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[emacs.git] / src / gmalloc.c
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1 /* This file is no longer automatically generated from libc. */
3 #define _MALLOC_INTERNAL
5 /* The malloc headers and source files from the C library follow here. */
7 /* Declarations for `malloc' and friends.
8 Copyright 1990, 91, 92, 93, 95, 96 Free Software Foundation, Inc.
9 Written May 1989 by Mike Haertel.
11 This library is free software; you can redistribute it and/or
12 modify it under the terms of the GNU Library General Public License as
13 published by the Free Software Foundation; either version 2 of the
14 License, or (at your option) any later version.
16 This library is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 Library General Public License for more details.
21 You should have received a copy of the GNU Library General Public
22 License along with this library; see the file COPYING.LIB. If
23 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
24 Cambridge, MA 02139, USA.
26 The author may be reached (Email) at the address mike@ai.mit.edu,
27 or (US mail) as Mike Haertel c/o Free Software Foundation. */
29 #ifndef _MALLOC_H
31 #define _MALLOC_H 1
33 #ifdef _MALLOC_INTERNAL
35 #ifdef HAVE_CONFIG_H
36 #include <config.h>
37 #endif
39 #if defined (__cplusplus) || (defined (__STDC__) && __STDC__)
40 #undef PP
41 #define PP(args) args
42 #undef __ptr_t
43 #define __ptr_t void *
44 #else /* Not C++ or ANSI C. */
45 #undef PP
46 #define PP(args) ()
47 #undef const
48 #define const
49 #undef __ptr_t
50 #define __ptr_t char *
51 #endif /* C++ or ANSI C. */
53 #if defined(_LIBC) || defined(STDC_HEADERS) || defined(USG)
54 #include <string.h>
55 #else
56 #ifndef memset
57 #define memset(s, zero, n) bzero ((s), (n))
58 #endif
59 #ifndef memcpy
60 #define memcpy(d, s, n) bcopy ((s), (d), (n))
61 #endif
62 #endif
64 #if defined (__GNU_LIBRARY__) || (defined (__STDC__) && __STDC__)
65 #include <limits.h>
66 #else
67 #ifndef CHAR_BIT
68 #define CHAR_BIT 8
69 #endif
70 #endif
72 #ifdef HAVE_UNISTD_H
73 #include <unistd.h>
74 #endif
76 #endif /* _MALLOC_INTERNAL. */
79 #ifdef __cplusplus
80 extern "C"
82 #endif
84 #if defined (__STDC__) && __STDC__
85 #include <stddef.h>
86 #define __malloc_size_t size_t
87 #define __malloc_ptrdiff_t ptrdiff_t
88 #else
89 #define __malloc_size_t unsigned int
90 #define __malloc_ptrdiff_t int
91 #endif
93 #ifndef NULL
94 #define NULL 0
95 #endif
98 /* Allocate SIZE bytes of memory. */
99 extern __ptr_t malloc PP ((__malloc_size_t __size));
100 /* Re-allocate the previously allocated block
101 in __ptr_t, making the new block SIZE bytes long. */
102 extern __ptr_t realloc PP ((__ptr_t __ptr, __malloc_size_t __size));
103 /* Allocate NMEMB elements of SIZE bytes each, all initialized to 0. */
104 extern __ptr_t calloc PP ((__malloc_size_t __nmemb, __malloc_size_t __size));
105 /* Free a block allocated by `malloc', `realloc' or `calloc'. */
106 extern void free PP ((__ptr_t __ptr));
108 /* Allocate SIZE bytes allocated to ALIGNMENT bytes. */
109 #if ! (defined (_MALLOC_INTERNAL) && __DJGPP__ - 0 == 1) /* Avoid conflict. */
110 extern __ptr_t memalign PP ((__malloc_size_t __alignment,
111 __malloc_size_t __size));
112 #endif
114 /* Allocate SIZE bytes on a page boundary. */
115 #if ! (defined (_MALLOC_INTERNAL) && defined (GMALLOC_INHIBIT_VALLOC))
116 extern __ptr_t valloc PP ((__malloc_size_t __size));
117 #endif
120 #ifdef _MALLOC_INTERNAL
122 /* The allocator divides the heap into blocks of fixed size; large
123 requests receive one or more whole blocks, and small requests
124 receive a fragment of a block. Fragment sizes are powers of two,
125 and all fragments of a block are the same size. When all the
126 fragments in a block have been freed, the block itself is freed. */
127 #define INT_BIT (CHAR_BIT * sizeof(int))
128 #define BLOCKLOG (INT_BIT > 16 ? 12 : 9)
129 #define BLOCKSIZE (1 << BLOCKLOG)
130 #define BLOCKIFY(SIZE) (((SIZE) + BLOCKSIZE - 1) / BLOCKSIZE)
132 /* Determine the amount of memory spanned by the initial heap table
133 (not an absolute limit). */
134 #define HEAP (INT_BIT > 16 ? 4194304 : 65536)
136 /* Number of contiguous free blocks allowed to build up at the end of
137 memory before they will be returned to the system. */
138 #define FINAL_FREE_BLOCKS 8
140 /* Data structure giving per-block information. */
141 typedef union
143 /* Heap information for a busy block. */
144 struct
146 /* Zero for a large (multiblock) object, or positive giving the
147 logarithm to the base two of the fragment size. */
148 int type;
149 union
151 struct
153 __malloc_size_t nfree; /* Free frags in a fragmented block. */
154 __malloc_size_t first; /* First free fragment of the block. */
155 } frag;
156 /* For a large object, in its first block, this has the number
157 of blocks in the object. In the other blocks, this has a
158 negative number which says how far back the first block is. */
159 __malloc_ptrdiff_t size;
160 } info;
161 } busy;
162 /* Heap information for a free block
163 (that may be the first of a free cluster). */
164 struct
166 __malloc_size_t size; /* Size (in blocks) of a free cluster. */
167 __malloc_size_t next; /* Index of next free cluster. */
168 __malloc_size_t prev; /* Index of previous free cluster. */
169 } free;
170 } malloc_info;
172 /* Pointer to first block of the heap. */
173 extern char *_heapbase;
175 /* Table indexed by block number giving per-block information. */
176 extern malloc_info *_heapinfo;
178 /* Address to block number and vice versa. */
179 #define BLOCK(A) (((char *) (A) - _heapbase) / BLOCKSIZE + 1)
180 #define ADDRESS(B) ((__ptr_t) (((B) - 1) * BLOCKSIZE + _heapbase))
182 /* Current search index for the heap table. */
183 extern __malloc_size_t _heapindex;
185 /* Limit of valid info table indices. */
186 extern __malloc_size_t _heaplimit;
188 /* Doubly linked lists of free fragments. */
189 struct list
191 struct list *next;
192 struct list *prev;
195 /* Free list headers for each fragment size. */
196 extern struct list _fraghead[];
198 /* List of blocks allocated with `memalign' (or `valloc'). */
199 struct alignlist
201 struct alignlist *next;
202 __ptr_t aligned; /* The address that memaligned returned. */
203 __ptr_t exact; /* The address that malloc returned. */
205 extern struct alignlist *_aligned_blocks;
207 /* Instrumentation. */
208 extern __malloc_size_t _chunks_used;
209 extern __malloc_size_t _bytes_used;
210 extern __malloc_size_t _chunks_free;
211 extern __malloc_size_t _bytes_free;
213 /* Internal versions of `malloc', `realloc', and `free'
214 used when these functions need to call each other.
