Damien Miller | 7de5991 | 2014-12-18 11:44:06 +1100 | [diff] [blame^] | 1 | /* $OpenBSD: reallocarray.c,v 1.2 2014/12/08 03:45:00 bcook Exp $ */ |
Darren Tucker | 642652d | 2014-12-10 01:32:23 +1100 | [diff] [blame] | 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 | /* OPENBSD ORIGINAL: lib/libc/stdlib/reallocarray.c */ |
| 19 | |
| 20 | #include "includes.h" |
| 21 | #ifndef HAVE_REALLOCARRAY |
| 22 | |
| 23 | #include <sys/types.h> |
| 24 | #include <errno.h> |
| 25 | #include <stdint.h> |
| 26 | #include <stdlib.h> |
| 27 | |
| 28 | /* |
| 29 | * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX |
| 30 | * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW |
| 31 | */ |
Damien Miller | 7de5991 | 2014-12-18 11:44:06 +1100 | [diff] [blame^] | 32 | #define MUL_NO_OVERFLOW ((size_t)1 << (sizeof(size_t) * 4)) |
Darren Tucker | 642652d | 2014-12-10 01:32:23 +1100 | [diff] [blame] | 33 | |
| 34 | void * |
| 35 | reallocarray(void *optr, size_t nmemb, size_t size) |
| 36 | { |
| 37 | if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && |
| 38 | nmemb > 0 && SIZE_MAX / nmemb < size) { |
| 39 | errno = ENOMEM; |
| 40 | return NULL; |
| 41 | } |
| 42 | return realloc(optr, size * nmemb); |
| 43 | } |
| 44 | #endif /* HAVE_REALLOCARRAY */ |