1/* The array_length and array_end macros.
2 Copyright (C) 2017-2020 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#ifndef _ARRAY_LENGTH_H
20#define _ARRAY_LENGTH_H
21
22/* array_length (VAR) is the number of elements in the array VAR. VAR
23 must evaluate to an array, not a pointer. */
24#define array_length(var) \
25 (sizeof (var) / sizeof ((var)[0]) \
26 + 0 * sizeof (struct { \
27 _Static_assert (!__builtin_types_compatible_p \
28 (__typeof (var), __typeof (&(var)[0])), \
29 "argument must be an array"); \
30 }))
31
32/* array_end (VAR) is a pointer one past the end of the array VAR.
33 VAR must evaluate to an array, not a pointer. */
34#define array_end(var) (&(var)[array_length (var)])
35
36#endif /* _ARRAY_LENGTH_H */
37