215 They are the same but don't call the hooks. */
216 extern __ptr_t _malloc_internal PP ((__malloc_size_t __size));
217 extern __ptr_t _realloc_internal PP ((__ptr_t __ptr, __malloc_size_t __size));
218 extern void _free_internal PP ((__ptr_t __ptr));
220 #endif /* _MALLOC_INTERNAL. */
222 /* Given an address in the middle of a malloc'd object,
223 return the address of the beginning of the object. */
224 extern __ptr_t malloc_find_object_address PP ((__ptr_t __ptr));
226 /* Underlying allocation function; successive calls should
227 return contiguous pieces of memory. */
228 extern __ptr_t (*__morecore) PP ((__malloc_ptrdiff_t __size));
230 /* Default value of `__morecore'. */
231 extern __ptr_t __default_morecore PP ((__malloc_ptrdiff_t __size));
233 /* If not NULL, this function is called after each time
234 `__morecore' is called to increase the data size. */
235 extern void (*__after_morecore_hook) PP ((void));
237 /* Number of extra blocks to get each time we ask for more core.
238 This reduces the frequency of calling `(*__morecore)'. */
239 extern __malloc_size_t __malloc_extra_blocks;
241 /* Nonzero if `malloc' has been called and done its initialization. */
242 extern int __malloc_initialized;
243 /* Function called to initialize malloc data structures. */
244 extern int __malloc_initialize PP ((void));
246 /* Hooks for debugging versions. */
247 extern void (*__malloc_initialize_hook) PP ((void));
248 extern void (*__free_hook) PP ((__ptr_t __ptr));
249 extern __ptr_t (*__malloc_hook) PP ((__malloc_size_t __size));
250 extern __ptr_t (*__realloc_hook) PP ((__ptr_t __ptr, __malloc_size_t __size));
251 extern __ptr_t (*__memalign_hook) PP ((__malloc_size_t __size,
252 __malloc_size_t __alignment));
254 /* Return values for `mprobe': these are the kinds of inconsistencies that
255 `mcheck' enables detection of. */
256 enum mcheck_status
258 MCHECK_DISABLED = -1, /* Consistency checking is not turned on. */
259 MCHECK_OK, /* Block is fine. */
260 MCHECK_FREE, /* Block freed twice. */
261 MCHECK_HEAD, /* Memory before the block was clobbered. */
262 MCHECK_TAIL /* Memory after the block was clobbered. */
265 /* Activate a standard collection of debugging hooks. This must be called
266 before `malloc' is ever called. ABORTFUNC is called with an error code
267 (see enum above) when an inconsistency is detected. If ABORTFUNC is
268 null, the standard function prints on stderr and then calls `abort'. */
269 extern int mcheck PP ((void (*__abortfunc) PP ((enum mcheck_status))));
271 /* Check for aberrations in a particular malloc'd block. You must have
272 called `mcheck' already. These are the same checks that `mcheck' does
273 when you free or reallocate a block. */
274 extern enum mcheck_status mprobe PP ((__ptr_t __ptr));
276 /* Activate a standard collection of tracing hooks. */
277 extern void mtrace PP ((void));
278 extern void muntrace PP ((void));
280 /* Statistics available to the user. */
281 struct mstats
283 __malloc_size_t bytes_total; /* Total size of the heap. */
284 __malloc_size_t chunks_used; /* Chunks allocated by the user. */
285 __malloc_size_t bytes_used; /* Byte total of user-allocated chunks. */
286 __malloc_size_t chunks_free; /* Chunks in the free list. */
287 __malloc_size_t bytes_free; /* Byte total of chunks in the free list. */
290 /* Pick up the current statistics. */
291 extern struct mstats mstats PP ((void));
293 /* Call WARNFUN with a warning message when memory usage is high. */
294 extern void memory_warnings PP ((__ptr_t __start,
295 void (*__warnfun) PP ((const char *))));
298 /* Relocating allocator. */
300 /* Allocate SIZE bytes, and store the address in *HANDLEPTR. */
301 extern __ptr_t r_alloc PP ((__ptr_t *__handleptr, __malloc_size_t __size));
303 /* Free the storage allocated in HANDLEPTR. */
304 extern void r_alloc_free PP ((__ptr_t *__handleptr));
306 /* Adjust the block at HANDLEPTR to be SIZE bytes long. */
307 extern __ptr_t r_re_alloc PP ((__ptr_t *__handleptr, __malloc_size_t __size));
310 #ifdef __cplusplus
312 #endif
314 #endif /* malloc.h */
315 /* Memory allocator `malloc'.
316 Copyright 1990, 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
317 Written May 1989 by Mike Haertel.
319 This library is free software; you can redistribute it and/or
320 modify it under the terms of the GNU Library General Public License as
321 published by the Free Software Foundation; either version 2 of the
322 License, or (at your option) any later version.
324 This library is distributed in the hope that it will be useful,
325 but WITHOUT ANY WARRANTY; without even the implied warranty of
326 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
327 Library General Public License for more details.
329 You should have received a copy of the GNU Library General Public
330 License along with this library; see the file COPYING.LIB. If
331 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
332 Cambridge, MA 02139, USA.
334 The author may be reached (Email) at the address mike@ai.mit.edu,
335 or (US mail) as Mike Haertel c/o Free Software Foundation. */
337 #ifndef _MALLOC_INTERNAL
338 #define _MALLOC_INTERNAL
339 #include <malloc.h>
340 #endif
341 #include <errno.h>
343 /* How to really get more memory. */
344 __ptr_t (*__morecore) PP ((ptrdiff_t __size)) = __default_morecore;
346 /* Debugging hook for `malloc'. */
347 __ptr_t (*__malloc_hook) PP ((__malloc_size_t __size));
349 /* Pointer to the base of the first block. */
350 char *_heapbase;
352 /* Block information table. Allocated with align/__free (not malloc/free). */
353 malloc_info *_heapinfo;
355 /* Number of info entries. */
356 static __malloc_size_t heapsize;
358 /* Search index in the info table. */
359 __malloc_size_t _heapindex;
361 /* Limit of valid info table indices. */
362 __malloc_size_t _heaplimit;
364 /* Free lists for each fragment size. */
365 struct list _fraghead[BLOCKLOG];
367 /* Instrumentation. */
368 __malloc_size_t _chunks_used;
369 __malloc_size_t _bytes_used;
370 __malloc_size_t _chunks_free;
371 __malloc_size_t _bytes_free;
373 /* Are you experienced? */
374 int __malloc_initialized;
376 __malloc_size_t __malloc_extra_blocks;
378 void (*__malloc_initialize_hook) PP ((void));
379 void (*__after_morecore_hook) PP ((void));
382 /* Aligned allocation. */
383 static __ptr_t align PP ((__malloc_size_t));
384 static __ptr_t
385 align (size)
386 __malloc_size_t size;
388 __ptr_t result;
389 unsigned long int adj;
391 result = (*__morecore) (size);
392 adj = (unsigned long int) ((unsigned long int) ((char *) result -
393 (char *) NULL)) % BLOCKSIZE;
394 if (adj != 0)
396 __ptr_t new;
397 adj = BLOCKSIZE - adj;
398 new = (*__morecore) (adj);
399 result = (char *) result + adj;
402 if (__after_morecore_hook)
403 (*__after_morecore_hook) ();
405 return result;
408 /* Get SIZE bytes, if we can get them starting at END.
