源碼
Git clone https://github.com/barry-ran/QtScrcpy.git
Server端
入口檔案 src/main/java/com/genymobile/scrcpy/Server.java
入口main函數
public static void main(String... args) throws Exception {
//用來捕捉整個程式的異常
Thread.setDefaultUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {
@Override
public void uncaughtException(Thread t, Throwable e) {
Ln.e("Exception on thread " + t, e);
suggestFix(e);
}
});
Options options = createOptions(args); //解析參數配置，總共有14個參數
Ln.initLogLevel(options.getLogLevel());
scrcpy(options); //下一步
}
下一步scrcpy函數
private static void scrcpy(Options options) throws IOException {
……
final Device device = new Device(options);
try (DesktopConnection connection = DesktopConnection.open(device, tunnelForward)) { //建立socket連接配接
ScreenEncoder screenEncoder = new ScreenEncoder(options.getSendFrameMeta(), options.getBitRate(), options.getMaxFps(), codecOptions); //螢幕編碼
if (options.getControl()) {
final Controller controller = new Controller(device, connection);
// asynchronous
startController(controller); //指令流監聽并做處理，使用的線程，内部死循環監聽處理
startDeviceMessageSender(controller.getSender()); //監聽剪切闆事件
device.setClipboardListener(new Device.ClipboardListener() {
@Override
public void onClipboardTextChanged(String text) {
controller.getSender().pushClipboardText(text);
}
});
}
try {
// synchronous
screenEncoder.streamScreen(device, connection.getVideoFd()); //視訊流編碼
} catch (IOException e) {
// this is expected on close
Ln.d("Screen streaming stopped");
}
}
}
建立localsocket，視訊流和指令流同屬一個socket
public static DesktopConnection open(Device device, boolean tunnelForward) throws IOException {
LocalSocket videoSocket;
LocalSocket controlSocket;
if (tunnelForward) {
LocalServerSocket localServerSocket = new LocalServerSocket(SOCKET_NAME);
try {
videoSocket = localServerSocket.accept(); //建立socket并處于阻塞狀态
// send one byte so the client may read() to detect a connection error
videoSocket.getOutputStream().write(0); //發送一個位元組資料，用戶端第一次連上接收到的資料
try {
controlSocket = localServerSocket.accept();
} catch (IOException | RuntimeException e) {
videoSocket.close();
throw e;
}
} finally {
localServerSocket.close();
}
} else {
videoSocket = connect(SOCKET_NAME); //視訊流socket
try {
controlSocket = connect(SOCKET_NAME); //控制指令socket
} catch (IOException | RuntimeException e) {
videoSocket.close();
throw e;
}
}
DesktopConnection connection = new DesktopConnection(videoSocket, controlSocket);
Size videoSize = device.getScreenInfo().getVideoSize();
//往視訊流socket上發送裝置名，寬度，高度
connection.send(Device.getDeviceName(), videoSize.getWidth(), videoSize.getHeight());
return connection;
}
開啟指令流監聽
private static void startController(final Controller controller) {
new Thread(new Runnable() {
@Override
public void run() {
try {
controller.control(); //control()函數
} catch (IOException e) {
// this is expected on close
Ln.d("Controller stopped");
}
}
}).start();
}
control()函數
public void control() throws IOException {
// on start, power on the device
if (!device.isScreenOn()) {
device.injectKeycode(KeyEvent.KEYCODE_POWER);
// dirty hack
// After POWER is injected, the device is powered on asynchronously.
// To turn the device screen off while mirroring, the client will send a message that
// would be handled before the device is actually powered on, so its effect would
// be "canceled" once the device is turned back on.
// Adding this delay prevents to handle the message before the device is actually
// powered on.
