| /******************************************************************** |
| * 2014 - |
| * open source under Apache License Version 2.0 |
| ********************************************************************/ |
| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| #ifndef _HDFS_LIBHDFS3_COMMON_HWCHECKSUM_H_ |
| #define _HDFS_LIBHDFS3_COMMON_HWCHECKSUM_H_ |
| |
| #include "Checksum.h" |
| |
| namespace Hdfs { |
| namespace Internal { |
| |
| /** |
| * Calculate CRC with hardware support. |
| */ |
| class HWCrc32c: public Checksum { |
| public: |
| /** |
| * Constructor. |
| */ |
| HWCrc32c() : |
| crc(0xFFFFFFFF) { |
| } |
| |
| uint32_t getValue() { |
| return ~crc; |
| } |
| |
| /** |
| * @ref Checksum#reset() |
| */ |
| void reset() { |
| crc = 0xFFFFFFFF; |
| } |
| |
| /** |
| * @ref Checksum#update(const void *, int) |
| */ |
| void update(const void * b, int len); |
| |
| /** |
| * Destory an HWCrc32 instance. |
| */ |
| ~HWCrc32c() { |
| } |
| |
| /** |
| * To test if the hardware support this function. |
| * @return true if the hardware support to calculate the CRC. |
| */ |
| static bool available(); |
| |
| private: |
| void updateInt64(const char * b, int len); |
| |
| private: |
| uint32_t crc; |
| }; |
| |
| } |
| } |
| |
| #endif /* _HDFS_LIBHDFS3_COMMON_HWCHECKSUM_H_ */ |