Change the way plugins are deleted, ensure they are not being used

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

source/backend/CarlaEngine.hpp

@@ -20,6 +20,8 @@
 
 #include "CarlaBackend.h"
 
+#include <memory>
+
 namespace water {
 class MemoryOutputStream;
 class XmlDocument;
@@ -27,6 +29,8 @@ class XmlDocument;
 
 CARLA_BACKEND_START_NAMESPACE
 
+typedef std::shared_ptr<CarlaPlugin> CarlaPluginPtr;
+
 // -----------------------------------------------------------------------
 
 /*!
@@ -704,7 +708,7 @@ public:
      * Deactivate this client.
      * Client must be activated before calling this function.
      */
-    virtual void deactivate() noexcept;
+    virtual void deactivate(bool willClose) noexcept;
 
     /*!
      * Check if the client is activated.
@@ -925,7 +929,7 @@ public:
      * Add new engine client.
      * @note This function must only be called within a plugin class.
      */
-    virtual CarlaEngineClient* addClient(CarlaPlugin* plugin);
+    virtual CarlaEngineClient* addClient(CarlaPluginPtr plugin);
 
     /*!
      * Get the current CPU load estimated by the engine.
@@ -1024,12 +1028,12 @@ public:
     /*!
      * Get plugin with id @a id.
      */
-    CarlaPlugin* getPlugin(uint id) const noexcept;
+    CarlaPluginPtr getPlugin(uint id) const noexcept;
 
     /*!
      * Get plugin with id @a id, faster unchecked version.
      */
-    CarlaPlugin* getPluginUnchecked(uint id) const noexcept;
+    CarlaPluginPtr getPluginUnchecked(uint id) const noexcept;
 
     /*!
      * Get a unique plugin name within the engine.

source/backend/CarlaPlugin.hpp

@@ -1,6 +1,6 @@
 /*
  * Carla Plugin Host
- * Copyright (C) 2011-2019 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2011-2020 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
@@ -20,6 +20,8 @@
 
 #include "CarlaBackend.h"
 
+#include <memory>
+
 // -----------------------------------------------------------------------
 // Avoid including extra libs here
 
@@ -35,6 +37,8 @@ CARLA_BACKEND_START_NAMESPACE
 } /* Fix editor indentation */
 #endif
 
+typedef std::shared_ptr<CarlaPlugin> CarlaPluginPtr;
+
 // -----------------------------------------------------------------------
 
 /*!
@@ -943,21 +947,22 @@ public:
         const uint options; // see PluginOptions
     };
 
-    static CarlaPlugin* newNative(const Initializer& init);
-    static CarlaPlugin* newBridge(const Initializer& init, BinaryType btype, PluginType ptype, const char* bridgeBinary);
+    static CarlaPluginPtr newNative(const Initializer& init);
+    static CarlaPluginPtr newBridge(const Initializer& init,
+                                                  BinaryType btype, PluginType ptype, const char* bridgeBinary);
 
-    static CarlaPlugin* newLADSPA(const Initializer& init, const LADSPA_RDF_Descriptor* rdfDescriptor);
-    static CarlaPlugin* newDSSI(const Initializer& init);
-    static CarlaPlugin* newLV2(const Initializer& init);
-    static CarlaPlugin* newVST2(const Initializer& init);
-    static CarlaPlugin* newVST3(const Initializer& init);
-    static CarlaPlugin* newAU(const Initializer& init);
+    static CarlaPluginPtr newLADSPA(const Initializer& init, const LADSPA_RDF_Descriptor* rdfDescriptor);
+    static CarlaPluginPtr newDSSI(const Initializer& init);
+    static CarlaPluginPtr newLV2(const Initializer& init);
+    static CarlaPluginPtr newVST2(const Initializer& init);
+    static CarlaPluginPtr newVST3(const Initializer& init);
+    static CarlaPluginPtr newAU(const Initializer& init);
 
-    static CarlaPlugin* newJuce(const Initializer& init, const char* format);
-    static CarlaPlugin* newFluidSynth(const Initializer& init, PluginType ptype, bool use16Outs);
-    static CarlaPlugin* newSFZero(const Initializer& init);
+    static CarlaPluginPtr newJuce(const Initializer& init, const char* format);
+    static CarlaPluginPtr newFluidSynth(const Initializer& init, PluginType ptype, bool use16Outs);
+    static CarlaPluginPtr newSFZero(const Initializer& init);
 
-    static CarlaPlugin* newJackApp(const Initializer& init);
+    static CarlaPluginPtr newJackApp(const Initializer& init);
 #endif
 
     // -------------------------------------------------------------------
@@ -980,6 +985,11 @@ public:
     virtual void restoreLV2State() noexcept;
 
 protected:
+    /*!
+     * Allow engine to signal that plugin will be deleted soon.
+     */
+    virtual void prepareForDeletion() noexcept;
+
     /*!
      * Give plugin bridges a change to update their custom data sets.
      */
@@ -1025,6 +1035,7 @@ protected:
         CARLA_DECLARE_NON_COPY_CLASS(ScopedSingleProcessLocker)
     };
 
+    friend class CarlaEngine;
     friend class CarlaEngineBridge;
     CARLA_DECLARE_NON_COPY_CLASS(CarlaPlugin)
 };

source/backend/CarlaStandalone.cpp

@@ -58,6 +58,10 @@ static void carla_juce_cleanup();
 
 // --------------------------------------------------------------------------------------------------------------------
 
+using CarlaBackend::CarlaPluginPtr;
+
+// --------------------------------------------------------------------------------------------------------------------
+
 uint carla_get_engine_driver_count()
 {
     carla_debug("carla_get_engine_driver_count()");
@@ -1166,7 +1170,7 @@ bool carla_load_plugin_state(CarlaHostHandle handle, uint pluginId, const char*
     CARLA_SAFE_ASSERT_WITH_LAST_ERROR_RETURN(handle->engine != nullptr
                                           && handle->engine->isRunning(), "Engine is not running", false);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_WITH_LAST_ERROR_RETURN(plugin != nullptr, "could not find requested plugin", false);
 
     carla_debug("carla_load_plugin_state(%p, %i, \"%s\")", handle, pluginId, filename);
@@ -1179,7 +1183,7 @@ bool carla_save_plugin_state(CarlaHostHandle handle, uint pluginId, const char*
     CARLA_SAFE_ASSERT_RETURN(filename != nullptr && filename[0] != '\0', false);
     CARLA_SAFE_ASSERT_WITH_LAST_ERROR_RETURN(handle->engine != nullptr, "Engine is not initialized", false);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_WITH_LAST_ERROR_RETURN(plugin != nullptr, "could not find requested plugin", false);
 
     carla_debug("carla_save_plugin_state(%p, %i, \"%s\")", handle, pluginId, filename);
@@ -1192,7 +1196,7 @@ bool carla_export_plugin_lv2(CarlaHostHandle handle, uint pluginId, const char*
     CARLA_SAFE_ASSERT_RETURN(lv2path != nullptr && lv2path[0] != '\0', false);
     CARLA_SAFE_ASSERT_WITH_LAST_ERROR_RETURN(handle->engine != nullptr, "Engine is not initialized", false);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_WITH_LAST_ERROR_RETURN(plugin != nullptr, "could not find requested plugin", false);
 
     carla_debug("carla_export_plugin_lv2(%p, %i, \"%s\")", handle, pluginId, lv2path);
@@ -1238,7 +1242,7 @@ const CarlaPluginInfo* carla_get_plugin_info(CarlaHostHandle handle, uint plugin
 
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, &retInfo);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, &retInfo);
 
     carla_debug("carla_get_plugin_info(%p, %i)", handle, pluginId);
@@ -1281,7 +1285,7 @@ const CarlaPortCountInfo* carla_get_audio_port_count_info(CarlaHostHandle handle
 
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, &retInfo);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, &retInfo);
 
     carla_debug("carla_get_audio_port_count_info(%p, %i)", handle, pluginId);
@@ -1298,7 +1302,7 @@ const CarlaPortCountInfo* carla_get_midi_port_count_info(CarlaHostHandle handle,
 
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, &retInfo);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, &retInfo);
 
     carla_debug("carla_get_midi_port_count_info(%p, %i)", handle, pluginId);
@@ -1315,7 +1319,7 @@ const CarlaPortCountInfo* carla_get_parameter_count_info(CarlaHostHandle handle,
 
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, &retInfo);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, &retInfo);
 
     carla_debug("carla_get_parameter_count_info(%p, %i)", handle, pluginId);
@@ -1364,7 +1368,7 @@ const CarlaParameterInfo* carla_get_parameter_info(CarlaHostHandle handle, uint
 
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, &retInfo);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, &retInfo);
 
     carla_debug("carla_get_parameter_info(%p, %i, %i)", handle, pluginId, parameterId);
@@ -1434,7 +1438,7 @@ const CarlaScalePointInfo* carla_get_parameter_scalepoint_info(CarlaHostHandle h
 
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, &retInfo);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, &retInfo);
 
     carla_debug("carla_get_parameter_scalepoint_info(%p, %i, %i, %i)", handle, pluginId, parameterId, scalePointId);
@@ -1470,7 +1474,7 @@ const ParameterData* carla_get_parameter_data(CarlaHostHandle handle, uint plugi
 
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, &retParamData);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, &retParamData);
 
     carla_debug("carla_get_parameter_data(%p, %i, %i)", handle, pluginId, parameterId);
@@ -1502,7 +1506,7 @@ const ParameterRanges* carla_get_parameter_ranges(CarlaHostHandle handle, uint p
 
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, &retParamRanges);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, &retParamRanges);
 
     carla_debug("carla_get_parameter_ranges(%p, %i, %i)", handle, pluginId, parameterId);
@@ -1534,7 +1538,7 @@ const MidiProgramData* carla_get_midi_program_data(CarlaHostHandle handle, uint
 
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, &retMidiProgData);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, &retMidiProgData);
 
     carla_debug("carla_get_midi_program_data(%p, %i, %i)", handle, pluginId, midiProgramId);
@@ -1582,7 +1586,7 @@ const CustomData* carla_get_custom_data(CarlaHostHandle handle, uint pluginId, u
 
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, &retCustomData);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, &retCustomData);
 
     carla_debug("carla_get_custom_data(%p, %i, %i)", handle, pluginId, customDataId);
@@ -1604,7 +1608,7 @@ const char* carla_get_custom_data_value(CarlaHostHandle handle, uint pluginId, c
     CARLA_SAFE_ASSERT_RETURN(key != nullptr && key[0] != '\0', gNullCharPtr);
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, gNullCharPtr);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, gNullCharPtr);
 
     carla_debug("carla_get_custom_data_value(%p, %i, %s, %s)", handle, pluginId, type, key);
@@ -1636,7 +1640,7 @@ const char* carla_get_chunk_data(CarlaHostHandle handle, uint pluginId)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, gNullCharPtr);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, gNullCharPtr);
 
     carla_debug("carla_get_chunk_data(%p, %i)", handle, pluginId);
@@ -1658,7 +1662,7 @@ uint32_t carla_get_parameter_count(CarlaHostHandle handle, uint pluginId)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, 0);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, 0);
 
     carla_debug("carla_get_parameter_count(%p, %i)", handle, pluginId);
@@ -1669,7 +1673,7 @@ uint32_t carla_get_program_count(CarlaHostHandle handle, uint pluginId)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, 0);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, 0);
 
     carla_debug("carla_get_program_count(%p, %i)", handle, pluginId);
@@ -1680,7 +1684,7 @@ uint32_t carla_get_midi_program_count(CarlaHostHandle handle, uint pluginId)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, 0);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, 0);
 
     carla_debug("carla_get_midi_program_count(%p, %i)", handle, pluginId);
@@ -1691,7 +1695,7 @@ uint32_t carla_get_custom_data_count(CarlaHostHandle handle, uint pluginId)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, 0);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, 0);
 
     carla_debug("carla_get_custom_data_count(%p, %i)", handle, pluginId);
@@ -1704,7 +1708,7 @@ const char* carla_get_parameter_text(CarlaHostHandle handle, uint pluginId, uint
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, gNullCharPtr);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, gNullCharPtr);
 
     carla_debug("carla_get_parameter_text(%p, %i, %i)", handle, pluginId, parameterId);
@@ -1723,7 +1727,7 @@ const char* carla_get_program_name(CarlaHostHandle handle, uint pluginId, uint32
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, nullptr);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, gNullCharPtr);
 
     carla_debug("carla_get_program_name(%p, %i, %i)", handle, pluginId, programId);
@@ -1742,7 +1746,7 @@ const char* carla_get_midi_program_name(CarlaHostHandle handle, uint pluginId, u
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, gNullCharPtr);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, gNullCharPtr);
 
     carla_debug("carla_get_midi_program_name(%p, %i, %i)", handle, pluginId, midiProgramId);
@@ -1761,7 +1765,7 @@ const char* carla_get_real_plugin_name(CarlaHostHandle handle, uint pluginId)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, gNullCharPtr);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, gNullCharPtr);
 
     carla_debug("carla_get_real_plugin_name(%p, %i)", handle, pluginId);
@@ -1780,7 +1784,7 @@ int32_t carla_get_current_program_index(CarlaHostHandle handle, uint pluginId)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, -1);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, -1);
 
     carla_debug("carla_get_current_program_index(%p, %i)", handle, pluginId);
@@ -1791,7 +1795,7 @@ int32_t carla_get_current_midi_program_index(CarlaHostHandle handle, uint plugin
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, -1);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, -1);
 
     carla_debug("carla_get_current_midi_program_index(%p, %i)", handle, pluginId);
@@ -1804,7 +1808,7 @@ float carla_get_default_parameter_value(CarlaHostHandle handle, uint pluginId, u
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, 0.0f);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, 0.0f);
 
     carla_debug("carla_get_default_parameter_value(%p, %i, %i)", handle, pluginId, parameterId);
@@ -1817,7 +1821,7 @@ float carla_get_current_parameter_value(CarlaHostHandle handle, uint pluginId, u
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr, 0.0f);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, 0.0f);
     CARLA_SAFE_ASSERT_RETURN(parameterId < plugin->getParameterCount(), 0.0f);
 
@@ -1833,7 +1837,7 @@ float carla_get_internal_parameter_value(CarlaHostHandle handle, uint pluginId,
 #endif
     CARLA_SAFE_ASSERT_RETURN(parameterId != CB::PARAMETER_NULL && parameterId > CB::PARAMETER_MAX, 0.0f);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, 0.0f);
 
     carla_debug("carla_get_internal_parameter_value(%p, %i, %i)", handle, pluginId, parameterId);
@@ -1869,11 +1873,11 @@ CARLA_BACKEND_START_NAMESPACE
 
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
 // defined in CarlaPluginInternal.cpp
-const void* carla_render_inline_display_internal(CarlaPlugin* plugin, uint32_t  width, uint32_t height);
+const void* carla_render_inline_display_internal(const CarlaPluginPtr& plugin, uint32_t width, uint32_t height);
 #endif
 
 // defined in CarlaPluginLV2.cpp
-const void* carla_render_inline_display_lv2(CarlaPlugin* plugin, uint32_t width, uint32_t height);
+const void* carla_render_inline_display_lv2(const CarlaPluginPtr& plugin, uint32_t width, uint32_t height);
 
