Commit | Line | Data |
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177c0ea7 | 1 | /* Block-relocating memory allocator. |
429ab54e | 2 | Copyright (C) 1993, 1995, 2000, 2001, 2002, 2003, 2004, |
8cabe764 | 3 | 2005, 2006, 2007, 2008 Free Software Foundation, Inc. |
dcfdbac7 JB |
4 | |
5 | This file is part of GNU Emacs. | |
6 | ||
9ec0b715 | 7 | GNU Emacs is free software: you can redistribute it and/or modify |
dcfdbac7 | 8 | it under the terms of the GNU General Public License as published by |
9ec0b715 GM |
9 | the Free Software Foundation, either version 3 of the License, or |
10 | (at your option) any later version. | |
dcfdbac7 JB |
11 | |
12 | GNU Emacs is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
9ec0b715 | 18 | along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ |
dcfdbac7 JB |
19 | |
20 | /* NOTES: | |
21 | ||
eb8c3be9 | 22 | Only relocate the blocs necessary for SIZE in r_alloc_sbrk, |
dcfdbac7 | 23 | rather than all of them. This means allowing for a possible |
abe9ff32 | 24 | hole between the first bloc and the end of malloc storage. */ |
dcfdbac7 | 25 | |
2c46d29f | 26 | #ifdef emacs |
aef4d570 | 27 | |
18160b98 | 28 | #include <config.h> |
956ace37 | 29 | #include "lisp.h" /* Needed for VALBITS. */ |
a4766fd5 | 30 | #include "blockinput.h" |
0a58f946 | 31 | |
642a1733 DL |
32 | #ifdef HAVE_UNISTD_H |
33 | #include <unistd.h> | |
34 | #endif | |
a8c0e5ea | 35 | |
0a58f946 GM |
36 | typedef POINTER_TYPE *POINTER; |
37 | typedef size_t SIZE; | |
f275fd9a | 38 | |
2c46d29f RS |
39 | /* Declared in dispnew.c, this version doesn't screw up if regions |
40 | overlap. */ | |
0a58f946 | 41 | |
2c46d29f | 42 | extern void safe_bcopy (); |
2c46d29f | 43 | |
b0119c68 | 44 | #ifdef DOUG_LEA_MALLOC |
177c0ea7 | 45 | #define M_TOP_PAD -2 |
b0119c68 | 46 | extern int mallopt (); |
0a58f946 | 47 | #else /* not DOUG_LEA_MALLOC */ |
a2c23c92 | 48 | #ifndef SYSTEM_MALLOC |
b1685c5f | 49 | extern size_t __malloc_extra_blocks; |
a2c23c92 | 50 | #endif /* SYSTEM_MALLOC */ |
0a58f946 | 51 | #endif /* not DOUG_LEA_MALLOC */ |
49081834 | 52 | |
d5179acc | 53 | #else /* not emacs */ |
aef4d570 | 54 | |
2c46d29f | 55 | #include <stddef.h> |
aef4d570 | 56 | |
2c46d29f RS |
57 | typedef size_t SIZE; |
58 | typedef void *POINTER; | |
aef4d570 | 59 | |
aef4d570 RM |
60 | #include <unistd.h> |
61 | #include <malloc.h> | |
aef4d570 | 62 | |
2c46d29f | 63 | #define safe_bcopy(x, y, z) memmove (y, x, z) |
d5179acc RS |
64 | #define bzero(x, len) memset (x, 0, len) |
65 | ||
66 | #endif /* not emacs */ | |
2c46d29f | 67 | |
0a58f946 | 68 | |
d5179acc | 69 | #include "getpagesize.h" |
dcfdbac7 JB |
70 | |
71 | #define NIL ((POINTER) 0) | |
72 | ||
2c46d29f RS |
73 | /* A flag to indicate whether we have initialized ralloc yet. For |
74 | Emacs's sake, please do not make this local to malloc_init; on some | |
75 | machines, the dumping procedure makes all static variables | |
76 | read-only. On these machines, the word static is #defined to be | |
77 | the empty string, meaning that r_alloc_initialized becomes an | |
0a58f946 GM |
78 | automatic variable, and loses its value each time Emacs is started |
79 | up. */ | |
80 | ||
2c46d29f RS |
81 | static int r_alloc_initialized = 0; |
82 | ||
83 | static void r_alloc_init (); | |
0a58f946 | 84 | |
dcfdbac7 | 85 | \f |
956ace37 JB |
86 | /* Declarations for working with the malloc, ralloc, and system breaks. */ |
87 | ||
abe9ff32 | 88 | /* Function to set the real break value. */ |
321ed47b | 89 | POINTER (*real_morecore) (); |
dcfdbac7 | 90 | |
abe9ff32 | 91 | /* The break value, as seen by malloc. */ |
dcfdbac7 JB |
92 | static POINTER virtual_break_value; |
93 | ||
abe9ff32 RS |
94 | /* The address of the end of the last data in use by ralloc, |
95 | including relocatable blocs as well as malloc data. */ | |
dcfdbac7 JB |
96 | static POINTER break_value; |
97 | ||
7516b7d5 RS |
98 | /* This is the size of a page. We round memory requests to this boundary. */ |
99 | static int page_size; | |
100 | ||
177c0ea7 | 101 | /* Whenever we get memory from the system, get this many extra bytes. This |
ad3bb3d2 | 102 | must be a multiple of page_size. */ |
7516b7d5 RS |
103 | static int extra_bytes; |
104 | ||
dcfdbac7 | 105 | /* Macros for rounding. Note that rounding to any value is possible |
abe9ff32 | 106 | by changing the definition of PAGE. */ |
dcfdbac7 | 107 | #define PAGE (getpagesize ()) |
f7a009a5 RM |
108 | #define ALIGNED(addr) (((unsigned long int) (addr) & (page_size - 1)) == 0) |
109 | #define ROUNDUP(size) (((unsigned long int) (size) + page_size - 1) \ | |
110 | & ~(page_size - 1)) | |
7516b7d5 | 111 | #define ROUND_TO_PAGE(addr) (addr & (~(page_size - 1))) |
e429caa2 KH |
112 | |
113 | #define MEM_ALIGN sizeof(double) | |
114 | #define MEM_ROUNDUP(addr) (((unsigned long int)(addr) + MEM_ALIGN - 1) \ | |
115 | & ~(MEM_ALIGN - 1)) | |
0a58f946 | 116 | |
aeac019e GM |
117 | /* The hook `malloc' uses for the function which gets more space |
118 | from the system. */ | |
119 | ||
120 | #ifndef SYSTEM_MALLOC | |
121 | extern POINTER (*__morecore) (); | |
122 | #endif | |
123 | ||
124 | ||
e429caa2 | 125 | \f |
0a58f946 GM |
126 | /*********************************************************************** |
127 | Implementation using sbrk | |
128 | ***********************************************************************/ | |
129 | ||
abe9ff32 RS |
130 | /* Data structures of heaps and blocs. */ |
131 | ||
132 | /* The relocatable objects, or blocs, and the malloc data | |
133 | both reside within one or more heaps. | |
134 | Each heap contains malloc data, running from `start' to `bloc_start', | |
135 | and relocatable objects, running from `bloc_start' to `free'. | |
136 | ||
137 | Relocatable objects may relocate within the same heap | |
138 | or may move into another heap; the heaps themselves may grow | |
139 | but they never move. | |
140 | ||
141 | We try to make just one heap and make it larger as necessary. | |
