wait for mount point to be ready (#85)

* wait for mount point to be ready

* update tests

cmd/mount.go

@@ -30,8 +30,8 @@ import (
 	"syscall"
 	"time"
 
-	"github.com/VividCortex/godaemon"
 	"github.com/google/gops/agent"
+	"github.com/juicedata/godaemon"
 	"github.com/urfave/cli/v2"
 
 	"github.com/juicedata/juicefs/pkg/chunk"
@@ -41,8 +41,8 @@ import (
 	"github.com/juicedata/juicefs/pkg/vfs"
 )
 
-func MakeDaemon() error {
-	_, _, err := godaemon.MakeDaemon(&godaemon.DaemonAttr{})
+func MakeDaemon(onExit func(int) error) error {
+	_, _, err := godaemon.MakeDaemon(&godaemon.DaemonAttr{OnExit: onExit})
 	return err
 }
 
@@ -136,10 +136,26 @@ func mount(c *cli.Context) error {
 		logger.Fatalf("object storage: %s", err)
 	}
 	logger.Infof("Data use %s", blob)
-	logger.Infof("mount volume %s at %s", format.Name, mp)
+	logger.Infof("Mounting volume %s at %s ...", format.Name, mp)
 
 	if c.Bool("background") {
-		if err := MakeDaemon(); err != nil {
+		err := MakeDaemon(func(stage int) error {
+			if stage != 0 {
+				return nil
+			}
+			for {
+				time.Sleep(time.Millisecond * 50)
+				st, err := os.Stat(mp)
+				if err == nil {
+					if sys, ok := st.Sys().(*syscall.Stat_t); ok && sys.Ino == 1 {
+						logger.Infof("\033[92mOK\033[0m, %s is ready at %s", format.Name, mp)
+						break
+					}
+				}
+			}
+			return nil
+		})
+		if err != nil {
 			logger.Fatalf("Failed to make daemon: %s", err)
 		}
 	}

fstests/Makefile

@@ -19,7 +19,7 @@ setup:
 	redis-server &
 	mkdir -p /jfs
 	../juicefs format -storage mem localhost unittest
-	../juicefs mount --no-usage-report --enable-xattr localhost /jfs &
+	../juicefs mount -d --no-usage-report --enable-xattr localhost /jfs
 
 healthcheck:
 	pgrep juicefs

go.mod

@@ -4,13 +4,13 @@ go 1.13
 
 require (
 	github.com/DataDog/zstd v1.4.5
-	github.com/VividCortex/godaemon v0.0.0-20201215173923-eda977734e72
 	github.com/ceph/go-ceph v0.4.0
 	github.com/go-redis/redis/v8 v8.4.0
 	github.com/google/gops v0.3.13
 	github.com/google/uuid v1.1.1
 	github.com/hanwen/go-fuse/v2 v2.0.4-0.20210104155004-09a3c381714c
 	github.com/hungys/go-lz4 v0.0.0-20170805124057-19ff7f07f099
+	github.com/juicedata/godaemon v0.0.0-20210118074000-659b6681b236
 	github.com/juicedata/juicesync v0.6.3-0.20210114082630-137546625adb
 	github.com/sirupsen/logrus v1.7.0
 	github.com/urfave/cli/v2 v2.3.0

go.sum

@@ -111,6 +111,10 @@ github.com/jmespath/go-jmespath v0.3.0 h1:OS12ieG61fsCg5+qLJ+SsW9NicxNkg3b25OyT2
 github.com/jmespath/go-jmespath v0.3.0/go.mod h1:9QtRXoHjLGCJ5IBSaohpXITPlowMeeYCZ7fLUTSywik=
 github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1:6v2b51hI/fHJwM22ozAgKL4VKDeJcHhJFhtBdhmNjmU=
 github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
+github.com/juicedata/godaemon v0.0.0-20201215173923-eda977734e72 h1:JjGhjAtHA3UQiz3QqrIh31t1LlPI6R54aDrBWSPjfQo=
+github.com/juicedata/godaemon v0.0.0-20201215173923-eda977734e72/go.mod h1:dlxKkLh3qAIPtgr2U/RVzsZJDuXA1ffg+Njikfmhvgw=
+github.com/juicedata/godaemon v0.0.0-20210118074000-659b6681b236 h1:py4S1ZTRfz5hIvrhu83YSw7t0Z621+VrmmZBqSkQn5c=
+github.com/juicedata/godaemon v0.0.0-20210118074000-659b6681b236/go.mod h1:dlxKkLh3qAIPtgr2U/RVzsZJDuXA1ffg+Njikfmhvgw=
 github.com/juicedata/juicesync v0.6.3-0.20210105123925-2af95f8a8472 h1:4IWRyIhlkU2+0UhJcVdLfwjxnBMSj91TIgDN/2E0ikM=
 github.com/juicedata/juicesync v0.6.3-0.20210105123925-2af95f8a8472/go.mod h1:PTOFdso2hrHXU4RctCWgbSysCclKAjcAU311/z55lUE=
 github.com/juicedata/juicesync v0.6.3-0.20210114024648-941ff49f2eb3 h1:JRC/u/wKZvL1Et7vQ5G3uOdy5xWuEYPa/sdnwYt7TmI=