logrotate.go

package main

import (
	"io"
	"log"
	"os"
)

func initLogging() {
	// Set default logging pattern.
	log.SetFlags(log.LstdFlags)

	// Add C for child and P for parent.
	if isChild {
		log.SetPrefix("C ")
		// Set log output of child to stdout.
		log.SetOutput(os.Stdout)
		return
	}
	log.SetPrefix("P ")

	// Return if no log file should be written. Logging will still be done to stdout.
	if config.LogFile == "" {
		return
	}

	// Open the log file for appending.
	f, err := os.OpenFile(config.LogFile, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
	if err != nil {
		log.Fatal(err)
	}
	// Do not close the file, because the logger should always be able to write into it!
	// defer f.Close()

	// Create a writer that writes to the log file and to stdout.
	w := io.MultiWriter(f, os.Stdout)

	// Modify the output of the default logger.
	log.SetOutput(w)

	/*
		// Log rotation only works, when the server is not in a jail.
		// TODO: move logging into parent
		if !config.JailProcess {
			// Rotate the log files every day.
			go func() {
				for range time.Tick(24 * time.Hour) {
					fileInfo, err := f.Stat()
					if err == nil && fileInfo.Size() < 5*1024*1024 {
						// Only rotate log files if they are too big.
						continue
					}

					// Remove the oldest log file.
					os.Remove(config.LogFile + ".3")

					// Closing the current log file is not necessary,
					// because os.Rename() closes the file automatically.
					// f.Close()

					// Rename the log files.
					os.Rename(config.LogFile+".2", config.LogFile+".3")
					os.Rename(config.LogFile+".1", config.LogFile+".2")
					os.Rename(config.LogFile, config.LogFile+".1")

					// Create a new log file.
					f, err := os.Create(config.LogFile)
					if err != nil {
						log.Fatal(err)
					}

					// Create a writer that writes to the log file and to stdout.
					w = io.MultiWriter(f, os.Stdout)

					// Modify the output of the default logger.
					log.SetOutput(w)
				}
			}()
		}


		////// OR something like this:


		// Rotate the log files every day.
		go func() {
			for range time.Tick(24 * time.Hour) {
				// Check if the log file size exceeds a threshold before rotating
				fileInfo, err := f.Stat()
				if err != nil || fileInfo.Size() >= 5*1024*1024 {
					rotateLogs()
				}
			}
		}()

		func rotateLogs() {
			// Remove the oldest log file.
			os.Remove(config.LogFile + ".3")
			os.Rename(config.LogFile+".2", config.LogFile+".3")
			os.Rename(config.LogFile+".1", config.LogFile+".2")
			os.Rename(config.LogFile, config.LogFile+".1")

			// Create a new log file.
			f, err := os.Create(config.LogFile)
			if err != nil {
				log.Fatal(err)
			}

			// Create a writer that writes to the log file and to stdout.
			w := io.MultiWriter(f, os.Stdout)

			// Modify the output of the default logger.
			log.SetOutput(w)
		}



	*/

}