RetroShare/retroshare-gui/src/util/log.h
2018-12-27 14:39:10 +01:00

163 lines
6.9 KiB
C++

/*******************************************************************************
* util/log.h *
* *
* Copyright (c) 2006-2007, crypton <retroshare.project@gmail.com> *
* Copyright (c) 2006, Matt Edman, Justin Hipple *
* *
* This program is free software: you can redistribute it and/or modify *
* it under the terms of the GNU Affero General Public License as *
* published by the Free Software Foundation, either version 3 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 Affero General Public License for more details. *
* *
* You should have received a copy of the GNU Affero General Public License *
* along with this program. If not, see <https://www.gnu.org/licenses/>. *
* *
*******************************************************************************/
#ifndef _LOG_H
#define _LOG_H
#include <QObject>
#include <QFile>
#include <QStringList>
#include <QIODevice>
#include <QHostAddress>
/** The Log class is similar to the QDebug class provided with Qt, but with
* finer-grained logging levels, slightly different output (for example, not
* everything is wrapped in double quotes), supports using .arg(), and can
* still be used even if Qt was compiled with QT_NO_DEBUG_STREAM. */
class Log
{
public:
/** Logging severity levels. */
enum LogLevel {
Debug = 0, /**< Verbose debugging output. */
Info, /**< Primarily program flow output. */
Notice, /**< Non-failure (but important) events. */
Warn, /**< Recoverable failure conditions. */
Error, /**< Critical, non-recoverable errors. */
Off, /**< No logging output. */
Unknown /**< Unknown/invalid log level. */
};
class LogMessage;
/** Default constructor. */
Log();
/** Destructor. */
~Log();
/** Opens a file on disk (or stdout or stderr) to which log messages will be
* written. */
bool open(FILE *file);
/** Opens a file on disk to which log messages will be written. */
bool open(QString file);
/** Closes the log file. */
void close();
/** Returns true if the log file is open and ready for writing. */
bool isOpen() { return _logFile.isOpen() && _logFile.isWritable(); }
/** Returns a string description of the last file error encountered. */
QString errorString() { return _logFile.errorString(); }
/** Sets the current log level to <b>level</b>. */
void setLogLevel(LogLevel level);
/** Returns a list of strings representing valid log levels. */
static QStringList logLevels();
/** Returns a string description of the given LogLevel <b>level</b>. */
static inline QString logLevelToString(LogLevel level);
/** Returns a LogLevel for the level given by <b>str</b>. */
static LogLevel stringToLogLevel(QString str);
/** Creates a log message with severity <b>level</b> and initial message
* contents <b>message</b>. The log message can be appended to until the
* returned LogMessage's destructor is called, at which point the complete
* message is written to the log file. */
LogMessage log(LogLevel level, QString message);
/** Creates a log message with severity <b>level</b>. The log message can be
* appended to until the returned LogMessage's destructor is called, at
* which point the complete message is written to the log file. */
inline LogMessage log(LogLevel level);
private:
LogLevel _logLevel; /**< Minimum log severity level. */
QFile _logFile; /**< Log output destination. */
};
/** This internal class represents a single message that is to be written to
* the log destination. The message is buffered until it is written to the
* log in this class's destructor. */
class Log::LogMessage
{
public:
struct Stream {
Stream(Log::LogLevel t, QIODevice *o)
: type(t), out(o), ref(1) {}
Log::LogLevel type;
QIODevice *out;
int ref;
QString buf;
} *stream;
inline LogMessage(Log::LogLevel t, QIODevice *o)
: stream(new Stream(t,o)) {}
inline LogMessage(const LogMessage &o)
: stream(o.stream) { ++stream->ref; }
inline QString toString() const;
~LogMessage();
/* Support both the << and .arg() methods */
inline LogMessage &operator<<(const QString &t)
{ stream->buf += t; return *this; }
inline LogMessage arg(const QString &a)
{ stream->buf = stream->buf.arg(a); return *this; }
inline LogMessage &operator<<(const QStringList &a)
{ stream->buf += a.join(","); return *this; }
inline LogMessage arg(const QStringList &a)
{ stream->buf = stream->buf.arg(a.join(",")); return *this; }
inline LogMessage &operator<<(const QHostAddress &a)
{ stream->buf += a.toString(); return *this; }
inline LogMessage arg(const QHostAddress &a)
{ stream->buf = stream->buf.arg(a.toString()); return *this; }
inline LogMessage &operator<<(short a)
{ stream->buf += QString::number(a); return *this; }
inline LogMessage arg(short a)
{ stream->buf = stream->buf.arg(a); return *this; }
inline LogMessage &operator<<(ushort a)
{ stream->buf += QString::number(a); return *this; }
inline LogMessage arg(ushort a)
{ stream->buf = stream->buf.arg(a); return *this; }
inline LogMessage &operator<<(int a)
{ stream->buf += QString::number(a); return *this; }
inline LogMessage arg(int a)
{ stream->buf = stream->buf.arg(a); return *this; }
inline LogMessage &operator<<(uint a)
{ stream->buf += QString::number(a); return *this; }
inline LogMessage arg(uint a)
{ stream->buf = stream->buf.arg(a); return *this; }
inline LogMessage &operator<<(long a)
{ stream->buf += QString::number(a); return *this; }
inline LogMessage arg(long a)
{ stream->buf = stream->buf.arg(a); return *this; }
inline LogMessage &operator<<(ulong a)
{ stream->buf += QString::number(a); return *this; }
inline LogMessage arg(ulong a)
{ stream->buf = stream->buf.arg(a); return *this; }
inline LogMessage &operator<<(qlonglong a)
{ stream->buf += QString::number(a); return *this; }
inline LogMessage arg(qlonglong a)
{ stream->buf = stream->buf.arg(a); return *this; }
inline LogMessage &operator<<(qulonglong a)
{ stream->buf += QString::number(a); return *this; }
inline LogMessage arg(qulonglong a)
{ stream->buf = stream->buf.arg(a); return *this; }
};
#endif