1 // Copyright 2023 The Pigweed Authors
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License"); you may not
4 // use this file except in compliance with the License. You may obtain a copy of
5 // the License at
6 //
7 //     https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
11 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
12 // License for the specific language governing permissions and limitations under
13 // the License.
14 
15 #pragma once
16 #include <cstddef>
17 
18 #include "pw_bluetooth_sapphire/internal/host/common/byte_buffer.h"
19 #include "pw_bluetooth_sapphire/internal/host/l2cap/l2cap_defs.h"
20 
21 namespace bt::l2cap {
22 
23 // Computes the Frame Check Sequence (FCS) over the bytes in |view| per Core
24 // Spec v5.0, Vol 3, Part A, Section 3.3.5. |initial_value| may be
25 // kInitialFcsValue to begin a new FCS computation or the result of FCS
26 // computation over a contiguous sequence immediately preceding |view|. If
27 // |view| has length zero, returns |initial_value|.
28 [[nodiscard]] FrameCheckSequence ComputeFcs(
29     BufferView view, FrameCheckSequence initial_value = kInitialFcsValue);
30 
31 }  // namespace bt::l2cap
32