1 /*
2  * Copyright (c) 2023 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://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,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #include <atomic>
17 #include <thread>
18 #include "CommandLineInterface.h"
19 #include "PreviewerEngineLog.h"
20 #include "WebSocketServer.h"
21 
22 lws* WebSocketServer::webSocket = nullptr;
23 std::atomic<bool> WebSocketServer::interrupted = false;
24 WebSocketServer::WebSocketState WebSocketServer::webSocketWritable = WebSocketState::INIT;
25 uint8_t* WebSocketServer::firstImageBuffer = nullptr;
26 uint64_t WebSocketServer::firstImagebufferSize = 0;
27 
WebSocketServer()28 WebSocketServer::WebSocketServer() : serverThread(nullptr), serverPort(0)
29 {
30     protocols[0] = {"ws", WebSocketServer::ProtocolCallback, 0, MAX_PAYLOAD_SIZE};
31     protocols[1] = {NULL, NULL, 0, 0};
32 }
33 
~WebSocketServer()34 WebSocketServer::~WebSocketServer() {}
35 
GetInstance()36 WebSocketServer& WebSocketServer::GetInstance()
37 {
38     static WebSocketServer server;
39     return server;
40 }
41 
SetServerPort(int port)42 void WebSocketServer::SetServerPort(int port)
43 {
44     serverPort = port;
45 }
46 
ProtocolCallback(struct lws* wsi, enum lws_callback_reasons reason, void* user, void* in, size_t len)47 int WebSocketServer::ProtocolCallback(struct lws* wsi,
48                                       enum lws_callback_reasons reason,
49                                       void* user,
50                                       void* in,
51                                       size_t len)
52 {
53     switch (reason) {
54         case LWS_CALLBACK_PROTOCOL_INIT:
55             ILOG("Engine Websocket protocol init");
56             break;
57         case LWS_CALLBACK_ESTABLISHED:
58             ILOG("Websocket client connect");
59             webSocket = wsi;
60             lws_callback_on_writable(wsi);
61             break;
62         case LWS_CALLBACK_RECEIVE:
63             break;
64         case LWS_CALLBACK_SERVER_WRITEABLE:
65             ILOG("Engine websocket server writeable");
66             if (firstImagebufferSize > 0 && webSocketWritable == WebSocketState::UNWRITEABLE) {
67                 ILOG("Send last image after websocket reconnected");
68                 std::lock_guard<std::mutex> guard(WebSocketServer::GetInstance().mutex);
69                 lws_write(wsi,
70                           firstImageBuffer + LWS_PRE,
71                           firstImagebufferSize,
72                           LWS_WRITE_BINARY);
73             }
74             webSocketWritable = WebSocketState::WRITEABLE;
75             break;
76         case LWS_CALLBACK_CLOSED:
77             ILOG("Websocket client connection closed");
78             webSocketWritable = WebSocketState::UNWRITEABLE;
79             break;
80         default:
81             break;
82     }
83     return 0;
84 }
85 
SignalHandler(int sig)86 void WebSocketServer::SignalHandler(int sig)
87 {
88     interrupted = true;
89 }
90 
StartWebsocketListening()91 void WebSocketServer::StartWebsocketListening()
92 {
93     const auto sig = signal(SIGINT, SignalHandler);
94     if (sig == SIG_ERR) {
95         ELOG("StartWebsocketListening failed");
96         return;
97     }
98     ILOG("Begin to start websocket listening!");
99     struct lws_context_creation_info contextInfo = {0};
100     contextInfo.port = serverPort;
101     contextInfo.iface = serverHostname;
102     contextInfo.protocols = protocols;
103     contextInfo.ip_limit_wsi = websocketMaxConn;
104     contextInfo.options  = LWS_SERVER_OPTION_VALIDATE_UTF8;
105     struct lws_context* context = lws_create_context(&contextInfo);
106     if (context == nullptr) {
107         ELOG("WebSocketServer::StartWebsocketListening context memory allocation failed");
108         return;
109     }
110     while (!interrupted) {
111         if (lws_service(context, WEBSOCKET_SERVER_TIMEOUT)) {
112             interrupted = true;
113         }
114     }
115     lws_context_destroy(context);
116 }
117 
Run()118 void WebSocketServer::Run()
119 {
120     serverThread = std::make_unique<std::thread>([this]() {
121         this->StartWebsocketListening();
122     });
123     if (serverThread == nullptr) {
124         ELOG("WebSocketServer::Start serverThread memory allocation failed");
125     }
126     serverThread->detach();
127 }
128 
WriteData(unsigned char* data, size_t length)129 size_t WebSocketServer::WriteData(unsigned char* data, size_t length)
130 {
131     while (webSocketWritable != WebSocketState::WRITEABLE) {
132         std::this_thread::sleep_for(std::chrono::milliseconds(1));
133     }
134     if (webSocket != nullptr && webSocketWritable == WebSocketState::WRITEABLE) {
135         return lws_write(webSocket, data, length, LWS_WRITE_BINARY);
136     }
137     return 0;
138 }
139