1282314Sbapt/* $OpenBSD: reallocarray.c,v 1.2 2014/12/08 03:45:00 bcook Exp $ */ 2282314Sbapt/* 3282314Sbapt * Copyright (c) 2008 Otto Moerbeek <otto@drijf.net> 4282314Sbapt * 5282314Sbapt * Permission to use, copy, modify, and distribute this software for any 6282314Sbapt * purpose with or without fee is hereby granted, provided that the above 7282314Sbapt * copyright notice and this permission notice appear in all copies. 8282314Sbapt * 9282314Sbapt * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10282314Sbapt * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11282314Sbapt * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12282314Sbapt * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13282314Sbapt * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14282314Sbapt * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15282314Sbapt * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16282314Sbapt */ 17282314Sbapt 18282314Sbapt#include <sys/cdefs.h> 19282314Sbapt__FBSDID("$FreeBSD$"); 20282314Sbapt 21282314Sbapt#include <sys/types.h> 22282314Sbapt#include <errno.h> 23282314Sbapt#include <stdint.h> 24282314Sbapt#include <stdlib.h> 25282314Sbapt 26282314Sbapt/* 27282314Sbapt * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX 28282314Sbapt * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW 29282314Sbapt */ 30282314Sbapt#define MUL_NO_OVERFLOW ((size_t)1 << (sizeof(size_t) * 4)) 31282314Sbapt 32282314Sbaptvoid * 33282314Sbaptreallocarray(void *optr, size_t nmemb, size_t size) 34282314Sbapt{ 35282314Sbapt 36282314Sbapt if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && 37282314Sbapt nmemb > 0 && SIZE_MAX / nmemb < size) { 38282314Sbapt errno = ENOMEM; 39282314Sbapt return (NULL); 40282314Sbapt } 41282314Sbapt return (realloc(optr, size * nmemb)); 42282314Sbapt} 43