4 // Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS)
5 // Kompetenzzentrum fuer Satelitenkommunikation (SatCom)
6 // Stefan Bund <g0dil@berlios.de>
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 2 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the
20 // Free Software Foundation, Inc.,
21 // 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 \brief Log public header */
30 #include <boost/preprocessor/seq/size.hpp>
31 #include <boost/preprocessor/dec.hpp>
32 #include <boost/preprocessor/seq/elem.hpp>
33 #include <boost/preprocessor/seq/pop_back.hpp>
34 #include "Parameters.hh"
38 ///////////////////////////////hh.p////////////////////////////////////////
40 /** \defgroup logging Logging commands
42 The logging library provides several commands to create log messages. All these macro commands
43 take a variable number of arguments. Since this is not supported in a usable way by the C++
44 preprocessor, the arguments are encoded into a <a
45 href="http://www.boost.org/libs/preprocessor/doc/index.html">Boost.Preprocessor</a> like
49 SENF_LOG( (senf::log::Debug)(senf::log::NOTICE)(FroblizerArea)("The log message") );
52 The argument is comprised of a sequence of parameters and the log message itself. The parameters
54 \li The <em>log stream</em>,
55 \li the <em>log area</em>,
56 \li the <em>log level</em>,
58 These parameters are optional and may be specified <i>in arbitrary order</i> (with the log
59 message always being the last sequence element) and even multiple times in the parameter
60 sequence. If some argument type occurs multiple times, the last occurrence wins. If any one of
61 the parameters is not specified, it's current default value will be used.
63 This current default value is set using \ref SENF_LOG_DEFAULT_STREAM, \ref SENF_LOG_DEFAULT_AREA
64 and \ref SENF_LOG_DEFAULT_LEVEL respectively. These macros set the default stream, area and/or
65 level of the current scope. The logging library defines the global defaults for these values to
66 be \c senf::log::Debug (\e stream), senf::log::DefaultArea (\e area), and senf::log::NONE (\e
69 The log level senf::log::NONE is special. If the log level is set to this value, the log level
70 will be set from the stream provided default value.
72 All these parameters must be <em>compile time constants</em> (they are all types, so it's
73 difficult form them to be something else).
79 ///\name Generating log messages
82 /** \brief Write log message
84 This macro will write it's last argument to the log stream. The last argument must be an
85 expression which will be placed after a streaming \c operator<< (like
86 <i>some-log-stream</i> \c << <i>last-macro-arg</i>).
88 SENF_LOG((parameters...)("log message " << args << ...));
93 #define SENF_LOG(args) \
94 SENF_LOG_BLOCK_( SENF_LOG_MERGE_PARAMETERS(BOOST_PP_SEQ_POP_BACK(args)), \
95 { log << BOOST_PP_SEQ_ELEM(BOOST_PP_DEC(BOOST_PP_SEQ_SIZE(args)),args); })
97 /** \brief Write log message (template context)
99 This macro is used like \ref SENF_LOG() if called from a template context
103 #define SENF_LOG_TPL(args) \
104 SENF_LOG_BLOCK_( SENF_LOG_MERGE_PARAMETERS_TPL(BOOST_PP_SEQ_POP_BACK(args)), \
105 { log << BOOST_PP_SEQ_ELEM(BOOST_PP_DEC(BOOST_PP_SEQ_SIZE(args)),args); })
107 /** \brief Enable block based on logging parameters
109 This macro is like SENF_LOG, however instead of writing a simple message, this macro allows
110 to specify a complete block of code to be executed if the log message is enabled.
112 SENF_LOG_BLOCK((parameters...)({
113 // arbitrary code using 'log' for logging
114 log << "log message";
120 #define SENF_LOG_BLOCK(args) \
121 SENF_LOG_BLOCK_( SENF_LOG_MERGE_PARAMETERS(BOOST_PP_SEQ_POP_BACK(args)), \
122 BOOST_PP_SEQ_ELEM(BOOST_PP_DEC(BOOST_PP_SEQ_SIZE(args)),args))
124 /** \brief Write log message (template context)
126 This macro is used like \ref SENF_LOG_BLOCK() if called from a template context
130 #define SENF_LOG_BLOCK_TPL(args) \
131 SENF_LOG_BLOCK_TPL_( SENF_LOG_MERGE_PARAMETERS_TPL(BOOST_PP_SEQ_POP_BACK(args)), \
132 BOOST_PP_SEQ_ELEM(BOOST_PP_DEC(BOOST_PP_SEQ_SIZE(args)),args))
137 ///////////////////////////////hh.e////////////////////////////////////////
147 // comment-column: 40
148 // c-file-style: "senf"
149 // indent-tabs-mode: nil
150 // ispell-local-dictionary: "american"
151 // compile-command: "scons -u test"