package s3 import ( "fmt" "io/ioutil" "os" "os/exec" "strings" "syscall" "time" "github.com/mitchellh/go-ps" "github.com/golang/glog" ) func waitForProcess(p *os.Process, backoff int) error { if backoff == 20 { return fmt.Errorf("Timeout waiting for PID %v to end", p.Pid) } cmdLine, err := getCmdLine(p.Pid) if err != nil { glog.Warningf("Error checking cmdline of PID %v, assuming it is dead: %s", p.Pid, err) return nil } if cmdLine == "" { // ignore defunct processes // TODO: debug why this happens in the first place // seems to only happen on k8s, not on local docker glog.Warning("Fuse process seems dead, returning") return nil } if err := p.Signal(syscall.Signal(0)); err != nil { glog.Warningf("Fuse process does not seem active or we are unprivileged: %s", err) return nil } glog.Infof("Fuse process with PID %v still active, waiting...", p.Pid) time.Sleep(time.Duration(backoff*100) * time.Millisecond) return waitForProcess(p, backoff+1) } func findFuseMountProcess(path string, name string) (*os.Process, error) { processes, err := ps.Processes() if err != nil { return nil, err } for _, p := range processes { if strings.Contains(p.Executable(), name) { cmdLine, err := getCmdLine(p.Pid()) if err != nil { glog.Errorf("Unable to get cmdline of PID %v: %s", p.Pid(), err) continue } if strings.Contains(cmdLine, path) { glog.Infof("Found matching pid %v on path %s", p.Pid(), path) return os.FindProcess(p.Pid()) } } } return nil, nil } func getCmdLine(pid int) (string, error) { cmdLineFile := fmt.Sprintf("/proc/%v/cmdline", pid) cmdLine, err := ioutil.ReadFile(cmdLineFile) if err != nil { return "", err } return string(cmdLine), nil } func createLoopDevice(device string) error { if _, err := os.Stat(device); !os.IsNotExist(err) { return nil } args := []string{ device, "b", "7", "0", } cmd := exec.Command("mknod", args...) out, err := cmd.CombinedOutput() if err != nil { return fmt.Errorf("Error configuring loop device: %s", out) } return nil }