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-rw-r--r--mmalloc/mmalloc.c337
1 files changed, 0 insertions, 337 deletions
diff --git a/mmalloc/mmalloc.c b/mmalloc/mmalloc.c
deleted file mode 100644
index 7c60fe2d57b..00000000000
--- a/mmalloc/mmalloc.c
+++ /dev/null
@@ -1,337 +0,0 @@
-/* Memory allocator `malloc'.
- Copyright 1990, 1991, 1992 Free Software Foundation
-
- Written May 1989 by Mike Haertel.
- Heavily modified Mar 1992 by Fred Fish for mmap'd version.
-
-The GNU C 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.
-
-The GNU C 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 the GNU C Library; see the file COPYING.LIB. If
-not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, 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. */
-
-#include <string.h> /* Prototypes for memcpy, memmove, memset, etc */
-
-#include "mmprivate.h"
-
-/* Prototypes for local functions */
-
-static int initialize PARAMS ((struct mdesc *));
-static PTR morecore PARAMS ((struct mdesc *, size_t));
-static PTR align PARAMS ((struct mdesc *, size_t));
-
-/* Aligned allocation. */
-
-static PTR
-align (mdp, size)
- struct mdesc *mdp;
- size_t size;
-{
- PTR result;
- unsigned long int adj;
-
- result = mdp -> morecore (mdp, size);
- adj = RESIDUAL (result, BLOCKSIZE);
- if (adj != 0)
- {
- adj = BLOCKSIZE - adj;
- mdp -> morecore (mdp, adj);
- result = (char *) result + adj;
- }
- return (result);
-}
-
-/* Set everything up and remember that we have. */
-
-static int
-initialize (mdp)
- struct mdesc *mdp;
-{
- mdp -> heapsize = HEAP / BLOCKSIZE;
- mdp -> heapinfo = (malloc_info *)
- align (mdp, mdp -> heapsize * sizeof (malloc_info));
- if (mdp -> heapinfo == NULL)
- {
- return (0);
- }
- memset ((PTR)mdp -> heapinfo, 0, mdp -> heapsize * sizeof (malloc_info));
- mdp -> heapinfo[0].free.size = 0;
- mdp -> heapinfo[0].free.next = mdp -> heapinfo[0].free.prev = 0;
- mdp -> heapindex = 0;
- mdp -> heapbase = (char *) mdp -> heapinfo;
- mdp -> flags |= MMALLOC_INITIALIZED;
- return (1);
-}
-
-/* Get neatly aligned memory, initializing or
- growing the heap info table as necessary. */
-
-static PTR
-morecore (mdp, size)
- struct mdesc *mdp;
- size_t size;
-{
- PTR result;
- malloc_info *newinfo, *oldinfo;
- size_t newsize;
-
- result = align (mdp, size);
- if (result == NULL)
- {
- return (NULL);
- }
-
- /* Check if we need to grow the info table. */
- if ((size_t) BLOCK ((char *) result + size) > mdp -> heapsize)
- {
- newsize = mdp -> heapsize;
- while ((size_t) BLOCK ((char *) result + size) > newsize)
- {
- newsize *= 2;
- }
- newinfo = (malloc_info *) align (mdp, newsize * sizeof (malloc_info));
- if (newinfo == NULL)
- {
- mdp -> morecore (mdp, -size);
- return (NULL);
- }
- memset ((PTR) newinfo, 0, newsize * sizeof (malloc_info));
- memcpy ((PTR) newinfo, (PTR) mdp -> heapinfo,
- mdp -> heapsize * sizeof (malloc_info));
- oldinfo = mdp -> heapinfo;
- newinfo[BLOCK (oldinfo)].busy.type = 0;
- newinfo[BLOCK (oldinfo)].busy.info.size
- = BLOCKIFY (mdp -> heapsize * sizeof (malloc_info));
- mdp -> heapinfo = newinfo;
- __mmalloc_free (mdp, (PTR)oldinfo);
- mdp -> heapsize = newsize;
- }
-
- mdp -> heaplimit = BLOCK ((char *) result + size);
- return (result);
-}
-
-/* Allocate memory from the heap. */
-
-PTR
-mmalloc (md, size)
- PTR md;
- size_t size;
-{
- struct mdesc *mdp;
- PTR result;
- size_t block, blocks, lastblocks, start;
- register size_t i;
- struct list *next;
- register size_t log;
-
- if (size == 0)
- {
- return (NULL);
- }
-
- mdp = MD_TO_MDP (md);
-
- if (mdp -> mmalloc_hook != NULL)
- {
- return ((*mdp -> mmalloc_hook) (md, size));
- }
-
- if (!(mdp -> flags & MMALLOC_INITIALIZED))
- {
- if (!initialize (mdp))
- {
- 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. */
- log = 1;
- --size;
- while ((size /= 2) != 0)
- {
- ++log;
- }
-
- /* Look in the fragment lists for a
- free fragment of the desired size. */
