Fix crash: Processor owns scan thread + results, Editor just reads them

Source/PluginBridgeProcessor.cpp

@@ -1,5 +1,6 @@
 #include "PluginBridgeProcessor.h"
 #include "PluginBridgeEditor.h"
+#include <thread>
 
 PluginBridgeProcessor::PluginBridgeProcessor()
     : AudioProcessor(BusesProperties()
@@ -30,13 +31,11 @@ void PluginBridgeProcessor::processBlock(juce::AudioBuffer<float>& buffer,
 {
     juce::ScopedNoDenormals noDenormals;
 
-    // Clear extra output channels
     auto totalNumInputChannels = getTotalNumInputChannels();
     auto totalNumOutputChannels = getTotalNumOutputChannels();
     for (auto i = totalNumInputChannels; i < totalNumOutputChannels; ++i)
         buffer.clear(i, 0, buffer.getNumSamples());
 
-    // Route audio through hosted plugin
     hostManager.processBlock(buffer, midiMessages);
 }
 
@@ -47,7 +46,6 @@ juce::AudioProcessorEditor* PluginBridgeProcessor::createEditor()
 
 void PluginBridgeProcessor::getStateInformation(juce::MemoryBlock& destData)
 {
-    // Save the path of the hosted plugin so it reloads on session restore
     juce::ValueTree state("PluginBridgeState");
     state.setProperty("hostedPluginPath", hostManager.getLoadedPluginPath(), nullptr);
 
@@ -85,6 +83,52 @@ void PluginBridgeProcessor::loadPluginFromFile(const juce::File& file)
     hostManager.loadPlugin(file, getSampleRate(), getBlockSize());
 }
 
+void PluginBridgeProcessor::startPluginScan()
+{
+    if (scanning.load() || scanComplete.load())
+        return;
+
+    scanning.store(true);
+
+    // Detached thread is safe here because Processor outlives Editor
+    // and scannedPlugins is only written by this thread, read by message thread after scanComplete=true
+    std::thread([this]()
+    {
+        juce::AudioPluginFormatManager formatManager;
+        #if JUCE_PLUGINHOST_VST3
+        formatManager.addFormat(new juce::VST3PluginFormat());
+        #endif
+        #if JUCE_PLUGINHOST_AU
+        formatManager.addFormat(new juce::AudioUnitPluginFormat());
+        #endif
+
+        juce::KnownPluginList pluginList;
+
+        for (int i = 0; i < formatManager.getNumFormats(); ++i)
+        {
+            auto* format = formatManager.getFormat(i);
+            auto searchPaths = format->getDefaultLocationsToSearch();
+
+            juce::PluginDirectoryScanner scanner(
+                pluginList,
+                *format,
+                searchPaths,
+                true,
+                juce::File()
+            );
+
+            juce::String pluginName;
+            while (scanner.scanNextFile(false, pluginName)) {}
+        }
+
+        // Copy results (safe — Editor only reads after scanComplete is true)
+        scannedPlugins = pluginList.getTypes();
+        scanning.store(false);
+        scanComplete.store(true);
+
+    }).detach();
+}
+
 // JUCE plugin entry point
 juce::AudioProcessor* JUCE_CALLTYPE createPluginFilter()
 {