8e6208c5 | 142 | But sometimes we can't do that, because we can't get contiguous |
abe9ff32 | 143 | space to add onto the heap. When that happens, we start a new heap. */ |
177c0ea7 | 144 | |
e429caa2 KH |
145 | typedef struct heap |
146 | { | |
147 | struct heap *next; | |
148 | struct heap *prev; | |
abe9ff32 | 149 | /* Start of memory range of this heap. */ |
e429caa2 | 150 | POINTER start; |
abe9ff32 | 151 | /* End of memory range of this heap. */ |
e429caa2 | 152 | POINTER end; |
abe9ff32 RS |
153 | /* Start of relocatable data in this heap. */ |
154 | POINTER bloc_start; | |
155 | /* Start of unused space in this heap. */ | |
156 | POINTER free; | |
47f13333 RS |
157 | /* First bloc in this heap. */ |
158 | struct bp *first_bloc; | |
159 | /* Last bloc in this heap. */ | |
160 | struct bp *last_bloc; | |
e429caa2 KH |
161 | } *heap_ptr; |
162 | ||
163 | #define NIL_HEAP ((heap_ptr) 0) | |
164 | #define HEAP_PTR_SIZE (sizeof (struct heap)) | |
165 | ||
abe9ff32 RS |
166 | /* This is the first heap object. |
167 | If we need additional heap objects, each one resides at the beginning of | |
168 | the space it covers. */ | |
169 | static struct heap heap_base; | |
170 | ||
171 | /* Head and tail of the list of heaps. */ | |
e429caa2 KH |
172 | static heap_ptr first_heap, last_heap; |
173 | ||
174 | /* These structures are allocated in the malloc arena. | |
175 | The linked list is kept in order of increasing '.data' members. | |
176 | The data blocks abut each other; if b->next is non-nil, then | |
177c0ea7 | 177 | b->data + b->size == b->next->data. |
49f82b3d RS |
178 | |
179 | An element with variable==NIL denotes a freed block, which has not yet | |
180 | been collected. They may only appear while r_alloc_freeze > 0, and will be | |
181 | freed when the arena is thawed. Currently, these blocs are not reusable, | |
8e6208c5 | 182 | while the arena is frozen. Very inefficient. */ |
49f82b3d | 183 | |
e429caa2 KH |
184 | typedef struct bp |
185 | { | |
186 | struct bp *next; | |
187 | struct bp *prev; | |
188 | POINTER *variable; | |
189 | POINTER data; | |
190 | SIZE size; | |
8e6208c5 | 191 | POINTER new_data; /* temporarily used for relocation */ |
49f82b3d | 192 | struct heap *heap; /* Heap this bloc is in. */ |
e429caa2 KH |
193 | } *bloc_ptr; |
194 | ||
195 | #define NIL_BLOC ((bloc_ptr) 0) | |
196 | #define BLOC_PTR_SIZE (sizeof (struct bp)) | |
197 | ||
abe9ff32 | 198 | /* Head and tail of the list of relocatable blocs. */ |
e429caa2 KH |
199 | static bloc_ptr first_bloc, last_bloc; |
200 | ||
49f82b3d RS |
201 | static int use_relocatable_buffers; |
202 | ||
203 | /* If >0, no relocation whatsoever takes place. */ | |
204 | static int r_alloc_freeze_level; | |
205 | ||
dcfdbac7 | 206 | \f |
956ace37 JB |
207 | /* Functions to get and return memory from the system. */ |
208 | ||
abe9ff32 RS |
209 | /* Find the heap that ADDRESS falls within. */ |
210 | ||
211 | static heap_ptr | |
212 | find_heap (address) | |
213 | POINTER address; | |
214 | { | |
215 | heap_ptr heap; | |
216 | ||
217 | for (heap = last_heap; heap; heap = heap->prev) | |
218 | { | |
219 | if (heap->start <= address && address <= heap->end) | |
220 | return heap; | |
221 | } | |
222 | ||
223 | return NIL_HEAP; | |
224 | } | |
225 | ||
226 | /* Find SIZE bytes of space in a heap. | |
227 | Try to get them at ADDRESS (which must fall within some heap's range) | |
228 | if we can get that many within one heap. | |
229 | ||
e429caa2 | 230 | If enough space is not presently available in our reserve, this means |
8e6208c5 KH |
231 | getting more page-aligned space from the system. If the returned space |
232 | is not contiguous to the last heap, allocate a new heap, and append it | |
abe9ff32 RS |
233 | |
234 | obtain does not try to keep track of whether space is in use | |
235 | or not in use. It just returns the address of SIZE bytes that | |
236 | fall within a single heap. If you call obtain twice in a row | |
237 | with the same arguments, you typically get the same value. | |
238 | to the heap list. It's the caller's responsibility to keep | |
239 | track of what space is in use. | |
dcfdbac7 | 240 | |
e429caa2 KH |
241 | Return the address of the space if all went well, or zero if we couldn't |
242 | allocate the memory. */ | |
abe9ff32 | 243 | |
e429caa2 KH |
244 | static POINTER |
245 | obtain (address, size) | |
246 | POINTER address; | |
247 | SIZE size; | |
dcfdbac7 | 248 | { |
e429caa2 KH |
249 | heap_ptr heap; |
250 | SIZE already_available; | |
dcfdbac7 | 251 | |
abe9ff32 | 252 | /* Find the heap that ADDRESS falls within. */ |
e429caa2 | 253 | for (heap = last_heap; heap; heap = heap->prev) |
dcfdbac7 | 254 | { |
e429caa2 KH |
255 | if (heap->start <= address && address <= heap->end) |
256 | break; | |
257 | } | |
dcfdbac7 | 258 | |
e429caa2 | 259 | if (! heap) |
abe9ff32 | 260 | abort (); |
dcfdbac7 | 261 | |
abe9ff32 RS |
262 | /* If we can't fit SIZE bytes in that heap, |
263 | try successive later heaps. */ | |
91a211b5 | 264 | while (heap && (char *) address + size > (char *) heap->end) |
e429caa2 KH |
265 | { |
266 | heap = heap->next; | |
267 | if (heap == NIL_HEAP) | |
268 | break; | |
269 | address = heap->bloc_start; | |
dcfdbac7 JB |
270 | } |
271 | ||
abe9ff32 RS |
272 | /* If we can't fit them within any existing heap, |
273 | get more space. */ | |
e429caa2 KH |
274 | if (heap == NIL_HEAP) |
275 | { | |
276 | POINTER new = (*real_morecore)(0); | |
277 | SIZE get; | |
98b7fe02 | 278 | |
e429caa2 | 279 | already_available = (char *)last_heap->end - (char *)address; |
dcfdbac7 | 280 | |
e429caa2 KH |
281 | if (new != last_heap->end) |
282 | { | |
abe9ff32 RS |
283 | /* Someone else called sbrk. Make a new heap. */ |
284 | ||
285 | heap_ptr new_heap = (heap_ptr) MEM_ROUNDUP (new); | |
286 | POINTER bloc_start = (POINTER) MEM_ROUNDUP ((POINTER)(new_heap + 1)); | |
e429caa2 | 287 | |
