting | |
502 | with heap HEAP and bloc BLOC. */ | |
503 | ||
504 | static void | |
971de7fb | 505 | update_heap_bloc_correspondence (bloc_ptr bloc, heap_ptr heap) |
abe9ff32 RS |
506 | { |
507 | register bloc_ptr b; | |
508 | ||
47f13333 RS |
509 | /* Initialize HEAP's status to reflect blocs before BLOC. */ |
510 | if (bloc != NIL_BLOC && bloc->prev != NIL_BLOC && bloc->prev->heap == heap) | |
511 | { | |
512 | /* The previous bloc is in HEAP. */ | |
513 | heap->last_bloc = bloc->prev; | |
91a211b5 | 514 | heap->free = (char *) bloc->prev->data + bloc->prev->size; |
47f13333 RS |
515 | } |
516 | else | |
517 | { | |
518 | /* HEAP contains no blocs before BLOC. */ | |
519 | heap->first_bloc = NIL_BLOC; | |
520 | heap->last_bloc = NIL_BLOC; | |
521 | heap->free = heap->bloc_start; | |
522 | } | |
523 | ||
abe9ff32 RS |
524 | /* Advance through blocs one by one. */ |
525 | for (b = bloc; b != NIL_BLOC; b = b->next) | |
526 | { | |
47f13333 RS |
527 | /* Advance through heaps, marking them empty, |
528 | till we get to the one that B is in. */ | |
abe9ff32 RS |
529 | while (heap) |
530 | { | |
531 | if (heap->bloc_start <= b->data && b->data <= heap->end) | |
532 | break; | |
533 | heap = heap->next; | |
47f13333 RS |
534 | /* We know HEAP is not null now, |
535 | because there has to be space for bloc B. */ | |
536 | heap->first_bloc = NIL_BLOC; | |
537 | heap->last_bloc = NIL_BLOC; | |
abe9ff32 RS |
538 | heap->free = heap->bloc_start; |
539 | } | |
47f13333 RS |
540 | |
541 | /* Update HEAP's status for bloc B. */ | |
91a211b5 | 542 | heap->free = (char *) b->data + b->size; |
47f13333 RS |
543 | heap->last_bloc = b; |
544 | if (heap->first_bloc == NIL_BLOC) | |
545 | heap->first_bloc = b; | |
546 | ||
547 | /* Record that B is in HEAP. */ | |
548 | b->heap = heap; | |
abe9ff32 RS |
549 | } |
550 | ||
551 | /* If there are any remaining heaps and no blocs left, | |
47f13333 | 552 | mark those heaps as empty. */ |
abe9ff32 RS |
553 | heap = heap->next; |
554 | while (heap) | |
555 | { | |
47f13333 RS |
556 | heap->first_bloc = NIL_BLOC; |
557 | heap->last_bloc = NIL_BLOC; | |
abe9ff32 RS |
558 | heap->free = heap->bloc_start; |
559 | heap = heap->next; | |
560 | } | |
561 | } | |
47f13333 | 562 | \f |
abe9ff32 RS |
563 | /* Resize BLOC to SIZE bytes. This relocates the blocs |
564 | that come after BLOC in memory. */ | |
565 | ||
e429caa2 | 566 | static int |
fcee5028 | 567 | resize_bloc (bloc_ptr bloc, size_t size) |
dcfdbac7 | 568 | { |
fcee5028 | 569 | bloc_ptr b; |
e429caa2 | 570 | heap_ptr heap; |
fcee5028 PE |
571 | void *address; |
572 | size_t old_size; | |
e429caa2 | 573 | |
49f82b3d | 574 | /* No need to ever call this if arena is frozen, bug somewhere! */ |
177c0ea7 | 575 | if (r_alloc_freeze_level) |
1088b922 | 576 | emacs_abort (); |
49f82b3d | 577 | |
e429caa2 KH |
578 | if (bloc == NIL_BLOC || size == bloc->size) |
579 | return 1; | |
580 | ||
581 | for (heap = first_heap; heap != NIL_HEAP; heap = heap->next) | |
582 | { | |
583 | if (heap->bloc_start <= bloc->data && bloc->data <= heap->end) | |
584 | break; | |
585 | } | |
586 | ||
587 | if (heap == NIL_HEAP) | |
1088b922 | 588 | emacs_abort (); |
e429caa2 KH |
589 | |
590 | old_size = bloc->size; | |
591 | bloc->size = size; | |
592 | ||
abe9ff32 | 593 | /* Note that bloc could be moved into the previous heap. */ |
91a211b5 GM |
594 | address = (bloc->prev ? (char *) bloc->prev->data + bloc->prev->size |
595 | : (char *) first_heap->bloc_start); | |
