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[bpt/emacs.git] / src / alloc.c
1 /* Storage allocation and gc for GNU Emacs Lisp interpreter.
2 Copyright (C) 1985, 1986, 1988, 1993, 1994, 1995, 1997, 1998, 1999,
3 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4
5 This file is part of GNU Emacs.
6
7 GNU Emacs is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
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
18 along with GNU Emacs; see the file COPYING. If not, write to
19 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 Boston, MA 02110-1301, USA. */
21
22 #include <config.h>
23 #include <stdio.h>
24 #include <limits.h> /* For CHAR_BIT. */
25
26 #ifdef ALLOC_DEBUG
27 #undef INLINE
28 #endif
29
30 /* Note that this declares bzero on OSF/1. How dumb. */
31
32 #include <signal.h>
33
34 #ifdef HAVE_GTK_AND_PTHREAD
35 #include <pthread.h>
36 #endif
37
38 /* This file is part of the core Lisp implementation, and thus must
39 deal with the real data structures. If the Lisp implementation is
40 replaced, this file likely will not be used. */
41
42 #undef HIDE_LISP_IMPLEMENTATION
43 #include "lisp.h"
44 #include "process.h"
45 #include "intervals.h"
46 #include "puresize.h"
47 #include "buffer.h"
48 #include "window.h"
49 #include "keyboard.h"
50 #include "frame.h"
51 #include "blockinput.h"
52 #include "charset.h"
53 #include "syssignal.h"
54 #include <setjmp.h>
55
56 /* GC_MALLOC_CHECK defined means perform validity checks of malloc'd
57 memory. Can do this only if using gmalloc.c. */
58
59 #if defined SYSTEM_MALLOC || defined DOUG_LEA_MALLOC
60 #undef GC_MALLOC_CHECK
61 #endif
62
63 #ifdef HAVE_UNISTD_H
64 #include <unistd.h>
65 #else
66 extern POINTER_TYPE *sbrk ();
67 #endif
68
69 #ifdef HAVE_FCNTL_H
70 #define INCLUDED_FCNTL
71 #include <fcntl.h>
72 #endif
73 #ifndef O_WRONLY
74 #define O_WRONLY 1
75 #endif
76
77 #ifdef DOUG_LEA_MALLOC
78
79 #include <malloc.h>
80 /* malloc.h #defines this as size_t, at least in glibc2. */
81 #ifndef __malloc_size_t
82 #define __malloc_size_t int
83 #endif
84
85 /* Specify maximum number of areas to mmap. It would be nice to use a
86 value that explicitly means "no limit". */
87
88 #define MMAP_MAX_AREAS 100000000
89
90 #else /* not DOUG_LEA_MALLOC */
91
92 /* The following come from gmalloc.c. */
93
94 #define __malloc_size_t size_t
95 extern __malloc_size_t _bytes_used;
96 extern __malloc_size_t __malloc_extra_blocks;
97
98 #endif /* not DOUG_LEA_MALLOC */
99
100 #if ! defined (SYSTEM_MALLOC) && defined (HAVE_GTK_AND_PTHREAD)
101
102 /* When GTK uses the file chooser dialog, different backends can be loaded
103 dynamically. One such a backend is the Gnome VFS backend that gets loaded
104 if you run Gnome. That backend creates several threads and also allocates
105 memory with malloc.
106
107 If Emacs sets malloc hooks (! SYSTEM_MALLOC) and the emacs_blocked_*
108 functions below are called from malloc, there is a chance that one
109 of these threads preempts the Emacs main thread and the hook variables
110 end up in an inconsistent state. So we have a mutex to prevent that (note
111 that the backend handles concurrent access to malloc within its own threads
112 but Emacs code running in the main thread is not included in that control).
113
114 When UNBLOCK_INPUT is called, reinvoke_input_signal may be called. If this
115 happens in one of the backend threads we will have two threads that tries
116 to run Emacs code at once, and the code is not prepared for that.
117 To prevent that, we only call BLOCK/UNBLOCK from the main thread. */
118
119 static pthread_mutex_t alloc_mutex;
120
121 #define BLOCK_INPUT_ALLOC \
122 do \
123 { \
124 pthread_mutex_lock (&alloc_mutex); \
125 if (pthread_self () == main_thread) \
126 BLOCK_INPUT; \
127 } \
128 while (0)
129 #define UNBLOCK_INPUT_ALLOC \
130 do \
131 { \
132 if (pthread_self () == main_thread) \
133 UNBLOCK_INPUT; \
134 pthread_mutex_unlock (&alloc_mutex); \
135 } \
136 while (0)
137
138 #else /* SYSTEM_MALLOC || not HAVE_GTK_AND_PTHREAD */
139
140 #define BLOCK_INPUT_ALLOC BLOCK_INPUT
141 #define UNBLOCK_INPUT_ALLOC UNBLOCK_INPUT
142
143 #endif /* SYSTEM_MALLOC || not HAVE_GTK_AND_PTHREAD */
144
145 /* Value of _bytes_used, when spare_memory was freed. */
146
147 static __malloc_size_t bytes_used_when_full;
148
149 static __malloc_size_t bytes_used_when_reconsidered;
150
151 /* Mark, unmark, query mark bit of a Lisp string. S must be a pointer
152 to a struct Lisp_String. */
153
154 #define MARK_STRING(S) ((S)->size |= ARRAY_MARK_FLAG)
155 #define UNMARK_STRING(S) ((S)->size &= ~ARRAY_MARK_FLAG)
156 #define STRING_MARKED_P(S) (((S)->size & ARRAY_MARK_FLAG) != 0)
157
158 #define VECTOR_MARK(V) ((V)->size |= ARRAY_MARK_FLAG)
159 #define VECTOR_UNMARK(V) ((V)->size &= ~ARRAY_MARK_FLAG)
160 #define VECTOR_MARKED_P(V) (((V)->size & ARRAY_MARK_FLAG) != 0)
161
162 /* Value is the number of bytes/chars of S, a pointer to a struct
163 Lisp_String. This must be used instead of STRING_BYTES (S) or
164 S->size during GC, because S->size contains the mark bit for
165 strings. */
166
167 #define GC_STRING_BYTES(S) (STRING_BYTES (S))
168 #define GC_STRING_CHARS(S) ((S)->size & ~ARRAY_MARK_FLAG)
169
170 /* Number of bytes of consing done since the last gc. */
171
172 int consing_since_gc;
173
174 /* Count the amount of consing of various sorts of space. */
175
176 EMACS_INT cons_cells_consed;
177 EMACS_INT floats_consed;
178 EMACS_INT vector_cells_consed;
179 EMACS_INT symbols_consed;
180 EMACS_INT string_chars_consed;
181 EMACS_INT misc_objects_consed;
182 EMACS_INT intervals_consed;
183 EMACS_INT strings_consed;
184
185 /* Minimum number of bytes of consing since GC before next GC. */
186
187 EMACS_INT gc_cons_threshold;
188
189 /* Similar minimum, computed from Vgc_cons_percentage. */
190
191 EMACS_INT gc_relative_threshold;
192
193 static Lisp_Object Vgc_cons_percentage;
194
195 /* Minimum number of bytes of consing since GC before next GC,
196 when memory is full. */
197
198 EMACS_INT memory_full_cons_threshold;
199
200 /* Nonzero during GC. */
201
202 int gc_in_progress;
203
204 /* Nonzero means abort if try to GC.
205 This is for code which is written on the assumption that
206 no GC will happen, so as to verify that assumption. */
207
208 int abort_on_gc;
209
210 /* Nonzero means display messages at beginning and end of GC. */
211
212 int garbage_collection_messages;
213
214 #ifndef VIRT_ADDR_VARIES
215 extern
216 #endif /* VIRT_ADDR_VARIES */
217 int malloc_sbrk_used;
218
219 #ifndef VIRT_ADDR_VARIES
220 extern
221 #endif /* VIRT_ADDR_VARIES */
222 int malloc_sbrk_unused;
223
224 /* Number of live and free conses etc. */
225
226 static int total_conses, total_markers, total_symbols, total_vector_size;
227 static int total_free_conses, total_free_markers, total_free_symbols;
228 static int total_free_floats, total_floats;
229
230 /* Points to memory space allocated as "spare", to be freed if we run
231 out of memory. We keep one large block, four cons-blocks, and
232 two string blocks. */
233
234 char *spare_memory[7];
235
236 /* Amount of spare memory to keep in large reserve block. */
237
238 #define SPARE_MEMORY (1 << 14)
239
240 /* Number of extra blocks malloc should get when it needs more core. */
241
242 static int malloc_hysteresis;
243
244 /* Non-nil means defun should do purecopy on the function definition. */
245
246 Lisp_Object Vpurify_flag;
247
248 /* Non-nil means we are handling a memory-full error. */
249
250 Lisp_Object Vmemory_full;
251
252 #ifndef HAVE_SHM
253
254 /* Initialize it to a nonzero value to force it into data space
255 (rather than bss space). That way unexec will remap it into text
256 space (pure), on some systems. We have not implemented the
257 remapping on more recent systems because this is less important
258 nowadays than in the days of small memories and timesharing. */
259
260 EMACS_INT pure[PURESIZE / sizeof (EMACS_INT)] = {1,};
261 #define PUREBEG (char *) pure
262
263 #else /* HAVE_SHM */
264
265 #define pure PURE_SEG_BITS /* Use shared memory segment */
266 #define PUREBEG (char *)PURE_SEG_BITS
267
268 #endif /* HAVE_SHM */
269
270 /* Pointer to the pure area, and its size. */
271
272 static char *purebeg;
273 static size_t pure_size;
274
275 /* Number of bytes of pure storage used before pure storage overflowed.
276 If this is non-zero, this implies that an overflow occurred. */
277
278 static size_t pure_bytes_used_before_overflow;
279
280 /* Value is non-zero if P points into pure space. */
281
282 #define PURE_POINTER_P(P) \
283 (((PNTR_COMPARISON_TYPE) (P) \
284 < (PNTR_COMPARISON_TYPE) ((char *) purebeg + pure_size)) \
285 && ((PNTR_COMPARISON_TYPE) (P) \
286 >= (PNTR_COMPARISON_TYPE) purebeg))
287
288 /* Index in pure at which next pure object will be allocated.. */
289
290 EMACS_INT pure_bytes_used;
291
292 /* If nonzero, this is a warning delivered by malloc and not yet
293 displayed. */
294
295 char *pending_malloc_warning;
296
297 /* Pre-computed signal argument for use when memory is exhausted. */
298
299 Lisp_Object Vmemory_signal_data;
300
301 /* Maximum amount of C stack to save when a GC happens. */
302
303 #ifndef MAX_SAVE_STACK
304 #define MAX_SAVE_STACK 16000
305 #endif
306
307 /* Buffer in which we save a copy of the C stack at each GC. */
308
309 char *stack_copy;
310 int stack_copy_size;
311
312 /* Non-zero means ignore malloc warnings. Set during initialization.
313 Currently not used. */
314
315 int ignore_warnings;
316
317 Lisp_Object Qgc_cons_threshold, Qchar_table_extra_slots;
318
319 /* Hook run after GC has finished. */
320
321 Lisp_Object Vpost_gc_hook, Qpost_gc_hook;
322
323 Lisp_Object Vgc_elapsed; /* accumulated elapsed time in GC */
324 EMACS_INT gcs_done; /* accumulated GCs */
325
326 static void mark_buffer P_ ((Lisp_Object));
327 extern void mark_kboards P_ ((void));
328 extern void mark_backtrace P_ ((void));
329 static void gc_sweep P_ ((void));
330 static void mark_glyph_matrix P_ ((struct glyph_matrix *));
331 static void mark_face_cache P_ ((struct face_cache *));
332
333 #ifdef HAVE_WINDOW_SYSTEM
334 extern void mark_fringe_data P_ ((void));
335 static void mark_image P_ ((struct image *));
336 static void mark_image_cache P_ ((struct frame *));
337 #endif /* HAVE_WINDOW_SYSTEM */
338
339 static struct Lisp_String *allocate_string P_ ((void));
340 static void compact_small_strings P_ ((void));
341 static void free_large_strings P_ ((void));
342 static void sweep_strings P_ ((void));
343
344 extern int message_enable_multibyte;
345
346 /* When scanning the C stack for live Lisp objects, Emacs keeps track
347 of what memory allocated via lisp_malloc is intended for what
348 purpose. This enumeration specifies the type of memory. */
349
350 enum mem_type
351 {
352 MEM_TYPE_NON_LISP,
353 MEM_TYPE_BUFFER,
354 MEM_TYPE_CONS,
355 MEM_TYPE_STRING,
356 MEM_TYPE_MISC,
357 MEM_TYPE_SYMBOL,
358 MEM_TYPE_FLOAT,
359 /* Keep the following vector-like types together, with
360 MEM_TYPE_WINDOW being the last, and MEM_TYPE_VECTOR the
361 first. Or change the code of live_vector_p, for instance. */
362 MEM_TYPE_VECTOR,
363 MEM_TYPE_PROCESS,
364 MEM_TYPE_HASH_TABLE,
365 MEM_TYPE_FRAME,
366 MEM_TYPE_WINDOW
367 };
368
369 static POINTER_TYPE *lisp_align_malloc P_ ((size_t, enum mem_type));
370 static POINTER_TYPE *lisp_malloc P_ ((size_t, enum mem_type));
371 void refill_memory_reserve ();
372
373
374 #if GC_MARK_STACK || defined GC_MALLOC_CHECK
375
376 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
377 #include <stdio.h> /* For fprintf. */
378 #endif
379
380 /* A unique object in pure space used to make some Lisp objects
381 on free lists recognizable in O(1). */
382
383 Lisp_Object Vdead;
384
385 #ifdef GC_MALLOC_CHECK
386
387 enum mem_type allocated_mem_type;
388 int dont_register_blocks;
389
390 #endif /* GC_MALLOC_CHECK */
391
392 /* A node in the red-black tree describing allocated memory containing
393 Lisp data. Each such block is recorded with its start and end
394 address when it is allocated, and removed from the tree when it
395 is freed.
396
397 A red-black tree is a balanced binary tree with the following
398 properties:
399
400 1. Every node is either red or black.
401 2. Every leaf is black.
402 3. If a node is red, then both of its children are black.
403 4. Every simple path from a node to a descendant leaf contains
404 the same number of black nodes.
405 5. The root is always black.
406
407 When nodes are inserted into the tree, or deleted from the tree,
408 the tree is "fixed" so that these properties are always true.
409
410 A red-black tree with N internal nodes has height at most 2
411 log(N+1). Searches, insertions and deletions are done in O(log N).
412 Please see a text book about data structures for a detailed
413 description of red-black trees. Any book worth its salt should
414 describe them. */
415
416 struct mem_node
417 {
418 /* Children of this node. These pointers are never NULL. When there
419 is no child, the value is MEM_NIL, which points to a dummy node. */
420 struct mem_node *left, *right;
421
422 /* The parent of this node. In the root node, this is NULL. */
423 struct mem_node *parent;
424
425 /* Start and end of allocated region. */
426 void *start, *end;
427
428 /* Node color. */
429 enum {MEM_BLACK, MEM_RED} color;
430
431 /* Memory type. */
432 enum mem_type type;
433 };
434
435 /* Base address of stack. Set in main. */
436
437 Lisp_Object *stack_base;
438
439 /* Root of the tree describing allocated Lisp memory. */
440
441 static struct mem_node *mem_root;
442
443 /* Lowest and highest known address in the heap. */
444
445 static void *min_heap_address, *max_heap_address;
446
447 /* Sentinel node of the tree. */
448
449 static struct mem_node mem_z;
450 #define MEM_NIL &mem_z
451
452 static POINTER_TYPE *lisp_malloc P_ ((size_t, enum mem_type));
453 static struct Lisp_Vector *allocate_vectorlike P_ ((EMACS_INT, enum mem_type));
454 static void lisp_free P_ ((POINTER_TYPE *));
455 static void mark_stack P_ ((void));
456 static int live_vector_p P_ ((struct mem_node *, void *));
457 static int live_buffer_p P_ ((struct mem_node *, void *));
458 static int live_string_p P_ ((struct mem_node *, void *));
459 static int live_cons_p P_ ((struct mem_node *, void *));
460 static int live_symbol_p P_ ((struct mem_node *, void *));
461 static int live_float_p P_ ((struct mem_node *, void *));
462 static int live_misc_p P_ ((struct mem_node *, void *));
463 static void mark_maybe_object P_ ((Lisp_Object));
464 static void mark_memory P_ ((void *, void *));
465 static void mem_init P_ ((void));
466 static struct mem_node *mem_insert P_ ((void *, void *, enum mem_type));
467 static void mem_insert_fixup P_ ((struct mem_node *));
468 static void mem_rotate_left P_ ((struct mem_node *));
469 static void mem_rotate_right P_ ((struct mem_node *));
470 static void mem_delete P_ ((struct mem_node *));
471 static void mem_delete_fixup P_ ((struct mem_node *));
472 static INLINE struct mem_node *mem_find P_ ((void *));
473
474
475 #if GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS
476 static void check_gcpros P_ ((void));
477 #endif
478
479 #endif /* GC_MARK_STACK || GC_MALLOC_CHECK */
480
481 /* Recording what needs to be marked for gc. */
482
483 struct gcpro *gcprolist;
484
485 /* Addresses of staticpro'd variables. Initialize it to a nonzero
486 value; otherwise some compilers put it into BSS. */
487
488 #define NSTATICS 1280
489 Lisp_Object *staticvec[NSTATICS] = {&Vpurify_flag};
490
491 /* Index of next unused slot in staticvec. */
492
493 int staticidx = 0;
494
495 static POINTER_TYPE *pure_alloc P_ ((size_t, int));
496
497
498 /* Value is SZ rounded up to the next multiple of ALIGNMENT.
499 ALIGNMENT must be a power of 2. */
500
501 #define ALIGN(ptr, ALIGNMENT) \
502 ((POINTER_TYPE *) ((((EMACS_UINT)(ptr)) + (ALIGNMENT) - 1) \
503 & ~((ALIGNMENT) - 1)))
504
505
506 \f
507 /************************************************************************
508 Malloc
509 ************************************************************************/
510
511 /* Function malloc calls this if it finds we are near exhausting storage. */
512
513 void
514 malloc_warning (str)
515 char *str;
516 {
517 pending_malloc_warning = str;
518 }
519
520
521 /* Display an already-pending malloc warning. */
522
523 void
524 display_malloc_warning ()
525 {
526 call3 (intern ("display-warning"),
527 intern ("alloc"),
528 build_string (pending_malloc_warning),
529 intern ("emergency"));
530 pending_malloc_warning = 0;
531 }
532
533
534 #ifdef DOUG_LEA_MALLOC
535 # define BYTES_USED (mallinfo ().uordblks)
536 #else
537 # define BYTES_USED _bytes_used
538 #endif
539 \f
540 /* Called if we can't allocate relocatable space for a buffer. */
541
542 void
543 buffer_memory_full ()
544 {
545 /* If buffers use the relocating allocator, no need to free
546 spare_memory, because we may have plenty of malloc space left
547 that we could get, and if we don't, the malloc that fails will
548 itself cause spare_memory to be freed. If buffers don't use the
549 relocating allocator, treat this like any other failing
550 malloc. */
551
552 #ifndef REL_ALLOC
553 memory_full ();
554 #endif
555
556 /* This used to call error, but if we've run out of memory, we could
557 get infinite recursion trying to build the string. */
558 while (1)
559 Fsignal (Qnil, Vmemory_signal_data);
560 }
561
562
563 #ifdef XMALLOC_OVERRUN_CHECK
564
565 /* Check for overrun in malloc'ed buffers by wrapping a 16 byte header
566 and a 16 byte trailer around each block.
567
568 The header consists of 12 fixed bytes + a 4 byte integer contaning the
569 original block size, while the trailer consists of 16 fixed bytes.
570
571 The header is used to detect whether this block has been allocated
572 through these functions -- as it seems that some low-level libc
573 functions may bypass the malloc hooks.
574 */
575
576
577 #define XMALLOC_OVERRUN_CHECK_SIZE 16
578
579 static char xmalloc_overrun_check_header[XMALLOC_OVERRUN_CHECK_SIZE-4] =
580 { 0x9a, 0x9b, 0xae, 0xaf,
581 0xbf, 0xbe, 0xce, 0xcf,
582 0xea, 0xeb, 0xec, 0xed };
583
584 static char xmalloc_overrun_check_trailer[XMALLOC_OVERRUN_CHECK_SIZE] =
585 { 0xaa, 0xab, 0xac, 0xad,
586 0xba, 0xbb, 0xbc, 0xbd,
587 0xca, 0xcb, 0xcc, 0xcd,
588 0xda, 0xdb, 0xdc, 0xdd };
589
590 /* Macros to insert and extract the block size in the header. */
591
592 #define XMALLOC_PUT_SIZE(ptr, size) \
593 (ptr[-1] = (size & 0xff), \
594 ptr[-2] = ((size >> 8) & 0xff), \
595 ptr[-3] = ((size >> 16) & 0xff), \
596 ptr[-4] = ((size >> 24) & 0xff))
597
598 #define XMALLOC_GET_SIZE(ptr) \
599 (size_t)((unsigned)(ptr[-1]) | \
600 ((unsigned)(ptr[-2]) << 8) | \
601 ((unsigned)(ptr[-3]) << 16) | \
602 ((unsigned)(ptr[-4]) << 24))
603
604
605 /* The call depth in overrun_check functions. For example, this might happen:
606 xmalloc()
607 overrun_check_malloc()
608 -> malloc -> (via hook)_-> emacs_blocked_malloc
609 -> overrun_check_malloc
610 call malloc (hooks are NULL, so real malloc is called).
611 malloc returns 10000.
612 add overhead, return 10016.
613 <- (back in overrun_check_malloc)
614 add overhead again, return 10032
615 xmalloc returns 10032.
616
617 (time passes).
618
619 xfree(10032)
620 overrun_check_free(10032)
621 decrease overhed
622 free(10016) <- crash, because 10000 is the original pointer. */
623
624 static int check_depth;
625
626 /* Like malloc, but wraps allocated block with header and trailer. */
627
628 POINTER_TYPE *
629 overrun_check_malloc (size)
630 size_t size;
631 {
632 register unsigned char *val;
633 size_t overhead = ++check_depth == 1 ? XMALLOC_OVERRUN_CHECK_SIZE*2 : 0;
634
635 val = (unsigned char *) malloc (size + overhead);
636 if (val && check_depth == 1)
637 {
638 bcopy (xmalloc_overrun_check_header, val, XMALLOC_OVERRUN_CHECK_SIZE - 4);
639 val += XMALLOC_OVERRUN_CHECK_SIZE;
640 XMALLOC_PUT_SIZE(val, size);
641 bcopy (xmalloc_overrun_check_trailer, val + size, XMALLOC_OVERRUN_CHECK_SIZE);
642 }
643 --check_depth;
644 return (POINTER_TYPE *)val;
645 }
646
647
648 /* Like realloc, but checks old block for overrun, and wraps new block
649 with header and trailer. */
650
651 POINTER_TYPE *
652 overrun_check_realloc (block, size)
653 POINTER_TYPE *block;
654 size_t size;
655 {
656 register unsigned char *val = (unsigned char *)block;
657 size_t overhead = ++check_depth == 1 ? XMALLOC_OVERRUN_CHECK_SIZE*2 : 0;
658
659 if (val
660 && check_depth == 1
661 && bcmp (xmalloc_overrun_check_header,
662 val - XMALLOC_OVERRUN_CHECK_SIZE,
663 XMALLOC_OVERRUN_CHECK_SIZE - 4) == 0)
664 {
665 size_t osize = XMALLOC_GET_SIZE (val);
666 if (bcmp (xmalloc_overrun_check_trailer,
667 val + osize,
668 XMALLOC_OVERRUN_CHECK_SIZE))
669 abort ();
670 bzero (val + osize, XMALLOC_OVERRUN_CHECK_SIZE);
671 val -= XMALLOC_OVERRUN_CHECK_SIZE;
672 bzero (val, XMALLOC_OVERRUN_CHECK_SIZE);
673 }
674
675 val = (unsigned char *) realloc ((POINTER_TYPE *)val, size + overhead);
676
677 if (val && check_depth == 1)
678 {
679 bcopy (xmalloc_overrun_check_header, val, XMALLOC_OVERRUN_CHECK_SIZE - 4);
680 val += XMALLOC_OVERRUN_CHECK_SIZE;
681 XMALLOC_PUT_SIZE(val, size);
682 bcopy (xmalloc_overrun_check_trailer, val + size, XMALLOC_OVERRUN_CHECK_SIZE);
683 }
684 --check_depth;
685 return (POINTER_TYPE *)val;
686 }
687
688 /* Like free, but checks block for overrun. */
689
690 void
691 overrun_check_free (block)
692 POINTER_TYPE *block;
693 {
694 unsigned char *val = (unsigned char *)block;
695
696 ++check_depth;
697 if (val
698 && check_depth == 1
699 && bcmp (xmalloc_overrun_check_header,
700 val - XMALLOC_OVERRUN_CHECK_SIZE,
701 XMALLOC_OVERRUN_CHECK_SIZE - 4) == 0)
702 {
703 size_t osize = XMALLOC_GET_SIZE (val);
704 if (bcmp (xmalloc_overrun_check_trailer,
705 val + osize,
706 XMALLOC_OVERRUN_CHECK_SIZE))
707 abort ();
708 #ifdef XMALLOC_CLEAR_FREE_MEMORY
709 val -= XMALLOC_OVERRUN_CHECK_SIZE;
710 memset (val, 0xff, osize + XMALLOC_OVERRUN_CHECK_SIZE*2);
711 #else
712 bzero (val + osize, XMALLOC_OVERRUN_CHECK_SIZE);
713 val -= XMALLOC_OVERRUN_CHECK_SIZE;
714 bzero (val, XMALLOC_OVERRUN_CHECK_SIZE);
715 #endif
716 }
717
718 free (val);
719 --check_depth;
720 }
721
722 #undef malloc
723 #undef realloc
724 #undef free
725 #define malloc overrun_check_malloc
726 #define realloc overrun_check_realloc
727 #define free overrun_check_free
728 #endif
729
730
731 /* Like malloc but check for no memory and block interrupt input.. */
732
733 POINTER_TYPE *
734 xmalloc (size)
735 size_t size;
736 {
737 register POINTER_TYPE *val;
738
739 BLOCK_INPUT;
740 val = (POINTER_TYPE *) malloc (size);
741 UNBLOCK_INPUT;
742
743 if (!val && size)
744 memory_full ();
745 return val;
746 }
747
748
749 /* Like realloc but check for no memory and block interrupt input.. */
750
751 POINTER_TYPE *
752 xrealloc (block, size)
753 POINTER_TYPE *block;
754 size_t size;
755 {
756 register POINTER_TYPE *val;
757
758 BLOCK_INPUT;
759 /* We must call malloc explicitly when BLOCK is 0, since some
760 reallocs don't do this. */
761 if (! block)
762 val = (POINTER_TYPE *) malloc (size);
763 else
764 val = (POINTER_TYPE *) realloc (block, size);
765 UNBLOCK_INPUT;
766
767 if (!val && size) memory_full ();
768 return val;
769 }
770
771
772 /* Like free but block interrupt input. */
773
774 void
775 xfree (block)
776 POINTER_TYPE *block;
777 {
778 BLOCK_INPUT;
779 free (block);
780 UNBLOCK_INPUT;
781 /* We don't call refill_memory_reserve here
782 because that duplicates doing so in emacs_blocked_free
783 and the criterion should go there. */
784 }
785
786
787 /* Like strdup, but uses xmalloc. */
788
789 char *
790 xstrdup (s)
791 const char *s;
792 {
793 size_t len = strlen (s) + 1;
794 char *p = (char *) xmalloc (len);
795 bcopy (s, p, len);
796 return p;
797 }
798
799
800 /* Unwind for SAFE_ALLOCA */
801
802 Lisp_Object
803 safe_alloca_unwind (arg)
804 Lisp_Object arg;
805 {
806 register struct Lisp_Save_Value *p = XSAVE_VALUE (arg);
807
808 p->dogc = 0;
809 xfree (p->pointer);
810 p->pointer = 0;
811 free_misc (arg);
812 return Qnil;
813 }
814
815
816 /* Like malloc but used for allocating Lisp data. NBYTES is the
817 number of bytes to allocate, TYPE describes the intended use of the
818 allcated memory block (for strings, for conses, ...). */
819
820 #ifndef USE_LSB_TAG
821 static void *lisp_malloc_loser;
822 #endif
823
824 static POINTER_TYPE *
825 lisp_malloc (nbytes, type)
826 size_t nbytes;
827 enum mem_type type;
828 {
829 register void *val;
830
831 BLOCK_INPUT;
832
833 #ifdef GC_MALLOC_CHECK
834 allocated_mem_type = type;
835 #endif
836
837 val = (void *) malloc (nbytes);
838
839 #ifndef USE_LSB_TAG
840 /* If the memory just allocated cannot be addressed thru a Lisp
841 object's pointer, and it needs to be,
842 that's equivalent to running out of memory. */
843 if (val && type != MEM_TYPE_NON_LISP)
844 {
845 Lisp_Object tem;
846 XSETCONS (tem, (char *) val + nbytes - 1);
847 if ((char *) XCONS (tem) != (char *) val + nbytes - 1)
848 {
849 lisp_malloc_loser = val;
850 free (val);
851 val = 0;
852 }
853 }
854 #endif
855
856 #if GC_MARK_STACK && !defined GC_MALLOC_CHECK
857 if (val && type != MEM_TYPE_NON_LISP)
858 mem_insert (val, (char *) val + nbytes, type);
859 #endif
860
861 UNBLOCK_INPUT;
862 if (!val && nbytes)
863 memory_full ();
864 return val;
865 }
866
867 /* Free BLOCK. This must be called to free memory allocated with a
868 call to lisp_malloc. */
869
870 static void
871 lisp_free (block)
872 POINTER_TYPE *block;
873 {
874 BLOCK_INPUT;
875 free (block);
876 #if GC_MARK_STACK && !defined GC_MALLOC_CHECK
877 mem_delete (mem_find (block));
878 #endif
879 UNBLOCK_INPUT;
880 }
881
882 /* Allocation of aligned blocks of memory to store Lisp data. */
883 /* The entry point is lisp_align_malloc which returns blocks of at most */
884 /* BLOCK_BYTES and guarantees they are aligned on a BLOCK_ALIGN boundary. */
885
886
887 /* BLOCK_ALIGN has to be a power of 2. */
888 #define BLOCK_ALIGN (1 << 10)
889
890 /* Padding to leave at the end of a malloc'd block. This is to give
891 malloc a chance to minimize the amount of memory wasted to alignment.