91a211b5 | 288 | if ((*real_morecore) ((char *) bloc_start - (char *) new) != new) |
e429caa2 KH |
289 | return 0; |
290 | ||
291 | new_heap->start = new; | |
292 | new_heap->end = bloc_start; | |
293 | new_heap->bloc_start = bloc_start; | |
abe9ff32 | 294 | new_heap->free = bloc_start; |
e429caa2 KH |
295 | new_heap->next = NIL_HEAP; |
296 | new_heap->prev = last_heap; | |
47f13333 RS |
297 | new_heap->first_bloc = NIL_BLOC; |
298 | new_heap->last_bloc = NIL_BLOC; | |
e429caa2 KH |
299 | last_heap->next = new_heap; |
300 | last_heap = new_heap; | |
301 | ||
302 | address = bloc_start; | |
303 | already_available = 0; | |
304 | } | |
dcfdbac7 | 305 | |
abe9ff32 RS |
306 | /* Add space to the last heap (which we may have just created). |
307 | Get some extra, so we can come here less often. */ | |
308 | ||
e429caa2 | 309 | get = size + extra_bytes - already_available; |
abe9ff32 | 310 | get = (char *) ROUNDUP ((char *)last_heap->end + get) |
e429caa2 | 311 | - (char *) last_heap->end; |
dcfdbac7 | 312 | |
e429caa2 KH |
313 | if ((*real_morecore) (get) != last_heap->end) |
314 | return 0; | |
315 | ||
91a211b5 | 316 | last_heap->end = (char *) last_heap->end + get; |
e429caa2 KH |
317 | } |
318 | ||
319 | return address; | |
320 | } | |
dcfdbac7 | 321 | |
abe9ff32 RS |
322 | /* Return unused heap space to the system |
323 | if there is a lot of unused space now. | |
324 | This can make the last heap smaller; | |
325 | it can also eliminate the last heap entirely. */ | |
326 | ||
dcfdbac7 | 327 | static void |
e429caa2 | 328 | relinquish () |
dcfdbac7 | 329 | { |
e429caa2 | 330 | register heap_ptr h; |
8d31e373 | 331 | long excess = 0; |
e429caa2 | 332 | |
abe9ff32 RS |
333 | /* Add the amount of space beyond break_value |
334 | in all heaps which have extend beyond break_value at all. */ | |
335 | ||
e429caa2 KH |
336 | for (h = last_heap; h && break_value < h->end; h = h->prev) |
337 | { | |
338 | excess += (char *) h->end - (char *) ((break_value < h->bloc_start) | |
339 | ? h->bloc_start : break_value); | |
340 | } | |
341 | ||
342 | if (excess > extra_bytes * 2 && (*real_morecore) (0) == last_heap->end) | |
dcfdbac7 | 343 | { |
7516b7d5 RS |
344 | /* Keep extra_bytes worth of empty space. |
345 | And don't free anything unless we can free at least extra_bytes. */ | |
e429caa2 | 346 | excess -= extra_bytes; |
dcfdbac7 | 347 | |
e429caa2 KH |
348 | if ((char *)last_heap->end - (char *)last_heap->bloc_start <= excess) |
349 | { | |
47f13333 RS |
350 | /* This heap should have no blocs in it. */ |
351 | if (last_heap->first_bloc != NIL_BLOC | |
352 | || last_heap->last_bloc != NIL_BLOC) | |
353 | abort (); | |
354 | ||
abe9ff32 | 355 | /* Return the last heap, with its header, to the system. */ |
e429caa2 KH |
356 | excess = (char *)last_heap->end - (char *)last_heap->start; |
357 | last_heap = last_heap->prev; | |
358 | last_heap->next = NIL_HEAP; | |
359 | } | |
360 | else | |
361 | { | |
362 | excess = (char *) last_heap->end | |
abe9ff32 | 363 | - (char *) ROUNDUP ((char *)last_heap->end - excess); |
91a211b5 | 364 | last_heap->end = (char *) last_heap->end - excess; |
e429caa2 | 365 | } |
dcfdbac7 | 366 | |
e429caa2 | 367 | if ((*real_morecore) (- excess) == 0) |
21532667 KH |
368 | { |
369 | /* If the system didn't want that much memory back, adjust | |
370 | the end of the last heap to reflect that. This can occur | |
371 | if break_value is still within the original data segment. */ | |
91a211b5 | 372 | last_heap->end = (char *) last_heap->end + excess; |
21532667 KH |
373 | /* Make sure that the result of the adjustment is accurate. |
374 | It should be, for the else clause above; the other case, | |
375 | which returns the entire last heap to the system, seems | |
376 | unlikely to trigger this mode of failure. */ | |
377 | if (last_heap->end != (*real_morecore) (0)) | |
378 | abort (); | |
379 | } | |
e429caa2 | 380 | } |
dcfdbac7 | 381 | } |
719b242f RS |
382 | |
383 | /* Return the total size in use by relocating allocator, | |
384 | above where malloc gets space. */ | |
385 | ||
386 | long | |
387 | r_alloc_size_in_use () | |
388 | { | |
91a211b5 | 389 | return (char *) break_value - (char *) virtual_break_value; |
719b242f | 390 | } |
dcfdbac7 | 391 | \f |
956ace37 JB |
392 | /* The meat - allocating, freeing, and relocating blocs. */ |
393 | ||
956ace37 | 394 | /* Find the bloc referenced by the address in PTR. Returns a pointer |
abe9ff32 | 395 | to that block. */ |
dcfdbac7 JB |
396 | |
397 | static bloc_ptr | |
398 | find_bloc (ptr) | |
399 | POINTER *ptr; | |
400 | { | |
401 | register bloc_ptr p = first_bloc; | |
402 | ||
403 | while (p != NIL_BLOC) | |
404 | { | |
405 | if (p->variable == ptr && p->data == *ptr) | |
406 | return p; | |
407 | ||
408 | p = p->next; | |
409 | } | |
410 | ||
411 | return p; | |
412 | } | |
413 | ||
414 | /* Allocate a bloc of SIZE bytes and append it to the chain of blocs. | |
98b7fe02 JB |
415 | Returns a pointer to the new bloc, or zero if we couldn't allocate |
416 | memory for the new block. */ | |
dcfdbac7 JB |
417 | |
418 | static bloc_ptr | |
419 | get_bloc (size) | |
420 | SIZE size; | |
421 | { | |
98b7fe02 | 422 | register bloc_ptr new_bloc; |
abe9ff32 | 423 | register heap_ptr heap; |
98b7fe02 JB |
424 | |
425 | if (! (new_bloc = (bloc_ptr) malloc (BLOC_PTR_SIZE)) | |
e429caa2 | 426 | || ! (new_bloc->data = obtain (break_value, size))) |
98b7fe02 | 427 | { |
c2cd06e6 | 428 | free (new_bloc); |
98b7fe02 JB |
429 | |
430 | return 0; | |
431 | } | |
dcfdbac7 | 432 | |
91a211b5 | 433 | break_value = (char *) new_bloc->data + size; |
e429caa2 | 434 | |
dcfdbac7 JB |
435 | new_bloc->size = size; |
436 | new_bloc->next = NIL_BLOC; | |
8c7f1e35 | 437 | new_bloc->variable = (POINTER *) NIL; |
e429caa2 | 438 | new_bloc->new_data = 0; |
dcfdbac7 | 439 | |
abe9ff32 RS |
440 | /* Record in the heap that this space is in use. */ |
441 | heap = find_heap (new_bloc->data); | |
442 | heap->free = break_value; | |
443 | ||
