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
15 // clang-format off
16 #include "pw_rpc/internal/log_config.h" // PW_LOG_* macros must be first.
17
18 #include "pw_rpc/client.h"
19 // clang-format on
20
21 #include "pw_log/log.h"
22 #include "pw_rpc/internal/client_call.h"
23 #include "pw_rpc/internal/packet.h"
24 #include "pw_status/try.h"
25
26 namespace pw::rpc {
27 namespace {
28
29 using internal::Packet;
30 using internal::pwpb::PacketType;
31
32 } // namespace
33
ProcessPacket(ConstByteSpan data)34 Status Client::ProcessPacket(ConstByteSpan data) {
35 PW_TRY_ASSIGN(Packet packet, Endpoint::ProcessPacket(data, Packet::kClient));
36
37 // Find an existing call for this RPC, if any.
38 internal::rpc_lock().lock();
39 IntrusiveList<internal::Call>::iterator call = FindCall(packet);
40
41 internal::Channel* channel = GetInternalChannel(packet.channel_id());
42
43 if (channel == nullptr) {
44 internal::rpc_lock().unlock();
45 PW_LOG_WARN("RPC client received a packet for an unregistered channel: %lu",
46 static_cast<unsigned long>(packet.channel_id()));
47 return Status::Unavailable();
48 }
49
50 if (call == calls_end()) {
51 // The call for the packet does not exist. If the packet is a server stream
52 // message, notify the server so that it can kill the stream. Otherwise,
53 // silently drop the packet (as it would terminate the RPC anyway).
54 if (packet.type() == PacketType::SERVER_STREAM) {
55 channel->Send(Packet::ClientError(packet, Status::FailedPrecondition()))
56 .IgnoreError();
57 PW_LOG_WARN("RPC client received stream message for an unknown call");
58 }
59 internal::rpc_lock().unlock();
60 return OkStatus(); // OK since the packet was handled
61 }
62
63 switch (packet.type()) {
64 case PacketType::RESPONSE:
65 // RPCs without a server stream include a payload with the final packet.
66 if (call->has_server_stream()) {
67 static_cast<internal::StreamResponseClientCall&>(*call).HandleCompleted(
68 packet.status());
69 } else {
70 static_cast<internal::UnaryResponseClientCall&>(*call).HandleCompleted(
71 packet.payload(), packet.status());
72 }
73 break;
74 case PacketType::SERVER_ERROR:
75 call->HandleError(packet.status());
76 break;
77 case PacketType::SERVER_STREAM:
78 if (call->has_server_stream()) {
79 call->HandlePayload(packet.payload());
80 } else {
81 // Report the error to the server so it can abort the RPC.
82 channel->Send(Packet::ClientError(packet, Status::InvalidArgument()))
83 .IgnoreError(); // Errors are logged in Channel::Send.
84 call->HandleError(Status::InvalidArgument());
85 PW_LOG_DEBUG("Received SERVER_STREAM for RPC without a server stream");
86 }
87 break;
88
89 case PacketType::REQUEST:
90 case PacketType::CLIENT_STREAM:
91 case PacketType::CLIENT_ERROR:
92 case PacketType::CLIENT_REQUEST_COMPLETION:
93 default:
94 internal::rpc_lock().unlock();
95 PW_LOG_WARN("pw_rpc client unable to handle packet of type %u",
96 static_cast<unsigned>(packet.type()));
97 }
98
99 return OkStatus(); // OK since the packet was handled
100 }
101
102 } // namespace pw::rpc
103