35 lines
1.1 KiB
C++
35 lines
1.1 KiB
C++
// Copyright 2021 The Chromium Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
#ifndef THIRD_PARTY_BASE_CXX17_BACKPORTS_H_
|
|
#define THIRD_PARTY_BASE_CXX17_BACKPORTS_H_
|
|
|
|
#include <stddef.h>
|
|
|
|
#include <functional>
|
|
|
|
#include "third_party/base/check.h"
|
|
|
|
namespace pdfium {
|
|
|
|
// C++14 implementation of C++17's std::clamp():
|
|
// https://en.cppreference.com/w/cpp/algorithm/clamp
|
|
// Please note that the C++ spec makes it undefined behavior to call std::clamp
|
|
// with a value of `lo` that compares greater than the value of `hi`. This
|
|
// implementation uses a CHECK to enforce this as a hard restriction.
|
|
template <typename T, typename Compare>
|
|
constexpr const T& clamp(const T& v, const T& lo, const T& hi, Compare comp) {
|
|
CHECK(!comp(hi, lo));
|
|
return comp(v, lo) ? lo : comp(hi, v) ? hi : v;
|
|
}
|
|
|
|
template <typename T>
|
|
constexpr const T& clamp(const T& v, const T& lo, const T& hi) {
|
|
return pdfium::clamp(v, lo, hi, std::less<T>{});
|
|
}
|
|
|
|
} // namespace pdfium
|
|
|
|
#endif // THIRD_PARTY_BASE_CXX17_BACKPORTS_H_
|