 CARLA_BACKEND_END_NAMESPACE
 
@@ -1883,7 +1887,7 @@ const CarlaInlineDisplayImageSurface* carla_render_inline_display(CarlaHostHandl
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr && handle->engine->isRunning(), nullptr);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr, nullptr);
 
     carla_debug("carla_render_inline_display(%p, %i, %i, %i)", handle, pluginId, width, height);
@@ -1910,7 +1914,7 @@ void carla_set_active(CarlaHostHandle handle, uint pluginId, bool onOff)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_active(%p, %i, %s)", handle, pluginId, bool2str(onOff));
@@ -1922,7 +1926,7 @@ void carla_set_drywet(CarlaHostHandle handle, uint pluginId, float value)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_drywet(%p, %i, %f)", handle, pluginId, static_cast<double>(value));
@@ -1933,7 +1937,7 @@ void carla_set_volume(CarlaHostHandle handle, uint pluginId, float value)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_volume(%p, %i, %f)", handle, pluginId, static_cast<double>(value));
@@ -1944,7 +1948,7 @@ void carla_set_balance_left(CarlaHostHandle handle, uint pluginId, float value)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_balance_left(%p, %i, %f)", handle, pluginId, static_cast<double>(value));
@@ -1955,7 +1959,7 @@ void carla_set_balance_right(CarlaHostHandle handle, uint pluginId, float value)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_balance_right(%p, %i, %f)", handle, pluginId, static_cast<double>(value));
@@ -1966,7 +1970,7 @@ void carla_set_panning(CarlaHostHandle handle, uint pluginId, float value)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_panning(%p, %i, %f)", handle, pluginId, static_cast<double>(value));
@@ -1978,7 +1982,7 @@ void carla_set_ctrl_channel(CarlaHostHandle handle, uint pluginId, int8_t channe
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
     CARLA_SAFE_ASSERT_RETURN(channel >= -1 && channel < MAX_MIDI_CHANNELS,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_ctrl_channel(%p, %i, %i)", handle, pluginId, channel);
@@ -1990,7 +1994,7 @@ void carla_set_option(CarlaHostHandle handle, uint pluginId, uint option, bool y
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_option(%p, %i, %i, %s)", handle, pluginId, option, bool2str(yesNo));
@@ -2003,7 +2007,7 @@ void carla_set_parameter_value(CarlaHostHandle handle, uint pluginId, uint32_t p
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_parameter_value(%p, %i, %i, %f)", handle, pluginId, parameterId, static_cast<double>(value));
@@ -2019,7 +2023,7 @@ void carla_set_parameter_midi_channel(CarlaHostHandle handle, uint pluginId, uin
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
     CARLA_SAFE_ASSERT_RETURN(channel < MAX_MIDI_CHANNELS,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_parameter_midi_channel(%p, %i, %i, %i)", handle, pluginId, parameterId, channel);
@@ -2033,7 +2037,7 @@ void carla_set_parameter_mapped_control_index(CarlaHostHandle handle, uint plugi
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
     CARLA_SAFE_ASSERT_RETURN(index >= CB::CONTROL_INDEX_NONE && index <= CB::CONTROL_INDEX_MAX_ALLOWED,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_parameter_mapped_control_index(%p, %i, %i, %i)", handle, pluginId, parameterId, index);
@@ -2046,7 +2050,7 @@ void carla_set_parameter_mapped_range(CarlaHostHandle handle, uint pluginId, uin
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_parameter_mapped_range(%p, %i, %i, %f, %f)",
@@ -2071,7 +2075,7 @@ void carla_set_program(CarlaHostHandle handle, uint pluginId, uint32_t programId
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_program(%p, %i, %i)", handle, pluginId, programId);
@@ -2084,7 +2088,7 @@ void carla_set_midi_program(CarlaHostHandle handle, uint pluginId, uint32_t midi
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_midi_program(%p, %i, %i)", handle, pluginId, midiProgramId);
@@ -2102,7 +2106,7 @@ void carla_set_custom_data(CarlaHostHandle handle, uint pluginId, const char* ty
     CARLA_SAFE_ASSERT_RETURN(key != nullptr && key[0] != '\0',);
     CARLA_SAFE_ASSERT_RETURN(value != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_custom_data(%p, %i, \"%s\", \"%s\", \"%s\")", handle, pluginId, type, key, value);
@@ -2114,7 +2118,7 @@ void carla_set_chunk_data(CarlaHostHandle handle, uint pluginId, const char* chu
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
     CARLA_SAFE_ASSERT_RETURN(chunkData != nullptr && chunkData[0] != '\0',);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_set_chunk_data(%p, %i, \"%s\")", handle, pluginId, chunkData);
@@ -2134,7 +2138,7 @@ void carla_prepare_for_save(CarlaHostHandle handle, uint pluginId)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_prepare_for_save(%p, %i)", handle, pluginId);
@@ -2145,7 +2149,7 @@ void carla_reset_parameters(CarlaHostHandle handle, uint pluginId)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_reset_parameters(%p, %i)", handle, pluginId);
@@ -2156,7 +2160,7 @@ void carla_randomize_parameters(CarlaHostHandle handle, uint pluginId)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_randomize_parameters(%p, %i)", handle, pluginId);
@@ -2168,7 +2172,7 @@ void carla_send_midi_note(CarlaHostHandle handle, uint pluginId, uint8_t channel
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr && handle->engine->isRunning(),);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_send_midi_note(%p, %i, %i, %i, %i)", handle, pluginId, channel, note, velocity);
@@ -2181,7 +2185,7 @@ void carla_set_custom_ui_title_format(CarlaHostHandle handle, uint pluginId, con
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
     CARLA_SAFE_ASSERT_RETURN(format != nullptr && format[0] != '\0',);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_randomize_parameters(%p, %i, %s)", handle, pluginId, format);
@@ -2192,7 +2196,7 @@ void carla_show_custom_ui(CarlaHostHandle handle, uint pluginId, bool yesNo)
 {
     CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
 
-    CarlaPlugin* const plugin = handle->engine->getPlugin(pluginId);
+    const CarlaPluginPtr plugin = handle->engine->getPlugin(pluginId);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
     carla_debug("carla_show_custom_ui(%p, %i, %s)", handle, pluginId, bool2str(yesNo));

source/backend/engine/CarlaEngine.cpp

@@ -364,7 +364,7 @@ void CarlaEngine::idle() noexcept
 
     for (uint i=0; i < pData->curPluginCount; ++i)
     {
-        CarlaPlugin* const plugin(pData->plugins[i].plugin);
+        CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
         if (plugin != nullptr && plugin->isEnabled())
         {
@@ -382,9 +382,11 @@ void CarlaEngine::idle() noexcept
 #if defined(HAVE_LIBLO) && !defined(BUILD_BRIDGE)
     pData->osc.idle();
 #endif
+
+    pData->deletePluginsAsNeeded();
 }
 
-CarlaEngineClient* CarlaEngine::addClient(CarlaPlugin* const plugin)
+CarlaEngineClient* CarlaEngine::addClient(CarlaPluginPtr plugin)
 {
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
     return new CarlaEngineClientForStandalone(*this, pData->graph, plugin);
@@ -464,7 +466,7 @@ bool CarlaEngine::addPlugin(const BinaryType btype,
     uint id;
 
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
-    CarlaPlugin* oldPlugin = nullptr;
+    CarlaPluginPtr oldPlugin;
 
     if (pData->nextPluginId < pData->curPluginCount)
     {
@@ -501,7 +503,7 @@ bool CarlaEngine::addPlugin(const BinaryType btype,
         options
     };
 
-    CarlaPlugin* plugin = nullptr;
+    CarlaPluginPtr plugin;
     CarlaString bridgeBinary(pData->options.binaryDir);
 
     if (bridgeBinary.isNotEmpty())
@@ -670,7 +672,6 @@ bool CarlaEngine::addPlugin(const BinaryType btype,
 
     if (! canRun)
     {
-        delete plugin;
         return false;
     }
 
@@ -692,7 +693,8 @@ bool CarlaEngine::addPlugin(const BinaryType btype,
         const float oldDryWet = oldPlugin->getInternalParameterValue(PARAMETER_DRYWET);
         const float oldVolume = oldPlugin->getInternalParameterValue(PARAMETER_VOLUME);
 
-        delete oldPlugin;
+        oldPlugin->prepareForDeletion();
+        pData->pluginsToDelete.push_back(oldPlugin);
 
         if (plugin->getHints() & PLUGIN_CAN_DRYWET)
             plugin->setDryWet(oldDryWet, true, true);
@@ -741,12 +743,14 @@ bool CarlaEngine::removePlugin(const uint id)
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
     CARLA_SAFE_ASSERT_RETURN_ERR(pData->plugins != nullptr, "Invalid engine internal data");
     CARLA_SAFE_ASSERT_RETURN_ERR(pData->curPluginCount != 0, "Invalid engine internal data");
+#else
+    CARLA_SAFE_ASSERT_RETURN_ERR(id == 0, "Invalid engine internal data");
 #endif
     CARLA_SAFE_ASSERT_RETURN_ERR(pData->nextAction.opcode == kEnginePostActionNull, "Invalid engine internal data");
     CARLA_SAFE_ASSERT_RETURN_ERR(id < pData->curPluginCount, "Invalid plugin Id");
     carla_debug("CarlaEngine::removePlugin(%i)", id);
 
-    CarlaPlugin* const plugin(pData->plugins[id].plugin);
+    CarlaPluginPtr plugin = pData->plugins[id].plugin;
 
     CARLA_SAFE_ASSERT_RETURN_ERR(plugin != nullptr, "Could not find plugin to remove");
     CARLA_SAFE_ASSERT_RETURN_ERR(plugin->getId() == id, "Invalid engine internal data");
@@ -769,10 +773,12 @@ bool CarlaEngine::removePlugin(const uint id)
     */
 #else
     pData->curPluginCount = 0;
-    carla_zeroStructs(pData->plugins, 1);
+    pData->plugins[0].plugin = nullptr;
+    carla_zeroStruct(pData->plugins[0].peaks);
 #endif
 
-    delete plugin;
+    plugin->prepareForDeletion();
+    pData->pluginsToDelete.push_back(plugin);
 
     callback(true, true, ENGINE_CALLBACK_PLUGIN_REMOVED, id, 0, 0, 0, 0.0f, nullptr);
     return true;
@@ -793,7 +799,7 @@ bool CarlaEngine::removeAllPlugins()
 
     const ScopedThreadStopper sts(this);
 
-    const uint curPluginCount(pData->curPluginCount);
+    const uint curPluginCount = pData->curPluginCount;
 
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
     if (pData->options.processMode == ENGINE_PROCESS_MODE_PATCHBAY)
@@ -809,13 +815,11 @@ bool CarlaEngine::removeAllPlugins()
         const uint id = curPluginCount - i - 1;
         EnginePluginData& pluginData(pData->plugins[id]);
 
-        if (pluginData.plugin != nullptr)
-        {
-            delete pluginData.plugin;
-            pluginData.plugin = nullptr;
-        }
+        pluginData.plugin->prepareForDeletion();
+        pData->pluginsToDelete.push_back(pluginData.plugin);
 
-        carla_zeroFloats(pluginData.peaks, 4);
+        pluginData.plugin = nullptr;
+        carla_zeroStruct(pluginData.peaks);
 
         callback(true, true, ENGINE_CALLBACK_PLUGIN_REMOVED, id, 0, 0, 0, 0.0f, nullptr);
         callback(true, false, ENGINE_CALLBACK_IDLE, 0, 0, 0, 0, 0.0f, nullptr);
@@ -835,7 +839,7 @@ bool CarlaEngine::renamePlugin(const uint id, const char* const newName)
     CARLA_SAFE_ASSERT_RETURN_ERR(newName != nullptr && newName[0] != '\0', "Invalid plugin name");
     carla_debug("CarlaEngine::renamePlugin(%i, \"%s\")", id, newName);
 
-    CarlaPlugin* const plugin(pData->plugins[id].plugin);
+    CarlaPluginPtr plugin = pData->plugins[id].plugin;
     CARLA_SAFE_ASSERT_RETURN_ERR(plugin != nullptr, "Could not find plugin to rename");
     CARLA_SAFE_ASSERT_RETURN_ERR(plugin->getId() == id, "Invalid engine internal data");
 
@@ -862,7 +866,7 @@ bool CarlaEngine::clonePlugin(const uint id)
     CARLA_SAFE_ASSERT_RETURN_ERR(id < pData->curPluginCount, "Invalid plugin Id");
     carla_debug("CarlaEngine::clonePlugin(%i)", id);
 
-    CarlaPlugin* const plugin(pData->plugins[id].plugin);
+    CarlaPluginPtr plugin = pData->plugins[id].plugin;
 
     CARLA_SAFE_ASSERT_RETURN_ERR(plugin != nullptr, "Could not find plugin to clone");
     CARLA_SAFE_ASSERT_RETURN_ERR(plugin->getId() == id, "Invalid engine internal data");
@@ -882,7 +886,7 @@ bool CarlaEngine::clonePlugin(const uint id)
 
     CARLA_SAFE_ASSERT_RETURN_ERR(pluginCountBefore+1 == pData->curPluginCount, "No new plugin found");
 
-    if (CarlaPlugin* const newPlugin = pData->plugins[pluginCountBefore].plugin)
+    if (const CarlaPluginPtr newPlugin = pData->plugins[pluginCountBefore].plugin)
         newPlugin->loadStateSave(plugin->getStateSave());
 
     return true;
@@ -905,7 +909,7 @@ bool CarlaEngine::replacePlugin(const uint id) noexcept
 
     CARLA_SAFE_ASSERT_RETURN_ERR(id < pData->curPluginCount, "Invalid plugin Id");
 
-    CarlaPlugin* const plugin(pData->plugins[id].plugin);
+    CarlaPluginPtr plugin = pData->plugins[id].plugin;
 
     CARLA_SAFE_ASSERT_RETURN_ERR(plugin != nullptr, "Could not find plugin to replace");
     CARLA_SAFE_ASSERT_RETURN_ERR(plugin->getId() == id, "Invalid engine internal data");
@@ -926,8 +930,8 @@ bool CarlaEngine::switchPlugins(const uint idA, const uint idB) noexcept
     CARLA_SAFE_ASSERT_RETURN_ERR(idB < pData->curPluginCount, "Invalid plugin Id");
     carla_debug("CarlaEngine::switchPlugins(%i)", idA, idB);
 
-    CarlaPlugin* const pluginA(pData->plugins[idA].plugin);
-    CarlaPlugin* const pluginB(pData->plugins[idB].plugin);
+    CarlaPluginPtr pluginA = pData->plugins[idA].plugin;
+    CarlaPluginPtr pluginB = pData->plugins[idB].plugin;
 
     CARLA_SAFE_ASSERT_RETURN_ERR(pluginA != nullptr, "Could not find plugin to switch");
     CARLA_SAFE_ASSERT_RETURN_ERR(pluginA != nullptr, "Could not find plugin to switch");
@@ -958,7 +962,7 @@ void CarlaEngine::touchPluginParameter(const uint, const uint32_t, const bool) n
 {
 }
 
-CarlaPlugin* CarlaEngine::getPlugin(const uint id) const noexcept
+CarlaPluginPtr CarlaEngine::getPlugin(const uint id) const noexcept
 {
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
     CARLA_SAFE_ASSERT_RETURN_ERRN(pData->plugins != nullptr, "Invalid engine internal data");
@@ -970,7 +974,7 @@ CarlaPlugin* CarlaEngine::getPlugin(const uint id) const noexcept
     return pData->plugins[id].plugin;
 }
 
-CarlaPlugin* CarlaEngine::getPluginUnchecked(const uint id) const noexcept
+CarlaPluginPtr CarlaEngine::getPluginUnchecked(const uint id) const noexcept
 {
     return pData->plugins[id].plugin;
 }
@@ -1150,7 +1154,7 @@ bool CarlaEngine::loadFile(const char* const filename)
     {
         if (addPlugin(PLUGIN_INTERNAL, nullptr, baseName, "audiofile", 0, nullptr))
         {
-            if (CarlaPlugin* const plugin = getPlugin(curPluginId))
+            if (const CarlaPluginPtr plugin = getPlugin(curPluginId))
                 plugin->setCustomData(CUSTOM_DATA_TYPE_STRING, "file", filename, true);
             return true;
         }
@@ -1163,7 +1167,7 @@ bool CarlaEngine::loadFile(const char* const filename)
     {
         if (addPlugin(PLUGIN_INTERNAL, nullptr, baseName, "midifile", 0, nullptr))
         {
-            if (CarlaPlugin* const plugin = getPlugin(curPluginId))
+            if (const CarlaPluginPtr plugin = getPlugin(curPluginId))
                 plugin->setCustomData(CUSTOM_DATA_TYPE_STRING, "file", filename, true);
             return true;
         }
@@ -1185,13 +1189,16 @@ bool CarlaEngine::loadFile(const char* const filename)
         else
             nicerName += baseName;
 
-        //nicerName
         if (addPlugin(PLUGIN_INTERNAL, nullptr, nicerName, "zynaddsubfx", 0, nullptr))
         {
             callback(true, true, ENGINE_CALLBACK_UI_STATE_CHANGED, curPluginId, 0, 0, 0, 0.0f, nullptr);
 