47f13333 RS |
444 | /* Maintain the correspondence between heaps and blocs. */ |
445 | new_bloc->heap = heap; | |
446 | heap->last_bloc = new_bloc; | |
447 | if (heap->first_bloc == NIL_BLOC) | |
448 | heap->first_bloc = new_bloc; | |
449 | ||
abe9ff32 | 450 | /* Put this bloc on the doubly-linked list of blocs. */ |
dcfdbac7 JB |
451 | if (first_bloc) |
452 | { | |
453 | new_bloc->prev = last_bloc; | |
454 | last_bloc->next = new_bloc; | |
455 | last_bloc = new_bloc; | |
456 | } | |
457 | else | |
458 | { | |
459 | first_bloc = last_bloc = new_bloc; | |
460 | new_bloc->prev = NIL_BLOC; | |
461 | } | |
462 | ||
463 | return new_bloc; | |
464 | } | |
47f13333 | 465 | \f |
abe9ff32 RS |
466 | /* Calculate new locations of blocs in the list beginning with BLOC, |
467 | relocating it to start at ADDRESS, in heap HEAP. If enough space is | |
468 | not presently available in our reserve, call obtain for | |
177c0ea7 JB |
469 | more space. |
470 | ||
abe9ff32 RS |
471 | Store the new location of each bloc in its new_data field. |
472 | Do not touch the contents of blocs or break_value. */ | |
dcfdbac7 | 473 | |
e429caa2 KH |
474 | static int |
475 | relocate_blocs (bloc, heap, address) | |
476 | bloc_ptr bloc; | |
477 | heap_ptr heap; | |
478 | POINTER address; | |
479 | { | |
480 | register bloc_ptr b = bloc; | |
ad3bb3d2 | 481 | |
49f82b3d | 482 | /* No need to ever call this if arena is frozen, bug somewhere! */ |
177c0ea7 | 483 | if (r_alloc_freeze_level) |
49f82b3d RS |
484 | abort(); |
485 | ||
e429caa2 KH |
486 | while (b) |
487 | { | |
abe9ff32 RS |
488 | /* If bloc B won't fit within HEAP, |
489 | move to the next heap and try again. */ | |
91a211b5 | 490 | while (heap && (char *) address + b->size > (char *) heap->end) |
e429caa2 KH |
491 | { |
492 | heap = heap->next; | |
493 | if (heap == NIL_HEAP) | |
494 | break; | |
495 | address = heap->bloc_start; | |
496 | } | |
dcfdbac7 | 497 | |
abe9ff32 RS |
498 | /* If BLOC won't fit in any heap, |
499 | get enough new space to hold BLOC and all following blocs. */ | |
e429caa2 KH |
500 | if (heap == NIL_HEAP) |
501 | { | |
502 | register bloc_ptr tb = b; | |
503 | register SIZE s = 0; | |
504 | ||
abe9ff32 | 505 | /* Add up the size of all the following blocs. */ |
e429caa2 KH |
506 | while (tb != NIL_BLOC) |
507 | { | |
177c0ea7 | 508 | if (tb->variable) |
49f82b3d RS |
509 | s += tb->size; |
510 | ||
e429caa2 KH |
511 | tb = tb->next; |
512 | } | |
513 | ||
abe9ff32 RS |
514 | /* Get that space. */ |
515 | address = obtain (address, s); | |
516 | if (address == 0) | |
e429caa2 KH |
517 | return 0; |
518 | ||
519 | heap = last_heap; | |
520 | } | |
521 | ||
abe9ff32 RS |
522 | /* Record the new address of this bloc |
523 | and update where the next bloc can start. */ | |
e429caa2 | 524 | b->new_data = address; |
177c0ea7 | 525 | if (b->variable) |
91a211b5 | 526 | address = (char *) address + b->size; |
e429caa2 KH |
527 | b = b->next; |
528 | } | |
529 | ||
530 | return 1; | |
531 | } | |
532 | ||
47f13333 RS |
533 | /* Reorder the bloc BLOC to go before bloc BEFORE in the doubly linked list. |
534 | This is necessary if we put the memory of space of BLOC | |
535 | before that of BEFORE. */ | |
536 | ||
537 | static void | |
538 | reorder_bloc (bloc, before) | |
539 | bloc_ptr bloc, before; | |
540 | { | |
541 | bloc_ptr prev, next; | |
542 | ||
543 | /* Splice BLOC out from where it is. */ | |
544 | prev = bloc->prev; | |
545 | next = bloc->next; | |
546 | ||
547 | if (prev) | |
548 | prev->next = next; | |
549 | if (next) | |
550 | next->prev = prev; | |
551 | ||
552 | /* Splice it in before BEFORE. */ | |
553 | prev = before->prev; | |
abe9ff32 | 554 | |
47f13333 RS |
555 | if (prev) |
556 | prev->next = bloc; | |
557 | bloc->prev = prev; | |
558 | ||
559 | before->prev = bloc; | |
560 | bloc->next = before; | |
561 | } | |
562 | \f | |
563 | /* Update the records of which heaps contain which blocs, starting | |
564 | with heap HEAP and bloc BLOC. */ | |
565 | ||
566 | static void | |
567 | update_heap_bloc_correspondence (bloc, heap) | |
abe9ff32 RS |
568 | bloc_ptr bloc; |
569 | heap_ptr heap; | |
570 | { | |
571 | register bloc_ptr b; | |
572 | ||
47f13333 RS |
573 | /* Initialize HEAP's status to reflect blocs before BLOC. */ |
574 | if (bloc != NIL_BLOC && bloc->prev != NIL_BLOC && bloc->prev->heap == heap) | |
575 | { | |
576 | /* The previous bloc is in HEAP. */ | |
577 | heap->last_bloc = bloc->prev; | |
91a211b5 | 578 | heap->free = (char *) bloc->prev->data + bloc->prev->size; |
47f13333 RS |
579 | } |
580 | else | |
581 | { | |
582 | /* HEAP contains no blocs before BLOC. */ | |
583 | heap->first_bloc = NIL_BLOC; | |
584 | heap->last_bloc = NIL_BLOC; | |
585 | heap->free = heap->bloc_start; | |
586 | } | |
587 | ||
abe9ff32 RS |
588 | /* Advance through blocs one by one. */ |
589 | for (b = bloc; b != NIL_BLOC; b = b->next) | |
590 | { | |
47f13333 RS |
591 | /* Advance through heaps, marking them empty, |
592 | till we get to the one that B is in. */ | |
abe9ff32 RS |
593 | while (heap) |
594 | { | |
595 | if (heap->bloc_start <= b->data && b->data <= heap->end) | |
596 | break; | |
597 | heap = heap->next; | |
47f13333 RS |
598 | /* We know HEAP is not null now, |
599 | because there has to be space for bloc B. */ | |
600 | heap->first_bloc = NIL_BLOC; | |
601 | heap->last_bloc = NIL_BLOC; | |
abe9ff32 RS |
602 | heap->free = heap->bloc_start; |
603 | } | |
47f13333 RS |
604 | |
605 | /* Update HEAP's status for bloc B. */ | |
91a211b5 | 606 | heap->free = (char *) b->data + b->size; |
47f13333 RS |
607 | heap->last_bloc = b; |
608 | if (heap->first_bloc == NIL_BLOC) | |
609 | heap->first_bloc = b; | |
610 | ||
611 | /* Record that B is in HEAP. */ | |
612 | b->heap = heap; | |
abe9ff32 RS |
613 | } |
614 | ||
615 | /* If there are any remaining heaps and no blocs left, | |
47f13333 | 616 | mark those heaps as empty. */ |
abe9ff32 RS |
617 | heap = heap->next; |
