Cleanup related fixes

Signed-off-by: falkTX <falktx@falktx.com>

src/CardinalPlugin.cpp

@@ -52,6 +52,7 @@
 static const constexpr uint kCardinalStateBaseCount = 3; // patch, screenshot, comment
 
 #ifndef HEADLESS
+# include "extra/ScopedValueSetter.hpp"
 # include "WindowParameters.hpp"
 static const constexpr uint kCardinalStateCount = kCardinalStateBaseCount + 2; // moduleInfos, windowSize
 #else
@@ -68,6 +69,9 @@ static const constexpr uint kCardinalStateCount = kCardinalStateBaseCount;
 #endif
 
 namespace rack {
+namespace engine {
+    void Engine_setAboutToClose(Engine*);
+}
 namespace plugin {
     void initStaticPlugins();
     void destroyStaticPlugins();
@@ -572,6 +576,12 @@ public:
         {
             const ScopedContext sc(this);
             context->patch->clear();
+
+            // do a little dance to prevent context scene deletion from saving to temp dir
+#ifndef HEADLESS
+            const ScopedValueSetter<bool> svs(rack::settings::headless, true);
+#endif
+            Engine_setAboutToClose(context->engine);
             delete context;
         }
 

src/extra/ScopedValueSetter.hpp

@@ -0,0 +1,90 @@
+/*
+ * Scope value setter, taken from JUCE v4
+ * Copyright (C) 2013 Raw Material Software Ltd.
+ * Copyright (c) 2016 ROLI Ltd.
+ * Copyright (C) 2013-2020 Filipe Coelho <falktx@falktx.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 2 of
+ * the License, or 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.
+ *
+ * For a full copy of the GNU General Public License see the doc/GPL.txt file.
+ */
+
+#pragma once
+
+#include "DistrhoUtils.hpp"
+
+START_NAMESPACE_DISTRHO
+
+//=====================================================================================================================
+/**
+    Helper class providing an RAII-based mechanism for temporarily setting and
+    then re-setting a value.
+
+    E.g. @code
+    int x = 1;
+
+    {
+        ScopedValueSetter setter (x, 2);
+
+        // x is now 2
+    }
+
+    // x is now 1 again
+
+    {
+        ScopedValueSetter setter (x, 3, 4);
+
+        // x is now 3
+    }
+
+    // x is now 4
+    @endcode
+*/
+template <typename ValueType>
+class ScopedValueSetter
+{
+public:
+    /** Creates a ScopedValueSetter that will immediately change the specified value to the
+        given new value, and will then reset it to its original value when this object is deleted.
+        Must be used only for 'noexcept' compatible types.
+    */
+    ScopedValueSetter(ValueType& valueToSet, ValueType newValue) noexcept
+        : value(valueToSet),
+          originalValue(valueToSet)
+    {
+        valueToSet = newValue;
+    }
+
+    /** Creates a ScopedValueSetter that will immediately change the specified value to the
+        given new value, and will then reset it to be valueWhenDeleted when this object is deleted.
+    */
+    ScopedValueSetter(ValueType& valueToSet, ValueType newValue, ValueType valueWhenDeleted) noexcept
+        : value(valueToSet),
+          originalValue(valueWhenDeleted)
+    {
+        valueToSet = newValue;
+    }
+
+    ~ScopedValueSetter() noexcept
+    {
+        value = originalValue;
+    }
+
+private:
+    //=================================================================================================================
+    ValueType& value;
+    const ValueType originalValue;
+
+    DISTRHO_DECLARE_NON_COPYABLE(ScopedValueSetter)
+    DISTRHO_PREVENT_HEAP_ALLOCATION
+};
+
+END_NAMESPACE_DISTRHO

src/override/Engine.cpp

@@ -79,6 +79,7 @@ struct Engine::Internal {
 	int64_t blockFrame = 0;
 	double blockTime = 0.0;
 	int blockFrames = 0;
+	bool aboutToClose = false;
 
 #ifndef HEADLESS
 	// Meter
@@ -776,6 +777,8 @@ void Engine::prepareSaveModule(Module* module) {
 
 
 void Engine::prepareSave() {
+	if (internal->aboutToClose)
+		return;
 	SharedLock<SharedMutex> lock(internal->mutex);
 	for (Module* module : internal->modules) {
 		Module::SaveEvent e;
@@ -1175,5 +1178,10 @@ void Engine::startFallbackThread() {
 }
 
 
+void Engine_setAboutToClose(Engine* const engine) {
+	engine->internal->aboutToClose = true;
+}
+
+
 } // namespace engine
 } // namespace rack