mainwindow: detect secondary instances of Jami and restore primary

- connects a qt socket to the primary instance running a local
  server to inform the primary instance that it should restore
  from a possibly minimized state

Change-Id: Iceda1a5a8be9fda2d34d41d9d32b6c02f26d06e3
Gitlab: #480

main.cpp

@@ -21,6 +21,7 @@
 
 #include <QApplication>
 #include <QFile>
+#include <QMessageBox>
 
 #include "callmodel.h"
 #include "globalinstances.h"
@@ -105,13 +106,6 @@ fileDebug(QFile& debugFile)
 int
 main(int argc, char* argv[])
 {
-    RunGuard guard("680b3e5eaf");
-    if (!guard.tryToRun())
-        return 0;
-
-    QApplication::setAttribute(Qt::AA_DisableHighDpiScaling);
-    QGuiApplication::setAttribute(Qt::AA_UseHighDpiPixmaps);
-
     char ARG_DISABLE_WEB_SECURITY[] = "--disable-web-security";
     int newArgc = argc + 1 + 1;
     char** newArgv = new char*[newArgc];
@@ -127,12 +121,20 @@ main(int argc, char* argv[])
 
     QApplication a(newArgc, newArgv);
 
+    QCoreApplication::setApplicationName("Ring");
+    QCoreApplication::setOrganizationDomain("jami.net");
+
+    QCryptographicHash appData(QCryptographicHash::Sha256);
+    appData.addData(QApplication::applicationName().toUtf8());
+    appData.addData(QApplication::organizationDomain().toUtf8());
+    RunGuard guard(appData.result());
+    if (!guard.tryToRun()) {
+        return 0;
+    }
+
     QApplication::setAttribute(Qt::AA_EnableHighDpiScaling, false);
     QGuiApplication::setAttribute(Qt::AA_UseHighDpiPixmaps);
 
-    QCoreApplication::setOrganizationDomain("jami.net");
-    QCoreApplication::setApplicationName("Ring");
-
     auto startMinimized = false;
     QString uri = "";
 

ring-client-windows.vcxproj

@@ -443,7 +443,10 @@
     <ClInclude Include="ringthemeutils.h" />
     <QtMoc Include="selectareadialog.h">
     </QtMoc>
-    <ClInclude Include="runguard.h" />
+    <QtMoc Include="runguard.h">
+      <IncludePath Condition="'$(Configuration)|$(Platform)'=='Release|x64'">.\GeneratedFiles\$(ConfigurationName);.\GeneratedFiles;.;$(ProjectDir)..\ring-daemon\contrib\msvc\include;$(ProjectDir)..\daemon\contrib\msvc\include;$(ProjectDir)..\ring-lrc\src;$(ProjectDir)..\lrc\src;$(ProjectDir)qrencode-win32\qrencode-win32;$(QTDIR)\include;$(QTDIR)\include\QtSvg;$(QTDIR)\include\QtWidgets;$(QTDIR)\include\QtWinExtras;$(QTDIR)\include\QtGui;$(QTDIR)\include\QtANGLE;$(QTDIR)\include\QtXml;$(QTDIR)\include\QtNetwork;$(QTDIR)\include\QtWebEngineWidgets;$(QTDIR)\include\QtWebChannel;$(QTDIR)\include\QtCore;$(QTDIR)\mkspecs\win32-msvc;.\release</IncludePath>
+      <IncludePath Condition="'$(Configuration)|$(Platform)'=='ReleaseCompile|x64'">.\GeneratedFiles\$(ConfigurationName);.\GeneratedFiles;.;$(ProjectDir)..\ring-daemon\contrib\msvc\include;$(ProjectDir)..\daemon\contrib\msvc\include;$(ProjectDir)..\ring-lrc\src;$(ProjectDir)..\lrc\src;$(ProjectDir)winsparkle\include;$(ProjectDir)qrencode-win32\qrencode-win32;$(QTDIR)\include;$(QTDIR)\include\QtSvg;$(QTDIR)\include\QtWidgets;$(QTDIR)\include\QtWinExtras;$(QTDIR)\include\QtGui;$(QTDIR)\include\QtANGLE;$(QTDIR)\include\QtXml;$(QTDIR)\include\QtNetwork;$(QTDIR)\include\QtWebEngineWidgets;$(QTDIR)\include\QtWebChannel;$(QTDIR)\include\QtCore;$(QTDIR)\mkspecs\win32-msvc;.\release</IncludePath>
+    </QtMoc>
     <ClInclude Include="settingskey.h" />
     <QtMoc Include="smartlistview.h">
       <IncludePath Condition="'$(Configuration)|$(Platform)'=='Release|x64'">.\GeneratedFiles\$(ConfigurationName)\.;.\GeneratedFiles;.;$(ProjectDir)..\daemon\contrib\msvc\include;$(ProjectDir)..\lrc\src;$(ProjectDir)..\client-windows\winsparkle\include;$(ProjectDir)..\client-windows\qrencode-win32\qrencode-win32;$(QTDIR)\include;$(QTDIR)\include\QtSvg;$(QTDIR)\include\QtWidgets;$(QTDIR)\include\QtWinExtras;$(QTDIR)\include\QtGui;$(QTDIR)\include\QtANGLE;$(QTDIR)\include\QtXml;$(QTDIR)\include\QtNetwork;$(QTDIR)\include\QtCore;$(QTDIR)\mkspecs\win32-msvc;.\release</IncludePath>

