core_reloadmodule Allow modules to save and restore their own data when reloading another mod

1 files changed, 80 insertions, 0 deletions

diff --git a/include/modules/reload.h b/include/modules/reload.h
new file mode 100644
index 000000000..6ee30c45e
--- /dev/null
+++ b/include/modules/reload.h
@@ -0,0 +1,80 @@
+/*
+ * InspIRCd -- Internet Relay Chat Daemon
+ *
+ *   Copyright (C) 2015 Attila Molnar <attilamolnar@hush.com>
+ *
+ * This file is part of InspIRCd.  InspIRCd is free software: you can
+ * redistribute it and/or modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#pragma once
+
+#include "event.h"
+
+namespace ReloadModule
+{
+	class EventListener;
+	class DataKeeper;
+
+	/** Container for data saved by modules before another module is reloaded.
+	 */
+	class CustomData
+	{
+		struct Data
+		{
+			EventListener* handler;
+			void* data;
+			Data(EventListener* Handler, void* moddata) : handler(Handler), data(moddata) { }
+		};
+		typedef std::vector<Data> List;
+		List list;
+
+	 public:
+		/** Add data to the saved state of a module.
+		 * The provided handler's OnReloadModuleRestore() method will be called when the reload is done with the pointer
+		 * provided.
+		 * @param handler Handler for restoring the data
+		 * @param data Pointer to the data, will be passed back to the provided handler's OnReloadModuleRestore() after the
+		 * reload finishes
+		 */
+		void add(EventListener* handler, void* data)
+		{
+			list.push_back(Data(handler, data));
+		}
+
+		friend class DataKeeper;
+	};
+
+	class EventListener : public Events::ModuleEventListener
+	{
+	 public:
+		EventListener(Module* mod)
+			: ModuleEventListener(mod, "event/reloadmodule")
+		{
+		}
+
+		/** Called whenever a module is about to be reloaded. Use this event to save data related to the module that you want
+		 * to be restored after the reload.
+		 * @param mod Module to be reloaded
+		 * @param cd CustomData instance that can store your data once.
+		 */
+		virtual void OnReloadModuleSave(Module* mod, CustomData& cd) = 0;
+
+		/** Restore data after a reload. Only called if data was added in OnReloadModuleSave().
+		 * @param mod Reloaded module
+		 * @param data Pointer that was passed to CustomData::add() in OnReloadModuleSave() at the time when the module's state
+		 * was saved
+		 */
+		virtual void OnReloadModuleRestore(Module* mod, void* data) = 0;
+	};
+}