1/*
2 *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
3 *
4 *  Use of this source code is governed by a BSD-style license
5 *  that can be found in the LICENSE file in the root of the source
6 *  tree. An additional intellectual property rights grant can be found
7 *  in the file PATENTS.  All contributing project authors may
8 *  be found in the AUTHORS file in the root of the source tree.
9 */
10
11#ifndef WEBRTC_BASE_ARRAYSIZE_H_
12#define WEBRTC_BASE_ARRAYSIZE_H_
13
14#include <stddef.h>
15
16// This file defines the arraysize() macro and is derived from Chromium's
17// base/macros.h.
18
19// The arraysize(arr) macro returns the # of elements in an array arr.
20// The expression is a compile-time constant, and therefore can be
21// used in defining new arrays, for example.  If you use arraysize on
22// a pointer by mistake, you will get a compile-time error.
23
24// This template function declaration is used in defining arraysize.
25// Note that the function doesn't need an implementation, as we only
26// use its type.
27template <typename T, size_t N> char (&ArraySizeHelper(T (&array)[N]))[N];
28
29#define arraysize(array) (sizeof(ArraySizeHelper(array)))
30
31#endif  // WEBRTC_BASE_ARRAYSIZE_H_
32