-            if (CarlaPlugin* const plugin = getPlugin(curPluginId))
-                plugin->setCustomData(CUSTOM_DATA_TYPE_STRING, (extension == "xmz") ? "CarlaAlternateFile1" : "CarlaAlternateFile2", filename, true);
+            if (const CarlaPluginPtr plugin = getPlugin(curPluginId))
+            {
+                const char* const ext = (extension == "xmz") ? "CarlaAlternateFile1" : "CarlaAlternateFile2";
+                plugin->setCustomData(CUSTOM_DATA_TYPE_STRING, ext, filename, true);
+            }
+
             return true;
         }
         return false;
@@ -1415,7 +1422,7 @@ void CarlaEngine::callback(const bool sendHost, const bool sendOSC,
             {
             case ENGINE_CALLBACK_RELOAD_INFO:
             {
-                CarlaPlugin* const plugin = pData->plugins[pluginId].plugin;
+                CarlaPluginPtr plugin = pData->plugins[pluginId].plugin;
                 CARLA_SAFE_ASSERT_BREAK(plugin != nullptr);
 
                 pData->osc.sendPluginInfo(plugin);
@@ -1424,7 +1431,7 @@ void CarlaEngine::callback(const bool sendHost, const bool sendOSC,
 
             case ENGINE_CALLBACK_RELOAD_PARAMETERS:
             {
-                CarlaPlugin* const plugin = pData->plugins[pluginId].plugin;
+                CarlaPluginPtr plugin = pData->plugins[pluginId].plugin;
                 CARLA_SAFE_ASSERT_BREAK(plugin != nullptr);
 
                 pData->osc.sendPluginPortCount(plugin);
@@ -1439,7 +1446,7 @@ void CarlaEngine::callback(const bool sendHost, const bool sendOSC,
 
             case ENGINE_CALLBACK_RELOAD_PROGRAMS:
             {
-                CarlaPlugin* const plugin = pData->plugins[pluginId].plugin;
+                CarlaPluginPtr plugin = pData->plugins[pluginId].plugin;
                 CARLA_SAFE_ASSERT_BREAK(plugin != nullptr);
 
                 pData->osc.sendPluginProgramCount(plugin);
@@ -1461,7 +1468,7 @@ void CarlaEngine::callback(const bool sendHost, const bool sendOSC,
             case ENGINE_CALLBACK_PLUGIN_ADDED:
             case ENGINE_CALLBACK_RELOAD_ALL:
             {
-                CarlaPlugin* const plugin = pData->plugins[pluginId].plugin;
+                CarlaPluginPtr plugin = pData->plugins[pluginId].plugin;
                 CARLA_SAFE_ASSERT_BREAK(plugin != nullptr);
 
                 pData->osc.sendPluginInfo(plugin);
@@ -2023,7 +2030,7 @@ void CarlaEngine::bufferSizeChanged(const uint32_t newBufferSize)
 
     for (uint i=0; i < pData->curPluginCount; ++i)
     {
-        CarlaPlugin* const plugin(pData->plugins[i].plugin);
+        CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
         if (plugin != nullptr && plugin->isEnabled())
         {
@@ -2052,7 +2059,7 @@ void CarlaEngine::sampleRateChanged(const double newSampleRate)
 
     for (uint i=0; i < pData->curPluginCount; ++i)
     {
-        CarlaPlugin* const plugin(pData->plugins[i].plugin);
+        CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
         if (plugin != nullptr && plugin->isEnabled())
         {
@@ -2079,7 +2086,7 @@ void CarlaEngine::offlineModeChanged(const bool isOfflineNow)
 
     for (uint i=0; i < pData->curPluginCount; ++i)
     {
-        CarlaPlugin* const plugin(pData->plugins[i].plugin);
+        CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
         if (plugin != nullptr && plugin->isEnabled())
             plugin->offlineModeChanged(isOfflineNow);
@@ -2101,7 +2108,7 @@ void CarlaEngine::saveProjectInternal(water::MemoryOutputStream& outStream) cons
     // send initial prepareForSave first, giving time for bridges to act
     for (uint i=0; i < pData->curPluginCount; ++i)
     {
-        CarlaPlugin* const plugin(pData->plugins[i].plugin);
+        CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
         if (plugin != nullptr && plugin->isEnabled())
         {
@@ -2165,7 +2172,7 @@ void CarlaEngine::saveProjectInternal(water::MemoryOutputStream& outStream) cons
 
     for (uint i=0; i < pData->curPluginCount; ++i)
     {
-        CarlaPlugin* const plugin(pData->plugins[i].plugin);
+        CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
         if (plugin != nullptr && plugin->isEnabled())
         {
@@ -2188,7 +2195,7 @@ void CarlaEngine::saveProjectInternal(water::MemoryOutputStream& outStream) cons
     // tell bridges we're done saving
     for (uint i=0; i < pData->curPluginCount; ++i)
     {
-        CarlaPlugin* const plugin(pData->plugins[i].plugin);
+        CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
         if (plugin != nullptr && plugin->isEnabled() && (plugin->getHints() & PLUGIN_IS_BRIDGE) != 0)
             plugin->setCustomData(CUSTOM_DATA_TYPE_STRING, "__CarlaPingOnOff__", "true", false);
@@ -2639,7 +2646,7 @@ bool CarlaEngine::loadProjectInternal(water::XmlDocument& xmlDoc)
                 {
                     const uint pluginId = pData->curPluginCount;
 
-                    if (CarlaPlugin* const plugin = pData->plugins[pluginId].plugin)
+                    if (const CarlaPluginPtr plugin = pData->plugins[pluginId].plugin)
                     {
                         callback(true, true, ENGINE_CALLBACK_IDLE, 0, 0, 0, 0, 0.0f, nullptr);
 
@@ -2789,7 +2796,7 @@ bool CarlaEngine::loadProjectInternal(water::XmlDocument& xmlDoc)
                 const uint pluginId = 0;
 #endif
 
-                if (CarlaPlugin* const plugin = pData->plugins[pluginId].plugin)
+                if (const CarlaPluginPtr plugin = pData->plugins[pluginId].plugin)
                 {
                     callback(true, true, ENGINE_CALLBACK_IDLE, 0, 0, 0, 0, 0.0f, nullptr);
 
@@ -2845,7 +2852,7 @@ bool CarlaEngine::loadProjectInternal(water::XmlDocument& xmlDoc)
     // tell bridges we're done loading
     for (uint i=0; i < pData->curPluginCount; ++i)
     {
-        CarlaPlugin* const plugin(pData->plugins[i].plugin);
+        CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
         if (plugin != nullptr && plugin->isEnabled() && (plugin->getHints() & PLUGIN_IS_BRIDGE) != 0)
             plugin->setCustomData(CUSTOM_DATA_TYPE_STRING, "__CarlaPingOnOff__", "true", false);

source/backend/engine/CarlaEngineBridge.cpp

@@ -67,7 +67,10 @@ class CarlaEngineBridgeClient : public CarlaEngineClientForSubclassing
 {
 public:
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
-    CarlaEngineBridgeClient(const CarlaEngine& engine, EngineInternalGraph& egraph, CarlaPlugin* const plugin, LatencyChangedCallback* const cb)
+    CarlaEngineBridgeClient(const CarlaEngine& engine,
+                            EngineInternalGraph& egraph,
+                            const CarlaPluginPtr plugin,
+                            LatencyChangedCallback* const cb)
         : CarlaEngineClientForSubclassing(engine, egraph, plugin),
           fLatencyCallback(cb) {}
 #else
@@ -294,7 +297,7 @@ public:
         fShmNonRtServerControl.commitWrite();
     }
 
-    CarlaEngineClient* addClient(CarlaPlugin* const plugin) override
+    CarlaEngineClient* addClient(const CarlaPluginPtr plugin) override
     {
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
         return new CarlaEngineBridgeClient(*this, pData->graph, plugin, this);
@@ -308,7 +311,7 @@ public:
 
     void idle() noexcept override
     {
-        CarlaPlugin* const plugin(pData->plugins[0].plugin);
+        const CarlaPluginPtr plugin = pData->plugins[0].plugin;
 
         if (plugin == nullptr)
         {
@@ -702,7 +705,7 @@ public:
             break;
 
         case ENGINE_CALLBACK_RELOAD_PARAMETERS:
-            if (CarlaPlugin* const plugin = pData->plugins[0].plugin)
+            if (const CarlaPluginPtr plugin = pData->plugins[0].plugin)
             {
                 if (const uint32_t count = std::min(pData->options.maxParameters, plugin->getParameterCount()))
                 {
@@ -745,7 +748,7 @@ public:
 
     void handleNonRtData()
     {
-        CarlaPlugin* const plugin(pData->plugins[0].plugin);
+        const CarlaPluginPtr plugin = pData->plugins[0].plugin;
         CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
 
         for (; fShmNonRtClientControl.isDataAvailableForReading();)
@@ -1135,7 +1138,7 @@ protected:
             for (; fShmRtClientControl.isDataAvailableForReading();)
             {
                 const PluginBridgeRtClientOpcode opcode(fShmRtClientControl.readOpcode());
-                CarlaPlugin* const plugin(pData->plugins[0].plugin);
+                const CarlaPluginPtr plugin = pData->plugins[0].plugin;
 
 #ifdef DEBUG
                 if (opcode != kPluginBridgeRtClientProcess && opcode != kPluginBridgeRtClientMidiEvent) {

source/backend/engine/CarlaEngineClient.cpp

@@ -87,7 +87,9 @@ static void _getUniquePortName(CarlaString& sname, const CarlaStringList& list)
 // Carla Engine Client
 
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
-CarlaEngineClient::ProtectedData::ProtectedData(const CarlaEngine& eng, EngineInternalGraph& eg, CarlaPlugin* const p) noexcept
+CarlaEngineClient::ProtectedData::ProtectedData(const CarlaEngine& eng,
+                                                EngineInternalGraph& eg,
+                                                const CarlaPluginPtr p) noexcept
 #else
 CarlaEngineClient::ProtectedData::ProtectedData(const CarlaEngine& eng) noexcept
 #endif
@@ -106,6 +108,12 @@ CarlaEngineClient::ProtectedData::ProtectedData(const CarlaEngine& eng) noexcept
        eventInList(),
        eventOutList() {}
 
+CarlaEngineClient::ProtectedData::~ProtectedData()
+{
+    carla_debug("CarlaEngineClient::ProtectedData::~ProtectedData()");
+    CARLA_SAFE_ASSERT(plugin == nullptr);
+}
+
 void CarlaEngineClient::ProtectedData::addAudioPortName(const bool isInput, const char* const name)
 {
     CARLA_SAFE_ASSERT_RETURN(name != nullptr && name[0] != '\0',);
@@ -178,12 +186,20 @@ void CarlaEngineClient::activate() noexcept
     pData->active = true;
 }
 
-void CarlaEngineClient::deactivate() noexcept
+void CarlaEngineClient::deactivate(const bool willClose) noexcept
 {
     CARLA_SAFE_ASSERT(pData->active);
-    carla_debug("CarlaEngineClient::deactivate()");
+    carla_debug("CarlaEngineClient::deactivate(%s)", bool2str(willClose));
 
     pData->active = false;
+
+    if (willClose)
+    {
+#ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
+        pData->cvSourcePorts.setGraphAndPlugin(nullptr, nullptr);
+#endif
+        pData->plugin = nullptr;
+    }
 }
 
 bool CarlaEngineClient::isActive() const noexcept

source/backend/engine/CarlaEngineClient.hpp

@@ -20,6 +20,7 @@
 
 #include "CarlaEngine.hpp"
 #include "CarlaEnginePorts.hpp"
+#include "CarlaPlugin.hpp"
 
 #include "CarlaStringList.hpp"
 
@@ -37,7 +38,7 @@ struct CarlaEngineClient::ProtectedData {
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
     CarlaEngineCVSourcePortsForStandalone cvSourcePorts;
     EngineInternalGraph& egraph;
-    CarlaPlugin* const plugin;
+    CarlaPluginPtr plugin;
 #endif
 
     CarlaStringList audioInList;
@@ -48,10 +49,11 @@ struct CarlaEngineClient::ProtectedData {
     CarlaStringList eventOutList;
 
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
-    ProtectedData(const CarlaEngine& eng, EngineInternalGraph& eg, CarlaPlugin* p) noexcept;
+    ProtectedData(const CarlaEngine& eng, EngineInternalGraph& eg, CarlaPluginPtr p) noexcept;
 #else
     ProtectedData(const CarlaEngine& eng) noexcept;
 #endif
+    ~ProtectedData();
 
     void addAudioPortName(bool isInput, const char* name);
     void addCVPortName(bool isInput, const char* name);
@@ -72,11 +74,14 @@ struct CarlaEngineClient::ProtectedData {
 class CarlaEngineClientForStandalone : public CarlaEngineClient
 {
 public:
-    CarlaEngineClientForStandalone(const CarlaEngine& engine, EngineInternalGraph& egraph, CarlaPlugin* const plugin)
+    CarlaEngineClientForStandalone(const CarlaEngine& engine,
+                                   EngineInternalGraph& egraph,
+                                   const CarlaPluginPtr plugin)
         : CarlaEngineClient(new ProtectedData(engine, egraph, plugin)) {}
 
     ~CarlaEngineClientForStandalone() noexcept override
     {
+        carla_debug("CarlaEngineClientForStandalone::~CarlaEngineClientForStandalone()");
         delete pData;
     }
 
@@ -86,7 +91,7 @@ protected:
         return pData->egraph.getPatchbayGraphOrNull();
     }
 
-    inline CarlaPlugin* getPlugin() const noexcept
+    inline CarlaPluginPtr getPlugin() const noexcept
     {
         return pData->plugin;
     }
@@ -103,6 +108,7 @@ public:
 
     ~CarlaEngineClientForBridge() override
     {
+        carla_debug("CarlaEngineClientForBridge::~CarlaEngineClientForBridge()");
         delete pData;
     }
 

source/backend/engine/CarlaEngineGraph.cpp

@@ -967,7 +967,7 @@ void RackGraph::process(CarlaEngine::ProtectedData* const data, const float* inB
     // process plugins
     for (uint i=0; i < data->curPluginCount; ++i)
     {
-        CarlaPlugin* const plugin = data->plugins[i].plugin;
+        const CarlaPluginPtr plugin = data->plugins[i].plugin;
 
         if (plugin == nullptr || ! plugin->isEnabled() || ! plugin->tryLock(isOffline))
             continue;
@@ -1450,7 +1450,7 @@ void removeNodeFromPatchbay(const bool sendHost, const bool sendOSC, CarlaEngine
 class CarlaPluginInstance : public AudioProcessor
 {
 public:
-    CarlaPluginInstance(CarlaEngine* const engine, CarlaPlugin* const plugin)
+    CarlaPluginInstance(CarlaEngine* const engine, const CarlaPluginPtr plugin)
         : kEngine(engine),
           fPlugin(plugin)
     {
@@ -1641,7 +1641,7 @@ public:
 
 private:
     CarlaEngine* const kEngine;
-    CarlaPlugin* fPlugin;
+    CarlaPluginPtr fPlugin;
 
     CARLA_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(CarlaPluginInstance)
 };
@@ -1862,10 +1862,10 @@ void PatchbayGraph::setOffline(const bool offline)
     graph.setNonRealtime(offline);
 }
 
-void PatchbayGraph::addPlugin(CarlaPlugin* const plugin)
+void PatchbayGraph::addPlugin(const CarlaPluginPtr plugin)
 {
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
-    carla_debug("PatchbayGraph::addPlugin(%p)", plugin);
+    carla_debug("PatchbayGraph::addPlugin(%p)", plugin.get());
 
     CarlaPluginInstance* const instance(new CarlaPluginInstance(kEngine, plugin));
     AudioProcessorGraph::Node* const node(graph.addNode(instance));
@@ -1882,7 +1882,7 @@ void PatchbayGraph::addPlugin(CarlaPlugin* const plugin)
     addNodeToPatchbay(sendHost, sendOSC, kEngine, node, static_cast<int>(plugin->getId()), instance);
 }
 
