RemoteDesktop: Switch connection direction and simplify client.

Instead of the server connecting back to a listening client, make it
into a more traditional setup with the server listening on a port and
the client connecting to it.

The client can now either connect directly, unencrypted and without the
ability to trigger listening and specifying a command, or through SSH,
as before with the possibilty to run a target application and causing
the creation of the listener.

With the direction change, there's only the need for one, local, port
forward with SSH, which simplifies things.

src/apps/remotedesktop/RemoteDesktop.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright 2009-2014, Haiku, Inc.
+ * Copyright 2009-2017, Haiku, Inc.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
@@ -25,16 +25,20 @@
 void
 print_usage(const char *app)
 {
-	printf("usage:\t%s --listenOnly [-p <listenPort>]\n", app);
+	printf("usage:\t%s <host> [-p <port>] [-w <width>] [-h <height>]\n", app);
-	printf("\t%s <user@host> [-p <listenPort>] [-s <sshPort>] [-c <command>]\n",
+	printf("usage:\t%s <user@host> -s [<sshPort>] [-p <port>] [-w <width>]"
-		app);
+		" [-h <height>] [-c <command>]\n", app);
 	printf("\t%s --help\n\n", app);
 
 	printf("Connect to & run applications from a different computer\n\n");
 	printf("Arguments available for use:\n\n");
-	printf("\t-p\t\tspecify the port to communicate on\n");
+	printf("\t-p\t\tspecify the port to communicate on (default 10900)\n");
-	printf("\t-c\t\tsend a command to the other computer\n");
+	printf("\t-c\t\tsend a command to the other computer (default Terminal)\n");
-	printf("\t-s\t\tuse ssh & specify the ssh port to communicate on\n");
+	printf("\t-s\t\tuse SSH, optionally specify the SSH port to use (22)\n");
+	printf("\t-w\t\tmake the virtual desktop use the specified width\n");
+	printf("\t-h\t\tmake the virtual desktop use the specified height\n");
+	printf("\nIf no width and height are specified, the window is opened with"
+		" the size of the the local screen.\n");
 }
 
 
@@ -46,14 +50,17 @@ main(int argc, char *argv[])
 		return 1;
 	}
 
-	bool listenOnly = false;
+	uint16 port = 10900;
-	uint32 listenPort = 10900;
+	uint16 sshPort = 22;
-	uint32 sshPort = 22;
+	int32 width = -1;
-	const char* command = NULL;
+	int32 height = -1;
+	bool useSSH = false;
+	const char *command = NULL;
+	const char *host = argv[1];
 
 	for (int32 i = 2; i < argc; i++) {
 		if (strcmp(argv[i], "-p") == 0) {
-			if (argc < i + 1 || sscanf(argv[i + 1], "%" B_PRIu32, &listenPort)
+			if (argc < i + 1 || sscanf(argv[i + 1], "%" B_SCNu16, &port)
 				!= 1) {
 				print_usage(argv[0]);
 				return 2;
@@ -63,9 +70,9 @@ main(int argc, char *argv[])
 			continue;
 		}
 
-		if (strcmp(argv[i], "-s") == 0) {
+		if (strcmp(argv[i], "-w") == 0) {
-			if (argc < i + 1 || sscanf(argv[i + 1], "%" B_PRIu32, &sshPort)
+			if (argc < i + 1 || sscanf(argv[i + 1], "%" B_SCNd32, &width) != 1)
-				!= 1) {
+			{
 				print_usage(argv[0]);
 				return 2;
 			}
@@ -74,6 +81,27 @@ main(int argc, char *argv[])
 			continue;
 		}
 
+		if (strcmp(argv[i], "-h") == 0) {
+			if (argc < i + 1 || sscanf(argv[i + 1], "%" B_SCNd32, &height) != 1)
+			{
+				print_usage(argv[0]);
+				return 2;
+			}
+
+			i++;
+			continue;
+		}
+
+		if (strcmp(argv[i], "-s") == 0) {
+			if (argc >= i + 1
+				&& sscanf(argv[i + 1], "%" B_SCNu16, &sshPort) == 1) {
+				i++;
+			}
+
+			useSSH = true;
+			continue;
+		}
+
 		if (strcmp(argv[i], "-c") == 0) {
 			if (argc < i + 1) {
 				print_usage(argv[0]);
@@ -85,17 +113,17 @@ main(int argc, char *argv[])
 			continue;
 		}
 
-		if (strcmp(argv[i], "--listenOnly") == 0) {
+		print_usage(argv[0]);
-			listenOnly = true;
+		return 2;
-			continue;
+	}
-		}
 