892 It should be tuned to the particular malloc library used.
893 On glibc-2.3.2, malloc never tries to align, so a padding of 0 is best.
894 posix_memalign on the other hand would ideally prefer a value of 4
895 because otherwise, there's 1020 bytes wasted between each ablocks.
896 In Emacs, testing shows that those 1020 can most of the time be
897 efficiently used by malloc to place other objects, so a value of 0 can
898 still preferable unless you have a lot of aligned blocks and virtually
899 nothing else. */
900 #define BLOCK_PADDING 0
901 #define BLOCK_BYTES \
902 (BLOCK_ALIGN - sizeof (struct ablock *) - BLOCK_PADDING)
903
904 /* Internal data structures and constants. */
905
906 #define ABLOCKS_SIZE 16
907
908 /* An aligned block of memory. */
909 struct ablock
910 {
911 union
912 {
913 char payload[BLOCK_BYTES];
914 struct ablock *next_free;
915 } x;
916 /* `abase' is the aligned base of the ablocks. */
917 /* It is overloaded to hold the virtual `busy' field that counts
918 the number of used ablock in the parent ablocks.
919 The first ablock has the `busy' field, the others have the `abase'
920 field. To tell the difference, we assume that pointers will have
921 integer values larger than 2 * ABLOCKS_SIZE. The lowest bit of `busy'
922 is used to tell whether the real base of the parent ablocks is `abase'
923 (if not, the word before the first ablock holds a pointer to the
924 real base). */
925 struct ablocks *abase;
926 /* The padding of all but the last ablock is unused. The padding of
927 the last ablock in an ablocks is not allocated. */
928 #if BLOCK_PADDING
929 char padding[BLOCK_PADDING];
930 #endif
931 };
932
933 /* A bunch of consecutive aligned blocks. */
934 struct ablocks
935 {
936 struct ablock blocks[ABLOCKS_SIZE];
937 };
938
939 /* Size of the block requested from malloc or memalign. */
940 #define ABLOCKS_BYTES (sizeof (struct ablocks) - BLOCK_PADDING)
941
942 #define ABLOCK_ABASE(block) \
943 (((unsigned long) (block)->abase) <= (1 + 2 * ABLOCKS_SIZE) \
944 ? (struct ablocks *)(block) \
945 : (block)->abase)
946
947 /* Virtual `busy' field. */
948 #define ABLOCKS_BUSY(abase) ((abase)->blocks[0].abase)
949
950 /* Pointer to the (not necessarily aligned) malloc block. */
951 #ifdef HAVE_POSIX_MEMALIGN
952 #define ABLOCKS_BASE(abase) (abase)
953 #else
954 #define ABLOCKS_BASE(abase) \
955 (1 & (long) ABLOCKS_BUSY (abase) ? abase : ((void**)abase)[-1])
956 #endif
957
958 /* The list of free ablock. */
959 static struct ablock *free_ablock;
960
961 /* Allocate an aligned block of nbytes.
962 Alignment is on a multiple of BLOCK_ALIGN and `nbytes' has to be
963 smaller or equal to BLOCK_BYTES. */
964 static POINTER_TYPE *
965 lisp_align_malloc (nbytes, type)
966 size_t nbytes;
967 enum mem_type type;
968 {
969 void *base, *val;
970 struct ablocks *abase;
971
972 eassert (nbytes <= BLOCK_BYTES);
973
974 BLOCK_INPUT;
975
976 #ifdef GC_MALLOC_CHECK
977 allocated_mem_type = type;
978 #endif
979
980 if (!free_ablock)
981 {
982 int i;
983 EMACS_INT aligned; /* int gets warning casting to 64-bit pointer. */
984
985 #ifdef DOUG_LEA_MALLOC
986 /* Prevent mmap'ing the chunk. Lisp data may not be mmap'ed
987 because mapped region contents are not preserved in
988 a dumped Emacs. */
989 mallopt (M_MMAP_MAX, 0);
990 #endif
991
992 #ifdef HAVE_POSIX_MEMALIGN
993 {
994 int err = posix_memalign (&base, BLOCK_ALIGN, ABLOCKS_BYTES);
995 if (err)
996 base = NULL;
997 abase = base;
998 }
999 #else
1000 base = malloc (ABLOCKS_BYTES);
1001 abase = ALIGN (base, BLOCK_ALIGN);
1002 #endif
1003
1004 if (base == 0)
1005 {
1006 UNBLOCK_INPUT;
1007 memory_full ();
1008 }
1009
1010 aligned = (base == abase);
1011 if (!aligned)
1012 ((void**)abase)[-1] = base;
1013
1014 #ifdef DOUG_LEA_MALLOC
1015 /* Back to a reasonable maximum of mmap'ed areas. */
1016 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
1017 #endif
1018
1019 #ifndef USE_LSB_TAG
1020 /* If the memory just allocated cannot be addressed thru a Lisp
1021 object's pointer, and it needs to be, that's equivalent to
1022 running out of memory. */
1023 if (type != MEM_TYPE_NON_LISP)
1024 {
1025 Lisp_Object tem;
1026 char *end = (char *) base + ABLOCKS_BYTES - 1;
1027 XSETCONS (tem, end);
1028 if ((char *) XCONS (tem) != end)
1029 {
1030 lisp_malloc_loser = base;
1031 free (base);
1032 UNBLOCK_INPUT;
1033 memory_full ();
1034 }
1035 }
1036 #endif
1037
1038 /* Initialize the blocks and put them on the free list.
1039 Is `base' was not properly aligned, we can't use the last block. */
1040 for (i = 0; i < (aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1); i++)
1041 {
1042 abase->blocks[i].abase = abase;
1043 abase->blocks[i].x.next_free = free_ablock;
1044 free_ablock = &abase->blocks[i];
1045 }
1046 ABLOCKS_BUSY (abase) = (struct ablocks *) (long) aligned;
1047
1048 eassert (0 == ((EMACS_UINT)abase) % BLOCK_ALIGN);
1049 eassert (ABLOCK_ABASE (&abase->blocks[3]) == abase); /* 3 is arbitrary */
1050 eassert (ABLOCK_ABASE (&abase->blocks[0]) == abase);
1051 eassert (ABLOCKS_BASE (abase) == base);
1052 eassert (aligned == (long) ABLOCKS_BUSY (abase));
1053 }
1054
1055 abase = ABLOCK_ABASE (free_ablock);
1056 ABLOCKS_BUSY (abase) = (struct ablocks *) (2 + (long) ABLOCKS_BUSY (abase));
1057 val = free_ablock;
1058 free_ablock = free_ablock->x.next_free;
1059
1060 #if GC_MARK_STACK && !defined GC_MALLOC_CHECK
1061 if (val && type != MEM_TYPE_NON_LISP)
1062 mem_insert (val, (char *) val + nbytes, type);
1063 #endif
1064
1065 UNBLOCK_INPUT;
1066 if (!val && nbytes)
1067 memory_full ();
1068
1069 eassert (0 == ((EMACS_UINT)val) % BLOCK_ALIGN);
1070 return val;
1071 }
1072
1073 static void
1074 lisp_align_free (block)
1075 POINTER_TYPE *block;
1076 {
1077 struct ablock *ablock = block;
1078 struct ablocks *abase = ABLOCK_ABASE (ablock);
1079
1080 BLOCK_INPUT;
1081 #if GC_MARK_STACK && !defined GC_MALLOC_CHECK
1082 mem_delete (mem_find (block));
1083 #endif
1084 /* Put on free list. */
1085 ablock->x.next_free = free_ablock;
1086 free_ablock = ablock;
1087 /* Update busy count. */
1088 ABLOCKS_BUSY (abase) = (struct ablocks *) (-2 + (long) ABLOCKS_BUSY (abase));
1089
1090 if (2 > (long) ABLOCKS_BUSY (abase))
1091 { /* All the blocks are free. */
1092 int i = 0, aligned = (long) ABLOCKS_BUSY (abase);
1093 struct ablock **tem = &free_ablock;
1094 struct ablock *atop = &abase->blocks[aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1];
1095
1096 while (*tem)
1097 {
1098 if (*tem >= (struct ablock *) abase && *tem < atop)
1099 {
1100 i++;
1101 *tem = (*tem)->x.next_free;
1102 }
1103 else
1104 tem = &(*tem)->x.next_free;
1105 }
1106 eassert ((aligned & 1) == aligned);
1107 eassert (i == (aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1));
1108 free (ABLOCKS_BASE (abase));
1109 }
1110 UNBLOCK_INPUT;
1111 }
1112
1113 /* Return a new buffer structure allocated from the heap with
1114 a call to lisp_malloc. */
1115
1116 struct buffer *
1117 allocate_buffer ()
1118 {
1119 struct buffer *b
1120 = (struct buffer *) lisp_malloc (sizeof (struct buffer),
1121 MEM_TYPE_BUFFER);
1122 return b;
1123 }
1124
1125 \f
1126 #ifndef SYSTEM_MALLOC
1127
1128 /* Arranging to disable input signals while we're in malloc.
1129
1130 This only works with GNU malloc. To help out systems which can't
1131 use GNU malloc, all the calls to malloc, realloc, and free
1132 elsewhere in the code should be inside a BLOCK_INPUT/UNBLOCK_INPUT
1133 pair; unfortunately, we have no idea what C library functions
1134 might call malloc, so we can't really protect them unless you're
1135 using GNU malloc. Fortunately, most of the major operating systems
1136 can use GNU malloc. */
1137
1138 #ifndef SYNC_INPUT
1139
1140 #ifndef DOUG_LEA_MALLOC
1141 extern void * (*__malloc_hook) P_ ((size_t, const void *));
1142 extern void * (*__realloc_hook) P_ ((void *, size_t, const void *));
1143 extern void (*__free_hook) P_ ((void *, const void *));
1144 /* Else declared in malloc.h, perhaps with an extra arg. */
1145 #endif /* DOUG_LEA_MALLOC */
1146 static void * (*old_malloc_hook) P_ ((size_t, const void *));
1147 static void * (*old_realloc_hook) P_ ((void *, size_t, const void*));
1148 static void (*old_free_hook) P_ ((void*, const void*));
1149
1150 /* This function is used as the hook for free to call. */
1151
1152 static void
1153 emacs_blocked_free (ptr, ptr2)
1154 void *ptr;
1155 const void *ptr2;
1156 {
1157 EMACS_INT bytes_used_now;
1158
1159 BLOCK_INPUT_ALLOC;
1160
1161 #ifdef GC_MALLOC_CHECK
1162 if (ptr)
1163 {
1164 struct mem_node *m;
1165
1166 m = mem_find (ptr);
1167 if (m == MEM_NIL || m->start != ptr)
1168 {
1169 fprintf (stderr,
1170 "Freeing `%p' which wasn't allocated with malloc\n", ptr);
1171 abort ();
1172 }
1173 else
1174 {
1175 /* fprintf (stderr, "free %p...%p (%p)\n", m->start, m->end, ptr); */
1176 mem_delete (m);
1177 }
1178 }
1179 #endif /* GC_MALLOC_CHECK */
1180
1181 __free_hook = old_free_hook;
1182 free (ptr);
1183
1184 /* If we released our reserve (due to running out of memory),
1185 and we have a fair amount free once again,
1186 try to set aside another reserve in case we run out once more. */
1187 if (! NILP (Vmemory_full)
1188 /* Verify there is enough space that even with the malloc
1189 hysteresis this call won't run out again.
1190 The code here is correct as long as SPARE_MEMORY
1191 is substantially larger than the block size malloc uses. */
1192 && (bytes_used_when_full
1193 > ((bytes_used_when_reconsidered = BYTES_USED)
1194 + max (malloc_hysteresis, 4) * SPARE_MEMORY)))
1195 refill_memory_reserve ();
1196
1197 __free_hook = emacs_blocked_free;
1198 UNBLOCK_INPUT_ALLOC;
1199 }
1200
1201
1202 /* This function is the malloc hook that Emacs uses. */
1203
1204 static void *
1205 emacs_blocked_malloc (size, ptr)
1206 size_t size;
1207 const void *ptr;
1208 {
1209 void *value;
1210
1211 BLOCK_INPUT_ALLOC;
1212 __malloc_hook = old_malloc_hook;
1213 #ifdef DOUG_LEA_MALLOC
1214 mallopt (M_TOP_PAD, malloc_hysteresis * 4096);
1215 #else
1216 __malloc_extra_blocks = malloc_hysteresis;
1217 #endif
1218
1219 value = (void *) malloc (size);
1220
1221 #ifdef GC_MALLOC_CHECK
1222 {
1223 struct mem_node *m = mem_find (value);
1224 if (m != MEM_NIL)
1225 {
1226 fprintf (stderr, "Malloc returned %p which is already in use\n",
1227 value);
1228 fprintf (stderr, "Region in use is %p...%p, %u bytes, type %d\n",
1229 m->start, m->end, (char *) m->end - (char *) m->start,
1230 m->type);
1231 abort ();
1232 }
1233
1234 if (!dont_register_blocks)
1235 {
1236 mem_insert (value, (char *) value + max (1, size), allocated_mem_type);
1237 allocated_mem_type = MEM_TYPE_NON_LISP;
1238 }
1239 }
1240 #endif /* GC_MALLOC_CHECK */
1241
1242 __malloc_hook = emacs_blocked_malloc;
1243 UNBLOCK_INPUT_ALLOC;
1244
1245 /* fprintf (stderr, "%p malloc\n", value); */
1246 return value;
1247 }
1248
1249
1250 /* This function is the realloc hook that Emacs uses. */
1251
1252 static void *
1253 emacs_blocked_realloc (ptr, size, ptr2)
1254 void *ptr;
1255 size_t size;
1256 const void *ptr2;
1257 {
1258 void *value;
1259
1260 BLOCK_INPUT_ALLOC;
1261 __realloc_hook = old_realloc_hook;
1262
1263 #ifdef GC_MALLOC_CHECK
1264 if (ptr)
1265 {
1266 struct mem_node *m = mem_find (ptr);
1267 if (m == MEM_NIL || m->start != ptr)
1268 {
1269 fprintf (stderr,
1270 "Realloc of %p which wasn't allocated with malloc\n",
1271 ptr);
1272 abort ();
1273 }
1274
1275 mem_delete (m);
1276 }
1277
1278 /* fprintf (stderr, "%p -> realloc\n", ptr); */
1279
1280 /* Prevent malloc from registering blocks. */
1281 dont_register_blocks = 1;
1282 #endif /* GC_MALLOC_CHECK */
1283
1284 value = (void *) realloc (ptr, size);
1285
1286 #ifdef GC_MALLOC_CHECK
1287 dont_register_blocks = 0;
1288
1289 {
1290 struct mem_node *m = mem_find (value);
1291 if (m != MEM_NIL)
1292 {
1293 fprintf (stderr, "Realloc returns memory that is already in use\n");
1294 abort ();
1295 }
1296
1297 /* Can't handle zero size regions in the red-black tree. */
1298 mem_insert (value, (char *) value + max (size, 1), MEM_TYPE_NON_LISP);
1299 }
1300
1301 /* fprintf (stderr, "%p <- realloc\n", value); */
1302 #endif /* GC_MALLOC_CHECK */
1303
1304 __realloc_hook = emacs_blocked_realloc;
1305 UNBLOCK_INPUT_ALLOC;
1306
1307 return value;
1308 }
1309
1310
1311 #ifdef HAVE_GTK_AND_PTHREAD
1312 /* Called from Fdump_emacs so that when the dumped Emacs starts, it has a
1313 normal malloc. Some thread implementations need this as they call
1314 malloc before main. The pthread_self call in BLOCK_INPUT_ALLOC then
1315 calls malloc because it is the first call, and we have an endless loop. */
1316
1317 void
1318 reset_malloc_hooks ()
1319 {
1320 __free_hook = 0;
1321 __malloc_hook = 0;
1322 __realloc_hook = 0;
1323 }
1324 #endif /* HAVE_GTK_AND_PTHREAD */
1325
1326
1327 /* Called from main to set up malloc to use our hooks. */
1328
1329 void
1330 uninterrupt_malloc ()
1331 {
1332 #ifdef HAVE_GTK_AND_PTHREAD
1333 pthread_mutexattr_t attr;
1334
1335 /* GLIBC has a faster way to do this, but lets keep it portable.
1336 This is according to the Single UNIX Specification. */
1337 pthread_mutexattr_init (&attr);
1338 pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE);
1339 pthread_mutex_init (&alloc_mutex, &attr);
1340 #endif /* HAVE_GTK_AND_PTHREAD */
1341
1342 if (__free_hook != emacs_blocked_free)
1343 old_free_hook = __free_hook;
1344 __free_hook = emacs_blocked_free;
1345
1346 if (__malloc_hook != emacs_blocked_malloc)
1347 old_malloc_hook = __malloc_hook;
1348 __malloc_hook = emacs_blocked_malloc;
1349
1350 if (__realloc_hook != emacs_blocked_realloc)
1351 old_realloc_hook = __realloc_hook;
1352 __realloc_hook = emacs_blocked_realloc;
1353 }
1354
1355 #endif /* not SYNC_INPUT */
1356 #endif /* not SYSTEM_MALLOC */
1357
1358
1359 \f
1360 /***********************************************************************
1361 Interval Allocation
1362 ***********************************************************************/
1363
1364 /* Number of intervals allocated in an interval_block structure.
1365 The 1020 is 1024 minus malloc overhead. */
1366
1367 #define INTERVAL_BLOCK_SIZE \
1368 ((1020 - sizeof (struct interval_block *)) / sizeof (struct interval))
1369
1370 /* Intervals are allocated in chunks in form of an interval_block
1371 structure. */
1372
1373 struct interval_block
1374 {
1375 /* Place `intervals' first, to preserve alignment. */
1376 struct interval intervals[INTERVAL_BLOCK_SIZE];
1377 struct interval_block *next;
1378 };
1379
1380 /* Current interval block. Its `next' pointer points to older
1381 blocks. */
1382
1383 struct interval_block *interval_block;
1384
1385 /* Index in interval_block above of the next unused interval
1386 structure. */
1387
1388 static int interval_block_index;
1389
1390 /* Number of free and live intervals. */
1391
1392 static int total_free_intervals, total_intervals;
1393
1394 /* List of free intervals. */
1395
1396 INTERVAL interval_free_list;
1397
1398 /* Total number of interval blocks now in use. */
1399
1400 int n_interval_blocks;
1401
1402
1403 /* Initialize interval allocation. */
1404
1405 static void
1406 init_intervals ()
1407 {
1408 interval_block = NULL;
1409 interval_block_index = INTERVAL_BLOCK_SIZE;
1410 interval_free_list = 0;
1411 n_interval_blocks = 0;
1412 }
1413
1414
1415 /* Return a new interval. */
1416
1417 INTERVAL
1418 make_interval ()
1419 {
1420 INTERVAL val;
1421
1422 if (interval_free_list)
1423 {
1424 val = interval_free_list;
1425 interval_free_list = INTERVAL_PARENT (interval_free_list);
1426 }
1427 else
1428 {
1429 if (interval_block_index == INTERVAL_BLOCK_SIZE)
1430 {
1431 register struct interval_block *newi;
1432
1433 newi = (struct interval_block *) lisp_malloc (sizeof *newi,
1434 MEM_TYPE_NON_LISP);
1435
1436 newi->next = interval_block;
1437 interval_block = newi;
1438 interval_block_index = 0;
1439 n_interval_blocks++;
1440 }
1441 val = &interval_block->intervals[interval_block_index++];
1442 }
1443 consing_since_gc += sizeof (struct interval);
1444 intervals_consed++;
1445 RESET_INTERVAL (val);
1446 val->gcmarkbit = 0;
1447 return val;
1448 }
1449
1450
1451 /* Mark Lisp objects in interval I. */
1452
1453 static void
1454 mark_interval (i, dummy)
1455 register INTERVAL i;
1456 Lisp_Object dummy;
1457 {
1458 eassert (!i->gcmarkbit); /* Intervals are never shared. */
1459 i->gcmarkbit = 1;
1460 mark_object (i->plist);
1461 }
1462
1463
1464 /* Mark the interval tree rooted in TREE. Don't call this directly;
1465 use the macro MARK_INTERVAL_TREE instead. */
1466
1467 static void
1468 mark_interval_tree (tree)
1469 register INTERVAL tree;
1470 {
1471 /* No need to test if this tree has been marked already; this
1472 function is always called through the MARK_INTERVAL_TREE macro,
1473 which takes care of that. */
1474
1475 traverse_intervals_noorder (tree, mark_interval, Qnil);
1476 }
1477
1478
1479 /* Mark the interval tree rooted in I. */
1480
1481 #define MARK_INTERVAL_TREE(i) \
1482 do { \
1483 if (!NULL_INTERVAL_P (i) && !i->gcmarkbit) \
1484 mark_interval_tree (i); \
1485 } while (0)
1486
1487
1488 #define UNMARK_BALANCE_INTERVALS(i) \
1489 do { \
1490 if (! NULL_INTERVAL_P (i)) \
1491 (i) = balance_intervals (i); \
1492 } while (0)
1493
1494 \f
1495 /* Number support. If NO_UNION_TYPE isn't in effect, we
1496 can't create number objects in macros. */
1497 #ifndef make_number
1498 Lisp_Object
1499 make_number (n)
1500 EMACS_INT n;
1501 {
1502 Lisp_Object obj;
1503 obj.s.val = n;
1504 obj.s.type = Lisp_Int;
1505 return obj;
1506 }
1507 #endif
1508 \f
1509 /***********************************************************************
1510 String Allocation
1511 ***********************************************************************/
1512
1513 /* Lisp_Strings are allocated in string_block structures. When a new
1514 string_block is allocated, all the Lisp_Strings it contains are
1515 added to a free-list string_free_list. When a new Lisp_String is
1516 needed, it is taken from that list. During the sweep phase of GC,
1517 string_blocks that are entirely free are freed, except two which
1518 we keep.
1519
1520 String data is allocated from sblock structures. Strings larger
1521 than LARGE_STRING_BYTES, get their own sblock, data for smaller
1522 strings is sub-allocated out of sblocks of size SBLOCK_SIZE.
1523
1524 Sblocks consist internally of sdata structures, one for each
1525 Lisp_String. The sdata structure points to the Lisp_String it
1526 belongs to. The Lisp_String points back to the `u.data' member of
1527 its sdata structure.
1528
1529 When a Lisp_String is freed during GC, it is put back on
1530 string_free_list, and its `data' member and its sdata's `string'
1531 pointer is set to null. The size of the string is recorded in the
1532 `u.nbytes' member of the sdata. So, sdata structures that are no
1533 longer used, can be easily recognized, and it's easy to compact the
1534 sblocks of small strings which we do in compact_small_strings. */
1535
1536 /* Size in bytes of an sblock structure used for small strings. This
1537 is 8192 minus malloc overhead. */
1538
1539 #define SBLOCK_SIZE 8188
1540
1541 /* Strings larger than this are considered large strings. String data
1542 for large strings is allocated from individual sblocks. */
1543
1544 #define LARGE_STRING_BYTES 1024
1545
1546 /* Structure describing string memory sub-allocated from an sblock.