409 Return the address of the space we got.
410 If we cannot get space at END, fail and return 0. */
411 static __ptr_t get_contiguous_space PP ((__malloc_ptrdiff_t, __ptr_t));
412 static __ptr_t
413 get_contiguous_space (size, position)
414 __malloc_ptrdiff_t size;
415 __ptr_t position;
417 __ptr_t before;
418 __ptr_t after;
420 before = (*__morecore) (0);
421 /* If we can tell in advance that the break is at the wrong place,
422 fail now. */
423 if (before != position)
424 return 0;
426 /* Allocate SIZE bytes and get the address of them. */
427 after = (*__morecore) (size);
428 if (!after)
429 return 0;
431 /* It was not contiguous--reject it. */
432 if (after != position)
434 (*__morecore) (- size);
435 return 0;
438 return after;
442 /* This is called when `_heapinfo' and `heapsize' have just
443 been set to describe a new info table. Set up the table
444 to describe itself and account for it in the statistics. */
445 static void register_heapinfo PP ((void));
446 #ifdef __GNUC__
447 __inline__
448 #endif
449 static void
450 register_heapinfo ()
452 __malloc_size_t block, blocks;
454 block = BLOCK (_heapinfo);
455 blocks = BLOCKIFY (heapsize * sizeof (malloc_info));
457 /* Account for the _heapinfo block itself in the statistics. */
458 _bytes_used += blocks * BLOCKSIZE;
459 ++_chunks_used;
461 /* Describe the heapinfo block itself in the heapinfo. */
462 _heapinfo[block].busy.type = 0;
463 _heapinfo[block].busy.info.size = blocks;
464 /* Leave back-pointers for malloc_find_address. */
465 while (--blocks > 0)
466 _heapinfo[block + blocks].busy.info.size = -blocks;
469 /* Set everything up and remember that we have. */
471 __malloc_initialize ()
473 if (__malloc_initialized)
474 return 0;
476 if (__malloc_initialize_hook)
477 (*__malloc_initialize_hook) ();
479 heapsize = HEAP / BLOCKSIZE;
480 _heapinfo = (malloc_info *) align (heapsize * sizeof (malloc_info));
481 if (_heapinfo == NULL)
482 return 0;
483 memset (_heapinfo, 0, heapsize * sizeof (malloc_info));
484 _heapinfo[0].free.size = 0;
485 _heapinfo[0].free.next = _heapinfo[0].free.prev = 0;
486 _heapindex = 0;
487 _heapbase = (char *) _heapinfo;
488 _heaplimit = BLOCK (_heapbase + heapsize * sizeof (malloc_info));
490 register_heapinfo ();
492 __malloc_initialized = 1;
493 return 1;
496 static int morecore_recursing;
498 /* Get neatly aligned memory, initializing or
499 growing the heap info table as necessary. */
500 static __ptr_t morecore PP ((__malloc_size_t));
501 static __ptr_t
502 morecore (size)
503 __malloc_size_t size;
505 __ptr_t result;
506 malloc_info *newinfo, *oldinfo;
507 __malloc_size_t newsize;
509 if (morecore_recursing)
510 /* Avoid recursion. The caller will know how to handle a null return. */
511 return NULL;
513 result = align (size);
514 if (result == NULL)
515 return NULL;
517 /* Check if we need to grow the info table. */
518 if ((__malloc_size_t) BLOCK ((char *) result + size) > heapsize)
520 /* Calculate the new _heapinfo table size. We do not account for the
521 added blocks in the table itself, as we hope to place them in
522 existing free space, which is already covered by part of the
523 existing table. */
524 newsize = heapsize;
526 newsize *= 2;
527 while ((__malloc_size_t) BLOCK ((char *) result + size) > newsize);
529 /* We must not reuse existing core for the new info table when called
530 from realloc in the case of growing a large block, because the
531 block being grown is momentarily marked as free. In this case
532 _heaplimit is zero so we know not to reuse space for internal
533 allocation. */
534 if (_heaplimit != 0)
536 /* First try to allocate the new info table in core we already
537 have, in the usual way using realloc. If realloc cannot
538 extend it in place or relocate it to existing sufficient core,
539 we will get called again, and the code above will notice the
540 `morecore_recursing' flag and return null. */
541 int save = errno; /* Don't want to clobber errno with ENOMEM. */
542 morecore_recursing = 1;
543 newinfo = (malloc_info *) _realloc_internal
544 (_heapinfo, newsize * sizeof (malloc_info));
545 morecore_recursing = 0;
546 if (newinfo == NULL)
547 errno = save;
548 else
550 /* We found some space in core, and realloc has put the old
551 table's blocks on the free list. Now zero the new part
552 of the table and install the new table location. */
553 memset (&newinfo[heapsize], 0,
554 (newsize - heapsize) * sizeof (malloc_info));
555 _heapinfo = newinfo;
556 heapsize = newsize;
557 goto got_heap;
561 /* Allocate new space for the malloc info table. */
562 while (1)
564 newinfo = (malloc_info *) align (newsize * sizeof (malloc_info));
566 /* Did it fail? */
567 if (newinfo == NULL)
569 (*__morecore) (-size);
570 return NULL;
573 /* Is it big enough to record status for its own space?
574 If so, we win. */
575 if ((__malloc_size_t) BLOCK ((char *) newinfo
576 + newsize * sizeof (malloc_info))
577 < newsize)
578 break;
580 /* Must try again. First give back most of what we just got. */
581 (*__morecore) (- newsize * sizeof (malloc_info));
582 newsize *= 2;
585 /* Copy the old table to the beginning of the new,
586 and zero the rest of the new table. */
587 memcpy (newinfo, _heapinfo, heapsize * sizeof (malloc_info));
588 memset (&newinfo[heapsize], 0,
589 (newsize - heapsize) * sizeof (malloc_info));
590 oldinfo = _heapinfo;
591 _heapinfo = newinfo;
592 heapsize = newsize;
594 register_heapinfo ();
596 /* Reset _heaplimit so _free_internal never decides
597 it can relocate or resize the info table. */
598 _heaplimit = 0;
599 _free_internal (oldinfo);
601 /* The new heap limit includes the new table just allocated. */
602 _heaplimit = BLOCK ((char *) newinfo + heapsize * sizeof (malloc_info));
603 return result;
606 got_heap:
607 _heaplimit = BLOCK ((char *) result + size);
608 return result;
611 /* Allocate memory from the heap. */
612 __ptr_t
613 _malloc_internal (size)
614 __malloc_size_t size;
616 __ptr_t result;
617 __malloc_size_t block, blocks, lastblocks, start;
618 register __malloc_size_t i;
619 struct list *next;
621 /* ANSI C allows `malloc (0)' to either return NULL, or to return a
622 valid address you can realloc and free (though not dereference).