ring-client-windows.vcxproj.filters

@@ -359,6 +359,9 @@
     <QtMoc Include="downloadmanager.h">
       <Filter>Header Files</Filter>
     </QtMoc>
+    <QtMoc Include="runguard.h">
+      <Filter>Header Files</Filter>
+    </QtMoc>
   </ItemGroup>
   <ItemGroup>
     <CustomBuild Include="debug\moc_predefs.h.cbt">
@@ -789,8 +792,5 @@
     <ClInclude Include="version.h">
       <Filter>Header Files</Filter>
     </ClInclude>
-    <ClInclude Include="runguard.h">
-      <Filter>Header Files</Filter>
-    </ClInclude>
   </ItemGroup>
 </Project>
\ No newline at end of file

runguard.cpp

-// From: https://stackoverflow.com/a/28172162
+/***************************************************************************
+ * Copyright (C) 2019 by Savoir-faire Linux                                *
+ * Author: Andreas Traczyk <andreas.traczyk@savoirfairelinux.com>          *
+ *                                                                         *
+ * This program is free software; you can redistribute it and/or modify    *
+ * it under the terms of the GNU General Public License as published by    *
+ * the Free Software Foundation; either version 3 of the License, or       *
+ * (at your option) any later version.                                     *
+ *                                                                         *
+ * This program is distributed in the hope that it will be useful,         *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of          *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the           *
+ * GNU General Public License for more details.                            *
+ *                                                                         *
+ * You should have received a copy of the GNU General Public License       *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.   *
+ **************************************************************************/
+ // Based on: https://stackoverflow.com/a/28172162
 
 #include "runguard.h"
 
 #include <QCryptographicHash>
 
+#include "mainwindow.h"
+
 namespace
 {
 
@@ -21,59 +40,85 @@ QString generateKeyHash(const QString& key, const QString& salt)
 }
 
 RunGuard::RunGuard(const QString& key)
-    : key(key)
-    , memLockKey(generateKeyHash(key, "_memLockKey"))
-    , sharedmemKey(generateKeyHash(key, "_sharedmemKey"))
-    , sharedMem(sharedmemKey)
-    , memLock(memLockKey, 1)
-{
-    memLock.acquire();
-    {
-        QSharedMemory fix(sharedmemKey);    // Fix for *nix: http://habrahabr.ru/post/173281/
-        fix.attach();
-    }
-    memLock.release();
-}
+    : key_(key)
+    , memLockKey_(generateKeyHash(key, "_memLockKey"))
+    , sharedmemKey_(generateKeyHash(key, "_sharedmemKey"))
+    , sharedMem_(sharedmemKey_)
+    , memLock_(memLockKey_, 1)
+{}
 