1547 This is where the contents of Lisp strings are stored. */
1548
1549 struct sdata
1550 {
1551 /* Back-pointer to the string this sdata belongs to. If null, this
1552 structure is free, and the NBYTES member of the union below
1553 contains the string's byte size (the same value that STRING_BYTES
1554 would return if STRING were non-null). If non-null, STRING_BYTES
1555 (STRING) is the size of the data, and DATA contains the string's
1556 contents. */
1557 struct Lisp_String *string;
1558
1559 #ifdef GC_CHECK_STRING_BYTES
1560
1561 EMACS_INT nbytes;
1562 unsigned char data[1];
1563
1564 #define SDATA_NBYTES(S) (S)->nbytes
1565 #define SDATA_DATA(S) (S)->data
1566
1567 #else /* not GC_CHECK_STRING_BYTES */
1568
1569 union
1570 {
1571 /* When STRING in non-null. */
1572 unsigned char data[1];
1573
1574 /* When STRING is null. */
1575 EMACS_INT nbytes;
1576 } u;
1577
1578
1579 #define SDATA_NBYTES(S) (S)->u.nbytes
1580 #define SDATA_DATA(S) (S)->u.data
1581
1582 #endif /* not GC_CHECK_STRING_BYTES */
1583 };
1584
1585
1586 /* Structure describing a block of memory which is sub-allocated to
1587 obtain string data memory for strings. Blocks for small strings
1588 are of fixed size SBLOCK_SIZE. Blocks for large strings are made
1589 as large as needed. */
1590
1591 struct sblock
1592 {
1593 /* Next in list. */
1594 struct sblock *next;
1595
1596 /* Pointer to the next free sdata block. This points past the end
1597 of the sblock if there isn't any space left in this block. */
1598 struct sdata *next_free;
1599
1600 /* Start of data. */
1601 struct sdata first_data;
1602 };
1603
1604 /* Number of Lisp strings in a string_block structure. The 1020 is
1605 1024 minus malloc overhead. */
1606
1607 #define STRING_BLOCK_SIZE \
1608 ((1020 - sizeof (struct string_block *)) / sizeof (struct Lisp_String))
1609
1610 /* Structure describing a block from which Lisp_String structures
1611 are allocated. */
1612
1613 struct string_block
1614 {
1615 /* Place `strings' first, to preserve alignment. */
1616 struct Lisp_String strings[STRING_BLOCK_SIZE];
1617 struct string_block *next;
1618 };
1619
1620 /* Head and tail of the list of sblock structures holding Lisp string
1621 data. We always allocate from current_sblock. The NEXT pointers
1622 in the sblock structures go from oldest_sblock to current_sblock. */
1623
1624 static struct sblock *oldest_sblock, *current_sblock;
1625
1626 /* List of sblocks for large strings. */
1627
1628 static struct sblock *large_sblocks;
1629
1630 /* List of string_block structures, and how many there are. */
1631
1632 static struct string_block *string_blocks;
1633 static int n_string_blocks;
1634
1635 /* Free-list of Lisp_Strings. */
1636
1637 static struct Lisp_String *string_free_list;
1638
1639 /* Number of live and free Lisp_Strings. */
1640
1641 static int total_strings, total_free_strings;
1642
1643 /* Number of bytes used by live strings. */
1644
1645 static int total_string_size;
1646
1647 /* Given a pointer to a Lisp_String S which is on the free-list
1648 string_free_list, return a pointer to its successor in the
1649 free-list. */
1650
1651 #define NEXT_FREE_LISP_STRING(S) (*(struct Lisp_String **) (S))
1652
1653 /* Return a pointer to the sdata structure belonging to Lisp string S.
1654 S must be live, i.e. S->data must not be null. S->data is actually
1655 a pointer to the `u.data' member of its sdata structure; the
1656 structure starts at a constant offset in front of that. */
1657
1658 #ifdef GC_CHECK_STRING_BYTES
1659
1660 #define SDATA_OF_STRING(S) \
1661 ((struct sdata *) ((S)->data - sizeof (struct Lisp_String *) \
1662 - sizeof (EMACS_INT)))
1663
1664 #else /* not GC_CHECK_STRING_BYTES */
1665
1666 #define SDATA_OF_STRING(S) \
1667 ((struct sdata *) ((S)->data - sizeof (struct Lisp_String *)))
1668
1669 #endif /* not GC_CHECK_STRING_BYTES */
1670
1671
1672 #ifdef GC_CHECK_STRING_OVERRUN
1673
1674 /* We check for overrun in string data blocks by appending a small
1675 "cookie" after each allocated string data block, and check for the
1676 presence of this cookie during GC. */
1677
1678 #define GC_STRING_OVERRUN_COOKIE_SIZE 4
1679 static char string_overrun_cookie[GC_STRING_OVERRUN_COOKIE_SIZE] =
1680 { 0xde, 0xad, 0xbe, 0xef };
1681
1682 #else
1683 #define GC_STRING_OVERRUN_COOKIE_SIZE 0
1684 #endif
1685
1686 /* Value is the size of an sdata structure large enough to hold NBYTES
1687 bytes of string data. The value returned includes a terminating
1688 NUL byte, the size of the sdata structure, and padding. */
1689
1690 #ifdef GC_CHECK_STRING_BYTES
1691
1692 #define SDATA_SIZE(NBYTES) \
1693 ((sizeof (struct Lisp_String *) \
1694 + (NBYTES) + 1 \
1695 + sizeof (EMACS_INT) \
1696 + sizeof (EMACS_INT) - 1) \
1697 & ~(sizeof (EMACS_INT) - 1))
1698
1699 #else /* not GC_CHECK_STRING_BYTES */
1700
1701 #define SDATA_SIZE(NBYTES) \
1702 ((sizeof (struct Lisp_String *) \
1703 + (NBYTES) + 1 \
1704 + sizeof (EMACS_INT) - 1) \
1705 & ~(sizeof (EMACS_INT) - 1))
1706
1707 #endif /* not GC_CHECK_STRING_BYTES */
1708
1709 /* Extra bytes to allocate for each string. */
1710
1711 #define GC_STRING_EXTRA (GC_STRING_OVERRUN_COOKIE_SIZE)
1712
1713 /* Initialize string allocation. Called from init_alloc_once. */
1714
1715 void
1716 init_strings ()
1717 {
1718 total_strings = total_free_strings = total_string_size = 0;
1719 oldest_sblock = current_sblock = large_sblocks = NULL;
1720 string_blocks = NULL;
1721 n_string_blocks = 0;
1722 string_free_list = NULL;
1723 }
1724
1725
1726 #ifdef GC_CHECK_STRING_BYTES
1727
1728 static int check_string_bytes_count;
1729
1730 void check_string_bytes P_ ((int));
1731 void check_sblock P_ ((struct sblock *));
1732
1733 #define CHECK_STRING_BYTES(S) STRING_BYTES (S)
1734
1735
1736 /* Like GC_STRING_BYTES, but with debugging check. */
1737
1738 int
1739 string_bytes (s)
1740 struct Lisp_String *s;
1741 {
1742 int nbytes = (s->size_byte < 0 ? s->size & ~ARRAY_MARK_FLAG : s->size_byte);
1743 if (!PURE_POINTER_P (s)
1744 && s->data
1745 && nbytes != SDATA_NBYTES (SDATA_OF_STRING (s)))
1746 abort ();
1747 return nbytes;
1748 }
1749
1750 /* Check validity of Lisp strings' string_bytes member in B. */
1751
1752 void
1753 check_sblock (b)
1754 struct sblock *b;
1755 {
1756 struct sdata *from, *end, *from_end;
1757
1758 end = b->next_free;
1759
1760 for (from = &b->first_data; from < end; from = from_end)
1761 {
1762 /* Compute the next FROM here because copying below may
1763 overwrite data we need to compute it. */
1764 int nbytes;
1765
1766 /* Check that the string size recorded in the string is the
1767 same as the one recorded in the sdata structure. */
1768 if (from->string)
1769 CHECK_STRING_BYTES (from->string);
1770
1771 if (from->string)
1772 nbytes = GC_STRING_BYTES (from->string);
1773 else
1774 nbytes = SDATA_NBYTES (from);
1775
1776 nbytes = SDATA_SIZE (nbytes);
1777 from_end = (struct sdata *) ((char *) from + nbytes + GC_STRING_EXTRA);
1778 }
1779 }
1780
1781
1782 /* Check validity of Lisp strings' string_bytes member. ALL_P
1783 non-zero means check all strings, otherwise check only most
1784 recently allocated strings. Used for hunting a bug. */
1785
1786 void
1787 check_string_bytes (all_p)
1788 int all_p;
1789 {
1790 if (all_p)
1791 {
1792 struct sblock *b;
1793
1794 for (b = large_sblocks; b; b = b->next)
1795 {
1796 struct Lisp_String *s = b->first_data.string;
1797 if (s)
1798 CHECK_STRING_BYTES (s);
1799 }
1800
1801 for (b = oldest_sblock; b; b = b->next)
1802 check_sblock (b);
1803 }
1804 else
1805 check_sblock (current_sblock);
1806 }
1807
1808 #endif /* GC_CHECK_STRING_BYTES */
1809
1810 #ifdef GC_CHECK_STRING_FREE_LIST
1811
1812 /* Walk through the string free list looking for bogus next pointers.
1813 This may catch buffer overrun from a previous string. */
1814
1815 static void
1816 check_string_free_list ()
1817 {
1818 struct Lisp_String *s;
1819
1820 /* Pop a Lisp_String off the free-list. */
1821 s = string_free_list;
1822 while (s != NULL)
1823 {
1824 if ((unsigned)s < 1024)
1825 abort();
1826 s = NEXT_FREE_LISP_STRING (s);
1827 }
1828 }
1829 #else
1830 #define check_string_free_list()
1831 #endif
1832
1833 /* Return a new Lisp_String. */
1834
1835 static struct Lisp_String *
1836 allocate_string ()
1837 {
1838 struct Lisp_String *s;
1839
1840 /* If the free-list is empty, allocate a new string_block, and
1841 add all the Lisp_Strings in it to the free-list. */
1842 if (string_free_list == NULL)
1843 {
1844 struct string_block *b;
1845 int i;
1846
1847 b = (struct string_block *) lisp_malloc (sizeof *b, MEM_TYPE_STRING);
1848 bzero (b, sizeof *b);
1849 b->next = string_blocks;
1850 string_blocks = b;
1851 ++n_string_blocks;
1852
1853 for (i = STRING_BLOCK_SIZE - 1; i >= 0; --i)
1854 {
1855 s = b->strings + i;
1856 NEXT_FREE_LISP_STRING (s) = string_free_list;
1857 string_free_list = s;
1858 }
1859
1860 total_free_strings += STRING_BLOCK_SIZE;
1861 }
1862
1863 check_string_free_list ();
1864
1865 /* Pop a Lisp_String off the free-list. */
1866 s = string_free_list;
1867 string_free_list = NEXT_FREE_LISP_STRING (s);
1868
1869 /* Probably not strictly necessary, but play it safe. */
1870 bzero (s, sizeof *s);
1871
1872 --total_free_strings;
1873 ++total_strings;
1874 ++strings_consed;
1875 consing_since_gc += sizeof *s;
1876
1877 #ifdef GC_CHECK_STRING_BYTES
1878 if (!noninteractive
1879 #ifdef MAC_OS8
1880 && current_sblock
1881 #endif
1882 )
1883 {
1884 if (++check_string_bytes_count == 200)
1885 {
1886 check_string_bytes_count = 0;
1887 check_string_bytes (1);
1888 }
1889 else
1890 check_string_bytes (0);
1891 }
1892 #endif /* GC_CHECK_STRING_BYTES */
1893
1894 return s;
1895 }
1896
1897
1898 /* Set up Lisp_String S for holding NCHARS characters, NBYTES bytes,
1899 plus a NUL byte at the end. Allocate an sdata structure for S, and
1900 set S->data to its `u.data' member. Store a NUL byte at the end of
1901 S->data. Set S->size to NCHARS and S->size_byte to NBYTES. Free
1902 S->data if it was initially non-null. */
1903
1904 void
1905 allocate_string_data (s, nchars, nbytes)
1906 struct Lisp_String *s;
1907 int nchars, nbytes;
1908 {
1909 struct sdata *data, *old_data;
1910 struct sblock *b;
1911 int needed, old_nbytes;
1912
1913 /* Determine the number of bytes needed to store NBYTES bytes
1914 of string data. */
1915 needed = SDATA_SIZE (nbytes);
1916
1917 if (nbytes > LARGE_STRING_BYTES)
1918 {
1919 size_t size = sizeof *b - sizeof (struct sdata) + needed;
1920
1921 #ifdef DOUG_LEA_MALLOC
1922 /* Prevent mmap'ing the chunk. Lisp data may not be mmap'ed
1923 because mapped region contents are not preserved in
1924 a dumped Emacs.
1925
1926 In case you think of allowing it in a dumped Emacs at the
1927 cost of not being able to re-dump, there's another reason:
1928 mmap'ed data typically have an address towards the top of the
1929 address space, which won't fit into an EMACS_INT (at least on
1930 32-bit systems with the current tagging scheme). --fx */
1931 BLOCK_INPUT;
1932 mallopt (M_MMAP_MAX, 0);
1933 UNBLOCK_INPUT;
1934 #endif
1935
1936 b = (struct sblock *) lisp_malloc (size + GC_STRING_EXTRA, MEM_TYPE_NON_LISP);
1937
1938 #ifdef DOUG_LEA_MALLOC
1939 /* Back to a reasonable maximum of mmap'ed areas. */
1940 BLOCK_INPUT;
1941 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
1942 UNBLOCK_INPUT;
1943 #endif
1944
1945 b->next_free = &b->first_data;
1946 b->first_data.string = NULL;
1947 b->next = large_sblocks;
1948 large_sblocks = b;
1949 }
1950 else if (current_sblock == NULL
1951 || (((char *) current_sblock + SBLOCK_SIZE
1952 - (char *) current_sblock->next_free)
1953 < (needed + GC_STRING_EXTRA)))
1954 {
1955 /* Not enough room in the current sblock. */
1956 b = (struct sblock *) lisp_malloc (SBLOCK_SIZE, MEM_TYPE_NON_LISP);
1957 b->next_free = &b->first_data;
1958 b->first_data.string = NULL;
1959 b->next = NULL;
1960
1961 if (current_sblock)
1962 current_sblock->next = b;
1963 else
1964 oldest_sblock = b;
1965 current_sblock = b;
1966 }
1967 else
1968 b = current_sblock;
1969
1970 old_data = s->data ? SDATA_OF_STRING (s) : NULL;
1971 old_nbytes = GC_STRING_BYTES (s);
1972
1973 data = b->next_free;
1974 data->string = s;
1975 s->data = SDATA_DATA (data);
1976 #ifdef GC_CHECK_STRING_BYTES
1977 SDATA_NBYTES (data) = nbytes;
1978 #endif
1979 s->size = nchars;
1980 s->size_byte = nbytes;
1981 s->data[nbytes] = '\0';
1982 #ifdef GC_CHECK_STRING_OVERRUN
1983 bcopy (string_overrun_cookie, (char *) data + needed,
1984 GC_STRING_OVERRUN_COOKIE_SIZE);
1985 #endif
1986 b->next_free = (struct sdata *) ((char *) data + needed + GC_STRING_EXTRA);
1987
1988 /* If S had already data assigned, mark that as free by setting its
1989 string back-pointer to null, and recording the size of the data
1990 in it. */
1991 if (old_data)
1992 {
1993 SDATA_NBYTES (old_data) = old_nbytes;
1994 old_data->string = NULL;
1995 }
1996
1997 consing_since_gc += needed;
1998 }
1999
2000
2001 /* Sweep and compact strings. */
2002
2003 static void
2004 sweep_strings ()
2005 {
2006 struct string_block *b, *next;
2007 struct string_block *live_blocks = NULL;
2008
2009 string_free_list = NULL;
2010 total_strings = total_free_strings = 0;
2011 total_string_size = 0;
2012
2013 /* Scan strings_blocks, free Lisp_Strings that aren't marked. */
2014 for (b = string_blocks; b; b = next)
2015 {
2016 int i, nfree = 0;
2017 struct Lisp_String *free_list_before = string_free_list;
2018
2019 next = b->next;
2020
2021 for (i = 0; i < STRING_BLOCK_SIZE; ++i)
2022 {
2023 struct Lisp_String *s = b->strings + i;
2024
2025 if (s->data)
2026 {
2027 /* String was not on free-list before. */
2028 if (STRING_MARKED_P (s))
2029 {
2030 /* String is live; unmark it and its intervals. */
2031 UNMARK_STRING (s);
2032
2033 if (!NULL_INTERVAL_P (s->intervals))
2034 UNMARK_BALANCE_INTERVALS (s->intervals);
2035
2036 ++total_strings;
2037 total_string_size += STRING_BYTES (s);
2038 }
2039 else
2040 {
2041 /* String is dead. Put it on the free-list. */
2042 struct sdata *data = SDATA_OF_STRING (s);
2043
2044 /* Save the size of S in its sdata so that we know
2045 how large that is. Reset the sdata's string
2046 back-pointer so that we know it's free. */
2047 #ifdef GC_CHECK_STRING_BYTES
2048 if (GC_STRING_BYTES (s) != SDATA_NBYTES (data))
2049 abort ();
2050 #else
2051 data->u.nbytes = GC_STRING_BYTES (s);
2052 #endif
2053 data->string = NULL;
2054
2055 /* Reset the strings's `data' member so that we
2056 know it's free. */
2057 s->data = NULL;
2058
2059 /* Put the string on the free-list. */
2060 NEXT_FREE_LISP_STRING (s) = string_free_list;
2061 string_free_list = s;
2062 ++nfree;
2063 }
2064 }
2065 else
2066 {
2067 /* S was on the free-list before. Put it there again. */
2068 NEXT_FREE_LISP_STRING (s) = string_free_list;
2069 string_free_list = s;
2070 ++nfree;
2071 }
2072 }
2073
2074 /* Free blocks that contain free Lisp_Strings only, except
2075 the first two of them. */
2076 if (nfree == STRING_BLOCK_SIZE
2077 && total_free_strings > STRING_BLOCK_SIZE)
2078 {
2079 lisp_free (b);
2080 --n_string_blocks;
2081 string_free_list = free_list_before;
2082 }
2083 else
2084 {
2085 total_free_strings += nfree;
2086 b->next = live_blocks;
2087 live_blocks = b;
2088 }
2089 }
2090
2091 check_string_free_list ();
2092
2093 string_blocks = live_blocks;
2094 free_large_strings ();
2095 compact_small_strings ();
2096
2097 check_string_free_list ();
2098 }
2099
2100
2101 /* Free dead large strings. */
2102
2103 static void
2104 free_large_strings ()
2105 {
2106 struct sblock *b, *next;
2107 struct sblock *live_blocks = NULL;
2108
2109 for (b = large_sblocks; b; b = next)
2110 {
2111 next = b->next;
2112
2113 if (b->first_data.string == NULL)
2114 lisp_free (b);
2115 else
2116 {
2117 b->next = live_blocks;
2118 live_blocks = b;
2119 }
2120 }
2121
2122 large_sblocks = live_blocks;
2123 }
2124
2125
2126 /* Compact data of small strings. Free sblocks that don't contain
2127 data of live strings after compaction. */
2128
2129 static void
2130 compact_small_strings ()
2131 {
2132 struct sblock *b, *tb, *next;
2133 struct sdata *from, *to, *end, *tb_end;
2134 struct sdata *to_end, *from_end;
2135
2136 /* TB is the sblock we copy to, TO is the sdata within TB we copy
2137 to, and TB_END is the end of TB. */
2138 tb = oldest_sblock;
2139 tb_end = (struct sdata *) ((char *) tb + SBLOCK_SIZE);
2140 to = &tb->first_data;
2141
2142 /* Step through the blocks from the oldest to the youngest. We
2143 expect that old blocks will stabilize over time, so that less
2144 copying will happen this way. */
2145 for (b = oldest_sblock; b; b = b->next)
2146 {
2147 end = b->next_free;
2148 xassert ((char *) end <= (char *) b + SBLOCK_SIZE);
2149
2150 for (from = &b->first_data; from < end; from = from_end)
2151 {
2152 /* Compute the next FROM here because copying below may
2153 overwrite data we need to compute it. */
2154 int nbytes;
2155
2156 #ifdef GC_CHECK_STRING_BYTES
2157 /* Check that the string size recorded in the string is the
2158 same as the one recorded in the sdata structure. */
2159 if (from->string
2160 && GC_STRING_BYTES (from->string) != SDATA_NBYTES (from))
2161 abort ();
2162 #endif /* GC_CHECK_STRING_BYTES */
2163
2164 if (from->string)
2165 nbytes = GC_STRING_BYTES (from->string);
2166 else
2167 nbytes = SDATA_NBYTES (from);
2168
2169 if (nbytes > LARGE_STRING_BYTES)
2170 abort ();
2171
2172 nbytes = SDATA_SIZE (nbytes);
2173 from_end = (struct sdata *) ((char *) from + nbytes + GC_STRING_EXTRA);
2174
2175 #ifdef GC_CHECK_STRING_OVERRUN
2176 if (bcmp (string_overrun_cookie,
2177 ((char *) from_end) - GC_STRING_OVERRUN_COOKIE_SIZE,
2178 GC_STRING_OVERRUN_COOKIE_SIZE))
2179 abort ();
2180 #endif
2181
2182 /* FROM->string non-null means it's alive. Copy its data. */
2183 if (from->string)
2184 {
2185 /* If TB is full, proceed with the next sblock. */
2186 to_end = (struct sdata *) ((char *) to + nbytes + GC_STRING_EXTRA);
2187 if (to_end > tb_end)
2188 {
2189 tb->next_free = to;
2190 tb = tb->next;
2191 tb_end = (struct sdata *) ((char *) tb + SBLOCK_SIZE);
2192 to = &tb->first_data;
2193 to_end = (struct sdata *) ((char *) to + nbytes + GC_STRING_EXTRA);
2194 }
2195
2196 /* Copy, and update the string's `data' pointer. */
2197 if (from != to)
2198 {
2199 xassert (tb != b || to <= from);
2200 safe_bcopy ((char *) from, (char *) to, nbytes + GC_STRING_EXTRA);
2201 to->string->data = SDATA_DATA (to);
2202 }
2203
2204 /* Advance past the sdata we copied to. */
2205 to = to_end;
2206 }
2207 }
2208 }
2209
2210 /* The rest of the sblocks following TB don't contain live data, so
2211 we can free them. */
2212 for (b = tb->next; b; b = next)
2213 {
2214 next = b->next;
2215 lisp_free (b);
2216 }
2217
2218 tb->next_free = to;
2219 tb->next = NULL;
2220 current_sblock = tb;
2221 }
2222
2223
2224 DEFUN ("make-string", Fmake_string, Smake_string, 2, 2, 0,
2225 doc: /* Return a newly created string of length LENGTH, with INIT in each element.
2226 LENGTH must be an integer.
2227 INIT must be an integer that represents a character. */)
2228 (length, init)
2229 Lisp_Object length, init;
2230 {
2231 register Lisp_Object val;
2232 register unsigned char *p, *end;
2233 int c, nbytes;
2234
2235 CHECK_NATNUM (length);
2236 CHECK_NUMBER (init);
2237
2238 c = XINT (init);
2239 if (SINGLE_BYTE_CHAR_P (c))
2240 {
2241 nbytes = XINT (length);
2242 val = make_uninit_string (nbytes);
2243 p = SDATA (val);
2244 end = p + SCHARS (val);
2245 while (p != end)
2246 *p++ = c;
2247 }
2248 else
2249 {
2250 unsigned char str[MAX_MULTIBYTE_LENGTH];
2251 int len = CHAR_STRING (c, str);
2252
2253 nbytes = len * XINT (length);
2254 val = make_uninit_multibyte_string (XINT (length), nbytes);
2255 p = SDATA (val);
2256 end = p + nbytes;
2257 while (p != end)
2258 {
2259 bcopy (str, p, len);
2260 p += len;
2261 }
2262 }
2263
2264 *p = 0;
2265 return val;
2266 }
2267
2268
2269 DEFUN ("make-bool-vector", Fmake_bool_vector, Smake_bool_vector, 2, 2, 0,
2270 doc: /* Return a new bool-vector of length LENGTH, using INIT for as each element.
