Do not daemonize on Windows

Author: vitalif

main.go

@@ -23,15 +23,12 @@ import (
 	"os"
 	"os/signal"
 	"strings"
-	"syscall"
 	"time"
 
 	"context"
 
 	"github.com/urfave/cli"
 
-	daemon "github.com/sevlyar/go-daemon"
-
 	"net/http"
 	_ "net/http/pprof"
 )
@@ -99,47 +96,25 @@ func main() {
 			flags.Cleanup()
 		}()
 
-		var notifier *ParentNotifier
-		if !flags.Foreground {
-			notifier = NewParentNotifier()
-
-			messageArg0()
-
-			ctx := new(daemon.Context)
-			if flags.LogFile == "stderr" || flags.LogFile == "/dev/stderr" {
-				ctx.LogFileName = "/dev/stderr"
+		var daemonizer *Daemonizer
+		if !canDaemonize {
+			flags.Foreground = true
+		}
+		if flags.LogFile == "" {
+			if flags.Foreground {
+				flags.LogFile = "stderr"
+			} else {
+				flags.LogFile = "syslog"
 			}
-			child, err = ctx.Reborn()
-
+		}
+		if !flags.Foreground {
+			daemonizer = NewDaemonizer()
+			err := daemonizer.Daemonize(flags.LogFile)
 			if err != nil {
-				panic(fmt.Sprintf("unable to daemonize: %v", err))
+				return err
 			}
-
-			if flags.LogFile == "" {
-				if flags.Foreground || child != nil {
-					flags.LogFile = "stderr"
-				} else {
-					flags.LogFile = "syslog"
-				}
-			}
-
-			InitLoggers(flags.LogFile)
-
-			if child != nil {
-				// attempt to wait for child to notify parent
-				if notifier.Wait() {
-					return
-				} else {
-					return syscall.EINVAL
-				}
-			} else {
-				notifier.Cancel()
-				defer ctx.Release()
-			}
-
-		} else {
-			InitLoggers(flags.LogFile)
 		}
+		InitLoggers(flags.LogFile)
 
 		pprof := flags.PProf
 		if pprof == "" && os.Getenv("PPROF") != "" {
@@ -163,13 +138,13 @@ func main() {
 
 		if err != nil {
 			if !flags.Foreground {
-				notifier.Notify(false)
+				daemonizer.NotifySuccess(false)
 			}
 			log.Fatalf("Mounting file system: %v", err)
 			// fatal also terminates itself
 		} else {
 			if !flags.Foreground {
-				notifier.Notify(true)
+				daemonizer.NotifySuccess(true)
 			}
 			log.Println("File system has been successfully mounted.")
 			// Let the user unmount with Ctrl-C (SIGINT)

main_nowindows.go

@@ -25,7 +25,9 @@ import (
 	"strings"
 	"sync"
 	"syscall"
+
 	"github.com/kardianos/osext"
+	daemon "github.com/sevlyar/go-daemon"
 
 	"github.com/yandex-cloud/geesefs/api/common"
 	"github.com/yandex-cloud/geesefs/internal"
@@ -52,13 +54,15 @@ func kill(pid int, s os.Signal) (err error) {
 	return
 }
 
-type ParentNotifier struct {
+const canDaemonize = true
+
+type Daemonizer struct {
 	result os.Signal
 	wg sync.WaitGroup
 }
 
-func NewParentNotifier() *ParentNotifier {
-	p := &ParentNotifier{}
+func NewDaemonizer() *Daemonizer {
+	p := &Daemonizer{}
 
 	signalChan := make(chan os.Signal, 1)
 	signal.Notify(signalChan, syscall.SIGUSR1, syscall.SIGUSR2)
@@ -72,18 +76,46 @@ func NewParentNotifier() *ParentNotifier {
 	return p
 }
 
-func (p *ParentNotifier) Cancel() {
+func (p *Daemonizer) Daemonize(logFile string) error {
+	messageArg0()
+
+	ctx := new(daemon.Context)
+	if logFile == "stderr" || logFile == "/dev/stderr" {
+		ctx.LogFileName = "/dev/stderr"
+	}
+	child, err := ctx.Reborn()
+
+	if err != nil {
+		panic(fmt.Sprintf("unable to daemonize: %v", err))
+	}
+
+	if child != nil {
+		// attempt to wait for child to notify parent
+		if p.Wait() {
+			os.Exit(0)
+		} else {
+			return syscall.EINVAL
+		}
+	} else {
+		p.Cancel()
+		defer ctx.Release()
+	}
+
+	return nil
+}
+
+func (p *Daemonizer) Cancel() {
 	// kill our own waiting goroutine
 	kill(os.Getpid(), syscall.SIGUSR1)
 	p.wg.Wait()
 }
 
-func (p *ParentNotifier) Wait() bool {
+func (p *Daemonizer) Wait() bool {
 	p.wg.Wait()
 	return p.result == syscall.SIGUSR1
 }
 
-func (p *ParentNotifier) Notify(success bool) {
+func (p *Daemonizer) NotifySuccess(success bool) {
 	sig := syscall.SIGUSR1
 	if !success {
 		sig = syscall.SIGUSR2

main_windows.go

@@ -29,21 +29,27 @@ func isSigUsr1(s os.Signal) bool {
 	return false
 }
 
-type ParentNotifier struct {
+const canDaemonize = false
+
+type Daemonizer struct {
+}
+
+func NewDaemonizer() *Daemonizer {
+	return &Daemonizer{}
 }
 
-func NewParentNotifier() *ParentNotifier {
-	return &ParentNotifier{}
+func (p *Daemonizer) Daemonize(logFile string) error {
+	return nil
 }
 
-func (p *ParentNotifier) Cancel() {
+func (p *Daemonizer) Cancel() {
 }
 
-func (p *ParentNotifier) Wait() bool {
+func (p *Daemonizer) Wait() bool {
 	return true
 }
 
-func (p *ParentNotifier) Notify(success bool) {
+func (p *Daemonizer) NotifySuccess(success bool) {
 }
 
 // Mount the file system based on the supplied arguments, returning a