Temporarily spawn openbox if no WM is running

3 files changed, 71 insertions, 0 deletions

diff --git a/src/dialog.cpp b/src/dialog.cpp
index a23e3ce..932f28c 100644
--- a/src/dialog.cpp
+++ b/src/dialog.cpp
@@ -22,11 +22,16 @@
 #include "vsession.h"
 #include "userconfig.h"
 #include "filedownloader.h"
+#include "windowmanager.h"
 
 static bool isProcessRunning(const QString &binary);
 
 Dialog::Dialog(QWidget *parent)
     : QDialog(parent), ui(new Ui::Dialog) {
+
+    // Make sure a window manager is running, so any modals or other popups work properly
+    WindowManager::ensureRunning();
+
     model_[TAB_NATIVE] = new SessionTreeModel(parent);
     model_[TAB_RECENT_COURSES] = new SessionTreeModel(parent, true);
     model_[TAB_ALL_VMS] = new SessionTreeModel(parent);
@@ -153,6 +158,7 @@ void Dialog::on_treeView_doubleClicked(const QModelIndex& index)
 
     // Run session
     if (s->run()) {
+        WindowManager::stopOwnInstance();
         // Run session start script if the session could be initialized successfully
         if (QFile::exists(SESSION_START_SCRIPT)) {
             // Use the current environment variables and add the necessary
diff --git a/src/windowmanager.cpp b/src/windowmanager.cpp
new file mode 100644
index 0000000..e5e14a3
--- /dev/null
+++ b/src/windowmanager.cpp
@@ -0,0 +1,43 @@
+#include "windowmanager.h"
+
+#include <QProcess>
+#include <QTimer>
+#include <QDebug>
+
+namespace WindowManager {
+
+static QProcess wm;
+
+void ensureRunning()
+{
+    wm.start(QLatin1String("openbox"));
+    wm.closeReadChannel(QProcess::StandardError);
+    wm.closeReadChannel(QProcess::StandardOutput);
+    wm.closeWriteChannel();
+    wm.waitForStarted(1000);
+    QTimer::singleShot(200, []() {
+        if (wm.state() == QProcess::Running) {
+            qDebug() << "- Spawned openbox";
+        } else if (wm.exitCode() == 0) {
+            qDebug() << "- A WM is already running";
+        } else {
+            qDebug() << "- openbox binary not in $PATH";
+        }
+    });
+}
+
+void stopOwnInstance()
+{
+    if (wm.state() == QProcess::Running) {
+        qDebug() << "- Politely terminating spawned WM";
+        wm.terminate();
+        QTimer::singleShot(1000, []() {
+            if (wm.state() == QProcess::Running) {
+                qDebug() << "- Forcefully killing spawned WM";
+                wm.kill();
+            }
+        });
+    }
+}
+
+}
diff --git a/src/windowmanager.h b/src/windowmanager.h
new file mode 100644
index 0000000..c89f983
--- /dev/null
+++ b/src/windowmanager.h
@@ -0,0 +1,22 @@
+#ifndef _WINDOWSMANAGER_H_
+#define _WINDOWSMANAGER_H_
+
+namespace WindowManager
+{
+
+/**
+ * Make sure a window manager is running.
+ * If none is running, start openbox.
+ */
+void ensureRunning();
+
+/**
+ * If we started openbox as the window manager,
+ * terminate it, otherwise leave the current
+ * one running.
+ */
+void stopOwnInstance();
+
+}
+
+#endif