kde-lockscreen-suspend-display/cmd/after-lock/after-lock.go

package main

import (
	"kdelsd/afterlock"
	"kdelsd/config"
	"kdelsd/lockfile"
	"kdelsd/xdg/display"
	"kdelsd/xdg/keypressdetector"
	"kdelsd/xdg/lockscreen"
	"log"
	"os"
	"os/signal"
	"runtime/debug"
	"syscall"
)


type afterLockConfig struct {
	INITIAL_DELAY int
	LOOP_DELAY int
	DEV_NODE string
	LOCK_PATH string
	LOG_PATH string
	PRINT_STACKTRACES bool
}

var configuration = afterLockConfig{
	INITIAL_DELAY: 3,
	LOOP_DELAY: 7,
	LOCK_PATH: "/tmp/after-lock.lock",
	PRINT_STACKTRACES: true,
}

var mainDone chan bool
var cleanupDone chan bool
var sig chan os.Signal


func init() {
	mainDone = make(chan bool)
	cleanupDone = make(chan bool)
	sig = make(chan os.Signal)
}


func main() {
	defer handleErrors()
	err := config.Build("AFL", &configuration)
	if err != nil {
		panic(err)
	}
	f := initLogging(configuration.LOG_PATH)
	if f == nil {
		panic("Failed to open logfile")
	}
	initCleanup(grabExclusiveProcessLock(configuration.LOCK_PATH), f)

	al := buildAfterlock()
	al.Start()

	mainDone<-true
	<-cleanupDone
}

func handleErrors() {
	if err := recover(); err != nil {
		log.Printf("Crashed with unexpected error: %v!\n", err)
		if configuration.PRINT_STACKTRACES {
			log.Printf("Stack trace:\n\n")
			debug.PrintStack()
		}
		os.Exit(1)
	}
}

func grabExclusiveProcessLock(lockfile_path string) *lockfile.Lockfile {
	lf := lockfile.New(lockfile_path)
	err := lf.Lock()
	if err != nil {
		panic(err)
	}
	return lf
}

func initCleanup(lock *lockfile.Lockfile, logfile *os.File) {
	signal.Notify(sig, syscall.SIGINT, syscall.SIGTERM)

	go func() {
		select{
		case <-mainDone:
		case <-sig:
		}

		lock.Unlock()
		teardownLogging(logfile)

		cleanupDone<-true
	}()
}

func buildAfterlock() *afterlock.AfterLock {
	al := afterlock.New(configuration.DEV_NODE)
	al.InitialDelay = uint(configuration.INITIAL_DELAY)
	al.LoopDelay = uint(configuration.LOOP_DELAY)
	al.Display = display.Xset{}
	al.LockScreen = lockscreen.XDG{}
	al.KeypressDetector = keypressdetector.Evdev{}
	return al
}