Allow client to specify keepalive interval.

app/src/main/java/org/briarproject/snooze/Constants.java

@@ -21,4 +21,6 @@ interface Constants {
 	int CONNECT_TIMEOUT_MS = 30 * 1000;
 
 	int RECONNECT_DELAY_MS = 10 * 1000;
+
+	int KEEPALIVE_INTERVAL_MS = 60 * 1000;
 }

app/src/main/java/org/briarproject/snooze/NetworkThread.java → app/src/main/java/org/briarproject/snooze/NetworkClient.java

@@ -3,8 +3,10 @@ package org.briarproject.snooze;
 import android.content.Context;
 import android.os.PowerManager;
 
+import java.io.DataOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.OutputStream;
 import java.net.InetSocketAddress;
 import java.net.Socket;
 
@@ -14,21 +16,22 @@ import static org.briarproject.snooze.Constants.CONNECT_TIMEOUT_MS;
 import static org.briarproject.snooze.Constants.RECONNECT_DELAY_MS;
 import static org.briarproject.snooze.Constants.SOCKET_TIMEOUT_MS;
 
-class NetworkThread extends Thread {
+class NetworkClient extends Thread {
 
-	private static final String TAG = NetworkThread.class.getName();
+	private static final String LOCK_TAG = NetworkClient.class.getName();
 
 	private final String host;
-	private final int port;
+	private final int port, keepaliveIntervalSecs;
 	private final Logger log;
 	private final PowerManager.WakeLock wakeLock;
 
-	NetworkThread(String host, int port, Context appContext) {
+	NetworkClient(String host, int port, int keepaliveIntervalMs, Context appContext) {
 		this.host = host;
 		this.port = port;
+		keepaliveIntervalSecs = (keepaliveIntervalMs / 1000) & 0xffff;
 		log = ((SnoozeApplication) appContext).getLogger();
 		PowerManager pm = (PowerManager) appContext.getSystemService(POWER_SERVICE);
-		wakeLock = pm.newWakeLock(PARTIAL_WAKE_LOCK, TAG);
+		wakeLock = pm.newWakeLock(PARTIAL_WAKE_LOCK, LOCK_TAG);
 		wakeLock.setReferenceCounted(false);
 		setDaemon(true);
 	}
@@ -42,8 +45,11 @@ class NetworkThread extends Thread {
 				s.setSoTimeout(SOCKET_TIMEOUT_MS);
 				log.log("Connecting to " + host + ":" + port);
 				s.connect(new InetSocketAddress(host, port), CONNECT_TIMEOUT_MS);
+				DataOutputStream out = new DataOutputStream(s.getOutputStream());
 				InputStream in = s.getInputStream();
 				log.log("Connected");
+				out.writeShort(keepaliveIntervalSecs);
+				out.flush();
 				for (int read = 0; read != -1 && !isInterrupted(); read = in.read(buf)) {
 					wakeLock.acquire();
 					log.log("Read " + read + " bytes");
@@ -58,7 +64,7 @@ class NetworkThread extends Thread {
 					tryToClose(s);
 				}
 			} catch (IOException e) {
-				log.log("Network error: " + e.toString());
+				log.log("Network error: " + e);
 				tryToClose(s);
 			}
 			try {

app/src/main/java/org/briarproject/snooze/SnoozeService.java

@@ -22,10 +22,11 @@ import static org.briarproject.snooze.Constants.EXTRA_ALARM_TYPE;
 import static org.briarproject.snooze.Constants.EXTRA_FOREGROUND_SERVICE;
 import static org.briarproject.snooze.Constants.EXTRA_WAKE_LOCK;
 import static org.briarproject.snooze.Constants.EXTRA_WIFI_LOCK;
+import static org.briarproject.snooze.Constants.KEEPALIVE_INTERVAL_MS;
 
 public class SnoozeService extends Service {
 
-	private static final String TAG = SnoozeService.class.getName();
+	private static final String LOCK_TAG = SnoozeService.class.getName();
 
 	private final Binder binder = new Binder();
 	private final PowerManagementEventReceiver receiver = new PowerManagementEventReceiver();
@@ -33,7 +34,7 @@ public class SnoozeService extends Service {
 	private boolean foreground = false;
 	private PowerManager.WakeLock wakeLock = null;
 	private WifiManager.WifiLock wifiLock = null;
-	private NetworkThread networkThread = null;
+	private NetworkClient networkClient = null;
 	private Alarm alarm = null;
 
