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-rw-r--r--lib/malloclib/malloc.c324
1 files changed, 0 insertions, 324 deletions
diff --git a/lib/malloclib/malloc.c b/lib/malloclib/malloc.c
deleted file mode 100644
index 1d9bc03..0000000
--- a/lib/malloclib/malloc.c
+++ /dev/null
@@ -1,324 +0,0 @@
-/* Memory allocator `malloc'.
- Copyright 1990, 1991, 1992, 1993 Free Software Foundation
- Written May 1989 by Mike Haertel.
-
-This library is free software; you can redistribute it and/or
-modify it under the terms of the GNU Library General Public License as
-published by the Free Software Foundation; either version 2 of the
-License, or (at your option) any later version.
-
-This library is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-Library General Public License for more details.
-
-You should have received a copy of the GNU Library General Public
-License along with this library; see the file COPYING.LIB. If
-not, write to the Free Software Foundation, Inc., 675 Mass Ave,
-Cambridge, MA 02139, USA.
-
- The author may be reached (Email) at the address mike@ai.mit.edu,
- or (US mail) as Mike Haertel c/o Free Software Foundation. */
-
-#ifndef _MALLOC_INTERNAL
-#define _MALLOC_INTERNAL
-#include <malloc.h>
-#endif
-
-/* How to really get more memory. */
-__ptr_t (*__morecore) __P ((ptrdiff_t __size)) = __default_morecore;
-
-/* Debugging hook for `malloc'. */
-__ptr_t (*__malloc_hook) __P ((size_t __size));
-
-/* Pointer to the base of the first block. */
-char *_heapbase;
-
-/* Block information table. Allocated with align/__free (not malloc/free). */
-malloc_info *_heapinfo;
-
-/* Number of info entries. */
-static size_t heapsize;
-
-/* Search index in the info table. */
-size_t _heapindex;
-
-/* Limit of valid info table indices. */
-size_t _heaplimit;
-
-/* Count of large blocks allocated for each fragment size. */
-int _fragblocks[BLOCKLOG];
-
-/* Free lists for each fragment size. */
-struct list _fraghead[BLOCKLOG];
-
-/* Instrumentation. */
-size_t _chunks_used;
-size_t _bytes_used;
-size_t _chunks_free;
-size_t _bytes_free;
-
-/* Are you experienced? */
-int __malloc_initialized;
-
-void (*__after_morecore_hook) __P ((void));
-
-/* Aligned allocation. */
-static __ptr_t align __P ((size_t));
-static __ptr_t
-align (size)
- size_t size;
-{
- __ptr_t result;
- unsigned long int adj;
-
- result = (*__morecore) (size);
- adj = (unsigned long int) ((unsigned long int) ((char *) result -
- (char *) NULL)) % BLOCKSIZE;
- if (adj != 0)
- {
- adj = BLOCKSIZE - adj;
- (void) (*__morecore) (adj);
- result = (char *) result + adj;
- }
-
- if (__after_morecore_hook)
- (*__after_morecore_hook) ();
-
- return result;
-}
-
-/* Set everything up and remember that we have. */
-static int initialize __P ((void));
-static int
-initialize ()
-{
- heapsize = HEAP / BLOCKSIZE;
- _heapinfo = (malloc_info *) align (heapsize * sizeof (malloc_info));
-
- _bytes_used = heapsize * sizeof (malloc_info);
- _chunks_used++;
-
- if (_heapinfo == NULL)
- return 0;
- memset (_heapinfo, 0, heapsize * sizeof (malloc_info));
- _heapinfo[0].free.size = 0;
- _heapinfo[0].free.next = _heapinfo[0].free.prev = 0;
- _heapindex = 0;
- _heapbase = (char *) _heapinfo;
- __malloc_initialized = 1;
- return 1;
-}
-
-/* Get neatly aligned memory, initializing or
- growing the heap info table as necessary. */
-static __ptr_t morecore __P ((size_t));
-static __ptr_t
-morecore (size)
- size_t size;
-{
- __ptr_t result;
- malloc_info *newinfo, *oldinfo;
- size_t newsize;
-
- result = align (size);
- if (result == NULL)
- return NULL;
-
- /* Check if we need to grow the info table. */
- if ((size_t) BLOCK ((char *) result + size) > heapsize)
- {
- newsize = heapsize;
- while ((size_t) BLOCK ((char *) result + size) > newsize)
- newsize *= 2;
- newinfo = (malloc_info *) align (newsize * sizeof (malloc_info));
- if (newinfo == NULL)
- {
- (*__morecore) (-size);
- return NULL;
- }
-
- _bytes_used += newsize * sizeof (malloc_info);
- _chunks_used++;
-
- memset (newinfo, 0, newsize * sizeof (malloc_info));
- memcpy (newinfo, _heapinfo, heapsize * sizeof (malloc_info));
- oldinfo = _heapinfo;
- newinfo[BLOCK (oldinfo)].busy.type = 0;
- newinfo[BLOCK (oldinfo)].busy.info.size
- = BLOCKIFY (heapsize * sizeof (malloc_info));
- _heapinfo = newinfo;
-
- heapsize = newsize;
- }
-
- _heaplimit = BLOCK ((char *) result + size);
- return result;
-}
-
-/* Allocate memory from the heap. */
-__ptr_t
-malloc (size)
- size_t size;
-{
- __ptr_t result;
- size_t block, blocks, lastblocks, start;
- register size_t i;
- struct list *next;
-
- if (size == 0)
- return NULL;
-
- if (__malloc_hook != NULL)
- return (*__malloc_hook) (size);
-
- if (!__malloc_initialized)
- if (!initialize ())
- return NULL;
-
- if (size < sizeof (struct list))
- size = sizeof (struct list);
-
- /* Determine the allocation policy based on the request size. */
- if (size <= BLOCKSIZE / 2)
- {
- /* Small allocation to receive a fragment of a block.