+	if (command != NULL && !useSSH) {
 		print_usage(argv[0]);
 		return 2;
 	}
 
 	pid_t sshPID = -1;
-	if (!listenOnly) {
+	if (useSSH) {
 		BPath terminalPath;
 		if (command == NULL) {
 			if (find_directory(B_SYSTEM_APPS_DIRECTORY, &terminalPath)
@@ -112,8 +140,8 @@ main(int argc, char *argv[])
 
 		char shellCommand[4096];
 		snprintf(shellCommand, sizeof(shellCommand),
-			"echo connected; export TARGET_SCREEN=localhost:%" B_PRIu32
+			"echo connected; export TARGET_SCREEN=%" B_PRIu16 "; %s\n", port,
-			"; %s\n", listenPort, command);
+			command);
 
 		int pipes[4];
 		if (pipe(&pipes[0]) != 0 || pipe(&pipes[2]) != 0) {
@@ -138,18 +166,14 @@ main(int argc, char *argv[])
 				close(pipes[i]);
 
 			char localRedirect[50];
-			sprintf(localRedirect, "localhost:%" B_PRIu32 ":localhost:%"
+			sprintf(localRedirect, "localhost:%" B_PRIu16 ":localhost:%"
-				B_PRIu32, listenPort + 1, listenPort + 1);
+				B_PRIu16, port, port);
-
-			char remoteRedirect[50];
-			sprintf(remoteRedirect, "localhost:%" B_PRIu32 ":localhost:%"
-				B_PRIu32, listenPort, listenPort);
 
 			char portNumber[10];
-			sprintf(portNumber, "%" B_PRIu32, sshPort);
+			sprintf(portNumber, "%" B_PRIu16, sshPort);
 
 			int result = execl("ssh", "-C", "-L", localRedirect,
-				"-R", remoteRedirect, "-p", portNumber, argv[1],
+				"-p", portNumber, "-o", "ExitOnForwardFailure=yes", host,
 				shellCommand, NULL);
 
 			// we don't get here unless there was an error in executing
@@ -162,12 +186,19 @@ main(int argc, char *argv[])
 			char buffer[10];
 			read(pipes[0], buffer, sizeof(buffer));
 				// block until connected/error message from ssh
+
+			host = "localhost";
 		}
 	}
 
 	BApplication app("application/x-vnd.Haiku-RemoteDesktop");
-	BScreen screen;
+	BRect windowFrame = BRect(0, 0, width - 1, height - 1);
-	BWindow *window = new(std::nothrow) BWindow(screen.Frame(), "RemoteDesktop",
+	if (!windowFrame.IsValid()) {
+		BScreen screen;
+		windowFrame = screen.Frame();
+	}
+
+	BWindow *window = new(std::nothrow) BWindow(windowFrame, "RemoteDesktop",
 		B_TITLED_WINDOW, B_QUIT_ON_WINDOW_CLOSE);
 
 	if (window == NULL) {
@@ -175,8 +206,8 @@ main(int argc, char *argv[])
 		return 4;
 	}
 
-	RemoteView *view = new(std::nothrow) RemoteView(window->Bounds(),
+	RemoteView *view = new(std::nothrow) RemoteView(window->Bounds(), host,
-		listenPort);
+		port);
 	if (view == NULL) {
 		printf("no memory to allocate remote view\n");
 		return 4;
@@ -195,7 +226,7 @@ main(int argc, char *argv[])
 	app.Run();
 
 	if (sshPID >= 0)
-		kill(sshPID, SIGINT);
+		kill(sshPID, SIGHUP);
 
 	return 0;
 }

src/apps/remotedesktop/RemoteView.cpp

@@ -54,15 +54,14 @@ typedef struct engine_state {
 } engine_state;
 
 
-RemoteView::RemoteView(BRect frame, uint16 listenPort)
+RemoteView::RemoteView(BRect frame, const char *remoteHost, uint16 remotePort)
 	:
 	BView(frame, "RemoteView", B_FOLLOW_NONE, B_WILL_DRAW),
 	fInitStatus(B_NO_INIT),
 	fIsConnected(false),
 	fReceiveBuffer(NULL),
 	fSendBuffer(NULL),
-	fReceiveEndpoint(NULL),
+	fEndpoint(NULL),
-	fSendEndpoint(NULL),
 	fReceiver(NULL),
 	fSender(NULL),
 	fStopThread(false),
@@ -94,38 +93,34 @@ RemoteView::RemoteView(BRect frame, uint16 listenPort)
 	if (fInitStatus != B_OK)
 		return;
 
