-/* Change the size of a block allocated by `mmalloc'.
- Copyright 1990, 1991 Free Software Foundation
- Written May 1989 by Mike Haertel. */
+/* Change the size of a block allocated by `mmalloc'. */
-/* Copyright (c) 2010. The SimGrid Team.
+/* Copyright (c) 2010-2014. The SimGrid Team.
* All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
-#include <string.h> /* Prototypes for memcpy, memmove, memset, etc */
+/* Copyright 1990, 1991 Free Software Foundation
+ Written May 1989 by Mike Haertel. */
+
+#include <string.h> /* Prototypes for memcpy, memmove, memset, etc */
+#include <stdlib.h> /* abort */
#include "mmprivate.h"
new region. This module has incestuous knowledge of the
internals of both mfree and mmalloc. */
-void*
-mrealloc (void *md, void *ptr, size_t size)
+void *mrealloc(xbt_mheap_t mdp, void *ptr, size_t size)
{
- struct mdesc *mdp;
- void* result;
+ void *result;
int type;
size_t block, blocks, oldlimit;
- if (size == 0)
- {
- mfree (md, ptr);
- return (mmalloc (md, 0));
- }
- else if (ptr == NULL)
- {
- return (mmalloc (md, size));
+ /* Only keep real realloc, and reroute hidden malloc and free to the relevant functions */
+ if (size == 0) {
+ mfree(mdp, ptr);
+ return mmalloc(mdp, 0);
+ } else if (ptr == NULL) {
+ return mmalloc(mdp, size);
+ }
+
+ //printf("(%s)realloc %p to %d...",xbt_thread_self_name(),ptr,(int)size);
+
+ if ((char *) ptr < (char *) mdp->heapbase || BLOCK(ptr) > mdp->heapsize) {
+ printf
+ ("FIXME. Ouch, this pointer is not mine, refusing to proceed (another solution would be to malloc it instead of reallocing it, see source code)\n");
+ result = mmalloc(mdp, size);
+ abort();
+ return result;
+ }
+
+ size_t requested_size = size; // The amount of memory requested by user, for real
+
+ /* Work even if the user was stupid enough to ask a ridicullously small block (even 0-length),
+ * ie return a valid block that can be realloced and freed.
+ * glibc malloc does not use this trick but return a constant pointer, but we need to enlist the free fragments later on.
+ */
+ if (size < SMALLEST_POSSIBLE_MALLOC)
+ size = SMALLEST_POSSIBLE_MALLOC;
+
+ block = BLOCK(ptr);
+
+ type = mdp->heapinfo[block].type;
+
+ switch (type) {
+ case -1:
+ fprintf(stderr, "Asked realloc a fragment coming from a *free* block. I'm puzzled.\n");
+ abort();
+ break;
+
+ case 0:
+ /* Maybe reallocate a large block to a small fragment. */
+
+ if (size <= BLOCKSIZE / 2) { // Full block -> Fragment; no need to optimize for time
+
+ result = mmalloc(mdp, size);
+ if (result != NULL) { // useless (mmalloc never returns NULL), but harmless
+ memcpy(result, ptr, requested_size);
+ mfree(mdp, ptr);
+ return (result);
+ }
}
- mdp = MD_TO_MDP (md);
-
- if (mdp -> mrealloc_hook != NULL)
- {
- return ((*mdp -> mrealloc_hook) (md, ptr, size));
+ /* Full blocks -> Full blocks; see if we can hold it in place. */
+ blocks = BLOCKIFY(size);
+ if (blocks < mdp->heapinfo[block].busy_block.size) {
+ int it;
+ /* The new size is smaller; return excess memory to the free list. */
+ //printf("(%s) return excess memory...",xbt_thread_self_name());
+ for (it= block+blocks; it< mdp->heapinfo[block].busy_block.size ; it++){
+ mdp->heapinfo[it].type = 0; // FIXME that should be useless, type should already be 0 here
+ mdp->heapinfo[it].busy_block.ignore = 0;
+ }
+
+ mdp->heapinfo[block + blocks].busy_block.size
+ = mdp->heapinfo[block].busy_block.size - blocks;
+ mfree(mdp, ADDRESS(block + blocks));
+
+ mdp->heapinfo[block].busy_block.size = blocks;
+ mdp->heapinfo[block].busy_block.busy_size = requested_size;
+ mdp->heapinfo[block].busy_block.ignore = 0;
+
+ result = ptr;
+ } else if (blocks == mdp->heapinfo[block].busy_block.size) {
+
+ /* No block size change necessary; only update the requested size */
+ result = ptr;
+ mdp->heapinfo[block].busy_block.busy_size = requested_size;
+ mdp->heapinfo[block].busy_block.ignore = 0;
+
+ } 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.