-void PatchbayGraph::replacePlugin(CarlaPlugin* const oldPlugin, CarlaPlugin* const newPlugin)
+void PatchbayGraph::replacePlugin(const CarlaPluginPtr oldPlugin, const CarlaPluginPtr newPlugin)
 {
     CARLA_SAFE_ASSERT_RETURN(oldPlugin != nullptr,);
     CARLA_SAFE_ASSERT_RETURN(newPlugin != nullptr,);
@@ -1914,10 +1914,10 @@ void PatchbayGraph::replacePlugin(CarlaPlugin* const oldPlugin, CarlaPlugin* con
     addNodeToPatchbay(sendHost, sendOSC, kEngine, node, static_cast<int>(newPlugin->getId()), instance);
 }
 
-void PatchbayGraph::renamePlugin(CarlaPlugin* const plugin, const char* const newName)
+void PatchbayGraph::renamePlugin(const CarlaPluginPtr plugin, const char* const newName)
 {
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
-    carla_debug("PatchbayGraph::renamePlugin(%p)", plugin, newName);
+    carla_debug("PatchbayGraph::renamePlugin(%p)", plugin.get(), newName);
 
     AudioProcessorGraph::Node* const node(graph.getNodeForId(plugin->getPatchbayNodeId()));
     CARLA_SAFE_ASSERT_RETURN(node != nullptr,);
@@ -1932,10 +1932,10 @@ void PatchbayGraph::renamePlugin(CarlaPlugin* const plugin, const char* const ne
                       newName);
 }
 
-void PatchbayGraph::reconfigureForCV(CarlaPlugin* const plugin, const uint portIndex, bool added)
+void PatchbayGraph::reconfigureForCV(const CarlaPluginPtr plugin, const uint portIndex, bool added)
 {
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
-    carla_debug("PatchbayGraph::reconfigureForCV(%p, %u, %s)", plugin, portIndex, bool2str(added));
+    carla_debug("PatchbayGraph::reconfigureForCV(%p, %u, %s)", plugin.get(), portIndex, bool2str(added));
 
     AudioProcessorGraph::Node* const node = graph.getNodeForId(plugin->getPatchbayNodeId());
     CARLA_SAFE_ASSERT_RETURN(node != nullptr,);
@@ -1986,10 +1986,10 @@ void PatchbayGraph::reconfigureForCV(CarlaPlugin* const plugin, const uint portI
     }
 }
 
-void PatchbayGraph::removePlugin(CarlaPlugin* const plugin)
+void PatchbayGraph::removePlugin(const CarlaPluginPtr plugin)
 {
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
-    carla_debug("PatchbayGraph::removePlugin(%p)", plugin);
+    carla_debug("PatchbayGraph::removePlugin(%p)", plugin.get());
 
     AudioProcessorGraph::Node* const node(graph.getNodeForId(plugin->getPatchbayNodeId()));
     CARLA_SAFE_ASSERT_RETURN(node != nullptr,);
@@ -2005,7 +2005,7 @@ void PatchbayGraph::removePlugin(CarlaPlugin* const plugin)
     // Fix plugin Ids properties
     for (uint i=plugin->getId()+1, count=kEngine->getCurrentPluginCount(); i<count; ++i)
     {
-        CarlaPlugin* const plugin2(kEngine->getPlugin(i));
+        const CarlaPluginPtr plugin2 = kEngine->getPlugin(i);
         CARLA_SAFE_ASSERT_BREAK(plugin2 != nullptr);
 
         if (AudioProcessorGraph::Node* const node2 = graph.getNodeForId(plugin2->getPatchbayNodeId()))
@@ -2027,7 +2027,7 @@ void PatchbayGraph::removeAllPlugins()
 
     for (uint i=0, count=kEngine->getCurrentPluginCount(); i<count; ++i)
     {
-        CarlaPlugin* const plugin(kEngine->getPlugin(i));
+        const CarlaPluginPtr plugin = kEngine->getPlugin(i);
         CARLA_SAFE_ASSERT_CONTINUE(plugin != nullptr);
 
         AudioProcessorGraph::Node* const node(graph.getNodeForId(plugin->getPatchbayNodeId()));
@@ -2717,25 +2717,25 @@ void EngineInternalGraph::processRack(CarlaEngine::ProtectedData* const data, co
 // -----------------------------------------------------------------------
 // used for internal patchbay mode
 
-void EngineInternalGraph::addPlugin(CarlaPlugin* const plugin)
+void EngineInternalGraph::addPlugin(const CarlaPluginPtr plugin)
 {
     CARLA_SAFE_ASSERT_RETURN(fPatchbay != nullptr,);
     fPatchbay->addPlugin(plugin);
 }
 
-void EngineInternalGraph::replacePlugin(CarlaPlugin* const oldPlugin, CarlaPlugin* const newPlugin)
+void EngineInternalGraph::replacePlugin(const CarlaPluginPtr oldPlugin, const CarlaPluginPtr newPlugin)
 {
     CARLA_SAFE_ASSERT_RETURN(fPatchbay != nullptr,);
     fPatchbay->replacePlugin(oldPlugin, newPlugin);
 }
 
-void EngineInternalGraph::renamePlugin(CarlaPlugin* const plugin, const char* const newName)
+void EngineInternalGraph::renamePlugin(const CarlaPluginPtr plugin, const char* const newName)
 {
     CARLA_SAFE_ASSERT_RETURN(fPatchbay != nullptr,);
     fPatchbay->renamePlugin(plugin, newName);
 }
 
-void EngineInternalGraph::removePlugin(CarlaPlugin* const plugin)
+void EngineInternalGraph::removePlugin(const CarlaPluginPtr plugin)
 {
     CARLA_SAFE_ASSERT_RETURN(fPatchbay != nullptr,);
     fPatchbay->removePlugin(plugin);

source/backend/engine/CarlaEngineGraph.hpp

@@ -190,12 +190,12 @@ public:
     void setSampleRate(double sampleRate);
     void setOffline(bool offline);
 
-    void addPlugin(CarlaPlugin* plugin);
-    void replacePlugin(CarlaPlugin* oldPlugin, CarlaPlugin* newPlugin);
-    void renamePlugin(CarlaPlugin* plugin, const char* newName);
-    void reconfigureForCV(CarlaPlugin* const plugin, const uint portIndex, bool added);
-    void reconfigurePlugin(CarlaPlugin* plugin, bool portsAdded);
-    void removePlugin(CarlaPlugin* plugin);
+    void addPlugin(CarlaPluginPtr plugin);
+    void replacePlugin(CarlaPluginPtr oldPlugin, CarlaPluginPtr newPlugin);
+    void renamePlugin(CarlaPluginPtr plugin, const char* newName);
+    void reconfigureForCV(CarlaPluginPtr plugin, const uint portIndex, bool added);
+    void reconfigurePlugin(CarlaPluginPtr plugin, bool portsAdded);
+    void removePlugin(CarlaPluginPtr plugin);
     void removeAllPlugins();
 
     bool connect(bool external, uint groupA, uint portA, uint groupB, uint portB);

source/backend/engine/CarlaEngineInternal.cpp

@@ -404,6 +404,7 @@ CarlaEngine::ProtectedData::ProtectedData(CarlaEngine* const engine) noexcept
       xruns(0),
       dspLoad(0.0f),
 #endif
+      pluginsToDelete(),
       events(),
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
       graph(engine),
@@ -416,7 +417,7 @@ CarlaEngine::ProtectedData::ProtectedData(CarlaEngine* const engine) noexcept
 #endif
 }
 
-CarlaEngine::ProtectedData::~ProtectedData() noexcept
+CarlaEngine::ProtectedData::~ProtectedData()
 {
     CARLA_SAFE_ASSERT(curPluginCount == 0);
     CARLA_SAFE_ASSERT(maxPluginNumber == 0);
@@ -425,6 +426,17 @@ CarlaEngine::ProtectedData::~ProtectedData() noexcept
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
     CARLA_SAFE_ASSERT(plugins == nullptr);
 #endif
+
+    if (pluginsToDelete.size() != 0)
+    {
+        for (std::vector<CarlaPluginPtr>::iterator it = pluginsToDelete.begin(); it != pluginsToDelete.end(); ++it)
+        {
+            carla_stderr2("Plugin not yet deleted, name: '%s', usage count: '%u'",
+                          (*it)->getName(), it->use_count());
+        }
+    }
+
+    pluginsToDelete.clear();
 }
 
 // -----------------------------------------------------------------------
@@ -488,7 +500,6 @@ bool CarlaEngine::ProtectedData::init(const char* const clientName)
 
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
     plugins = new EnginePluginData[maxPluginNumber];
-    carla_zeroStructs(plugins, maxPluginNumber);
     xruns = 0;
     dspLoad = 0.0f;
 #endif
@@ -521,6 +532,8 @@ void CarlaEngine::ProtectedData::close()
     maxPluginNumber = 0;
     nextPluginId    = 0;
 
+    deletePluginsAsNeeded();
+
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
     if (plugins != nullptr)
     {
@@ -550,6 +563,29 @@ void CarlaEngine::ProtectedData::initTime(const char* const features)
 
 // -----------------------------------------------------------------------
 
+void CarlaEngine::ProtectedData::deletePluginsAsNeeded()
+{
+    for (bool stop;;)
+    {
+        stop = true;
+
+        for (std::vector<CarlaPluginPtr>::iterator it = pluginsToDelete.begin(); it != pluginsToDelete.end(); ++it)
+        {
+            if (it->use_count() == 1)
+            {
+                stop = false;
+                pluginsToDelete.erase(it);
+                break;
+            }
+        }
+
+        if (stop)
+            break;
+    }
+}
+
+// -----------------------------------------------------------------------
+
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
 void CarlaEngine::ProtectedData::doPluginRemove(const uint pluginId) noexcept
 {
@@ -560,17 +596,16 @@ void CarlaEngine::ProtectedData::doPluginRemove(const uint pluginId) noexcept
     // move all plugins 1 spot backwards
     for (uint i=pluginId; i < curPluginCount; ++i)
     {
-        CarlaPlugin* const plugin(plugins[i+1].plugin);
-
+        const CarlaPluginPtr plugin = plugins[i+1].plugin;
         CARLA_SAFE_ASSERT_BREAK(plugin != nullptr);
 
         plugin->setId(i);
 
         plugins[i].plugin = plugin;
-        carla_zeroFloats(plugins[i].peaks, 4);
+        carla_zeroStruct(plugins[i].peaks);
     }
 
-    const uint id(curPluginCount);
+    const uint id = curPluginCount;
 
     // reset last plugin (now removed)
     plugins[id].plugin = nullptr;
@@ -584,10 +619,10 @@ void CarlaEngine::ProtectedData::doPluginsSwitch(const uint idA, const uint idB)
     CARLA_SAFE_ASSERT_RETURN(idA < curPluginCount,);
     CARLA_SAFE_ASSERT_RETURN(idB < curPluginCount,);
 
-    CarlaPlugin* const pluginA(plugins[idA].plugin);
+    const CarlaPluginPtr pluginA = plugins[idA].plugin;
     CARLA_SAFE_ASSERT_RETURN(pluginA != nullptr,);
 
-    CarlaPlugin* const pluginB(plugins[idB].plugin);
+    const CarlaPluginPtr pluginB = plugins[idB].plugin;
     CARLA_SAFE_ASSERT_RETURN(pluginB != nullptr,);
 
     pluginA->setId(idB);

source/backend/engine/CarlaEngineInternal.hpp

@@ -33,6 +33,8 @@
 # include "water/memory/Atomic.h"
 #endif
 
+#include <vector>
+
 // FIXME only use CARLA_PREVENT_HEAP_ALLOCATION for structs
 // maybe separate macro
 
@@ -96,10 +98,10 @@ public:
     void processRack(CarlaEngine::ProtectedData* data, const float* inBuf[2], float* outBuf[2], uint32_t frames);
 
     // used for internal patchbay mode
-    void addPlugin(CarlaPlugin* plugin);
-    void replacePlugin(CarlaPlugin* oldPlugin, CarlaPlugin* newPlugin);
-    void renamePlugin(CarlaPlugin* plugin, const char* newName);
-    void removePlugin(CarlaPlugin* plugin);
+    void addPlugin(CarlaPluginPtr plugin);
+    void replacePlugin(CarlaPluginPtr oldPlugin, CarlaPluginPtr newPlugin);
+    void renamePlugin(CarlaPluginPtr plugin, const char* newName);
+    void removePlugin(CarlaPluginPtr plugin);
     void removeAllPlugins();
 
     bool isUsingExternalHost() const noexcept;
@@ -208,8 +210,12 @@ struct EngineNextAction {
 // EnginePluginData
 
 struct EnginePluginData {
-    CarlaPlugin* plugin;
+    CarlaPluginPtr plugin;
     float peaks[4];
+
+    EnginePluginData()
+        : plugin(nullptr),
+          peaks{0.0f, 0.0f, 0.0f, 0.0f} {}
 };
 
 // -----------------------------------------------------------------------
@@ -258,6 +264,7 @@ struct CarlaEngine::ProtectedData {
     float dspLoad;
 #endif
     float peaks[4];
+    std::vector<CarlaPluginPtr> pluginsToDelete;
 
     EngineInternalEvents events;
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
@@ -280,6 +287,10 @@ struct CarlaEngine::ProtectedData {
 
     // -------------------------------------------------------------------
 
+    void deletePluginsAsNeeded();
+
+    // -------------------------------------------------------------------
+
     void doPluginRemove(uint pluginId) noexcept;
     void doPluginsSwitch(uint idA, uint idB) noexcept;
     void doNextPluginAction() noexcept;

source/backend/engine/CarlaEngineJack.cpp

@@ -745,7 +745,7 @@ public:
         return pData->cvs[ioffset].cvPort;
     }
 
-    void setGraphAndPlugin(PatchbayGraph* const graph, CarlaPlugin* const plugin) noexcept
+    void setGraphAndPlugin(PatchbayGraph* const graph, CarlaPluginPtr plugin) noexcept
     {
         pData->graph = graph;
         pData->plugin = plugin;
@@ -771,7 +771,7 @@ public:
     CarlaEngineJackClient(const CarlaEngine& engine,
                           EngineInternalGraph& egraph,
                           CarlaRecursiveMutex& rmutex,
-                          CarlaPlugin* const plugin,
+                          const CarlaPluginPtr plugin,
                           const CarlaString& mainClientName,
                           jack_client_t* const jackClient)
         : CarlaEngineClientForSubclassing(engine, egraph, plugin),
@@ -794,6 +794,7 @@ public:
           fPreRenameConnections(),
           fPreRenamePluginId(),
           fPreRenamePluginIcon(),
+          fReservedPluginPtr(),
 #endif
           fThreadSafeMetadataMutex(rmutex),
           fMainClientName(mainClientName)
@@ -913,9 +914,9 @@ public:
 #endif
     }
 
-    void deactivate() noexcept override
+    void deactivate(const bool willClose) noexcept override
     {
-        carla_debug("CarlaEngineJackClient::deactivate()");
+        carla_debug("CarlaEngineJackClient::deactivate(%s)", bool2str(willClose));
 
         if (getProcessMode() == ENGINE_PROCESS_MODE_MULTIPLE_CLIENTS)
         {
@@ -926,7 +927,15 @@ public:
             } catch(...) {}
         }
 
-        CarlaEngineClient::deactivate();
+        if (willClose)
+        {
+            fCVSourcePorts.setGraphAndPlugin(nullptr, nullptr);
+#ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
+            fReservedPluginPtr = nullptr;
+#endif
+        }
+
+        CarlaEngineClient::deactivate(willClose);
     }
 
     bool isOk() const noexcept override
@@ -1071,7 +1080,7 @@ public:
         }
 
         fJackClient = nullptr;
-        CarlaEngineClient::deactivate();
+        CarlaEngineClient::deactivate(true);
     }
 
     const char* getJackClientName() const noexcept
@@ -1150,6 +1159,11 @@ public:
         fJackClient = newClient;
     }
 
+    void reservePluginPtr(CarlaPluginPtr* const pluginPtr)
+    {
+        fReservedPluginPtr = pluginPtr;
+    }
+
     void setNewPluginId(const uint id) const
     {
         // NOTE: no fThreadSafeMetadataMutex lock here, assumed done from caller
@@ -1190,6 +1204,8 @@ private:
     CarlaString     fPreRenamePluginId;
     CarlaString     fPreRenamePluginIcon;
 