-	fReceiveEndpoint = new(std::nothrow) BNetEndpoint();
+	fEndpoint = new(std::nothrow) BNetEndpoint();
-	if (fReceiveEndpoint == NULL) {
+	if (fEndpoint == NULL) {
 		fInitStatus = B_NO_MEMORY;
 		TRACE_ERROR("no memory available\n");
 		return;
 	}
 
-	fInitStatus = fReceiveEndpoint->Bind(listenPort);
+	fInitStatus = fEndpoint->Connect(remoteHost, remotePort);
-	if (fInitStatus != B_OK)
+	if (fInitStatus != B_OK) {
-		return;
+		TRACE_ERROR("failed to connect to %s:%" B_PRIu16 "\n",
-
+			remoteHost, remotePort);
-	fReceiver = new(std::nothrow) NetReceiver(fReceiveEndpoint, fReceiveBuffer);
-	if (fReceiver == NULL) {
-		fInitStatus = B_NO_MEMORY;
-		TRACE_ERROR("no memory available\n");
 		return;
 	}
 
-	fSendEndpoint = new(std::nothrow) BNetEndpoint();
+	fSender = new(std::nothrow) NetSender(fEndpoint, fSendBuffer);
-	if (fSendEndpoint == NULL) {
-		fInitStatus = B_NO_MEMORY;
-		TRACE_ERROR("no memory available\n");
-		return;
-	}
-
-	fSender = new(std::nothrow) NetSender(fSendEndpoint, fSendBuffer);
 	if (fSender == NULL) {
 		fInitStatus = B_NO_MEMORY;
 		TRACE_ERROR("no memory available\n");
 		return;
 	}
 
+	fReceiver = new(std::nothrow) NetReceiver(fEndpoint, fReceiveBuffer);
+	if (fReceiver == NULL) {
+		fInitStatus = B_NO_MEMORY;
+		TRACE_ERROR("no memory available\n");
+		return;
+	}
+
 	BRect bounds = frame.OffsetToCopy(0, 0);
 	fOffscreenBitmap = new(std::nothrow) BBitmap(bounds, B_BITMAP_ACCEPTS_VIEWS,
 		B_RGB32);
@@ -171,8 +166,7 @@ RemoteView::~RemoteView()
 	delete fSendBuffer;
 	delete fSender;
 
-	delete fReceiveEndpoint;
+	delete fEndpoint;
-	delete fSendEndpoint;
 
 	delete fOffscreenBitmap;
 	delete fCursorBitmap;
@@ -447,6 +441,9 @@ RemoteView::_DrawThread()
 	// cursor
 	BPoint cursorHotSpot(0, 0);
 
+	reply.Start(RP_INIT_CONNECTION);
+	reply.Flush();
+
 	while (!fStopThread) {
 		uint16 code;
 		status_t status = message.NextMessage(code);
@@ -470,34 +467,6 @@ RemoteView::_DrawThread()
 		switch (code) {
 			case RP_INIT_CONNECTION:
 			{
-				uint16 port;
-				status_t result = message.Read(port);
-				if (result != B_OK) {
-					TRACE_ERROR("failed to read remote port\n");
-					continue;
-				}
-
-				BNetEndpoint *endpoint = fReceiver->Endpoint();
-				if (endpoint == NULL) {
-					TRACE_ERROR("receiver not connected anymore\n");
-					continue;
-				}
-
-				in_addr remoteHost;
-				char hostName[MAXHOSTNAMELEN + 1];
-				BNetAddress address(endpoint->RemoteAddr());
-				address.GetAddr(remoteHost);
-				address.GetAddr(hostName, NULL);
-				address.SetTo(remoteHost, port);
-
-				TRACE("connecting to host \"%s\" port %u\n", hostName, port);
-				result = fSendEndpoint->Connect(address);
-				if (result != B_OK) {
-					TRACE_ERROR("failed to connect to host \"%s\" port %u\n",
-						hostName, port);
-					continue;
-				}
-
 				BRect bounds = fOffscreenBitmap->Bounds();
 				reply.Start(RP_UPDATE_DISPLAY_MODE);
 				reply.Add(bounds.IntegerWidth() + 1);

src/apps/remotedesktop/RemoteView.h

@@ -22,7 +22,9 @@ struct engine_state;
 
 class RemoteView : public BView {
 public:
-									RemoteView(BRect frame, uint16 listenPort);
+									RemoteView(BRect frame,
+										const char *remoteHost,
+										uint16 remotePort);
 virtual								~RemoteView();
 
 		status_t					InitCheck();
@@ -64,8 +66,7 @@ static	int32						_DrawEntry(void *data);
 
