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Index: head/libexec/rtld-elf/rtld_malloc.c
===================================================================
--- head/libexec/rtld-elf/rtld_malloc.c
+++ head/libexec/rtld-elf/rtld_malloc.c
@@ -85,7 +85,6 @@
static void morecore(int bucket);
static int morepages(int n);
-static int findbucket(union overhead *freep, int srchlen);
#define MAGIC 0xef /* magic # on accounting info */
@@ -248,19 +247,6 @@
nextf[size] = op;
}
-/*
- * When a program attempts "storage compaction" as mentioned in the
- * old malloc man page, it realloc's an already freed block. Usually
- * this is the last block it freed; occasionally it might be farther
- * back. We have to search all the free lists for the block in order
- * to determine its bucket: 1st we make one pass through the lists
- * checking only the first block in each; if that fails we search
- * ``realloc_srchlen'' blocks in each list for a match (the variable
- * is extern so the caller can modify it). If that fails we just copy
- * however many bytes was given to realloc() and hope it's not huge.
- */
-static int realloc_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */
-
void *
__crt_realloc(void *cp, size_t nbytes)
{
@@ -268,78 +254,33 @@
int i;
union overhead *op;
char *res;
- int was_alloced = 0;
if (cp == NULL)
return (__crt_malloc(nbytes));
op = (union overhead *)((caddr_t)cp - sizeof (union overhead));
- if (op->ov_magic == MAGIC) {
- was_alloced++;
- i = op->ov_index;
- } else {
- /*
- * Already free, doing "compaction".
- *
- * Search for the old block of memory on the
- * free list. First, check the most common
- * case (last element free'd), then (this failing)
- * the last ``realloc_srchlen'' items free'd.
- * If all lookups fail, then assume the size of
- * the memory block being realloc'd is the
- * largest possible (so that all "nbytes" of new
- * memory are copied into). Note that this could cause
- * a memory fault if the old area was tiny, and the moon
- * is gibbous. However, that is very unlikely.
- */
- if ((i = findbucket(op, 1)) < 0 &&
- (i = findbucket(op, realloc_srchlen)) < 0)
- i = NBUCKETS;
- }
+ if (op->ov_magic != MAGIC)
+ return (NULL); /* Double-free or bad argument */
+ i = op->ov_index;
onb = 1 << (i + 3);
if (onb < (u_int)pagesz)
onb -= sizeof(*op);
else
onb += pagesz - sizeof(*op);
/* avoid the copy if same size block */
- if (was_alloced) {
- if (i) {
- i = 1 << (i + 2);
- if (i < pagesz)
- i -= sizeof(*op);
- else
- i += pagesz - sizeof(*op);
- }
- if (nbytes <= onb && nbytes > (size_t)i)
- return (cp);
- __crt_free(cp);
+ if (i != 0) {
+ i = 1 << (i + 2);
+ if (i < pagesz)
+ i -= sizeof(*op);
+ else
+ i += pagesz - sizeof(*op);
}
+ if (nbytes <= onb && nbytes > (size_t)i)
+ return (cp);
if ((res = __crt_malloc(nbytes)) == NULL)
return (NULL);
- if (cp != res) /* common optimization if "compacting" */
- bcopy(cp, res, (nbytes < onb) ? nbytes : onb);
+ bcopy(cp, res, (nbytes < onb) ? nbytes : onb);
+ __crt_free(cp);
return (res);
-}
-
-/*
- * Search ``srchlen'' elements of each free list for a block whose
- * header starts at ``freep''. If srchlen is -1 search the whole list.
- * Return bucket number, or -1 if not found.
- */
-static int
-findbucket(union overhead *freep, int srchlen)
-{
- union overhead *p;
- int i, j;
-
- for (i = 0; i < NBUCKETS; i++) {
- j = 0;
- for (p = nextf[i]; p && j != srchlen; p = p->ov_next) {
- if (p == freep)
- return (i);
- j++;
- }
- }
- return (-1);
}
static int

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