1 /*
2  * Copyright (C) 2019 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 #include "host/frontend/webrtc/adb_handler.h"
18 
19 #include <unistd.h>
20 
21 #include <android-base/logging.h>
22 
23 using namespace android;
24 
25 namespace cuttlefish {
26 namespace webrtc_streaming {
27 
28 namespace {
29 
SetupAdbSocket(const std::string & adb_host_and_port)30 SharedFD SetupAdbSocket(const std::string &adb_host_and_port) {
31   auto colonPos = adb_host_and_port.find(':');
32   if (colonPos == std::string::npos) {
33     return SharedFD();
34   }
35 
36   auto host = adb_host_and_port.substr(0, colonPos);
37 
38   const char *portString = adb_host_and_port.c_str() + colonPos + 1;
39   char *end;
40   unsigned long port = strtoul(portString, &end, 10);
41 
42   if (end == portString || *end != '\0' || port > 65535) {
43     return SharedFD();
44   }
45 
46   auto local_client = SharedFD::SocketLocalClient(port, SOCK_STREAM);
47   if (!local_client->IsOpen()) {
48     LOG(WARNING) << "Failed to connect to ADB server socket (non-Android guest?) Using /dev/null workaround."
49                  << local_client->StrError();
50     return SharedFD::Open("/dev/null", O_RDWR);
51   }
52   return local_client;
53 }
54 
55 }  // namespace
56 
AdbHandler(const std::string & adb_host_and_port,std::function<void (const uint8_t *,size_t)> send_to_client)57 AdbHandler::AdbHandler(
58     const std::string &adb_host_and_port,
59     std::function<void(const uint8_t *, size_t)> send_to_client)
60     : send_to_client_(send_to_client),
61       adb_socket_(SetupAdbSocket(adb_host_and_port)),
62       shutdown_(SharedFD::Event(0,0))
63 {
64     std::thread loop([this]() { ReadLoop(); });
65     read_thread_.swap(loop);
66 }
67 
68 
~AdbHandler()69 AdbHandler::~AdbHandler() {
70     // Send a message to the looper to shut down.
71     uint64_t v = 1;
72     shutdown_->Write(&v, sizeof(v));
73     // Shut down the socket as well.  Not srictly necessary.
74     adb_socket_->Shutdown(SHUT_RDWR);
75     read_thread_.join();
76 }
77 
ReadLoop()78 void AdbHandler::ReadLoop() {
79   while (1) {
80     uint8_t buffer[4096];
81 
82     read_set_.Set(shutdown_);
83     read_set_.Set(adb_socket_);
84     Select(&read_set_, nullptr, nullptr, nullptr);
85 
86     if (read_set_.IsSet(adb_socket_)) {
87         auto read = adb_socket_->Read(buffer, sizeof(buffer));
88         if (read < 0) {
89             LOG(ERROR) << "Error on reading from ADB socket: " << strerror(adb_socket_->GetErrno());
90             break;
91         }
92         if (read) {
93             send_to_client_(buffer, read);
94         }
95     }
96 
97     if (read_set_.IsSet(shutdown_)) {
98         LOG(INFO) << "AdbHandler is shutting down.";
99         break;
100     }
101   }
102 }
103 
handleMessage(const uint8_t * msg,size_t len)104 void AdbHandler::handleMessage(const uint8_t *msg, size_t len) {
105   size_t sent = 0;
106   while (sent < len) {
107     auto this_sent = adb_socket_->Write(&msg[sent], len - sent);
108     if (this_sent < 0) {
109       LOG(ERROR) << "Error writing to adb socket: " << adb_socket_->StrError();
110       return;
111     }
112     sent += this_sent;
113   }
114 }
115 
116 }  // namespace webrtc_streaming
117 }  // namespace cuttlefish
118