1 /* $OpenBSD: reallocarray.c,v 1.3 2022/01/08 06:49:41 guenther Exp $ */
2 /*
3 * Copyright (c) 2008 Otto Moerbeek <otto@drijf.net>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 #include <sys/types.h>
19 #include <stdint.h>
20
21 #include "util.h"
22
23 /*
24 * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX
25 * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW
26 */
27 #define MUL_NO_OVERFLOW (1UL << (sizeof(size_t) * 4))
28
29 void *
_dl_reallocarray(void * optr,size_t nmemb,size_t size)30 _dl_reallocarray(void *optr, size_t nmemb, size_t size)
31 {
32 if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
33 nmemb > 0 && SIZE_MAX / nmemb < size)
34 _dl_die("reallocarray overflow");
35 return _dl_realloc(optr, size * nmemb);
36 }
37