tests: add fd leak retry logic to UnmountErr, really return error

Give the gocryptfs process one extra millisecond to close
files. Allows us to drop several other sleeps.

UnmountErr now really returns an error when it detects an fd leak
instead of just printing a message.

1 files changed, 10 insertions, 2 deletions

diff --git a/tests/test_helpers/mount_unmount.go b/tests/test_helpers/mount_unmount.go
index 1142666..cce763a 100644
--- a/tests/test_helpers/mount_unmount.go
+++ b/tests/test_helpers/mount_unmount.go
@@ -141,14 +141,22 @@ func UnmountErr(dir string) (err error) {
 	for i := 1; i <= max; i++ {
 		if pid > 0 {
 			fdsNow = ListFds(pid)
+			if len(fdsNow) > len(fds) {
+				// File close on FUSE is asynchronous, closing a socket
+				// when testing -ctlsock as well. Wait one extra millisecond
+				// and hope that all close commands get through to the gocryptfs
+				// process.
+				time.Sleep(1 * time.Millisecond)
+				fdsNow = ListFds(pid)
+			}
 		}
 		cmd := exec.Command(UnmountScript, "-u", dir)
 		cmd.Stdout = os.Stdout
 		cmd.Stderr = os.Stderr
 		err = cmd.Run()
 		if err == nil {
-			if pid > 0 && len(fdsNow) > len(fds) {
-				fmt.Printf("FD leak? Details:\nold=%v \nnew=%v\n", fds, fdsNow)
+			if len(fdsNow) > len(fds) {
+				return fmt.Errorf("FD leak? pid=%d dir=%q, fds:\nold=%v \nnew=%v\n", pid, dir, fds, fdsNow)
 			}
 			return nil
 		}