 		StreamingRingBuffer *		fReceiveBuffer;
 		StreamingRingBuffer *		fSendBuffer;
-		BNetEndpoint *				fReceiveEndpoint;
+		BNetEndpoint *				fEndpoint;
-		BNetEndpoint *				fSendEndpoint;
 		NetReceiver *				fReceiver;
 		NetSender *					fSender;
 

src/servers/app/ServerTokenSpace.h

@@ -17,6 +17,7 @@ using BPrivate::BTokenSpace;
 const int32 kCursorToken = 3;
 const int32 kBitmapToken = 4;
 const int32 kPictureToken = 5;
+const int32 kRemoteDrawingEngineToken = 6;
 
 
 extern BTokenSpace gTokenSpace;

src/servers/app/drawing/interface/remote/NetReceiver.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright 2009, Haiku, Inc.
+ * Copyright 2009, 2017, Haiku, Inc.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
@@ -21,13 +21,16 @@
 #define TRACE_ERROR(x...)	debug_printf("NetReceiver: " x)
 
 
-NetReceiver::NetReceiver(BNetEndpoint *listener, StreamingRingBuffer *target)
+NetReceiver::NetReceiver(BNetEndpoint *listener, StreamingRingBuffer *target,
+	NewConnectionCallback newConnectionCallback, void *newConnectionCookie)
 	:
 	fListener(listener),
 	fTarget(target),
 	fReceiverThread(-1),
 	fStopThread(false),
-	fEndpoint(NULL)
+	fNewConnectionCallback(newConnectionCallback),
+	fNewConnectionCookie(newConnectionCookie),
+	fEndpoint(newConnectionCallback == NULL ? listener : NULL)
 {
 	fReceiverThread = spawn_thread(_NetworkReceiverEntry, "network receiver",
 		B_NORMAL_PRIORITY, this);
@@ -38,79 +41,94 @@ NetReceiver::NetReceiver(BNetEndpoint *listener, StreamingRingBuffer *target)
 NetReceiver::~NetReceiver()
 {
 	fStopThread = true;
+	delete fEndpoint;
 
-	if (fEndpoint != NULL)
+	suspend_thread(fReceiverThread);
-		fEndpoint->Close();
+	resume_thread(fReceiverThread);
-
-	//int32 result;
-	//wait_for_thread(fReceiverThread, &result);
-		// TODO: find out why closing the endpoint doesn't notify the waiter
-
-	kill_thread(fReceiverThread);
 }
 
 
 int32
 NetReceiver::_NetworkReceiverEntry(void *data)
 {
-	return ((NetReceiver *)data)->_NetworkReceiver();
+	NetReceiver *receiver = (NetReceiver *)data;
+	if (receiver->fNewConnectionCallback)
+		return receiver->_Listen();
+	else
+		return receiver->_Transfer();
 }
 
 
 status_t
-NetReceiver::_NetworkReceiver()
+NetReceiver::_Listen()
 {
-	static const uint16_t shutdown_message[] = { RP_CLOSE_CONNECTION, 0, 0 };
-
 	status_t result = fListener->Listen();
 	if (result != B_OK) {
 		TRACE_ERROR("failed to listen on port: %s\n", strerror(result));
-		fTarget->Write(shutdown_message, sizeof(shutdown_message));
 		return result;
 	}
 
 	while (!fStopThread) {
-		fEndpoint = fListener->Accept(5000);
+		if (fEndpoint != NULL) {
-		if (fEndpoint == NULL) {
+			TRACE("closing previous connection\n");
-			fTarget->Write(shutdown_message, sizeof(shutdown_message));
+			delete fEndpoint;
-			return B_ERROR;
+			fEndpoint = NULL;
+		}
+
+		fEndpoint = fListener->Accept(5000);
+		if (fEndpoint == NULL) {
+			TRACE("got NULL endpoint from accept\n");
+			continue;
 		}
 