2271 LENGTH must be a number. INIT matters only in whether it is t or nil. */)
2272 (length, init)
2273 Lisp_Object length, init;
2274 {
2275 register Lisp_Object val;
2276 struct Lisp_Bool_Vector *p;
2277 int real_init, i;
2278 int length_in_chars, length_in_elts, bits_per_value;
2279
2280 CHECK_NATNUM (length);
2281
2282 bits_per_value = sizeof (EMACS_INT) * BOOL_VECTOR_BITS_PER_CHAR;
2283
2284 length_in_elts = (XFASTINT (length) + bits_per_value - 1) / bits_per_value;
2285 length_in_chars = ((XFASTINT (length) + BOOL_VECTOR_BITS_PER_CHAR - 1)
2286 / BOOL_VECTOR_BITS_PER_CHAR);
2287
2288 /* We must allocate one more elements than LENGTH_IN_ELTS for the
2289 slot `size' of the struct Lisp_Bool_Vector. */
2290 val = Fmake_vector (make_number (length_in_elts + 1), Qnil);
2291 p = XBOOL_VECTOR (val);
2292
2293 /* Get rid of any bits that would cause confusion. */
2294 p->vector_size = 0;
2295 XSETBOOL_VECTOR (val, p);
2296 p->size = XFASTINT (length);
2297
2298 real_init = (NILP (init) ? 0 : -1);
2299 for (i = 0; i < length_in_chars ; i++)
2300 p->data[i] = real_init;
2301
2302 /* Clear the extraneous bits in the last byte. */
2303 if (XINT (length) != length_in_chars * BOOL_VECTOR_BITS_PER_CHAR)
2304 XBOOL_VECTOR (val)->data[length_in_chars - 1]
2305 &= (1 << (XINT (length) % BOOL_VECTOR_BITS_PER_CHAR)) - 1;
2306
2307 return val;
2308 }
2309
2310
2311 /* Make a string from NBYTES bytes at CONTENTS, and compute the number
2312 of characters from the contents. This string may be unibyte or
2313 multibyte, depending on the contents. */
2314
2315 Lisp_Object
2316 make_string (contents, nbytes)
2317 const char *contents;
2318 int nbytes;
2319 {
2320 register Lisp_Object val;
2321 int nchars, multibyte_nbytes;
2322
2323 parse_str_as_multibyte (contents, nbytes, &nchars, &multibyte_nbytes);
2324 if (nbytes == nchars || nbytes != multibyte_nbytes)
2325 /* CONTENTS contains no multibyte sequences or contains an invalid
2326 multibyte sequence. We must make unibyte string. */
2327 val = make_unibyte_string (contents, nbytes);
2328 else
2329 val = make_multibyte_string (contents, nchars, nbytes);
2330 return val;
2331 }
2332
2333
2334 /* Make an unibyte string from LENGTH bytes at CONTENTS. */
2335
2336 Lisp_Object
2337 make_unibyte_string (contents, length)
2338 const char *contents;
2339 int length;
2340 {
2341 register Lisp_Object val;
2342 val = make_uninit_string (length);
2343 bcopy (contents, SDATA (val), length);
2344 STRING_SET_UNIBYTE (val);
2345 return val;
2346 }
2347
2348
2349 /* Make a multibyte string from NCHARS characters occupying NBYTES
2350 bytes at CONTENTS. */
2351
2352 Lisp_Object
2353 make_multibyte_string (contents, nchars, nbytes)
2354 const char *contents;
2355 int nchars, nbytes;
2356 {
2357 register Lisp_Object val;
2358 val = make_uninit_multibyte_string (nchars, nbytes);
2359 bcopy (contents, SDATA (val), nbytes);
2360 return val;
2361 }
2362
2363
2364 /* Make a string from NCHARS characters occupying NBYTES bytes at
2365 CONTENTS. It is a multibyte string if NBYTES != NCHARS. */
2366
2367 Lisp_Object
2368 make_string_from_bytes (contents, nchars, nbytes)
2369 const char *contents;
2370 int nchars, nbytes;
2371 {
2372 register Lisp_Object val;
2373 val = make_uninit_multibyte_string (nchars, nbytes);
2374 bcopy (contents, SDATA (val), nbytes);
2375 if (SBYTES (val) == SCHARS (val))
2376 STRING_SET_UNIBYTE (val);
2377 return val;
2378 }
2379
2380
2381 /* Make a string from NCHARS characters occupying NBYTES bytes at
2382 CONTENTS. The argument MULTIBYTE controls whether to label the
2383 string as multibyte. If NCHARS is negative, it counts the number of
2384 characters by itself. */
2385
2386 Lisp_Object
2387 make_specified_string (contents, nchars, nbytes, multibyte)
2388 const char *contents;
2389 int nchars, nbytes;
2390 int multibyte;
2391 {
2392 register Lisp_Object val;
2393
2394 if (nchars < 0)
2395 {
2396 if (multibyte)
2397 nchars = multibyte_chars_in_text (contents, nbytes);
2398 else
2399 nchars = nbytes;
2400 }
2401 val = make_uninit_multibyte_string (nchars, nbytes);
2402 bcopy (contents, SDATA (val), nbytes);
2403 if (!multibyte)
2404 STRING_SET_UNIBYTE (val);
2405 return val;
2406 }
2407
2408
2409 /* Make a string from the data at STR, treating it as multibyte if the
2410 data warrants. */
2411
2412 Lisp_Object
2413 build_string (str)
2414 const char *str;
2415 {
2416 return make_string (str, strlen (str));
2417 }
2418
2419
2420 /* Return an unibyte Lisp_String set up to hold LENGTH characters
2421 occupying LENGTH bytes. */
2422
2423 Lisp_Object
2424 make_uninit_string (length)
2425 int length;
2426 {
2427 Lisp_Object val;
2428 val = make_uninit_multibyte_string (length, length);
2429 STRING_SET_UNIBYTE (val);
2430 return val;
2431 }
2432
2433
2434 /* Return a multibyte Lisp_String set up to hold NCHARS characters
2435 which occupy NBYTES bytes. */
2436
2437 Lisp_Object
2438 make_uninit_multibyte_string (nchars, nbytes)
2439 int nchars, nbytes;
2440 {
2441 Lisp_Object string;
2442 struct Lisp_String *s;
2443
2444 if (nchars < 0)
2445 abort ();
2446
2447 s = allocate_string ();
2448 allocate_string_data (s, nchars, nbytes);
2449 XSETSTRING (string, s);
2450 string_chars_consed += nbytes;
2451 return string;
2452 }
2453
2454
2455 \f
2456 /***********************************************************************
2457 Float Allocation
2458 ***********************************************************************/
2459
2460 /* We store float cells inside of float_blocks, allocating a new
2461 float_block with malloc whenever necessary. Float cells reclaimed
2462 by GC are put on a free list to be reallocated before allocating
2463 any new float cells from the latest float_block. */
2464
2465 #define FLOAT_BLOCK_SIZE \
2466 (((BLOCK_BYTES - sizeof (struct float_block *) \
2467 /* The compiler might add padding at the end. */ \
2468 - (sizeof (struct Lisp_Float) - sizeof (int))) * CHAR_BIT) \
2469 / (sizeof (struct Lisp_Float) * CHAR_BIT + 1))
2470
2471 #define GETMARKBIT(block,n) \
2472 (((block)->gcmarkbits[(n) / (sizeof(int) * CHAR_BIT)] \
2473 >> ((n) % (sizeof(int) * CHAR_BIT))) \
2474 & 1)
2475
2476 #define SETMARKBIT(block,n) \
2477 (block)->gcmarkbits[(n) / (sizeof(int) * CHAR_BIT)] \
2478 |= 1 << ((n) % (sizeof(int) * CHAR_BIT))
2479
2480 #define UNSETMARKBIT(block,n) \
2481 (block)->gcmarkbits[(n) / (sizeof(int) * CHAR_BIT)] \
2482 &= ~(1 << ((n) % (sizeof(int) * CHAR_BIT)))
2483
2484 #define FLOAT_BLOCK(fptr) \
2485 ((struct float_block *)(((EMACS_UINT)(fptr)) & ~(BLOCK_ALIGN - 1)))
2486
2487 #define FLOAT_INDEX(fptr) \
2488 ((((EMACS_UINT)(fptr)) & (BLOCK_ALIGN - 1)) / sizeof (struct Lisp_Float))
2489
2490 struct float_block
2491 {
2492 /* Place `floats' at the beginning, to ease up FLOAT_INDEX's job. */
2493 struct Lisp_Float floats[FLOAT_BLOCK_SIZE];
2494 int gcmarkbits[1 + FLOAT_BLOCK_SIZE / (sizeof(int) * CHAR_BIT)];
2495 struct float_block *next;
2496 };
2497
2498 #define FLOAT_MARKED_P(fptr) \
2499 GETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr)))
2500
2501 #define FLOAT_MARK(fptr) \
2502 SETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr)))
2503
2504 #define FLOAT_UNMARK(fptr) \
2505 UNSETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr)))
2506
2507 /* Current float_block. */
2508
2509 struct float_block *float_block;
2510
2511 /* Index of first unused Lisp_Float in the current float_block. */
2512
2513 int float_block_index;
2514
2515 /* Total number of float blocks now in use. */
2516
2517 int n_float_blocks;
2518
2519 /* Free-list of Lisp_Floats. */
2520
2521 struct Lisp_Float *float_free_list;
2522
2523
2524 /* Initialize float allocation. */
2525
2526 void
2527 init_float ()
2528 {
2529 float_block = NULL;
2530 float_block_index = FLOAT_BLOCK_SIZE; /* Force alloc of new float_block. */
2531 float_free_list = 0;
2532 n_float_blocks = 0;
2533 }
2534
2535
2536 /* Explicitly free a float cell by putting it on the free-list. */
2537
2538 void
2539 free_float (ptr)
2540 struct Lisp_Float *ptr;
2541 {
2542 ptr->u.chain = float_free_list;
2543 float_free_list = ptr;
2544 }
2545
2546
2547 /* Return a new float object with value FLOAT_VALUE. */
2548
2549 Lisp_Object
2550 make_float (float_value)
2551 double float_value;
2552 {
2553 register Lisp_Object val;
2554
2555 if (float_free_list)
2556 {
2557 /* We use the data field for chaining the free list
2558 so that we won't use the same field that has the mark bit. */
2559 XSETFLOAT (val, float_free_list);
2560 float_free_list = float_free_list->u.chain;
2561 }
2562 else
2563 {
2564 if (float_block_index == FLOAT_BLOCK_SIZE)
2565 {
2566 register struct float_block *new;
2567
2568 new = (struct float_block *) lisp_align_malloc (sizeof *new,
2569 MEM_TYPE_FLOAT);
2570 new->next = float_block;
2571 bzero ((char *) new->gcmarkbits, sizeof new->gcmarkbits);
2572 float_block = new;
2573 float_block_index = 0;
2574 n_float_blocks++;
2575 }
2576 XSETFLOAT (val, &float_block->floats[float_block_index]);
2577 float_block_index++;
2578 }
2579
2580 XFLOAT_DATA (val) = float_value;
2581 eassert (!FLOAT_MARKED_P (XFLOAT (val)));
2582 consing_since_gc += sizeof (struct Lisp_Float);
2583 floats_consed++;
2584 return val;
2585 }
2586
2587
2588 \f
2589 /***********************************************************************
2590 Cons Allocation
2591 ***********************************************************************/
2592
2593 /* We store cons cells inside of cons_blocks, allocating a new
2594 cons_block with malloc whenever necessary. Cons cells reclaimed by
2595 GC are put on a free list to be reallocated before allocating
2596 any new cons cells from the latest cons_block. */
2597
2598 #define CONS_BLOCK_SIZE \
2599 (((BLOCK_BYTES - sizeof (struct cons_block *)) * CHAR_BIT) \
2600 / (sizeof (struct Lisp_Cons) * CHAR_BIT + 1))
2601
2602 #define CONS_BLOCK(fptr) \
2603 ((struct cons_block *)(((EMACS_UINT)(fptr)) & ~(BLOCK_ALIGN - 1)))
2604
2605 #define CONS_INDEX(fptr) \
2606 ((((EMACS_UINT)(fptr)) & (BLOCK_ALIGN - 1)) / sizeof (struct Lisp_Cons))
2607
2608 struct cons_block
2609 {
2610 /* Place `conses' at the beginning, to ease up CONS_INDEX's job. */
2611 struct Lisp_Cons conses[CONS_BLOCK_SIZE];
2612 int gcmarkbits[1 + CONS_BLOCK_SIZE / (sizeof(int) * CHAR_BIT)];
2613 struct cons_block *next;
2614 };
2615
2616 #define CONS_MARKED_P(fptr) \
2617 GETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr)))
2618
2619 #define CONS_MARK(fptr) \
2620 SETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr)))
2621
2622 #define CONS_UNMARK(fptr) \
2623 UNSETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr)))
2624
2625 /* Current cons_block. */
2626
2627 struct cons_block *cons_block;
2628
2629 /* Index of first unused Lisp_Cons in the current block. */
2630
2631 int cons_block_index;
2632
2633 /* Free-list of Lisp_Cons structures. */
2634
2635 struct Lisp_Cons *cons_free_list;
2636
2637 /* Total number of cons blocks now in use. */
2638
2639 int n_cons_blocks;
2640
2641
2642 /* Initialize cons allocation. */
2643
2644 void
2645 init_cons ()
2646 {
2647 cons_block = NULL;
2648 cons_block_index = CONS_BLOCK_SIZE; /* Force alloc of new cons_block. */
2649 cons_free_list = 0;
2650 n_cons_blocks = 0;
2651 }
2652
2653
2654 /* Explicitly free a cons cell by putting it on the free-list. */
2655
2656 void
2657 free_cons (ptr)
2658 struct Lisp_Cons *ptr;
2659 {
2660 ptr->u.chain = cons_free_list;
2661 #if GC_MARK_STACK
2662 ptr->car = Vdead;
2663 #endif
2664 cons_free_list = ptr;
2665 }
2666
2667 DEFUN ("cons", Fcons, Scons, 2, 2, 0,
2668 doc: /* Create a new cons, give it CAR and CDR as components, and return it. */)
2669 (car, cdr)
2670 Lisp_Object car, cdr;
2671 {
2672 register Lisp_Object val;
2673
2674 if (cons_free_list)
2675 {
2676 /* We use the cdr for chaining the free list
2677 so that we won't use the same field that has the mark bit. */
2678 XSETCONS (val, cons_free_list);
2679 cons_free_list = cons_free_list->u.chain;
2680 }
2681 else
2682 {
2683 if (cons_block_index == CONS_BLOCK_SIZE)
2684 {
2685 register struct cons_block *new;
2686 new = (struct cons_block *) lisp_align_malloc (sizeof *new,
2687 MEM_TYPE_CONS);
2688 bzero ((char *) new->gcmarkbits, sizeof new->gcmarkbits);
2689 new->next = cons_block;
2690 cons_block = new;
2691 cons_block_index = 0;
2692 n_cons_blocks++;
2693 }
2694 XSETCONS (val, &cons_block->conses[cons_block_index]);
2695 cons_block_index++;
2696 }
2697
2698 XSETCAR (val, car);
2699 XSETCDR (val, cdr);
2700 eassert (!CONS_MARKED_P (XCONS (val)));
2701 consing_since_gc += sizeof (struct Lisp_Cons);
2702 cons_cells_consed++;
2703 return val;
2704 }
2705
2706 /* Get an error now if there's any junk in the cons free list. */
2707 void
2708 check_cons_list ()
2709 {
2710 #ifdef GC_CHECK_CONS_LIST
2711 struct Lisp_Cons *tail = cons_free_list;
2712
2713 while (tail)
2714 tail = tail->u.chain;
2715 #endif
2716 }
2717
2718 /* Make a list of 2, 3, 4 or 5 specified objects. */
2719
2720 Lisp_Object
2721 list2 (arg1, arg2)
2722 Lisp_Object arg1, arg2;
2723 {
2724 return Fcons (arg1, Fcons (arg2, Qnil));
2725 }
2726
2727
2728 Lisp_Object
2729 list3 (arg1, arg2, arg3)
2730 Lisp_Object arg1, arg2, arg3;
2731 {
2732 return Fcons (arg1, Fcons (arg2, Fcons (arg3, Qnil)));
2733 }
2734
2735
2736 Lisp_Object
2737 list4 (arg1, arg2, arg3, arg4)
2738 Lisp_Object arg1, arg2, arg3, arg4;
2739 {
2740 return Fcons (arg1, Fcons (arg2, Fcons (arg3, Fcons (arg4, Qnil))));
2741 }
2742
2743
2744 Lisp_Object
2745 list5 (arg1, arg2, arg3, arg4, arg5)
2746 Lisp_Object arg1, arg2, arg3, arg4, arg5;
2747 {
2748 return Fcons (arg1, Fcons (arg2, Fcons (arg3, Fcons (arg4,
2749 Fcons (arg5, Qnil)))));
2750 }
2751
2752
2753 DEFUN ("list", Flist, Slist, 0, MANY, 0,
2754 doc: /* Return a newly created list with specified arguments as elements.
2755 Any number of arguments, even zero arguments, are allowed.
2756 usage: (list &rest OBJECTS) */)
2757 (nargs, args)
2758 int nargs;
2759 register Lisp_Object *args;
2760 {
2761 register Lisp_Object val;
2762 val = Qnil;
2763
2764 while (nargs > 0)
2765 {
2766 nargs--;
2767 val = Fcons (args[nargs], val);
2768 }
2769 return val;
2770 }
2771
2772
2773 DEFUN ("make-list", Fmake_list, Smake_list, 2, 2, 0,
2774 doc: /* Return a newly created list of length LENGTH, with each element being INIT. */)
2775 (length, init)
2776 register Lisp_Object length, init;
2777 {
2778 register Lisp_Object val;
2779 register int size;
2780
2781 CHECK_NATNUM (length);
2782 size = XFASTINT (length);
2783
2784 val = Qnil;
2785 while (size > 0)
2786 {
2787 val = Fcons (init, val);
2788 --size;
2789
2790 if (size > 0)
2791 {
2792 val = Fcons (init, val);
2793 --size;
2794
2795 if (size > 0)
2796 {
2797 val = Fcons (init, val);
2798 --size;
2799
2800 if (size > 0)
2801 {
2802 val = Fcons (init, val);
2803 --size;
2804
2805 if (size > 0)
2806 {
2807 val = Fcons (init, val);
2808 --size;
2809 }
2810 }
2811 }
2812 }
2813
2814 QUIT;
2815 }
2816
2817 return val;
2818 }
2819
2820
2821 \f
2822 /***********************************************************************
2823 Vector Allocation
2824 ***********************************************************************/
2825
2826 /* Singly-linked list of all vectors. */
2827
2828 struct Lisp_Vector *all_vectors;
2829
2830 /* Total number of vector-like objects now in use. */
2831
2832 int n_vectors;
2833
2834
2835 /* Value is a pointer to a newly allocated Lisp_Vector structure
2836 with room for LEN Lisp_Objects. */
2837
2838 static struct Lisp_Vector *
2839 allocate_vectorlike (len, type)
2840 EMACS_INT len;
2841 enum mem_type type;
2842 {
2843 struct Lisp_Vector *p;
2844 size_t nbytes;
2845
2846 #ifdef DOUG_LEA_MALLOC
2847 /* Prevent mmap'ing the chunk. Lisp data may not be mmap'ed
2848 because mapped region contents are not preserved in
2849 a dumped Emacs. */
2850 BLOCK_INPUT;
2851 mallopt (M_MMAP_MAX, 0);
2852 UNBLOCK_INPUT;
2853 #endif
2854
2855 nbytes = sizeof *p + (len - 1) * sizeof p->contents[0];
2856 p = (struct Lisp_Vector *) lisp_malloc (nbytes, type);
2857
2858 #ifdef DOUG_LEA_MALLOC
2859 /* Back to a reasonable maximum of mmap'ed areas. */
2860 BLOCK_INPUT;
2861 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
2862 UNBLOCK_INPUT;
2863 #endif
2864
2865 consing_since_gc += nbytes;
2866 vector_cells_consed += len;
2867
2868 p->next = all_vectors;
2869 all_vectors = p;
2870 ++n_vectors;
2871 return p;
2872 }
2873
2874
2875 /* Allocate a vector with NSLOTS slots. */
2876
2877 struct Lisp_Vector *
2878 allocate_vector (nslots)
2879 EMACS_INT nslots;
2880 {
2881 struct Lisp_Vector *v = allocate_vectorlike (nslots, MEM_TYPE_VECTOR);
2882 v->size = nslots;
2883 return v;
2884 }
2885
2886
2887 /* Allocate other vector-like structures. */
2888
2889 struct Lisp_Hash_Table *
2890 allocate_hash_table ()
2891 {
2892 EMACS_INT len = VECSIZE (struct Lisp_Hash_Table);
2893 struct Lisp_Vector *v = allocate_vectorlike (len, MEM_TYPE_HASH_TABLE);
2894 EMACS_INT i;
2895
2896 v->size = len;
2897 for (i = 0; i < len; ++i)
2898 v->contents[i] = Qnil;
2899
2900 return (struct Lisp_Hash_Table *) v;
2901 }
2902
2903
2904 struct window *
2905 allocate_window ()
2906 {
2907 EMACS_INT len = VECSIZE (struct window);
2908 struct Lisp_Vector *v = allocate_vectorlike (len, MEM_TYPE_WINDOW);
2909 EMACS_INT i;
2910
2911 for (i = 0; i < len; ++i)
2912 v->contents[i] = Qnil;
2913 v->size = len;
2914
2915 return (struct window *) v;
2916 }
2917
2918
2919 struct frame *
2920 allocate_frame ()
2921 {
2922 EMACS_INT len = VECSIZE (struct frame);
2923 struct Lisp_Vector *v = allocate_vectorlike (len, MEM_TYPE_FRAME);
2924 EMACS_INT i;
2925
2926 for (i = 0; i < len; ++i)
2927 v->contents[i] = make_number (0);
2928 v->size = len;
2929 return (struct frame *) v;
2930 }
2931
2932
2933 struct Lisp_Process *
2934 allocate_process ()
2935 {
2936 EMACS_INT len = VECSIZE (struct Lisp_Process);
2937 struct Lisp_Vector *v = allocate_vectorlike (len, MEM_TYPE_PROCESS);
2938 EMACS_INT i;
2939
2940 for (i = 0; i < len; ++i)
2941 v->contents[i] = Qnil;
2942 v->size = len;
2943
2944 return (struct Lisp_Process *) v;
2945 }
2946
2947
2948 struct Lisp_Vector *
2949 allocate_other_vector (len)
2950 EMACS_INT len;
2951 {
2952 struct Lisp_Vector *v = allocate_vectorlike (len, MEM_TYPE_VECTOR);
2953 EMACS_INT i;
2954
2955 for (i = 0; i < len; ++i)
2956 v->contents[i] = Qnil;
2957 v->size = len;
2958
2959 return v;
2960 }
2961
2962
2963 DEFUN ("make-vector", Fmake_vector, Smake_vector, 2, 2, 0,
2964 doc: /* Return a newly created vector of length LENGTH, with each element being INIT.
2965 See also the function `vector'. */)
2966 (length, init)
2967 register Lisp_Object length, init;
2968 {
2969 Lisp_Object vector;
2970 register EMACS_INT sizei;
2971 register int index;
2972 register struct Lisp_Vector *p;
2973
2974 CHECK_NATNUM (length);
2975 sizei = XFASTINT (length);
2976
2977 p = allocate_vector (sizei);
2978 for (index = 0; index < sizei; index++)
2979 p->contents[index] = init;
2980
2981 XSETVECTOR (vector, p);
2982 return vector;
2983 }
2984
2985
2986 DEFUN ("make-char-table", Fmake_char_table, Smake_char_table, 1, 2, 0,
2987 doc: /* Return a newly created char-table, with purpose PURPOSE.
2988 Each element is initialized to INIT, which defaults to nil.
2989 PURPOSE should be a symbol which has a `char-table-extra-slots' property.
2990 The property's value should be an integer between 0 and 10. */)
2991 (purpose, init)
2992 register Lisp_Object purpose, init;
2993 {
2994 Lisp_Object vector;
2995 Lisp_Object n;
2996 CHECK_SYMBOL (purpose);
2997 n = Fget (purpose, Qchar_table_extra_slots);
2998 CHECK_NUMBER (n);
2999 if (XINT (n) < 0 || XINT (n) > 10)
3000 args_out_of_range (n, Qnil);
3001 /* Add 2 to the size for the defalt and parent slots. */
3002 vector = Fmake_vector (make_number (CHAR_TABLE_STANDARD_SLOTS + XINT (n)),
3003 init);
3004 XCHAR_TABLE (vector)->top = Qt;
3005 XCHAR_TABLE (vector)->parent = Qnil;
3006 XCHAR_TABLE (vector)->purpose = purpose;
3007 XSETCHAR_TABLE (vector, XCHAR_TABLE (vector));
3008 return vector;
3009 }
3010
3011
3012 /* Return a newly created sub char table with slots initialized by INIT.
3013 Since a sub char table does not appear as a top level Emacs Lisp
3014 object, we don't need a Lisp interface to make it. */
3015
3016 Lisp_Object
3017 make_sub_char_table (init)
3018 Lisp_Object init;
3019 {
3020 Lisp_Object vector
3021 = Fmake_vector (make_number (SUB_CHAR_TABLE_STANDARD_SLOTS), init);
3022 XCHAR_TABLE (vector)->top = Qnil;
3023 XCHAR_TABLE (vector)->defalt = Qnil;
3024 XSETCHAR_TABLE (vector, XCHAR_TABLE (vector));
3025 return vector;
3026 }
3027
3028
3029 DEFUN ("vector", Fvector, Svector, 0, MANY, 0,
3030 doc: /* Return a newly created vector with specified arguments as elements.
3031 Any number of arguments, even zero arguments, are allowed.
3032 usage: (vector &rest OBJECTS) */)
3033 (nargs, args)
3034 register int nargs;
3035 Lisp_Object *args;
3036 {
3037 register Lisp_Object len, val;
3038 register int index;
3039 register struct Lisp_Vector *p;
3040
3041 XSETFASTINT (len, nargs);
3042 val = Fmake_vector (len, Qnil);
3043 p = XVECTOR (val);
3044 for (index = 0; index < nargs; index++)
3045 p->contents[index] = args[index];
3046 return val;
3047 }
3048
3049
3050 DEFUN ("make-byte-code", Fmake_byte_code, Smake_byte_code, 4, MANY, 0,
3051 doc: /* Create a byte-code object with specified arguments as elements.
3052 The arguments should be the arglist, bytecode-string, constant vector,
3053 stack size, (optional) doc string, and (optional) interactive spec.
3054 The first four arguments are required; at most six have any
3055 significance.
3056 usage: (make-byte-code ARGLIST BYTE-CODE CONSTANTS DEPTH &optional DOCSTRING INTERACTIVE-SPEC &rest ELEMENTS) */)
3057 (nargs, args)
3058 register int nargs;
3059 Lisp_Object *args;
3060 {
3061 register Lisp_Object len, val;
3062 register int index;
3063 register struct Lisp_Vector *p;
3064
3065 XSETFASTINT (len, nargs);
3066 if (!NILP (Vpurify_flag))
3067 val = make_pure_vector ((EMACS_INT) nargs);
3068 else
3069 val = Fmake_vector (len, Qnil);
3070
3071 if (STRINGP (args[1]) && STRING_MULTIBYTE (args[1]))
3072 /* BYTECODE-STRING must have been produced by Emacs 20.2 or the
3073 earlier because they produced a raw 8-bit string for byte-code
3074 and now such a byte-code string is loaded as multibyte while
3075 raw 8-bit characters converted to multibyte form. Thus, now we
3076 must convert them back to the original unibyte form. */
3077 args[1] = Fstring_as_unibyte (args[1]);
3078
3079 p = XVECTOR (val);
3080 for (index = 0; index < nargs; index++)
3081 {
3082 if (!NILP (Vpurify_flag))
3083 args[index] = Fpurecopy (args[index]);
3084 p->contents[index] = args[index];
3085 }
3086 XSETCOMPILED (val, p);
3087 return val;
3088 }
3089
3090
3091 \f
3092 /***********************************************************************
3093 Symbol Allocation
3094 ***********************************************************************/
3095
3096 /* Each symbol_block is just under 1020 bytes long, since malloc
3097 really allocates in units of powers of two and uses 4 bytes for its
3098 own overhead. */
3099
3100 #define SYMBOL_BLOCK_SIZE \
3101 ((1020 - sizeof (struct symbol_block *)) / sizeof (struct Lisp_Symbol))
3102
3103 struct symbol_block
3104 {
3105 /* Place `symbols' first, to preserve alignment. */
3106 struct Lisp_Symbol symbols[SYMBOL_BLOCK_SIZE];
3107 struct symbol_block *next;
3108 };
3109
3110 /* Current symbol block and index of first unused Lisp_Symbol
3111 structure in it. */
3112
3113 struct symbol_block *symbol_block;
3114 int symbol_block_index;
3115
3116 /* List of free symbols. */
3117
3118 struct Lisp_Symbol *symbol_free_list;
3119
3120 /* Total number of symbol blocks now in use. */
3121
3122 int n_symbol_blocks;
3123
3124
3125 /* Initialize symbol allocation. */
3126
3127 void
3128 init_symbol ()
3129 {
3130 symbol_block = NULL;
3131 symbol_block_index = SYMBOL_BLOCK_SIZE;
3132 symbol_free_list = 0;
3133 n_symbol_blocks = 0;
3134 }
3135
3136
3137 DEFUN ("make-symbol", Fmake_symbol, Smake_symbol, 1, 1, 0,
3138 doc: /* Return a newly allocated uninterned symbol whose name is NAME.