SystemClock.sleep(500);
}
//死循環來處理指令流事件
while (true) {
handleEvent();
}
}
事件類型處理
private void handleEvent() throws IOException {
ControlMessage msg = connection.receiveControlMessage(); //接收控制流消息
switch (msg.getType()) {
case ControlMessage.TYPE_INJECT_KEYCODE:
if (device.supportsInputEvents()) {
injectKeycode(msg.getAction(), msg.getKeycode(), msg.getMetaState());
}
break;
case ControlMessage.TYPE_INJECT_TEXT:
if (device.supportsInputEvents()) {
injectText(msg.getText());
}
break;
case ControlMessage.TYPE_INJECT_TOUCH_EVENT:
if (device.supportsInputEvents()) {
injectTouch(msg.getAction(), msg.getPointerId(), msg.getPosition(), msg.getPressure(), msg.getButtons());
}
break;
case ControlMessage.TYPE_INJECT_SCROLL_EVENT: //以螢幕滾動事件為例
if (device.supportsInputEvents()) {
injectScroll(msg.getPosition(), msg.getHScroll(), msg.getVScroll());
}
break;
case ControlMessage.TYPE_BACK_OR_SCREEN_ON:
if (device.supportsInputEvents()) {
pressBackOrTurnScreenOn();
}
break;
case ControlMessage.TYPE_EXPAND_NOTIFICATION_PANEL:
device.expandNotificationPanel();
break;
case ControlMessage.TYPE_COLLAPSE_NOTIFICATION_PANEL:
device.collapsePanels();
break;
case ControlMessage.TYPE_GET_CLIPBOARD:
String clipboardText = device.getClipboardText();
if (clipboardText != null) {
sender.pushClipboardText(clipboardText); //剪切闆事件
}
break;
case ControlMessage.TYPE_SET_CLIPBOARD:
boolean paste = (msg.getFlags() & ControlMessage.FLAGS_PASTE) != 0;
setClipboard(msg.getText(), paste);
break;
case ControlMessage.TYPE_SET_SCREEN_POWER_MODE:
if (device.supportsInputEvents()) {
int mode = msg.getAction();
boolean setPowerModeOk = device.setScreenPowerMode(mode);
if (setPowerModeOk) {
Ln.i("Device screen turned " + (mode == Device.POWER_MODE_OFF ? "off" : "on"));
}
}
break;
case ControlMessage.TYPE_ROTATE_DEVICE:
device.rotateDevice();
break;
default:
// do nothing
}
}
接收控制流消息
public ControlMessage receiveControlMessage() throws IOException {
ControlMessage msg = reader.next();
while (msg == null) {
reader.readFrom(controlInputStream); //向控制流的輸入通道内讀取資料
msg = reader.next(); //循環讀取
}
return msg;
}
以螢幕滾動事件為例
private boolean injectScroll(Position position, int hScroll, int vScroll) {
long now = SystemClock.uptimeMillis();
Point point = device.getPhysicalPoint(position);
if (point == null) {
// ignore event
return false;
}
MotionEvent.PointerProperties props = pointerProperties[0];
props.id = 0;
MotionEvent.PointerCoords coords = pointerCoords[0];
coords.x = point.getX();
coords.y = point.getY();
coords.setAxisValue(MotionEvent.AXIS_HSCROLL, hScroll);
coords.setAxisValue(MotionEvent.AXIS_VSCROLL, vScroll);
//事件類型為ACTION_SCROLL
MotionEvent event = MotionEvent
.obtain(lastTouchDown, now, MotionEvent.ACTION_SCROLL, 1, pointerProperties, pointerCoords, 0, 0, 1f, 1f, DEVICE_ID_VIRTUAL, 0,
InputDevice.SOURCE_TOUCHSCREEN, 0);
return device.injectEvent(event); //事件注入機制
}
事件注入機制
public boolean injectEvent(InputEvent inputEvent, int mode) {
if (!supportsInputEvents()) {
throw new AssertionError("Could not inject input event if !supportsInputEvents()");
}
if (displayId != 0 && !InputManager.setDisplayId(inputEvent, displayId)) {
return false;
}
return serviceManager.getInputManager().injectInputEvent(inputEvent, mode);
}
使用了安卓核心的事件注入機制；
到此，控制流server端分析完
private Method getInjectInputEventMethod() throws NoSuchMethodException {
if (injectInputEventMethod == null) {
