Use local "ensureRemoveAll" instead of docker/pkg/system

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

pkg/server/helpers_windows.go

@@ -19,9 +19,11 @@ limitations under the License.
 package server
 
 import (
+	"context"
 	"os"
 	"path/filepath"
 	"syscall"
+	"time"
 )
 
 // openLogFile opens/creates a container log file.
@@ -156,3 +158,62 @@ func fixLongPath(path string) string {
 	}
 	return string(pathbuf[:w])
 }
+
+// ensureRemoveAll wraps `os.RemoveAll` to check for specific errors that can
+// often be remedied.
+// Only use `ensureRemoveAll` if you really want to make every effort to remove
+// a directory.
+//
+// Because of the way `os.Remove` (and by extension `os.RemoveAll`) works, there
+// can be a race between reading directory entries and then actually attempting
+// to remove everything in the directory.
+// These types of errors do not need to be returned since it's ok for the dir to
+// be gone we can just retry the remove operation.
+//
+// This should not return a `os.ErrNotExist` kind of error under any circumstances
+func ensureRemoveAll(_ context.Context, dir string) error {
+	notExistErr := make(map[string]bool)
+
+	// track retries
+	exitOnErr := make(map[string]int)
+	maxRetry := 50
+
+	for {
+		err := os.RemoveAll(dir)
+		if err == nil {
+			return nil
+		}
+
+		pe, ok := err.(*os.PathError)
+		if !ok {
+			return err
+		}
+
+		if os.IsNotExist(err) {
+			if notExistErr[pe.Path] {
+				return err
+			}
+			notExistErr[pe.Path] = true
+
+			// There is a race where some subdir can be removed but after the
+			// parent dir entries have been read.
+			// So the path could be from `os.Remove(subdir)`
+			// If the reported non-existent path is not the passed in `dir` we
+			// should just retry, but otherwise return with no error.
+			if pe.Path == dir {
+				return nil
+			}
+			continue
+		}
+
+		if pe.Err != syscall.EBUSY {
+			return err
+		}
+
+		if exitOnErr[pe.Path] == maxRetry {
+			return err
+		}
+		exitOnErr[pe.Path]++
+		time.Sleep(100 * time.Millisecond)
+	}
+}