3139 Its value and function definition are void, and its property list is nil. */)
3140 (name)
3141 Lisp_Object name;
3142 {
3143 register Lisp_Object val;
3144 register struct Lisp_Symbol *p;
3145
3146 CHECK_STRING (name);
3147
3148 if (symbol_free_list)
3149 {
3150 XSETSYMBOL (val, symbol_free_list);
3151 symbol_free_list = symbol_free_list->next;
3152 }
3153 else
3154 {
3155 if (symbol_block_index == SYMBOL_BLOCK_SIZE)
3156 {
3157 struct symbol_block *new;
3158 new = (struct symbol_block *) lisp_malloc (sizeof *new,
3159 MEM_TYPE_SYMBOL);
3160 new->next = symbol_block;
3161 symbol_block = new;
3162 symbol_block_index = 0;
3163 n_symbol_blocks++;
3164 }
3165 XSETSYMBOL (val, &symbol_block->symbols[symbol_block_index]);
3166 symbol_block_index++;
3167 }
3168
3169 p = XSYMBOL (val);
3170 p->xname = name;
3171 p->plist = Qnil;
3172 p->value = Qunbound;
3173 p->function = Qunbound;
3174 p->next = NULL;
3175 p->gcmarkbit = 0;
3176 p->interned = SYMBOL_UNINTERNED;
3177 p->constant = 0;
3178 p->indirect_variable = 0;
3179 consing_since_gc += sizeof (struct Lisp_Symbol);
3180 symbols_consed++;
3181 return val;
3182 }
3183
3184
3185 \f
3186 /***********************************************************************
3187 Marker (Misc) Allocation
3188 ***********************************************************************/
3189
3190 /* Allocation of markers and other objects that share that structure.
3191 Works like allocation of conses. */
3192
3193 #define MARKER_BLOCK_SIZE \
3194 ((1020 - sizeof (struct marker_block *)) / sizeof (union Lisp_Misc))
3195
3196 struct marker_block
3197 {
3198 /* Place `markers' first, to preserve alignment. */
3199 union Lisp_Misc markers[MARKER_BLOCK_SIZE];
3200 struct marker_block *next;
3201 };
3202
3203 struct marker_block *marker_block;
3204 int marker_block_index;
3205
3206 union Lisp_Misc *marker_free_list;
3207
3208 /* Total number of marker blocks now in use. */
3209
3210 int n_marker_blocks;
3211
3212 void
3213 init_marker ()
3214 {
3215 marker_block = NULL;
3216 marker_block_index = MARKER_BLOCK_SIZE;
3217 marker_free_list = 0;
3218 n_marker_blocks = 0;
3219 }
3220
3221 /* Return a newly allocated Lisp_Misc object, with no substructure. */
3222
3223 Lisp_Object
3224 allocate_misc ()
3225 {
3226 Lisp_Object val;
3227
3228 if (marker_free_list)
3229 {
3230 XSETMISC (val, marker_free_list);
3231 marker_free_list = marker_free_list->u_free.chain;
3232 }
3233 else
3234 {
3235 if (marker_block_index == MARKER_BLOCK_SIZE)
3236 {
3237 struct marker_block *new;
3238 new = (struct marker_block *) lisp_malloc (sizeof *new,
3239 MEM_TYPE_MISC);
3240 new->next = marker_block;
3241 marker_block = new;
3242 marker_block_index = 0;
3243 n_marker_blocks++;
3244 total_free_markers += MARKER_BLOCK_SIZE;
3245 }
3246 XSETMISC (val, &marker_block->markers[marker_block_index]);
3247 marker_block_index++;
3248 }
3249
3250 --total_free_markers;
3251 consing_since_gc += sizeof (union Lisp_Misc);
3252 misc_objects_consed++;
3253 XMARKER (val)->gcmarkbit = 0;
3254 return val;
3255 }
3256
3257 /* Free a Lisp_Misc object */
3258
3259 void
3260 free_misc (misc)
3261 Lisp_Object misc;
3262 {
3263 XMISC (misc)->u_marker.type = Lisp_Misc_Free;
3264 XMISC (misc)->u_free.chain = marker_free_list;
3265 marker_free_list = XMISC (misc);
3266
3267 total_free_markers++;
3268 }
3269
3270 /* Return a Lisp_Misc_Save_Value object containing POINTER and
3271 INTEGER. This is used to package C values to call record_unwind_protect.
3272 The unwind function can get the C values back using XSAVE_VALUE. */
3273
3274 Lisp_Object
3275 make_save_value (pointer, integer)
3276 void *pointer;
3277 int integer;
3278 {
3279 register Lisp_Object val;
3280 register struct Lisp_Save_Value *p;
3281
3282 val = allocate_misc ();
3283 XMISCTYPE (val) = Lisp_Misc_Save_Value;
3284 p = XSAVE_VALUE (val);
3285 p->pointer = pointer;
3286 p->integer = integer;
3287 p->dogc = 0;
3288 return val;
3289 }
3290
3291 DEFUN ("make-marker", Fmake_marker, Smake_marker, 0, 0, 0,
3292 doc: /* Return a newly allocated marker which does not point at any place. */)
3293 ()
3294 {
3295 register Lisp_Object val;
3296 register struct Lisp_Marker *p;
3297
3298 val = allocate_misc ();
3299 XMISCTYPE (val) = Lisp_Misc_Marker;
3300 p = XMARKER (val);
3301 p->buffer = 0;
3302 p->bytepos = 0;
3303 p->charpos = 0;
3304 p->next = NULL;
3305 p->insertion_type = 0;
3306 return val;
3307 }
3308
3309 /* Put MARKER back on the free list after using it temporarily. */
3310
3311 void
3312 free_marker (marker)
3313 Lisp_Object marker;
3314 {
3315 unchain_marker (XMARKER (marker));
3316 free_misc (marker);
3317 }
3318
3319 \f
3320 /* Return a newly created vector or string with specified arguments as
3321 elements. If all the arguments are characters that can fit
3322 in a string of events, make a string; otherwise, make a vector.
3323
3324 Any number of arguments, even zero arguments, are allowed. */
3325
3326 Lisp_Object
3327 make_event_array (nargs, args)
3328 register int nargs;
3329 Lisp_Object *args;
3330 {
3331 int i;
3332
3333 for (i = 0; i < nargs; i++)
3334 /* The things that fit in a string
3335 are characters that are in 0...127,
3336 after discarding the meta bit and all the bits above it. */
3337 if (!INTEGERP (args[i])
3338 || (XUINT (args[i]) & ~(-CHAR_META)) >= 0200)
3339 return Fvector (nargs, args);
3340
3341 /* Since the loop exited, we know that all the things in it are
3342 characters, so we can make a string. */
3343 {
3344 Lisp_Object result;
3345
3346 result = Fmake_string (make_number (nargs), make_number (0));
3347 for (i = 0; i < nargs; i++)
3348 {
3349 SSET (result, i, XINT (args[i]));
3350 /* Move the meta bit to the right place for a string char. */
3351 if (XINT (args[i]) & CHAR_META)
3352 SSET (result, i, SREF (result, i) | 0x80);
3353 }
3354
3355 return result;
3356 }
3357 }
3358
3359
3360 \f
3361 /************************************************************************
3362 Memory Full Handling
3363 ************************************************************************/
3364
3365
3366 /* Called if malloc returns zero. */
3367
3368 void
3369 memory_full ()
3370 {
3371 int i;
3372
3373 Vmemory_full = Qt;
3374
3375 memory_full_cons_threshold = sizeof (struct cons_block);
3376
3377 /* The first time we get here, free the spare memory. */
3378 for (i = 0; i < sizeof (spare_memory) / sizeof (char *); i++)
3379 if (spare_memory[i])
3380 {
3381 if (i == 0)
3382 free (spare_memory[i]);
3383 else if (i >= 1 && i <= 4)
3384 lisp_align_free (spare_memory[i]);
3385 else
3386 lisp_free (spare_memory[i]);
3387 spare_memory[i] = 0;
3388 }
3389
3390 /* Record the space now used. When it decreases substantially,
3391 we can refill the memory reserve. */
3392 #ifndef SYSTEM_MALLOC
3393 bytes_used_when_full = BYTES_USED;
3394 #endif
3395
3396 /* This used to call error, but if we've run out of memory, we could
3397 get infinite recursion trying to build the string. */
3398 while (1)
3399 Fsignal (Qnil, Vmemory_signal_data);
3400 }
3401
3402 /* If we released our reserve (due to running out of memory),
3403 and we have a fair amount free once again,
3404 try to set aside another reserve in case we run out once more.
3405
3406 This is called when a relocatable block is freed in ralloc.c,
3407 and also directly from this file, in case we're not using ralloc.c. */
3408
3409 void
3410 refill_memory_reserve ()
3411 {
3412 #ifndef SYSTEM_MALLOC
3413 if (spare_memory[0] == 0)
3414 spare_memory[0] = (char *) malloc ((size_t) SPARE_MEMORY);
3415 if (spare_memory[1] == 0)
3416 spare_memory[1] = (char *) lisp_align_malloc (sizeof (struct cons_block),
3417 MEM_TYPE_CONS);
3418 if (spare_memory[2] == 0)
3419 spare_memory[2] = (char *) lisp_align_malloc (sizeof (struct cons_block),
3420 MEM_TYPE_CONS);
3421 if (spare_memory[3] == 0)
3422 spare_memory[3] = (char *) lisp_align_malloc (sizeof (struct cons_block),
3423 MEM_TYPE_CONS);
3424 if (spare_memory[4] == 0)
3425 spare_memory[4] = (char *) lisp_align_malloc (sizeof (struct cons_block),
3426 MEM_TYPE_CONS);
3427 if (spare_memory[5] == 0)
3428 spare_memory[5] = (char *) lisp_malloc (sizeof (struct string_block),
3429 MEM_TYPE_STRING);
3430 if (spare_memory[6] == 0)
3431 spare_memory[6] = (char *) lisp_malloc (sizeof (struct string_block),
3432 MEM_TYPE_STRING);
3433 if (spare_memory[0] && spare_memory[1] && spare_memory[5])
3434 Vmemory_full = Qnil;
3435 #endif
3436 }
3437 \f
3438 /************************************************************************
3439 C Stack Marking
3440 ************************************************************************/
3441
3442 #if GC_MARK_STACK || defined GC_MALLOC_CHECK
3443
3444 /* Conservative C stack marking requires a method to identify possibly
3445 live Lisp objects given a pointer value. We do this by keeping
3446 track of blocks of Lisp data that are allocated in a red-black tree
3447 (see also the comment of mem_node which is the type of nodes in
3448 that tree). Function lisp_malloc adds information for an allocated
3449 block to the red-black tree with calls to mem_insert, and function
3450 lisp_free removes it with mem_delete. Functions live_string_p etc
3451 call mem_find to lookup information about a given pointer in the
3452 tree, and use that to determine if the pointer points to a Lisp
3453 object or not. */
3454
3455 /* Initialize this part of alloc.c. */
3456
3457 static void
3458 mem_init ()
3459 {
3460 mem_z.left = mem_z.right = MEM_NIL;
3461 mem_z.parent = NULL;
3462 mem_z.color = MEM_BLACK;
3463 mem_z.start = mem_z.end = NULL;
3464 mem_root = MEM_NIL;
3465 }
3466
3467
3468 /* Value is a pointer to the mem_node containing START. Value is
3469 MEM_NIL if there is no node in the tree containing START. */
3470
3471 static INLINE struct mem_node *
3472 mem_find (start)
3473 void *start;
3474 {
3475 struct mem_node *p;
3476
3477 if (start < min_heap_address || start > max_heap_address)
3478 return MEM_NIL;
3479
3480 /* Make the search always successful to speed up the loop below. */
3481 mem_z.start = start;
3482 mem_z.end = (char *) start + 1;
3483
3484 p = mem_root;
3485 while (start < p->start || start >= p->end)
3486 p = start < p->start ? p->left : p->right;
3487 return p;
3488 }
3489
3490
3491 /* Insert a new node into the tree for a block of memory with start
3492 address START, end address END, and type TYPE. Value is a
3493 pointer to the node that was inserted. */
3494
3495 static struct mem_node *
3496 mem_insert (start, end, type)
3497 void *start, *end;
3498 enum mem_type type;
3499 {
3500 struct mem_node *c, *parent, *x;
3501
3502 if (start < min_heap_address)
3503 min_heap_address = start;
3504 if (end > max_heap_address)
3505 max_heap_address = end;
3506
3507 /* See where in the tree a node for START belongs. In this
3508 particular application, it shouldn't happen that a node is already
3509 present. For debugging purposes, let's check that. */
3510 c = mem_root;
3511 parent = NULL;
3512
3513 #if GC_MARK_STACK != GC_MAKE_GCPROS_NOOPS
3514
3515 while (c != MEM_NIL)
3516 {
3517 if (start >= c->start && start < c->end)
3518 abort ();
3519 parent = c;
3520 c = start < c->start ? c->left : c->right;
3521 }
3522
3523 #else /* GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS */
3524
3525 while (c != MEM_NIL)
3526 {
3527 parent = c;
3528 c = start < c->start ? c->left : c->right;
3529 }
3530
3531 #endif /* GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS */
3532
3533 /* Create a new node. */
3534 #ifdef GC_MALLOC_CHECK
3535 x = (struct mem_node *) _malloc_internal (sizeof *x);
3536 if (x == NULL)
3537 abort ();
3538 #else
3539 x = (struct mem_node *) xmalloc (sizeof *x);
3540 #endif
3541 x->start = start;
3542 x->end = end;
3543 x->type = type;
3544 x->parent = parent;
3545 x->left = x->right = MEM_NIL;
3546 x->color = MEM_RED;
3547
3548 /* Insert it as child of PARENT or install it as root. */
3549 if (parent)
3550 {
3551 if (start < parent->start)
3552 parent->left = x;
3553 else
3554 parent->right = x;
3555 }
3556 else
3557 mem_root = x;
3558
3559 /* Re-establish red-black tree properties. */
3560 mem_insert_fixup (x);
3561
3562 return x;
3563 }
3564
3565
3566 /* Re-establish the red-black properties of the tree, and thereby
3567 balance the tree, after node X has been inserted; X is always red. */
3568
3569 static void
3570 mem_insert_fixup (x)
3571 struct mem_node *x;
3572 {
3573 while (x != mem_root && x->parent->color == MEM_RED)
3574 {
3575 /* X is red and its parent is red. This is a violation of
3576 red-black tree property #3. */
3577
3578 if (x->parent == x->parent->parent->left)
3579 {
3580 /* We're on the left side of our grandparent, and Y is our
3581 "uncle". */
3582 struct mem_node *y = x->parent->parent->right;
3583
3584 if (y->color == MEM_RED)
3585 {
3586 /* Uncle and parent are red but should be black because
3587 X is red. Change the colors accordingly and proceed
3588 with the grandparent. */
3589 x->parent->color = MEM_BLACK;
3590 y->color = MEM_BLACK;
3591 x->parent->parent->color = MEM_RED;
3592 x = x->parent->parent;
3593 }
3594 else
3595 {
3596 /* Parent and uncle have different colors; parent is
3597 red, uncle is black. */
3598 if (x == x->parent->right)
3599 {
3600 x = x->parent;
3601 mem_rotate_left (x);
3602 }
3603
3604 x->parent->color = MEM_BLACK;
3605 x->parent->parent->color = MEM_RED;
3606 mem_rotate_right (x->parent->parent);
3607 }
3608 }
3609 else
3610 {
3611 /* This is the symmetrical case of above. */
3612 struct mem_node *y = x->parent->parent->left;
3613
3614 if (y->color == MEM_RED)
3615 {
3616 x->parent->color = MEM_BLACK;
3617 y->color = MEM_BLACK;
3618 x->parent->parent->color = MEM_RED;
3619 x = x->parent->parent;
3620 }
3621 else
3622 {
3623 if (x == x->parent->left)
3624 {
3625 x = x->parent;
3626 mem_rotate_right (x);
3627 }
3628
3629 x->parent->color = MEM_BLACK;
3630 x->parent->parent->color = MEM_RED;
3631 mem_rotate_left (x->parent->parent);
3632 }
3633 }
3634 }
3635
3636 /* The root may have been changed to red due to the algorithm. Set
3637 it to black so that property #5 is satisfied. */
3638 mem_root->color = MEM_BLACK;
3639 }
3640
3641
3642 /* (x) (y)
3643 / \ / \
3644 a (y) ===> (x) c
3645 / \ / \
3646 b c a b */
3647
3648 static void
3649 mem_rotate_left (x)
3650 struct mem_node *x;
3651 {
3652 struct mem_node *y;
3653
3654 /* Turn y's left sub-tree into x's right sub-tree. */
3655 y = x->right;
3656 x->right = y->left;
3657 if (y->left != MEM_NIL)
3658 y->left->parent = x;
3659
3660 /* Y's parent was x's parent. */
3661 if (y != MEM_NIL)
3662 y->parent = x->parent;
3663
3664 /* Get the parent to point to y instead of x. */
3665 if (x->parent)
3666 {
3667 if (x == x->parent->left)
3668 x->parent->left = y;
3669 else
3670 x->parent->right = y;
3671 }
3672 else
3673 mem_root = y;
3674
3675 /* Put x on y's left. */
3676 y->left = x;
3677 if (x != MEM_NIL)
3678 x->parent = y;
3679 }
3680
3681
3682 /* (x) (Y)
3683 / \ / \
3684 (y) c ===> a (x)
3685 / \ / \
3686 a b b c */
3687
3688 static void
3689 mem_rotate_right (x)
3690 struct mem_node *x;
3691 {
3692 struct mem_node *y = x->left;
3693
3694 x->left = y->right;
3695 if (y->right != MEM_NIL)
3696 y->right->parent = x;
3697
3698 if (y != MEM_NIL)
3699 y->parent = x->parent;
3700 if (x->parent)
3701 {
3702 if (x == x->parent->right)
3703 x->parent->right = y;
3704 else
3705 x->parent->left = y;
3706 }
3707 else
3708 mem_root = y;
3709
3710 y->right = x;
3711 if (x != MEM_NIL)
3712 x->parent = y;
3713 }
3714
3715
3716 /* Delete node Z from the tree. If Z is null or MEM_NIL, do nothing. */
3717
3718 static void
3719 mem_delete (z)
3720 struct mem_node *z;
3721 {
3722 struct mem_node *x, *y;
3723
3724 if (!z || z == MEM_NIL)
3725 return;
3726
3727 if (z->left == MEM_NIL || z->right == MEM_NIL)
3728 y = z;
3729 else
3730 {
3731 y = z->right;
3732 while (y->left != MEM_NIL)
3733 y = y->left;
3734 }
3735
3736 if (y->left != MEM_NIL)
3737 x = y->left;
3738 else
3739 x = y->right;
3740
3741 x->parent = y->parent;
3742 if (y->parent)
3743 {
3744 if (y == y->parent->left)
3745 y->parent->left = x;
3746 else
3747 y->parent->right = x;
3748 }
3749 else
3750 mem_root = x;
3751
3752 if (y != z)
3753 {
3754 z->start = y->start;
3755 z->end = y->end;
3756 z->type = y->type;
3757 }
3758
3759 if (y->color == MEM_BLACK)
3760 mem_delete_fixup (x);
3761
3762 #ifdef GC_MALLOC_CHECK
3763 _free_internal (y);
3764 #else
3765 xfree (y);
3766 #endif
3767 }
3768
3769
3770 /* Re-establish the red-black properties of the tree, after a
3771 deletion. */
3772
3773 static void
3774 mem_delete_fixup (x)
3775 struct mem_node *x;
3776 {
3777 while (x != mem_root && x->color == MEM_BLACK)
3778 {
3779 if (x == x->parent->left)
3780 {
3781 struct mem_node *w = x->parent->right;
3782
3783 if (w->color == MEM_RED)
3784 {
3785 w->color = MEM_BLACK;
3786 x->parent->color = MEM_RED;
3787 mem_rotate_left (x->parent);
3788 w = x->parent->right;
3789 }
3790
3791 if (w->left->color == MEM_BLACK && w->right->color == MEM_BLACK)
3792 {
3793 w->color = MEM_RED;
3794 x = x->parent;
3795 }
3796 else
3797 {
3798 if (w->right->color == MEM_BLACK)
3799 {
3800 w->left->color = MEM_BLACK;
3801 w->color = MEM_RED;
3802 mem_rotate_right (w);
3803 w = x->parent->right;
3804 }
3805 w->color = x->parent->color;
3806 x->parent->color = MEM_BLACK;
3807 w->right->color = MEM_BLACK;
3808 mem_rotate_left (x->parent);
3809 x = mem_root;
3810 }
3811 }
3812 else
3813 {
3814 struct mem_node *w = x->parent->left;
3815
3816 if (w->color == MEM_RED)
3817 {
3818 w->color = MEM_BLACK;
3819 x->parent->color = MEM_RED;
3820 mem_rotate_right (x->parent);
3821 w = x->parent->left;
3822 }
3823
3824 if (w->right->color == MEM_BLACK && w->left->color == MEM_BLACK)
3825 {
3826 w->color = MEM_RED;
3827 x = x->parent;
3828 }
3829 else
3830 {
3831 if (w->left->color == MEM_BLACK)
3832 {
3833 w->right->color = MEM_BLACK;
3834 w->color = MEM_RED;
3835 mem_rotate_left (w);
3836 w = x->parent->left;
3837 }
3838
3839 w->color = x->parent->color;
3840 x->parent->color = MEM_BLACK;
3841 w->left->color = MEM_BLACK;
3842 mem_rotate_right (x->parent);
3843 x = mem_root;
3844 }
3845 }
3846 }
3847
3848 x->color = MEM_BLACK;
3849 }
3850
3851
3852 /* Value is non-zero if P is a pointer to a live Lisp string on
3853 the heap. M is a pointer to the mem_block for P. */
3854
3855 static INLINE int
3856 live_string_p (m, p)
3857 struct mem_node *m;
3858 void *p;
3859 {
3860 if (m->type == MEM_TYPE_STRING)
3861 {
3862 struct string_block *b = (struct string_block *) m->start;
3863 int offset = (char *) p - (char *) &b->strings[0];
3864
3865 /* P must point to the start of a Lisp_String structure, and it
3866 must not be on the free-list. */
3867 return (offset >= 0
3868 && offset % sizeof b->strings[0] == 0
3869 && offset < (STRING_BLOCK_SIZE * sizeof b->strings[0])
3870 && ((struct Lisp_String *) p)->data != NULL);
3871 }
3872 else
3873 return 0;
3874 }
3875
3876
3877 /* Value is non-zero if P is a pointer to a live Lisp cons on
3878 the heap. M is a pointer to the mem_block for P. */
3879
3880 static INLINE int
3881 live_cons_p (m, p)
3882 struct mem_node *m;
3883 void *p;
3884 {
3885 if (m->type == MEM_TYPE_CONS)
3886 {
3887 struct cons_block *b = (struct cons_block *) m->start;
3888 int offset = (char *) p - (char *) &b->conses[0];
3889
3890 /* P must point to the start of a Lisp_Cons, not be
3891 one of the unused cells in the current cons block,
3892 and not be on the free-list. */
3893 return (offset >= 0
3894 && offset % sizeof b->conses[0] == 0
3895 && offset < (CONS_BLOCK_SIZE * sizeof b->conses[0])
3896 && (b != cons_block
3897 || offset / sizeof b->conses[0] < cons_block_index)
3898 && !EQ (((struct Lisp_Cons *) p)->car, Vdead));
3899 }
3900 else
3901 return 0;
3902 }
3903
3904
3905 /* Value is non-zero if P is a pointer to a live Lisp symbol on
3906 the heap. M is a pointer to the mem_block for P. */
3907
3908 static INLINE int
3909 live_symbol_p (m, p)
3910 struct mem_node *m;
3911 void *p;
3912 {
3913 if (m->type == MEM_TYPE_SYMBOL)
3914 {
3915 struct symbol_block *b = (struct symbol_block *) m->start;
3916 int offset = (char *) p - (char *) &b->symbols[0];
3917
3918 /* P must point to the start of a Lisp_Symbol, not be
3919 one of the unused cells in the current symbol block,
3920 and not be on the free-list. */
3921 return (offset >= 0
3922 && offset % sizeof b->symbols[0] == 0
3923 && offset < (SYMBOL_BLOCK_SIZE * sizeof b->symbols[0])
3924 && (b != symbol_block
3925 || offset / sizeof b->symbols[0] < symbol_block_index)
3926 && !EQ (((struct Lisp_Symbol *) p)->function, Vdead));
3927 }
3928 else
3929 return 0;
3930 }
3931
3932
3933 /* Value is non-zero if P is a pointer to a live Lisp float on
3934 the heap. M is a pointer to the mem_block for P. */
3935
3936 static INLINE int
3937 live_float_p (m, p)
3938 struct mem_node *m;
3939 void *p;
3940 {
3941 if (m->type == MEM_TYPE_FLOAT)
3942 {
3943 struct float_block *b = (struct float_block *) m->start;
3944 int offset = (char *) p - (char *) &b->floats[0];
3945
3946 /* P must point to the start of a Lisp_Float and not be
3947 one of the unused cells in the current float block. */
3948 return (offset >= 0
3949 && offset % sizeof b->floats[0] == 0
3950 && offset < (FLOAT_BLOCK_SIZE * sizeof b->floats[0])
3951 && (b != float_block
3952 || offset / sizeof b->floats[0] < float_block_index));
3953 }
3954 else
3955 return 0;
3956 }
3957
3958
3959 /* Value is non-zero if P is a pointer to a live Lisp Misc on
3960 the heap. M is a pointer to the mem_block for P. */
3961
3962 static INLINE int
3963 live_misc_p (m, p)
3964 struct mem_node *m;
3965 void *p;
3966 {
3967 if (m->type == MEM_TYPE_MISC)
3968 {
3969 struct marker_block *b = (struct marker_block *) m->start;
3970 int offset = (char *) p - (char *) &b->markers[0];
3971
3972 /* P must point to the start of a Lisp_Misc, not be
3973 one of the unused cells in the current misc block,
3974 and not be on the free-list. */
3975 return (offset >= 0
3976 && offset % sizeof b->markers[0] == 0
3977 && offset < (MARKER_BLOCK_SIZE * sizeof b->markers[0])
3978 && (b != marker_block
3979 || offset / sizeof b->markers[0] < marker_block_index)
3980 && ((union Lisp_Misc *) p)->u_marker.type != Lisp_Misc_Free);
3981 }
3982 else
3983 return 0;
3984 }
3985
3986
3987 /* Value is non-zero if P is a pointer to a live vector-like object.
