72 lines
2.1 KiB
C
72 lines
2.1 KiB
C
/*
|
|
* Copyright (c) 2013 Todd C. Miller <Todd.Miller@courtesan.com>
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <config.h>
|
|
|
|
#include <sys/types.h>
|
|
#include <errno.h>
|
|
#include <limits.h>
|
|
#if defined(HAVE_STDINT_H)
|
|
# include <stdint.h>
|
|
#elif defined(HAVE_INTTYPES_H)
|
|
# include <inttypes.h>
|
|
#endif
|
|
|
|
#include "missing.h"
|
|
|
|
#ifndef RSIZE_MAX
|
|
# if defined(SIZE_MAX)
|
|
# define RSIZE_MAX (SIZE_MAX >> 1)
|
|
# elif defined(__LP64__)
|
|
# define RSIZE_MAX 0x7fffffffffffffffUL
|
|
# else
|
|
# define RSIZE_MAX 0x7fffffffU
|
|
# endif
|
|
#endif
|
|
|
|
/*
|
|
* Simple implementation of C11 memset_s() function.
|
|
* We use a volatile pointer when updating the byte string.
|
|
* Most compilers will avoid optimizing away access to a
|
|
* volatile pointer, even if the pointer appears to be unused
|
|
* after the call.
|
|
*
|
|
* Note that C11 does not specify the return value on error, only
|
|
* that it be non-zero. We use EINVAL for all errors.
|
|
*/
|
|
errno_t
|
|
memset_s(void *v, rsize_t smax, int c, rsize_t n)
|
|
{
|
|
errno_t ret = 0;
|
|
volatile unsigned char *s = v;
|
|
|
|
/* Fatal runtime-constraint violations. */
|
|
if (s == NULL || smax > RSIZE_MAX) {
|
|
ret = errno = EINVAL;
|
|
goto done;
|
|
}
|
|
/* Non-fatal runtime-constraint violation, n must not exceed smax. */
|
|
if (n > smax) {
|
|
n = smax;
|
|
ret = errno = EINVAL;
|
|
}
|
|
/* Updating through a volatile pointer should not be optimized away. */
|
|
while (n--)
|
|
*s++ = (unsigned char)c;
|
|
done:
|
|
return ret;
|
|
}
|