/*-*-c++-*- * $Id$ * * This file is part of plptools. * * Copyright (C) 1999 Philip Proudman * Copyright (C) 1999-2001 Fritz Elfert * * This program 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; either version 2 of the License, or * (at your option) any later version. * * 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, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #ifndef _LOG_H_ #define _LOG_H_ #include #include /** * A streambuffer, logging via syslog * * logbuf can be used, if you want to use syslog for * logging but don't want to change all your nice * C++-style output statements in your code. * * Here is an example showing the usage of logbuf: * *
 *	openlog("myDaemon", LOG_CONS|LOG_PID, LOG_DAEMON);
 *	logbuf ebuf(LOG_ERR, 2);
 *	ostream lerr(&ebuf);
 *
 *	... some code ...
 *
 *	lerr << "Whoops, got an error" << endl;
 * 
* * The second optional argument of the constructor can be used * to switch the output destination between syslog and some * file. If it is omitted or set to -1, logging can be switched on * or off. The initial state is on. */ class logbuf : public std::streambuf { public: /** * Constructs a new instance. * * @param loglevel The log level for this instance. * see syslog(3) for symbolic names to use. * @param fd An optional file descriptor to use * if switched off. */ logbuf(int loglevel, int fd = -1); /** * Switches loggin on or off. * * @param newstate The desired state. */ void setOn(bool newstate) { _on = newstate; } /** * Modifies the loglevel of this instance. * * @param newlevel The new loglevel. */ void setLevel(int newlevel) { _level = newlevel; } /** * Retrieve the current state. * * @returns The current state. */ bool on() { return _on; } /** * Retrieves the current loglevel. * * @returns The current loglevel. */ int level() { return _level; } /** * Called by the associated * ostream to write a character. * Stores the character in a buffer * and calls syslog(level, buffer) * whenever a LF is seen. */ int overflow(int c = EOF); private: /** * Pointer to next char in buffer. */ char *ptr; /** * Current length of buffer. */ unsigned int len; /** * The log level to use with syslog. */ int _level; /** * File descriptor to use when switched off. * If this is -1, don't output anything. */ int _fd; /** * Log flag. */ bool _on; /** * The internal buffer for holding * messages. */ char buf[1024]; }; #endif /* * Local variables: * c-basic-offset: 4 * End: */