injectInputEventMethod = manager.getClass().getMethod("injectInputEvent", InputEvent.class, int.class);
}
return injectInputEventMethod;
}
監聽剪切闆事件
private static void startDeviceMessageSender(final DeviceMessageSender sender) {
new Thread(new Runnable() {
@Override
public void run() {
try {
sender.loop();
} catch (IOException | InterruptedException e) {
// this is expected on close
Ln.d("Device message sender stopped");
}
}
}).start();
}
循環監聽
public void loop() throws IOException, InterruptedException {
while (true) {
String text;
synchronized (this) {
while (clipboardText == null) {
wait();
}
text = clipboardText;
clipboardText = null;
}
DeviceMessage event = DeviceMessage.createClipboard(text); //安卓剪切闆事件
connection.sendDeviceMessage(event);
}
}
視訊流相關邏輯
視訊流編碼
public void streamScreen(Device device, FileDescriptor fd) throws IOException {
Workarounds.prepareMainLooper();
try {
internalStreamScreen(device, fd);
} catch (NullPointerException e) {
// Retry with workarounds enabled:
// <https://github.com/Genymobile/scrcpy/issues/365>
// <https://github.com/Genymobile/scrcpy/issues/940>
Ln.d("Applying workarounds to avoid NullPointerException");
Workarounds.fillAppInfo();
internalStreamScreen(device, fd);
}
}
private void internalStreamScreen(Device device, FileDescriptor fd) throws IOException {
MediaFormat format = createFormat(bitRate, maxFps, codecOptions);
device.setRotationListener(this);
boolean alive;
try {
do {
MediaCodec codec = createCodec(); //建立編碼器-h264 MediaFormat.MIMETYPE_VIDEO_AVC
IBinder display = createDisplay();
ScreenInfo screenInfo = device.getScreenInfo();
Rect contentRect = screenInfo.getContentRect();
// include the locked video orientation
Rect videoRect = screenInfo.getVideoSize().toRect();
// does not include the locked video orientation
Rect unlockedVideoRect = screenInfo.getUnlockedVideoSize().toRect();
int videoRotation = screenInfo.getVideoRotation();
int layerStack = device.getLayerStack();
setSize(format, videoRect.width(), videoRect.height());
configure(codec, format); //配置編碼器，包括碼流，fps，I幀時間間隔等
Surface surface = codec.createInputSurface(); //建立輸入緩沖區
setDisplaySurface(display, surface, videoRotation, contentRect, unlockedVideoRect, layerStack);
codec.start();
try {
alive = encode(codec, fd); //螢幕編碼
// do not call stop() on exception, it would trigger an IllegalStateException
codec.stop();
} finally {
destroyDisplay(display);
codec.release();
surface.release();
}
} while (alive);
} finally {
device.setRotationListener(null);
}
}
螢幕編碼
private boolean encode(MediaCodec codec, FileDescriptor fd) throws IOException {
boolean eof = false;
MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo(); //編碼緩沖區
while (!consumeRotationChange() && !eof) {
int outputBufferId = codec.dequeueOutputBuffer(bufferInfo, -1); //擷取輸出區的緩沖的索引
eof = (bufferInfo.flags & MediaCodec.BUFFER_FLAG_END_OF_STREAM) != 0;
try {
if (consumeRotationChange()) {
// must restart encoding with new size
break;
}
if (outputBufferId >= 0) {
ByteBuffer codecBuffer = codec.getOutputBuffer(outputBufferId); //根據索引擷取資料
if (sendFrameMeta) {
writeFrameMeta(fd, bufferInfo, codecBuffer.remaining()); //先将幀中繼資料資訊發送
}
IO.writeFully(fd, codecBuffer); //對外發送編碼後的幀資料
}
} finally {
if (outputBufferId >= 0) {
codec.releaseOutputBuffer(outputBufferId, false); //根據索引釋放緩沖區
}
}
}
return !eof;
}
![Android 雲遊戲實作[圖]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)