[PATCH v4 06/11] tests/virtio-9p: added splitted readdir test

[Christian Schoenebeck <qemu_oss@crudebyte.com>]

The previous, already existing readdir test simply used a 'count'
parameter big enough to retrieve all directory entries with a
single Treaddir request.

In this new 'splitted' readdir test, directory entries are
retrieved, splitted over several Treaddir requests by picking small
'count' parameters which force the server to truncate the response.
So the test client sends as many Treaddir requests as necessary to
get all directory entries. Currently this test covers actually two
tests: a sequence of Treaddir requests with count=512 and then a
subsequent test with a sequence of Treaddir requests with count=256.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
---
 tests/qtest/virtio-9p-test.c | 91 ++++++++++++++++++++++++++++++++++++
 1 file changed, 91 insertions(+)

diff --git a/tests/qtest/virtio-9p-test.c b/tests/qtest/virtio-9p-test.c
index 2167322985..8b0d94546e 100644
--- a/tests/qtest/virtio-9p-test.c
+++ b/tests/qtest/virtio-9p-test.c
@@ -578,6 +578,7 @@ static bool fs_dirents_contain_name(struct V9fsDirent *e, const char* name)
     return false;
 }
 
+/* basic readdir test where reply fits into a single response message */
 static void fs_readdir(void *obj, void *data, QGuestAllocator *t_alloc)
 {
     QVirtio9P *v9p = obj;
@@ -631,6 +632,95 @@ static void fs_readdir(void *obj, void *data, QGuestAllocator *t_alloc)
     g_free(wnames[0]);
 }
 
+/* readdir test where overall request is splitted over several messages */
+static void fs_readdir_split(void *obj, void *data, QGuestAllocator *t_alloc)
+{
+    QVirtio9P *v9p = obj;
+    alloc = t_alloc;
+    char *const wnames[] = { g_strdup(QTEST_V9FS_SYNTH_READDIR_DIR) };
+    uint16_t nqid;
+    v9fs_qid qid;
+    uint32_t count, nentries, npartialentries;
+    struct V9fsDirent *entries, *tail, *partialentries;
+    P9Req *req;
+    int subtest;
+    int fid;
+    uint64_t offset;
+    /* the Treaddir 'count' parameter values to be tested */
+    const uint32_t vcount[] = { 512, 256 };
+    const int nvcount = sizeof(vcount) / sizeof(uint32_t);
+
+    fs_attach(v9p, NULL, t_alloc);
+
+    /* iterate over all 'count' parameter values to be tested with Treaddir */
+    for (subtest = 0; subtest < nvcount; ++subtest) {
+        fid = subtest + 1;
+        offset = 0;
+        entries = NULL;
+        nentries = 0;
+        tail = NULL;
+
+        req = v9fs_twalk(v9p, 0, fid, 1, wnames, 0);
+        v9fs_req_wait_for_reply(req, NULL);
+        v9fs_rwalk(req, &nqid, NULL);
+        g_assert_cmpint(nqid, ==, 1);
+
+        req = v9fs_tlopen(v9p, fid, O_DIRECTORY, 0);
+        v9fs_req_wait_for_reply(req, NULL);
+        v9fs_rlopen(req, &qid, NULL);
+
+        /*
+         * send as many Treaddir requests as required to get all directory
+         * entries
+         */
+        while (true) {
+            npartialentries = 0;
+            partialentries = NULL;
+
+            req = v9fs_treaddir(v9p, fid, offset, vcount[subtest], 0);
+            v9fs_req_wait_for_reply(req, NULL);
+            v9fs_rreaddir(req, &count, &npartialentries, &partialentries);
+            if (npartialentries > 0 && partialentries) {
+                if (!entries) {
+                    entries = partialentries;
+                    nentries = npartialentries;
+                    tail = partialentries;
+                } else {
+                    tail->next = partialentries;
+                    nentries += npartialentries;
+                }
+                while (tail->next) {
+                    tail = tail->next;
+                }
+                offset = tail->offset;
+            } else {
+                break;
+            }
+        }
+
+        g_assert_cmpint(
+            nentries, ==,
+            QTEST_V9FS_SYNTH_READDIR_NFILES + 2 /* "." and ".." */
+        );
+
+        /*
+         * Check all file names exist in returned entries, ignore their order
+         * though.
+         */
+        g_assert_cmpint(fs_dirents_contain_name(entries, "."), ==, true);
+        g_assert_cmpint(fs_dirents_contain_name(entries, ".."), ==, true);
+        for (int i = 0; i < QTEST_V9FS_SYNTH_READDIR_NFILES; ++i) {
+            char *name = g_strdup_printf(QTEST_V9FS_SYNTH_READDIR_FILE, i);
+            g_assert_cmpint(fs_dirents_contain_name(entries, name), ==, true);
+            g_free(name);
+        }
+
+        v9fs_free_dirents(entries);
+    }
+
+    g_free(wnames[0]);
+}
+
 static void fs_walk_no_slash(void *obj, void *data, QGuestAllocator *t_alloc)
 {
     QVirtio9P *v9p = obj;
@@ -810,6 +900,7 @@ static void register_virtio_9p_test(void)
     qos_add_test("fs/flush/ignored", "virtio-9p", fs_flush_ignored,
                  NULL);
     qos_add_test("fs/readdir/basic", "virtio-9p", fs_readdir, NULL);
+    qos_add_test("fs/readdir/split", "virtio-9p", fs_readdir_split, NULL);
 }
 
 libqos_init(register_virtio_9p_test);
-- 
2.20.1