Implement Extension Loader

* Extensions are now scanned and loaded on demand.
* Extensions found are cached into a file that is used to load them (which is also exported).
* Editor will ask to restart when an extension requires core functionality.
* Editor will attempt to load extensions always before importing or loading scenes. This ensures extensions can register the relevant types.

4 files changed, 26 insertions, 0 deletions

diff --git a/core/extension/native_extension.cpp b/core/extension/native_extension.cpp
index 0556c9c84d..a3cd7ca14c 100644
--- a/core/extension/native_extension.cpp
+++ b/core/extension/native_extension.cpp
@@ -35,6 +35,8 @@
 #include "core/object/method_bind.h"
 #include "core/os/os.h"
 
+const char *NativeExtension::EXTENSION_LIST_CONFIG_FILE = "res://.godot/extension_list.cfg";
+
 class NativeExtensionMethodBind : public MethodBind {
 	GDNativeExtensionClassMethodCall call_func;
 	GDNativeExtensionClassMethodPtrCall ptrcall_func;
diff --git a/core/extension/native_extension.h b/core/extension/native_extension.h
index a961b21cc9..b661381d64 100644
--- a/core/extension/native_extension.h
+++ b/core/extension/native_extension.h
@@ -60,6 +60,8 @@ protected:
 	static void _bind_methods();
 
 public:
+	static const char *EXTENSION_LIST_CONFIG_FILE;
+
 	Error open_library(const String &p_path, const String &p_entry_symbol);
 	void close_library();
 
diff --git a/core/extension/native_extension_manager.cpp b/core/extension/native_extension_manager.cpp
index 7be2593845..8b7a9df4f1 100644
--- a/core/extension/native_extension_manager.cpp
+++ b/core/extension/native_extension_manager.cpp
@@ -29,6 +29,7 @@
 /*************************************************************************/
 
 #include "native_extension_manager.h"
+#include "core/io/file_access.h"
 
 NativeExtensionManager::LoadStatus NativeExtensionManager::load_extension(const String &p_path) {
 	if (native_extension_map.has(p_path)) {
@@ -76,6 +77,11 @@ NativeExtensionManager::LoadStatus NativeExtensionManager::unload_extension(cons
 	native_extension_map.erase(p_path);
 	return LOAD_STATUS_OK;
 }
+
+bool NativeExtensionManager::is_extension_loaded(const String &p_path) const {
+	return native_extension_map.has(p_path);
+}
+
 Vector<String> NativeExtensionManager::get_loaded_extensions() const {
 	Vector<String> ret;
 	for (const Map<String, Ref<NativeExtension>>::Element *E = native_extension_map.front(); E; E = E->next()) {
@@ -105,6 +111,17 @@ void NativeExtensionManager::deinitialize_extensions(NativeExtension::Initializa
 	level = int32_t(p_level) - 1;
 }
 
+void NativeExtensionManager::load_extensions() {
+	FileAccessRef f = FileAccess::open(NativeExtension::EXTENSION_LIST_CONFIG_FILE, FileAccess::READ);
+	while (f && !f->eof_reached()) {
+		String s = f->get_line().strip_edges();
+		if (s != String()) {
+			LoadStatus err = load_extension(s);
+			ERR_CONTINUE_MSG(err == LOAD_STATUS_FAILED, "Error loading extension: " + s);
+		}
+	}
+}
+
 NativeExtensionManager *NativeExtensionManager::get_singleton() {
 	return singleton;
 }
@@ -112,6 +129,8 @@ void NativeExtensionManager::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("load_extension", "path"), &NativeExtensionManager::load_extension);
 	ClassDB::bind_method(D_METHOD("reload_extension", "path"), &NativeExtensionManager::reload_extension);
 	ClassDB::bind_method(D_METHOD("unload_extension", "path"), &NativeExtensionManager::unload_extension);
+	ClassDB::bind_method(D_METHOD("is_extension_loaded", "path"), &NativeExtensionManager::is_extension_loaded);
+
 	ClassDB::bind_method(D_METHOD("get_loaded_extensions"), &NativeExtensionManager::get_loaded_extensions);
 	ClassDB::bind_method(D_METHOD("get_extension", "path"), &NativeExtensionManager::get_extension);
 
diff --git a/core/extension/native_extension_manager.h b/core/extension/native_extension_manager.h
index 78465bd5cf..89ccd155fe 100644
--- a/core/extension/native_extension_manager.h
+++ b/core/extension/native_extension_manager.h
@@ -55,6 +55,7 @@ public:
 	LoadStatus load_extension(const String &p_path);
 	LoadStatus reload_extension(const String &p_path);
 	LoadStatus unload_extension(const String &p_path);
+	bool is_extension_loaded(const String &p_path) const;
 	Vector<String> get_loaded_extensions() const;
 	Ref<NativeExtension> get_extension(const String &p_path);
 
@@ -63,6 +64,8 @@ public:
 
 	static NativeExtensionManager *get_singleton();
 
+	void load_extensions();
+
 	NativeExtensionManager();
 };