| /* |
| * libjingle |
| * Copyright 2014, Google Inc. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright notice, |
| * this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright notice, |
| * this list of conditions and the following disclaimer in the documentation |
| * and/or other materials provided with the distribution. |
| * 3. The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
| * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
| * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR |
| * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
| * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| // Borrowed from Chromium's src/base/numerics/safe_conversions.h. |
| |
| #ifndef TALK_BASE_SAFE_CONVERSIONS_H_ |
| #define TALK_BASE_SAFE_CONVERSIONS_H_ |
| |
| #include <limits> |
| |
| #include "talk/base/common.h" |
| #include "talk/base/logging.h" |
| #include "talk/base/safe_conversions_impl.h" |
| |
| namespace talk_base { |
| |
| inline void Check(bool condition) { |
| if (!condition) { |
| LOG(LS_ERROR) << "CHECK failed."; |
| Break(); |
| // The program should have crashed at this point. |
| } |
| } |
| |
| // 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::RangeCheck<Dst>(value) == internal::TYPE_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::RangeCheck<Dst>(value)) { |
| case internal::TYPE_VALID: |
| return static_cast<Dst>(value); |
| |
| case internal::TYPE_UNDERFLOW: |
| return std::numeric_limits<Dst>::min(); |
| |
| case internal::TYPE_OVERFLOW: |
| return std::numeric_limits<Dst>::max(); |
| |
| // Should fail only on attempting to assign NaN to a saturated integer. |
| case internal::TYPE_INVALID: |
| Check(false); |
| return std::numeric_limits<Dst>::max(); |
| } |
| |
| Check(false); // NOTREACHED(); |
| return static_cast<Dst>(value); |
| } |
| |
| } // namespace talk_base |
| |
| #endif // TALK_BASE_SAFE_CONVERSIONS_H_ |