vm: improve inotify file comparison (abiosoft#656)

daemon/process/inotify/watch.go

@@ -11,21 +11,26 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
+type modTime struct {
+	path string // filename
+	time.Time
+}
+
 func (f *inotifyProcess) watchFiles(ctx context.Context) error {
 	log := f.log
 	log.Trace("begin inotify watcher")
 
 	fileMap := map[string]time.Time{}
-	changed := make(chan string)
+	mod := make(chan modTime)
 
-	go func(changed chan string) {
+	go func(mod chan modTime) {
 		var last time.Time
 		for {
 			select {
 			case <-ctx.Done():
-				close(changed)
+				close(mod)
 				return
-			case path := <-changed:
+			case ev := <-mod:
 				now := time.Now()
 				if now.Sub(last) < time.Millisecond*500 {
 					continue
@@ -34,15 +39,15 @@ func (f *inotifyProcess) watchFiles(ctx context.Context) error {
 
 				// construct date time in the format YYYY-MM-DD HH:MM:SS
 				// for busybox
-				t := now.Add(-5 * time.Second).Format("2006-01-02 15:04:05")
-				log.Infof("setting modtime to %s for %s ", t, path)
-				if err := f.guest.Run("/bin/touch", "-d", t, path); err != nil {
+				t := ev.Format("2006-01-02 15:04:05")
+				log.Infof("setting modtime to %s for %s ", t, ev.path)
+				if err := f.guest.Run("/bin/touch", "-d", t, ev.path); err != nil {
 					log.Error(err)
 				}
 			}
 
 		}
-	}(changed)
+	}(mod)
 
 	for {
 		select {
@@ -65,14 +70,14 @@ func (f *inotifyProcess) watchFiles(ctx context.Context) error {
 				continue
 			}
 
-			if err := doWatch(dirs, fileMap, changed); err != nil {
+			if err := doWatch(dirs, fileMap, mod); err != nil {
 				log.Errorf("error during directory watch: %v", err)
 			}
 		}
 	}
 }
 
-func doWatch(dirs []string, fileMap map[string]time.Time, changed chan<- string) error {
+func doWatch(dirs []string, fileMap map[string]time.Time, changed chan<- modTime) error {
 	for _, dir := range dirs {
 		err := filepath.WalkDir(dir, func(path string, d fs.DirEntry, err error) error {
 			if err != nil {
@@ -97,10 +102,10 @@ func doWatch(dirs []string, fileMap map[string]time.Time, changed chan<- string)
 			currentTime, ok := fileMap[path]
 			newTime := info.ModTime()
 
-			if ok && newTime.After(currentTime) {
+			if ok && newTime.After(currentTime.Add(time.Millisecond*500)) {
 				go func(path string) {
 					logrus.Tracef("changed file modTime %v->%v: %s", currentTime, newTime, path)
-					changed <- path
+					changed <- modTime{path: path, Time: newTime}
 				}(path)
 			}