/** * @file lllivefile.h * @brief Automatically reloads a file whenever it changes or is removed. * * $LicenseInfo:firstyear=2006&license=viewergpl$ * * Copyright (c) 2006-2009, Linden Research, Inc. * * Second Life Viewer Source Code * The source code in this file ("Source Code") is provided by Linden Lab * to you under the terms of the GNU General Public License, version 2.0 * ("GPL"), unless you have obtained a separate licensing agreement * ("Other License"), formally executed by you and Linden Lab. Terms of * the GPL can be found in doc/GPL-license.txt in this distribution, or * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2 * * There are special exceptions to the terms and conditions of the GPL as * it is applied to this Source Code. View the full text of the exception * in the file doc/FLOSS-exception.txt in this software distribution, or * online at * http://secondlifegrid.net/programs/open_source/licensing/flossexception * * By copying, modifying or distributing this software, you acknowledge * that you have read and understood your obligations described above, * and agree to abide by those obligations. * * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY, * COMPLETENESS OR PERFORMANCE. * $/LicenseInfo$ */ #ifndef LL_LLLIVEFILE_H #define LL_LLLIVEFILE_H extern const F32 DEFAULT_CONFIG_FILE_REFRESH; class LL_COMMON_API LLLiveFile { public: LLLiveFile(const std::string& filename, const F32 refresh_period = 5.f); virtual ~LLLiveFile(); /** * @brief Check to see if this live file should reload. * * Call this before using anything that was read & cached * from the file. * * This method calls the <code>loadFile()</code> method if * any of: * file has a new modify time since the last check * file used to exist and now does not * file used to not exist but now does * @return Returns true if the file was reloaded. */ bool checkAndReload(); std::string filename() const; /** * @brief Add this live file to an automated recheck. * * Normally, just calling checkAndReload() is enough. In some * cases though, you may need to let the live file periodically * check itself. */ void addToEventTimer(); void setRefreshPeriod(F32 seconds); protected: /** * @breif Implement this to load your file if it changed. * * This method is called automatically by <code>checkAndReload()</code>, * so though you must implement this in derived classes, you do * not need to call it manually. * @return Returns true if the file was successfully loaded. */ virtual bool loadFile() = 0; /** * @brief Implement this method if you want to get a change callback. * * This virtual function will be called automatically at the end * of <code>checkAndReload()</code> if a new configuration was * loaded. This does not track differences between the current and * newly loaded file, so any successful load event will trigger a * <code>changed()</code> callback. Default is to do nothing. */ virtual void changed() {} private: class Impl; Impl& impl; }; #endif //LL_LLLIVEFILE_H