2 * Copyright 2016 Facebook, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
19 namespace folly { namespace detail {
22 * Compute a CRC-32C checksum of a buffer using a hardware-accelerated
25 * @note This function is exposed to support special cases where the
26 * calling code is absolutely certain it ought to invoke a hardware-
27 * accelerated CRC-32C implementation - unit tests, for example. For
28 * all other scenarios, please call crc32c() and let it pick an
29 * implementation based on the capabilities of the underlying CPU.
31 uint32_t crc32c_hw(const uint8_t* data, size_t nbytes,
32 uint32_t startingChecksum = ~0U);
35 * Check whether a hardware-accelerated CRC-32C implementation is
36 * supported on the current CPU.
38 bool crc32c_hw_supported();
41 * Compute a CRC-32C checksum of a buffer using a portable,
42 * software-only implementation.
44 * @note This function is exposed to support special cases where the
45 * calling code is absolutely certain it wants to use the software
46 * implementation instead of the hardware-accelerated code - unit
47 * tests, for example. For all other scenarios, please call crc32c()
48 * and let it pick an implementation based on the capabilities of
51 uint32_t crc32c_sw(const uint8_t* data, size_t nbytes,
52 uint32_t startingChecksum = ~0U);