e429caa2 KH |
596 | while (heap) |
597 | { | |
598 | if (heap->bloc_start <= address && address <= heap->end) | |
599 | break; | |
600 | heap = heap->prev; | |
601 | } | |
602 | ||
603 | if (! relocate_blocs (bloc, heap, address)) | |
604 | { | |
605 | bloc->size = old_size; | |
606 | return 0; | |
607 | } | |
608 | ||
609 | if (size > old_size) | |
610 | { | |
611 | for (b = last_bloc; b != bloc; b = b->prev) | |
612 | { | |
49f82b3d RS |
613 | if (!b->variable) |
614 | { | |
615 | b->size = 0; | |
616 | b->data = b->new_data; | |
177c0ea7 JB |
617 | } |
618 | else | |
49f82b3d | 619 | { |
78cef877 EZ |
620 | if (b->new_data != b->data) |
621 | memmove (b->new_data, b->data, b->size); | |
49f82b3d RS |
622 | *b->variable = b->data = b->new_data; |
623 | } | |
624 | } | |
625 | if (!bloc->variable) | |
626 | { | |
627 | bloc->size = 0; | |
628 | bloc->data = bloc->new_data; | |
629 | } | |
630 | else | |
631 | { | |
78cef877 EZ |
632 | if (bloc->new_data != bloc->data) |
633 | memmove (bloc->new_data, bloc->data, old_size); | |
3ce2f8ac | 634 | memset ((char *) bloc->new_data + old_size, 0, size - old_size); |
49f82b3d | 635 | *bloc->variable = bloc->data = bloc->new_data; |
e429caa2 | 636 | } |
e429caa2 KH |
637 | } |
638 | else | |
dcfdbac7 | 639 | { |
ad3bb3d2 JB |
640 | for (b = bloc; b != NIL_BLOC; b = b->next) |
641 | { | |
49f82b3d RS |
642 | if (!b->variable) |
643 | { | |
644 | b->size = 0; | |
645 | b->data = b->new_data; | |
177c0ea7 JB |
646 | } |
647 | else | |
49f82b3d | 648 | { |
78cef877 EZ |
649 | if (b->new_data != b->data) |
650 | memmove (b->new_data, b->data, b->size); | |
49f82b3d RS |
651 | *b->variable = b->data = b->new_data; |
652 | } | |
ad3bb3d2 | 653 | } |
ad3bb3d2 | 654 | } |
dcfdbac7 | 655 | |
47f13333 | 656 | update_heap_bloc_correspondence (bloc, heap); |
abe9ff32 | 657 | |
91a211b5 GM |
658 | break_value = (last_bloc ? (char *) last_bloc->data + last_bloc->size |
659 | : (char *) first_heap->bloc_start); | |
e429caa2 KH |
660 | return 1; |
661 | } | |
47f13333 | 662 | \f |
abe9ff32 RS |
663 | /* Free BLOC from the chain of blocs, relocating any blocs above it. |
664 | This may return space to the system. */ | |
dcfdbac7 JB |
665 | |
666 | static void | |
971de7fb | 667 | free_bloc (bloc_ptr bloc) |
dcfdbac7 | 668 | { |
47f13333 | 669 | heap_ptr heap = bloc->heap; |
36c46f8e | 670 | heap_ptr h; |
47f13333 | 671 | |
49f82b3d RS |
672 | if (r_alloc_freeze_level) |
673 | { | |
fcee5028 | 674 | bloc->variable = NULL; |
49f82b3d RS |
675 | return; |
676 | } | |
177c0ea7 | 677 | |
e429caa2 KH |
678 | resize_bloc (bloc, 0); |
679 | ||
dcfdbac7 JB |
680 | if (bloc == first_bloc && bloc == last_bloc) |
681 | { | |
682 | first_bloc = last_bloc = NIL_BLOC; | |
683 | } | |
684 | else if (bloc == last_bloc) | |
685 | { | |
686 | last_bloc = bloc->prev; | |
687 | last_bloc->next = NIL_BLOC; | |
688 | } | |
689 | else if (bloc == first_bloc) | |
690 | { | |
691 | first_bloc = bloc->next; | |
692 | first_bloc->prev = NIL_BLOC; | |
dcfdbac7 JB |
693 | } |
694 | else | |
695 | { | |
696 | bloc->next->prev = bloc->prev; | |
697 | bloc->prev->next = bloc->next; | |
dcfdbac7 JB |
698 | } |
699 | ||
36c46f8e EZ |
700 | /* Sometimes, 'heap' obtained from bloc->heap above is not really a |
701 | 'heap' structure. It can even be beyond the current break point, | |
702 | which will cause crashes when we dereference it below (see | |
703 | bug#12242). Evidently, the reason is bloc allocations done while | |