3988 M is a pointer to the mem_block for P. */
3989
3990 static INLINE int
3991 live_vector_p (m, p)
3992 struct mem_node *m;
3993 void *p;
3994 {
3995 return (p == m->start
3996 && m->type >= MEM_TYPE_VECTOR
3997 && m->type <= MEM_TYPE_WINDOW);
3998 }
3999
4000
4001 /* Value is non-zero if P is a pointer to a live buffer. M is a
4002 pointer to the mem_block for P. */
4003
4004 static INLINE int
4005 live_buffer_p (m, p)
4006 struct mem_node *m;
4007 void *p;
4008 {
4009 /* P must point to the start of the block, and the buffer
4010 must not have been killed. */
4011 return (m->type == MEM_TYPE_BUFFER
4012 && p == m->start
4013 && !NILP (((struct buffer *) p)->name));
4014 }
4015
4016 #endif /* GC_MARK_STACK || defined GC_MALLOC_CHECK */
4017
4018 #if GC_MARK_STACK
4019
4020 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
4021
4022 /* Array of objects that are kept alive because the C stack contains
4023 a pattern that looks like a reference to them . */
4024
4025 #define MAX_ZOMBIES 10
4026 static Lisp_Object zombies[MAX_ZOMBIES];
4027
4028 /* Number of zombie objects. */
4029
4030 static int nzombies;
4031
4032 /* Number of garbage collections. */
4033
4034 static int ngcs;
4035
4036 /* Average percentage of zombies per collection. */
4037
4038 static double avg_zombies;
4039
4040 /* Max. number of live and zombie objects. */
4041
4042 static int max_live, max_zombies;
4043
4044 /* Average number of live objects per GC. */
4045
4046 static double avg_live;
4047
4048 DEFUN ("gc-status", Fgc_status, Sgc_status, 0, 0, "",
4049 doc: /* Show information about live and zombie objects. */)
4050 ()
4051 {
4052 Lisp_Object args[8], zombie_list = Qnil;
4053 int i;
4054 for (i = 0; i < nzombies; i++)
4055 zombie_list = Fcons (zombies[i], zombie_list);
4056 args[0] = build_string ("%d GCs, avg live/zombies = %.2f/%.2f (%f%%), max %d/%d\nzombies: %S");
4057 args[1] = make_number (ngcs);
4058 args[2] = make_float (avg_live);
4059 args[3] = make_float (avg_zombies);
4060 args[4] = make_float (avg_zombies / avg_live / 100);
4061 args[5] = make_number (max_live);
4062 args[6] = make_number (max_zombies);
4063 args[7] = zombie_list;
4064 return Fmessage (8, args);
4065 }
4066
4067 #endif /* GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES */
4068
4069
4070 /* Mark OBJ if we can prove it's a Lisp_Object. */
4071
4072 static INLINE void
4073 mark_maybe_object (obj)
4074 Lisp_Object obj;
4075 {
4076 void *po = (void *) XPNTR (obj);
4077 struct mem_node *m = mem_find (po);
4078
4079 if (m != MEM_NIL)
4080 {
4081 int mark_p = 0;
4082
4083 switch (XGCTYPE (obj))
4084 {
4085 case Lisp_String:
4086 mark_p = (live_string_p (m, po)
4087 && !STRING_MARKED_P ((struct Lisp_String *) po));
4088 break;
4089
4090 case Lisp_Cons:
4091 mark_p = (live_cons_p (m, po) && !CONS_MARKED_P (XCONS (obj)));
4092 break;
4093
4094 case Lisp_Symbol:
4095 mark_p = (live_symbol_p (m, po) && !XSYMBOL (obj)->gcmarkbit);
4096 break;
4097
4098 case Lisp_Float:
4099 mark_p = (live_float_p (m, po) && !FLOAT_MARKED_P (XFLOAT (obj)));
4100 break;
4101
4102 case Lisp_Vectorlike:
4103 /* Note: can't check GC_BUFFERP before we know it's a
4104 buffer because checking that dereferences the pointer
4105 PO which might point anywhere. */
4106 if (live_vector_p (m, po))
4107 mark_p = !GC_SUBRP (obj) && !VECTOR_MARKED_P (XVECTOR (obj));
4108 else if (live_buffer_p (m, po))
4109 mark_p = GC_BUFFERP (obj) && !VECTOR_MARKED_P (XBUFFER (obj));
4110 break;
4111
4112 case Lisp_Misc:
4113 mark_p = (live_misc_p (m, po) && !XMARKER (obj)->gcmarkbit);
4114 break;
4115
4116 case Lisp_Int:
4117 case Lisp_Type_Limit:
4118 break;
4119 }
4120
4121 if (mark_p)
4122 {
4123 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
4124 if (nzombies < MAX_ZOMBIES)
4125 zombies[nzombies] = obj;
4126 ++nzombies;
4127 #endif
4128 mark_object (obj);
4129 }
4130 }
4131 }
4132
4133
4134 /* If P points to Lisp data, mark that as live if it isn't already
4135 marked. */
4136
4137 static INLINE void
4138 mark_maybe_pointer (p)
4139 void *p;
4140 {
4141 struct mem_node *m;
4142
4143 /* Quickly rule out some values which can't point to Lisp data. We
4144 assume that Lisp data is aligned on even addresses. */
4145 if ((EMACS_INT) p & 1)
4146 return;
4147
4148 m = mem_find (p);
4149 if (m != MEM_NIL)
4150 {
4151 Lisp_Object obj = Qnil;
4152
4153 switch (m->type)
4154 {
4155 case MEM_TYPE_NON_LISP:
4156 /* Nothing to do; not a pointer to Lisp memory. */
4157 break;
4158
4159 case MEM_TYPE_BUFFER:
4160 if (live_buffer_p (m, p) && !VECTOR_MARKED_P((struct buffer *)p))
4161 XSETVECTOR (obj, p);
4162 break;
4163
4164 case MEM_TYPE_CONS:
4165 if (live_cons_p (m, p) && !CONS_MARKED_P ((struct Lisp_Cons *) p))
4166 XSETCONS (obj, p);
4167 break;
4168
4169 case MEM_TYPE_STRING:
4170 if (live_string_p (m, p)
4171 && !STRING_MARKED_P ((struct Lisp_String *) p))
4172 XSETSTRING (obj, p);
4173 break;
4174
4175 case MEM_TYPE_MISC:
4176 if (live_misc_p (m, p) && !((struct Lisp_Free *) p)->gcmarkbit)
4177 XSETMISC (obj, p);
4178 break;
4179
4180 case MEM_TYPE_SYMBOL:
4181 if (live_symbol_p (m, p) && !((struct Lisp_Symbol *) p)->gcmarkbit)
4182 XSETSYMBOL (obj, p);
4183 break;
4184
4185 case MEM_TYPE_FLOAT:
4186 if (live_float_p (m, p) && !FLOAT_MARKED_P (p))
4187 XSETFLOAT (obj, p);
4188 break;
4189
4190 case MEM_TYPE_VECTOR:
4191 case MEM_TYPE_PROCESS:
4192 case MEM_TYPE_HASH_TABLE:
4193 case MEM_TYPE_FRAME:
4194 case MEM_TYPE_WINDOW:
4195 if (live_vector_p (m, p))
4196 {
4197 Lisp_Object tem;
4198 XSETVECTOR (tem, p);
4199 if (!GC_SUBRP (tem) && !VECTOR_MARKED_P (XVECTOR (tem)))
4200 obj = tem;
4201 }
4202 break;
4203
4204 default:
4205 abort ();
4206 }
4207
4208 if (!GC_NILP (obj))
4209 mark_object (obj);
4210 }
4211 }
4212
4213
4214 /* Mark Lisp objects referenced from the address range START..END. */
4215
4216 static void
4217 mark_memory (start, end)
4218 void *start, *end;
4219 {
4220 Lisp_Object *p;
4221 void **pp;
4222
4223 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
4224 nzombies = 0;
4225 #endif
4226
4227 /* Make START the pointer to the start of the memory region,
4228 if it isn't already. */
4229 if (end < start)
4230 {
4231 void *tem = start;
4232 start = end;
4233 end = tem;
4234 }
4235
4236 /* Mark Lisp_Objects. */
4237 for (p = (Lisp_Object *) start; (void *) p < end; ++p)
4238 mark_maybe_object (*p);
4239
4240 /* Mark Lisp data pointed to. This is necessary because, in some
4241 situations, the C compiler optimizes Lisp objects away, so that
4242 only a pointer to them remains. Example:
4243
4244 DEFUN ("testme", Ftestme, Stestme, 0, 0, 0, "")
4245 ()
4246 {
4247 Lisp_Object obj = build_string ("test");
4248 struct Lisp_String *s = XSTRING (obj);
4249 Fgarbage_collect ();
4250 fprintf (stderr, "test `%s'\n", s->data);
4251 return Qnil;
4252 }
4253
4254 Here, `obj' isn't really used, and the compiler optimizes it
4255 away. The only reference to the life string is through the
4256 pointer `s'. */
4257
4258 for (pp = (void **) start; (void *) pp < end; ++pp)
4259 mark_maybe_pointer (*pp);
4260 }
4261
4262 /* setjmp will work with GCC unless NON_SAVING_SETJMP is defined in
4263 the GCC system configuration. In gcc 3.2, the only systems for
4264 which this is so are i386-sco5 non-ELF, i386-sysv3 (maybe included
4265 by others?) and ns32k-pc532-min. */
4266
4267 #if !defined GC_SAVE_REGISTERS_ON_STACK && !defined GC_SETJMP_WORKS
4268
4269 static int setjmp_tested_p, longjmps_done;
4270
4271 #define SETJMP_WILL_LIKELY_WORK "\
4272 \n\
4273 Emacs garbage collector has been changed to use conservative stack\n\
4274 marking. Emacs has determined that the method it uses to do the\n\
4275 marking will likely work on your system, but this isn't sure.\n\
4276 \n\
4277 If you are a system-programmer, or can get the help of a local wizard\n\
4278 who is, please take a look at the function mark_stack in alloc.c, and\n\
4279 verify that the methods used are appropriate for your system.\n\
4280 \n\
4281 Please mail the result to <emacs-devel@gnu.org>.\n\
4282 "
4283
4284 #define SETJMP_WILL_NOT_WORK "\
4285 \n\
4286 Emacs garbage collector has been changed to use conservative stack\n\
4287 marking. Emacs has determined that the default method it uses to do the\n\
4288 marking will not work on your system. We will need a system-dependent\n\
4289 solution for your system.\n\
4290 \n\
4291 Please take a look at the function mark_stack in alloc.c, and\n\
4292 try to find a way to make it work on your system.\n\
4293 \n\
4294 Note that you may get false negatives, depending on the compiler.\n\
4295 In particular, you need to use -O with GCC for this test.\n\
4296 \n\
4297 Please mail the result to <emacs-devel@gnu.org>.\n\
4298 "
4299
4300
4301 /* Perform a quick check if it looks like setjmp saves registers in a
4302 jmp_buf. Print a message to stderr saying so. When this test
4303 succeeds, this is _not_ a proof that setjmp is sufficient for
4304 conservative stack marking. Only the sources or a disassembly
4305 can prove that. */
4306
4307 static void
4308 test_setjmp ()
4309 {
4310 char buf[10];
4311 register int x;
4312 jmp_buf jbuf;
4313 int result = 0;
4314
4315 /* Arrange for X to be put in a register. */
4316 sprintf (buf, "1");
4317 x = strlen (buf);
4318 x = 2 * x - 1;
4319
4320 setjmp (jbuf);
4321 if (longjmps_done == 1)
4322 {
4323 /* Came here after the longjmp at the end of the function.
4324
4325 If x == 1, the longjmp has restored the register to its
4326 value before the setjmp, and we can hope that setjmp
4327 saves all such registers in the jmp_buf, although that
4328 isn't sure.
4329
4330 For other values of X, either something really strange is
4331 taking place, or the setjmp just didn't save the register. */
4332
4333 if (x == 1)
4334 fprintf (stderr, SETJMP_WILL_LIKELY_WORK);
4335 else
4336 {
4337 fprintf (stderr, SETJMP_WILL_NOT_WORK);
4338 exit (1);
4339 }
4340 }
4341
4342 ++longjmps_done;
4343 x = 2;
4344 if (longjmps_done == 1)
4345 longjmp (jbuf, 1);
4346 }
4347
4348 #endif /* not GC_SAVE_REGISTERS_ON_STACK && not GC_SETJMP_WORKS */
4349
4350
4351 #if GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS
4352
4353 /* Abort if anything GCPRO'd doesn't survive the GC. */
4354
4355 static void
4356 check_gcpros ()
4357 {
4358 struct gcpro *p;
4359 int i;
4360
4361 for (p = gcprolist; p; p = p->next)
4362 for (i = 0; i < p->nvars; ++i)
4363 if (!survives_gc_p (p->var[i]))
4364 /* FIXME: It's not necessarily a bug. It might just be that the
4365 GCPRO is unnecessary or should release the object sooner. */
4366 abort ();
4367 }
4368
4369 #elif GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
4370
4371 static void
4372 dump_zombies ()
4373 {
4374 int i;
4375
4376 fprintf (stderr, "\nZombies kept alive = %d:\n", nzombies);
4377 for (i = 0; i < min (MAX_ZOMBIES, nzombies); ++i)
4378 {
4379 fprintf (stderr, " %d = ", i);
4380 debug_print (zombies[i]);
4381 }
4382 }
4383
4384 #endif /* GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES */
4385
4386
4387 /* Mark live Lisp objects on the C stack.
4388
4389 There are several system-dependent problems to consider when
4390 porting this to new architectures:
4391
4392 Processor Registers
4393
4394 We have to mark Lisp objects in CPU registers that can hold local
4395 variables or are used to pass parameters.
4396
4397 If GC_SAVE_REGISTERS_ON_STACK is defined, it should expand to
4398 something that either saves relevant registers on the stack, or
4399 calls mark_maybe_object passing it each register's contents.
4400
4401 If GC_SAVE_REGISTERS_ON_STACK is not defined, the current
4402 implementation assumes that calling setjmp saves registers we need
4403 to see in a jmp_buf which itself lies on the stack. This doesn't
4404 have to be true! It must be verified for each system, possibly
4405 by taking a look at the source code of setjmp.
4406
4407 Stack Layout
4408
4409 Architectures differ in the way their processor stack is organized.
4410 For example, the stack might look like this
4411
4412 +----------------+
4413 | Lisp_Object | size = 4
4414 +----------------+
4415 | something else | size = 2
4416 +----------------+
4417 | Lisp_Object | size = 4
4418 +----------------+
4419 | ... |
4420
4421 In such a case, not every Lisp_Object will be aligned equally. To
4422 find all Lisp_Object on the stack it won't be sufficient to walk
4423 the stack in steps of 4 bytes. Instead, two passes will be
4424 necessary, one starting at the start of the stack, and a second
4425 pass starting at the start of the stack + 2. Likewise, if the
4426 minimal alignment of Lisp_Objects on the stack is 1, four passes
4427 would be necessary, each one starting with one byte more offset
4428 from the stack start.
4429
4430 The current code assumes by default that Lisp_Objects are aligned
4431 equally on the stack. */
4432
4433 static void
4434 mark_stack ()
4435 {
4436 int i;
4437 jmp_buf j;
4438 volatile int stack_grows_down_p = (char *) &j > (char *) stack_base;
4439 void *end;
4440
4441 /* This trick flushes the register windows so that all the state of
4442 the process is contained in the stack. */
4443 /* Fixme: Code in the Boehm GC suggests flushing (with `flushrs') is
4444 needed on ia64 too. See mach_dep.c, where it also says inline
4445 assembler doesn't work with relevant proprietary compilers. */
4446 #ifdef sparc
4447 asm ("ta 3");
4448 #endif
4449
4450 /* Save registers that we need to see on the stack. We need to see
4451 registers used to hold register variables and registers used to
4452 pass parameters. */
4453 #ifdef GC_SAVE_REGISTERS_ON_STACK
4454 GC_SAVE_REGISTERS_ON_STACK (end);
4455 #else /* not GC_SAVE_REGISTERS_ON_STACK */
4456
4457 #ifndef GC_SETJMP_WORKS /* If it hasn't been checked yet that
4458 setjmp will definitely work, test it
4459 and print a message with the result
4460 of the test. */
4461 if (!setjmp_tested_p)
4462 {
4463 setjmp_tested_p = 1;
4464 test_setjmp ();
4465 }
4466 #endif /* GC_SETJMP_WORKS */
4467
4468 setjmp (j);
4469 end = stack_grows_down_p ? (char *) &j + sizeof j : (char *) &j;
4470 #endif /* not GC_SAVE_REGISTERS_ON_STACK */
4471
4472 /* This assumes that the stack is a contiguous region in memory. If
4473 that's not the case, something has to be done here to iterate
4474 over the stack segments. */
4475 #ifndef GC_LISP_OBJECT_ALIGNMENT
4476 #ifdef __GNUC__
4477 #define GC_LISP_OBJECT_ALIGNMENT __alignof__ (Lisp_Object)
4478 #else
4479 #define GC_LISP_OBJECT_ALIGNMENT sizeof (Lisp_Object)
4480 #endif
4481 #endif
4482 for (i = 0; i < sizeof (Lisp_Object); i += GC_LISP_OBJECT_ALIGNMENT)
4483 mark_memory ((char *) stack_base + i, end);
4484 /* Allow for marking a secondary stack, like the register stack on the
4485 ia64. */
4486 #ifdef GC_MARK_SECONDARY_STACK
4487 GC_MARK_SECONDARY_STACK ();
4488 #endif
4489
4490 #if GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS
4491 check_gcpros ();
4492 #endif
4493 }
4494
4495 #endif /* GC_MARK_STACK != 0 */
4496
4497
4498
4499 /* Return 1 if OBJ is a valid lisp object.
4500 Return 0 if OBJ is NOT a valid lisp object.
4501 Return -1 if we cannot validate OBJ.
4502 This function can be quite slow,
4503 so it should only be used in code for manual debugging. */
4504
4505 int
4506 valid_lisp_object_p (obj)
4507 Lisp_Object obj;
4508 {
4509 void *p;
4510 #if !GC_MARK_STACK
4511 int fd;
4512 #else
4513 struct mem_node *m;
4514 #endif
4515
4516 if (INTEGERP (obj))
4517 return 1;
4518
4519 p = (void *) XPNTR (obj);
4520 if (PURE_POINTER_P (p))
4521 return 1;
4522
4523 #if !GC_MARK_STACK
4524 /* We need to determine whether it is safe to access memory at
4525 address P. Obviously, we cannot just access it (we would SEGV
4526 trying), so we trick the o/s to tell us whether p is a valid
4527 pointer. Unfortunately, we cannot use NULL_DEVICE here, as
4528 emacs_write may not validate p in that case. */
4529 if ((fd = emacs_open ("__Valid__Lisp__Object__", O_CREAT | O_WRONLY | O_TRUNC, 0666)) >= 0)
4530 {
4531 int valid = (emacs_write (fd, (char *)p, 16) == 16);
4532 emacs_close (fd);
4533 unlink ("__Valid__Lisp__Object__");
4534 return valid;
4535 }
4536
4537 return -1;
4538 #else
4539
4540 m = mem_find (p);
4541
4542 if (m == MEM_NIL)
4543 return 0;
4544
4545 switch (m->type)
4546 {
4547 case MEM_TYPE_NON_LISP:
4548 return 0;
4549
4550 case MEM_TYPE_BUFFER:
4551 return live_buffer_p (m, p);
4552
4553 case MEM_TYPE_CONS:
4554 return live_cons_p (m, p);
4555
4556 case MEM_TYPE_STRING:
4557 return live_string_p (m, p);
4558
4559 case MEM_TYPE_MISC:
4560 return live_misc_p (m, p);
4561
4562 case MEM_TYPE_SYMBOL:
4563 return live_symbol_p (m, p);
4564
4565 case MEM_TYPE_FLOAT:
4566 return live_float_p (m, p);
4567
4568 case MEM_TYPE_VECTOR:
4569 case MEM_TYPE_PROCESS:
4570 case MEM_TYPE_HASH_TABLE:
4571 case MEM_TYPE_FRAME:
4572 case MEM_TYPE_WINDOW:
4573 return live_vector_p (m, p);
4574
4575 default:
4576 break;
4577 }
4578
4579 return 0;
4580 #endif
4581 }
4582
4583
4584
4585 \f
4586 /***********************************************************************
4587 Pure Storage Management
4588 ***********************************************************************/
4589
4590 /* Allocate room for SIZE bytes from pure Lisp storage and return a
4591 pointer to it. TYPE is the Lisp type for which the memory is
4592 allocated. TYPE < 0 means it's not used for a Lisp object.
4593
4594 If store_pure_type_info is set and TYPE is >= 0, the type of
4595 the allocated object is recorded in pure_types. */
4596
4597 static POINTER_TYPE *
4598 pure_alloc (size, type)
4599 size_t size;
4600 int type;
4601 {
4602 POINTER_TYPE *result;
4603 #ifdef USE_LSB_TAG
4604 size_t alignment = (1 << GCTYPEBITS);
4605 #else
4606 size_t alignment = sizeof (EMACS_INT);
4607
4608 /* Give Lisp_Floats an extra alignment. */
4609 if (type == Lisp_Float)
4610 {
4611 #if defined __GNUC__ && __GNUC__ >= 2
4612 alignment = __alignof (struct Lisp_Float);
4613 #else
4614 alignment = sizeof (struct Lisp_Float);
4615 #endif
4616 }
4617 #endif
4618
4619 again:
4620 result = ALIGN (purebeg + pure_bytes_used, alignment);
4621 pure_bytes_used = ((char *)result - (char *)purebeg) + size;
4622
4623 if (pure_bytes_used <= pure_size)
4624 return result;
4625
4626 /* Don't allocate a large amount here,
4627 because it might get mmap'd and then its address
4628 might not be usable. */
4629 purebeg = (char *) xmalloc (10000);
4630 pure_size = 10000;
4631 pure_bytes_used_before_overflow += pure_bytes_used - size;
4632 pure_bytes_used = 0;
4633 goto again;
4634 }
4635
4636
4637 /* Print a warning if PURESIZE is too small. */
4638
4639 void
4640 check_pure_size ()
4641 {
4642 if (pure_bytes_used_before_overflow)
4643 message ("Pure Lisp storage overflow (approx. %d bytes needed)",
4644 (int) (pure_bytes_used + pure_bytes_used_before_overflow));
4645 }
4646
4647
4648 /* Return a string allocated in pure space. DATA is a buffer holding
4649 NCHARS characters, and NBYTES bytes of string data. MULTIBYTE
4650 non-zero means make the result string multibyte.
4651
4652 Must get an error if pure storage is full, since if it cannot hold
4653 a large string it may be able to hold conses that point to that
4654 string; then the string is not protected from gc. */
4655
4656 Lisp_Object
4657 make_pure_string (data, nchars, nbytes, multibyte)
4658 char *data;
4659 int nchars, nbytes;
4660 int multibyte;
4661 {
4662 Lisp_Object string;
4663 struct Lisp_String *s;
4664
4665 s = (struct Lisp_String *) pure_alloc (sizeof *s, Lisp_String);
4666 s->data = (unsigned char *) pure_alloc (nbytes + 1, -1);
4667 s->size = nchars;
4668 s->size_byte = multibyte ? nbytes : -1;
4669 bcopy (data, s->data, nbytes);
4670 s->data[nbytes] = '\0';
4671 s->intervals = NULL_INTERVAL;
4672 XSETSTRING (string, s);
4673 return string;
4674 }
4675
4676
4677 /* Return a cons allocated from pure space. Give it pure copies
4678 of CAR as car and CDR as cdr. */
4679
4680 Lisp_Object
4681 pure_cons (car, cdr)
4682 Lisp_Object car, cdr;
4683 {
4684 register Lisp_Object new;
4685 struct Lisp_Cons *p;
4686
4687 p = (struct Lisp_Cons *) pure_alloc (sizeof *p, Lisp_Cons);
4688 XSETCONS (new, p);
4689 XSETCAR (new, Fpurecopy (car));
4690 XSETCDR (new, Fpurecopy (cdr));
4691 return new;
4692 }
4693
4694
4695 /* Value is a float object with value NUM allocated from pure space. */
4696
4697 Lisp_Object
4698 make_pure_float (num)
4699 double num;
4700 {
4701 register Lisp_Object new;
4702 struct Lisp_Float *p;
4703
4704 p = (struct Lisp_Float *) pure_alloc (sizeof *p, Lisp_Float);
4705 XSETFLOAT (new, p);
4706 XFLOAT_DATA (new) = num;
4707 return new;
4708 }
4709
4710
4711 /* Return a vector with room for LEN Lisp_Objects allocated from
4712 pure space. */
4713
4714 Lisp_Object
4715 make_pure_vector (len)
4716 EMACS_INT len;
4717 {
4718 Lisp_Object new;
4719 struct Lisp_Vector *p;
4720 size_t size = sizeof *p + (len - 1) * sizeof (Lisp_Object);
4721
4722 p = (struct Lisp_Vector *) pure_alloc (size, Lisp_Vectorlike);
4723 XSETVECTOR (new, p);
4724 XVECTOR (new)->size = len;
4725 return new;
4726 }
4727
4728
4729 DEFUN ("purecopy", Fpurecopy, Spurecopy, 1, 1, 0,
4730 doc: /* Make a copy of OBJECT in pure storage.
4731 Recursively copies contents of vectors and cons cells.
4732 Does not copy symbols. Copies strings without text properties. */)
4733 (obj)
4734 register Lisp_Object obj;
4735 {
4736 if (NILP (Vpurify_flag))
4737 return obj;
4738
4739 if (PURE_POINTER_P (XPNTR (obj)))
4740 return obj;
4741
4742 if (CONSP (obj))
4743 return pure_cons (XCAR (obj), XCDR (obj));
4744 else if (FLOATP (obj))
4745 return make_pure_float (XFLOAT_DATA (obj));
4746 else if (STRINGP (obj))
4747 return make_pure_string (SDATA (obj), SCHARS (obj),
4748 SBYTES (obj),
4749 STRING_MULTIBYTE (obj));
4750 else if (COMPILEDP (obj) || VECTORP (obj))
4751 {
4752 register struct Lisp_Vector *vec;
4753 register int i;
4754 EMACS_INT size;
4755
4756 size = XVECTOR (obj)->size;
4757 if (size & PSEUDOVECTOR_FLAG)
4758 size &= PSEUDOVECTOR_SIZE_MASK;
4759 vec = XVECTOR (make_pure_vector (size));
4760 for (i = 0; i < size; i++)
4761 vec->contents[i] = Fpurecopy (XVECTOR (obj)->contents[i]);
4762 if (COMPILEDP (obj))
4763 XSETCOMPILED (obj, vec);
4764 else
4765 XSETVECTOR (obj, vec);
4766 return obj;
4767 }
4768 else if (MARKERP (obj))
4769 error ("Attempt to copy a marker to pure storage");
4770
4771 return obj;
4772 }
4773
4774
4775 \f
4776 /***********************************************************************
4777 Protection from GC
4778 ***********************************************************************/
4779
4780 /* Put an entry in staticvec, pointing at the variable with address
4781 VARADDRESS. */
4782
4783 void
4784 staticpro (varaddress)
4785 Lisp_Object *varaddress;
4786 {
4787 staticvec[staticidx++] = varaddress;
4788 if (staticidx >= NSTATICS)
4789 abort ();
4790 }
4791
4792 struct catchtag
4793 {
4794 Lisp_Object tag;
4795 Lisp_Object val;
4796 struct catchtag *next;
4797 };
4798
4799 \f
4800 /***********************************************************************
4801 Protection from GC
4802 ***********************************************************************/
4803
4804 /* Temporarily prevent garbage collection. */
4805
4806 int
4807 inhibit_garbage_collection ()
4808 {
4809 int count = SPECPDL_INDEX ();
4810 int nbits = min (VALBITS, BITS_PER_INT);
4811
4812 specbind (Qgc_cons_threshold, make_number (((EMACS_INT) 1 << (nbits - 1)) - 1));
4813 return count;
4814 }
4815
4816
4817 DEFUN ("garbage-collect", Fgarbage_collect, Sgarbage_collect, 0, 0, "",
4818 doc: /* Reclaim storage for Lisp objects no longer needed.
