2 * Copyright 2015 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.
18 #include <folly/wangle/codec/ByteToMessageCodec.h>
20 namespace folly {namespace wangle {
23 * A decoder that splits the received IOBufs by the fixed number
24 * of bytes. For example, if you received the following four
27 * +---+----+------+----+
28 * | A | BC | DEFG | HI |
29 * +---+----+------+----+
31 * A FixedLengthFrameDecoder will decode them into the following three
32 * packets with the fixed length:
39 class FixedLengthFrameDecoder
40 : public ByteToMessageCodec {
43 FixedLengthFrameDecoder(size_t length)
46 std::unique_ptr<IOBuf> decode(Context* ctx, IOBufQueue& q, size_t& needed) {
47 if (q.chainLength() < length_) {
48 needed = length_ - q.chainLength();
52 return q.split(length_);