- next = mdp -> 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) next;
- next -> prev -> next = next -> next;
- if (next -> next != NULL)
- {
- next -> next -> prev = next -> prev;
- }
- block = BLOCK (result);
- if (--mdp -> heapinfo[block].busy.info.frag.nfree != 0)
- {
- mdp -> heapinfo[block].busy.info.frag.first =
- RESIDUAL (next -> next, BLOCKSIZE) >> log;
- }
-
- /* Update the statistics. */
- mdp -> heapstats.chunks_used++;
- mdp -> heapstats.bytes_used += 1 << log;
- mdp -> heapstats.chunks_free--;
- mdp -> heapstats.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 = mmalloc (md, BLOCKSIZE);
- if (result == NULL)
- {
- return (NULL);
- }
-
- /* 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 = mdp -> fraghead[log].next;
- next -> prev = &mdp -> 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);
- mdp -> heapinfo[block].busy.type = log;
- mdp -> heapinfo[block].busy.info.frag.nfree = i - 1;
- mdp -> heapinfo[block].busy.info.frag.first = i - 1;
-
- mdp -> heapstats.chunks_free += (BLOCKSIZE >> log) - 1;
- mdp -> heapstats.bytes_free += BLOCKSIZE - (1 << log);
- mdp -> heapstats.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 = MALLOC_SEARCH_START;
- while (mdp -> heapinfo[block].free.size < blocks)
- {
- block = mdp -> 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 = mdp -> heapinfo[0].free.prev;
- lastblocks = mdp -> heapinfo[block].free.size;
- if (mdp -> heaplimit != 0 &&
- block + lastblocks == mdp -> heaplimit &&
- mdp -> morecore (mdp, 0) == ADDRESS(block + lastblocks) &&
- (morecore (mdp, (blocks - lastblocks) * BLOCKSIZE)) != NULL)
- {
- /* Which block we are extending (the `final free
- block' referred to above) might have changed, if
- it got combined with a freed info table. */
- block = mdp -> heapinfo[0].free.prev;
-
- mdp -> heapinfo[block].free.size += (blocks - lastblocks);
- mdp -> heapstats.bytes_free +=
- (blocks - lastblocks) * BLOCKSIZE;
- continue;
- }
- result = morecore(mdp, blocks * BLOCKSIZE);
- if (result == NULL)
- {
- return (NULL);
- }
- block = BLOCK (result);
- mdp -> heapinfo[block].busy.type = 0;
- mdp -> heapinfo[block].busy.info.size = blocks;
- mdp -> heapstats.chunks_used++;
- mdp -> heapstats.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 (mdp -> heapinfo[block].free.size > blocks)
- {
- /* The block we found has a bit left over,
- so relink the tail end back into the free list. */
- mdp -> heapinfo[block + blocks].free.size
- = mdp -> heapinfo[block].free.size - blocks;
- mdp -> heapinfo[block + blocks].free.next
- = mdp -> heapinfo[block].free.next;
- mdp -> heapinfo[block + blocks].free.prev
- = mdp -> heapinfo[block].free.prev;
- mdp -> heapinfo[mdp -> heapinfo[block].free.prev].free.next
- = mdp -> heapinfo[mdp -> heapinfo[block].free.next].free.prev
- = mdp -> heapindex = block + blocks;
- }
- else
- {
- /* The block exactly matches our requirements,
- so just remove it from the list. */
- mdp -> heapinfo[mdp -> heapinfo[block].free.next].free.prev
- = mdp -> heapinfo[block].free.prev;
- mdp -> heapinfo[mdp -> heapinfo[block].free.prev].free.next
- = mdp -> heapindex = mdp -> heapinfo[block].free.next;
- mdp -> heapstats.chunks_free--;
- }
-
- mdp -> heapinfo[block].busy.type = 0;
- mdp -> heapinfo[block].busy.info.size = blocks;
- mdp -> heapstats.chunks_used++;
- mdp -> heapstats.bytes_used += blocks * BLOCKSIZE;
- mdp -> heapstats.bytes_free -= blocks * BLOCKSIZE;
- }
-
- return (result);
-}
-
-/* When using this package, provide a version of malloc/realloc/free built
- on top of it, so that if we use the default sbrk() region we will not
- collide with another malloc package trying to do the same thing, if
- the application contains any "hidden" calls to malloc/realloc/free (such
- as inside a system library). */
-
-PTR
-malloc (size)
- size_t size;
-{
- PTR result;
-
- result = mmalloc ((PTR) NULL, size);
- return (result);
-}
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