704 | use_relocatable_buffers was non-positive, because additional | |
705 | memory we get then is not recorded in the heaps we manage. If | |
706 | bloc->heap records such a "heap", we cannot (and don't need to) | |
707 | update its records. So we validate the 'heap' value by making | |
708 | sure it is one of the heaps we manage via the heaps linked list, | |
709 | and don't touch a 'heap' that isn't found there. This avoids | |
710 | accessing memory we know nothing about. */ | |
711 | for (h = first_heap; h != NIL_HEAP; h = h->next) | |
712 | if (heap == h) | |
713 | break; | |
714 | ||
715 | if (h) | |
47f13333 | 716 | { |
36c46f8e EZ |
717 | /* Update the records of which blocs are in HEAP. */ |
718 | if (heap->first_bloc == bloc) | |
719 | { | |
720 | if (bloc->next != 0 && bloc->next->heap == heap) | |
721 | heap->first_bloc = bloc->next; | |
722 | else | |
723 | heap->first_bloc = heap->last_bloc = NIL_BLOC; | |
724 | } | |
725 | if (heap->last_bloc == bloc) | |
726 | { | |
727 | if (bloc->prev != 0 && bloc->prev->heap == heap) | |
728 | heap->last_bloc = bloc->prev; | |
729 | else | |
730 | heap->first_bloc = heap->last_bloc = NIL_BLOC; | |
731 | } | |
47f13333 RS |
732 | } |
733 | ||
e429caa2 | 734 | relinquish (); |
dcfdbac7 JB |
735 | free (bloc); |
736 | } | |
737 | \f | |
956ace37 JB |
738 | /* Interface routines. */ |
739 | ||
98b7fe02 | 740 | /* Obtain SIZE bytes of storage from the free pool, or the system, as |
2c46d29f | 741 | necessary. If relocatable blocs are in use, this means relocating |
98b7fe02 JB |
742 | them. This function gets plugged into the GNU malloc's __morecore |
743 | hook. | |
744 | ||
7516b7d5 RS |
745 | We provide hysteresis, never relocating by less than extra_bytes. |
746 | ||
98b7fe02 JB |
747 | If we're out of memory, we should return zero, to imitate the other |
748 | __morecore hook values - in particular, __default_morecore in the | |
749 | GNU malloc package. */ | |
dcfdbac7 | 750 | |
fcee5028 | 751 | static void * |
62aba0d4 | 752 | r_alloc_sbrk (ptrdiff_t size) |
dcfdbac7 | 753 | { |
fcee5028 PE |
754 | bloc_ptr b; |
755 | void *address; | |
dcfdbac7 | 756 | |
44d3dec0 RS |
757 | if (! r_alloc_initialized) |
758 | r_alloc_init (); | |
759 | ||
e8a02204 | 760 | if (use_relocatable_buffers <= 0) |
fcee5028 | 761 | return real_morecore (size); |
dcfdbac7 | 762 | |
e429caa2 KH |
763 | if (size == 0) |
764 | return virtual_break_value; | |
7516b7d5 | 765 | |
e429caa2 | 766 | if (size > 0) |
dcfdbac7 | 767 | { |
abe9ff32 RS |
768 | /* Allocate a page-aligned space. GNU malloc would reclaim an |
769 | extra space if we passed an unaligned one. But we could | |
8e6208c5 | 770 | not always find a space which is contiguous to the previous. */ |
fcee5028 | 771 | void *new_bloc_start; |
e429caa2 | 772 | heap_ptr h = first_heap; |
fcee5028 | 773 | size_t get = ROUNDUP (size); |
7516b7d5 | 774 | |
fcee5028 | 775 | address = (void *) ROUNDUP (virtual_break_value); |
e429caa2 | 776 | |
abe9ff32 | 777 | /* Search the list upward for a heap which is large enough. */ |
fcee5028 | 778 | while ((char *) h->end < (char *) MEM_ROUNDUP ((char *) address + get)) |
e429caa2 KH |
779 | { |
780 | h = h->next; | |
781 | if (h == NIL_HEAP) | |
782 | break; | |
fcee5028 | 783 | address = (void *) ROUNDUP (h->start); |
e429caa2 KH |
784 | } |
785 | ||
abe9ff32 | 786 | /* If not found, obtain more space. */ |
e429caa2 KH |
787 | if (h == NIL_HEAP) |
788 | { | |