618 | while (heap) | |
619 | { | |
47f13333 RS |
620 | heap->first_bloc = NIL_BLOC; |
621 | heap->last_bloc = NIL_BLOC; | |
abe9ff32 RS |
622 | heap->free = heap->bloc_start; |
623 | heap = heap->next; | |
624 | } | |
625 | } | |
47f13333 | 626 | \f |
abe9ff32 RS |
627 | /* Resize BLOC to SIZE bytes. This relocates the blocs |
628 | that come after BLOC in memory. */ | |
629 | ||
e429caa2 KH |
630 | static int |
631 | resize_bloc (bloc, size) | |
632 | bloc_ptr bloc; | |
633 | SIZE size; | |
dcfdbac7 | 634 | { |
e429caa2 KH |
635 | register bloc_ptr b; |
636 | heap_ptr heap; | |
637 | POINTER address; | |
638 | SIZE old_size; | |
639 | ||
49f82b3d | 640 | /* No need to ever call this if arena is frozen, bug somewhere! */ |
177c0ea7 | 641 | if (r_alloc_freeze_level) |
49f82b3d RS |
642 | abort(); |
643 | ||
e429caa2 KH |
644 | if (bloc == NIL_BLOC || size == bloc->size) |
645 | return 1; | |
646 | ||
647 | for (heap = first_heap; heap != NIL_HEAP; heap = heap->next) | |
648 | { | |
649 | if (heap->bloc_start <= bloc->data && bloc->data <= heap->end) | |
650 | break; | |
651 | } | |
652 | ||
653 | if (heap == NIL_HEAP) | |
abe9ff32 | 654 | abort (); |
e429caa2 KH |
655 | |
656 | old_size = bloc->size; | |
657 | bloc->size = size; | |
658 | ||
abe9ff32 | 659 | /* Note that bloc could be moved into the previous heap. */ |
91a211b5 GM |
660 | address = (bloc->prev ? (char *) bloc->prev->data + bloc->prev->size |
661 | : (char *) first_heap->bloc_start); | |
e429caa2 KH |
662 | while (heap) |
663 | { | |
664 | if (heap->bloc_start <= address && address <= heap->end) | |
665 | break; | |
666 | heap = heap->prev; | |
667 | } | |
668 | ||
669 | if (! relocate_blocs (bloc, heap, address)) | |
670 | { | |
671 | bloc->size = old_size; | |
672 | return 0; | |
673 | } | |
674 | ||
675 | if (size > old_size) | |
676 | { | |
677 | for (b = last_bloc; b != bloc; b = b->prev) | |
678 | { | |
49f82b3d RS |
679 | if (!b->variable) |
680 | { | |
681 | b->size = 0; | |
682 | b->data = b->new_data; | |
177c0ea7 JB |
683 | } |
684 | else | |
49f82b3d RS |
685 | { |
686 | safe_bcopy (b->data, b->new_data, b->size); | |
687 | *b->variable = b->data = b->new_data; | |
688 | } | |
689 | } | |
690 | if (!bloc->variable) | |
691 | { | |
692 | bloc->size = 0; | |
693 | bloc->data = bloc->new_data; | |
694 | } | |
695 | else | |
696 | { | |
697 | safe_bcopy (bloc->data, bloc->new_data, old_size); | |
91a211b5 | 698 | bzero ((char *) bloc->new_data + old_size, size - old_size); |
49f82b3d | 699 | *bloc->variable = bloc->data = bloc->new_data; |
e429caa2 | 700 | } |
e429caa2 KH |
701 | } |
702 | else | |
dcfdbac7 | 703 | { |
ad3bb3d2 JB |
704 | for (b = bloc; b != NIL_BLOC; b = b->next) |
705 | { | |
49f82b3d RS |
706 | if (!b->variable) |
707 | { | |
708 | b->size = 0; | |
709 | b->data = b->new_data; | |
177c0ea7 JB |
710 | } |
711 | else | |
49f82b3d RS |
712 | { |
713 | safe_bcopy (b->data, b->new_data, b->size); | |
714 | *b->variable = b->data = b->new_data; | |
715 | } | |
ad3bb3d2 | 716 | } |
ad3bb3d2 | 717 | } |
dcfdbac7 | 718 | |
47f13333 | 719 | update_heap_bloc_correspondence (bloc, heap); |
abe9ff32 | 720 | |
91a211b5 GM |
721 | break_value = (last_bloc ? (char *) last_bloc->data + last_bloc->size |
722 | : (char *) first_heap->bloc_start); | |
e429caa2 KH |
723 | return 1; |
724 | } | |
47f13333 | 725 | \f |
abe9ff32 RS |
726 | /* Free BLOC from the chain of blocs, relocating any blocs above it. |
727 | This may return space to the system. */ | |
dcfdbac7 JB |
728 | |
729 | static void | |
730 | free_bloc (bloc) | |
731 | bloc_ptr bloc; | |
732 | { | |
47f13333 RS |
733 | heap_ptr heap = bloc->heap; |
734 | ||
49f82b3d RS |
735 | if (r_alloc_freeze_level) |
736 | { | |
737 | bloc->variable = (POINTER *) NIL; | |
738 | return; | |
739 | } | |
177c0ea7 | 740 | |
e429caa2 KH |
741 | resize_bloc (bloc, 0); |
742 | ||
dcfdbac7 JB |
743 | if (bloc == first_bloc && bloc == last_bloc) |
744 | { | |
745 | first_bloc = last_bloc = NIL_BLOC; | |
746 | } | |
747 | else if (bloc == last_bloc) | |
748 | { | |
749 | last_bloc = bloc->prev; | |
750 | last_bloc->next = NIL_BLOC; | |
751 | } | |
752 | else if (bloc == first_bloc) | |
753 | { | |
754 | first_bloc = bloc->next; | |
755 | first_bloc->prev = NIL_BLOC; | |
dcfdbac7 JB |
756 | } |
757 | else | |
758 | { | |
759 | bloc->next->prev = bloc->prev; | |
760 | bloc->prev->next = bloc->next; | |
dcfdbac7 JB |
761 | } |
762 | ||
47f13333 RS |
763 | /* Update the records of which blocs are in HEAP. */ |
764 | if (heap->first_bloc == bloc) | |
765 | { | |
d5179acc | 766 | if (bloc->next != 0 && bloc->next->heap == heap) |
47f13333 RS |
767 | heap->first_bloc = bloc->next; |
768 | else | |
769 | heap->first_bloc = heap->last_bloc = NIL_BLOC; | |
770 | } | |
771 | if (heap->last_bloc == bloc) | |
772 | { | |
d5179acc | 773 | if (bloc->prev != 0 && bloc->prev->heap == heap) |
47f13333 RS |
774 | heap->last_bloc = bloc->prev; |
775 | else | |
776 | heap->first_bloc = heap->last_bloc = NIL_BLOC; | |
777 | } | |
778 | ||
e429caa2 | 779 | relinquish (); |
dcfdbac7 JB |
780 | free (bloc); |
781 | } | |
782 | \f | |
956ace37 JB |
783 | /* Interface routines. */ |
784 | ||
98b7fe02 | 785 | /* Obtain SIZE bytes of storage from the free pool, or the system, as |
2c46d29f | 786 | necessary. If relocatable blocs are in use, this means relocating |
98b7fe02 JB |
787 | them. This function gets plugged into the GNU malloc's __morecore |
788 | hook. | |
789 | ||
7516b7d5 RS |
790 | We provide hysteresis, never relocating by less than extra_bytes. |
791 | ||
98b7fe02 JB |
792 | If we're out of memory, we should return zero, to imitate the other |
793 | __morecore hook values - in particular, __default_morecore in the | |
794 | GNU malloc package. */ | |
dcfdbac7 | 795 | |
177c0ea7 | 796 | POINTER |
dcfdbac7 JB |
797 | r_alloc_sbrk (size) |
798 | long size; | |
799 | { | |
e429caa2 KH |
800 | register bloc_ptr b; |
801 | POINTER address; | |
dcfdbac7 | 802 | |
