Merge pull request #4245 from ctrlaltdavid/20301

CR for Job #20301 - Windows: If I'm running Interface go to a place via hifi://, don't start another instance of the app

interface/src/Application.cpp

@@ -23,6 +23,7 @@
 // include this before QGLWidget, which includes an earlier version of OpenGL
 #include "InterfaceConfig.h"
 
+#include <QAbstractNativeEventFilter>
 #include <QActionGroup>
 #include <QColorDialog>
 #include <QDesktopWidget>
@@ -144,6 +145,37 @@ const QString SKIP_FILENAME = QStandardPaths::writableLocation(QStandardPaths::D
 
 const QString DEFAULT_SCRIPTS_JS_URL = "http://s3.amazonaws.com/hifi-public/scripts/defaultScripts.js";
 
+#ifdef Q_OS_WIN
+class MyNativeEventFilter : public QAbstractNativeEventFilter {
+public:
+    static MyNativeEventFilter& getInstance() {
+        static MyNativeEventFilter staticInstance;
+        return staticInstance;
+    }
+
+    bool nativeEventFilter(const QByteArray &eventType, void* msg, long* result) Q_DECL_OVERRIDE {
+        if (eventType == "windows_generic_MSG") {
+            MSG* message = (MSG*)msg;
+            if (message->message == UWM_IDENTIFY_INSTANCES) {
+                *result = UWM_IDENTIFY_INSTANCES;
+                return true;
+            }
+            if (message->message == WM_SHOWWINDOW) {
+                Application::getInstance()->getWindow()->showNormal();
+            }
+            if (message->message == WM_COPYDATA) {
+                COPYDATASTRUCT* pcds = (COPYDATASTRUCT*)(message->lParam);
+                QUrl url = QUrl((const char*)(pcds->lpData));
+                if (url.isValid() && url.scheme() == HIFI_URL_SCHEME) {
+                    DependencyManager::get<AddressManager>()->handleLookupString(url.toString());
+                }
+            }
+        }
+        return false;
+    }
+};
+#endif
+
 void messageHandler(QtMsgType type, const QMessageLogContext& context, const QString& message) {
     QString logMessage = LogHandler::getInstance().printMessage((LogMsgType) type, context, message);
     
@@ -244,6 +276,10 @@ Application::Application(int& argc, char** argv, QElapsedTimer &startup_time) :
         _aboutToQuit(false),
         _notifiedPacketVersionMismatchThisDomain(false)
 {
+#ifdef Q_OS_WIN
+    installNativeEventFilter(&MyNativeEventFilter::getInstance());
+#endif
+
     _logger = new FileLogger(this);  // After setting organization name in order to get correct directory
     qInstallMessageHandler(messageHandler);
 

interface/src/Application.h

@@ -114,6 +114,11 @@ static const quint64 TOO_LONG_SINCE_LAST_SEND_DOWNSTREAM_AUDIO_STATS = 1 * USECS
 static const QString INFO_HELP_PATH = "html/interface-welcome-allsvg.html";
 static const QString INFO_EDIT_ENTITIES_PATH = "html/edit-entities-commands.html";
 
+#ifdef Q_OS_WIN
+static const UINT UWM_IDENTIFY_INSTANCES = 
+    RegisterWindowMessage("UWM_IDENTIFY_INSTANCES_{8AB82783-B74A-4258-955B-8188C22AA0D6}");
+#endif
+
 class Application;
 #if defined(qApp)
 #undef qApp

interface/src/main.cpp

@@ -15,9 +15,53 @@
 
 #include <SharedUtil.h>
 
+#include "AddressManager.h"
 #include "Application.h"
 
+#ifdef Q_OS_WIN
+static BOOL CALLBACK enumWindowsCallback(HWND hWnd, LPARAM lParam) {
+    const UINT TIMEOUT = 200;  // ms
+    DWORD response;
+    LRESULT result = SendMessageTimeout(hWnd, UWM_IDENTIFY_INSTANCES, 0, 0, SMTO_BLOCK | SMTO_ABORTIFHUNG, TIMEOUT, &response);
+    if (result == 0) {  // Timeout; continue search.
+        return TRUE;
+    }
+    if (response == UWM_IDENTIFY_INSTANCES) {
+        HWND* target = (HWND*)lParam;
+        *target = hWnd;
+        return FALSE;  // Found; terminate search.
+    }
+    return TRUE;  // Not found; continue search.
+}
+#endif
+
+
 int main(int argc, const char * argv[]) {
+
+#ifdef Q_OS_WIN
+    // Run only one instance of Interface at a time.
+    HANDLE mutex = CreateMutex(NULL, FALSE, "High Fidelity Interface");
+    DWORD result = GetLastError();
+    if (result == ERROR_ALREADY_EXISTS || result == ERROR_ACCESS_DENIED) {
+        // Interface is already running.
+        HWND otherInstance = NULL;
+        EnumWindows(enumWindowsCallback, (LPARAM)&otherInstance);
+        if (otherInstance) {
+            ShowWindow(otherInstance, SW_RESTORE);
+            SetForegroundWindow(otherInstance);
+
+            QUrl url = QUrl(argv[1]);
+            if (url.isValid() && url.scheme() == HIFI_URL_SCHEME) {
+                COPYDATASTRUCT cds;
+                cds.cbData = strlen(argv[1]) + 1;
+                cds.lpData = (PVOID)argv[1];
+                SendMessage(otherInstance, WM_COPYDATA, 0, (LPARAM)&cds);
+            }
+        }
+        return 0;
+    }
+#endif
+
     QElapsedTimer startupTime;
     startupTime.start();
     
@@ -44,6 +88,11 @@ int main(int argc, const char * argv[]) {
         qDebug( "Created QT Application.");
         exitCode = app.exec();
     }
+
+#ifdef Q_OS_WIN
+    ReleaseMutex(mutex);
+#endif
+
     qDebug("Normal exit.");
     return exitCode;
 }