// $Id$
//
-// Copyright (C) 2007
-// Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS)
-// Kompetenzzentrum fuer Satelitenkommunikation (SatCom)
+// Copyright (C) 2007
+// Fraunhofer Institute for Open Communication Systems (FOKUS)
+// Competence Center NETwork research (NET), St. Augustin, GERMANY
// Stefan Bund <g0dil@berlios.de>
//
// This program is free software; you can redistribute it and/or modify
\section logging_concepts Concepts
- The log messages are devided along several categories: \e streams, \e areas and log \e levels.
+ Log messages are arbitrarily created throughout the code using simple log statements (which are
+ macros). Besides the log message itself, every log message is labeled with additional
+ information: The \e stream, the \e area and a log \e level. If the message is not compile-time
+ disabled, the message is then directed to one or several log \e targets.
- A \e stream combines log messages with a single purpose. There is one default stream, called \c
- senf::log::Debug. New streams are defined with \ref SENF_LOG_DEF_STREAM.
+ A \e stream combines log messages with a single purpose: Debug messages, access logging and so
+ on. Any number of streams may be defined. There is one predefined default stream called \c
+ senf::log::Debug. (see: \ref SENF_LOG_DEF_STREAM)
- An \e area labels a log message with the source location of the message. An area is an arbitrary
- tag which may be added to the message. There is one default area called \c
- senf::log::DefaultArea. New areas are defined either with \ref SENF_LOG_DEF_AREA or \ref
- SENF_LOG_CLASS_AREA, the latter being the more typical. The area will normally indicate the
- class or subsystem from which the message was generated.
+ The \e area gives information about the source location of the message. Areas may be defined and
+ assigned arbitrarily but should be used to label messages from a single class or subsystem. It
+ is possible to reuse a class as it's own area tag, which is often desireable. There is a
+ default area \c senf::log::DefaultArea which is used, when no other area is assigned. (see: \ref
+ SENF_LOG_DEF_AREA, \ref SENF_LOG_CLASS_AREA)
- The log \e level gives information on the importance of the message. The list lof \ref loglevels
- is fixed.
+ The log \e level gives information on the importance of the message. The list of log-levels is
+ fixed. (see: \ref loglevels)
- After log messages have been created, they have to be placed somewhere. This is the
- responsibility of the \e target. A target is an arbitrary sink for log messages. The target
- manages message routing and will pass the message on to it's destination, be it the system
- console, some log file or some other place (e.g. an SQL database). The target is responsible for
- formating the message.
+ Depending on their the \e stream, \e area and \e level information, log messages can be enabled
+ or disabled at \e compile time. Messages disabled at compile time should not generate any
+ code. (see: \ref SENF_LOG_CONF)
+
+ To be of any use, the log messages have to be written somewhere. This is the responsibility of
+ any number of \e targets. A \e target receives messages and using it's routing information
+ decides, wether the message is output or not. A message may be routed to multiple targets
+ simultaneously or may not be output by any target at all. (see: \ref targets)
\section logging_tutorial Tutorial introduction
SENF_LOG(("Log to UserLog stream in Froblizer area however at VERBOSE level"));
}
+
+ int main(int, char **)
+ {
+ // Set up the routing targets
+ senf::log::ConsoleTarget & console (senf::log::ConsoleTarget::instance());
+ senf::log::FileTarget logfile ("my.log");
+
+ // Debug messages go to the console
+ console.route<senf::log::Debug>();
+ // Important user message are written to the log file
+ logfile.route<foo::UserLog, senf::log::IMPORTANT>();
+ }
\endcode
\implementation I would have much preferred a more C++ like implementation. However given the
projects / senf.git / blobdiff