 	private volatile Logger log = null;
@@ -123,7 +124,7 @@ public class SnoozeService extends Service {
 		if (wakeLock != null) throw new IllegalStateException();
 		log.log("Acquiring wake lock");
 		PowerManager pm = (PowerManager) getSystemService(POWER_SERVICE);
-		wakeLock = pm.newWakeLock(PARTIAL_WAKE_LOCK, TAG);
+		wakeLock = pm.newWakeLock(PARTIAL_WAKE_LOCK, LOCK_TAG);
 		wakeLock.setReferenceCounted(false);
 		wakeLock.acquire();
 	}
@@ -139,7 +140,7 @@ public class SnoozeService extends Service {
 		if (wifiLock != null) throw new IllegalStateException();
 		log.log("Acquiring wifi lock");
 		WifiManager wm = (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);
-		wifiLock = wm.createWifiLock(WIFI_MODE_FULL, TAG);
+		wifiLock = wm.createWifiLock(WIFI_MODE_FULL, LOCK_TAG);
 		wifiLock.setReferenceCounted(false);
 		wifiLock.acquire();
 	}
@@ -152,11 +153,12 @@ public class SnoozeService extends Service {
 	}
 
 	private void startNetworkThread() {
-		if (networkThread != null) networkThread.interrupt();
+		if (networkClient != null) networkClient.interrupt();
 		String host = getString(R.string.host);
 		int port = getResources().getInteger(R.integer.port);
-		networkThread = new NetworkThread(host, port, getApplicationContext());
-		networkThread.start();
+		networkClient = new NetworkClient(host, port, KEEPALIVE_INTERVAL_MS,
+				getApplicationContext());
+		networkClient.start();
 	}
 
 	private void setAlarm(AlarmType alarmType) {

server/src/main/java/org/briarproject/snooze/SnoozeServer.java

 package org.briarproject.snooze;
 
+import java.io.DataInputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.net.ServerSocket;
@@ -7,30 +8,27 @@ import java.net.Socket;
 
 public class SnoozeServer implements Runnable {
 
-	private static final int SOCKET_TIMEOUT_MS = 5 * 60 * 1000;
+	private static final int SOCKET_TIMEOUT_MS = 2 * 60 * 1000;
 
-	private final int port, writeIntervalMs;
+	private final int port;
 
-	public SnoozeServer(int port, int writeIntervalMs) {
+	public SnoozeServer(int port) {
 		this.port = port;
-		this.writeIntervalMs = writeIntervalMs;
 	}
 
 	public static void main(String[] args) {
-		if (args.length != 2) printUsageAndExit();
+		if (args.length != 1) printUsageAndExit();
 		try {
 			int port = Integer.parseInt(args[0]);
 			if (port < 1 || port > 65535) printUsageAndExit();
-			int writeIntervalMs = Integer.parseInt(args[1]);
-			if (writeIntervalMs < 1) printUsageAndExit();
-			new SnoozeServer(port, writeIntervalMs).run();
+			new SnoozeServer(port).run();
 		} catch (NumberFormatException e) {
 			printUsageAndExit();
 		}
 	}
 
 	private static void printUsageAndExit() {
-		System.err.println("Usage: SnoozeServer <port> <write_interval_ms>");
+		System.err.println("Usage: SnoozeServer <port>");
 		System.exit(1);
 	}
 
@@ -39,7 +37,7 @@ public class SnoozeServer implements Runnable {
 		try {
 			ServerSocket ss = new ServerSocket(port);
 			System.out.println("Listening: " + ss.getLocalSocketAddress());
-			while (true) new WriterThread(ss.accept(), writeIntervalMs).start();
+			while (true) new WriterThread(ss.accept()).start();
 		} catch (IOException e) {
 			System.err.println(e.toString());
 		}
@@ -48,11 +46,9 @@ public class SnoozeServer implements Runnable {
 	private static class WriterThread extends Thread {
 
 		private final Socket socket;
-		private final int writeIntervalMs;
 
-		private WriterThread(Socket socket, int writeIntervalMs) {
+		private WriterThread(Socket socket) {
 			this.socket = socket;
-			this.writeIntervalMs = writeIntervalMs;
 			setDaemon(true);
 		}
 
@@ -60,11 +56,13 @@ public class SnoozeServer implements Runnable {
 		public void run() {
 			try {
 				socket.setSoTimeout(SOCKET_TIMEOUT_MS);
+				DataInputStream in = new DataInputStream(socket.getInputStream());
 				OutputStream out = socket.getOutputStream();
+				int keepaliveIntervalSecs = in.readUnsignedShort();
 				while (!socket.isClosed()) {
 					System.out.println("Writing: " + socket.getRemoteSocketAddress());
 					out.write(0);
-					sleep(writeIntervalMs);
+					sleep(keepaliveIntervalSecs * 1000);
 				}
 				System.out.println("Socket closed: " + socket.getRemoteSocketAddress());
 			} catch (IOException | InterruptedException e) {