1 24fb1a39 2025-06-02 kirill /*	$OpenBSD: reallocarray.c,v 1.1 2014/05/08 21:43:49 deraadt Exp $	*/
 2 24fb1a39 2025-06-02 kirill /*
 3 24fb1a39 2025-06-02 kirill  * Copyright (c) 2008 Otto Moerbeek <otto@drijf.net>
 4 24fb1a39 2025-06-02 kirill  *
 5 24fb1a39 2025-06-02 kirill  * Permission to use, copy, modify, and distribute this software for any
 6 24fb1a39 2025-06-02 kirill  * purpose with or without fee is hereby granted, provided that the above
 7 24fb1a39 2025-06-02 kirill  * copyright notice and this permission notice appear in all copies.
 8 24fb1a39 2025-06-02 kirill  *
 9 24fb1a39 2025-06-02 kirill  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 24fb1a39 2025-06-02 kirill  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 24fb1a39 2025-06-02 kirill  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 24fb1a39 2025-06-02 kirill  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 24fb1a39 2025-06-02 kirill  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 24fb1a39 2025-06-02 kirill  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 24fb1a39 2025-06-02 kirill  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 24fb1a39 2025-06-02 kirill  */
17 24fb1a39 2025-06-02 kirill 
18 24fb1a39 2025-06-02 kirill /* OPENBSD ORIGINAL: lib/libc/stdlib/reallocarray.c */
19 24fb1a39 2025-06-02 kirill 
20 24fb1a39 2025-06-02 kirill #include "openbsd-compat.h"
21 24fb1a39 2025-06-02 kirill 
22 24fb1a39 2025-06-02 kirill #include <sys/types.h>
23 24fb1a39 2025-06-02 kirill #include <errno.h>
24 24fb1a39 2025-06-02 kirill #include <stdint.h>
25 24fb1a39 2025-06-02 kirill #include <stdlib.h>
26 24fb1a39 2025-06-02 kirill 
27 24fb1a39 2025-06-02 kirill /*
28 24fb1a39 2025-06-02 kirill  * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX
29 24fb1a39 2025-06-02 kirill  * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW
30 24fb1a39 2025-06-02 kirill  */
31 24fb1a39 2025-06-02 kirill #define MUL_NO_OVERFLOW	(1UL << (sizeof(size_t) * 4))
32 24fb1a39 2025-06-02 kirill 
33 24fb1a39 2025-06-02 kirill void *
34 24fb1a39 2025-06-02 kirill reallocarray(void *optr, size_t nmemb, size_t size)
35 24fb1a39 2025-06-02 kirill {
36 24fb1a39 2025-06-02 kirill 	if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
37 24fb1a39 2025-06-02 kirill 	    nmemb > 0 && SIZE_MAX / nmemb < size) {
38 24fb1a39 2025-06-02 kirill 		errno = ENOMEM;
39 24fb1a39 2025-06-02 kirill 		return NULL;
40 24fb1a39 2025-06-02 kirill 	}
41 24fb1a39 2025-06-02 kirill 	return realloc(optr, size * nmemb);
42 24fb1a39 2025-06-02 kirill }