tests/9pfs: add local Tmkdir test

This test case uses the 9pfs 'local' driver to create a directory
and then checks if the expected directory was actually created
(as real directory) on host side.

This patch introduces a custom split() implementation, because
the test code requires non empty array elements as result. For
that reason g_strsplit() would not be a good alternative, as
it would require additional filter code for reshuffling the
array, and the resulting code would be even more complex than
this split() function.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <be342f236842272275f65dbe05587f0a5409ad77.1602182956.git.qemu_oss@crudebyte.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>

tests/qtest/virtio-9p-test.c

@@ -18,6 +18,62 @@
 #define QVIRTIO_9P_TIMEOUT_US (10 * 1000 * 1000)
 static QGuestAllocator *alloc;
 
+/*
+ * Used to auto generate new fids. Start with arbitrary high value to avoid
+ * collision with hard coded fids in basic test code.
+ */
+static uint32_t fid_generator = 1000;
+
+static uint32_t genfid(void)
+{
+    return fid_generator++;
+}
+
+/**
+ * Splits the @a in string by @a delim into individual (non empty) strings
+ * and outputs them to @a out. The output array @a out is NULL terminated.
+ *
+ * Output array @a out must be freed by calling split_free().
+ *
+ * @returns number of individual elements in output array @a out (without the
+ *          final NULL terminating element)
+ */
+static int split(const char *in, const char *delim, char ***out)
+{
+    int n = 0, i = 0;
+    char *tmp, *p;
+
+    tmp = g_strdup(in);
+    for (p = strtok(tmp, delim); p != NULL; p = strtok(NULL, delim)) {
+        if (strlen(p) > 0) {
+            ++n;
+        }
+    }
+    g_free(tmp);
+
+    *out = g_new0(char *, n + 1); /* last element NULL delimiter */
+
+    tmp = g_strdup(in);
+    for (p = strtok(tmp, delim); p != NULL; p = strtok(NULL, delim)) {
+        if (strlen(p) > 0) {
+            (*out)[i++] = g_strdup(p);
+        }
+    }
+    g_free(tmp);
+
+    return n;
+}
+
+static void split_free(char ***out)
+{
+    int i;
+    for (i = 0; (*out)[i]; ++i) {
+        g_free((*out)[i]);
+    }
+    g_free(*out);
+    *out = NULL;
+}
+
 static void pci_config(void *obj, void *data, QGuestAllocator *t_alloc)
 {
     QVirtio9P *v9p = obj;
@@ -201,6 +257,7 @@ static const char *rmessage_name(uint8_t id)
         id == P9_RWALK ? "RWALK" :
         id == P9_RLOPEN ? "RLOPEN" :
         id == P9_RWRITE ? "RWRITE" :
+        id == P9_RMKDIR ? "RMKDIR" :
         id == P9_RFLUSH ? "RFLUSH" :
         id == P9_RREADDIR ? "READDIR" :
         "<unknown>";
@@ -578,6 +635,39 @@ static bool fs_dirents_contain_name(struct V9fsDirent *e, const char* name)
     return false;
 }
 
+/* size[4] Tmkdir tag[2] dfid[4] name[s] mode[4] gid[4] */
+static P9Req *v9fs_tmkdir(QVirtio9P *v9p, uint32_t dfid, const char *name,
+                          uint32_t mode, uint32_t gid, uint16_t tag)
+{
+    P9Req *req;
+
+    uint32_t body_size = 4 + 4 + 4;
+    uint16_t string_size = v9fs_string_size(name);
+
+    g_assert_cmpint(body_size, <=, UINT32_MAX - string_size);
+    body_size += string_size;
+
+    req = v9fs_req_init(v9p, body_size, P9_TMKDIR, tag);
+    v9fs_uint32_write(req, dfid);
+    v9fs_string_write(req, name);
+    v9fs_uint32_write(req, mode);
+    v9fs_uint32_write(req, gid);
+    v9fs_req_send(req);
+    return req;
+}
+
+/* size[4] Rmkdir tag[2] qid[13] */
+static void v9fs_rmkdir(P9Req *req, v9fs_qid *qid)
+{
+    v9fs_req_recv(req, P9_RMKDIR);
+    if (qid) {
+        v9fs_memread(req, qid, 13);
+    } else {
+        v9fs_memskip(req, 13);
+    }
+    v9fs_req_free(req);
+}
+
 /* basic readdir test where reply fits into a single response message */
 static void fs_readdir(void *obj, void *data, QGuestAllocator *t_alloc)
 {
@@ -877,6 +967,30 @@ static void fs_flush_ignored(void *obj, void *data, QGuestAllocator *t_alloc)
     g_free(wnames[0]);
 }
 
+static void fs_mkdir(void *obj, void *data, QGuestAllocator *t_alloc,
+                     const char *path, const char *cname)
+{
+    QVirtio9P *v9p = obj;
+    alloc = t_alloc;
+    char **wnames;
+    char *const name = g_strdup(cname);
+    P9Req *req;
+    const uint32_t fid = genfid();
+
+    int nwnames = split(path, "/", &wnames);
+
+    req = v9fs_twalk(v9p, 0, fid, nwnames, wnames, 0);
+    v9fs_req_wait_for_reply(req, NULL);
+    v9fs_rwalk(req, NULL, NULL);
+
+    req = v9fs_tmkdir(v9p, fid, name, 0750, 0, 0);
+    v9fs_req_wait_for_reply(req, NULL);
+    v9fs_rmkdir(req, NULL);
+
+    g_free(name);
+    split_free(&wnames);
+}
+
 static void fs_readdir_split_128(void *obj, void *data,
                                  QGuestAllocator *t_alloc)
 {
@@ -895,6 +1009,30 @@ static void fs_readdir_split_512(void *obj, void *data,
     fs_readdir_split(obj, data, t_alloc, 512);
 }
 
+
+/* tests using the 9pfs 'local' fs driver */
+
+static void fs_create_dir(void *obj, void *data, QGuestAllocator *t_alloc)
+{
+    QVirtio9P *v9p = obj;
+    struct stat st;
+    char *root_path = virtio_9p_test_path("");
+    char *new_dir = virtio_9p_test_path("01");
+
+    g_assert(root_path != NULL);
+
+    fs_attach(v9p, NULL, t_alloc);
+    fs_mkdir(v9p, data, t_alloc, "/", "01");
+
+    /* check if created directory really exists now ... */
+    g_assert(stat(new_dir, &st) == 0);
+    /* ... and is actually a directory */
+    g_assert((st.st_mode & S_IFMT) == S_IFDIR);
+
+    g_free(new_dir);
+    g_free(root_path);
+}
+
 static void *assign_9p_local_driver(GString *cmd_line, void *arg)
 {
     virtio_9p_assign_local_driver(cmd_line, "security_model=mapped-xattr");
@@ -934,6 +1072,7 @@ static void register_virtio_9p_test(void)
     /* 9pfs test cases using the 'local' filesystem driver */
     opts.before = assign_9p_local_driver;
     qos_add_test("local/config", "virtio-9p", pci_config,  &opts);
+    qos_add_test("local/create_dir", "virtio-9p", fs_create_dir, &opts);
 }
 
 libqos_init(register_virtio_9p_test);