789 | get += extra_bytes + page_size; | |
790 | ||
49f82b3d | 791 | if (! obtain (address, get)) |
e429caa2 | 792 | return 0; |
98b7fe02 | 793 | |
e429caa2 | 794 | if (first_heap == last_heap) |
fcee5028 | 795 | address = (void *) ROUNDUP (virtual_break_value); |
e429caa2 | 796 | else |
fcee5028 | 797 | address = (void *) ROUNDUP (last_heap->start); |
e429caa2 KH |
798 | h = last_heap; |
799 | } | |
800 | ||
fcee5028 | 801 | new_bloc_start = (void *) MEM_ROUNDUP ((char *) address + get); |
e429caa2 KH |
802 | |
803 | if (first_heap->bloc_start < new_bloc_start) | |
804 | { | |
49f82b3d | 805 | /* This is no clean solution - no idea how to do it better. */ |
177c0ea7 | 806 | if (r_alloc_freeze_level) |
fcee5028 | 807 | return NULL; |
49f82b3d RS |
808 | |
809 | /* There is a bug here: if the above obtain call succeeded, but the | |
810 | relocate_blocs call below does not succeed, we need to free | |
811 | the memory that we got with obtain. */ | |
812 | ||
abe9ff32 | 813 | /* Move all blocs upward. */ |
49f82b3d | 814 | if (! relocate_blocs (first_bloc, h, new_bloc_start)) |
e429caa2 KH |
815 | return 0; |
816 | ||
fcee5028 | 817 | /* Note that (char *) (h + 1) <= (char *) new_bloc_start since |
e429caa2 | 818 | get >= page_size, so the following does not destroy the heap |
abe9ff32 | 819 | header. */ |
e429caa2 KH |
820 | for (b = last_bloc; b != NIL_BLOC; b = b->prev) |
821 | { | |
78cef877 EZ |
822 | if (b->new_data != b->data) |
823 | memmove (b->new_data, b->data, b->size); | |
e429caa2 KH |
824 | *b->variable = b->data = b->new_data; |
825 | } | |
826 | ||
827 | h->bloc_start = new_bloc_start; | |
abe9ff32 | 828 | |
47f13333 | 829 | update_heap_bloc_correspondence (first_bloc, h); |
e429caa2 | 830 | } |
e429caa2 KH |
831 | if (h != first_heap) |
832 | { | |
833 | /* Give up managing heaps below the one the new | |
abe9ff32 | 834 | virtual_break_value points to. */ |
e429caa2 KH |
835 | first_heap->prev = NIL_HEAP; |
836 | first_heap->next = h->next; | |
837 | first_heap->start = h->start; | |
838 | first_heap->end = h->end; | |
abe9ff32 | 839 | first_heap->free = h->free; |
47f13333 RS |
840 | first_heap->first_bloc = h->first_bloc; |
841 | first_heap->last_bloc = h->last_bloc; | |
e429caa2 KH |
842 | first_heap->bloc_start = h->bloc_start; |
843 | ||
844 | if (first_heap->next) | |
845 | first_heap->next->prev = first_heap; | |
846 | else | |
847 | last_heap = first_heap; | |
848 | } | |
849 | ||
72af86bd | 850 | memset (address, 0, size); |
dcfdbac7 | 851 | } |
e429caa2 | 852 | else /* size < 0 */ |
dcfdbac7 | 853 | { |
fcee5028 PE |
854 | size_t excess = ((char *) first_heap->bloc_start |
855 | - ((char *) virtual_break_value + size)); | |
e429caa2 KH |
856 | |
857 | address = virtual_break_value; | |
858 | ||
859 | if (r_alloc_freeze_level == 0 && excess > 2 * extra_bytes) | |
860 | { | |
861 | excess -= extra_bytes; | |
862 | first_heap->bloc_start | |
fcee5028 | 863 | = (void *) MEM_ROUNDUP ((char *) first_heap->bloc_start - excess); |
e429caa2 | 864 | |
abe9ff32 | 865 | relocate_blocs (first_bloc, first_heap, first_heap->bloc_start); |
7516b7d5 | 866 | |
e429caa2 KH |
867 | for (b = first_bloc; b != NIL_BLOC; b = b->next) |
868 | { | |
78cef877 EZ |
869 | if (b->new_data != b->data) |
870 | memmove (b->new_data, b->data, b->size); | |
e429caa2 KH |
871 | *b->variable = b->data = b->new_data; |
872 | } | |
873 | } | |
874 | ||
fcee5028 | 875 | if ((char *) virtual_break_value + size < (char *) first_heap->start) |
