i2pd/libi2pd/Log.h
2023-03-30 21:31:12 +00:00

226 lines
5.1 KiB
C++

/*
* Copyright (c) 2013-2020, The PurpleI2P Project
*
* This file is part of Purple i2pd project and licensed under BSD3
*
* See full license text in LICENSE file at top of project tree
*/
#ifndef LOG_H__
#define LOG_H__
#include <ctime>
#include <string>
#include <iostream>
#include <fstream>
#include <sstream>
#include <chrono>
#include <memory>
#include <thread>
#include <functional>
#include "Queue.h"
#ifndef _WIN32
#include <syslog.h>
#endif
enum LogLevel
{
eLogNone = 0,
eLogCritical,
eLogError,
eLogWarning,
eLogInfo,
eLogDebug,
eNumLogLevels
};
enum LogType {
eLogStdout = 0,
eLogStream,
eLogFile,
#ifndef _WIN32
eLogSyslog,
#endif
};
namespace i2p {
namespace log {
struct LogMsg; /* forward declaration */
class Log
{
private:
enum LogType m_Destination;
enum LogLevel m_MinLevel;
std::shared_ptr<std::ostream> m_LogStream;
std::string m_Logfile;
std::time_t m_LastTimestamp;
char m_LastDateTime[64];
i2p::util::Queue<std::shared_ptr<LogMsg> > m_Queue;
bool m_HasColors;
std::string m_TimeFormat;
volatile bool m_IsRunning;
std::thread * m_Thread;
private:
/** prevent making copies */
Log (const Log &);
const Log& operator=(const Log&);
void Run ();
void Process (std::shared_ptr<LogMsg> msg);
/**
* @brief Makes formatted string from unix timestamp
* @param ts Second since epoch
*
* This function internally caches the result for last provided value
*/
const char * TimeAsString(std::time_t ts);
public:
Log ();
~Log ();
LogType GetLogType () { return m_Destination; };
LogLevel GetLogLevel () { return m_MinLevel; };
void Start ();
void Stop ();
/**
* @brief Sets minimal allowed level for log messages
* @param level String with wanted minimal msg level
*/
void SetLogLevel (const std::string& level);
/**
* @brief Sets log destination to logfile
* @param path Path to logfile
*/
void SendTo (const std::string &path);
/**
* @brief Sets log destination to given output stream
* @param os Output stream
*/
void SendTo (std::shared_ptr<std::ostream> os);
/**
* @brief Sets format for timestamps in log
* @param format String with timestamp format
*/
void SetTimeFormat (std::string format) { m_TimeFormat = format; };
#ifndef _WIN32
/**
* @brief Sets log destination to syslog
* @param name Wanted program name
* @param facility Wanted log category
*/
void SendTo (const char *name, int facility);
#endif
/**
* @brief Format log message and write to output stream/syslog
* @param msg Pointer to processed message
*/
void Append(std::shared_ptr<i2p::log::LogMsg> &);
/** @brief Reopen log file */
void Reopen();
};
/**
* @struct LogMsg
* @brief Log message container
*
* We creating it somewhere with LogPrint(),
* then put in MsgQueue for later processing.
*/
struct LogMsg {
std::time_t timestamp;
std::string text; /**< message text as single string */
LogLevel level; /**< message level */
std::thread::id tid; /**< id of thread that generated message */
LogMsg (LogLevel lvl, std::time_t ts, std::string&& txt): timestamp(ts), text(std::move(txt)), level(lvl) {}
};
Log & Logger();
typedef std::function<void (const std::string&)> ThrowFunction;
ThrowFunction GetThrowFunction ();
void SetThrowFunction (ThrowFunction f);
} // log
} // i2p
/** internal usage only -- folding args array to single string */
template<typename TValue>
void LogPrint (std::stringstream& s, TValue&& arg) noexcept
{
s << std::forward<TValue>(arg);
}
#if (__cplusplus < 201703L) // below C++ 17
/** internal usage only -- folding args array to single string */
template<typename TValue, typename... TArgs>
void LogPrint (std::stringstream& s, TValue&& arg, TArgs&&... args) noexcept
{
LogPrint (s, std::forward<TValue>(arg));
LogPrint (s, std::forward<TArgs>(args)...);
}
#endif
/**
* @brief Create log message and send it to queue
* @param level Message level (eLogError, eLogInfo, ...)
* @param args Array of message parts
*/
template<typename... TArgs>
void LogPrint (LogLevel level, TArgs&&... args) noexcept
{
i2p::log::Log &log = i2p::log::Logger();
if (level > log.GetLogLevel ())
return;
// fold message to single string
std::stringstream ss;
#if (__cplusplus >= 201703L) // C++ 17 or higher
(LogPrint (ss, std::forward<TArgs>(args)), ...);
#else
LogPrint (ss, std::forward<TArgs>(args)...);
#endif
auto msg = std::make_shared<i2p::log::LogMsg>(level, std::time(nullptr), std::move(ss).str());
msg->tid = std::this_thread::get_id();
log.Append(msg);
}
/**
* @brief Throw fatal error message with the list of arguments
* @param args Array of message parts
*/
template<typename... TArgs>
void ThrowFatal (TArgs&&... args) noexcept
{
auto f = i2p::log::GetThrowFunction ();
if (!f) return;
// fold message to single string
std::stringstream ss("");
#if (__cplusplus >= 201703L) // C++ 17 or higher
(LogPrint (ss, std::forward<TArgs>(args)), ...);
#else
LogPrint (ss, std::forward<TArgs>(args)...);
#endif
f (ss.str ());
}
#endif // LOG_H__