1 // Copyright 2021 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/internal/endpoint.h"
19 // clang-format on
20
21 #include "pw_log/log.h"
22 #include "pw_rpc/internal/lock.h"
23
24 namespace pw::rpc::internal {
25
rpc_lock()26 RpcLock& rpc_lock() {
27 static RpcLock lock;
28 return lock;
29 }
30
~Endpoint()31 Endpoint::~Endpoint() {
32 // Since the calls remove themselves from the Endpoint in
33 // CloseAndSendResponse(), close responders until no responders remain.
34 while (!calls_.empty()) {
35 calls_.front().CloseAndSendResponse(OkStatus()).IgnoreError();
36 }
37 }
38
ProcessPacket(std::span<const std::byte> data,Packet::Destination destination)39 Result<Packet> Endpoint::ProcessPacket(std::span<const std::byte> data,
40 Packet::Destination destination) {
41 Result<Packet> result = Packet::FromBuffer(data);
42
43 if (!result.ok()) {
44 PW_LOG_WARN("Failed to decode pw_rpc packet");
45 return Status::DataLoss();
46 }
47
48 Packet& packet = *result;
49
50 if (packet.channel_id() == Channel::kUnassignedChannelId ||
51 packet.service_id() == 0 || packet.method_id() == 0) {
52 PW_LOG_WARN("Received malformed pw_rpc packet");
53 return Status::DataLoss();
54 }
55
56 if (packet.destination() != destination) {
57 return Status::InvalidArgument();
58 }
59
60 return result;
61 }
62
RegisterCall(Call & call)63 void Endpoint::RegisterCall(Call& call) {
64 Call* const existing_call = FindCallById(
65 call.channel_id_locked(), call.service_id(), call.method_id());
66
67 RegisterUniqueCall(call);
68
69 if (existing_call != nullptr) {
70 // TODO(pwbug/597): Ensure call object is locked when calling callback. For
71 // on_error, could potentially move the callback and call it after the
72 // lock is released.
73 existing_call->HandleError(Status::Cancelled());
74 rpc_lock().lock();
75 }
76 }
77
FindCallById(uint32_t channel_id,uint32_t service_id,uint32_t method_id)78 Call* Endpoint::FindCallById(uint32_t channel_id,
79 uint32_t service_id,
80 uint32_t method_id) {
81 for (Call& call : calls_) {
82 if (channel_id == call.channel_id_locked() &&
83 service_id == call.service_id() && method_id == call.method_id()) {
84 return &call;
85 }
86 }
87 return nullptr;
88 }
89
CloseChannel(uint32_t channel_id)90 Status Endpoint::CloseChannel(uint32_t channel_id) {
91 LockGuard lock(rpc_lock());
92
93 Channel* channel = channels_.Get(channel_id);
94 if (channel == nullptr) {
95 return Status::NotFound();
96 }
97 channel->Close();
98
99 // Close pending calls on the channel that's going away.
100 auto previous = calls_.before_begin();
101 auto current = calls_.begin();
102
103 while (current != calls_.end()) {
104 if (channel_id == current->channel_id_locked()) {
105 current->HandleChannelClose();
106 current = calls_.erase_after(previous); // previous stays the same
107 } else {
108 previous = current;
109 ++current;
110 }
111 }
112
113 return OkStatus();
114 }
115
116 } // namespace pw::rpc::internal
117