44d3dec0 RS |
803 | if (! r_alloc_initialized) |
804 | r_alloc_init (); | |
805 | ||
dcfdbac7 | 806 | if (! use_relocatable_buffers) |
bbc60227 | 807 | return (*real_morecore) (size); |
dcfdbac7 | 808 | |
e429caa2 KH |
809 | if (size == 0) |
810 | return virtual_break_value; | |
7516b7d5 | 811 | |
e429caa2 | 812 | if (size > 0) |
dcfdbac7 | 813 | { |
abe9ff32 RS |
814 | /* Allocate a page-aligned space. GNU malloc would reclaim an |
815 | extra space if we passed an unaligned one. But we could | |
8e6208c5 | 816 | not always find a space which is contiguous to the previous. */ |
e429caa2 KH |
817 | POINTER new_bloc_start; |
818 | heap_ptr h = first_heap; | |
abe9ff32 | 819 | SIZE get = ROUNDUP (size); |
7516b7d5 | 820 | |
abe9ff32 | 821 | address = (POINTER) ROUNDUP (virtual_break_value); |
e429caa2 | 822 | |
abe9ff32 RS |
823 | /* Search the list upward for a heap which is large enough. */ |
824 | while ((char *) h->end < (char *) MEM_ROUNDUP ((char *)address + get)) | |
e429caa2 KH |
825 | { |
826 | h = h->next; | |
827 | if (h == NIL_HEAP) | |
828 | break; | |
abe9ff32 | 829 | address = (POINTER) ROUNDUP (h->start); |
e429caa2 KH |
830 | } |
831 | ||
abe9ff32 | 832 | /* If not found, obtain more space. */ |
e429caa2 KH |
833 | if (h == NIL_HEAP) |
834 | { | |
835 | get += extra_bytes + page_size; | |
836 | ||
49f82b3d | 837 | if (! obtain (address, get)) |
e429caa2 | 838 | return 0; |
98b7fe02 | 839 | |
e429caa2 | 840 | if (first_heap == last_heap) |
abe9ff32 | 841 | address = (POINTER) ROUNDUP (virtual_break_value); |
e429caa2 | 842 | else |
abe9ff32 | 843 | address = (POINTER) ROUNDUP (last_heap->start); |
e429caa2 KH |
844 | h = last_heap; |
845 | } | |
846 | ||
abe9ff32 | 847 | new_bloc_start = (POINTER) MEM_ROUNDUP ((char *)address + get); |
e429caa2 KH |
848 | |
849 | if (first_heap->bloc_start < new_bloc_start) | |
850 | { | |
49f82b3d | 851 | /* This is no clean solution - no idea how to do it better. */ |
177c0ea7 | 852 | if (r_alloc_freeze_level) |
49f82b3d RS |
853 | return NIL; |
854 | ||
855 | /* There is a bug here: if the above obtain call succeeded, but the | |
856 | relocate_blocs call below does not succeed, we need to free | |
857 | the memory that we got with obtain. */ | |
858 | ||
abe9ff32 | 859 | /* Move all blocs upward. */ |
49f82b3d | 860 | if (! relocate_blocs (first_bloc, h, new_bloc_start)) |
e429caa2 KH |
861 | return 0; |
862 | ||
863 | /* Note that (POINTER)(h+1) <= new_bloc_start since | |
864 | get >= page_size, so the following does not destroy the heap | |
abe9ff32 | 865 | header. */ |
e429caa2 KH |
866 | for (b = last_bloc; b != NIL_BLOC; b = b->prev) |
867 | { | |
868 | safe_bcopy (b->data, b->new_data, b->size); | |
869 | *b->variable = b->data = b->new_data; | |
870 | } | |
871 | ||
872 | h->bloc_start = new_bloc_start; | |
abe9ff32 | 873 | |
47f13333 | 874 | update_heap_bloc_correspondence (first_bloc, h); |
e429caa2 | 875 | } |
e429caa2 KH |
876 | if (h != first_heap) |
877 | { | |
878 | /* Give up managing heaps below the one the new | |
abe9ff32 | 879 | virtual_break_value points to. */ |
e429caa2 KH |
880 | first_heap->prev = NIL_HEAP; |
881 | first_heap->next = h->next; | |
882 | first_heap->start = h->start; | |
883 | first_heap->end = h->end; | |
abe9ff32 | 884 | first_heap->free = h->free; |
47f13333 RS |
885 | first_heap->first_bloc = h->first_bloc; |
886 | first_heap->last_bloc = h->last_bloc; | |
e429caa2 KH |
887 | first_heap->bloc_start = h->bloc_start; |
888 | ||
889 | if (first_heap->next) | |
890 | first_heap->next->prev = first_heap; | |
891 | else | |
892 | last_heap = first_heap; | |
893 | } | |
894 | ||
895 | bzero (address, size); | |
dcfdbac7 | 896 | } |
e429caa2 | 897 | else /* size < 0 */ |
dcfdbac7 | 898 | { |
e429caa2 KH |
899 | SIZE excess = (char *)first_heap->bloc_start |
900 | - ((char *)virtual_break_value + size); | |
901 | ||
902 | address = virtual_break_value; | |
903 | ||
904 | if (r_alloc_freeze_level == 0 && excess > 2 * extra_bytes) | |
905 | { | |
906 | excess -= extra_bytes; | |
907 | first_heap->bloc_start | |
47f13333 | 908 | = (POINTER) MEM_ROUNDUP ((char *)first_heap->bloc_start - excess); |
e429caa2 | 909 | |
abe9ff32 | 910 | relocate_blocs (first_bloc, first_heap, first_heap->bloc_start); |
7516b7d5 | 911 | |
e429caa2 KH |
912 | for (b = first_bloc; b != NIL_BLOC; b = b->next) |
913 | { | |
914 | safe_bcopy (b->data, b->new_data, b->size); | |
915 | *b->variable = b->data = b->new_data; | |
916 | } | |
917 | } | |
918 | ||
919 | if ((char *)virtual_break_value + size < (char *)first_heap->start) | |
920 | { | |
921 | /* We found an additional space below the first heap */ | |
922 | first_heap->start = (POINTER) ((char *)virtual_break_value + size); | |
923 | } | |
dcfdbac7 JB |
924 | } |
925 | ||
e429caa2 | 926 | virtual_break_value = (POINTER) ((char *)address + size); |
47f13333 | 927 | break_value = (last_bloc |
91a211b5 GM |
928 | ? (char *) last_bloc->data + last_bloc->size |
929 | : (char *) first_heap->bloc_start); | |
e429caa2 | 930 | if (size < 0) |
abe9ff32 | 931 | relinquish (); |
7516b7d5 | 932 | |
e429caa2 | 933 | return address; |
dcfdbac7 JB |
934 | } |
935 | ||
0a58f946 | 936 | |
dcfdbac7 JB |
937 | /* Allocate a relocatable bloc of storage of size SIZE. A pointer to |
938 | the data is returned in *PTR. PTR is thus the address of some variable | |
98b7fe02 JB |
939 | which will use the data area. |
940 | ||
49f82b3d RS |
941 | The allocation of 0 bytes is valid. |
942 | In case r_alloc_freeze is set, a best fit of unused blocs could be done | |
943 | before allocating a new area. Not yet done. | |
944 | ||
98b7fe02 JB |
945 | If we can't allocate the necessary memory, set *PTR to zero, and |
946 | return zero. */ | |
dcfdbac7 JB |
947 | |
948 | POINTER | |
949 | r_alloc (ptr, size) | |
950 | POINTER *ptr; | |
951 | SIZE size; | |
952 | { | |
953 | register bloc_ptr new_bloc; | |
954 | ||
2c46d29f RS |
955 | if (! r_alloc_initialized) |
