reproduction of golang/go#40846

40846.go

package main

import (
	"context"
	"fmt"
	"math/rand"
	"os"
	"os/signal"
	"syscall"
	"time"

	"bazil.org/fuse"
	"bazil.org/fuse/fs"
)

type testFS struct {
}

// Root implements the fuse.FS interface
func (f *testFS) Root() (fs.Node, error) {
	return &testFSRoot{}, nil
}

type testFSRoot struct {
}

var _ fs.Node = (*testFSRoot)(nil)

// Attr implements the fs.Node interface
func (n *testFSRoot) Attr(_ context.Context, dest *fuse.Attr) error {
	dest.Mode |= 0755 | os.ModeDir
	dest.Inode = 1
	dest.Valid = 0
	return nil
}

var _ fs.NodeGetattrer = (*testFSRoot)(nil)

// Getattr implements the fs.NodeGetattrer interface
func (n *testFSRoot) Getattr(ctx context.Context, req *fuse.GetattrRequest, resp *fuse.GetattrResponse) error {
	select {
	case <-ctx.Done():
		fmt.Printf("interrrupted %v\n", req.ID)
		return ctx.Err()
	case <-time.After(time.Duration(rand.Intn(5)) * time.Second):
	}
	return n.Attr(ctx, &resp.Attr)
}

func main() {
	err := os.MkdirAll("./test", 0755)
	if err != nil {
		panic(err)
	}

	fuse.Debug = func(msg interface{}) {
		fmt.Printf("fuse: %v\n", msg)
	}

	fuseOpts := []fuse.MountOption{
		fuse.AllowNonEmptyMount(), // allow shadowing existing folders
		fuse.AsyncRead(),          // allow simultaneous reads
		fuse.DefaultPermissions(), // use the chmod permissions
	}
	fuseConn, err := fuse.Mount("./test", fuseOpts...)
	if err != nil {
		panic(err)
	}

	go func() {
		err := fs.Serve(fuseConn, &testFS{})
		if err != nil {
			panic(err)
		}
	}()

	stopCh := make(chan struct{})
	go func() {
		c := make(chan os.Signal, 1)
		signal.Notify(c, syscall.SIGUSR2)
		t := time.Tick(100 * time.Microsecond)
		for {
			select {
			case <-stopCh:
				return
			case <-t:
			}
			syscall.Kill(0, syscall.SIGUSR2)
			<-c
		}
	}()

	for i := 0; i < 10; i++ {
		_, err := os.Stat("./test")
		if err != nil {
			fmt.Printf("error: %v\n", err)
			break
		}
		time.Sleep(100 * time.Millisecond)
	}
	close(stopCh)
	for {
		err := fuse.Unmount("./test")
		if err == nil {
			return
		}
		fmt.Println("unmount error", err)
		time.Sleep(time.Second)
	}
}