-		int32 errorCount = 0;
 		TRACE("new endpoint connection: %p\n", fEndpoint);
-		while (!fStopThread) {
+
-			uint8 buffer[4096];
+		if (fNewConnectionCallback != NULL
-			int32 readSize = fEndpoint->Receive(buffer, sizeof(buffer));
+			&& fNewConnectionCallback(fNewConnectionCookie, *fEndpoint) != B_OK)
-			if (readSize < 0) {
+		{
-				TRACE_ERROR("read failed, closing connection: %s\n",
+			TRACE("connection callback rejected connection\n");
-					strerror(readSize));
+			continue;
-				BNetEndpoint *endpoint = fEndpoint;
+		}
-				fEndpoint = NULL;
+
-				delete endpoint;
+		_Transfer();
-				fTarget->Write(shutdown_message, sizeof(shutdown_message));
+	}
-				return readSize;
+
+	return B_OK;
+}
+
+
+status_t
+NetReceiver::_Transfer()
+{
+	int32 errorCount = 0;
+
+	while (!fStopThread) {
+		uint8 buffer[4096];
+		int32 readSize = fEndpoint->Receive(buffer, sizeof(buffer));
+		if (readSize < 0) {
+			TRACE_ERROR("read failed, closing connection: %s\n",
+				strerror(readSize));
+			return readSize;
+		}
+
+		if (readSize == 0) {
+			TRACE("read 0 bytes, retrying\n");
+			snooze(100 * 1000);
+			errorCount++;
+			if (errorCount == 5) {
+				TRACE_ERROR("failed to read, assuming disconnect\n");
+				return B_ERROR;
 			}
 
-			if (readSize == 0) {
+			continue;
-				TRACE("read 0 bytes, retrying\n");
+		}
-				snooze(100 * 1000);
-				errorCount++;
-				if (errorCount == 5) {
-					TRACE_ERROR("failed to read, assuming disconnect\n");
-					break;
-				}
 
-				continue;
+		errorCount = 0;
-			}
+		status_t result = fTarget->Write(buffer, readSize);
-
+		if (result != B_OK) {
-			errorCount = 0;
+			TRACE_ERROR("writing to ring buffer failed: %s\n",
-			status_t result = fTarget->Write(buffer, readSize);
+				strerror(result));
-			if (result != B_OK) {
+			return result;
-				TRACE_ERROR("writing to ring buffer failed: %s\n",
-					strerror(result));
-				fTarget->Write(shutdown_message, sizeof(shutdown_message));
-				return result;
-			}
 		}
 	}
 

src/servers/app/drawing/interface/remote/NetReceiver.h

@@ -14,17 +14,23 @@
 class BNetEndpoint;
 class StreamingRingBuffer;
 
+typedef status_t (*NewConnectionCallback)(void *cookie, BNetEndpoint &endpoint);
+
+
 class NetReceiver {
 public:
-								NetReceiver(BNetEndpoint *listener,
+								NetReceiver(BNetEndpoint *endpoint,
-									StreamingRingBuffer *target);
+									StreamingRingBuffer *target,
+									NewConnectionCallback callback = NULL,
+									void *newConnectionCookie = NULL);
 								~NetReceiver();
 
 		BNetEndpoint *			Endpoint() { return fEndpoint; }
 
 private:
 static	int32					_NetworkReceiverEntry(void *data);
-		status_t				_NetworkReceiver();
+		status_t				_Listen();
+		status_t				_Transfer();
 
 		BNetEndpoint *			fListener;
 		StreamingRingBuffer *	fTarget;
@@ -32,6 +38,9 @@ static	int32					_NetworkReceiverEntry(void *data);
 		thread_id				fReceiverThread;
 		bool					fStopThread;
 
+		NewConnectionCallback	fNewConnectionCallback;
+		void *					fNewConnectionCookie;
+
 		BNetEndpoint *			fEndpoint;
 };
 

src/servers/app/drawing/interface/remote/NetSender.cpp

@@ -36,8 +36,9 @@ NetSender::NetSender(BNetEndpoint *endpoint, StreamingRingBuffer *source)
 NetSender::~NetSender()
 {
 	fStopThread = true;
-	int32 result;
+
-	wait_for_thread(fSenderThread, &result);
+	suspend_thread(fSenderThread);
+	resume_thread(fSenderThread);
 }
 
 

src/servers/app/drawing/interface/remote/RemoteDrawingEngine.cpp

@@ -11,6 +11,7 @@
 
 #include "BitmapDrawingEngine.h"
 #include "DrawState.h"
+#include "ServerTokenSpace.h"
 
 #include <Bitmap.h>
 #include <utf8_functions.h>
@@ -18,11 +19,16 @@
 #include <new>
 
 
+#define TRACE(x...)				/*debug_printf("RemoteDrawingEngine: " x)*/
+#define TRACE_ALWAYS(x...)		debug_printf("RemoteDrawingEngine: " x)
+#define TRACE_ERROR(x...)		debug_printf("RemoteDrawingEngine: " x)
+
+
 RemoteDrawingEngine::RemoteDrawingEngine(RemoteHWInterface* interface)
 	:
 	DrawingEngine(interface),
 	fHWInterface(interface),
-	fToken((addr_t)this),
+	fToken(gTokenSpace.NewToken(kRemoteDrawingEngineToken, this)),
 	fExtendWidth(0),
 	fCallbackAdded(false),
 	fResultNotify(-1),

src/servers/app/drawing/interface/remote/RemoteDrawingEngine.h

@@ -161,7 +161,7 @@ private:
 									UtilityBitmap**& bitmaps);
 
