proof all dialogs against use-after-free when closing main window while a dialog is open

src/frontend/qt_sdl/AudioSettingsDialog.cpp

@@ -170,6 +170,12 @@ void AudioSettingsDialog::on_AudioSettingsDialog_accepted()
 
 void AudioSettingsDialog::on_AudioSettingsDialog_rejected()
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        closeDlg();
+        return;
+    }
+
     auto& cfg = emuInstance->getGlobalConfig();
     auto& instcfg = emuInstance->getLocalConfig();
     cfg.SetInt("Audio.Interpolation", oldInterp);

src/frontend/qt_sdl/CameraSettingsDialog.cpp

@@ -163,6 +163,12 @@ void CameraSettingsDialog::on_CameraSettingsDialog_accepted()
 
 void CameraSettingsDialog::on_CameraSettingsDialog_rejected()
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        closeDlg();
+        return;
+    }
+
     for (int i = 0; i < 2; i++)
     {
         camManager[i]->stop();

src/frontend/qt_sdl/EmuSettingsDialog.cpp

@@ -215,6 +215,13 @@ void EmuSettingsDialog::verifyFirmware()
 
 void EmuSettingsDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        closeDlg();
+        return;
+    }
+
     needsReset = false;
 
     if (r == QDialog::Accepted)

src/frontend/qt_sdl/FirmwareSettingsDialog.cpp

@@ -132,6 +132,13 @@ bool FirmwareSettingsDialog::verifyMAC()
 
 void FirmwareSettingsDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        closeDlg();
+        return;
+    }
+
     needsReset = false;
 
     if (r == QDialog::Accepted)

src/frontend/qt_sdl/InterfaceSettingsDialog.cpp

@@ -104,6 +104,13 @@ void InterfaceSettingsDialog::on_pbQuarter_clicked()
 
 void InterfaceSettingsDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        closeDlg();
+        return;
+    }
+
     if (r == QDialog::Accepted)
     {
         auto& cfg = emuInstance->getGlobalConfig();

src/frontend/qt_sdl/LANDialog.cpp

@@ -65,6 +65,12 @@ LANStartHostDialog::~LANStartHostDialog()
 
 void LANStartHostDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        return;
+    }
+
     if (r == QDialog::Accepted)
     {
         if (ui->txtPlayerName->text().trimmed().isEmpty())
@@ -186,6 +192,12 @@ void LANStartClientDialog::onDirectConnect()
 
 void LANStartClientDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        return;
+    }
+
     if (r == QDialog::Accepted)
     {
         if (ui->txtPlayerName->text().trimmed().isEmpty())
@@ -313,6 +325,12 @@ void LANDialog::on_btnLeaveGame_clicked()
 
 void LANDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        return;
+    }
+
     bool showwarning = true;
     if (lan().GetNumPlayers() < 2)
         showwarning = false;

src/frontend/qt_sdl/MPSettingsDialog.cpp

@@ -59,6 +59,13 @@ MPSettingsDialog::~MPSettingsDialog()
 
 void MPSettingsDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        closeDlg();
+        return;
+    }
+
     if (r == QDialog::Accepted)
     {
         auto& cfg = emuInstance->getGlobalConfig();

src/frontend/qt_sdl/NetplayDialog.cpp

@@ -63,6 +63,12 @@ NetplayStartHostDialog::~NetplayStartHostDialog()
 
 void NetplayStartHostDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        return;
+    }
+
     if (r == QDialog::Accepted)
     {
         std::string player = ui->txtPlayerName->text().toStdString();
@@ -94,6 +100,12 @@ NetplayStartClientDialog::~NetplayStartClientDialog()
 
 void NetplayStartClientDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        return;
+    }
+
     if (r == QDialog::Accepted)
     {
         std::string player = ui->txtPlayerName->text().toStdString();

src/frontend/qt_sdl/PathSettingsDialog.cpp

@@ -72,6 +72,13 @@ PathSettingsDialog::~PathSettingsDialog()
 
 void PathSettingsDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        closeDlg();
+        return;
+    }
+    
     needsReset = false;
 
     if (r == QDialog::Accepted)

src/frontend/qt_sdl/VideoSettingsDialog.cpp

@@ -121,6 +121,12 @@ void VideoSettingsDialog::on_VideoSettingsDialog_accepted()
 
 void VideoSettingsDialog::on_VideoSettingsDialog_rejected()
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        closeDlg();
+        return;
+    }
+
     bool old_gl = UsesGL();
 
     auto& cfg = emuInstance->getGlobalConfig();

src/frontend/qt_sdl/WifiSettingsDialog.cpp

@@ -94,6 +94,13 @@ WifiSettingsDialog::~WifiSettingsDialog()
 
 void WifiSettingsDialog::done(int r)
 {
+    if (!((MainWindow*)parent())->getEmuInstance())
+    {
+        QDialog::done(r);
+        closeDlg();
+        return;
+    }
+
     needsReset = false;
 
     if (r == QDialog::Accepted)