paludis  Version 2.6.0
log.hh
Go to the documentation of this file.
1 /* vim: set sw=4 sts=4 et foldmethod=syntax : */
2 
3 /*
4  * Copyright (c) 2006, 2007, 2008, 2009, 2010, 2011 Ciaran McCreesh
5  *
6  * This file is part of the Paludis package manager. Paludis is free software;
7  * you can redistribute it and/or modify it under the terms of the GNU General
8  * Public License version 2, as published by the Free Software Foundation.
9  *
10  * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
11  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
12  * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
13  * details.
14  *
15  * You should have received a copy of the GNU General Public License along with
16  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
17  * Place, Suite 330, Boston, MA 02111-1307 USA
18  */
19 
20 #ifndef PALUDIS_GUARD_PALUDIS_LOG_HH
21 #define PALUDIS_GUARD_PALUDIS_LOG_HH 1
22 
25 #include <paludis/util/pimp.hh>
26 #include <iosfwd>
27 #include <string>
28 
29 /** \file
30  * Declarations for Log and related classes.
31  *
32  * \ingroup g_log
33  *
34  * \section Examples
35  *
36  * - None at this time.
37  */
38 
39 namespace paludis
40 {
41 #include <paludis/util/log-se.hh>
42 
44 
45  /**
46  * Singleton class that handles log messages.
47  *
48  * \ingroup g_log
49  */
51  public Singleton<Log>
52  {
53  friend class Singleton<Log>;
54  friend class LogMessageHandler;
55 
56  private:
57  Pimp<Log> _imp;
58 
59  Log();
60 
61  void _message(const std::string & id, const LogLevel, const LogContext, const std::string &);
62 
63  public:
64  /**
65  * Destructor, to be called only by our InstantiationPolicy.
66  */
67  ~Log();
68 
69  /**
70  * Only display messages of at least this level.
71  */
72  void set_log_level(const LogLevel);
73 
74  /**
75  * Fetch the current log level.
76  */
77  LogLevel log_level() const
78  PALUDIS_ATTRIBUTE((warn_unused_result));
79 
80  /**
81  * Log a message.
82  *
83  * The return value can be appended to using
84  * LogMessageHandler::operator<<(). When the return value is
85  * destroyed (that is to say, at the end of the statement), the log
86  * message is written.
87  */
88  LogMessageHandler message(const std::string & id,
89  const LogLevel, const LogContext) PALUDIS_ATTRIBUTE((warn_unused_result));
90 
91  /**
92  * Change the log stream.
93  */
94  void set_log_stream(std::ostream * const);
95 
96  /**
97  * Set our program name.
98  */
99  void set_program_name(const std::string &);
100  };
101 
102  /**
103  * Used by Log::message().
104  *
105  * \see Log
106  * \ingroup g_log
107  */
109  {
110  friend LogMessageHandler Log::message(const std::string &, const LogLevel, const LogContext);
111 
112  private:
113  Log * _log;
114  std::string _id;
115  std::string _message;
116  LogLevel _log_level;
117  LogContext _log_context;
118 
120  LogMessageHandler(Log * const, const std::string &, const LogLevel, const LogContext);
121  void operator= (const LogMessageHandler &);
122 
123  void _append(const std::string & s);
124 
125  public:
126  ///\name Basic operations
127  ///\{
128 
130 
131  ///\}
132 
133  /**
134  * Append some text to our message.
135  */
136  template <typename T_>
138  operator<< (const T_ & t)
139  {
140  _append(stringify(t));
141  return *this;
142  }
143  };
144 
145  extern template class Pimp<Log>;
146 }
147 
148 #endif
Definition: pimp.hh:51
Definition: about_metadata-fwd.hh:23
LogMessageHandler message(const std::string &id, const LogLevel, const LogContext) PALUDIS_ATTRIBUTE((warn_unused_result))
LogContext
Definition: log.hh:39
std::ostream & operator<<(std::ostream &, const WantPhase &) PALUDIS_VISIBLE
Definition: log.hh:50
LogLevel
Definition: log.hh:13
Definition: singleton.hh:44
std::string stringify(const T_ &item)
Definition: stringify.hh:166
Definition: log.hh:108
#define PALUDIS_ATTRIBUTE(x)
Definition: attributes.hh:53
#define PALUDIS_VISIBLE
Definition: attributes.hh:59