+    CarlaScopedPointer<CarlaPluginPtr> fReservedPluginPtr;
+
     template<typename T>
     bool _renamePorts(const LinkedList<T*>& t, const CarlaString& clientNamePrefix)
     {
@@ -1885,11 +1901,13 @@ public:
     }
 #endif
 
-    CarlaEngineClient* addClient(CarlaPlugin* const plugin) override
+    CarlaEngineClient* addClient(CarlaPluginPtr plugin) override
     {
         jack_client_t* client = nullptr;
 
 #ifndef BUILD_BRIDGE
+        CarlaPluginPtr* pluginReserve = nullptr;
+
         if (pData->options.processMode == ENGINE_PROCESS_MODE_SINGLE_CLIENT)
         {
             client = fClient;
@@ -1937,13 +1955,14 @@ public:
             }
 
 #ifndef BUILD_BRIDGE
+            pluginReserve = new CarlaPluginPtr(plugin);
             /*
-            jackbridge_set_buffer_size_callback(fClient, carla_jack_bufsize_callback_plugin, plugin);
-            jackbridge_set_sample_rate_callback(fClient, carla_jack_srate_callback_plugin, plugin);
+            jackbridge_set_buffer_size_callback(fClient, carla_jack_bufsize_callback_plugin, pluginReserve);
+            jackbridge_set_sample_rate_callback(fClient, carla_jack_srate_callback_plugin, pluginReserve);
             */
-            jackbridge_set_latency_callback(client, carla_jack_latency_callback_plugin, plugin);
-            jackbridge_set_process_callback(client, carla_jack_process_callback_plugin, plugin);
-            jackbridge_on_shutdown(client, carla_jack_shutdown_callback_plugin, plugin);
+            jackbridge_set_latency_callback(client, carla_jack_latency_callback_plugin, pluginReserve);
+            jackbridge_set_process_callback(client, carla_jack_process_callback_plugin, pluginReserve);
+            jackbridge_on_shutdown(client, carla_jack_shutdown_callback_plugin, pluginReserve);
 #else
             fClient = client;
             pData->bufferSize = jackbridge_get_buffer_size(client);
@@ -1962,7 +1981,16 @@ public:
         }
 
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
-        return new CarlaEngineJackClient(*this, pData->graph, fThreadSafeMetadataMutex, plugin, fClientName, client);
+        CarlaEngineJackClient* const jclient = new CarlaEngineJackClient(*this,
+                                                                         pData->graph,
+                                                                         fThreadSafeMetadataMutex,
+                                                                         plugin, fClientName, client);
+# ifndef BUILD_BRIDGE
+        if (pluginReserve != nullptr)
+            jclient->reservePluginPtr(pluginReserve);
+# endif
+        return jclient;
+
 #else
         return new CarlaEngineJackClient(*this, fThreadSafeMetadataMutex, fClientName, client);
 #endif
@@ -1978,7 +2006,7 @@ public:
 
         for (uint i=id; i < pData->curPluginCount; ++i)
         {
-            CarlaPlugin* const plugin = pData->plugins[i].plugin;
+            const CarlaPluginPtr plugin = pData->plugins[i].plugin;
             CARLA_SAFE_ASSERT_BREAK(plugin != nullptr);
 
             CarlaEngineJackClient* const client = dynamic_cast<CarlaEngineJackClient*>(plugin->getEngineClient());
@@ -1995,10 +2023,10 @@ public:
         if (! CarlaEngine::switchPlugins(idA, idB))
             return false;
 
-        CarlaPlugin* const newPluginA(pData->plugins[idA].plugin);
+        CarlaPluginPtr newPluginA = pData->plugins[idA].plugin;
         CARLA_SAFE_ASSERT_RETURN(newPluginA != nullptr, true);
 
-        CarlaPlugin* const newPluginB(pData->plugins[idB].plugin);
+        CarlaPluginPtr newPluginB = pData->plugins[idB].plugin;
         CARLA_SAFE_ASSERT_RETURN(newPluginB != nullptr, true);
 
         CarlaEngineJackClient* const clientA = dynamic_cast<CarlaEngineJackClient*>(newPluginA->getEngineClient());
@@ -2029,7 +2057,7 @@ public:
         CARLA_SAFE_ASSERT_RETURN(id < pData->curPluginCount, false);
         CARLA_SAFE_ASSERT_RETURN(newName != nullptr && newName[0] != '\0', false);
 
-        CarlaPlugin* const plugin(pData->plugins[id].plugin);
+        CarlaPluginPtr plugin = pData->plugins[id].plugin;
         CARLA_SAFE_ASSERT_RETURN_ERR(plugin != nullptr, "Could not find plugin to rename");
         CARLA_SAFE_ASSERT_RETURN_ERR(plugin->getId() == id, "Invalid engine internal data");
 
@@ -2089,9 +2117,11 @@ public:
                 plugin->setEnabled(false);
 
                 // set new client data
-                jackbridge_set_latency_callback(jackClient, carla_jack_latency_callback_plugin, plugin);
-                jackbridge_set_process_callback(jackClient, carla_jack_process_callback_plugin, plugin);
-                jackbridge_on_shutdown(jackClient, carla_jack_shutdown_callback_plugin, plugin);
+                CarlaPluginPtr* const pluginReserve = new CarlaPluginPtr(plugin);
+                client->reservePluginPtr(pluginReserve);
+                jackbridge_set_latency_callback(jackClient, carla_jack_latency_callback_plugin, pluginReserve);
+                jackbridge_set_process_callback(jackClient, carla_jack_process_callback_plugin, pluginReserve);
+                jackbridge_on_shutdown(jackClient, carla_jack_shutdown_callback_plugin, pluginReserve);
 
                 // NOTE: jack1 locks up here
                 if (jackbridge_get_version_string() != nullptr)
@@ -2736,7 +2766,7 @@ protected:
         CARLA_SAFE_ASSERT_INT2_RETURN(nframes == pData->bufferSize, nframes, pData->bufferSize,);
 
 #ifdef BUILD_BRIDGE
-        CarlaPlugin* const plugin(pData->plugins[0].plugin);
+        CarlaPluginPtr plugin = pData->plugins[0].plugin;
 
         if (plugin != nullptr && plugin->isEnabled() && plugin->tryLock(fFreewheel))
         {
@@ -2829,7 +2859,7 @@ protected:
         {
             for (uint i=0; i < pData->curPluginCount; ++i)
             {
-                CarlaPlugin* const plugin(pData->plugins[i].plugin);
+                CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
                 if (plugin != nullptr && plugin->isEnabled() && plugin->tryLock(fFreewheel))
                 {
@@ -2943,8 +2973,11 @@ protected:
                             // set first byte
                             mdataTmp[0] = static_cast<uint8_t>(midiEvent.data[0] | (engineEvent.channel & MIDI_CHANNEL_BIT));
 
-                            // copy rest
-                            carla_copy<uint8_t>(mdataTmp+1, midiEvent.data+1, size-1U);
+                            if (size > 1)
+                            {
+                                // copy rest
+                                carla_copy<uint8_t>(mdataTmp+1, midiEvent.data+1, size-1U);
+                            }
 
                             // done
                             mdataPtr = mdataTmp;
@@ -3339,7 +3372,7 @@ protected:
 
         for (uint i=0; i < pData->curPluginCount; ++i)
         {
-            if (CarlaPlugin* const plugin = pData->plugins[i].plugin)
+            if (CarlaPluginPtr plugin = pData->plugins[i].plugin)
             {
                 plugin->tryLock(true);
 
@@ -3794,7 +3827,7 @@ private:
 
     // -------------------------------------------------------------------
 
-    void processPlugin(CarlaPlugin* const plugin, const uint32_t nframes)
+    void processPlugin(CarlaPluginPtr& plugin, const uint32_t nframes)
     {
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
         CarlaEngineJackClient* const client = (CarlaEngineJackClient*)plugin->getEngineClient();
@@ -4230,7 +4263,10 @@ private:
 #ifndef BUILD_BRIDGE
     static int JACKBRIDGE_API carla_jack_process_callback_plugin(jack_nframes_t nframes, void* arg) __attribute__((annotate("realtime")))
     {
-        CarlaPlugin* const plugin((CarlaPlugin*)arg);
+        CarlaPluginPtr* const pluginPtr = static_cast<CarlaPluginPtr*>(arg);
+        CARLA_SAFE_ASSERT_RETURN(pluginPtr != nullptr, 0);
+
+        CarlaPluginPtr plugin = *pluginPtr;
         CARLA_SAFE_ASSERT_RETURN(plugin != nullptr && plugin->isEnabled(), 0);
 
         CarlaEngineJack* const engine((CarlaEngineJack*)plugin->getEngine());

source/backend/engine/CarlaEngineNative.cpp

@@ -155,8 +155,9 @@ protected:
 private:
     CarlaEngineNative* const fEngine;
 
-    void _updateParamValues(CarlaPlugin* const plugin, const uint32_t pluginId,
-                            const bool sendCallback, const bool sendPluginHost) const noexcept;
+    void _updateParamValues(const CarlaPluginPtr& plugin,
+                            uint32_t pluginId,
+                            bool sendCallback, bool sendPluginHost) const noexcept;
 
     CARLA_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(CarlaEngineNativeUI)
 };
@@ -446,7 +447,7 @@ protected:
 
     // -------------------------------------------------------------------
 
-    void uiServerSendPluginInfo(CarlaPlugin* const plugin)
+    void uiServerSendPluginInfo(const CarlaPluginPtr& plugin)
     {
         char tmpBuf[STR_MAX+1];
         carla_zeroChars(tmpBuf, STR_MAX+1);
@@ -518,16 +519,18 @@ protected:
             CARLA_SAFE_ASSERT_RETURN(fUiServer.writeEmptyMessage(),);
         }
 
-        std::snprintf(tmpBuf, STR_MAX, "AUDIO_COUNT_%i:%i:%i\n", pluginId, plugin->getAudioInCount(), plugin->getAudioOutCount());
+        std::snprintf(tmpBuf, STR_MAX, "AUDIO_COUNT_%i:%i:%i\n",
+                      pluginId, plugin->getAudioInCount(), plugin->getAudioOutCount());
         CARLA_SAFE_ASSERT_RETURN(fUiServer.writeMessage(tmpBuf),);
 
-        std::snprintf(tmpBuf, STR_MAX, "MIDI_COUNT_%i:%i:%i\n", pluginId, plugin->getMidiInCount(), plugin->getMidiOutCount());
+        std::snprintf(tmpBuf, STR_MAX, "MIDI_COUNT_%i:%i:%i\n",
+                      pluginId, plugin->getMidiInCount(), plugin->getMidiOutCount());
         CARLA_SAFE_ASSERT_RETURN(fUiServer.writeMessage(tmpBuf),);
 
         fUiServer.flushMessages();
     }
 
-    void uiServerSendPluginParameters(CarlaPlugin* const plugin)
+    void uiServerSendPluginParameters(const CarlaPluginPtr& plugin)
     {
         char tmpBuf[STR_MAX+1];
         carla_zeroChars(tmpBuf, STR_MAX+1);
@@ -617,7 +620,7 @@ protected:
         fUiServer.flushMessages();
     }
 
-    void uiServerSendPluginPrograms(CarlaPlugin* const plugin)
+    void uiServerSendPluginPrograms(const CarlaPluginPtr& plugin)
     {
         char tmpBuf[STR_MAX+1];
         carla_zeroChars(tmpBuf, STR_MAX+1);
@@ -645,7 +648,8 @@ protected:
         fUiServer.flushMessages();
 
         count = plugin->getMidiProgramCount();
-        std::snprintf(tmpBuf, STR_MAX, "MIDI_PROGRAM_COUNT_%i:%i:%i\n", pluginId, count, plugin->getCurrentMidiProgram());
+        std::snprintf(tmpBuf, STR_MAX, "MIDI_PROGRAM_COUNT_%i:%i:%i\n",
+                      pluginId, count, plugin->getCurrentMidiProgram());
         CARLA_SAFE_ASSERT_RETURN(fUiServer.writeMessage(tmpBuf),);
 
         for (uint32_t i=0; i<count; ++i)
@@ -665,7 +669,7 @@ protected:
         fUiServer.flushMessages();
     }
 
-    void uiServerSendPluginProperties(CarlaPlugin* const plugin)
+    void uiServerSendPluginProperties(const CarlaPluginPtr& plugin)
     {
         char tmpBuf[STR_MAX+1];
         carla_zeroChars(tmpBuf, STR_MAX+1);
@@ -705,7 +709,7 @@ protected:
         if (! fUiServer.isPipeRunning())
             return;
 
-        CarlaPlugin* plugin;
+        CarlaPluginPtr plugin;
 
         switch (action)
         {
@@ -957,7 +961,7 @@ protected:
         carla_zeroChars(strBufGroupName, STR_MAX+1);
 
         uint32_t rindex = index;
-        if (CarlaPlugin* const plugin = _getPluginForParameterIndex(rindex))
+        if (const CarlaPluginPtr plugin = _getPluginForParameterIndex(rindex))
         {
             const ParameterData& paramData(plugin->getParameterData(rindex));
             const ParameterRanges& paramRanges(plugin->getParameterRanges(rindex));
@@ -1029,7 +1033,7 @@ protected:
     float getParameterValue(const uint32_t index) const
     {
         uint32_t rindex = index;
-        if (CarlaPlugin* const plugin = _getPluginForParameterIndex(rindex))
+        if (const CarlaPluginPtr plugin = _getPluginForParameterIndex(rindex))
             return plugin->getParameterValue(rindex);
 
         return fParameters[index];
@@ -1041,7 +1045,7 @@ protected:
     void setParameterValue(const uint32_t index, const float value)
     {
         uint32_t rindex = index;
-        if (CarlaPlugin* const plugin = _getPluginForParameterIndex(rindex))
+        if (const CarlaPluginPtr plugin = _getPluginForParameterIndex(rindex))
             plugin->setParameterValueRT(rindex, value, false);
 
         fParameters[index] = value;
@@ -1055,7 +1059,7 @@ protected:
 #if 0
         for (uint i=0; i < pData->curPluginCount; ++i)
         {
-            CarlaPlugin* const plugin(pData->plugins[i].plugin);
+            CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
             if (plugin == nullptr || ! plugin->isEnabled())
                 continue;
@@ -1072,7 +1076,7 @@ protected:
 #if 0
         for (uint i=0; i < pData->curPluginCount; ++i)
         {
-            CarlaPlugin* const plugin(pData->plugins[i].plugin);
+            CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
             if (plugin == nullptr || ! plugin->isEnabled())
                 continue;
@@ -1283,7 +1287,7 @@ protected:
 
             for (uint i=0; i < pData->curPluginCount; ++i)
             {
-                CarlaPlugin* const plugin(pData->plugins[i].plugin);
+                CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
                 if (plugin != nullptr && plugin->isEnabled())
                 {
@@ -1301,7 +1305,7 @@ protected:
             // hide all custom uis
             for (uint i=0; i < pData->curPluginCount; ++i)
             {
-                CarlaPlugin* const plugin(pData->plugins[i].plugin);
+                CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
                 if (plugin != nullptr && plugin->isEnabled())
                 {
@@ -1320,7 +1324,7 @@ protected:
     {
         for (uint i=0; i < pData->curPluginCount; ++i)
         {
-            CarlaPlugin* const plugin(pData->plugins[i].plugin);
+            CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
             if (plugin != nullptr && plugin->isEnabled())
             {
@@ -1365,7 +1369,7 @@ protected:
     void uiSetParameterValue(const uint32_t index, const float value)
     {
         uint32_t rindex = index;
-        if (CarlaPlugin* const plugin = _getPluginForParameterIndex(rindex))
+        if (const CarlaPluginPtr plugin = _getPluginForParameterIndex(rindex))
         {
             if (plugin->getHints() & PLUGIN_HAS_CUSTOM_UI)
                 plugin->uiParameterChange(rindex, value);
@@ -1436,7 +1440,7 @@ protected:
         for (uint i=0; i < pData->curPluginCount; ++i)
         {
             const EnginePluginData& plugData(pData->plugins[i]);
-            const CarlaPlugin* const plugin(pData->plugins[i].plugin);
+            const CarlaPluginPtr plugin = pData->plugins[i].plugin;
 
             std::snprintf(tmpBuf, STR_MAX, "PEAKS_%i\n", i);
             CARLA_SAFE_ASSERT_RETURN(fUiServer.writeMessage(tmpBuf),);
@@ -1684,12 +1688,12 @@ private:
 
     bool fOptionsForced;
 