956 | r_alloc_init (); | |
957 | ||
abe9ff32 | 958 | new_bloc = get_bloc (MEM_ROUNDUP (size)); |
98b7fe02 JB |
959 | if (new_bloc) |
960 | { | |
961 | new_bloc->variable = ptr; | |
962 | *ptr = new_bloc->data; | |
963 | } | |
964 | else | |
965 | *ptr = 0; | |
dcfdbac7 JB |
966 | |
967 | return *ptr; | |
968 | } | |
969 | ||
2c46d29f RS |
970 | /* Free a bloc of relocatable storage whose data is pointed to by PTR. |
971 | Store 0 in *PTR to show there's no block allocated. */ | |
dcfdbac7 JB |
972 | |
973 | void | |
974 | r_alloc_free (ptr) | |
975 | register POINTER *ptr; | |
976 | { | |
977 | register bloc_ptr dead_bloc; | |
978 | ||
44d3dec0 RS |
979 | if (! r_alloc_initialized) |
980 | r_alloc_init (); | |
981 | ||
dcfdbac7 JB |
982 | dead_bloc = find_bloc (ptr); |
983 | if (dead_bloc == NIL_BLOC) | |
984 | abort (); | |
985 | ||
986 | free_bloc (dead_bloc); | |
2c46d29f | 987 | *ptr = 0; |
719b242f | 988 | |
d5179acc | 989 | #ifdef emacs |
719b242f | 990 | refill_memory_reserve (); |
d5179acc | 991 | #endif |
dcfdbac7 JB |
992 | } |
993 | ||
16a5c729 | 994 | /* Given a pointer at address PTR to relocatable data, resize it to SIZE. |
98b7fe02 JB |
995 | Do this by shifting all blocks above this one up in memory, unless |
996 | SIZE is less than or equal to the current bloc size, in which case | |
997 | do nothing. | |
dcfdbac7 | 998 | |
49f82b3d | 999 | In case r_alloc_freeze is set, a new bloc is allocated, and the |
8e6208c5 | 1000 | memory copied to it. Not very efficient. We could traverse the |
49f82b3d RS |
1001 | bloc_list for a best fit of free blocs first. |
1002 | ||
98b7fe02 JB |
1003 | Change *PTR to reflect the new bloc, and return this value. |
1004 | ||
1005 | If more memory cannot be allocated, then leave *PTR unchanged, and | |
1006 | return zero. */ | |
dcfdbac7 JB |
1007 | |
1008 | POINTER | |
1009 | r_re_alloc (ptr, size) | |
1010 | POINTER *ptr; | |
1011 | SIZE size; | |
1012 | { | |
16a5c729 | 1013 | register bloc_ptr bloc; |
dcfdbac7 | 1014 | |
44d3dec0 RS |
1015 | if (! r_alloc_initialized) |
1016 | r_alloc_init (); | |
1017 | ||
49f82b3d RS |
1018 | if (!*ptr) |
1019 | return r_alloc (ptr, size); | |
177c0ea7 | 1020 | if (!size) |
49f82b3d RS |
1021 | { |
1022 | r_alloc_free (ptr); | |
1023 | return r_alloc (ptr, 0); | |
1024 | } | |
1025 | ||
16a5c729 JB |
1026 | bloc = find_bloc (ptr); |
1027 | if (bloc == NIL_BLOC) | |
dcfdbac7 JB |
1028 | abort (); |
1029 | ||
177c0ea7 | 1030 | if (size < bloc->size) |
49f82b3d RS |
1031 | { |
1032 | /* Wouldn't it be useful to actually resize the bloc here? */ | |
1033 | /* I think so too, but not if it's too expensive... */ | |
177c0ea7 JB |
1034 | if ((bloc->size - MEM_ROUNDUP (size) >= page_size) |
1035 | && r_alloc_freeze_level == 0) | |
49f82b3d RS |
1036 | { |
1037 | resize_bloc (bloc, MEM_ROUNDUP (size)); | |
1038 | /* Never mind if this fails, just do nothing... */ | |
1039 | /* It *should* be infallible! */ | |
1040 | } | |
1041 | } | |
1042 | else if (size > bloc->size) | |
1043 | { | |
1044 | if (r_alloc_freeze_level) | |
1045 | { | |
1046 | bloc_ptr new_bloc; | |
1047 | new_bloc = get_bloc (MEM_ROUNDUP (size)); | |
1048 | if (new_bloc) | |
1049 | { | |
1050 | new_bloc->variable = ptr; | |
1051 | *ptr = new_bloc->data; | |
1052 | bloc->variable = (POINTER *) NIL; | |
1053 | } | |
1054 | else | |
1055 | return NIL; | |
1056 | } | |
177c0ea7 | 1057 | else |
49f82b3d RS |
1058 | { |
1059 | if (! resize_bloc (bloc, MEM_ROUNDUP (size))) | |
1060 | return NIL; | |
1061 | } | |
1062 | } | |
dcfdbac7 JB |
1063 | return *ptr; |
1064 | } | |
81bd58e8 KH |
1065 | |
1066 | /* Disable relocations, after making room for at least SIZE bytes | |
1067 | of non-relocatable heap if possible. The relocatable blocs are | |
1068 | guaranteed to hold still until thawed, even if this means that | |
1069 | malloc must return a null pointer. */ | |
abe9ff32 | 1070 | |
81bd58e8 KH |
1071 | void |
1072 | r_alloc_freeze (size) | |
1073 | long size; | |
1074 | { | |
44d3dec0 RS |
1075 | if (! r_alloc_initialized) |
1076 | r_alloc_init (); | |
1077 | ||
81bd58e8 KH |
1078 | /* If already frozen, we can't make any more room, so don't try. */ |
1079 | if (r_alloc_freeze_level > 0) | |
1080 | size = 0; | |
1081 | /* If we can't get the amount requested, half is better than nothing. */ | |
1082 | while (size > 0 && r_alloc_sbrk (size) == 0) | |
1083 | size /= 2; | |
1084 | ++r_alloc_freeze_level; | |
1085 | if (size > 0) | |
1086 | r_alloc_sbrk (-size); | |
1087 | } | |
1088 | ||
1089 | void | |
1090 | r_alloc_thaw () | |
1091 | { | |
49f82b3d | 1092 | |
177c0ea7 | 1093 | if (! r_alloc_initialized) |
49f82b3d RS |
1094 | r_alloc_init (); |
1095 | ||
81bd58e8 KH |
1096 | if (--r_alloc_freeze_level < 0) |
1097 | abort (); | |
49f82b3d | 1098 | |
177c0ea7 JB |
1099 | /* This frees all unused blocs. It is not too inefficient, as the resize |
1100 | and bcopy is done only once. Afterwards, all unreferenced blocs are | |
49f82b3d | 1101 | already shrunk to zero size. */ |
177c0ea7 | 1102 | if (!r_alloc_freeze_level) |
49f82b3d RS |
1103 | { |
1104 | bloc_ptr *b = &first_bloc; | |
177c0ea7 JB |
1105 | while (*b) |
1106 | if (!(*b)->variable) | |
1107 | free_bloc (*b); | |
1108 | else | |
49f82b3d RS |
1109 | b = &(*b)->next; |
1110 | } | |
81bd58e8 | 1111 | } |
49f82b3d | 1112 | |
dec41418 RS |
1113 | |
1114 | #if defined (emacs) && defined (DOUG_LEA_MALLOC) | |
1115 | ||
1116 | /* Reinitialize the morecore hook variables after restarting a dumped | |
1117 | Emacs. This is needed when using Doug Lea's malloc from GNU libc. */ | |
1118 | void | |
1119 | r_alloc_reinit () | |
1120 | { | |
1121 | /* Only do this if the hook has been reset, so that we don't get an | |
1122 | infinite loop, in case Emacs was linked statically. */ | |
1123 | if (__morecore != r_alloc_sbrk) | |
1124 | { | |
1125 | real_morecore = __morecore; | |
1126 | __morecore = r_alloc_sbrk; | |
1127 | } | |
1128 | } | |
0a58f946 GM |