+ This trick mandates using a specific version of mmalloc that does not memset the memory to 0 after
+ action for obvious reasons. */
+ blocks = mdp->heapinfo[block].busy_block.size;
+ /* Prevent free from actually returning memory to the system. */
+ oldlimit = mdp->heaplimit;
+ mdp->heaplimit = 0;
+ mfree(mdp, ptr);
+ mdp->heaplimit = oldlimit;
+
+ result = mmalloc_no_memset(mdp, requested_size);
+ //fprintf(stderr,"remalloc(%zu)~>%p\n",requested_size,result);
+
+ if (ptr != result)
+ memmove(result, ptr, blocks * BLOCKSIZE);
+ /* FIXME: we should memset the end of the recently area */
}
+ break;
- block = BLOCK (ptr);
-
- type = mdp -> heapinfo[block].busy.type;
- switch (type)
- {
- case 0:
- /* Maybe reallocate a large block to a small fragment. */
- if (size <= BLOCKSIZE / 2)
- {
- result = mmalloc (md, size);
- if (result != NULL)
- {
- memcpy (result, ptr, size);
- mfree (md, 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 < mdp -> heapinfo[block].busy.info.size)
- {
- /* The new size is smaller; return excess memory to the free list. */
- mdp -> heapinfo[block + blocks].busy.type = 0;
- mdp -> heapinfo[block + blocks].busy.info.size
- = mdp -> heapinfo[block].busy.info.size - blocks;
- mdp -> heapinfo[block].busy.info.size = blocks;
- mfree (md, ADDRESS (block + blocks));
- result = ptr;
- }
- else if (blocks == mdp -> 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 = mdp -> heapinfo[block].busy.info.size;
- /* Prevent free from actually returning memory to the system. */
- oldlimit = mdp -> heaplimit;
- mdp -> heaplimit = 0;
- mfree (md, ptr);
- mdp -> heaplimit = oldlimit;
- result = mmalloc (md, size);
- if (result == NULL)
- {
- mmalloc (md, blocks * BLOCKSIZE);
- 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 = mmalloc (md, size);
- if (result == NULL)
- {
- return (NULL);
- }
- memcpy (result, ptr, MIN (size, (size_t) 1 << type));
- mfree (md, ptr);
- }
- break;
- }
+ default: /* Fragment -> ??; type=logarithm to base two of the fragment size. */
- return (result);
-}
+ if (size > (size_t) (1 << (type - 1)) && size <= (size_t) (1 << type)) {
+ /* The new size is the same kind of fragment. */
+ //printf("(%s) new size is same kind of fragment...",xbt_thread_self_name());
-/* Useless prototype to make gcc happy */
-void *realloc (void *ptr, size_t size);
+ result = ptr;
+ int frag_nb = RESIDUAL(result, BLOCKSIZE) >> type;
+ mdp->heapinfo[block].busy_frag.frag_size[frag_nb] = requested_size;
+ mdp->heapinfo[block].busy_frag.ignore[frag_nb] = 0;
-/* 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).
- FIXME: disabled for now */
+ } else { /* fragment -> Either other fragment, or block */
+ /* The new size is different; allocate a new space,
+ and copy the lesser of the new size and the old. */
+ //printf("(%s) new size is different...",xbt_thread_self_name());
-//void * realloc (void *ptr, size_t size) {
-// void* result;
+ result = mmalloc(mdp, requested_size);
-// result = mrealloc (NULL, ptr, size);
-// return (result);
-//}
+ memcpy(result, ptr, MIN(requested_size, (size_t) 1 << type));
+ mfree(mdp, ptr);
+ }
+ break;
+ }
+ //printf("(%s) Done reallocing: %p\n",xbt_thread_self_name(),result);fflush(stdout);
+ return (result);
+}