[PULL 2/7] tests/9pfs: Twalk with nwname=0

[Christian Schoenebeck <qemu_oss@crudebyte.com>]

Send Twalk request with nwname=0. In this case no QIDs should
be returned by 9p server; this is equivalent to walking to dot.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <b5ead2775000203607801f09bcefc04c493d8bfa.1647339025.git.qemu_oss@crudebyte.com>
---
 tests/qtest/virtio-9p-test.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/tests/qtest/virtio-9p-test.c b/tests/qtest/virtio-9p-test.c
index b3837546be..7942d5fef9 100644
--- a/tests/qtest/virtio-9p-test.c
+++ b/tests/qtest/virtio-9p-test.c
@@ -1002,6 +1002,27 @@ static void fs_walk_nonexistent(void *obj, void *data, QGuestAllocator *t_alloc)
     do_walk_expect_error(v9p, "non-existent", ENOENT);
 }
 
+static void fs_walk_none(void *obj, void *data, QGuestAllocator *t_alloc)
+{
+    QVirtio9P *v9p = obj;
+    alloc = t_alloc;
+    v9fs_qid root_qid;
+    g_autofree v9fs_qid *wqid = NULL;
+    P9Req *req;
+
+    do_version(v9p);
+    req = v9fs_tattach(v9p, 0, getuid(), 0);
+    v9fs_req_wait_for_reply(req, NULL);
+    v9fs_rattach(req, &root_qid);
+
+    req = v9fs_twalk(v9p, 0, 1, 0, NULL, 0);
+    v9fs_req_wait_for_reply(req, NULL);
+    v9fs_rwalk(req, NULL, &wqid);
+
+    /* special case: no QID is returned if nwname=0 was sent */
+    g_assert(wqid == NULL);
+}
+
 static void fs_walk_dotdot(void *obj, void *data, QGuestAllocator *t_alloc)
 {
     QVirtio9P *v9p = obj;
@@ -1435,6 +1456,7 @@ static void register_virtio_9p_test(void)
     qos_add_test("synth/walk/basic", "virtio-9p", fs_walk,  &opts);
     qos_add_test("synth/walk/no_slash", "virtio-9p", fs_walk_no_slash,
                   &opts);
+    qos_add_test("synth/walk/none", "virtio-9p", fs_walk_none, &opts);
     qos_add_test("synth/walk/dotdot_from_root", "virtio-9p",
                  fs_walk_dotdot,  &opts);
     qos_add_test("synth/walk/non_existent", "virtio-9p", fs_walk_nonexistent,
-- 
2.30.2