 			RemoteHWInterface*	fHWInterface;
-			addr_t				fToken;
+			int32				fToken;
 
 			DrawState			fState;
 			BRegion				fClippingRegion;

src/servers/app/drawing/interface/remote/RemoteHWInterface.cpp

@@ -38,14 +38,11 @@ RemoteHWInterface::RemoteHWInterface(const char* target)
 	:
 	HWInterface(),
 	fTarget(target),
-	fRemoteHost(NULL),
-	fRemotePort(10900),
 	fIsConnected(false),
 	fProtocolVersion(100),
 	fConnectionSpeed(0),
 	fListenPort(10901),
-	fSendEndpoint(NULL),
+	fListenEndpoint(NULL),
-	fReceiveEndpoint(NULL),
 	fSendBuffer(NULL),
 	fReceiveBuffer(NULL),
 	fSender(NULL),
@@ -58,32 +55,20 @@ RemoteHWInterface::RemoteHWInterface(const char* target)
 	fDisplayMode.virtual_height = 480;
 	fDisplayMode.space = B_RGB32;
 
-	fRemoteHost = strdup(fTarget);
-	char *portStart = strchr(fRemoteHost, ':');
-	if (portStart != NULL) {
-		portStart[0] = 0;
-		portStart++;
-		if (sscanf(portStart, "%" B_PRIu32, &fRemotePort) != 1) {
-			fInitStatus = B_BAD_VALUE;
-			return;
-		}
 
-		fListenPort = fRemotePort + 1;
+
+	if (sscanf(fTarget, "%" B_SCNu16, &fListenPort) != 1) {
+		fInitStatus = B_BAD_VALUE;
+		return;
 	}
 
-	fSendEndpoint = new(std::nothrow) BNetEndpoint();
+	fListenEndpoint = new(std::nothrow) BNetEndpoint();
-	if (fSendEndpoint == NULL) {
+	if (fListenEndpoint == NULL) {
 		fInitStatus = B_NO_MEMORY;
 		return;
 	}
 
-	fReceiveEndpoint = new(std::nothrow) BNetEndpoint();
+	fInitStatus = fListenEndpoint->Bind(fListenPort);
-	if (fReceiveEndpoint == NULL) {
-		fInitStatus = B_NO_MEMORY;
-		return;
-	}
-
-	fInitStatus = fReceiveEndpoint->Bind(fListenPort);
 	if (fInitStatus != B_OK)
 		return;
 
@@ -107,13 +92,8 @@ RemoteHWInterface::RemoteHWInterface(const char* target)
 	if (fInitStatus != B_OK)
 		return;
 
-	fSender = new(std::nothrow) NetSender(fSendEndpoint, fSendBuffer);
+	fReceiver = new(std::nothrow) NetReceiver(fListenEndpoint, fReceiveBuffer,
-	if (fSender == NULL) {
+		_NewConnectionCallback, this);
-		fInitStatus = B_NO_MEMORY;
-		return;
-	}
-
-	fReceiver = new(std::nothrow) NetReceiver(fReceiveEndpoint, fReceiveBuffer);
 	if (fReceiver == NULL) {
 		fInitStatus = B_NO_MEMORY;
 		return;
@@ -125,11 +105,6 @@ RemoteHWInterface::RemoteHWInterface(const char* target)
 		return;
 	}
 
-	fSendEndpoint->SetTimeout(3 * 1000 * 1000);
-	fInitStatus = _Connect();
-	if (fInitStatus != B_OK)
-		return;
-
 	fEventThread = spawn_thread(_EventThreadEntry, "remote event thread",
 		B_NORMAL_PRIORITY, this);
 	if (fEventThread < 0) {
@@ -149,12 +124,9 @@ RemoteHWInterface::~RemoteHWInterface()
 	delete fSendBuffer;
 	delete fSender;
 
