1 | /* $OpenBSD: reallocarray.c,v 1.2 2014/12/08 03:45:00 bcook Exp $ */ |
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2 | /* |
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3 | * Copyright (c) 2008 Otto Moerbeek <otto@drijf.net> |
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4 | * |
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5 | * Permission to use, copy, modify, and distribute this software for any |
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6 | * purpose with or without fee is hereby granted, provided that the above |
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7 | * copyright notice and this permission notice appear in all copies. |
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8 | * |
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9 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
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10 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
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11 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
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12 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
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13 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
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14 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
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15 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
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16 | */ |
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17 | |
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18 | #include <sys/cdefs.h> |
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19 | __FBSDID("$FreeBSD: head/lib/libc/stdlib/reallocarray.c 282314 2015-05-01 18:32:16Z bapt $"); |
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20 | |
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21 | #include <sys/types.h> |
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22 | #include <errno.h> |
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23 | #include <stdint.h> |
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24 | #include <stdlib.h> |
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25 | |
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26 | /* |
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27 | * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX |
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28 | * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW |
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29 | */ |
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30 | #define MUL_NO_OVERFLOW ((size_t)1 << (sizeof(size_t) * 4)) |
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31 | |
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32 | void * |
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33 | reallocarray(void *optr, size_t nmemb, size_t size) |
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34 | { |
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35 | |
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36 | if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && |
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37 | nmemb > 0 && SIZE_MAX / nmemb < size) { |
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38 | errno = ENOMEM; |
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39 | return (NULL); |
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40 | } |
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41 | return (realloc(optr, size * nmemb)); |
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42 | } |
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