 RunGuard::~RunGuard()
 {
     release();
 }
 
+void
+RunGuard::tryRestorePrimaryInstance()
+{
+    MainWindow::instance().showWindow();
+}
+
 bool RunGuard::isAnotherRunning()
 {
-    if (sharedMem.isAttached())
+    if (sharedMem_.isAttached())
         return false;
 
-    memLock.acquire();
-    const bool isRunning = sharedMem.attach();
+    memLock_.acquire();
+    const bool isRunning = sharedMem_.attach();
     if (isRunning)
-        sharedMem.detach();
-    memLock.release();
+        sharedMem_.detach();
+    memLock_.release();
 
     return isRunning;
 }
 
 bool RunGuard::tryToRun()
 {
-    if (isAnotherRunning())   // Extra check
+    if (isAnotherRunning()) {
+        // This is a secondary instance,
+        // connect to the primary instance to trigger a restore
+        // then fail.
+        if (socket_ == nullptr) {
+            socket_ = new QLocalSocket();
+        }
+        if (socket_->state() == QLocalSocket::UnconnectedState ||
+            socket_->state() == QLocalSocket::ClosingState) {
+            socket_->connectToServer(key_);
+        }
+        if (socket_->state() == QLocalSocket::ConnectingState) {
+            socket_->waitForConnected();
+        }
         return false;
+    }
 
-    memLock.acquire();
-    const bool result = sharedMem.create(sizeof(quint64));
-    memLock.release();
+    memLock_.acquire();
+    const bool result = sharedMem_.create(sizeof(quint64));
+    memLock_.release();
     if (!result) {
         release();
         return false;
     }
 
+    // This is the primary instance,
+    // listen for subsequent instances.
+    QLocalServer::removeServer(key_);
+    server_ = new QLocalServer();
+    server_->setSocketOptions(QLocalServer::UserAccessOption);
+    server_->listen(key_);
+    QObject::connect(
+        server_,
+        &QLocalServer::newConnection,
+        this,
+        &RunGuard::tryRestorePrimaryInstance
+    );
+
     return true;
 }
 
 void RunGuard::release()
 {
-    memLock.acquire();
-    if (sharedMem.isAttached())
-        sharedMem.detach();
-    memLock.release();
+    memLock_.acquire();
+    if (sharedMem_.isAttached())
+        sharedMem_.detach();
+    memLock_.release();
 }
\ No newline at end of file

runguard.h

-// From: https://stackoverflow.com/a/28172162
+/***************************************************************************
+ * Copyright (C) 2019 by Savoir-faire Linux                                *
+ * Author: Andreas Traczyk <andreas.traczyk@savoirfairelinux.com>          *
+ *                                                                         *
+ * This program is free software; you can redistribute it and/or modify    *
+ * it under the terms of the GNU General Public License as published by    *
+ * the Free Software Foundation; either version 3 of the License, or       *
+ * (at your option) any later version.                                     *
+ *                                                                         *
+ * This program is distributed in the hope that it will be useful,         *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of          *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the           *
+ * GNU General Public License for more details.                            *
+ *                                                                         *
+ * You should have received a copy of the GNU General Public License       *
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.   *
+ **************************************************************************/
+// Based on: https://stackoverflow.com/a/28172162
 
 #pragma once
 
 #include <QObject>
 #include <QSharedMemory>
 #include <QSystemSemaphore>
+#include <QtNetwork/QLocalServer>
+#include <QtNetwork/QLocalSocket>
 
-class RunGuard
+class RunGuard : public QObject
 {
-
+    Q_OBJECT;
 public:
     RunGuard(const QString& key);
     ~RunGuard();
@@ -17,13 +36,19 @@ public:
     bool tryToRun();
     void release();
 
+private slots:
+    void tryRestorePrimaryInstance();
+
 private:
-    const QString key;
-    const QString memLockKey;
-    const QString sharedmemKey;
+    const QString key_;
+    const QString memLockKey_;
+    const QString sharedmemKey_;
+
+    QSharedMemory sharedMem_;
+    QSystemSemaphore memLock_;
 
-    QSharedMemory sharedMem;
-    QSystemSemaphore memLock;
+    QLocalSocket *socket_;
+    QLocalServer *server_;
 
     Q_DISABLE_COPY(RunGuard)
 };
\ No newline at end of file