624 It turns out that some extant code (sunrpc, at least Ultrix's version)
625 expects `malloc (0)' to return non-NULL and breaks otherwise.
626 Be compatible. */
628 #if 0
629 if (size == 0)
630 return NULL;
631 #endif
633 if (size < sizeof (struct list))
634 size = sizeof (struct list);
636 #ifdef SUNOS_LOCALTIME_BUG
637 if (size < 16)
638 size = 16;
639 #endif
641 /* Determine the allocation policy based on the request size. */
642 if (size <= BLOCKSIZE / 2)
644 /* Small allocation to receive a fragment of a block.
645 Determine the logarithm to base two of the fragment size. */
646 register __malloc_size_t log = 1;
647 --size;
648 while ((size /= 2) != 0)
649 ++log;
651 /* Look in the fragment lists for a
652 free fragment of the desired size. */
653 next = _fraghead[log].next;
654 if (next != NULL)
656 /* There are free fragments of this size.
657 Pop a fragment out of the fragment list and return it.
658 Update the block's nfree and first counters. */
659 result = (__ptr_t) next;
660 next->prev->next = next->next;
661 if (next->next != NULL)
662 next->next->prev = next->prev;
663 block = BLOCK (result);
664 if (--_heapinfo[block].busy.info.frag.nfree != 0)
665 _heapinfo[block].busy.info.frag.first = (unsigned long int)
666 ((unsigned long int) ((char *) next->next - (char *) NULL)
667 % BLOCKSIZE) >> log;
669 /* Update the statistics. */
670 ++_chunks_used;
671 _bytes_used += 1 << log;
672 --_chunks_free;
673 _bytes_free -= 1 << log;
675 else
677 /* No free fragments of the desired size, so get a new block
678 and break it into fragments, returning the first. */
679 result = malloc (BLOCKSIZE);
680 if (result == NULL)
681 return NULL;
683 /* Link all fragments but the first into the free list. */
684 next = (struct list *) ((char *) result + (1 << log));
685 next->next = NULL;
686 next->prev = &_fraghead[log];
687 _fraghead[log].next = next;
689 for (i = 2; i < (__malloc_size_t) (BLOCKSIZE >> log); ++i)
691 next = (struct list *) ((char *) result + (i << log));
692 next->next = _fraghead[log].next;
693 next->prev = &_fraghead[log];
694 next->prev->next = next;
695 next->next->prev = next;
698 /* Initialize the nfree and first counters for this block. */
699 block = BLOCK (result);
700 _heapinfo[block].busy.type = log;
701 _heapinfo[block].busy.info.frag.nfree = i - 1;
702 _heapinfo[block].busy.info.frag.first = i - 1;
704 _chunks_free += (BLOCKSIZE >> log) - 1;
705 _bytes_free += BLOCKSIZE - (1 << log);
706 _bytes_used -= BLOCKSIZE - (1 << log);
709 else
711 /* Large allocation to receive one or more blocks.
712 Search the free list in a circle starting at the last place visited.
713 If we loop completely around without finding a large enough
714 space we will have to get more memory from the system. */
715 blocks = BLOCKIFY (size);
716 start = block = _heapindex;
717 while (_heapinfo[block].free.size < blocks)
719 block = _heapinfo[block].free.next;
720 if (block == start)
722 /* Need to get more from the system. Get a little extra. */
723 __malloc_size_t wantblocks = blocks + __malloc_extra_blocks;
724 block = _heapinfo[0].free.prev;
725 lastblocks = _heapinfo[block].free.size;
726 /* Check to see if the new core will be contiguous with the
727 final free block; if so we don't need to get as much. */
728 if (_heaplimit != 0 && block + lastblocks == _heaplimit &&
729 /* We can't do this if we will have to make the heap info
730 table bigger to accomodate the new space. */
731 block + wantblocks <= heapsize &&
732 get_contiguous_space ((wantblocks - lastblocks) * BLOCKSIZE,
733 ADDRESS (block + lastblocks)))
735 /* We got it contiguously. Which block we are extending
736 (the `final free block' referred to above) might have
737 changed, if it got combined with a freed info table. */
738 block = _heapinfo[0].free.prev;
739 _heapinfo[block].free.size += (wantblocks - lastblocks);
740 _bytes_free += (wantblocks - lastblocks) * BLOCKSIZE;
741 _heaplimit += wantblocks - lastblocks;
742 continue;
744 result = morecore (wantblocks * BLOCKSIZE);
745 if (result == NULL)
746 return NULL;
747 block = BLOCK (result);
748 /* Put the new block at the end of the free list. */
749 _heapinfo[block].free.size = wantblocks;
750 _heapinfo[block].free.prev = _heapinfo[0].free.prev;
751 _heapinfo[block].free.next = 0;
752 _heapinfo[0].free.prev = block;
753 _heapinfo[_heapinfo[block].free.prev].free.next = block;
754 ++_chunks_free;
755 /* Now loop to use some of that block for this allocation. */
759 /* At this point we have found a suitable free list entry.
760 Figure out how to remove what we need from the list. */
761 result = ADDRESS (block);
762 if (_heapinfo[block].free.size > blocks)
764 /* The block we found has a bit left over,
765 so relink the tail end back into the free list. */
766 _heapinfo[block + blocks].free.size
767 = _heapinfo[block].free.size - blocks;
768 _heapinfo[block + blocks].free.next
769 = _heapinfo[block].free.next;
770 _heapinfo[block + blocks].free.prev
771 = _heapinfo[block].free.prev;
772 _heapinfo[_heapinfo[block].free.prev].free.next
773 = _heapinfo[_heapinfo[block].free.next].free.prev
774 = _heapindex = block + blocks;
776 else
778 /* The block exactly matches our requirements,
779 so just remove it from the list. */
780 _heapinfo[_heapinfo[block].free.next].free.prev
781 = _heapinfo[block].free.prev;
782 _heapinfo[_heapinfo[block].free.prev].free.next
783 = _heapindex = _heapinfo[block].free.next;
784 --_chunks_free;
787 _heapinfo[block].busy.type = 0;
788 _heapinfo[block].busy.info.size = blocks;
789 ++_chunks_used;
790 _bytes_used += blocks * BLOCKSIZE;
791 _bytes_free -= blocks * BLOCKSIZE;
793 /* Mark all the blocks of the object just allocated except for the
794 first with a negative number so you can find the first block by
795 adding that adjustment. */
796 while (--blocks > 0)
797 _heapinfo[block + blocks].busy.info.size = -blocks;
800 return result;
803 __ptr_t
804 malloc (size)
805 __malloc_size_t size;
807 if (!__malloc_initialized && !__malloc_initialize ())
808 return NULL;
810 return (__malloc_hook != NULL ? *__malloc_hook : _malloc_internal) (size);
813 #ifndef _LIBC
815 /* On some ANSI C systems, some libc functions call _malloc, _free
816 and _realloc. Make them use the GNU functions. */
818 __ptr_t
819 _malloc (size)
820 __malloc_size_t size;
822 return malloc (size);
825 void
826 _free (ptr)
827 __ptr_t ptr;
829 free (ptr);
832 __ptr_t
833 _realloc (ptr, size)
834 __ptr_t ptr;
835 __malloc_size_t size;
837 return realloc (ptr, size);
840 #endif
841 /* Free a block of memory allocated by `malloc'.
