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// Copyright 2014 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 BASE_SAFE_CONVERSIONS_H_
#define BASE_SAFE_CONVERSIONS_H_
#include <limits>
#include "../logging.h"
#include "safe_conversions_impl.h"
namespace base {
// Convenience function that returns true if the supplied value is in range
// for the destination type.
template <typename Dst, typename Src>
inline bool IsValueInRangeForNumericType(Src value) {
return internal::DstRangeRelationToSrcRange<Dst>(value) ==
internal::RANGE_VALID;
}
// checked_cast<> is analogous to static_cast<> for numeric types,
// except that it CHECKs that the specified numeric conversion will not
// overflow or underflow. NaN source will always trigger a CHECK.
template <typename Dst, typename Src>
inline Dst checked_cast(Src value) {
CHECK(IsValueInRangeForNumericType<Dst>(value));
return static_cast<Dst>(value);
}
// saturated_cast<> is analogous to static_cast<> for numeric types, except
// that the specified numeric conversion will saturate rather than overflow or
// underflow. NaN assignment to an integral will trigger a CHECK condition.
template <typename Dst, typename Src>
inline Dst saturated_cast(Src value) {
// Optimization for floating point values, which already saturate.
if (std::numeric_limits<Dst>::is_iec559)
return static_cast<Dst>(value);
switch (internal::DstRangeRelationToSrcRange<Dst>(value)) {
case internal::RANGE_VALID:
return static_cast<Dst>(value);
case internal::RANGE_UNDERFLOW:
return std::numeric_limits<Dst>::min();
case internal::RANGE_OVERFLOW:
return std::numeric_limits<Dst>::max();
// Should fail only on attempting to assign NaN to a saturated integer.
case internal::RANGE_INVALID:
CHECK(false);
return std::numeric_limits<Dst>::max();
}
NOTREACHED();
return static_cast<Dst>(value);
}
} // namespace base
#endif // BASE_SAFE_CONVERSIONS_H_
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