From: g0dil Date: Tue, 20 Feb 2007 11:19:40 +0000 (+0000) Subject: Logger API skeleton implementation X-Git-Url: http://g0dil.de/git?a=commitdiff_plain;h=f53813669f2da13d0365950b5087cfe1d3cc829b;p=senf.git Logger API skeleton implementation git-svn-id: https://svn.berlios.de/svnroot/repos/senf/trunk@204 270642c3-0616-0410-b53a-bc976706d245 --- diff --git a/Utils/Logger.hh b/Utils/Logger.hh new file mode 100644 index 0000000..3082632 --- /dev/null +++ b/Utils/Logger.hh @@ -0,0 +1,218 @@ +// Copyright (C) 2007 +// Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS) +// Kompetenzzentrum fuer Satelitenkommunikation (SatCom) +// Stefan Bund +// +// 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. + +/** \file + \brief Logger public header */ + +/** \defgroup logger The SENF Logger + + The Loggger infrastructure shall implement a highliy flexible compile- and run-time configurable + logging infrastructure supporting multiple streams, user defineable log areas and fine grained + log levels. Logging can be configured at compile and runtime on any combination of above + parameters. The library supports a host of log targets and messages can be routed into multiple + targets at the same time. To allow concise usage of the libarary, a utlity to define logging + defaults for any scope is provided. + + An important basic concept of the library is, that most of the macros take a variable number of + arguments. Since this is not supported in the needed manner by the C++ preprocessor, the + arguments are encoded into a Boost.Preprocessor like + sequence: + + \code + SENF_LOG( (senf::log::Debug)(senf::log::NOTICE)(FroblizerArea)("The log message") ); + \endcode + + The last sequence element always is the log message. Before that we have a number of log + parameters in arbitrary order. Since giving all the parameters in every log message is + to verbose, there are two helpful constructs to reduce the verbosity. Using \ref SENF_LOG_DEFAULTS it + is possible to define the default logging parameters to be used within a given scope. Using + \ref SENF_LOG_DEF_ALIAS you can define an alias (which is a scoped symbol) as an arbitrary + combination of parameters. + + \code + SENF_LOG_DEF_STREAM(userLog); + + class Froblizer + { + // Define a new log area + SENF_LOG_DEF_AREA(FroblizerArea); + + // Set default log parameters for this scope + SENF_LOG_DEFAULTS( (senf::log::Debug) (senf::log::NOTICE) (FroblizerArea) ); + + // Define an alias for emergency messages to the sysadmin. + // The log area is inherited from the default at the place, where this + // alias is used *not* where it is defined + SENF_LOG_DEF_ALIAS(LogEmerg, (userLog) (senf::log::CRITICAL)); + + void test(); + + public: + void froblize(); + }; + + void Froblizer::froblize() + { + SENF_LOG(("This is the Debug stream at level NOTICE in the FroblizeArea")); + SENF_LOG((senf::log::WARNING) ("Same stream and area but at warning level")); + SENF_LOG((LogEmerg) ("This goes to the userLog at level CRITICAL in the FroblizerArea")); + } + + void Froblizer::test() + { + // Change the default log level for this method. stream and area are taken + // from the next scope up + SENF_LOG_DEFAULTS((senf::log::DEBUG)); + + SENF_LOG(("Log to Debug stream in Froblizer area however at DEBUG level")); + } + \endcode + + Currently, the library is not implemented in any way. The interface has been defined up to a + point and we have dummy implementations of the 'in-code' part ot the interface. This is the + part, which is called throughout the code. The configuration API is defined but we don't even + have a template implementation. However, this allows starting to use the SENF Logger in newly + developed code. Even though this code will unconditionally log everything to \c std::cerr for + now and errors in the parameter specification will not be caught (since they are just ignored) + the logging should work automatically as advertised as soon as the logger is completely + implemented. + + \implementation I would have much preferred a more C++ like implementation. However given the + design goals + \li Flexible configuration at compile and runtime + \li Concise usage and simple interface + \li Zero overhead for compile-time disabled log messages + + I did not find any