842 Copyright 1990, 1991, 1992, 1994, 1995 Free Software Foundation, Inc.
843 Written May 1989 by Mike Haertel.
845 This library is free software; you can redistribute it and/or
846 modify it under the terms of the GNU Library General Public License as
847 published by the Free Software Foundation; either version 2 of the
848 License, or (at your option) any later version.
850 This library is distributed in the hope that it will be useful,
851 but WITHOUT ANY WARRANTY; without even the implied warranty of
852 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
853 Library General Public License for more details.
855 You should have received a copy of the GNU Library General Public
856 License along with this library; see the file COPYING.LIB. If
857 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
858 Cambridge, MA 02139, USA.
860 The author may be reached (Email) at the address mike@ai.mit.edu,
861 or (US mail) as Mike Haertel c/o Free Software Foundation. */
863 #ifndef _MALLOC_INTERNAL
864 #define _MALLOC_INTERNAL
865 #include <malloc.h>
866 #endif
869 /* Cope with systems lacking `memmove'. */
870 #ifndef memmove
871 #if (defined (MEMMOVE_MISSING) || \
872 !defined(_LIBC) && !defined(STDC_HEADERS) && !defined(USG))
873 #ifdef emacs
874 #undef __malloc_safe_bcopy
875 #define __malloc_safe_bcopy safe_bcopy
876 #endif
877 /* This function is defined in realloc.c. */
878 extern void __malloc_safe_bcopy PP ((__ptr_t, __ptr_t, __malloc_size_t));
879 #define memmove(to, from, size) __malloc_safe_bcopy ((from), (to), (size))
880 #endif
881 #endif
884 /* Debugging hook for free. */
885 void (*__free_hook) PP ((__ptr_t __ptr));
887 /* List of blocks allocated by memalign. */
888 struct alignlist *_aligned_blocks = NULL;
890 /* Return memory to the heap.
891 Like `free' but don't call a __free_hook if there is one. */
892 void
893 _free_internal (ptr)
894 __ptr_t ptr;
896 int type;
897 __malloc_size_t block, blocks;
898 register __malloc_size_t i;
899 struct list *prev, *next;
900 __ptr_t curbrk;
901 const __malloc_size_t lesscore_threshold
902 /* Threshold of free space at which we will return some to the system. */
903 = FINAL_FREE_BLOCKS + 2 * __malloc_extra_blocks;
905 register struct alignlist *l;
907 if (ptr == NULL)
908 return;
910 for (l = _aligned_blocks; l != NULL; l = l->next)
911 if (l->aligned == ptr)
913 l->aligned = NULL; /* Mark the slot in the list as free. */
914 ptr = l->exact;
915 break;
918 block = BLOCK (ptr);
920 type = _heapinfo[block].busy.type;
921 switch (type)
923 case 0:
924 /* Get as many statistics as early as we can. */
925 --_chunks_used;
926 _bytes_used -= _heapinfo[block].busy.info.size * BLOCKSIZE;
927 _bytes_free += _heapinfo[block].busy.info.size * BLOCKSIZE;
929 /* Find the free cluster previous to this one in the free list.
930 Start searching at the last block referenced; this may benefit
931 programs with locality of allocation. */
932 i = _heapindex;
933 if (i > block)
934 while (i > block)
935 i = _heapinfo[i].free.prev;
936 else
939 i = _heapinfo[i].free.next;
940 while (i > 0 && i < block);
941 i = _heapinfo[i].free.prev;
944 /* Determine how to link this block into the free list. */
945 if (block == i + _heapinfo[i].free.size)
947 /* Coalesce this block with its predecessor. */
948 _heapinfo[i].free.size += _heapinfo[block].busy.info.size;
949 block = i;
951 else
953 /* Really link this block back into the free list. */
954 _heapinfo[block].free.size = _heapinfo[block].busy.info.size;
955 _heapinfo[block].free.next = _heapinfo[i].free.next;
956 _heapinfo[block].free.prev = i;
957 _heapinfo[i].free.next = block;
958 _heapinfo[_heapinfo[block].free.next].free.prev = block;
959 ++_chunks_free;
962 /* Now that the block is linked in, see if we can coalesce it
963 with its successor (by deleting its successor from the list
964 and adding in its size). */
965 if (block + _heapinfo[block].free.size == _heapinfo[block].free.next)
967 _heapinfo[block].free.size
968 += _heapinfo[_heapinfo[block].free.next].free.size;
969 _heapinfo[block].free.next
970 = _heapinfo[_heapinfo[block].free.next].free.next;
971 _heapinfo[_heapinfo[block].free.next].free.prev = block;
972 --_chunks_free;
975 /* How many trailing free blocks are there now? */
976 blocks = _heapinfo[block].free.size;
978 /* Where is the current end of accessible core? */
979 curbrk = (*__morecore) (0);
981 if (_heaplimit != 0 && curbrk == ADDRESS (_heaplimit))
983 /* The end of the malloc heap is at the end of accessible core.
