1 | /* $OpenBSD: reallocarray.c,v 1.3 2015/09/13 08:31:47 guenther Exp $ */ |
2 | /* |
3 | * Copyright (c) 2008 Otto Moerbeek <[email protected]> |
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 <errno.h> |
20 | #include <stdint.h> |
21 | #include <stdlib.h> |
22 | |
23 | #include "compat.h" |
24 | |
25 | /* |
26 | * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX |
27 | * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW |
28 | */ |
29 | #define MUL_NO_OVERFLOW ((size_t)1 << (sizeof(size_t) * 4)) |
30 | |
31 | void * |
32 | reallocarray(void *optr, size_t nmemb, size_t size) |
33 | { |
34 | if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && |
35 | nmemb > 0 && SIZE_MAX / nmemb < size) { |
36 | errno = ENOMEM; |
37 | return NULL; |
38 | } |
39 | return realloc(optr, size * nmemb); |
40 | } |
41 | |