Files
shadow/lib/sizeof.h
Alejandro Colomar e299942189 sizeof.h: Add SIZEOF_ARRAY() macro
This makes it safe to call sizeof() on an array.  Calling sizeof()
directly on an array is dangerous, because if the array changes to be a
pointer, the behavior will unexpectedly change.  It's the same problem
as with NITEMS().

Link: <https://stackoverflow.com/a/57537491>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
2023-09-01 09:39:23 +02:00

25 lines
506 B
C

/*
* SPDX-FileCopyrightText: 2022-2023, Alejandro Colomar <alx@kernel.org>
* SPDX-License-Identifier: BSD-3-Clause
*/
#ifndef SHADOW_INCLUDE_LIBMISC_SIZEOF_H_
#define SHADOW_INCLUDE_LIBMISC_SIZEOF_H_
#include <config.h>
#include <limits.h>
#include "must_be.h"
#define WIDTHOF(x) (sizeof(x) * CHAR_BIT)
#define SIZEOF_ARRAY(a) (sizeof(a) + must_be_array(a))
#define NITEMS(a) (SIZEOF_ARRAY((a)) / sizeof((a)[0]))
#define STRLEN(s) (NITEMS(s) - 1)
#endif // include guard