984 It's possible that moving _heapinfo will allow us to
985 return some space to the system. */
987 __malloc_size_t info_block = BLOCK (_heapinfo);
988 __malloc_size_t info_blocks = _heapinfo[info_block].busy.info.size;
989 __malloc_size_t prev_block = _heapinfo[block].free.prev;
990 __malloc_size_t prev_blocks = _heapinfo[prev_block].free.size;
991 __malloc_size_t next_block = _heapinfo[block].free.next;
992 __malloc_size_t next_blocks = _heapinfo[next_block].free.size;
994 if (/* Win if this block being freed is last in core, the info table
995 is just before it, the previous free block is just before the
996 info table, and the two free blocks together form a useful
997 amount to return to the system. */
998 (block + blocks == _heaplimit &&
999 info_block + info_blocks == block &&
1000 prev_block != 0 && prev_block + prev_blocks == info_block &&
1001 blocks + prev_blocks >= lesscore_threshold) ||
1002 /* Nope, not the case. We can also win if this block being
1003 freed is just before the info table, and the table extends
1004 to the end of core or is followed only by a free block,
1005 and the total free space is worth returning to the system. */
1006 (block + blocks == info_block &&
1007 ((info_block + info_blocks == _heaplimit &&
1008 blocks >= lesscore_threshold) ||
1009 (info_block + info_blocks == next_block &&
1010 next_block + next_blocks == _heaplimit &&
1011 blocks + next_blocks >= lesscore_threshold)))
1014 malloc_info *newinfo;
1015 __malloc_size_t oldlimit = _heaplimit;
1017 /* Free the old info table, clearing _heaplimit to avoid
1018 recursion into this code. We don't want to return the
1019 table's blocks to the system before we have copied them to
1020 the new location. */
1021 _heaplimit = 0;
1022 _free_internal (_heapinfo);
1023 _heaplimit = oldlimit;
1025 /* Tell malloc to search from the beginning of the heap for
1026 free blocks, so it doesn't reuse the ones just freed. */
1027 _heapindex = 0;
1029 /* Allocate new space for the info table and move its data. */
1030 newinfo = (malloc_info *) _malloc_internal (info_blocks
1031 * BLOCKSIZE);
1032 memmove (newinfo, _heapinfo, info_blocks * BLOCKSIZE);
1033 _heapinfo = newinfo;
1035 /* We should now have coalesced the free block with the
1036 blocks freed from the old info table. Examine the entire
1037 trailing free block to decide below whether to return some
1038 to the system. */
1039 block = _heapinfo[0].free.prev;
1040 blocks = _heapinfo[block].free.size;
1043 /* Now see if we can return stuff to the system. */
1044 if (block + blocks == _heaplimit && blocks >= lesscore_threshold)
1046 register __malloc_size_t bytes = blocks * BLOCKSIZE;
1047 _heaplimit -= blocks;
1048 (*__morecore) (-bytes);
1049 _heapinfo[_heapinfo[block].free.prev].free.next
1050 = _heapinfo[block].free.next;
1051 _heapinfo[_heapinfo[block].free.next].free.prev
1052 = _heapinfo[block].free.prev;
1053 block = _heapinfo[block].free.prev;
1054 --_chunks_free;
1055 _bytes_free -= bytes;
1059 /* Set the next search to begin at this block. */
1060 _heapindex = block;
1061 break;
1063 default:
1064 /* Do some of the statistics. */
1065 --_chunks_used;
1066 _bytes_used -= 1 << type;
1067 ++_chunks_free;
1068 _bytes_free += 1 << type;
1070 /* Get the address of the first free fragment in this block. */
1071 prev = (struct list *) ((char *) ADDRESS (block) +
1072 (_heapinfo[block].busy.info.frag.first << type));
1074 if (_heapinfo[block].busy.info.frag.nfree == (BLOCKSIZE >> type) - 1)
1076 /* If all fragments of this block are free, remove them
1077 from the fragment list and free the whole block. */
1078 next = prev;
1079 for (i = 1; i < (__malloc_size_t) (BLOCKSIZE >> type); ++i)
1080 next = next->next;
1081 prev->prev->next = next;
1082 if (next != NULL)
1083 next->prev = prev->prev;
1084 _heapinfo[block].busy.type = 0;
1085 _heapinfo[block].busy.info.size = 1;
1087 /* Keep the statistics accurate. */
1088 ++_chunks_used;
1089 _bytes_used += BLOCKSIZE;
1090 _chunks_free -= BLOCKSIZE >> type;
1091 _bytes_free -= BLOCKSIZE;
1093 free (ADDRESS (block));
1095 else if (_heapinfo[block].busy.info.frag.nfree != 0)
1097 /* If some fragments of this block are free, link this
1098 fragment into the fragment list after the first free
1099 fragment of this block. */
1100 next = (struct list *) ptr;
1101 next->next = prev->next;
1102 next->prev = prev;
1103 prev->next = next;
1104 if (next->next != NULL)
1105 next->next->prev = next;
1106 ++_heapinfo[block].busy.info.frag.nfree;
1108 else
1110 /* No fragments of this block are free, so link this
1111 fragment into the fragment list and announce that
1112 it is the first free fragment of this block. */
1113 prev = (struct list *) ptr;
1114 _heapinfo[block].busy.info.frag.nfree = 1;
1115 _heapinfo[block].busy.info.frag.first = (unsigned long int)
1116 ((unsigned long int) ((char *) ptr - (char *) NULL)
1117 % BLOCKSIZE >> type);
1118 prev->next = _fraghead[type].next;
1119 prev->prev = &_fraghead[type];
1120 prev->prev->next = prev;
1121 if (prev->next != NULL)
1122 prev->next->prev = prev;
1124 break;
1128 /* Return memory to the heap. */
1129 void
1130 free (ptr)
1131 __ptr_t ptr;
1133 if (__free_hook != NULL)
1134 (*__free_hook) (ptr);
1135 else
1136 _free_internal (ptr);
1139 /* Define the `cfree' alias for `free'. */
1140 #ifdef weak_alias
1141 weak_alias (free, cfree)
1142 #else
1143 void
1144 cfree (ptr)
1145 __ptr_t ptr;
1147 free (ptr);
1149 #endif
1150 /* Change the size of a block allocated by `malloc'.
