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/*
This is a version (aka dlmalloc) of malloc/free/realloc written by
Doug Lea and released to the public domain. Use, modify, and
redistribute this code without permission or acknowledgement in any
way you wish. Send questions, comments, complaints, performance
data, etc to dl@cs.oswego.edu
VERSION 2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee)
Note: There may be an updated version of this malloc obtainable at
ftp://gee.cs.oswego.edu/pub/misc/malloc.c
Check before installing!
Hacked up for uClibc by Erik Andersen <andersen@codepoet.org>
*/
#include "malloc.h"
/* ------------------------------ calloc ------------------------------ */
void* calloc(size_t n_elements, size_t elem_size)
{
mchunkptr p;
unsigned long clearsize;
unsigned long nclears;
size_t size, *d;
void* mem;
/* guard vs integer overflow, but allow nmemb
* to fall through and call malloc(0) */
size = n_elements * elem_size;
if (n_elements && elem_size != (size / n_elements)) {
__set_errno(ENOMEM);
return NULL;
}
__MALLOC_LOCK;
mem = malloc(size);
if (mem != 0) {
p = mem2chunk(mem);
if (!chunk_is_mmapped(p))
{
/*
Unroll clear of <= 36 bytes (72 if 8byte sizes)
We know that contents have an odd number of
size_t-sized words; minimally 3.
*/
d = (size_t*)mem;
clearsize = chunksize(p) - (sizeof(size_t));
nclears = clearsize / sizeof(size_t);
assert(nclears >= 3);
if (nclears > 9)
memset(d, 0, clearsize);
else {
*(d+0) = 0;
*(d+1) = 0;
*(d+2) = 0;
if (nclears > 4) {
*(d+3) = 0;
*(d+4) = 0;
if (nclears > 6) {
*(d+5) = 0;
*(d+6) = 0;
if (nclears > 8) {
*(d+7) = 0;
*(d+8) = 0;
}
}
}
}
}
#if 0
else
{
/* Standard unix mmap using /dev/zero clears memory so calloc
* doesn't need to actually zero anything....
*/
d = (size_t*)mem;
/* Note the additional (sizeof(size_t)) */
clearsize = chunksize(p) - 2*(sizeof(size_t));
memset(d, 0, clearsize);
}
#endif
}
__MALLOC_UNLOCK;
return mem;
}
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