-    CarlaPlugin* _getPluginForParameterIndex(uint32_t& index) const noexcept
+    CarlaPluginPtr _getPluginForParameterIndex(uint32_t& index) const noexcept
     {
         if (pData->curPluginCount == 0 || pData->plugins == nullptr)
             return nullptr;
 
-        CarlaPlugin* plugin;
+        CarlaPluginPtr plugin;
 
         for (uint32_t i=0; i<pData->curPluginCount; ++i)
         {
@@ -1718,7 +1722,7 @@ private:
         if (pData->curPluginCount == 0 || pluginId >= pData->curPluginCount || pData->plugins == nullptr)
             return false;
 
-        CarlaPlugin* plugin;
+        CarlaPluginPtr plugin;
 
         for (uint32_t i=0; i<pluginId; ++i)
         {
@@ -1978,7 +1982,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsString(filename, false), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
         {
             plugin->loadStateFromFile(filename);
             _updateParamValues(plugin, pluginId, false, true);
@@ -1992,7 +1996,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsString(filename, false), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->saveStateToFile(filename);
     }
     else if (std::strcmp(msg, "set_option") == 0)
@@ -2004,7 +2008,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(option), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsBool(yesNo), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setOption(option, yesNo, false);
     }
     else if (std::strcmp(msg, "set_active") == 0)
@@ -2015,7 +2019,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsBool(onOff), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setActive(onOff, true, false);
     }
     else if (std::strcmp(msg, "set_drywet") == 0)
@@ -2026,7 +2030,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsFloat(value), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setDryWet(value, true, false);
     }
     else if (std::strcmp(msg, "set_volume") == 0)
@@ -2037,7 +2041,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsFloat(value), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setVolume(value, true, false);
     }
     else if (std::strcmp(msg, "set_balance_left") == 0)
@@ -2048,7 +2052,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsFloat(value), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setBalanceLeft(value, true, false);
     }
     else if (std::strcmp(msg, "set_balance_right") == 0)
@@ -2059,7 +2063,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsFloat(value), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setBalanceRight(value, true, false);
     }
     else if (std::strcmp(msg, "set_panning") == 0)
@@ -2070,7 +2074,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsFloat(value), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setPanning(value, true, false);
     }
     else if (std::strcmp(msg, "set_ctrl_channel") == 0)
@@ -2082,7 +2086,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsInt(channel), true);
         CARLA_SAFE_ASSERT_RETURN(channel >= -1 && channel < MAX_MIDI_CHANNELS, true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setCtrlChannel(int8_t(channel), true, false);
     }
     else if (std::strcmp(msg, "set_parameter_value") == 0)
@@ -2094,7 +2098,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(parameterId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsFloat(value), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
         {
             plugin->setParameterValue(parameterId, value, true, true, false);
             fEngine->setParameterValueFromUI(pluginId, parameterId, value);
@@ -2109,7 +2113,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(channel), true);
         CARLA_SAFE_ASSERT_RETURN(channel < MAX_MIDI_CHANNELS, true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setParameterMidiChannel(parameterId, static_cast<uint8_t>(channel), true, false);
     }
     else if (std::strcmp(msg, "set_parameter_mapped_control_index") == 0)
@@ -2122,7 +2126,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsInt(ctrl), true);
         CARLA_SAFE_ASSERT_RETURN(ctrl >= CONTROL_INDEX_NONE && ctrl <= CONTROL_INDEX_MAX_ALLOWED, true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setParameterMappedControlIndex(parameterId, static_cast<int16_t>(ctrl), true, false);
     }
     else if (std::strcmp(msg, "set_parameter_mapped_range") == 0)
@@ -2135,7 +2139,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsFloat(minimum), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsFloat(maximum), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setParameterMappedRange(parameterId, minimum, maximum, true, false);
     }
     else if (std::strcmp(msg, "set_parameter_touch") == 0)
@@ -2158,7 +2162,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsInt(index), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
         {
             plugin->setProgram(index, true, true, false);
             _updateParamValues(plugin, pluginId, true, true);
@@ -2172,7 +2176,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsInt(index), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
         {
             plugin->setMidiProgram(index, true, true, false);
             _updateParamValues(plugin, pluginId, true, true);
@@ -2190,7 +2194,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsString(key, true), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsString(value, false), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->setCustomData(type, key, value, true);
 
         delete[] type;
@@ -2204,7 +2208,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsString(cdata, false), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
         {
             std::vector<uint8_t> chunk(carla_getChunkFromBase64String(cdata));
 #ifdef CARLA_PROPER_CPP11_SUPPORT
@@ -2221,7 +2225,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
 
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->prepareForSave();
     }
     else if (std::strcmp(msg, "reset_parameters") == 0)
@@ -2230,7 +2234,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
 
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
         {
             plugin->resetParameters();
             _updateParamValues(plugin, pluginId, false, true);
@@ -2242,7 +2246,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
 
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
         {
             plugin->randomizeParameters();
             _updateParamValues(plugin, pluginId, false, true);
@@ -2260,7 +2264,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(note < MAX_MIDI_VALUE, true);
         CARLA_SAFE_ASSERT_RETURN(velocity < MAX_MIDI_VALUE, true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->sendMidiSingleNote(static_cast<uint8_t>(channel), static_cast<uint8_t>(note), static_cast<uint8_t>(velocity), true, true, false);
     }
     else if (std::strcmp(msg, "show_custom_ui") == 0)
@@ -2271,7 +2275,7 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsUInt(pluginId), true);
         CARLA_SAFE_ASSERT_RETURN(readNextLineAsBool(yesNo), true);
 
-        if (CarlaPlugin* const plugin = fEngine->getPlugin(pluginId))
+        if (const CarlaPluginPtr plugin = fEngine->getPlugin(pluginId))
             plugin->showCustomUI(yesNo);
     }
     else
@@ -2291,7 +2295,8 @@ bool CarlaEngineNativeUI::msgReceived(const char* const msg) noexcept
     return true;
 }
 
-void CarlaEngineNativeUI::_updateParamValues(CarlaPlugin* const plugin, const uint32_t pluginId,
+void CarlaEngineNativeUI::_updateParamValues(const CarlaPluginPtr& plugin,
+                                             const uint32_t pluginId,
                                              const bool sendCallback, const bool sendPluginHost) const noexcept
 {
     float value;

source/backend/engine/CarlaEngineOsc.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla Plugin Host
- * Copyright (C) 2011-2019 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2011-2020 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

source/backend/engine/CarlaEngineOsc.hpp

@@ -1,6 +1,6 @@
 /*
  * Carla Plugin Host
- * Copyright (C) 2011-2019 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2011-2020 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
@@ -27,7 +27,10 @@
 #include "CarlaOscUtils.hpp"
 #include "CarlaString.hpp"
 
-#define CARLA_ENGINE_OSC_HANDLE_ARGS CarlaPlugin* const plugin, const int argc, const lo_arg* const* const argv, const char* const types
+#include <memory>
+
+#define CARLA_ENGINE_OSC_HANDLE_ARGS const CarlaPluginPtr& plugin, \
+  const int argc, const lo_arg* const* const argv, const char* const types
 
 #define CARLA_ENGINE_OSC_CHECK_OSC_TYPES(/* argc, types, */ argcToCompare, typesToCompare)                                     \
     /* check argument count */                                                                                                 \
@@ -54,6 +57,8 @@
 
 CARLA_BACKEND_START_NAMESPACE
 
+typedef std::shared_ptr<CarlaPlugin> CarlaPluginPtr;
+
 // -----------------------------------------------------------------------
 
 class CarlaEngineOsc
@@ -96,15 +101,15 @@ public:
     void sendCallback(EngineCallbackOpcode action, uint pluginId,
                       int value1, int value2, int value3,
                       float valuef, const char* valueStr) const noexcept;
-    void sendPluginInfo(const CarlaPlugin* plugin) const noexcept;
-    void sendPluginPortCount(const CarlaPlugin* plugin) const noexcept;
-    void sendPluginParameterInfo(const CarlaPlugin* plugin, uint32_t index) const noexcept;
-    void sendPluginDataCount(const CarlaPlugin* plugin) const noexcept;
-    void sendPluginProgramCount(const CarlaPlugin* plugin) const noexcept;
-    void sendPluginProgram(const CarlaPlugin* plugin, uint32_t index) const noexcept;
-    void sendPluginMidiProgram(const CarlaPlugin* plugin, uint32_t index) const noexcept;
-    void sendPluginCustomData(const CarlaPlugin* plugin, uint32_t index) const noexcept;
-    void sendPluginInternalParameterValues(const CarlaPlugin* plugin) const noexcept;
+    void sendPluginInfo(const CarlaPluginPtr& plugin) const noexcept;
+    void sendPluginPortCount(const CarlaPluginPtr& plugin) const noexcept;
+    void sendPluginParameterInfo(const CarlaPluginPtr& plugin, uint32_t index) const noexcept;
+    void sendPluginDataCount(const CarlaPluginPtr& plugin) const noexcept;
+    void sendPluginProgramCount(const CarlaPluginPtr& plugin) const noexcept;
+    void sendPluginProgram(const CarlaPluginPtr& plugin, uint32_t index) const noexcept;
+    void sendPluginMidiProgram(const CarlaPluginPtr& plugin, uint32_t index) const noexcept;
+    void sendPluginCustomData(const CarlaPluginPtr& plugin, uint32_t index) const noexcept;
+    void sendPluginInternalParameterValues(const CarlaPluginPtr& plugin) const noexcept;
     void sendPing() const noexcept;
     void sendResponse(int messageId, const char* error) const noexcept;
     void sendExit() const noexcept;

source/backend/engine/CarlaEngineOscHandlers.cpp

@@ -122,7 +122,7 @@ int CarlaEngineOsc::handleMessage(const bool isTCP, const char* const path, cons
     }
 
     // Get plugin
-    CarlaPlugin* const plugin(fEngine->getPluginUnchecked(pluginId));
+    const CarlaPluginPtr plugin = fEngine->getPluginUnchecked(pluginId);
 
     if (plugin == nullptr || plugin->getId() != pluginId)
     {
@@ -239,7 +239,7 @@ int CarlaEngineOsc::handleMsgRegister(const bool isTCP,
 
             for (uint i=0, count=fEngine->getCurrentPluginCount(); i < count; ++i)
             {
-                CarlaPlugin* const plugin(fEngine->getPluginUnchecked(i));
+                const CarlaPluginPtr plugin = fEngine->getPluginUnchecked(i);
                 CARLA_SAFE_ASSERT_CONTINUE(plugin != nullptr);
 
                 fEngine->callback(false, true, ENGINE_CALLBACK_PLUGIN_ADDED, i, 0, 0, 0, 0.0f, plugin->getName());

source/backend/engine/CarlaEngineOscSend.cpp

@@ -47,7 +47,7 @@ void CarlaEngineOsc::sendCallback(const EngineCallbackOpcode action, const uint
                 valueStr != nullptr ? valueStr : kNullString);
 }
 
-void CarlaEngineOsc::sendPluginInfo(const CarlaPlugin* const plugin) const noexcept
+void CarlaEngineOsc::sendPluginInfo(const CarlaPluginPtr& plugin) const noexcept
 {
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.path != nullptr && fControlDataTCP.path[0] != '\0',);
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.target != nullptr,);
@@ -95,7 +95,7 @@ void CarlaEngineOsc::sendPluginInfo(const CarlaPlugin* const plugin) const noexc
                 bufRealName, bufLabel, bufMaker, bufCopyright);
 }
 
-void CarlaEngineOsc::sendPluginPortCount(const CarlaPlugin* const plugin) const noexcept
+void CarlaEngineOsc::sendPluginPortCount(const CarlaPluginPtr& plugin) const noexcept
 {
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.path != nullptr && fControlDataTCP.path[0] != '\0',);
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.target != nullptr,);
@@ -124,12 +124,12 @@ void CarlaEngineOsc::sendPluginPortCount(const CarlaPlugin* const plugin) const
                 static_cast<int32_t>(plugin->getParameterCount()));
 }
 
-void CarlaEngineOsc::sendPluginParameterInfo(const CarlaPlugin* const plugin, const uint32_t index) const noexcept
+void CarlaEngineOsc::sendPluginParameterInfo(const CarlaPluginPtr& plugin, const uint32_t index) const noexcept
 {
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.path != nullptr && fControlDataTCP.path[0] != '\0',);
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.target != nullptr,);
     CARLA_SAFE_ASSERT_RETURN(plugin != nullptr,);
-    carla_debug("CarlaEngineOsc::sendPluginParameterInfo(%p, %u)", plugin, index);
+    carla_debug("CarlaEngineOsc::sendPluginParameterInfo(%p, %u)", plugin.get(), index);
 
     char bufName[STR_MAX+1], bufUnit[STR_MAX+1], bufComment[STR_MAX+1], bufGroupName[STR_MAX+1];
     carla_zeroChars(bufName, STR_MAX+1);
@@ -190,7 +190,7 @@ void CarlaEngineOsc::sendPluginParameterInfo(const CarlaPlugin* const plugin, co
                 static_cast<double>(paramRanges.stepLarge));
 }
 
-void CarlaEngineOsc::sendPluginDataCount(const CarlaPlugin* const plugin) const noexcept
+void CarlaEngineOsc::sendPluginDataCount(const CarlaPluginPtr& plugin) const noexcept
 {
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.path != nullptr && fControlDataTCP.path[0] != '\0',);
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.target != nullptr,);
@@ -209,7 +209,7 @@ void CarlaEngineOsc::sendPluginDataCount(const CarlaPlugin* const plugin) const
                 static_cast<int32_t>(plugin->getCurrentMidiProgram()));
 }
 
-void CarlaEngineOsc::sendPluginProgramCount(const CarlaPlugin* const plugin) const noexcept
+void CarlaEngineOsc::sendPluginProgramCount(const CarlaPluginPtr& plugin) const noexcept
 {
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.path != nullptr && fControlDataTCP.path[0] != '\0',);
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.target != nullptr,);
@@ -225,11 +225,11 @@ void CarlaEngineOsc::sendPluginProgramCount(const CarlaPlugin* const plugin) con
                 static_cast<int32_t>(plugin->getMidiProgramCount()));
 }
 
-void CarlaEngineOsc::sendPluginProgram(const CarlaPlugin* const plugin, const uint32_t index) const noexcept
+void CarlaEngineOsc::sendPluginProgram(const CarlaPluginPtr& plugin, const uint32_t index) const noexcept
 {
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.path != nullptr && fControlDataTCP.path[0] != '\0',);
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.target != nullptr,);
-    carla_stdout("CarlaEngineOsc::sendPluginProgram(%p, %u)", plugin, index);
+    carla_stdout("CarlaEngineOsc::sendPluginProgram(%p, %u)", plugin.get(), index);
 
     char strBuf[STR_MAX+1];
     carla_zeroChars(strBuf, STR_MAX+1);
@@ -243,11 +243,11 @@ void CarlaEngineOsc::sendPluginProgram(const CarlaPlugin* const plugin, const ui
                 static_cast<int32_t>(plugin->getId()), static_cast<int32_t>(index), strBuf);
 }
 
-void CarlaEngineOsc::sendPluginMidiProgram(const CarlaPlugin* const plugin, const uint32_t index) const noexcept
+void CarlaEngineOsc::sendPluginMidiProgram(const CarlaPluginPtr& plugin, const uint32_t index) const noexcept
 {
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.path != nullptr && fControlDataTCP.path[0] != '\0',);
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.target != nullptr,);
-    carla_stdout("CarlaEngineOsc::sendPluginProgram(%p, %u)", plugin, index);
+    carla_stdout("CarlaEngineOsc::sendPluginProgram(%p, %u)", plugin.get(), index);
 
     const MidiProgramData& mpdata(plugin->getMidiProgramData(index));
     CARLA_SAFE_ASSERT_RETURN(mpdata.name != nullptr,);
@@ -261,11 +261,11 @@ void CarlaEngineOsc::sendPluginMidiProgram(const CarlaPlugin* const plugin, cons
                 static_cast<int32_t>(mpdata.bank), static_cast<int32_t>(mpdata.program), mpdata.name);
 }
 