e429caa2 KH |
876 | { |
877 | /* We found an additional space below the first heap */ | |
fcee5028 | 878 | first_heap->start = (void *) ((char *) virtual_break_value + size); |
e429caa2 | 879 | } |
dcfdbac7 JB |
880 | } |
881 | ||
fcee5028 | 882 | virtual_break_value = (void *) ((char *) address + size); |
47f13333 | 883 | break_value = (last_bloc |
91a211b5 GM |
884 | ? (char *) last_bloc->data + last_bloc->size |
885 | : (char *) first_heap->bloc_start); | |
e429caa2 | 886 | if (size < 0) |
abe9ff32 | 887 | relinquish (); |
7516b7d5 | 888 | |
e429caa2 | 889 | return address; |
dcfdbac7 JB |
890 | } |
891 | ||
0a58f946 | 892 | |
dcfdbac7 JB |
893 | /* Allocate a relocatable bloc of storage of size SIZE. A pointer to |
894 | the data is returned in *PTR. PTR is thus the address of some variable | |
98b7fe02 JB |
895 | which will use the data area. |
896 | ||
49f82b3d | 897 | The allocation of 0 bytes is valid. |
f96f2c5b JB |
898 | In case r_alloc_freeze_level is set, a best fit of unused blocs could be |
899 | done before allocating a new area. Not yet done. | |
49f82b3d | 900 | |
98b7fe02 JB |
901 | If we can't allocate the necessary memory, set *PTR to zero, and |
902 | return zero. */ | |
dcfdbac7 | 903 | |
fcee5028 PE |
904 | void * |
905 | r_alloc (void **ptr, size_t size) | |
dcfdbac7 | 906 | { |
fcee5028 | 907 | bloc_ptr new_bloc; |
dcfdbac7 | 908 | |
2c46d29f RS |
909 | if (! r_alloc_initialized) |
910 | r_alloc_init (); | |
911 | ||
abe9ff32 | 912 | new_bloc = get_bloc (MEM_ROUNDUP (size)); |
98b7fe02 JB |
913 | if (new_bloc) |
914 | { | |
915 | new_bloc->variable = ptr; | |
916 | *ptr = new_bloc->data; | |
917 | } | |
918 | else | |
919 | *ptr = 0; | |
dcfdbac7 JB |
920 | |
921 | return *ptr; | |
922 | } | |
923 | ||
2c46d29f RS |
924 | /* Free a bloc of relocatable storage whose data is pointed to by PTR. |
925 | Store 0 in *PTR to show there's no block allocated. */ | |
dcfdbac7 JB |
926 | |
927 | void | |
fcee5028 | 928 | r_alloc_free (void **ptr) |
dcfdbac7 | 929 | { |
fcee5028 | 930 | bloc_ptr dead_bloc; |
dcfdbac7 | 931 | |
44d3dec0 RS |
932 | if (! r_alloc_initialized) |
933 | r_alloc_init (); | |
934 | ||
dcfdbac7 JB |
935 | dead_bloc = find_bloc (ptr); |
936 | if (dead_bloc == NIL_BLOC) | |
1088b922 | 937 | emacs_abort (); /* Double free? PTR not originally used to allocate? */ |
dcfdbac7 JB |
938 | |
939 | free_bloc (dead_bloc); | |
2c46d29f | 940 | *ptr = 0; |
719b242f | 941 | |
d5179acc | 942 | #ifdef emacs |
719b242f | 943 | refill_memory_reserve (); |
d5179acc | 944 | #endif |
dcfdbac7 JB |
945 | } |
946 | ||
16a5c729 | 947 | /* Given a pointer at address PTR to relocatable data, resize it to SIZE. |
98b7fe02 JB |
948 | Do this by shifting all blocks above this one up in memory, unless |
949 | SIZE is less than or equal to the current bloc size, in which case | |
950 | do nothing. | |
dcfdbac7 | 951 | |
f96f2c5b | 952 | In case r_alloc_freeze_level is set, a new bloc is allocated, and the |
8e6208c5 | 953 | memory copied to it. Not very efficient. We could traverse the |
49f82b3d RS |
954 | bloc_list for a best fit of free blocs first. |
955 | ||
98b7fe02 JB |
956 | Change *PTR to reflect the new bloc, and return this value. |
957 | ||
958 | If more memory cannot be allocated, then leave *PTR unchanged, and | |
959 | return zero. */ | |
dcfdbac7 | 960 | |
fcee5028 PE |
961 | void * |
962 | r_re_alloc (void **ptr, size_t size) | |
dcfdbac7 | 963 | { |
fcee5028 | 964 | bloc_ptr bloc; |
