1 /* 2 * Copyright (C) 2025 The Android Open Source Project 3 * 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 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 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. 15 */ 16 17 #pragma once 18 19 #include <condition_variable> 20 #include <deque> 21 #include <functional> 22 #include <future> 23 #include <mutex> 24 #include <optional> 25 #include <string_view> 26 #include <thread> 27 #include <variant> 28 #include <vector> 29 30 #include <android-base/unique_fd.h> 31 32 #include "AtResponse.h" 33 34 namespace aidl { 35 namespace android { 36 namespace hardware { 37 namespace radio { 38 namespace implementation { 39 using ::android::base::unique_fd; 40 41 struct AtChannel { 42 using HostChannelFactory = std::function<unique_fd()>; 43 44 struct RequestPipe { RequestPipeAtChannel::RequestPipe45 explicit RequestPipe(int fd) : mFd(fd) {} 46 47 bool operator()(std::string_view request) const; 48 49 RequestPipe(const RequestPipe&) = default; 50 RequestPipe& operator=(const RequestPipe&) = default; 51 52 private: 53 int mFd; 54 }; 55 56 struct Conversation { 57 using FilterFunc = std::function<bool(const AtResponse&)>; 58 using Duration = std::chrono::steady_clock::duration; 59 60 AtResponsePtr operator()(RequestPipe, std::string_view request, 61 const FilterFunc& filter, Duration timeout); 62 AtResponsePtr operator()(RequestPipe, std::string_view request, 63 const FilterFunc& filter); 64 65 bool send(const AtResponsePtr& response); 66 67 private: 68 const FilterFunc* mFilter = nullptr; 69 std::promise<AtResponsePtr> mSink; 70 mutable std::mutex mMtx; 71 }; 72 73 using InitSequence = std::function<bool(RequestPipe, Conversation&)>; 74 using Requester = std::function<bool(RequestPipe)>; 75 using ResponseSink = std::function<bool(const AtResponsePtr&)>; 76 77 AtChannel(HostChannelFactory hostChannelFactory, 78 InitSequence initSequence); 79 ~AtChannel(); 80 81 void queueRequester(Requester); 82 void addResponseSink(ResponseSink); 83 84 private: 85 void requestLoop(); 86 void readingLoop(int fd); 87 Requester getRequester(); 88 void broadcastResponse(const AtResponsePtr&); 89 90 RequestPipe getHostChannelPipe(); 91 bool receiveResponses(int hostChannel, std::vector<char>* unconsumed); 92 bool receiveResponsesImpl(const char* begin, const char* end, 93 std::vector<char>* unconsumed); 94 const char* receiveOneResponse(const char* begin, const char* end); 95 96 const HostChannelFactory mHostChannelFactory; 97 const InitSequence mInitSequence; 98 Conversation mConversation; 99 unique_fd mHostChannel; 100 std::deque<Requester> mRequesterQueue; 101 std::condition_variable mRequesterAvailable; 102 std::vector<ResponseSink> mResponseSinks; 103 std::vector<char> mResponseBuf; 104 std::thread mRequestThread; 105 std::thread mReaderThread; 106 mutable std::mutex mRequestQueueMtx; 107 mutable std::mutex mResponseSinksMtx; 108 }; 109 110 } // namespace implementation 111 } // namespace radio 112 } // namespace hardware 113 } // namespace android 114 } // namespace aidl 115