diff options
Diffstat (limited to 'openbsd-compat/reallocarray.c')
-rw-r--r-- | openbsd-compat/reallocarray.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/openbsd-compat/reallocarray.c b/openbsd-compat/reallocarray.c new file mode 100644 index 0000000..1a52acc --- /dev/null +++ b/openbsd-compat/reallocarray.c @@ -0,0 +1,46 @@ +/* $OpenBSD: reallocarray.c,v 1.2 2014/12/08 03:45:00 bcook Exp $ */ +/* + * Copyright (c) 2008 Otto Moerbeek <otto@drijf.net> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* OPENBSD ORIGINAL: lib/libc/stdlib/reallocarray.c */ + +#include "includes.h" +#ifndef HAVE_REALLOCARRAY + +#include <sys/types.h> +#include <errno.h> +#ifdef HAVE_STDINT_H +#include <stdint.h> +#endif +#include <stdlib.h> + +/* + * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX + * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW + */ +#define MUL_NO_OVERFLOW ((size_t)1 << (sizeof(size_t) * 4)) + +void * +reallocarray(void *optr, size_t nmemb, size_t size) +{ + if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && + nmemb > 0 && SIZE_MAX / nmemb < size) { + errno = ENOMEM; + return NULL; + } + return realloc(optr, size * nmemb); +} +#endif /* HAVE_REALLOCARRAY */ |