1 // Copyright 2020 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 #pragma once 15 16 #include <array> 17 #include <span> 18 19 #include "pw_assert/assert.h" 20 #include "pw_hdlc/encoder.h" 21 #include "pw_rpc/channel.h" 22 #include "pw_stream/stream.h" 23 24 namespace pw::hdlc { 25 26 // Custom HDLC ChannelOutput class to write and read data through serial using 27 // the HDLC protocol. 28 // 29 // WARNING: This ChannelOutput is not thread-safe. If thread-safety is required, 30 // create a similar class that adds a mtuex to Send. 31 class RpcChannelOutput : public rpc::ChannelOutput { 32 public: 33 // The RpcChannelOutput class does not own the buffer it uses to store the 34 // protobuf bytes. This buffer is specified at the time of creation along with 35 // a writer object to which will be used to write and send the bytes. RpcChannelOutput(stream::Writer & writer,uint64_t address,const char * channel_name)36 constexpr RpcChannelOutput(stream::Writer& writer, 37 uint64_t address, 38 const char* channel_name) 39 : ChannelOutput(channel_name), writer_(writer), address_(address) {} 40 Send(std::span<const std::byte> buffer)41 Status Send(std::span<const std::byte> buffer) override { 42 return hdlc::WriteUIFrame(address_, buffer, writer_); 43 } 44 45 private: 46 stream::Writer& writer_; 47 const uint64_t address_; 48 }; 49 50 } // namespace pw::hdlc 51