dcfdbac7 | 965 | |
44d3dec0 RS |
966 | if (! r_alloc_initialized) |
967 | r_alloc_init (); | |
968 | ||
49f82b3d RS |
969 | if (!*ptr) |
970 | return r_alloc (ptr, size); | |
177c0ea7 | 971 | if (!size) |
49f82b3d RS |
972 | { |
973 | r_alloc_free (ptr); | |
974 | return r_alloc (ptr, 0); | |
975 | } | |
976 | ||
16a5c729 JB |
977 | bloc = find_bloc (ptr); |
978 | if (bloc == NIL_BLOC) | |
1088b922 | 979 | emacs_abort (); /* Already freed? PTR not originally used to allocate? */ |
dcfdbac7 | 980 | |
177c0ea7 | 981 | if (size < bloc->size) |
49f82b3d RS |
982 | { |
983 | /* Wouldn't it be useful to actually resize the bloc here? */ | |
984 | /* I think so too, but not if it's too expensive... */ | |
177c0ea7 JB |
985 | if ((bloc->size - MEM_ROUNDUP (size) >= page_size) |
986 | && r_alloc_freeze_level == 0) | |
49f82b3d RS |
987 | { |
988 | resize_bloc (bloc, MEM_ROUNDUP (size)); | |
989 | /* Never mind if this fails, just do nothing... */ | |
990 | /* It *should* be infallible! */ | |
991 | } | |
992 | } | |
993 | else if (size > bloc->size) | |
994 | { | |
995 | if (r_alloc_freeze_level) | |
996 | { | |
997 | bloc_ptr new_bloc; | |
998 | new_bloc = get_bloc (MEM_ROUNDUP (size)); | |
999 | if (new_bloc) | |
1000 | { | |
1001 | new_bloc->variable = ptr; | |
1002 | *ptr = new_bloc->data; | |
fcee5028 | 1003 | bloc->variable = NULL; |
49f82b3d RS |
1004 | } |
1005 | else | |
fcee5028 | 1006 | return NULL; |
49f82b3d | 1007 | } |
177c0ea7 | 1008 | else |
49f82b3d RS |
1009 | { |
1010 | if (! resize_bloc (bloc, MEM_ROUNDUP (size))) | |
fcee5028 | 1011 | return NULL; |
49f82b3d RS |
1012 | } |
1013 | } | |
dcfdbac7 JB |
1014 | return *ptr; |
1015 | } | |
81bd58e8 | 1016 | |
dec41418 RS |
1017 | |
1018 | #if defined (emacs) && defined (DOUG_LEA_MALLOC) | |
1019 | ||
1020 | /* Reinitialize the morecore hook variables after restarting a dumped | |
1021 | Emacs. This is needed when using Doug Lea's malloc from GNU libc. */ | |
1022 | void | |
971de7fb | 1023 | r_alloc_reinit (void) |
dec41418 RS |
1024 | { |
1025 | /* Only do this if the hook has been reset, so that we don't get an | |
1026 | infinite loop, in case Emacs was linked statically. */ | |
1027 | if (__morecore != r_alloc_sbrk) | |
1028 | { | |
1029 | real_morecore = __morecore; | |
1030 | __morecore = r_alloc_sbrk; | |
1031 | } | |
1032 | } | |
0a58f946 GM |
1033 | |
1034 | #endif /* emacs && DOUG_LEA_MALLOC */ | |
dec41418 | 1035 | |
e429caa2 | 1036 | #ifdef DEBUG |
0a58f946 | 1037 | |
e429caa2 KH |
1038 | #include <assert.h> |
1039 | ||
44d3dec0 | 1040 | void |
268c2c36 | 1041 | r_alloc_check (void) |
e429caa2 | 1042 | { |
6d16dd06 RS |
1043 | int found = 0; |
1044 | heap_ptr h, ph = 0; | |
1045 | bloc_ptr b, pb = 0; | |
1046 | ||
1047 | if (!r_alloc_initialized) | |
1048 | return; | |
1049 | ||
1050 | assert (first_heap); | |
fcee5028 PE |
1051 | assert (last_heap->end <= (void *) sbrk (0)); |
1052 | assert ((void *) first_heap < first_heap->start); | |
6d16dd06 RS |
1053 | assert (first_heap->start <= virtual_break_value); |
1054 | assert (virtual_break_value <= first_heap->end); | |
1055 | ||
1056 | for (h = first_heap; h; h = h->next) | |
1057 | { | |
1058 | assert (h->prev == ph); | |
fcee5028 | 1059 | assert ((void *) ROUNDUP (h->end) == h->end); |
40f3f04b RS |
1060 | #if 0 /* ??? The code in ralloc.c does not really try to ensure |
1061 | the heap start has any sort of alignment. | |
1062 | Perhaps it should. */ | |
