Line data    Source code

       1             : /*
       2             :  * File:
       3             :  *    advgetopt/log.h -- a replacement to the Unix getopt() implementation
       4             :  *
       5             :  * License:
       6             :  *    Copyright (c) 2006-2019  Made to Order Software Corp.  All Rights Reserved
       7             :  *
       8             :  *    https://snapwebsites.org/
       9             :  *    contact@m2osw.com
      10             :  *
      11             :  *    This program is free software; you can redistribute it and/or modify
      12             :  *    it under the terms of the GNU General Public License as published by
      13             :  *    the Free Software Foundation; either version 2 of the License, or
      14             :  *    (at your option) any later version.
      15             :  *
      16             :  *    This program is distributed in the hope that it will be useful,
      17             :  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
      18             :  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      19             :  *    GNU General Public License for more details.
      20             :  *
      21             :  *    You should have received a copy of the GNU General Public License along
      22             :  *    with this program; if not, write to the Free Software Foundation, Inc.,
      23             :  *    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
      24             :  *
      25             :  * Authors:
      26             :  *    Alexis Wilke   alexis@m2osw.com
      27             :  *    Doug Barbieri  doug@m2osw.com
      28             :  */
      29             : #pragma once
      30             : 
      31             : /** \file
      32             :  * \brief Declaration of the log class used to send error messages.
      33             :  *
      34             :  * The library offers a log facility for when messages are generated on
      35             :  * errors and various output (i.e. --help).
      36             :  */
      37             : 
      38             : // C++ lib
      39             : //
      40             : #include    <iostream>
      41             : #include    <sstream>
      42             : 
      43             : 
      44             : namespace advgetopt
      45             : {
      46             : 
      47             : 
      48             : enum class log_level_t
      49             : {
      50             :     debug,
      51             :     info,
      52             :     warning,
      53             :     error,
      54             :     fatal
      55             : };
      56             : 
      57             : std::string to_string(log_level_t level);
      58             : 
      59             : 
      60             : typedef void (*log_callback)(log_level_t, std::string const & message);
      61             : 
      62             : void set_log_callback(log_callback callback);
      63             : 
      64             : 
      65           4 : class logger
      66             : {
      67             : public:
      68             :     template<typename T>
      69        1253 :     logger & operator << (T const & v)
      70             :     {
      71        1253 :         f_log << v;
      72        1253 :         return *this;
      73             :     }
      74             : 
      75         221 :     logger & operator << (log_level_t const & level)
      76             :     {
      77         221 :         f_level = level;
      78         221 :         return *this;
      79             :     }
      80             : 
      81         221 :     logger & operator << (logger & (*func)(logger &))
      82             :     {
      83         221 :         func(*this);
      84         221 :         return *this;
      85             :     }
      86             : 
      87             :     logger &            end();
      88             : 
      89             : private:
      90             :     log_level_t         f_level = log_level_t::error;
      91             :     std::stringstream   f_log = std::stringstream();
      92             : };
      93             : 
      94             : 
      95         221 : inline logger & end(logger & l) { return l.end(); }
      96             : 
      97             : 
      98             : extern logger   log;
      99             : 
     100             : 
     101             : }   // namespace advgetopt
     102             : // vim: ts=4 sw=4 et