-void CarlaEngineOsc::sendPluginCustomData(const CarlaPlugin* const plugin, const uint32_t index) const noexcept
+void CarlaEngineOsc::sendPluginCustomData(const CarlaPluginPtr& plugin, const uint32_t index) const noexcept
 {
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.path != nullptr && fControlDataTCP.path[0] != '\0',);
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.target != nullptr,);
-    carla_stdout("CarlaEngineOsc::sendPluginCustomData(%p, %u)", plugin, index);
+    carla_stdout("CarlaEngineOsc::sendPluginCustomData(%p, %u)", plugin.get(), index);
 
     const CustomData& cdata(plugin->getCustomData(index));
     CARLA_SAFE_ASSERT_RETURN(cdata.isValid(),);
@@ -279,7 +279,7 @@ void CarlaEngineOsc::sendPluginCustomData(const CarlaPlugin* const plugin, const
                 cdata.type, cdata.key, cdata.value);
 }
 
-void CarlaEngineOsc::sendPluginInternalParameterValues(const CarlaPlugin* const plugin) const noexcept
+void CarlaEngineOsc::sendPluginInternalParameterValues(const CarlaPluginPtr& plugin) const noexcept
 {
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.path != nullptr && fControlDataTCP.path[0] != '\0',);
     CARLA_SAFE_ASSERT_RETURN(fControlDataTCP.target != nullptr,);

source/backend/engine/CarlaEnginePorts.hpp

@@ -36,7 +36,7 @@ struct CarlaEngineCVSourcePorts::ProtectedData {
     CarlaRecursiveMutex rmutex;
 #ifndef BUILD_BRIDGE_ALTERNATIVE_ARCH
     PatchbayGraph* graph;
-    CarlaPlugin* plugin;
+    CarlaPluginPtr plugin;
 #endif
     water::Array<CarlaEngineEventCV> cvs;
 
@@ -76,7 +76,7 @@ public:
     CarlaEngineCVSourcePortsForStandalone() : CarlaEngineCVSourcePorts() {}
     ~CarlaEngineCVSourcePortsForStandalone() override {}
 
-    inline void setGraphAndPlugin(PatchbayGraph* const graph, CarlaPlugin* const plugin) noexcept
+    inline void setGraphAndPlugin(PatchbayGraph* const graph, const CarlaPluginPtr plugin) noexcept
     {
         pData->graph = graph;
         pData->plugin = plugin;

source/backend/engine/CarlaEngineThread.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla Plugin Host
- * Copyright (C) 2011-2019 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2011-2020 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
@@ -73,7 +73,7 @@ void CarlaEngineThread::run() noexcept
 
         for (uint i=0, count = kEngine->getCurrentPluginCount(); i < count; ++i)
         {
-            CarlaPlugin* const plugin(kEngine->getPluginUnchecked(i));
+            const CarlaPluginPtr plugin = kEngine->getPluginUnchecked(i);
 
             CARLA_SAFE_ASSERT_CONTINUE(plugin != nullptr && plugin->isEnabled());
             CARLA_SAFE_ASSERT_UINT2(i == plugin->getId(), i, plugin->getId());

source/backend/plugin/CarlaPlugin.cpp

@@ -2547,6 +2547,15 @@ void CarlaPlugin::restoreLV2State() noexcept
     carla_stderr2("Warning: restoreLV2State() called for non-implemented type");
 }
 
+void CarlaPlugin::prepareForDeletion() noexcept
+{
+    carla_debug("CarlaPlugin::prepareForDeletion");
+
+    const CarlaMutexLocker cml(pData->masterMutex);
+
+    pData->client->deactivate(true);
+}
+
 void CarlaPlugin::waitForBridgeSaveSignal() noexcept
 {
 }
@@ -2571,7 +2580,7 @@ CarlaPlugin::ScopedDisabler::ScopedDisabler(CarlaPlugin* const plugin) noexcept
         plugin->pData->enabled = false;
 
         if (plugin->pData->client->isActive())
-            plugin->pData->client->deactivate();
+            plugin->pData->client->deactivate(false);
     }
 }
 

source/backend/plugin/CarlaPluginAU.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla AU Plugin
- * Copyright (C) 2014 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2014-2020 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
@@ -23,9 +23,10 @@ CARLA_BACKEND_START_NAMESPACE
 
 // -------------------------------------------------------------------------------------------------------------------
 
-CarlaPlugin* CarlaPlugin::newAU(const Initializer& init)
+CarlaPluginPtr CarlaPlugin::newAU(const Initializer& init)
 {
-    carla_debug("CarlaPlugin::newAU({%p, \"%s\", \"%s\", \"%s\", " P_INT64 "})", init.engine, init.filename, init.name, init.label, init.uniqueId);
+    carla_debug("CarlaPlugin::newAU({%p, \"%s\", \"%s\", \"%s\", " P_INT64 "})",
+                init.engine, init.filename, init.name, init.label, init.uniqueId);
 
 #if defined(CARLA_OS_MAC)
     return newJuce(init, "AU");

source/backend/plugin/CarlaPluginBridge.cpp

@@ -424,7 +424,7 @@ public:
         pData->masterMutex.lock();
 
         if (pData->client != nullptr && pData->client->isActive())
-            pData->client->deactivate();
+            pData->client->deactivate(true);
 
         if (pData->active)
         {
@@ -2469,7 +2469,8 @@ public:
 
     // -------------------------------------------------------------------
 
-    bool init(const char* const filename,
+    bool init(CarlaPluginPtr plugin,
+              const char* const filename,
               const char* const name,
               const char* const label,
               const int64_t uniqueId,
@@ -2600,7 +2601,7 @@ public:
                 pData->name = pData->engine->getUniquePluginName("unknown");
         }
 
-        pData->client = pData->engine->addClient(this);
+        pData->client = pData->engine->addClient(plugin);
 
         if (pData->client == nullptr || ! pData->client->isOk())
         {
@@ -3047,9 +3048,12 @@ CARLA_BACKEND_END_NAMESPACE
 
 CARLA_BACKEND_START_NAMESPACE
 
-CarlaPlugin* CarlaPlugin::newBridge(const Initializer& init, BinaryType btype, PluginType ptype, const char* bridgeBinary)
+CarlaPluginPtr CarlaPlugin::newBridge(const Initializer& init,
+                                      BinaryType btype, PluginType ptype, const char* bridgeBinary)
 {
-    carla_debug("CarlaPlugin::newBridge({%p, \"%s\", \"%s\", \"%s\"}, %s, %s, \"%s\")", init.engine, init.filename, init.name, init.label, BinaryType2Str(btype), PluginType2Str(ptype), bridgeBinary);
+    carla_debug("CarlaPlugin::newBridge({%p, \"%s\", \"%s\", \"%s\"}, %s, %s, \"%s\")",
+                init.engine, init.filename, init.name, init.label,
+                BinaryType2Str(btype), PluginType2Str(ptype), bridgeBinary);
 
     if (bridgeBinary == nullptr || bridgeBinary[0] == '\0')
     {
@@ -3063,13 +3067,10 @@ CarlaPlugin* CarlaPlugin::newBridge(const Initializer& init, BinaryType btype, P
         ++bridgeBinary;
 #endif
 
-    CarlaPluginBridge* const plugin(new CarlaPluginBridge(init.engine, init.id, btype, ptype));
+    std::shared_ptr<CarlaPluginBridge> plugin(new CarlaPluginBridge(init.engine, init.id, btype, ptype));
 
-    if (! plugin->init(init.filename, init.name, init.label, init.uniqueId, init.options, bridgeBinary))
-    {
-        delete plugin;
+    if (! plugin->init(plugin, init.filename, init.name, init.label, init.uniqueId, init.options, bridgeBinary))
         return nullptr;
-    }
 
     return plugin;
 }

source/backend/plugin/CarlaPluginFluidSynth.cpp

@@ -118,7 +118,7 @@ public:
         pData->masterMutex.lock();
 
         if (pData->client != nullptr && pData->client->isActive())
-            pData->client->deactivate();
+            pData->client->deactivate(true);
 
         if (pData->active)
         {
@@ -1655,7 +1655,8 @@ public:
 
     // -------------------------------------------------------------------
 
-    bool init(const char* const filename, const char* const name, const char* const label, const uint options)
+    bool init(const CarlaPluginPtr plugin,
+              const char* const filename, const char* const name, const char* const label, const uint options)
     {
         CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr, false);
 
@@ -1723,7 +1724,7 @@ public:
         // ---------------------------------------------------------------
         // register client
 
-        pData->client = pData->engine->addClient(this);
+        pData->client = pData->engine->addClient(plugin);
 
         if (pData->client == nullptr || ! pData->client->isOk())
         {
@@ -1872,7 +1873,7 @@ CARLA_BACKEND_START_NAMESPACE
 
 // -------------------------------------------------------------------------------------------------------------------
 
-CarlaPlugin* CarlaPlugin::newFluidSynth(const Initializer& init, PluginType ptype, bool use16Outs)
+CarlaPluginPtr CarlaPlugin::newFluidSynth(const Initializer& init, PluginType ptype, bool use16Outs)
 {
     carla_debug("CarlaPlugin::newFluidSynth({%p, \"%s\", \"%s\", \"%s\", " P_INT64 "}, %s)",
                 init.engine, init.filename, init.name, init.label, init.uniqueId, bool2str(use16Outs));
@@ -1899,13 +1900,10 @@ CarlaPlugin* CarlaPlugin::newFluidSynth(const Initializer& init, PluginType ptyp
     }
 #endif
 
-    CarlaPluginFluidSynth* const plugin(new CarlaPluginFluidSynth(init.engine, init.id,  use16Outs));
+    std::shared_ptr<CarlaPluginFluidSynth> plugin(new CarlaPluginFluidSynth(init.engine, init.id,  use16Outs));
 
-    if (! plugin->init(init.filename, init.name, init.label, init.options))
-    {
-        delete plugin;
+    if (! plugin->init(plugin, init.filename, init.name, init.label, init.options))
         return nullptr;
-    }
 
     return plugin;
 #else

source/backend/plugin/CarlaPluginInternal.cpp

@@ -722,7 +722,7 @@ CarlaPlugin::ProtectedData::~ProtectedData() noexcept
         {
             // must not happen
             carla_safe_assert("client->isActive()", __FILE__, __LINE__);
-            client->deactivate();
+            client->deactivate(true);
         }
 
         clearBuffers();

source/backend/plugin/CarlaPluginJack.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla Plugin JACK
- * Copyright (C) 2016-2019 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2016-2020 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
@@ -504,7 +504,7 @@ public:
         pData->masterMutex.lock();
 
         if (pData->client != nullptr && pData->client->isActive())
-            pData->client->deactivate();
+            pData->client->deactivate(true);
 
         if (pData->active)
         {
@@ -1514,7 +1514,8 @@ public:
 
     // -------------------------------------------------------------------
 
-    bool init(const char* const filename, const char* const name, const char* const label)
+    bool init(const CarlaPluginPtr plugin,
+              const char* const filename, const char* const name, const char* const label)
     {
         CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr, false);
 
@@ -1657,7 +1658,7 @@ public:
         if (pData->name == nullptr)
             pData->name = pData->engine->getUniquePluginName("unknown");
 
-        pData->client = pData->engine->addClient(this);
+        pData->client = pData->engine->addClient(plugin);
 
         if (pData->client == nullptr || ! pData->client->isOk())
         {
@@ -1922,18 +1923,15 @@ CARLA_BACKEND_END_NAMESPACE
 
 CARLA_BACKEND_START_NAMESPACE
 
-CarlaPlugin* CarlaPlugin::newJackApp(const Initializer& init)
+CarlaPluginPtr CarlaPlugin::newJackApp(const Initializer& init)
 {
     carla_debug("CarlaPlugin::newJackApp({%p, \"%s\", \"%s\", \"%s\"})", init.engine, init.filename, init.name, init.label);
 
 #ifdef CARLA_OS_LINUX
-    CarlaPluginJack* const plugin(new CarlaPluginJack(init.engine, init.id));
+    std::shared_ptr<CarlaPluginJack> plugin(new CarlaPluginJack(init.engine, init.id));
 
-    if (! plugin->init(init.filename, init.name, init.label))
-    {
-        delete plugin;
+    if (! plugin->init(plugin, init.filename, init.name, init.label))
         return nullptr;
-    }
 
     return plugin;
 #else

source/backend/plugin/CarlaPluginJuce.cpp

@@ -89,7 +89,7 @@ public:
         pData->masterMutex.lock();
 
         if (pData->client != nullptr && pData->client->isActive())
-            pData->client->deactivate();
+            pData->client->deactivate(true);
 
         if (pData->active)
         {
@@ -1248,7 +1248,9 @@ protected:
     // -------------------------------------------------------------------
 
 public:
-    bool init(const char* const filename, const char* const name, const char* const label, const int64_t uniqueId, const uint options, const char* const format)
+    bool init(const CarlaPluginPtr plugin,
+              const char* const filename, const char* const name, const char* const label,
+              const int64_t uniqueId, const uint options, const char* const format)
     {
         CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr, false);
 
@@ -1386,7 +1388,7 @@ public:
         // ---------------------------------------------------------------
         // register client
 
-        pData->client = pData->engine->addClient(this);
+        pData->client = pData->engine->addClient(plugin);
 
         if (pData->client == nullptr || ! pData->client->isOk())
         {
@@ -1482,18 +1484,16 @@ CARLA_BACKEND_END_NAMESPACE
 
 CARLA_BACKEND_START_NAMESPACE
 
-CarlaPlugin* CarlaPlugin::newJuce(const Initializer& init, const char* const format)
+CarlaPluginPtr CarlaPlugin::newJuce(const Initializer& init, const char* const format)
 {
-    carla_debug("CarlaPlugin::newJuce({%p, \"%s\", \"%s\", \"%s\", " P_INT64 "}, %s)", init.engine, init.filename, init.name, init.label, init.uniqueId, format);
+    carla_debug("CarlaPlugin::newJuce({%p, \"%s\", \"%s\", \"%s\", " P_INT64 "}, %s)",
+                init.engine, init.filename, init.name, init.label, init.uniqueId, format);
 
 #ifdef USING_JUCE
-    CarlaPluginJuce* const plugin(new CarlaPluginJuce(init.engine, init.id));
+    std::shared_ptr<CarlaPluginJuce> plugin(new CarlaPluginJuce(init.engine, init.id));
 
-    if (! plugin->init(init.filename, init.name, init.label, init.uniqueId, init.options, format))
-    {
-        delete plugin;
+    if (! plugin->init(plugin, init.filename, init.name, init.label, init.uniqueId, init.options, format))
         return nullptr;
-    }
 
     return plugin;
 #else

source/backend/plugin/CarlaPluginLADSPADSSI.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla Plugin, LADSPA/DSSI implementation
- * Copyright (C) 2011-2019 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2011-2020 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
@@ -326,7 +326,7 @@ public:
         pData->masterMutex.lock();
 
         if (pData->client != nullptr && pData->client->isActive())
-            pData->client->deactivate();
+            pData->client->deactivate(true);
 
         if (pData->active)
         {
@@ -2657,7 +2657,8 @@ public:
 
     // -------------------------------------------------------------------
 
-    bool initLADSPA(const char* const filename, const char* name, const char* const label, const uint options,
+    bool initLADSPA(const CarlaPluginPtr plugin,
+                    const char* const filename, const char* name, const char* const label, const uint options,
                     const LADSPA_RDF_Descriptor* const rdfDescriptor)
     {
         CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr, false);
@@ -2740,10 +2741,11 @@ public:
             return false;
         }
 
-        return init2(filename, name, options, rdfDescriptor);
+        return init2(plugin, filename, name, options, rdfDescriptor);
     }
 