implementation which was not either completely convoluted, unusable or + slow. So I turned to a macro based implementation which can provide all the design goals stated + above. + */ + +#ifndef HH_Logger_ +#define HH_Logger_ 1 + +// Custom includes +#include +#include +#include +#include + +//#include "Logger.mpp" +///////////////////////////////hh.p//////////////////////////////////////// + +namespace senf { + +# ifndef _senf_LOG_STREAM +# define _senf_LOG_STREAM std::cerr +# endif + + /// \addtogroup logger + /// @{ + + /** \brief Write log message + + This macro will write it's last argument to the log stream. The last argument must be an + expression which will be placed after a streaming \c operator<< (like + some-log-sttream \c << last-macro-arg). + \code + BOOST_LOG((parameters...)("log message " << args << ...)); + \endcode + + \hideinitializer + */ +# define SENF_LOG(args) \ + _senf_LOG_STREAM << BOOST_PP_SEQ_ELEM(BOOST_PP_DEC(BOOST_PP_SEQ_SIZE(args)),args) \ + << std::endl; + + /** \brief Enable block based on logging parameters + + This macro is like SENF_LOG, however instead of writing a simple message, this macro allows + to specify a complete block of code to be executed if the log message is enabled. + \code + BOOST_LOG_BLOCK((parameters...)({ + // arbitrary code using 'log' for logging + log << "log message"; + })); + \endcode + + \hideinitializer + */ +# define SENF_LOG_BLOCK(args) \ + do { \ + std::ostream & log (_senf_LOG_STREAM); \ + BOOST_PP_SEQ_ELEM(BOOST_PP_DEC(BOOST_PP_SEQ_SIZE(args)),args) \ + log << std::endl; \ + } while (0) + + /** \brief Set scope default log parameters + + Sets the default log parameters for the current scope + \code + BOOST_LOG_DEFAULTS((parameters...)); + \endcode + + \hideinitializer + */ +# define SENF_LOG_DEFAULTS(args) + + /** \brief Define log area + + Defines a new log area named \a area. The area is defined as a symbol in the current scope. + + \hideinitializer + */ +# define SENF_LOG_DEF_AREA(area) + + /** \brief Define log stream + + Defines a new log stream named \a stream. The stream is defined as a symbol in the current + scope. + + \hideinitializer + */ +# define SENF_LOG_DEF_STREAM(stream) + + /** \brief Define log parameter alias + + Defines a new parameter alias named \a alias as an alias for the parameters in \a args. The + alias is defined as a symbol in the current scope. + + \hideinitializer + */ +# define SENF_LOG_DEF_ALIAS(alias,args) + + /// @} + +} + +///////////////////////////////hh.e//////////////////////////////////////// +//#include "Logger.cci" +//#include "Logger.ct" +//#include "Logger.cti" +#endif + + +// Local Variables: +// mode: c++ +// fill-column: 100 +// c-file-style: "senf" +// ispell-local-dictionary: "american" +// End: diff --git a/Utils/Logger.test.cc b/Utils/Logger.test.cc new file mode 100644 index 0000000..3efa3d5 --- /dev/null +++ b/Utils/Logger.test.cc @@ -0,0 +1,68 @@ +// Copyright (C) 2007 +// Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS) +// Kompetenzzentrum fuer Satelitenkommunikation (SatCom) +// Stefan Bund +// +// 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. + +/** \file + \brief Logger.test unit tests */ + +//#include "Logger.test.hh" +//#include "Logger.test.ih" + +// Custom includes +#include +#define _senf_LOG_STREAM logstream +#include "Logger.hh" + +#include +#include + +#define prefix_ +///////////////////////////////cc.p//////////////////////////////////////// + +BOOST_AUTO_UNIT_TEST(logger) +{ + std::stringstream logstream; + + SENF_LOG_DEFAULTS( (senf::log::Debug) (senf::log::NOTICE) ); + SENF_LOG_DEF_ALIAS( LogFoo, (senf::log::Debug) (senf::log::CRITICAL) ); + SENF_LOG_DEF_STREAM( myStream ); + SENF_LOG_DEF_AREA( myArea ); + + SENF_LOG(("Log message")); + + SENF_LOG((LogFoo) ("Another log message: " << 10)); + + SENF_LOG_BLOCK((senf::log::Debug) (senf::log::WARNING) ({ + log << "Last message"; + log << " continued here"; + })); + + BOOST_CHECK_EQUAL( logstream.str(), "Log message\nAnother log message: 10\nLast message continued here\n" ); +} + +///////////////////////////////cc.e//////////////////////////////////////// +#undef prefix_ + + +// Local Variables: +// mode: c++ +// fill-column: 100 +// c-file-style: "senf" +// ispell-local-dictionary: "american" +// End: