From 2dd38978aa183d4ce5a70f538afa11c0414b34da Mon Sep 17 00:00:00 2001
From: ethan <ethan@juicedata.io>
Date: Fri, 14 Feb 2025 19:43:40 +0800
Subject: [PATCH] Windows: add option to startup juicefs as system service. fix
 #347, link #1546 (#5643)

---
 cmd/mount.go         |  3 ++
 cmd/mount_windows.go |  8 +++--
 pkg/winfsp/winfs.go  | 69 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 78 insertions(+), 2 deletions(-)

diff --git a/cmd/mount.go b/cmd/mount.go
index 994626ec36e5..68bb5936e0d7 100644
--- a/cmd/mount.go
+++ b/cmd/mount.go
@@ -676,6 +676,9 @@ func mount(c *cli.Context) error {
 		}
 		os.Setenv("JFS_SUPERVISOR", strconv.Itoa(os.Getppid()))
 		return launchMount(mp, vfsConf)
+	} else if runtime.GOOS == "windows" && c.Bool("background") {
+		daemonRun(c, addr, vfsConf)
+		return nil
 	}
 	logger.Infof("JuiceFS version %s", version.Version())
 
diff --git a/cmd/mount_windows.go b/cmd/mount_windows.go
index 9b65c2aa68b0..a73eba23dae1 100644
--- a/cmd/mount_windows.go
+++ b/cmd/mount_windows.go
@@ -47,12 +47,16 @@ func mountFlags() []cli.Flag {
 			Name:  "delay-close",
 			Usage: "delay file closing in seconds.",
 		},
+		&cli.BoolFlag{
+			Name:  "d",
+			Aliases: []string{"background"},
+			Usage: "run in background(Windows: as a system service. support ONLY 1 volume mounting at the same time)",
+		},
 	}
 }
 
 func makeDaemon(c *cli.Context, conf *vfs.Config) error {
-	logger.Warnf("Cannot run in background in Windows.")
-	return nil
+	return winfsp.RunAsSystemSerivce(conf.Format.Name, c.Args().Get(1))
 }
 
 func makeDaemonForSvc(c *cli.Context, m meta.Meta, metaUrl, listenAddr string) error {
diff --git a/pkg/winfsp/winfs.go b/pkg/winfsp/winfs.go
index 9e778a3d1ee2..5dbbc8f82a19 100644
--- a/pkg/winfsp/winfs.go
+++ b/pkg/winfsp/winfs.go
@@ -22,6 +22,7 @@ package winfsp
 import (
 	"fmt"
 	"os"
+	"os/exec"
 	"path"
 	"runtime"
 	"strings"
@@ -35,6 +36,8 @@ import (
 	"github.com/juicedata/juicefs/pkg/meta"
 	"github.com/juicedata/juicefs/pkg/utils"
 	"github.com/juicedata/juicefs/pkg/vfs"
+
+	"golang.org/x/sys/windows/registry"
 )
 
 var logger = utils.GetLogger("juicefs")
@@ -669,3 +672,69 @@ func Serve(v *vfs.VFS, fuseOpt string, fileCacheTo float64, asRoot bool, delayCl
 	logger.Debugf("mount point: %s, options: %s", conf.Meta.MountPoint, options)
 	_ = host.Mount(conf.Meta.MountPoint, []string{"-o", options})
 }
+
+func RunAsSystemSerivce(name string, mountpoint string) error {
+	// https://winfsp.dev/doc/WinFsp-Service-Architecture/
+	logger.Info("Running as Windows system service.")
+
+	var cmds []string
+	for _, v := range os.Args[1:] {
+		if v == "-d" || v == "--background" {
+			continue
+		}
+		cmds = append(cmds, v)
+	}
+
+	cmdLine := strings.Join(cmds, " ")
+
+	regKeyPath := "SOFTWARE\\WOW6432Node\\WinFsp\\Services\\juicefs"
+	k, err := registry.OpenKey(registry.LOCAL_MACHINE, regKeyPath, registry.ALL_ACCESS)
+	if err != nil {
+		if err == syscall.ERROR_FILE_NOT_FOUND || err == syscall.ERROR_PATH_NOT_FOUND {
+			logger.Info("Registry key not found, create it")
+			k, _, err = registry.CreateKey(registry.LOCAL_MACHINE, regKeyPath, registry.ALL_ACCESS)
+			if err != nil {
+				return fmt.Errorf("Failed to create registry key: %s", err)
+			}
+		} else {
+			return fmt.Errorf("Failed to open registry key: %s", err)
+		}
+	}
+	defer k.Close()
+
+	err = k.SetStringValue("CommandLine", cmdLine)
+	if err != nil {
+		return fmt.Errorf("Failed to set registry key: %s", err)
+	}
+
+	securityDescriptor := "D:P(A;;RPWPLC;;;WD)"
+	err = k.SetStringValue("Security", securityDescriptor)
+	if err != nil {
+		return fmt.Errorf("Failed to set registry key: %s", err)
+	}
+
+	filePath, err := os.Executable()
+	if err != nil {
+		return fmt.Errorf("Failed to get current file path: %s", err)
+	}
+
+	err = k.SetStringValue("Executable", filePath)
+	if err != nil {
+		return fmt.Errorf("Failed to set registry key: %s", err)
+	}
+
+	err = k.SetDWordValue("JobControl", 1)
+	if err != nil {
+		return fmt.Errorf("Failed to set registry key: %s", err)
+	}
+
+	logger.Debug("Starting juicefs service.")
+	cmd := exec.Command("net", "use", mountpoint, "\\\\juicefs\\"+name)
+	err = cmd.Run()
+	if err != nil {
+		return fmt.Errorf("Failed to mount juicefs: %s", err)
+	}
+
+	logger.Info("Juicefs system service started successfully.")
+	return nil
+}