blob: 743f995b11c50b79329af8ac273eb3a56a8ee028 [file] [log] [blame]
// Copyright 2020 The Pigweed Authors
// Licensed 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
// 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.
// clang-format off
#include "pw_rpc/internal/log_config.h" // PW_LOG_* macros must be first.
#include "pw_rpc/nanopb/internal/common.h"
// clang-format on
#include "pb_decode.h"
#include "pb_encode.h"
#include "pw_assert/check.h"
#include "pw_log/log.h"
#include "pw_result/result.h"
#include "pw_rpc/internal/client_call.h"
#include "pw_rpc/nanopb/server_reader_writer.h"
#include "pw_status/try.h"
namespace pw::rpc::internal {
namespace {
// Nanopb 3 uses pb_field_s and Nanopb 4 uses pb_msgdesc_s for fields. The
// Nanopb version macro is difficult to use, so deduce the correct type from the
// pb_decode function.
template <typename DecodeFunction>
struct NanopbTraits;
template <typename FieldsType>
struct NanopbTraits<bool(pb_istream_t*, FieldsType, void*)> {
using Fields = FieldsType;
using Fields = typename NanopbTraits<decltype(pb_decode)>::Fields;
Result<ByteSpan> EncodeToPayloadBuffer(Call& call,
const void* payload,
NanopbSerde serde)
PW_UNLOCK_FUNCTION(rpc_lock()) {
std::span<std::byte> payload_buffer = call.PayloadBufferInternal();
StatusWithSize result = serde.Encode(payload, payload_buffer);
if (!result.ok()) {
return result.status();
return payload_buffer.first(result.size());
} // namespace
// PB_NO_ERRMSG is used in pb_decode.h and pb_encode.h to enable or disable the
// errmsg member of the istream and ostream structs. If errmsg is available, use
// it to give more detailed log messages.
#define PW_RPC_LOG_NANOPB_FAILURE(msg, stream) PW_LOG_ERROR(msg)
#define PW_RPC_LOG_NANOPB_FAILURE(msg, stream) \
PW_LOG_ERROR(msg ": %s", stream.errmsg)
#endif // PB_NO_ERRMSG
StatusWithSize NanopbSerde::Encode(const void* proto_struct,
ByteSpan buffer) const {
auto output = pb_ostream_from_buffer(
reinterpret_cast<pb_byte_t*>(, buffer.size());
if (!pb_encode(&output, static_cast<Fields>(fields_), proto_struct)) {
PW_RPC_LOG_NANOPB_FAILURE("Nanopb protobuf encode failed", output);
return StatusWithSize::Internal();
return StatusWithSize(output.bytes_written);
bool NanopbSerde::Decode(ConstByteSpan buffer, void* proto_struct) const {
auto input = pb_istream_from_buffer(
reinterpret_cast<const pb_byte_t*>(, buffer.size());
bool result = pb_decode(&input, static_cast<Fields>(fields_), proto_struct);
if (!result) {
PW_RPC_LOG_NANOPB_FAILURE("Nanopb protobuf decode failed", input);
return result;
void NanopbSendInitialRequest(ClientCall& call,
NanopbSerde serde,
const void* payload) {
Result<ByteSpan> result = EncodeToPayloadBuffer(call, payload, serde);
if (result.ok()) {
} else {
Status NanopbSendStream(Call& call, const void* payload, NanopbSerde serde) {
if (!call.active_locked()) {
return Status::FailedPrecondition();
Result<ByteSpan> result = EncodeToPayloadBuffer(call, payload, serde);
return call.Write(*result);
Status SendFinalResponse(NanopbServerCall& call,
const void* payload,
const Status status) {
if (!call.active_locked()) {
return Status::FailedPrecondition();
Result<ByteSpan> result =
EncodeToPayloadBuffer(call, payload, call.serde().response());
if (!result.ok()) {
return call.CloseAndSendServerError(Status::Internal());
return call.CloseAndSendResponse(*result, status);
} // namespace pw::rpc::internal