-	delete fReceiveEndpoint;
+	delete fListenEndpoint;
-	delete fSendEndpoint;
 
 	delete fEventStream;
-
-	free(fRemoteHost);
 }
 
 
@@ -273,10 +245,28 @@ RemoteHWInterface::_EventThread()
 		}
 
 		switch (code) {
+			case RP_INIT_CONNECTION:
+			{
+				RemoteMessage reply(NULL, fSendBuffer);
+				reply.Start(RP_INIT_CONNECTION);
+				status_t result = reply.Flush();
+				TRACE("init connection result: %s\n", strerror(result));
+				break;
+			}
+
 			case RP_UPDATE_DISPLAY_MODE:
 			{
-				// TODO: implement, we only handle it in the context of the
+				int32 width, height;
-				// initial mode setup on connect
+				message.Read(width);
+				result = message.Read(height);
+				if (result != B_OK) {
+					TRACE_ERROR("failed to read display mode\n");
+					break;
+				}
+
+				fIsConnected = true;
+				fDisplayMode.virtual_width = width;
+				fDisplayMode.virtual_height = height;
 				break;
 			}
 
@@ -298,49 +288,32 @@ RemoteHWInterface::_EventThread()
 
 
 status_t
-RemoteHWInterface::_Connect()
+RemoteHWInterface::_NewConnectionCallback(void *cookie, BNetEndpoint &endpoint)
 {
-	TRACE("connecting to host \"%s\" port %" B_PRIu32 "\n", fRemoteHost, fRemotePort);
+	return ((RemoteHWInterface *)cookie)->_NewConnection(endpoint);
-	status_t result = fSendEndpoint->Connect(fRemoteHost, (uint16)fRemotePort);
+}
-	if (result != B_OK) {
+
-		TRACE_ERROR("failed to connect to host \"%s\" port %" B_PRIu32 "\n",
+
-			fRemoteHost, fRemotePort);
+status_t
-		return result;
+RemoteHWInterface::_NewConnection(BNetEndpoint &endpoint)
+{
+	if (fSender != NULL) {
+		delete fSender;
+		fSender = NULL;
 	}
 
-	RemoteMessage message(fReceiveBuffer, fSendBuffer);
+	fSendBuffer->MakeEmpty();
-	message.Start(RP_INIT_CONNECTION);
+
-	message.Add(fListenPort);
+	BNetEndpoint *sendEndpoint = new(std::nothrow) BNetEndpoint(endpoint);
-	result = message.Flush();
+	if (sendEndpoint == NULL)
-	if (result != B_OK) {
+		return B_NO_MEMORY;
-		TRACE_ERROR("failed to send init connection message\n");
+
-		return result;
+	fSender = new(std::nothrow) NetSender(sendEndpoint, fSendBuffer);
+	if (fSender == NULL) {
+		delete sendEndpoint;
+		return B_NO_MEMORY;
 	}
 
-	uint16 code;
-	result = message.NextMessage(code);
-	if (result != B_OK) {
-		TRACE_ERROR("failed to read message from receiver: %s\n",
-			strerror(result));
-		return result;
-	}
-
-	TRACE("code %u with %lu bytes of data\n", code, message.DataLeft());
-	if (code != RP_UPDATE_DISPLAY_MODE) {
-		TRACE_ERROR("invalid connection init code %u\n", code);
-		return B_ERROR;
-	}
-
-	int32 width, height;
-	message.Read(width);
-	result = message.Read(height);
-	if (result != B_OK) {
-		TRACE_ERROR("failed to get initial display mode\n");
-		return result;
-	}
-
-	fDisplayMode.virtual_width = width;
-	fDisplayMode.virtual_height = height;
 	return B_OK;
 }
 
@@ -355,10 +328,8 @@ RemoteHWInterface::_Disconnect()
 		fIsConnected = false;
 	}
 
-	if (fSendEndpoint != NULL)
+	if (fListenEndpoint != NULL)
-		fSendEndpoint->Close();
+		fListenEndpoint->Close();
-	if (fReceiveEndpoint != NULL)
-		fReceiveEndpoint->Close();
 }
 
 

src/servers/app/drawing/interface/remote/RemoteHWInterface.h

@@ -97,13 +97,14 @@ static	int							_CallbackCompare(const uint32* key,
 static	int32						_EventThreadEntry(void* data);
 		status_t					_EventThread();
 
-		status_t					_Connect();
+static	status_t					_NewConnectionCallback(void *cookie,
+										BNetEndpoint &endpoint);
+		status_t					_NewConnection(BNetEndpoint &endpoint);
+
 		void						_Disconnect();
 
-		const char*					fTarget;
-		char*						fRemoteHost;
-		uint32						fRemotePort;
 
+		const char*					fTarget;
 		status_t					fInitStatus;
 		bool						fIsConnected;
 		uint32						fProtocolVersion;
@@ -111,9 +112,7 @@ static	int32						_EventThreadEntry(void* data);
 		display_mode				fDisplayMode;
 		uint16						fListenPort;
 