-    bool initDSSI(const char* const filename, const char* name, const char* const label, const uint options)
+    bool initDSSI(const CarlaPluginPtr plugin,
+                  const char* const filename, const char* name, const char* const label, const uint options)
     {
         CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr, false);
 
@@ -2845,10 +2847,11 @@ public:
             return false;
         }
 
-        return init2(filename, name, options, nullptr);
+        return init2(plugin, filename, name, options, nullptr);
     }
 
-    bool init2(const char* const filename, const char* name, const uint options,
+    bool init2(const CarlaPluginPtr plugin,
+               const char* const filename, const char* name, const uint options,
                const LADSPA_RDF_Descriptor* const rdfDescriptor)
     {
         // ---------------------------------------------------------------
@@ -2885,7 +2888,7 @@ public:
         // ---------------------------------------------------------------
         // register client
 
-        pData->client = pData->engine->addClient(this);
+        pData->client = pData->engine->addClient(plugin);
 
         if (pData->client == nullptr || ! pData->client->isOk())
         {
@@ -3126,34 +3129,28 @@ private:
 
 // -------------------------------------------------------------------------------------------------------------------
 
-CarlaPlugin* CarlaPlugin::newLADSPA(const Initializer& init, const LADSPA_RDF_Descriptor* const rdfDescriptor)
+CarlaPluginPtr CarlaPlugin::newLADSPA(const Initializer& init, const LADSPA_RDF_Descriptor* const rdfDescriptor)
 {
     carla_debug("CarlaPlugin::newLADSPA({%p, \"%s\", \"%s\", \"%s\", " P_INT64 ", %x}, %p)",
                 init.engine, init.filename, init.name, init.label, init.uniqueId, init.options, rdfDescriptor);
 
-    CarlaPluginLADSPADSSI* const plugin(new CarlaPluginLADSPADSSI(init.engine, init.id));
+    std::shared_ptr<CarlaPluginLADSPADSSI> plugin(new CarlaPluginLADSPADSSI(init.engine, init.id));
 
-    if (! plugin->initLADSPA(init.filename, init.name, init.label, init.options, rdfDescriptor))
-    {
-        delete plugin;
+    if (! plugin->initLADSPA(plugin, init.filename, init.name, init.label, init.options, rdfDescriptor))
         return nullptr;
-    }
 
     return plugin;
 }
 
-CarlaPlugin* CarlaPlugin::newDSSI(const Initializer& init)
+CarlaPluginPtr CarlaPlugin::newDSSI(const Initializer& init)
 {
     carla_debug("CarlaPlugin::newDSSI({%p, \"%s\", \"%s\", \"%s\", " P_INT64 ", %x})",
                 init.engine, init.filename, init.name, init.label, init.uniqueId, init.options);
 
-    CarlaPluginLADSPADSSI* const plugin(new CarlaPluginLADSPADSSI(init.engine, init.id));
+    std::shared_ptr<CarlaPluginLADSPADSSI> plugin(new CarlaPluginLADSPADSSI(init.engine, init.id));
 
-    if (! plugin->initDSSI(init.filename, init.name, init.label, init.options))
-    {
-        delete plugin;
+    if (! plugin->initDSSI(plugin, init.filename, init.name, init.label, init.options))
         return nullptr;
-    }
 
     return plugin;
 }

source/backend/plugin/CarlaPluginLV2.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla LV2 Plugin
- * Copyright (C) 2011-2019 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2011-2020 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
@@ -683,7 +683,7 @@ public:
         pData->masterMutex.lock();
 
         if (pData->client != nullptr && pData->client->isActive())
-            pData->client->deactivate();
+            pData->client->deactivate(true);
 
         if (pData->active)
         {
@@ -5321,7 +5321,7 @@ public:
         fInlineDisplayNeedsRedraw = true;
     }
 
-    const LV2_Inline_Display_Image_Surface* renderInlineDisplay(const uint32_t width, const uint32_t height)
+    const LV2_Inline_Display_Image_Surface* renderInlineDisplay(const uint32_t width, const uint32_t height) const
     {
         CARLA_SAFE_ASSERT_RETURN(fExt.inlineDisplay != nullptr && fExt.inlineDisplay->render != nullptr, nullptr);
         CARLA_SAFE_ASSERT_RETURN(width > 0, nullptr);
@@ -5640,7 +5640,8 @@ public:
     // -------------------------------------------------------------------
 
 public:
-    bool init(const char* const name, const char* const uri, const uint options)
+    bool init(const CarlaPluginPtr plugin,
+              const char* const name, const char* const uri, const uint options)
     {
         CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr, false);
 
@@ -5828,7 +5829,7 @@ public:
         // ---------------------------------------------------------------
         // register client
 
-        pData->client = pData->engine->addClient(this);
+        pData->client = pData->engine->addClient(plugin);
 
         if (pData->client == nullptr || ! pData->client->isOk())
         {
@@ -7380,27 +7381,25 @@ bool CarlaPipeServerLV2::msgReceived(const char* const msg) noexcept
 
 // -------------------------------------------------------------------------------------------------------------------
 
-CarlaPlugin* CarlaPlugin::newLV2(const Initializer& init)
+CarlaPluginPtr CarlaPlugin::newLV2(const Initializer& init)
 {
-    carla_debug("CarlaPlugin::newLV2({%p, \"%s\", \"%s\", " P_INT64 "})", init.engine, init.name, init.label, init.uniqueId);
+    carla_debug("CarlaPlugin::newLV2({%p, \"%s\", \"%s\", " P_INT64 "})",
+                init.engine, init.name, init.label, init.uniqueId);
 
-    CarlaPluginLV2* const plugin(new CarlaPluginLV2(init.engine, init.id));
+    std::shared_ptr<CarlaPluginLV2> plugin(new CarlaPluginLV2(init.engine, init.id));
 
-    if (! plugin->init(init.name, init.label, init.options))
-    {
-        delete plugin;
+    if (! plugin->init(plugin, init.name, init.label, init.options))
         return nullptr;
-    }
 
     return plugin;
 }
 
 // used in CarlaStandalone.cpp
-const void* carla_render_inline_display_lv2(CarlaPlugin* plugin, uint32_t width, uint32_t height);
+const void* carla_render_inline_display_lv2(const CarlaPluginPtr& plugin, uint32_t width, uint32_t height);
 
-const void* carla_render_inline_display_lv2(CarlaPlugin* plugin, uint32_t width, uint32_t height)
+const void* carla_render_inline_display_lv2(const CarlaPluginPtr& plugin, uint32_t width, uint32_t height)
 {
-    CarlaPluginLV2* const lv2Plugin = (CarlaPluginLV2*)plugin;
+    const std::shared_ptr<CarlaPluginLV2>& lv2Plugin((const std::shared_ptr<CarlaPluginLV2>&)plugin);
 
     return lv2Plugin->renderInlineDisplay(width, height);
 }

source/backend/plugin/CarlaPluginNative.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla Native Plugin
- * Copyright (C) 2012-2019 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2012-2020 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
@@ -312,7 +312,7 @@ public:
         pData->masterMutex.lock();
 
         if (pData->client != nullptr && pData->client->isActive())
-            pData->client->deactivate();
+            pData->client->deactivate(true);
 
         CARLA_ASSERT(! fIsProcessing);
 
@@ -2620,7 +2620,7 @@ public:
 
     // -------------------------------------------------------------------
 
-    const NativeInlineDisplayImageSurface* renderInlineDisplay(const uint32_t width, const uint32_t height)
+    const NativeInlineDisplayImageSurface* renderInlineDisplay(const uint32_t width, const uint32_t height) const
     {
         CARLA_SAFE_ASSERT_RETURN(fDescriptor->hints & NATIVE_PLUGIN_HAS_INLINE_DISPLAY, nullptr);
         CARLA_SAFE_ASSERT_RETURN(fDescriptor->render_inline_display, nullptr);
@@ -2774,7 +2774,8 @@ public:
 
     // -------------------------------------------------------------------
 
-    bool init(const char* const name, const char* const label, const uint options)
+    bool init(const CarlaPluginPtr plugin,
+              const char* const name, const char* const label, const uint options)
     {
         CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr, false);
 
@@ -2859,7 +2860,7 @@ public:
         // ---------------------------------------------------------------
         // register client
 
-        pData->client = pData->engine->addClient(this);
+        pData->client = pData->engine->addClient(plugin);
 
         if (pData->client == nullptr || ! pData->client->isOk())
         {
@@ -3037,27 +3038,25 @@ private:
 
 // -----------------------------------------------------------------------
 
-CarlaPlugin* CarlaPlugin::newNative(const Initializer& init)
+CarlaPluginPtr CarlaPlugin::newNative(const Initializer& init)
 {
-    carla_debug("CarlaPlugin::newNative({%p, \"%s\", \"%s\", \"%s\", " P_INT64 "})", init.engine, init.filename, init.name, init.label, init.uniqueId);
+    carla_debug("CarlaPlugin::newNative({%p, \"%s\", \"%s\", \"%s\", " P_INT64 "})",
+                init.engine, init.filename, init.name, init.label, init.uniqueId);
 
-    CarlaPluginNative* const plugin(new CarlaPluginNative(init.engine, init.id));
+    std::shared_ptr<CarlaPluginNative> plugin(new CarlaPluginNative(init.engine, init.id));
 
-    if (! plugin->init(init.name, init.label, init.options))
-    {
-        delete plugin;
+    if (! plugin->init(plugin, init.name, init.label, init.options))
         return nullptr;
-    }
 
     return plugin;
 }
 
 // used in CarlaStandalone.cpp
-const void* carla_render_inline_display_internal(CarlaPlugin* plugin, uint32_t width, uint32_t height);
+const void* carla_render_inline_display_internal(const CarlaPluginPtr& plugin, uint32_t width, uint32_t height);
 
-const void* carla_render_inline_display_internal(CarlaPlugin* plugin, uint32_t  width, uint32_t height)
+const void* carla_render_inline_display_internal(const CarlaPluginPtr& plugin, uint32_t  width, uint32_t height)
 {
-    CarlaPluginNative* const nativePlugin = (CarlaPluginNative*)plugin;
+    const std::shared_ptr<CarlaPluginNative>& nativePlugin((const std::shared_ptr<CarlaPluginNative>&)plugin);
 
     return nativePlugin->renderInlineDisplay(width, height);
 }

source/backend/plugin/CarlaPluginSFZero.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla SFZero Plugin
- * Copyright (C) 2018-2019 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2018-2020 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
@@ -68,7 +68,7 @@ public:
         pData->masterMutex.lock();
 
         if (pData->client != nullptr && pData->client->isActive())
-            pData->client->deactivate();
+            pData->client->deactivate(true);
 
         if (pData->active)
         {
@@ -662,7 +662,8 @@ public:
 
     // -------------------------------------------------------------------
 
-    bool init(const char* const filename, const char* const name, const char* const label, const uint options)
+    bool init(const CarlaPluginPtr plugin,
+              const char* const filename, const char* const name, const char* const label, const uint options)
     {
         CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr, false);
 
@@ -729,7 +730,7 @@ public:
         // ---------------------------------------------------------------
         // register client
 
-        pData->client = pData->engine->addClient(this);
+        pData->client = pData->engine->addClient(plugin);
 
         if (pData->client == nullptr || ! pData->client->isOk())
         {
@@ -770,7 +771,7 @@ private:
 
 // -------------------------------------------------------------------------------------------------------------------
 
-CarlaPlugin* CarlaPlugin::newSFZero(const Initializer& init)
+CarlaPluginPtr CarlaPlugin::newSFZero(const Initializer& init)
 {
     carla_debug("CarlaPluginSFZero::newSFZero({%p, \"%s\", \"%s\", \"%s\", " P_INT64 "})",
                 init.engine, init.filename, init.name, init.label, init.uniqueId);
@@ -784,13 +785,10 @@ CarlaPlugin* CarlaPlugin::newSFZero(const Initializer& init)
         return nullptr;
     }
 
-    CarlaPluginSFZero* const plugin(new CarlaPluginSFZero(init.engine, init.id));
+    std::shared_ptr<CarlaPluginSFZero> plugin(new CarlaPluginSFZero(init.engine, init.id));
 
-    if (! plugin->init(init.filename, init.name, init.label, init.options))
-    {
-        delete plugin;
+    if (! plugin->init(plugin, init.filename, init.name, init.label, init.options))
         return nullptr;
-    }
 
     return plugin;
 }

source/backend/plugin/CarlaPluginVST2.cpp

@@ -128,7 +128,7 @@ public:
         pData->masterMutex.lock();
 
         if (pData->client != nullptr && pData->client->isActive())
-            pData->client->deactivate();
+            pData->client->deactivate(true);
 
         CARLA_ASSERT(! fIsProcessing);
 
@@ -2357,7 +2357,8 @@ protected:
     // -------------------------------------------------------------------
 
 public:
-    bool init(const char* const filename, const char* const name, const int64_t uniqueId, const uint options)
+    bool init(const CarlaPluginPtr plugin,
+              const char* const filename, const char* const name, const int64_t uniqueId, const uint options)
     {
         CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr, false);
 
@@ -2564,7 +2565,7 @@ public:
         // ---------------------------------------------------------------
         // register client
 
-        pData->client = pData->engine->addClient(this);
+        pData->client = pData->engine->addClient(plugin);
 
         if (pData->client == nullptr || ! pData->client->isOk())
         {
@@ -2864,22 +2865,20 @@ CARLA_BACKEND_END_NAMESPACE
 
 CARLA_BACKEND_START_NAMESPACE
 
-CarlaPlugin* CarlaPlugin::newVST2(const Initializer& init)
+CarlaPluginPtr CarlaPlugin::newVST2(const Initializer& init)
 {
-    carla_debug("CarlaPlugin::newVST2({%p, \"%s\", \"%s\", " P_INT64 "})", init.engine, init.filename, init.name, init.uniqueId);
+    carla_debug("CarlaPlugin::newVST2({%p, \"%s\", \"%s\", " P_INT64 "})",
+                init.engine, init.filename, init.name, init.uniqueId);
 
 #ifdef USE_JUCE_FOR_VST2
     if (std::getenv("CARLA_DO_NOT_USE_JUCE_FOR_VST2") == nullptr)
         return newJuce(init, "VST2");
 #endif
 
-    CarlaPluginVST2* const plugin(new CarlaPluginVST2(init.engine, init.id));
+    std::shared_ptr<CarlaPluginVST2> plugin(new CarlaPluginVST2(init.engine, init.id));
 
-    if (! plugin->init(init.filename, init.name, init.uniqueId, init.options))
-    {
-        delete plugin;
+    if (! plugin->init(plugin, init.filename, init.name, init.uniqueId, init.options))
         return nullptr;
-    }
 
     return plugin;
 }

source/backend/plugin/CarlaPluginVST3.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla VST3 Plugin
- * Copyright (C) 2014 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2014-2020 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
@@ -23,9 +23,10 @@ CARLA_BACKEND_START_NAMESPACE
 
 // -------------------------------------------------------------------------------------------------------------------
 
-CarlaPlugin* CarlaPlugin::newVST3(const Initializer& init)
+CarlaPluginPtr CarlaPlugin::newVST3(const Initializer& init)
 {
-    carla_debug("CarlaPlugin::newVST3({%p, \"%s\", \"%s\", " P_INT64 "})", init.engine, init.filename, init.name, init.uniqueId);
+    carla_debug("CarlaPlugin::newVST3({%p, \"%s\", \"%s\", " P_INT64 "})",
+                init.engine, init.filename, init.name, init.uniqueId);
 
 #ifdef USING_JUCE
     return newJuce(init, "VST3");

source/bridges-plugin/CarlaBridgeSingleLV2.cpp

@@ -1,6 +1,6 @@
 /*
  * Carla LV2 Single Plugin
- * Copyright (C) 2017-2019 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2017-2020 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
@@ -145,6 +145,8 @@ public:
         if (fPlugin != nullptr && fIsActive)
             fPlugin->setActive(false, false, false);
 
+        fPlugin = nullptr;
+
         close();
     }
 
@@ -496,7 +498,7 @@ protected:
     // ----------------------------------------------------------------------------------------------------------------
 
 private:
-    CarlaPlugin* fPlugin;
+    std::shared_ptr<CarlaPlugin> fPlugin;
     CarlaString fUiName;
 
 #ifdef USING_JUCE