- Determine the logarithm to base two of the fragment size. */
- register size_t log = 1;
- --size;
- while ((size /= 2) != 0)
- ++log;
-
- /* Look in the fragment lists for a
- free fragment of the desired size. */
- next = _fraghead[log].next;
- if (next != NULL)
- {
- /* There are free fragments of this size.
- Pop a fragment out of the fragment list and return it.
- Update the block's nfree and first counters. */
- result = (__ptr_t) next;
- next->prev->next = next->next;
- if (next->next != NULL)
- next->next->prev = next->prev;
- block = BLOCK (result);
- if (--_heapinfo[block].busy.info.frag.nfree != 0)
- _heapinfo[block].busy.info.frag.first = (unsigned long int)
- ((unsigned long int) ((char *) next->next - (char *) NULL)
- % BLOCKSIZE) >> log;
-
- /* Update the statistics. */
- ++_chunks_used;
- _bytes_used += 1 << log;
- --_chunks_free;
- _bytes_free -= 1 << log;
- }
- else
- {
- /* No free fragments of the desired size, so get a new block
- and break it into fragments, returning the first. */
- result = malloc (BLOCKSIZE);
- if (result == NULL)
- return NULL;
- ++_fragblocks[log];
-
- /* Link all fragments but the first into the free list. */
- for (i = 1; i < (size_t) (BLOCKSIZE >> log); ++i)
- {
- next = (struct list *) ((char *) result + (i << log));
- next->next = _fraghead[log].next;
- next->prev = &_fraghead[log];
- next->prev->next = next;
- if (next->next != NULL)
- next->next->prev = next;
- }
-
- /* Initialize the nfree and first counters for this block. */
- block = BLOCK (result);
- _heapinfo[block].busy.type = log;
- _heapinfo[block].busy.info.frag.nfree = i - 1;
- _heapinfo[block].busy.info.frag.first = i - 1;
-
- _chunks_free += (BLOCKSIZE >> log) - 1;
- _bytes_free += BLOCKSIZE - (1 << log);
- _bytes_used -= BLOCKSIZE - (1 << log);
- }
- }
- else
- {
- /* Large allocation to receive one or more blocks.
- Search the free list in a circle starting at the last place visited.
- If we loop completely around without finding a large enough
- space we will have to get more memory from the system. */
- blocks = BLOCKIFY (size);
- start = block = _heapindex;
- while (_heapinfo[block].free.size < blocks)
- {
- block = _heapinfo[block].free.next;
- if (block == start)
- {
- /* Need to get more from the system. Check to see if
- the new core will be contiguous with the final free
- block; if so we don't need to get as much. */
- block = _heapinfo[0].free.prev;
- lastblocks = _heapinfo[block].free.size;
- if (_heaplimit != 0 && block + lastblocks == _heaplimit &&
- (*__morecore) (0) == ADDRESS (block + lastblocks) &&
- (morecore ((blocks - lastblocks) * BLOCKSIZE)) != NULL)
- {
- /* Note that morecore() can change the location of
- the final block if it moves the info table and the
- old one gets coalesced into the final block. */
- block = _heapinfo[0].free.prev;
- _heapinfo[block].free.size += blocks - lastblocks;
- continue;
- }
- result = morecore (blocks * BLOCKSIZE);
- if (result == NULL)
- return NULL;
- block = BLOCK (result);
- _heapinfo[block].busy.type = 0;
- _heapinfo[block].busy.info.size = blocks;
- ++_chunks_used;
- _bytes_used += blocks * BLOCKSIZE;
- return result;
- }
- }
-
- /* At this point we have found a suitable free list entry.
- Figure out how to remove what we need from the list. */
- result = ADDRESS (block);
- if (_heapinfo[block].free.size > blocks)
- {
- /* The block we found has a bit left over,
- so relink the tail end back into the free list. */
- _heapinfo[block + blocks].free.size
- = _heapinfo[block].free.size - blocks;
- _heapinfo[block + blocks].free.next
- = _heapinfo[block].free.next;
- _heapinfo[block + blocks].free.prev
- = _heapinfo[block].free.prev;
- _heapinfo[_heapinfo[block].free.prev].free.next
- = _heapinfo[_heapinfo[block].free.next].free.prev
- = _heapindex = block + blocks;
- }
- else
- {
- /* The block exactly matches our requirements,
- so just remove it from the list. */
- _heapinfo[_heapinfo[block].free.next].free.prev
- = _heapinfo[block].free.prev;
- _heapinfo[_heapinfo[block].free.prev].free.next
- = _heapindex = _heapinfo[block].free.next;
- --_chunks_free;
- }
-
- _heapinfo[block].busy.type = 0;
- _heapinfo[block].busy.info.size = blocks;
- ++_chunks_used;
- _bytes_used += blocks * BLOCKSIZE;
- _bytes_free -= blocks * BLOCKSIZE;
- }
-
- return result;
-}
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