1129 | |
1130 | #endif /* emacs && DOUG_LEA_MALLOC */ | |
dec41418 | 1131 | |
e429caa2 | 1132 | #ifdef DEBUG |
0a58f946 | 1133 | |
e429caa2 KH |
1134 | #include <assert.h> |
1135 | ||
44d3dec0 | 1136 | void |
e429caa2 KH |
1137 | r_alloc_check () |
1138 | { | |
6d16dd06 RS |
1139 | int found = 0; |
1140 | heap_ptr h, ph = 0; | |
1141 | bloc_ptr b, pb = 0; | |
1142 | ||
1143 | if (!r_alloc_initialized) | |
1144 | return; | |
1145 | ||
1146 | assert (first_heap); | |
1147 | assert (last_heap->end <= (POINTER) sbrk (0)); | |
1148 | assert ((POINTER) first_heap < first_heap->start); | |
1149 | assert (first_heap->start <= virtual_break_value); | |
1150 | assert (virtual_break_value <= first_heap->end); | |
1151 | ||
1152 | for (h = first_heap; h; h = h->next) | |
1153 | { | |
1154 | assert (h->prev == ph); | |
1155 | assert ((POINTER) ROUNDUP (h->end) == h->end); | |
40f3f04b RS |
1156 | #if 0 /* ??? The code in ralloc.c does not really try to ensure |
1157 | the heap start has any sort of alignment. | |
1158 | Perhaps it should. */ | |
6d16dd06 | 1159 | assert ((POINTER) MEM_ROUNDUP (h->start) == h->start); |
40f3f04b | 1160 | #endif |
6d16dd06 RS |
1161 | assert ((POINTER) MEM_ROUNDUP (h->bloc_start) == h->bloc_start); |
1162 | assert (h->start <= h->bloc_start && h->bloc_start <= h->end); | |
1163 | ||
1164 | if (ph) | |
1165 | { | |
1166 | assert (ph->end < h->start); | |
1167 | assert (h->start <= (POINTER)h && (POINTER)(h+1) <= h->bloc_start); | |
1168 | } | |
1169 | ||
1170 | if (h->bloc_start <= break_value && break_value <= h->end) | |
1171 | found = 1; | |
1172 | ||
1173 | ph = h; | |
1174 | } | |
1175 | ||
1176 | assert (found); | |
1177 | assert (last_heap == ph); | |
1178 | ||
1179 | for (b = first_bloc; b; b = b->next) | |
1180 | { | |
1181 | assert (b->prev == pb); | |
1182 | assert ((POINTER) MEM_ROUNDUP (b->data) == b->data); | |
1183 | assert ((SIZE) MEM_ROUNDUP (b->size) == b->size); | |
1184 | ||
1185 | ph = 0; | |
1186 | for (h = first_heap; h; h = h->next) | |
1187 | { | |
1188 | if (h->bloc_start <= b->data && b->data + b->size <= h->end) | |
1189 | break; | |
1190 | ph = h; | |
1191 | } | |
1192 | ||
1193 | assert (h); | |
1194 | ||
1195 | if (pb && pb->data + pb->size != b->data) | |
1196 | { | |
1197 | assert (ph && b->data == h->bloc_start); | |
1198 | while (ph) | |
1199 | { | |
1200 | if (ph->bloc_start <= pb->data | |
1201 | && pb->data + pb->size <= ph->end) | |
1202 | { | |
1203 | assert (pb->data + pb->size + b->size > ph->end); | |
1204 | break; | |
1205 | } | |
1206 | else | |
1207 | { | |
1208 | assert (ph->bloc_start + b->size > ph->end); | |
1209 | } | |
1210 | ph = ph->prev; | |
1211 | } | |
1212 | } | |
1213 | pb = b; | |
1214 | } | |
1215 | ||
1216 | assert (last_bloc == pb); | |
1217 | ||
1218 | if (last_bloc) | |
1219 | assert (last_bloc->data + last_bloc->size == break_value); | |
1220 | else | |
1221 | assert (first_heap->bloc_start == break_value); | |
e429caa2 | 1222 | } |
0a58f946 | 1223 | |
e429caa2 | 1224 | #endif /* DEBUG */ |
0a58f946 | 1225 | |
0a58f946 GM |
1226 | |
1227 | \f | |
1228 | /*********************************************************************** | |
1229 | Initialization | |
1230 | ***********************************************************************/ | |
1231 | ||
0a58f946 GM |
1232 | /* Initialize various things for memory allocation. */ |
1233 | ||
1234 | static void | |
1235 | r_alloc_init () | |
1236 | { | |
1237 | if (r_alloc_initialized) | |
1238 | return; | |
0a58f946 | 1239 | r_alloc_initialized = 1; |
177c0ea7 | 1240 | |
a2c23c92 DL |
1241 | page_size = PAGE; |
1242 | #ifndef SYSTEM_MALLOC | |
0a58f946 GM |
1243 | real_morecore = __morecore; |
1244 | __morecore = r_alloc_sbrk; | |
1245 | ||
1246 | first_heap = last_heap = &heap_base; | |
1247 | first_heap->next = first_heap->prev = NIL_HEAP; | |
1248 | first_heap->start = first_heap->bloc_start | |
1249 | = virtual_break_value = break_value = (*real_morecore) (0); | |
1250 | if (break_value == NIL) | |
1251 | abort (); | |
1252 | ||
0a58f946 | 1253 | extra_bytes = ROUNDUP (50000); |
a2c23c92 | 1254 | #endif |
0a58f946 GM |
1255 | |
1256 | #ifdef DOUG_LEA_MALLOC | |
1673df2e JD |
1257 | BLOCK_INPUT; |
1258 | mallopt (M_TOP_PAD, 64 * 4096); | |
1259 | UNBLOCK_INPUT; | |
0a58f946 | 1260 | #else |
a2c23c92 | 1261 | #ifndef SYSTEM_MALLOC |
0a58f946 GM |
1262 | /* Give GNU malloc's morecore some hysteresis |
1263 | so that we move all the relocatable blocks much less often. */ | |
1264 | __malloc_extra_blocks = 64; | |
1265 | #endif | |
a2c23c92 | 1266 | #endif |
0a58f946 | 1267 | |
5ad25b24 | 1268 | #ifndef SYSTEM_MALLOC |
0a58f946 GM |
1269 | first_heap->end = (POINTER) ROUNDUP (first_heap->start); |
1270 | ||
1271 | /* The extra call to real_morecore guarantees that the end of the | |
1272 | address space is a multiple of page_size, even if page_size is | |
1273 | not really the page size of the system running the binary in | |
1274 | which page_size is stored. This allows a binary to be built on a | |
1275 | system with one page size and run on a system with a smaller page | |
1276 | size. */ | |
91a211b5 | 1277 | (*real_morecore) ((char *) first_heap->end - (char *) first_heap->start); |
0a58f946 GM |
1278 | |
1279 | /* Clear the rest of the last page; this memory is in our address space | |
1280 | even though it is after the sbrk value. */ | |
1281 | /* Doubly true, with the additional call that explicitly adds the | |
1282 | rest of that page to the address space. */ | |
91a211b5 GM |
1283 | bzero (first_heap->start, |
1284 | (char *) first_heap->end - (char *) first_heap->start); | |
0a58f946 | 1285 | virtual_break_value = break_value = first_heap->bloc_start = first_heap->end; |
a2c23c92 | 1286 | #endif |
177c0ea7 | 1287 | |
0a58f946 GM |
1288 | use_relocatable_buffers = 1; |
1289 | } | |
ab5796a9 MB |
1290 | |
1291 | /* arch-tag: 6a524a15-faff-44c8-95d4-a5da6f55110f | |
1292 | (do not change this comment) */ |