src/Logger.h

   1 /*
   2  * This file is part of the vng project
   3  * Copyright (C) 2008 Thomas Zander <tzander@trolltech.com>
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #ifndef Logger_H
  20 #define Logger_H
  21
  22 #include <QTextStream>
  23
  24 class LoggerPrivate;
  25
  26 /**
  27  * Logs any sort of information at configurable log levels.
  28  */
  29 class Logger
  30 {
  31 public:
  32     enum Verbosity {
  33         Quiet,
  34         Chatty,
  35         Verbose,
  36         Debug
  37     };
  38
  39     Logger();
  40
  41     /// return an outputstream logger irregardless of the loglevel
  42     static QTextStream &standardOut();
  43     /// return an outputstream or a dummy logger based on verbosity set on the logger and passed as argument.
  44     static QTextStream &log(Verbosity verbosity);
  45     /// equals log(Debug)
  46     static QTextStream &debug();
  47     /// equals log(Chatty)
  48     static QTextStream &info();
  49     /// equals log(Verbose)
  50     static QTextStream &warn();
  51     /// equals log(Quiet)
  52     static QTextStream &error();
  53     /**
  54      * in case a pager is used calling this will explicitly flush the output to the screen.
  55      * You should not have to call this because the different Logger methods which return a QTextStream call it automatically.
  56      */
  57     static void flushPager();
  58
  59     /**
  60      * by calling this method all the logger operations will be routed via a pager like less (if available).
  61      * @see stopPager()
  62      */
  63     static void startPager();
  64     /**
  65      * by calling this method all the logger operations will be routed via a pager like less (if available).
  66      * @see stopPager()
  67      */
  68     static void stopPager();
  69     /// return true when there is a pager in use that doesn't support throughput of color information.
  70     static bool hasNonColorPager();
  71     /// Set the verbosity of the logger.  Already in use logger streams will not be affected.
  72     static void setVerbosity(Verbosity verbosity);
  73     /// return the verbosity set on the logger.
  74     static Verbosity verbosity();
  75
  76 private:
  77     LoggerPrivate * const d;
  78 };
  79
  80 #endif