4819 Garbage collection happens automatically if you cons more than
4820 `gc-cons-threshold' bytes of Lisp data since previous garbage collection.
4821 `garbage-collect' normally returns a list with info on amount of space in use:
4822 ((USED-CONSES . FREE-CONSES) (USED-SYMS . FREE-SYMS)
4823 (USED-MARKERS . FREE-MARKERS) USED-STRING-CHARS USED-VECTOR-SLOTS
4824 (USED-FLOATS . FREE-FLOATS) (USED-INTERVALS . FREE-INTERVALS)
4825 (USED-STRINGS . FREE-STRINGS))
4826 However, if there was overflow in pure space, `garbage-collect'
4827 returns nil, because real GC can't be done. */)
4828 ()
4829 {
4830 register struct specbinding *bind;
4831 struct catchtag *catch;
4832 struct handler *handler;
4833 char stack_top_variable;
4834 register int i;
4835 int message_p;
4836 Lisp_Object total[8];
4837 int count = SPECPDL_INDEX ();
4838 EMACS_TIME t1, t2, t3;
4839
4840 if (abort_on_gc)
4841 abort ();
4842
4843 /* Can't GC if pure storage overflowed because we can't determine
4844 if something is a pure object or not. */
4845 if (pure_bytes_used_before_overflow)
4846 return Qnil;
4847
4848 CHECK_CONS_LIST ();
4849
4850 /* Don't keep undo information around forever.
4851 Do this early on, so it is no problem if the user quits. */
4852 {
4853 register struct buffer *nextb = all_buffers;
4854
4855 while (nextb)
4856 {
4857 /* If a buffer's undo list is Qt, that means that undo is
4858 turned off in that buffer. Calling truncate_undo_list on
4859 Qt tends to return NULL, which effectively turns undo back on.
4860 So don't call truncate_undo_list if undo_list is Qt. */
4861 if (! NILP (nextb->name) && ! EQ (nextb->undo_list, Qt))
4862 truncate_undo_list (nextb);
4863
4864 /* Shrink buffer gaps, but skip indirect and dead buffers. */
4865 if (nextb->base_buffer == 0 && !NILP (nextb->name))
4866 {
4867 /* If a buffer's gap size is more than 10% of the buffer
4868 size, or larger than 2000 bytes, then shrink it
4869 accordingly. Keep a minimum size of 20 bytes. */
4870 int size = min (2000, max (20, (nextb->text->z_byte / 10)));
4871
4872 if (nextb->text->gap_size > size)
4873 {
4874 struct buffer *save_current = current_buffer;
4875 current_buffer = nextb;
4876 make_gap (-(nextb->text->gap_size - size));
4877 current_buffer = save_current;
4878 }
4879 }
4880
4881 nextb = nextb->next;
4882 }
4883 }
4884
4885 EMACS_GET_TIME (t1);
4886
4887 /* In case user calls debug_print during GC,
4888 don't let that cause a recursive GC. */
4889 consing_since_gc = 0;
4890
4891 /* Save what's currently displayed in the echo area. */
4892 message_p = push_message ();
4893 record_unwind_protect (pop_message_unwind, Qnil);
4894
4895 /* Save a copy of the contents of the stack, for debugging. */
4896 #if MAX_SAVE_STACK > 0
4897 if (NILP (Vpurify_flag))
4898 {
4899 i = &stack_top_variable - stack_bottom;
4900 if (i < 0) i = -i;
4901 if (i < MAX_SAVE_STACK)
4902 {
4903 if (stack_copy == 0)
4904 stack_copy = (char *) xmalloc (stack_copy_size = i);
4905 else if (stack_copy_size < i)
4906 stack_copy = (char *) xrealloc (stack_copy, (stack_copy_size = i));
4907 if (stack_copy)
4908 {
4909 if ((EMACS_INT) (&stack_top_variable - stack_bottom) > 0)
4910 bcopy (stack_bottom, stack_copy, i);
4911 else
4912 bcopy (&stack_top_variable, stack_copy, i);
4913 }
4914 }
4915 }
4916 #endif /* MAX_SAVE_STACK > 0 */
4917
4918 if (garbage_collection_messages)
4919 message1_nolog ("Garbage collecting...");
4920
4921 BLOCK_INPUT;
4922
4923 shrink_regexp_cache ();
4924
4925 gc_in_progress = 1;
4926
4927 /* clear_marks (); */
4928
4929 /* Mark all the special slots that serve as the roots of accessibility. */
4930
4931 for (i = 0; i < staticidx; i++)
4932 mark_object (*staticvec[i]);
4933
4934 for (bind = specpdl; bind != specpdl_ptr; bind++)
4935 {
4936 mark_object (bind->symbol);
4937 mark_object (bind->old_value);
4938 }
4939 mark_kboards ();
4940
4941 #ifdef USE_GTK
4942 {
4943 extern void xg_mark_data ();
4944 xg_mark_data ();
4945 }
4946 #endif
4947
4948 #if (GC_MARK_STACK == GC_MAKE_GCPROS_NOOPS \
4949 || GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS)
4950 mark_stack ();
4951 #else
4952 {
4953 register struct gcpro *tail;
4954 for (tail = gcprolist; tail; tail = tail->next)
4955 for (i = 0; i < tail->nvars; i++)
4956 mark_object (tail->var[i]);
4957 }
4958 #endif
4959
4960 mark_byte_stack ();
4961 for (catch = catchlist; catch; catch = catch->next)
4962 {
4963 mark_object (catch->tag);
4964 mark_object (catch->val);
4965 }
4966 for (handler = handlerlist; handler; handler = handler->next)
4967 {
4968 mark_object (handler->handler);
4969 mark_object (handler->var);
4970 }
4971 mark_backtrace ();
4972
4973 #ifdef HAVE_WINDOW_SYSTEM
4974 mark_fringe_data ();
4975 #endif
4976
4977 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
4978 mark_stack ();
4979 #endif
4980
4981 /* Everything is now marked, except for the things that require special
4982 finalization, i.e. the undo_list.
4983 Look thru every buffer's undo list
4984 for elements that update markers that were not marked,
4985 and delete them. */
4986 {
4987 register struct buffer *nextb = all_buffers;
4988
4989 while (nextb)
4990 {
4991 /* If a buffer's undo list is Qt, that means that undo is
4992 turned off in that buffer. Calling truncate_undo_list on
4993 Qt tends to return NULL, which effectively turns undo back on.
4994 So don't call truncate_undo_list if undo_list is Qt. */
4995 if (! EQ (nextb->undo_list, Qt))
4996 {
4997 Lisp_Object tail, prev;
4998 tail = nextb->undo_list;
4999 prev = Qnil;
5000 while (CONSP (tail))
5001 {
5002 if (GC_CONSP (XCAR (tail))
5003 && GC_MARKERP (XCAR (XCAR (tail)))
5004 && !XMARKER (XCAR (XCAR (tail)))->gcmarkbit)
5005 {
5006 if (NILP (prev))
5007 nextb->undo_list = tail = XCDR (tail);
5008 else
5009 {
5010 tail = XCDR (tail);
5011 XSETCDR (prev, tail);
5012 }
5013 }
5014 else
5015 {
5016 prev = tail;
5017 tail = XCDR (tail);
5018 }
5019 }
5020 }
5021 /* Now that we have stripped the elements that need not be in the
5022 undo_list any more, we can finally mark the list. */
5023 mark_object (nextb->undo_list);
5024
5025 nextb = nextb->next;
5026 }
5027 }
5028
5029 gc_sweep ();
5030
5031 /* Clear the mark bits that we set in certain root slots. */
5032
5033 unmark_byte_stack ();
5034 VECTOR_UNMARK (&buffer_defaults);
5035 VECTOR_UNMARK (&buffer_local_symbols);
5036
5037 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES && 0
5038 dump_zombies ();
5039 #endif
5040
5041 UNBLOCK_INPUT;
5042
5043 CHECK_CONS_LIST ();
5044
5045 /* clear_marks (); */
5046 gc_in_progress = 0;
5047
5048 consing_since_gc = 0;
5049 if (gc_cons_threshold < 10000)
5050 gc_cons_threshold = 10000;
5051
5052 if (FLOATP (Vgc_cons_percentage))
5053 { /* Set gc_cons_combined_threshold. */
5054 EMACS_INT total = 0;
5055
5056 total += total_conses * sizeof (struct Lisp_Cons);
5057 total += total_symbols * sizeof (struct Lisp_Symbol);
5058 total += total_markers * sizeof (union Lisp_Misc);
5059 total += total_string_size;
5060 total += total_vector_size * sizeof (Lisp_Object);
5061 total += total_floats * sizeof (struct Lisp_Float);
5062 total += total_intervals * sizeof (struct interval);
5063 total += total_strings * sizeof (struct Lisp_String);
5064
5065 gc_relative_threshold = total * XFLOAT_DATA (Vgc_cons_percentage);
5066 }
5067 else
5068 gc_relative_threshold = 0;
5069
5070 if (garbage_collection_messages)
5071 {
5072 if (message_p || minibuf_level > 0)
5073 restore_message ();
5074 else
5075 message1_nolog ("Garbage collecting...done");
5076 }
5077
5078 unbind_to (count, Qnil);
5079
5080 total[0] = Fcons (make_number (total_conses),
5081 make_number (total_free_conses));
5082 total[1] = Fcons (make_number (total_symbols),
5083 make_number (total_free_symbols));
5084 total[2] = Fcons (make_number (total_markers),
5085 make_number (total_free_markers));
5086 total[3] = make_number (total_string_size);
5087 total[4] = make_number (total_vector_size);
5088 total[5] = Fcons (make_number (total_floats),
5089 make_number (total_free_floats));
5090 total[6] = Fcons (make_number (total_intervals),
5091 make_number (total_free_intervals));
5092 total[7] = Fcons (make_number (total_strings),
5093 make_number (total_free_strings));
5094
5095 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
5096 {
5097 /* Compute average percentage of zombies. */
5098 double nlive = 0;
5099
5100 for (i = 0; i < 7; ++i)
5101 if (CONSP (total[i]))
5102 nlive += XFASTINT (XCAR (total[i]));
5103
5104 avg_live = (avg_live * ngcs + nlive) / (ngcs + 1);
5105 max_live = max (nlive, max_live);
5106 avg_zombies = (avg_zombies * ngcs + nzombies) / (ngcs + 1);
5107 max_zombies = max (nzombies, max_zombies);
5108 ++ngcs;
5109 }
5110 #endif
5111
5112 if (!NILP (Vpost_gc_hook))
5113 {
5114 int count = inhibit_garbage_collection ();
5115 safe_run_hooks (Qpost_gc_hook);
5116 unbind_to (count, Qnil);
5117 }
5118
5119 /* Accumulate statistics. */
5120 EMACS_GET_TIME (t2);
5121 EMACS_SUB_TIME (t3, t2, t1);
5122 if (FLOATP (Vgc_elapsed))
5123 Vgc_elapsed = make_float (XFLOAT_DATA (Vgc_elapsed) +
5124 EMACS_SECS (t3) +
5125 EMACS_USECS (t3) * 1.0e-6);
5126 gcs_done++;
5127
5128 return Flist (sizeof total / sizeof *total, total);
5129 }
5130
5131
5132 /* Mark Lisp objects in glyph matrix MATRIX. Currently the
5133 only interesting objects referenced from glyphs are strings. */
5134
5135 static void
5136 mark_glyph_matrix (matrix)
5137 struct glyph_matrix *matrix;
5138 {
5139 struct glyph_row *row = matrix->rows;
5140 struct glyph_row *end = row + matrix->nrows;
5141
5142 for (; row < end; ++row)
5143 if (row->enabled_p)
5144 {
5145 int area;
5146 for (area = LEFT_MARGIN_AREA; area < LAST_AREA; ++area)
5147 {
5148 struct glyph *glyph = row->glyphs[area];
5149 struct glyph *end_glyph = glyph + row->used[area];
5150
5151 for (; glyph < end_glyph; ++glyph)
5152 if (GC_STRINGP (glyph->object)
5153 && !STRING_MARKED_P (XSTRING (glyph->object)))
5154 mark_object (glyph->object);
5155 }
5156 }
5157 }
5158
5159
5160 /* Mark Lisp faces in the face cache C. */
5161
5162 static void
5163 mark_face_cache (c)
5164 struct face_cache *c;
5165 {
5166 if (c)
5167 {
5168 int i, j;
5169 for (i = 0; i < c->used; ++i)
5170 {
5171 struct face *face = FACE_FROM_ID (c->f, i);
5172
5173 if (face)
5174 {
5175 for (j = 0; j < LFACE_VECTOR_SIZE; ++j)
5176 mark_object (face->lface[j]);
5177 }
5178 }
5179 }
5180 }
5181
5182
5183 #ifdef HAVE_WINDOW_SYSTEM
5184
5185 /* Mark Lisp objects in image IMG. */
5186
5187 static void
5188 mark_image (img)
5189 struct image *img;
5190 {
5191 mark_object (img->spec);
5192
5193 if (!NILP (img->data.lisp_val))
5194 mark_object (img->data.lisp_val);
5195 }
5196
5197
5198 /* Mark Lisp objects in image cache of frame F. It's done this way so
5199 that we don't have to include xterm.h here. */
5200
5201 static void
5202 mark_image_cache (f)
5203 struct frame *f;
5204 {
5205 forall_images_in_image_cache (f, mark_image);
5206 }
5207
5208 #endif /* HAVE_X_WINDOWS */
5209
5210
5211 \f
5212 /* Mark reference to a Lisp_Object.
5213 If the object referred to has not been seen yet, recursively mark
5214 all the references contained in it. */
5215
5216 #define LAST_MARKED_SIZE 500
5217 Lisp_Object last_marked[LAST_MARKED_SIZE];
5218 int last_marked_index;
5219
5220 /* For debugging--call abort when we cdr down this many
5221 links of a list, in mark_object. In debugging,
5222 the call to abort will hit a breakpoint.
5223 Normally this is zero and the check never goes off. */
5224 int mark_object_loop_halt;
5225
5226 void
5227 mark_object (arg)
5228 Lisp_Object arg;
5229 {
5230 register Lisp_Object obj = arg;
5231 #ifdef GC_CHECK_MARKED_OBJECTS
5232 void *po;
5233 struct mem_node *m;
5234 #endif
5235 int cdr_count = 0;
5236
5237 loop:
5238
5239 if (PURE_POINTER_P (XPNTR (obj)))
5240 return;
5241
5242 last_marked[last_marked_index++] = obj;
5243 if (last_marked_index == LAST_MARKED_SIZE)
5244 last_marked_index = 0;
5245
5246 /* Perform some sanity checks on the objects marked here. Abort if
5247 we encounter an object we know is bogus. This increases GC time
5248 by ~80%, and requires compilation with GC_MARK_STACK != 0. */
5249 #ifdef GC_CHECK_MARKED_OBJECTS
5250
5251 po = (void *) XPNTR (obj);
5252
5253 /* Check that the object pointed to by PO is known to be a Lisp
5254 structure allocated from the heap. */
5255 #define CHECK_ALLOCATED() \
5256 do { \
5257 m = mem_find (po); \
5258 if (m == MEM_NIL) \
5259 abort (); \
5260 } while (0)
5261
5262 /* Check that the object pointed to by PO is live, using predicate
5263 function LIVEP. */
5264 #define CHECK_LIVE(LIVEP) \
5265 do { \
5266 if (!LIVEP (m, po)) \
5267 abort (); \
5268 } while (0)
5269
5270 /* Check both of the above conditions. */
5271 #define CHECK_ALLOCATED_AND_LIVE(LIVEP) \
5272 do { \
5273 CHECK_ALLOCATED (); \
5274 CHECK_LIVE (LIVEP); \
5275 } while (0) \
5276
5277 #else /* not GC_CHECK_MARKED_OBJECTS */
5278
5279 #define CHECK_ALLOCATED() (void) 0
5280 #define CHECK_LIVE(LIVEP) (void) 0
5281 #define CHECK_ALLOCATED_AND_LIVE(LIVEP) (void) 0
5282
5283 #endif /* not GC_CHECK_MARKED_OBJECTS */
5284
5285 switch (SWITCH_ENUM_CAST (XGCTYPE (obj)))
5286 {
5287 case Lisp_String:
5288 {
5289 register struct Lisp_String *ptr = XSTRING (obj);
5290 CHECK_ALLOCATED_AND_LIVE (live_string_p);
5291 MARK_INTERVAL_TREE (ptr->intervals);
5292 MARK_STRING (ptr);
5293 #ifdef GC_CHECK_STRING_BYTES
5294 /* Check that the string size recorded in the string is the
5295 same as the one recorded in the sdata structure. */
5296 CHECK_STRING_BYTES (ptr);
5297 #endif /* GC_CHECK_STRING_BYTES */
5298 }
5299 break;
5300
5301 case Lisp_Vectorlike:
5302 #ifdef GC_CHECK_MARKED_OBJECTS
5303 m = mem_find (po);
5304 if (m == MEM_NIL && !GC_SUBRP (obj)
5305 && po != &buffer_defaults
5306 && po != &buffer_local_symbols)
5307 abort ();
5308 #endif /* GC_CHECK_MARKED_OBJECTS */
5309
5310 if (GC_BUFFERP (obj))
5311 {
5312 if (!VECTOR_MARKED_P (XBUFFER (obj)))
5313 {
5314 #ifdef GC_CHECK_MARKED_OBJECTS
5315 if (po != &buffer_defaults && po != &buffer_local_symbols)
5316 {
5317 struct buffer *b;
5318 for (b = all_buffers; b && b != po; b = b->next)
5319 ;
5320 if (b == NULL)
5321 abort ();
5322 }
5323 #endif /* GC_CHECK_MARKED_OBJECTS */
5324 mark_buffer (obj);
5325 }
5326 }
5327 else if (GC_SUBRP (obj))
5328 break;
5329 else if (GC_COMPILEDP (obj))
5330 /* We could treat this just like a vector, but it is better to
5331 save the COMPILED_CONSTANTS element for last and avoid
5332 recursion there. */
5333 {
5334 register struct Lisp_Vector *ptr = XVECTOR (obj);
5335 register EMACS_INT size = ptr->size;
5336 register int i;
5337
5338 if (VECTOR_MARKED_P (ptr))
5339 break; /* Already marked */
5340
5341 CHECK_LIVE (live_vector_p);
5342 VECTOR_MARK (ptr); /* Else mark it */
5343 size &= PSEUDOVECTOR_SIZE_MASK;
5344 for (i = 0; i < size; i++) /* and then mark its elements */
5345 {
5346 if (i != COMPILED_CONSTANTS)
5347 mark_object (ptr->contents[i]);
5348 }
5349 obj = ptr->contents[COMPILED_CONSTANTS];
5350 goto loop;
5351 }
5352 else if (GC_FRAMEP (obj))
5353 {
5354 register struct frame *ptr = XFRAME (obj);
5355
5356 if (VECTOR_MARKED_P (ptr)) break; /* Already marked */
5357 VECTOR_MARK (ptr); /* Else mark it */
5358
5359 CHECK_LIVE (live_vector_p);
5360 mark_object (ptr->name);
5361 mark_object (ptr->icon_name);
5362 mark_object (ptr->title);
5363 mark_object (ptr->focus_frame);
5364 mark_object (ptr->selected_window);
5365 mark_object (ptr->minibuffer_window);
5366 mark_object (ptr->param_alist);
5367 mark_object (ptr->scroll_bars);
5368 mark_object (ptr->condemned_scroll_bars);
5369 mark_object (ptr->menu_bar_items);
5370 mark_object (ptr->face_alist);
5371 mark_object (ptr->menu_bar_vector);
5372 mark_object (ptr->buffer_predicate);
5373 mark_object (ptr->buffer_list);
5374 mark_object (ptr->menu_bar_window);
5375 mark_object (ptr->tool_bar_window);
5376 mark_face_cache (ptr->face_cache);
5377 #ifdef HAVE_WINDOW_SYSTEM
5378 mark_image_cache (ptr);
5379 mark_object (ptr->tool_bar_items);
5380 mark_object (ptr->desired_tool_bar_string);
5381 mark_object (ptr->current_tool_bar_string);
5382 #endif /* HAVE_WINDOW_SYSTEM */
5383 }
5384 else if (GC_BOOL_VECTOR_P (obj))
5385 {
5386 register struct Lisp_Vector *ptr = XVECTOR (obj);
5387
5388 if (VECTOR_MARKED_P (ptr))
5389 break; /* Already marked */
5390 CHECK_LIVE (live_vector_p);
5391 VECTOR_MARK (ptr); /* Else mark it */
5392 }
5393 else if (GC_WINDOWP (obj))
5394 {
5395 register struct Lisp_Vector *ptr = XVECTOR (obj);
5396 struct window *w = XWINDOW (obj);
5397 register int i;
5398
5399 /* Stop if already marked. */
5400 if (VECTOR_MARKED_P (ptr))
5401 break;
5402
5403 /* Mark it. */
5404 CHECK_LIVE (live_vector_p);
5405 VECTOR_MARK (ptr);
5406
5407 /* There is no Lisp data above The member CURRENT_MATRIX in
5408 struct WINDOW. Stop marking when that slot is reached. */
5409 for (i = 0;
5410 (char *) &ptr->contents[i] < (char *) &w->current_matrix;
5411 i++)
5412 mark_object (ptr->contents[i]);
5413
5414 /* Mark glyphs for leaf windows. Marking window matrices is
5415 sufficient because frame matrices use the same glyph
5416 memory. */
5417 if (NILP (w->hchild)
5418 && NILP (w->vchild)
5419 && w->current_matrix)
5420 {
5421 mark_glyph_matrix (w->current_matrix);
5422 mark_glyph_matrix (w->desired_matrix);
5423 }
5424 }
5425 else if (GC_HASH_TABLE_P (obj))
5426 {
5427 struct Lisp_Hash_Table *h = XHASH_TABLE (obj);
5428
5429 /* Stop if already marked. */
5430 if (VECTOR_MARKED_P (h))
5431 break;
5432
5433 /* Mark it. */
5434 CHECK_LIVE (live_vector_p);
5435 VECTOR_MARK (h);
5436
5437 /* Mark contents. */
5438 /* Do not mark next_free or next_weak.
5439 Being in the next_weak chain
5440 should not keep the hash table alive.
5441 No need to mark `count' since it is an integer. */
5442 mark_object (h->test);
5443 mark_object (h->weak);
5444 mark_object (h->rehash_size);
5445 mark_object (h->rehash_threshold);
5446 mark_object (h->hash);
5447 mark_object (h->next);
5448 mark_object (h->index);
5449 mark_object (h->user_hash_function);
5450 mark_object (h->user_cmp_function);
5451
5452 /* If hash table is not weak, mark all keys and values.
5453 For weak tables, mark only the vector. */
5454 if (GC_NILP (h->weak))
5455 mark_object (h->key_and_value);
5456 else
5457 VECTOR_MARK (XVECTOR (h->key_and_value));
5458 }
5459 else
5460 {
5461 register struct Lisp_Vector *ptr = XVECTOR (obj);
5462 register EMACS_INT size = ptr->size;
5463 register int i;
5464
5465 if (VECTOR_MARKED_P (ptr)) break; /* Already marked */
5466 CHECK_LIVE (live_vector_p);
5467 VECTOR_MARK (ptr); /* Else mark it */
5468 if (size & PSEUDOVECTOR_FLAG)
5469 size &= PSEUDOVECTOR_SIZE_MASK;
5470
5471 for (i = 0; i < size; i++) /* and then mark its elements */
5472 mark_object (ptr->contents[i]);
5473 }
5474 break;
5475
5476 case Lisp_Symbol:
5477 {
5478 register struct Lisp_Symbol *ptr = XSYMBOL (obj);
5479 struct Lisp_Symbol *ptrx;
5480
5481 if (ptr->gcmarkbit) break;
5482 CHECK_ALLOCATED_AND_LIVE (live_symbol_p);
5483 ptr->gcmarkbit = 1;
5484 mark_object (ptr->value);
5485 mark_object (ptr->function);
5486 mark_object (ptr->plist);
5487
5488 if (!PURE_POINTER_P (XSTRING (ptr->xname)))
5489 MARK_STRING (XSTRING (ptr->xname));
5490 MARK_INTERVAL_TREE (STRING_INTERVALS (ptr->xname));
5491
5492 /* Note that we do not mark the obarray of the symbol.
5493 It is safe not to do so because nothing accesses that
5494 slot except to check whether it is nil. */
5495 ptr = ptr->next;
5496 if (ptr)
5497 {
5498 ptrx = ptr; /* Use of ptrx avoids compiler bug on Sun */
5499 XSETSYMBOL (obj, ptrx);
5500 goto loop;
5501 }
5502 }
5503 break;
5504
5505 case Lisp_Misc:
5506 CHECK_ALLOCATED_AND_LIVE (live_misc_p);
5507 if (XMARKER (obj)->gcmarkbit)
5508 break;
5509 XMARKER (obj)->gcmarkbit = 1;
5510
5511 switch (XMISCTYPE (obj))
5512 {
5513 case Lisp_Misc_Buffer_Local_Value:
5514 case Lisp_Misc_Some_Buffer_Local_Value:
5515 {
5516 register struct Lisp_Buffer_Local_Value *ptr
5517 = XBUFFER_LOCAL_VALUE (obj);
5518 /* If the cdr is nil, avoid recursion for the car. */
5519 if (EQ (ptr->cdr, Qnil))
5520 {
5521 obj = ptr->realvalue;
5522 goto loop;
5523 }
5524 mark_object (ptr->realvalue);
5525 mark_object (ptr->buffer);
5526 mark_object (ptr->frame);
5527 obj = ptr->cdr;
5528 goto loop;
5529 }
5530
5531 case Lisp_Misc_Marker:
5532 /* DO NOT mark thru the marker's chain.