1151 Copyright 1990, 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
1152 Written May 1989 by Mike Haertel.
1154 This library is free software; you can redistribute it and/or
1155 modify it under the terms of the GNU Library General Public License as
1156 published by the Free Software Foundation; either version 2 of the
1157 License, or (at your option) any later version.
1159 This library is distributed in the hope that it will be useful,
1160 but WITHOUT ANY WARRANTY; without even the implied warranty of
1161 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
1162 Library General Public License for more details.
1164 You should have received a copy of the GNU Library General Public
1165 License along with this library; see the file COPYING.LIB. If
1166 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
1167 Cambridge, MA 02139, USA.
1169 The author may be reached (Email) at the address mike@ai.mit.edu,
1170 or (US mail) as Mike Haertel c/o Free Software Foundation. */
1172 #ifndef _MALLOC_INTERNAL
1173 #define _MALLOC_INTERNAL
1174 #include <malloc.h>
1175 #endif
1179 /* Cope with systems lacking `memmove'. */
1180 #if (defined (MEMMOVE_MISSING) || \
1181 !defined(_LIBC) && !defined(STDC_HEADERS) && !defined(USG))
1183 #ifdef emacs
1184 #undef __malloc_safe_bcopy
1185 #define __malloc_safe_bcopy safe_bcopy
1186 #else
1188 /* Snarfed directly from Emacs src/dispnew.c:
1189 XXX Should use system bcopy if it handles overlap. */
1191 /* Like bcopy except never gets confused by overlap. */
1193 void
1194 __malloc_safe_bcopy (afrom, ato, size)
1195 __ptr_t afrom;
1196 __ptr_t ato;
1197 __malloc_size_t size;
1199 char *from = afrom, *to = ato;
1201 if (size <= 0 || from == to)
1202 return;
1204 /* If the source and destination don't overlap, then bcopy can
1205 handle it. If they do overlap, but the destination is lower in
1206 memory than the source, we'll assume bcopy can handle that. */
1207 if (to < from || from + size <= to)
1208 bcopy (from, to, size);
1210 /* Otherwise, we'll copy from the end. */
1211 else
1213 register char *endf = from + size;
1214 register char *endt = to + size;
1216 /* If TO - FROM is large, then we should break the copy into
1217 nonoverlapping chunks of TO - FROM bytes each. However, if
1218 TO - FROM is small, then the bcopy function call overhead
1219 makes this not worth it. The crossover point could be about
1220 anywhere. Since I don't think the obvious copy loop is too
1221 bad, I'm trying to err in its favor. */
1222 if (to - from < 64)
1225 *--endt = *--endf;
1226 while (endf != from);
1228 else
1230 for (;;)
1232 endt -= (to - from);
1233 endf -= (to - from);
1235 if (endt < to)
1236 break;
1238 bcopy (endf, endt, to - from);
1241 /* If SIZE wasn't a multiple of TO - FROM, there will be a
1242 little left over. The amount left over is
1243 (endt + (to - from)) - to, which is endt - from. */
1244 bcopy (from, to, endt - from);
1248 #endif /* emacs */
1250 #ifndef memmove
1251 extern void __malloc_safe_bcopy PP ((__ptr_t, __ptr_t, __malloc_size_t));
1252 #define memmove(to, from, size) __malloc_safe_bcopy ((from), (to), (size))
1253 #endif
1255 #endif
1258 #define min(A, B) ((A) < (B) ? (A) : (B))
1260 /* Debugging hook for realloc. */
1261 __ptr_t (*__realloc_hook) PP ((__ptr_t __ptr, __malloc_size_t __size));
1263 /* Resize the given region to the new size, returning a pointer
1264 to the (possibly moved) region. This is optimized for speed;
1265 some benchmarks seem to indicate that greater compactness is
1266 achieved by unconditionally allocating and copying to a
1267 new region. This module has incestuous knowledge of the
1268 internals of both free and malloc. */
1269 __ptr_t
1270 _realloc_internal (ptr, size)
1271 __ptr_t ptr;
1272 __malloc_size_t size;
1274 __ptr_t result;
1275 int type;
1276 __malloc_size_t block, blocks, oldlimit;
1278 if (size == 0)
1280 _free_internal (ptr);
1281 return _malloc_internal (0);
1283 else if (ptr == NULL)
1284 return _malloc_internal (size);
1286 block = BLOCK (ptr);
1288 type = _heapinfo[block].busy.type;
1289 switch (type)
1291 case 0:
1292 /* Maybe reallocate a large block to a small fragment. */
1293 if (size <= BLOCKSIZE / 2)
1295 result = _malloc_internal (size);
1296 if (result != NULL)
1298 memcpy (result, ptr, size);
1299 _free_internal (ptr);
1300 return result;
1304 /* The new size is a large allocation as well;
1305 see if we can hold it in place. */
1306 blocks = BLOCKIFY (size);
1307 if (blocks < _heapinfo[block].busy.info.size)
1309 /* The new size is smaller; return
1310 excess memory to the free list. */
1311 _heapinfo[block + blocks].busy.type = 0;
1312 _heapinfo[block + blocks].busy.info.size
1313 = _heapinfo[block].busy.info.size - blocks;
1314 _heapinfo[block].busy.info.size = blocks;
1315 /* We have just created a new chunk by splitting a chunk in two.
1316 Now we will free this chunk; increment the statistics counter
1317 so it doesn't become wrong when _free_internal decrements it. */
1318 ++_chunks_used;
1319 _free_internal (ADDRESS (block + blocks));
1320 result = ptr;
1322 else if (blocks == _heapinfo[block].busy.info.size)
1323 /* No size change necessary. */
1324 result = ptr;
1325 else
1327 /* Won't fit, so allocate a new region that will.
1328 Free the old region first in case there is sufficient
1329 adjacent free space to grow without moving. */
1330 blocks = _heapinfo[block].busy.info.size;
1331 /* Prevent free from actually returning memory to the system. */
1332 oldlimit = _heaplimit;
1333 _heaplimit = 0;
1334 _free_internal (ptr);
1335 result = _malloc_internal (size);
1336 if (_heaplimit == 0)
1337 _heaplimit = oldlimit;
1338 if (result == NULL)
1340 /* Now we're really in trouble. We have to unfree
1341 the thing we just freed. Unfortunately it might
1342 have been coalesced with its neighbors. */
1343 if (_heapindex == block)
1344 (void) _malloc_internal (blocks * BLOCKSIZE);
1345 else
1347 __ptr_t previous
1348 = _malloc_internal ((block - _heapindex) * BLOCKSIZE);
1349 (void) _malloc_internal (blocks * BLOCKSIZE);
1350 _free_internal (previous);
1352 return NULL;
1354 if (ptr != result)
1355 memmove (result, ptr, blocks * BLOCKSIZE);
1357 break;
1359 default:
1360 /* Old size is a fragment; type is logarithm
1361 to base two of the fragment size. */
1362 if (size > (__malloc_size_t) (1 << (type - 1)) &&
1363 size <= (__malloc_size_t) (1 << type))
1364 /* The new size is the same kind of fragment. */
1365 result = ptr;
1366 else
1368 /* The new size is different; allocate a new space,
1369 and copy the lesser of the new size and the old. */
1370 result = _malloc_internal (size);
1371 if (result == NULL)
1372 return NULL;
1373 memcpy (result, ptr, min (size, (__malloc_size_t) 1 << type));
1374 _free_internal (ptr);
1376 break;
1379 return result;
1382 __ptr_t
1383 realloc (ptr, size)
1384 __ptr_t ptr;
1385 __malloc_size_t size;
1387 if (!__malloc_initialized && !__malloc_initialize ())
1388 return NULL;
1390 return (__realloc_hook != NULL ? *__realloc_hook : _realloc_internal)
1391 (ptr, size);
1393 /* Copyright (C) 1991, 1992, 1994 Free Software Foundation, Inc.
1395 This library is free software; you can redistribute it and/or
1396 modify it under the terms of the GNU Library General Public License as
1397 published by the Free Software Foundation; either version 2 of the
1398 License, or (at your option) any later version.
1400 This library is distributed in the hope that it will be useful,
1401 but WITHOUT ANY WARRANTY; without even the implied warranty of
1402 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
1403 Library General Public License for more details.
1405 You should have received a copy of the GNU Library General Public
1406 License along with this library; see the file COPYING.LIB. If
1407 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
1408 Cambridge, MA 02139, USA.
1410 The author may be reached (Email) at the address mike@ai.mit.edu,
1411 or (US mail) as Mike Haertel c/o Free Software Foundation. */
1413 #ifndef _MALLOC_INTERNAL
1414 #define _MALLOC_INTERNAL
1415 #include <malloc.h>
1416 #endif
1418 /* Allocate an array of NMEMB elements each SIZE bytes long.
1419 The entire array is initialized to zeros. */
1420 __ptr_t
1421 calloc (nmemb, size)
1422 register __malloc_size_t nmemb;
1423 register __malloc_size_t size;
1425 register __ptr_t result = malloc (nmemb * size);
1427 if (result != NULL)
1428 (void) memset (result, 0, nmemb * size);
1430 return result;
1432 /* Copyright (C) 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
1433 This file is part of the GNU C Library.
1435 The GNU C Library is free software; you can redistribute it and/or modify
1436 it under the terms of the GNU General Public License as published by
1437 the Free Software Foundation; either version 2, or (at your option)
1438 any later version.
