61 lines
1.8 KiB
C
61 lines
1.8 KiB
C
|
/*
|
||
|
|
* Copyright 2019 The WebRTC Project Authors. All rights reserved.
|
||
|
|
*
|
||
|
|
* Use of this source code is governed by a BSD-style license
|
||
|
|
* that can be found in the LICENSE file in the root of the source
|
||
|
|
* tree. An additional intellectual property rights grant can be found
|
||
|
|
* in the file PATENTS. All contributing project authors may
|
||
|
|
* be found in the AUTHORS file in the root of the source tree.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef RTC_BASE_NUMERICS_DIVIDE_ROUND_H_
|
||
|
|
#define RTC_BASE_NUMERICS_DIVIDE_ROUND_H_
|
||
|
|
|
||
|
|
#include <type_traits>
|
||
|
|
|
||
|
|
#include "rtc_base/checks.h"
|
||
|
|
#include "rtc_base/numerics/safe_compare.h"
|
||
|
|
|
||
|
|
namespace webrtc {
|
||
|
|
|
||
|
|
template <typename Dividend, typename Divisor>
|
||
|
|
inline auto constexpr DivideRoundUp(Dividend dividend, Divisor divisor) {
|
||
|
|
static_assert(std::is_integral<Dividend>(), "");
|
||
|
|
static_assert(std::is_integral<Divisor>(), "");
|
||
|
|
RTC_DCHECK_GE(dividend, 0);
|
||
|
|
RTC_DCHECK_GT(divisor, 0);
|
||
|
|
|
||
|
|
auto quotient = dividend / divisor;
|
||
|
|
auto remainder = dividend % divisor;
|
||
|
|
return quotient + (remainder > 0 ? 1 : 0);
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename Dividend, typename Divisor>
|
||
|
|
inline auto constexpr DivideRoundToNearest(Dividend dividend, Divisor divisor) {
|
||
|
|
static_assert(std::is_integral<Dividend>(), "");
|
||
|
|
static_assert(std::is_integral<Divisor>(), "");
|
||
|
|
RTC_DCHECK_GT(divisor, 0);
|
||
|
|
|
||
|
|
if (dividend < Dividend{0}) {
|
||
|
|
auto half_of_divisor = divisor / 2;
|
||
|
|
auto quotient = dividend / divisor;
|
||
|
|
auto remainder = dividend % divisor;
|
||
|
|
if (rtc::SafeGt(-remainder, half_of_divisor)) {
|
||
|
|
--quotient;
|
||
|
|
}
|
||
|
|
return quotient;
|
||
|
|
}
|
||
|
|
|
||
|
|
auto half_of_divisor = (divisor - 1) / 2;
|
||
|
|
auto quotient = dividend / divisor;
|
||
|
|
auto remainder = dividend % divisor;
|
||
|
|
if (rtc::SafeGt(remainder, half_of_divisor)) {
|
||
|
|
++quotient;
|
||
|
|
}
|
||
|
|
return quotient;
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace webrtc
|
||
|
|
|
||
|
|
#endif // RTC_BASE_NUMERICS_DIVIDE_ROUND_H_
|