5533 The buffer's markers chain does not preserve markers from gc;
5534 instead, markers are removed from the chain when freed by gc. */
5535 break;
5536
5537 case Lisp_Misc_Intfwd:
5538 case Lisp_Misc_Boolfwd:
5539 case Lisp_Misc_Objfwd:
5540 case Lisp_Misc_Buffer_Objfwd:
5541 case Lisp_Misc_Kboard_Objfwd:
5542 /* Don't bother with Lisp_Buffer_Objfwd,
5543 since all markable slots in current buffer marked anyway. */
5544 /* Don't need to do Lisp_Objfwd, since the places they point
5545 are protected with staticpro. */
5546 break;
5547
5548 case Lisp_Misc_Save_Value:
5549 #if GC_MARK_STACK
5550 {
5551 register struct Lisp_Save_Value *ptr = XSAVE_VALUE (obj);
5552 /* If DOGC is set, POINTER is the address of a memory
5553 area containing INTEGER potential Lisp_Objects. */
5554 if (ptr->dogc)
5555 {
5556 Lisp_Object *p = (Lisp_Object *) ptr->pointer;
5557 int nelt;
5558 for (nelt = ptr->integer; nelt > 0; nelt--, p++)
5559 mark_maybe_object (*p);
5560 }
5561 }
5562 #endif
5563 break;
5564
5565 case Lisp_Misc_Overlay:
5566 {
5567 struct Lisp_Overlay *ptr = XOVERLAY (obj);
5568 mark_object (ptr->start);
5569 mark_object (ptr->end);
5570 mark_object (ptr->plist);
5571 if (ptr->next)
5572 {
5573 XSETMISC (obj, ptr->next);
5574 goto loop;
5575 }
5576 }
5577 break;
5578
5579 default:
5580 abort ();
5581 }
5582 break;
5583
5584 case Lisp_Cons:
5585 {
5586 register struct Lisp_Cons *ptr = XCONS (obj);
5587 if (CONS_MARKED_P (ptr)) break;
5588 CHECK_ALLOCATED_AND_LIVE (live_cons_p);
5589 CONS_MARK (ptr);
5590 /* If the cdr is nil, avoid recursion for the car. */
5591 if (EQ (ptr->u.cdr, Qnil))
5592 {
5593 obj = ptr->car;
5594 cdr_count = 0;
5595 goto loop;
5596 }
5597 mark_object (ptr->car);
5598 obj = ptr->u.cdr;
5599 cdr_count++;
5600 if (cdr_count == mark_object_loop_halt)
5601 abort ();
5602 goto loop;
5603 }
5604
5605 case Lisp_Float:
5606 CHECK_ALLOCATED_AND_LIVE (live_float_p);
5607 FLOAT_MARK (XFLOAT (obj));
5608 break;
5609
5610 case Lisp_Int:
5611 break;
5612
5613 default:
5614 abort ();
5615 }
5616
5617 #undef CHECK_LIVE
5618 #undef CHECK_ALLOCATED
5619 #undef CHECK_ALLOCATED_AND_LIVE
5620 }
5621
5622 /* Mark the pointers in a buffer structure. */
5623
5624 static void
5625 mark_buffer (buf)
5626 Lisp_Object buf;
5627 {
5628 register struct buffer *buffer = XBUFFER (buf);
5629 register Lisp_Object *ptr, tmp;
5630 Lisp_Object base_buffer;
5631
5632 VECTOR_MARK (buffer);
5633
5634 MARK_INTERVAL_TREE (BUF_INTERVALS (buffer));
5635
5636 /* For now, we just don't mark the undo_list. It's done later in
5637 a special way just before the sweep phase, and after stripping
5638 some of its elements that are not needed any more. */
5639
5640 if (buffer->overlays_before)
5641 {
5642 XSETMISC (tmp, buffer->overlays_before);
5643 mark_object (tmp);
5644 }
5645 if (buffer->overlays_after)
5646 {
5647 XSETMISC (tmp, buffer->overlays_after);
5648 mark_object (tmp);
5649 }
5650
5651 for (ptr = &buffer->name;
5652 (char *)ptr < (char *)buffer + sizeof (struct buffer);
5653 ptr++)
5654 mark_object (*ptr);
5655
5656 /* If this is an indirect buffer, mark its base buffer. */
5657 if (buffer->base_buffer && !VECTOR_MARKED_P (buffer->base_buffer))
5658 {
5659 XSETBUFFER (base_buffer, buffer->base_buffer);
5660 mark_buffer (base_buffer);
5661 }
5662 }
5663
5664
5665 /* Value is non-zero if OBJ will survive the current GC because it's
5666 either marked or does not need to be marked to survive. */
5667
5668 int
5669 survives_gc_p (obj)
5670 Lisp_Object obj;
5671 {
5672 int survives_p;
5673
5674 switch (XGCTYPE (obj))
5675 {
5676 case Lisp_Int:
5677 survives_p = 1;
5678 break;
5679
5680 case Lisp_Symbol:
5681 survives_p = XSYMBOL (obj)->gcmarkbit;
5682 break;
5683
5684 case Lisp_Misc:
5685 survives_p = XMARKER (obj)->gcmarkbit;
5686 break;
5687
5688 case Lisp_String:
5689 survives_p = STRING_MARKED_P (XSTRING (obj));
5690 break;
5691
5692 case Lisp_Vectorlike:
5693 survives_p = GC_SUBRP (obj) || VECTOR_MARKED_P (XVECTOR (obj));
5694 break;
5695
5696 case Lisp_Cons:
5697 survives_p = CONS_MARKED_P (XCONS (obj));
5698 break;
5699
5700 case Lisp_Float:
5701 survives_p = FLOAT_MARKED_P (XFLOAT (obj));
5702 break;
5703
5704 default:
5705 abort ();
5706 }
5707
5708 return survives_p || PURE_POINTER_P ((void *) XPNTR (obj));
5709 }
5710
5711
5712 \f
5713 /* Sweep: find all structures not marked, and free them. */
5714
5715 static void
5716 gc_sweep ()
5717 {
5718 /* Remove or mark entries in weak hash tables.
5719 This must be done before any object is unmarked. */
5720 sweep_weak_hash_tables ();
5721
5722 sweep_strings ();
5723 #ifdef GC_CHECK_STRING_BYTES
5724 if (!noninteractive)
5725 check_string_bytes (1);
5726 #endif
5727
5728 /* Put all unmarked conses on free list */
5729 {
5730 register struct cons_block *cblk;
5731 struct cons_block **cprev = &cons_block;
5732 register int lim = cons_block_index;
5733 register int num_free = 0, num_used = 0;
5734
5735 cons_free_list = 0;
5736
5737 for (cblk = cons_block; cblk; cblk = *cprev)
5738 {
5739 register int i;
5740 int this_free = 0;
5741 for (i = 0; i < lim; i++)
5742 if (!CONS_MARKED_P (&cblk->conses[i]))
5743 {
5744 this_free++;
5745 cblk->conses[i].u.chain = cons_free_list;
5746 cons_free_list = &cblk->conses[i];
5747 #if GC_MARK_STACK
5748 cons_free_list->car = Vdead;
5749 #endif
5750 }
5751 else
5752 {
5753 num_used++;
5754 CONS_UNMARK (&cblk->conses[i]);
5755 }
5756 lim = CONS_BLOCK_SIZE;
5757 /* If this block contains only free conses and we have already
5758 seen more than two blocks worth of free conses then deallocate
5759 this block. */
5760 if (this_free == CONS_BLOCK_SIZE && num_free > CONS_BLOCK_SIZE)
5761 {
5762 *cprev = cblk->next;
5763 /* Unhook from the free list. */
5764 cons_free_list = cblk->conses[0].u.chain;
5765 lisp_align_free (cblk);
5766 n_cons_blocks--;
5767 }
5768 else
5769 {
5770 num_free += this_free;
5771 cprev = &cblk->next;
5772 }
5773 }
5774 total_conses = num_used;
5775 total_free_conses = num_free;
5776 }
5777
5778 /* Put all unmarked floats on free list */
5779 {
5780 register struct float_block *fblk;
5781 struct float_block **fprev = &float_block;
5782 register int lim = float_block_index;
5783 register int num_free = 0, num_used = 0;
5784
5785 float_free_list = 0;
5786
5787 for (fblk = float_block; fblk; fblk = *fprev)
5788 {
5789 register int i;
5790 int this_free = 0;
5791 for (i = 0; i < lim; i++)
5792 if (!FLOAT_MARKED_P (&fblk->floats[i]))
5793 {
5794 this_free++;
5795 fblk->floats[i].u.chain = float_free_list;
5796 float_free_list = &fblk->floats[i];
5797 }
5798 else
5799 {
5800 num_used++;
5801 FLOAT_UNMARK (&fblk->floats[i]);
5802 }
5803 lim = FLOAT_BLOCK_SIZE;
5804 /* If this block contains only free floats and we have already
5805 seen more than two blocks worth of free floats then deallocate
5806 this block. */
5807 if (this_free == FLOAT_BLOCK_SIZE && num_free > FLOAT_BLOCK_SIZE)
5808 {
5809 *fprev = fblk->next;
5810 /* Unhook from the free list. */
5811 float_free_list = fblk->floats[0].u.chain;
5812 lisp_align_free (fblk);
5813 n_float_blocks--;
5814 }
5815 else
5816 {
5817 num_free += this_free;
5818 fprev = &fblk->next;
5819 }
5820 }
5821 total_floats = num_used;
5822 total_free_floats = num_free;
5823 }
5824
5825 /* Put all unmarked intervals on free list */
5826 {
5827 register struct interval_block *iblk;
5828 struct interval_block **iprev = &interval_block;
5829 register int lim = interval_block_index;
5830 register int num_free = 0, num_used = 0;
5831
5832 interval_free_list = 0;
5833
5834 for (iblk = interval_block; iblk; iblk = *iprev)
5835 {
5836 register int i;
5837 int this_free = 0;
5838
5839 for (i = 0; i < lim; i++)
5840 {
5841 if (!iblk->intervals[i].gcmarkbit)
5842 {
5843 SET_INTERVAL_PARENT (&iblk->intervals[i], interval_free_list);
5844 interval_free_list = &iblk->intervals[i];
5845 this_free++;
5846 }
5847 else
5848 {
5849 num_used++;
5850 iblk->intervals[i].gcmarkbit = 0;
5851 }
5852 }
5853 lim = INTERVAL_BLOCK_SIZE;
5854 /* If this block contains only free intervals and we have already
5855 seen more than two blocks worth of free intervals then
5856 deallocate this block. */
5857 if (this_free == INTERVAL_BLOCK_SIZE && num_free > INTERVAL_BLOCK_SIZE)
5858 {
5859 *iprev = iblk->next;
5860 /* Unhook from the free list. */
5861 interval_free_list = INTERVAL_PARENT (&iblk->intervals[0]);
5862 lisp_free (iblk);
5863 n_interval_blocks--;
5864 }
5865 else
5866 {
5867 num_free += this_free;
5868 iprev = &iblk->next;
5869 }
5870 }
5871 total_intervals = num_used;
5872 total_free_intervals = num_free;
5873 }
5874
5875 /* Put all unmarked symbols on free list */
5876 {
5877 register struct symbol_block *sblk;
5878 struct symbol_block **sprev = &symbol_block;
5879 register int lim = symbol_block_index;
5880 register int num_free = 0, num_used = 0;
5881
5882 symbol_free_list = NULL;
5883
5884 for (sblk = symbol_block; sblk; sblk = *sprev)
5885 {
5886 int this_free = 0;
5887 struct Lisp_Symbol *sym = sblk->symbols;
5888 struct Lisp_Symbol *end = sym + lim;
5889
5890 for (; sym < end; ++sym)
5891 {
5892 /* Check if the symbol was created during loadup. In such a case
5893 it might be pointed to by pure bytecode which we don't trace,
5894 so we conservatively assume that it is live. */
5895 int pure_p = PURE_POINTER_P (XSTRING (sym->xname));
5896
5897 if (!sym->gcmarkbit && !pure_p)
5898 {
5899 sym->next = symbol_free_list;
5900 symbol_free_list = sym;
5901 #if GC_MARK_STACK
5902 symbol_free_list->function = Vdead;
5903 #endif
5904 ++this_free;
5905 }
5906 else
5907 {
5908 ++num_used;
5909 if (!pure_p)
5910 UNMARK_STRING (XSTRING (sym->xname));
5911 sym->gcmarkbit = 0;
5912 }
5913 }
5914
5915 lim = SYMBOL_BLOCK_SIZE;
5916 /* If this block contains only free symbols and we have already
5917 seen more than two blocks worth of free symbols then deallocate
5918 this block. */
5919 if (this_free == SYMBOL_BLOCK_SIZE && num_free > SYMBOL_BLOCK_SIZE)
5920 {
5921 *sprev = sblk->next;
5922 /* Unhook from the free list. */
5923 symbol_free_list = sblk->symbols[0].next;
5924 lisp_free (sblk);
5925 n_symbol_blocks--;
5926 }
5927 else
5928 {
5929 num_free += this_free;
5930 sprev = &sblk->next;
5931 }
5932 }
5933 total_symbols = num_used;
5934 total_free_symbols = num_free;
5935 }
5936
5937 /* Put all unmarked misc's on free list.
5938 For a marker, first unchain it from the buffer it points into. */
5939 {
5940 register struct marker_block *mblk;
5941 struct marker_block **mprev = &marker_block;
5942 register int lim = marker_block_index;
5943 register int num_free = 0, num_used = 0;
5944
5945 marker_free_list = 0;
5946
5947 for (mblk = marker_block; mblk; mblk = *mprev)
5948 {
5949 register int i;
5950 int this_free = 0;
5951
5952 for (i = 0; i < lim; i++)
5953 {
5954 if (!mblk->markers[i].u_marker.gcmarkbit)
5955 {
5956 if (mblk->markers[i].u_marker.type == Lisp_Misc_Marker)
5957 unchain_marker (&mblk->markers[i].u_marker);
5958 /* Set the type of the freed object to Lisp_Misc_Free.
5959 We could leave the type alone, since nobody checks it,
5960 but this might catch bugs faster. */
5961 mblk->markers[i].u_marker.type = Lisp_Misc_Free;
5962 mblk->markers[i].u_free.chain = marker_free_list;
5963 marker_free_list = &mblk->markers[i];
5964 this_free++;
5965 }
5966 else
5967 {
5968 num_used++;
5969 mblk->markers[i].u_marker.gcmarkbit = 0;
5970 }
5971 }
5972 lim = MARKER_BLOCK_SIZE;
5973 /* If this block contains only free markers and we have already
5974 seen more than two blocks worth of free markers then deallocate
5975 this block. */
5976 if (this_free == MARKER_BLOCK_SIZE && num_free > MARKER_BLOCK_SIZE)
5977 {
5978 *mprev = mblk->next;
5979 /* Unhook from the free list. */
5980 marker_free_list = mblk->markers[0].u_free.chain;
5981 lisp_free (mblk);
5982 n_marker_blocks--;
5983 }
5984 else
5985 {
5986 num_free += this_free;
5987 mprev = &mblk->next;
5988 }
5989 }
5990
5991 total_markers = num_used;
5992 total_free_markers = num_free;
5993 }
5994
5995 /* Free all unmarked buffers */
5996 {
5997 register struct buffer *buffer = all_buffers, *prev = 0, *next;
5998
5999 while (buffer)
6000 if (!VECTOR_MARKED_P (buffer))
6001 {
6002 if (prev)
6003 prev->next = buffer->next;
6004 else
6005 all_buffers = buffer->next;
6006 next = buffer->next;
6007 lisp_free (buffer);
6008 buffer = next;
6009 }
6010 else
6011 {
6012 VECTOR_UNMARK (buffer);
6013 UNMARK_BALANCE_INTERVALS (BUF_INTERVALS (buffer));
6014 prev = buffer, buffer = buffer->next;
6015 }
6016 }
6017
6018 /* Free all unmarked vectors */
6019 {
6020 register struct Lisp_Vector *vector = all_vectors, *prev = 0, *next;
6021 total_vector_size = 0;
6022
6023 while (vector)
6024 if (!VECTOR_MARKED_P (vector))
6025 {
6026 if (prev)
6027 prev->next = vector->next;
6028 else
6029 all_vectors = vector->next;
6030 next = vector->next;
6031 lisp_free (vector);
6032 n_vectors--;
6033 vector = next;
6034
6035 }
6036 else
6037 {
6038 VECTOR_UNMARK (vector);
6039 if (vector->size & PSEUDOVECTOR_FLAG)
6040 total_vector_size += (PSEUDOVECTOR_SIZE_MASK & vector->size);
6041 else
6042 total_vector_size += vector->size;
6043 prev = vector, vector = vector->next;
6044 }
6045 }
6046
6047 #ifdef GC_CHECK_STRING_BYTES
6048 if (!noninteractive)
6049 check_string_bytes (1);
6050 #endif
6051 }
6052
6053
6054
6055 \f
6056 /* Debugging aids. */
6057
6058 DEFUN ("memory-limit", Fmemory_limit, Smemory_limit, 0, 0, 0,
6059 doc: /* Return the address of the last byte Emacs has allocated, divided by 1024.
6060 This may be helpful in debugging Emacs's memory usage.
6061 We divide the value by 1024 to make sure it fits in a Lisp integer. */)
6062 ()
6063 {
6064 Lisp_Object end;
6065
6066 XSETINT (end, (EMACS_INT) sbrk (0) / 1024);
6067
6068 return end;
6069 }
6070
6071 DEFUN ("memory-use-counts", Fmemory_use_counts, Smemory_use_counts, 0, 0, 0,
6072 doc: /* Return a list of counters that measure how much consing there has been.
6073 Each of these counters increments for a certain kind of object.
6074 The counters wrap around from the largest positive integer to zero.
6075 Garbage collection does not decrease them.
6076 The elements of the value are as follows:
6077 (CONSES FLOATS VECTOR-CELLS SYMBOLS STRING-CHARS MISCS INTERVALS STRINGS)
6078 All are in units of 1 = one object consed
6079 except for VECTOR-CELLS and STRING-CHARS, which count the total length of
6080 objects consed.
6081 MISCS include overlays, markers, and some internal types.
6082 Frames, windows, buffers, and subprocesses count as vectors
6083 (but the contents of a buffer's text do not count here). */)
6084 ()
6085 {
6086 Lisp_Object consed[8];
6087
6088 consed[0] = make_number (min (MOST_POSITIVE_FIXNUM, cons_cells_consed));
6089 consed[1] = make_number (min (MOST_POSITIVE_FIXNUM, floats_consed));
6090 consed[2] = make_number (min (MOST_POSITIVE_FIXNUM, vector_cells_consed));
6091 consed[3] = make_number (min (MOST_POSITIVE_FIXNUM, symbols_consed));
6092 consed[4] = make_number (min (MOST_POSITIVE_FIXNUM, string_chars_consed));
6093 consed[5] = make_number (min (MOST_POSITIVE_FIXNUM, misc_objects_consed));
6094 consed[6] = make_number (min (MOST_POSITIVE_FIXNUM, intervals_consed));
6095 consed[7] = make_number (min (MOST_POSITIVE_FIXNUM, strings_consed));
6096
6097 return Flist (8, consed);
6098 }
6099
6100 int suppress_checking;
6101 void
6102 die (msg, file, line)
6103 const char *msg;
6104 const char *file;
6105 int line;
6106 {
6107 fprintf (stderr, "\r\nEmacs fatal error: %s:%d: %s\r\n",
6108 file, line, msg);
6109 abort ();
6110 }
6111 \f
6112 /* Initialization */
6113
6114 void
6115 init_alloc_once ()
6116 {
6117 /* Used to do Vpurify_flag = Qt here, but Qt isn't set up yet! */
6118 purebeg = PUREBEG;
6119 pure_size = PURESIZE;
6120 pure_bytes_used = 0;
6121 pure_bytes_used_before_overflow = 0;
6122
6123 /* Initialize the list of free aligned blocks. */
6124 free_ablock = NULL;
6125
6126 #if GC_MARK_STACK || defined GC_MALLOC_CHECK
6127 mem_init ();
6128 Vdead = make_pure_string ("DEAD", 4, 4, 0);
6129 #endif
6130
6131 all_vectors = 0;
6132 ignore_warnings = 1;
6133 #ifdef DOUG_LEA_MALLOC
6134 mallopt (M_TRIM_THRESHOLD, 128*1024); /* trim threshold */
6135 mallopt (M_MMAP_THRESHOLD, 64*1024); /* mmap threshold */
6136 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS); /* max. number of mmap'ed areas */
6137 #endif
6138 init_strings ();
6139 init_cons ();
6140 init_symbol ();
6141 init_marker ();
6142 init_float ();
6143 init_intervals ();
6144
6145 #ifdef REL_ALLOC
6146 malloc_hysteresis = 32;
6147 #else
6148 malloc_hysteresis = 0;
6149 #endif
6150
6151 refill_memory_reserve ();
6152
6153 ignore_warnings = 0;
6154 gcprolist = 0;
6155 byte_stack_list = 0;
6156 staticidx = 0;
6157 consing_since_gc = 0;
6158 gc_cons_threshold = 100000 * sizeof (Lisp_Object);
6159 gc_relative_threshold = 0;
6160
6161 #ifdef VIRT_ADDR_VARIES
6162 malloc_sbrk_unused = 1<<22; /* A large number */
6163 malloc_sbrk_used = 100000; /* as reasonable as any number */
6164 #endif /* VIRT_ADDR_VARIES */
6165 }
6166
6167 void
6168 init_alloc ()
6169 {
6170 gcprolist = 0;
6171 byte_stack_list = 0;
6172 #if GC_MARK_STACK
6173 #if !defined GC_SAVE_REGISTERS_ON_STACK && !defined GC_SETJMP_WORKS
6174 setjmp_tested_p = longjmps_done = 0;
6175 #endif
6176 #endif
6177 Vgc_elapsed = make_float (0.0);
6178 gcs_done = 0;
6179 }
6180
6181 void
6182 syms_of_alloc ()
6183 {
6184 DEFVAR_INT ("gc-cons-threshold", &gc_cons_threshold,
6185 doc: /* *Number of bytes of consing between garbage collections.
6186 Garbage collection can happen automatically once this many bytes have been
6187 allocated since the last garbage collection. All data types count.
6188
6189 Garbage collection happens automatically only when `eval' is called.
6190
6191 By binding this temporarily to a large number, you can effectively
6192 prevent garbage collection during a part of the program.
6193 See also `gc-cons-percentage'. */);
6194
6195 DEFVAR_LISP ("gc-cons-percentage", &Vgc_cons_percentage,
6196 doc: /* *Portion of the heap used for allocation.
6197 Garbage collection can happen automatically once this portion of the heap
6198 has been allocated since the last garbage collection.
6199 If this portion is smaller than `gc-cons-threshold', this is ignored. */);
6200 Vgc_cons_percentage = make_float (0.1);
6201
6202 DEFVAR_INT ("pure-bytes-used", &pure_bytes_used,
6203 doc: /* Number of bytes of sharable Lisp data allocated so far. */);
6204
6205 DEFVAR_INT ("cons-cells-consed", &cons_cells_consed,
6206 doc: /* Number of cons cells that have been consed so far. */);
6207
6208 DEFVAR_INT ("floats-consed", &floats_consed,
6209 doc: /* Number of floats that have been consed so far. */);
6210
6211 DEFVAR_INT ("vector-cells-consed", &vector_cells_consed,
6212 doc: /* Number of vector cells that have been consed so far. */);
6213
6214 DEFVAR_INT ("symbols-consed", &symbols_consed,
6215 doc: /* Number of symbols that have been consed so far. */);
6216
6217 DEFVAR_INT ("string-chars-consed", &string_chars_consed,
6218 doc: /* Number of string characters that have been consed so far. */);
6219
6220 DEFVAR_INT ("misc-objects-consed", &misc_objects_consed,
6221 doc: /* Number of miscellaneous objects that have been consed so far. */);
6222
6223 DEFVAR_INT ("intervals-consed", &intervals_consed,
6224 doc: /* Number of intervals that have been consed so far. */);
6225
6226 DEFVAR_INT ("strings-consed", &strings_consed,
6227 doc: /* Number of strings that have been consed so far. */);
6228
6229 DEFVAR_LISP ("purify-flag", &Vpurify_flag,
6230 doc: /* Non-nil means loading Lisp code in order to dump an executable.
6231 This means that certain objects should be allocated in shared (pure) space. */);
6232
6233 DEFVAR_BOOL ("garbage-collection-messages", &garbage_collection_messages,
6234 doc: /* Non-nil means display messages at start and end of garbage collection. */);
6235 garbage_collection_messages = 0;
6236
6237 DEFVAR_LISP ("post-gc-hook", &Vpost_gc_hook,
6238 doc: /* Hook run after garbage collection has finished. */);
6239 Vpost_gc_hook = Qnil;
6240 Qpost_gc_hook = intern ("post-gc-hook");
6241 staticpro (&Qpost_gc_hook);
6242
6243 DEFVAR_LISP ("memory-signal-data", &Vmemory_signal_data,
6244 doc: /* Precomputed `signal' argument for memory-full error. */);
6245 /* We build this in advance because if we wait until we need it, we might
6246 not be able to allocate the memory to hold it. */
6247 Vmemory_signal_data
6248 = list2 (Qerror,
6249 build_string ("Memory exhausted--use M-x save-some-buffers then exit and restart Emacs"));
6250
6251 DEFVAR_LISP ("memory-full", &Vmemory_full,
6252 doc: /* Non-nil means Emacs cannot get much more Lisp memory. */);
6253 Vmemory_full = Qnil;
6254
6255 staticpro (&Qgc_cons_threshold);
6256 Qgc_cons_threshold = intern ("gc-cons-threshold");
6257
6258 staticpro (&Qchar_table_extra_slots);
6259 Qchar_table_extra_slots = intern ("char-table-extra-slots");
6260
6261 DEFVAR_LISP ("gc-elapsed", &Vgc_elapsed,
6262 doc: /* Accumulated time elapsed in garbage collections.
6263 The time is in seconds as a floating point value. */);
6264 DEFVAR_INT ("gcs-done", &gcs_done,
6265 doc: /* Accumulated number of garbage collections done. */);
6266
6267 defsubr (&Scons);
6268 defsubr (&Slist);
6269 defsubr (&Svector);
6270 defsubr (&Smake_byte_code);
6271 defsubr (&Smake_list);
6272 defsubr (&Smake_vector);
6273 defsubr (&Smake_char_table);
6274 defsubr (&Smake_string);
6275 defsubr (&Smake_bool_vector);
6276 defsubr (&Smake_symbol);
6277 defsubr (&Smake_marker);
6278 defsubr (&Spurecopy);
6279 defsubr (&Sgarbage_collect);
6280 defsubr (&Smemory_limit);
6281 defsubr (&Smemory_use_counts);
6282
6283 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
6284 defsubr (&Sgc_status);
6285 #endif
6286 }
6287
6288 /* arch-tag: 6695ca10-e3c5-4c2c-8bc3-ed26a7dda857
6289 (do not change this comment) */