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-rw-r--r--gnu/lib/libmalloc/realloc.c146
1 files changed, 0 insertions, 146 deletions
diff --git a/gnu/lib/libmalloc/realloc.c b/gnu/lib/libmalloc/realloc.c
deleted file mode 100644
index 2d31766..0000000
--- a/gnu/lib/libmalloc/realloc.c
+++ /dev/null
@@ -1,146 +0,0 @@
-/* Change the size of a block allocated by `malloc'.
- Copyright 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
- 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
-
-#define min(A, B) ((A) < (B) ? (A) : (B))
-
-/* Debugging hook for realloc. */
-__ptr_t (*__realloc_hook) __P ((__ptr_t __ptr, size_t __size));
-
-/* Resize the given region to the new size, returning a pointer
- to the (possibly moved) region. This is optimized for speed;
- some benchmarks seem to indicate that greater compactness is
- achieved by unconditionally allocating and copying to a
- new region. This module has incestuous knowledge of the
- internals of both free and malloc. */
-__ptr_t
-realloc (ptr, size)
- __ptr_t ptr;
- size_t size;
-{
- __ptr_t result;
- int type;
- size_t block, blocks, oldlimit;
-
- if (size == 0)
- {
- free (ptr);
- return malloc (0);
- }
- else if (ptr == NULL)
- return malloc (size);
-
- if (__realloc_hook != NULL)
- return (*__realloc_hook) (ptr, size);
-
- block = BLOCK (ptr);
-
- type = _heapinfo[block].busy.type;
- switch (type)
- {
- case 0:
- /* Maybe reallocate a large block to a small fragment. */
- if (size <= BLOCKSIZE / 2)
- {
- result = malloc (size);
- if (result != NULL)
- {
- memcpy (result, ptr, size);
- free (ptr);
- return result;
- }
- }
-
- /* The new size is a large allocation as well;
- see if we can hold it in place. */
- blocks = BLOCKIFY (size);
- if (blocks < _heapinfo[block].busy.info.size)
- {
- /* The new size is smaller; return
- excess memory to the free list. */
- _heapinfo[block + blocks].busy.type = 0;
- _heapinfo[block + blocks].busy.info.size
- = _heapinfo[block].busy.info.size - blocks;
- _heapinfo[block].busy.info.size = blocks;
- free (ADDRESS (block + blocks));
- result = ptr;
- }
- else if (blocks == _heapinfo[block].busy.info.size)
- /* No size change necessary. */
- result = ptr;
- else
- {
- /* Won't fit, so allocate a new region that will.
- Free the old region first in case there is sufficient
- adjacent free space to grow without moving. */
- blocks = _heapinfo[block].busy.info.size;
- /* Prevent free from actually returning memory to the system. */
- oldlimit = _heaplimit;
- _heaplimit = 0;
- free (ptr);
- _heaplimit = oldlimit;
- result = malloc (size);
- if (result == NULL)
- {
- /* Now we're really in trouble. We have to unfree
- the thing we just freed. Unfortunately it might
- have been coalesced with its neighbors. */
- if (_heapindex == block)
- (void) malloc (blocks * BLOCKSIZE);
- else
- {
- __ptr_t previous = malloc ((block - _heapindex) * BLOCKSIZE);
- (void) malloc (blocks * BLOCKSIZE);
- free (previous);
- }
- return NULL;
- }
- if (ptr != result)
- memmove (result, ptr, blocks * BLOCKSIZE);
- }
- break;
-
- default:
- /* Old size is a fragment; type is logarithm
- to base two of the fragment size. */
- if (size > (size_t) (1 << (type - 1)) && size <= (size_t) (1 << type))
- /* The new size is the same kind of fragment. */
- result = ptr;
- else
- {
- /* The new size is different; allocate a new space,
- and copy the lesser of the new size and the old. */
- result = malloc (size);
- if (result == NULL)
- return NULL;
- memcpy (result, ptr, min (size, (size_t) 1 << type));
- free (ptr);
- }
- break;
- }
-
- return result;
-}
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