fcee5028 | 1063 | assert ((void *) MEM_ROUNDUP (h->start) == h->start); |
40f3f04b | 1064 | #endif |
fcee5028 | 1065 | assert ((void *) MEM_ROUNDUP (h->bloc_start) == h->bloc_start); |
6d16dd06 RS |
1066 | assert (h->start <= h->bloc_start && h->bloc_start <= h->end); |
1067 | ||
1068 | if (ph) | |
1069 | { | |
1070 | assert (ph->end < h->start); | |
fcee5028 | 1071 | assert (h->start <= (void *) h && (void *) (h + 1) <= h->bloc_start); |
6d16dd06 RS |
1072 | } |
1073 | ||
1074 | if (h->bloc_start <= break_value && break_value <= h->end) | |
1075 | found = 1; | |
1076 | ||
1077 | ph = h; | |
1078 | } | |
1079 | ||
1080 | assert (found); | |
1081 | assert (last_heap == ph); | |
1082 | ||
1083 | for (b = first_bloc; b; b = b->next) | |
1084 | { | |
1085 | assert (b->prev == pb); | |
fcee5028 PE |
1086 | assert ((void *) MEM_ROUNDUP (b->data) == b->data); |
1087 | assert ((size_t) MEM_ROUNDUP (b->size) == b->size); | |
6d16dd06 RS |
1088 | |
1089 | ph = 0; | |
1090 | for (h = first_heap; h; h = h->next) | |
1091 | { | |
1092 | if (h->bloc_start <= b->data && b->data + b->size <= h->end) | |
1093 | break; | |
1094 | ph = h; | |
1095 | } | |
1096 | ||
1097 | assert (h); | |
1098 | ||
1099 | if (pb && pb->data + pb->size != b->data) | |
1100 | { | |
1101 | assert (ph && b->data == h->bloc_start); | |
1102 | while (ph) | |
1103 | { | |
1104 | if (ph->bloc_start <= pb->data | |
1105 | && pb->data + pb->size <= ph->end) | |
1106 | { | |
1107 | assert (pb->data + pb->size + b->size > ph->end); | |
1108 | break; | |
1109 | } | |
1110 | else | |
1111 | { | |
1112 | assert (ph->bloc_start + b->size > ph->end); | |
1113 | } | |
1114 | ph = ph->prev; | |
1115 | } | |
1116 | } | |
1117 | pb = b; | |
1118 | } | |
1119 | ||
1120 | assert (last_bloc == pb); | |
1121 | ||
1122 | if (last_bloc) | |
1123 | assert (last_bloc->data + last_bloc->size == break_value); | |
1124 | else | |
1125 | assert (first_heap->bloc_start == break_value); | |
e429caa2 | 1126 | } |
0a58f946 | 1127 | |
e429caa2 | 1128 | #endif /* DEBUG */ |
0a58f946 | 1129 | |
baae5c2d JR |
1130 | /* Update the internal record of which variable points to some data to NEW. |
1131 | Used by buffer-swap-text in Emacs to restore consistency after it | |
1132 | swaps the buffer text between two buffer objects. The OLD pointer | |
1133 | is checked to ensure that memory corruption does not occur due to | |
1134 | misuse. */ | |
1135 | void | |
fcee5028 | 1136 | r_alloc_reset_variable (void **old, void **new) |
baae5c2d JR |
1137 | { |
1138 | bloc_ptr bloc = first_bloc; | |
1139 | ||
1140 | /* Find the bloc that corresponds to the data pointed to by pointer. | |
1141 | find_bloc cannot be used, as it has internal consistency checks | |
0d26e0b6 | 1142 | which fail when the variable needs resetting. */ |
baae5c2d JR |
1143 | while (bloc != NIL_BLOC) |
1144 | { | |
1145 | if (bloc->data == *new) | |
1146 | break; | |
1147 | ||
1148 | bloc = bloc->next; | |
1149 | } | |
1150 | ||
1151 | if (bloc == NIL_BLOC || bloc->variable != old) | |
1088b922 | 1152 | emacs_abort (); /* Already freed? OLD not originally used to allocate? */ |
baae5c2d JR |
1153 | |
1154 | /* Update variable to point to the new location. */ | |
1155 | bloc->variable = new; | |
1156 | } | |
0a58f946 | 1157 | |
52c55cc7 EZ |
1158 | void |
1159 | r_alloc_inhibit_buffer_relocation (int inhibit) | |
1160 | { | |
e8a02204 EZ |
1161 | if (use_relocatable_buffers > 1) |
1162 | use_relocatable_buffers = 1; | |
291d430f | 1163 | if (inhibit) |
