--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/common/logger.h	Mon Feb 08 16:43:14 2016 +0100
@@ -0,0 +1,217 @@
+/*
+ * logger.h -- irccd logging
+ *
+ * Copyright (c) 2013-2016 David Demelier <markand@malikania.fr>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef _IRCCD_LOGGER_H_
+#define _IRCCD_LOGGER_H_
+
+#include <irccd-config.h>
+
+#include <memory>
+#include <sstream>
+#include <utility>
+
+namespace irccd {
+
+namespace log {
+
+/**
+ * @enum Level
+ * @brief Which level of warning
+ */
+enum class Level {
+	Info,			//!< Standard information (disabled if verbose is false)
+	Warning,		//!< Warning (always shown)
+	Debug			//!< Debug message (only if compiled in debug mode)
+};
+
+/* --------------------------------------------------------
+ * Interface -- abstract logging interface
+ * -------------------------------------------------------- */
+
+/**
+ * @class Interface
+ * @brief Interface to implement new logger mechanisms
+ *
+ * Derive from this class and use Logger::setInterface() to change logging
+ * system.
+ *
+ * @see File
+ * @see Console
+ * @see Syslog
+ * @see Silent
+ */
+class Interface {
+public:
+	/**
+	 * Write the line to the logs. The line to write will never contains
+	 * trailing new line character.
+	 *
+	 * @param level the level
+	 * @param line the line without trailing \n
+	 */	
+	virtual void write(Level level, const std::string &line) noexcept = 0;
+};
+
+/* --------------------------------------------------------
+ * Console -- logs to console
+ * -------------------------------------------------------- */
+
+/**
+ * @class Console
+ * @brief Logger implementation for console output
+ */
+class Console : public Interface {
+public:
+	/**
+	 * @copydoc Interface::write
+	 */
+	void write(Level level, const std::string &line) noexcept override;
+};
+
+/* --------------------------------------------------------
+ * File -- logs to a file
+ * -------------------------------------------------------- */
+
+/**
+ * @class File
+ * @brief Output to a file
+ */
+class File : public Interface {
+private:
+	std::string m_outputNormal;
+	std::string m_outputError;
+
+public:
+	/**
+	 * Outputs to files. Info and Debug are written in normal and Warnings
+	 * in errors.
+	 *
+	 * The same path can be used for all levels.
+	 *
+	 * @param normal the path to the normal logs
+	 * @param errors the path to the errors logs
+	 */
+	File(std::string normal, std::string errors);
+
+	/**
+	 * @copydoc Interface::write
+	 */
+	void write(Level level, const std::string &line) noexcept override;
+};
+
+/* --------------------------------------------------------
+ * Silent -- disable all logs
+ * -------------------------------------------------------- */
+
+/**
+ * @class Silent
+ * @brief Use to disable logs
+ *
+ * Useful for unit tests when some classes may emits log.
+ */
+class Silent : public Interface {
+public:
+	/**
+	 * @copydoc Interface::write
+	 */
+	void write(Level level, const std::string &line) noexcept override;
+};
+
+/* --------------------------------------------------------
+ * Syslog -- system logger
+ * -------------------------------------------------------- */
+
+#if defined(HAVE_SYSLOG)
+
+/**
+ * @class Syslog
+ * @brief Implements logger into syslog
+ */
+class Syslog : public Interface {
+public:
+	/**
+	 * Open the syslog.
+	 */
+	Syslog();
+
+	/**
+	 * Close the syslog.
+	 */
+	~Syslog();
+
+	/**
+	 * @copydoc Interface::write
+	 */
+	void write(Level level, const std::string &line) noexcept override;
+};
+
+#endif // !HAVE_SYSLOG
+
+/* --------------------------------------------------------
+ * Functions
+ * -------------------------------------------------------- */
+
+/**
+ * Update the logger interface.
+ *
+ * @param iface the new interface
+ */
+void setInterface(std::unique_ptr<Interface> iface) noexcept;
+
+/**
+ * Get the stream for informational messages.
+ *
+ * @return the stream
+ * @note Has no effect if verbose is set to false.
+ */
+std::ostream &info() noexcept;
+
+/**
+ * Get the stream for warnings.
+ *
+ * @return the stream
+ */
+std::ostream &warning() noexcept;
+
+/**
+ * Get the stream for debug messages.
+ *
+ * @return the stream
+ * @note Has no effect if compiled in release mode.
+ */
+std::ostream &debug() noexcept;
+
+/**
+ * Tells if verbose is enabled.
+ *
+ * @return true if enabled
+ */
+bool isVerbose() noexcept;
+
+/**
+ * Set the verbosity mode.
+ *
+ * @param mode the new mode
+ */
+void setVerbose(bool mode) noexcept;
+
+} // !log
+
+} // !irccd
+
+#endif // !_IRCCD_LOGGER_H_