-		BNetEndpoint*				fSendEndpoint;
+		BNetEndpoint*				fListenEndpoint;
-		BNetEndpoint*				fReceiveEndpoint;
-
 		StreamingRingBuffer*		fSendBuffer;
 		StreamingRingBuffer*		fReceiveBuffer;
 

src/servers/app/drawing/interface/remote/StreamingRingBuffer.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright 2009, Haiku, Inc.
+ * Copyright 2009, 2017, Haiku, Inc.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
@@ -14,14 +14,23 @@
 #include <stdlib.h>
 #include <string.h>
 
-#define TRACE(x...)			/*debug_printf("StreamingRingBuffer: "x)*/
+
-#define TRACE_ERROR(x...)	debug_printf("StreamingRingBuffer: "x)
+#ifdef CLIENT_COMPILE
+#define TRACE_ALWAYS(x...)		printf("StreamingRingBuffer: " x)
+#else
+#define TRACE_ALWAYS(x...)		debug_printf("StreamingRingBuffer: " x)
+#endif
+
+#define TRACE(x...)				/*TRACE_ALWAYS(x)*/
+#define TRACE_ERROR(x...)		TRACE_ALWAYS(x)
 
 
 StreamingRingBuffer::StreamingRingBuffer(size_t bufferSize)
 	:
 	fReaderWaiting(false),
 	fWriterWaiting(false),
+	fCancelRead(false),
+	fCancelWrite(false),
 	fReaderNotifier(-1),
 	fWriterNotifier(-1),
 	fReaderLocker("StreamingRingBuffer reader"),
@@ -91,14 +100,23 @@ StreamingRingBuffer::Read(void *buffer, size_t length, bool onlyBlockOnNoData)
 			do {
 				TRACE("waiting in reader\n");
 				result = acquire_sem(fReaderNotifier);
-				TRACE("done waiting in reader with status: 0x%08lx\n", result);
+				TRACE("done waiting in reader with status: %#" B_PRIx32 "\n",
+					result);
 			} while (result == B_INTERRUPTED);
 
 			if (result != B_OK)
 				return result;
 
-			if (!dataLock.Lock())
+			if (!dataLock.Lock()) {
+				TRACE_ERROR("failed to acquire data lock\n");
 				return B_ERROR;
+			}
+
+			if (fCancelRead) {
+				TRACE("read canceled\n");
+				fCancelRead = false;
+				return B_CANCELED;
+			}
 
 			continue;
 		}
@@ -147,14 +165,23 @@ StreamingRingBuffer::Write(const void *buffer, size_t length)
 			do {
 				TRACE("waiting in writer\n");
 				result = acquire_sem(fWriterNotifier);
-				TRACE("done waiting in writer with status: 0x%08lx\n", result);
+				TRACE("done waiting in writer with status: %#" B_PRIx32 "\n",
+					result);
 			} while (result == B_INTERRUPTED);
 
 			if (result != B_OK)
 				return result;
 
-			if (!dataLock.Lock())
+			if (!dataLock.Lock()) {
+				TRACE_ERROR("failed to acquire data lock\n");
 				return B_ERROR;
+			}
+
+			if (fCancelWrite) {
+				TRACE("write canceled\n");
+				fCancelWrite = false;
+				return B_CANCELED;
+			}
 
 			continue;
 		}
@@ -174,3 +201,27 @@ StreamingRingBuffer::Write(const void *buffer, size_t length)
 
 	return B_OK;
 }
+
+
+void
+StreamingRingBuffer::MakeEmpty()
+{
+	BAutolock dataLock(fDataLocker);
+	if (!dataLock.IsLocked())
+		return;
+
+	fReadPosition = fWritePosition = 0;
+	fReadable = 0;
+
+	if (fWriterWaiting) {
+		release_sem_etc(fWriterNotifier, 1, 0);
+		fWriterWaiting = false;
+		fCancelWrite = true;
+	}
+
+	if (fReaderWaiting) {
+		release_sem_etc(fReaderNotifier, 1, 0);
+		fReaderWaiting = false;
+		fCancelRead = true;
+	}
+}

src/servers/app/drawing/interface/remote/StreamingRingBuffer.h

@@ -24,12 +24,13 @@ public:
 									bool onlyBlockOnNoData = false);
 		status_t				Write(const void *buffer, size_t length);
 
-private:
+		void					MakeEmpty();
-		bool					_Lock();
-		void					_Unlock();
 
+private:
 		bool					fReaderWaiting;
 		bool					fWriterWaiting;
+		bool					fCancelRead;
+		bool					fCancelWrite;
 		sem_id					fReaderNotifier;
 		sem_id					fWriterNotifier;