291d430f | 1164 | use_relocatable_buffers--; |
e8a02204 EZ |
1165 | else if (use_relocatable_buffers < 1) |
1166 | use_relocatable_buffers++; | |
52c55cc7 EZ |
1167 | } |
1168 | ||
0a58f946 GM |
1169 | \f |
1170 | /*********************************************************************** | |
1171 | Initialization | |
1172 | ***********************************************************************/ | |
1173 | ||
0a58f946 GM |
1174 | /* Initialize various things for memory allocation. */ |
1175 | ||
1176 | static void | |
971de7fb | 1177 | r_alloc_init (void) |
0a58f946 GM |
1178 | { |
1179 | if (r_alloc_initialized) | |
1180 | return; | |
0a58f946 | 1181 | r_alloc_initialized = 1; |
177c0ea7 | 1182 | |
a2c23c92 DL |
1183 | page_size = PAGE; |
1184 | #ifndef SYSTEM_MALLOC | |
0a58f946 GM |
1185 | real_morecore = __morecore; |
1186 | __morecore = r_alloc_sbrk; | |
1187 | ||
1188 | first_heap = last_heap = &heap_base; | |
1189 | first_heap->next = first_heap->prev = NIL_HEAP; | |
1190 | first_heap->start = first_heap->bloc_start | |
fcee5028 PE |
1191 | = virtual_break_value = break_value = real_morecore (0); |
1192 | if (break_value == NULL) | |
1088b922 | 1193 | emacs_abort (); |
0a58f946 | 1194 | |
0a58f946 | 1195 | extra_bytes = ROUNDUP (50000); |
a2c23c92 | 1196 | #endif |
0a58f946 GM |
1197 | |
1198 | #ifdef DOUG_LEA_MALLOC | |
4d7e6e51 | 1199 | block_input (); |
1673df2e | 1200 | mallopt (M_TOP_PAD, 64 * 4096); |
4d7e6e51 | 1201 | unblock_input (); |
0a58f946 | 1202 | #else |
a2c23c92 | 1203 | #ifndef SYSTEM_MALLOC |
45ba16c7 EZ |
1204 | /* Give GNU malloc's morecore some hysteresis so that we move all |
1205 | the relocatable blocks much less often. The number used to be | |
1206 | 64, but alloc.c would override that with 32 in code that was | |
1207 | removed when SYNC_INPUT became the only input handling mode. | |
9b318728 | 1208 | That code was conditioned on !DOUG_LEA_MALLOC, so the call to |
45ba16c7 EZ |
1209 | mallopt above is left unchanged. (Actually, I think there's no |
1210 | system nowadays that uses DOUG_LEA_MALLOC and also uses | |
1211 | REL_ALLOC.) */ | |
1212 | __malloc_extra_blocks = 32; | |
0a58f946 | 1213 | #endif |
a2c23c92 | 1214 | #endif |
0a58f946 | 1215 | |
5ad25b24 | 1216 | #ifndef SYSTEM_MALLOC |
fcee5028 | 1217 | first_heap->end = (void *) ROUNDUP (first_heap->start); |
0a58f946 GM |
1218 | |
1219 | /* The extra call to real_morecore guarantees that the end of the | |
1220 | address space is a multiple of page_size, even if page_size is | |
1221 | not really the page size of the system running the binary in | |
1222 | which page_size is stored. This allows a binary to be built on a | |
1223 | system with one page size and run on a system with a smaller page | |
1224 | size. */ | |
fcee5028 | 1225 | real_morecore ((char *) first_heap->end - (char *) first_heap->start); |
0a58f946 GM |
1226 | |
1227 | /* Clear the rest of the last page; this memory is in our address space | |
1228 | even though it is after the sbrk value. */ | |
1229 | /* Doubly true, with the additional call that explicitly adds the | |
1230 | rest of that page to the address space. */ | |
72af86bd AS |
1231 | memset (first_heap->start, 0, |
1232 | (char *) first_heap->end - (char *) first_heap->start); | |
0a58f946 | 1233 | virtual_break_value = break_value = first_heap->bloc_start = first_heap->end; |
a2c23c92 | 1234 | #endif |
177c0ea7 | 1235 | |
0a58f946 GM |
1236 | use_relocatable_buffers = 1; |
1237 | } |