1440 The GNU C Library is distributed in the hope that it will be useful,
1441 but WITHOUT ANY WARRANTY; without even the implied warranty of
1442 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1443 GNU General Public License for more details.
1445 You should have received a copy of the GNU General Public License
1446 along with the GNU C Library; see the file COPYING. If not, write to
1447 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
1449 #ifndef _MALLOC_INTERNAL
1450 #define _MALLOC_INTERNAL
1451 #include <malloc.h>
1452 #endif
1454 #ifndef __GNU_LIBRARY__
1455 #define __sbrk sbrk
1456 #endif
1458 #ifdef __GNU_LIBRARY__
1459 /* It is best not to declare this and cast its result on foreign operating
1460 systems with potentially hostile include files. */
1462 #include <stddef.h>
1463 extern __ptr_t __sbrk PP ((ptrdiff_t increment));
1464 #endif
1466 #ifndef NULL
1467 #define NULL 0
1468 #endif
1470 /* Allocate INCREMENT more bytes of data space,
1471 and return the start of data space, or NULL on errors.
1472 If INCREMENT is negative, shrink data space. */
1473 __ptr_t
1474 __default_morecore (increment)
1475 __malloc_ptrdiff_t increment;
1477 __ptr_t result = (__ptr_t) __sbrk (increment);
1478 if (result == (__ptr_t) -1)
1479 return NULL;
1480 return result;
1482 /* Copyright (C) 1991, 92, 93, 94, 95, 96 Free Software Foundation, Inc.
1484 This library is free software; you can redistribute it and/or
1485 modify it under the terms of the GNU Library General Public License as
1486 published by the Free Software Foundation; either version 2 of the
1487 License, or (at your option) any later version.
1489 This library is distributed in the hope that it will be useful,
1490 but WITHOUT ANY WARRANTY; without even the implied warranty of
1491 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
1492 Library General Public License for more details.
1494 You should have received a copy of the GNU Library General Public
1495 License along with this library; see the file COPYING.LIB. If
1496 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
1497 Cambridge, MA 02139, USA. */
1499 #ifndef _MALLOC_INTERNAL
1500 #define _MALLOC_INTERNAL
1501 #include <malloc.h>
1502 #endif
1504 #if __DJGPP__ - 0 == 1
1506 /* There is some problem with memalign in DJGPP v1 and we are supposed
1507 to omit it. Noone told me why, they just told me to do it. */
1509 #else
1511 __ptr_t (*__memalign_hook) PP ((size_t __size, size_t __alignment));
1513 __ptr_t
1514 memalign (alignment, size)
1515 __malloc_size_t alignment;
1516 __malloc_size_t size;
1518 __ptr_t result;
1519 unsigned long int adj, lastadj;
1521 if (__memalign_hook)
1522 return (*__memalign_hook) (alignment, size);
1524 /* Allocate a block with enough extra space to pad the block with up to
1525 (ALIGNMENT - 1) bytes if necessary. */
1526 result = malloc (size + alignment - 1);
1527 if (result == NULL)
1528 return NULL;
1530 /* Figure out how much we will need to pad this particular block
1531 to achieve the required alignment. */
1532 adj = (unsigned long int) ((char *) result - (char *) NULL) % alignment;
1536 /* Reallocate the block with only as much excess as it needs. */
1537 free (result);
1538 result = malloc (adj + size);
1539 if (result == NULL) /* Impossible unless interrupted. */
1540 return NULL;
1542 lastadj = adj;
1543 adj = (unsigned long int) ((char *) result - (char *) NULL) % alignment;
1544 /* It's conceivable we might have been so unlucky as to get a
1545 different block with weaker alignment. If so, this block is too
1546 short to contain SIZE after alignment correction. So we must
1547 try again and get another block, slightly larger. */
1548 } while (adj > lastadj);
1550 if (adj != 0)
1552 /* Record this block in the list of aligned blocks, so that `free'
1553 can identify the pointer it is passed, which will be in the middle
1554 of an allocated block. */
1556 struct alignlist *l;
1557 for (l = _aligned_blocks; l != NULL; l = l->next)
1558 if (l->aligned == NULL)
1559 /* This slot is free. Use it. */
1560 break;
1561 if (l == NULL)
1563 l = (struct alignlist *) malloc (sizeof (struct alignlist));
1564 if (l == NULL)
1566 free (result);
1567 return NULL;
1569 l->next = _aligned_blocks;
1570 _aligned_blocks = l;
1572 l->exact = result;
1573 result = l->aligned = (char *) result + alignment - adj;
1576 return result;
1579 #endif /* Not DJGPP v1 */
1580 /* Allocate memory on a page boundary.
1581 Copyright (C) 1991, 92, 93, 94, 96 Free Software Foundation, Inc.
1583 This library is free software; you can redistribute it and/or
1584 modify it under the terms of the GNU Library General Public License as
1585 published by the Free Software Foundation; either version 2 of the
1586 License, or (at your option) any later version.
1588 This library is distributed in the hope that it will be useful,
1589 but WITHOUT ANY WARRANTY; without even the implied warranty of
1590 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
1591 Library General Public License for more details.
1593 You should have received a copy of the GNU Library General Public
1594 License along with this library; see the file COPYING.LIB. If
1595 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
1596 Cambridge, MA 02139, USA.
1598 The author may be reached (Email) at the address mike@ai.mit.edu,
1599 or (US mail) as Mike Haertel c/o Free Software Foundation. */
1601 #if defined (_MALLOC_INTERNAL) && defined (GMALLOC_INHIBIT_VALLOC)
1603 /* Emacs defines GMALLOC_INHIBIT_VALLOC to avoid this definition
1604 on MSDOS, where it conflicts with a system header file. */
1606 #define ELIDE_VALLOC
1608 #endif
1610 #ifndef ELIDE_VALLOC
1612 #if defined (__GNU_LIBRARY__) || defined (_LIBC)
1613 #include <stddef.h>
1614 #include <sys/cdefs.h>
1615 #if defined (__GLIBC__) && __GLIBC__ >= 2
1616 /* __getpagesize is already declared in <unistd.h> with return type int */
1617 #else
1618 extern size_t __getpagesize PP ((void));
1619 #endif
1620 #else
1621 #include "getpagesize.h"
1622 #define __getpagesize() getpagesize()
1623 #endif
1625 #ifndef _MALLOC_INTERNAL
1626 #define _MALLOC_INTERNAL
1627 #include <malloc.h>
1628 #endif
1630 static __malloc_size_t pagesize;
1632 __ptr_t
1633 valloc (size)
1634 __malloc_size_t size;
1636 if (pagesize == 0)
1637 pagesize = __getpagesize ();
1639 return memalign (pagesize, size);
1642 #endif /* Not ELIDE_VALLOC. */