[3/3] tests: add /vhost-user/flags-mismatch test

diff --git a/tests/vhost-user-test.c b/tests/vhost-user-test.c
index ffdd398..a39846e 100644
--- a/tests/vhost-user-test.c
+++ b/tests/vhost-user-test.c
@@ -130,6 +130,13 @@  static VhostUserMsg m __attribute__ ((unused));
 #define VHOST_USER_VERSION    (0x1)
 /*****************************************************************************/
 
+enum {
+    TEST_FLAGS_OK,
+    TEST_FLAGS_DISCONNECT,
+    TEST_FLAGS_BAD,
+    TEST_FLAGS_END,
+};
+
 typedef struct TestServer {
     gchar *socket_path;
     gchar *mig_path;
@@ -143,6 +150,7 @@  typedef struct TestServer {
     int log_fd;
     uint64_t rings;
     bool test_fail;
+    int test_flags;
     int queues;
 } TestServer;
 
@@ -292,6 +300,10 @@  static void chr_read(void *opaque, const uint8_t *buf, int size)
         if (s->queues > 1) {
             msg.payload.u64 |= 0x1ULL << VIRTIO_NET_F_MQ;
         }
+        if (s->test_flags >= TEST_FLAGS_BAD) {
+            msg.payload.u64 = 0;
+            s->test_flags = TEST_FLAGS_END;
+        }
         p = (uint8_t *) &msg;
         qemu_chr_fe_write_all(chr, p, VHOST_USER_HDR_SIZE + msg.size);
         break;
@@ -299,6 +311,10 @@  static void chr_read(void *opaque, const uint8_t *buf, int size)
     case VHOST_USER_SET_FEATURES:
 	g_assert_cmpint(msg.payload.u64 & (0x1ULL << VHOST_USER_F_PROTOCOL_FEATURES),
 			!=, 0ULL);
+        if (s->test_flags == TEST_FLAGS_DISCONNECT) {
+            qemu_chr_disconnect(chr);
+            s->test_flags = TEST_FLAGS_BAD;
+        }
         break;
 
     case VHOST_USER_GET_PROTOCOL_FEATURES:
@@ -424,6 +440,16 @@  static TestServer *test_server_new(const gchar *name)
     return server;
 }
 
+static void chr_event(void *opaque, int event)
+{
+    TestServer *s = opaque;
+
+    if (s->test_flags == TEST_FLAGS_END &&
+        event == CHR_EVENT_CLOSED) {
+        s->test_flags = TEST_FLAGS_OK;
+    }
+}
+
 static void test_server_create_chr(TestServer *server, const gchar *opt)
 {
     gchar *chr_path;
@@ -432,7 +458,8 @@  static void test_server_create_chr(TestServer *server, const gchar *opt)
     server->chr = qemu_chr_new(server->chr_name, chr_path, NULL);
     g_free(chr_path);
 
-    qemu_chr_add_handlers(server->chr, chr_can_read, chr_read, NULL, server);
+    qemu_chr_add_handlers(server->chr, chr_can_read, chr_read,
+                          chr_event, server);
 }
 
 static void test_server_listen(TestServer *server)
@@ -774,6 +801,34 @@  static void test_connect_fail(void)
     g_free(path);
 }
 
+static void test_flags_mismatch_subprocess(void)
+{
+    TestServer *s = test_server_new("flags-mismatch");
+    char *cmd;
+
+    s->test_flags = TEST_FLAGS_DISCONNECT;
+    g_thread_new("connect", connect_thread, s);
+    cmd = GET_QEMU_CMDE(s, 2, ",server", "");
+    qtest_start(cmd);
+    g_free(cmd);
+
+    init_virtio_dev(s);
+    wait_for_fds(s);
+    wait_for_rings_started(s, 2);
+
+    qtest_end();
+    test_server_free(s);
+}
+
+static void test_flags_mismatch(void)
+{
+    gchar *path = g_strdup_printf("/%s/vhost-user/flags-mismatch/subprocess",
+                                  qtest_get_arch());
+    g_test_trap_subprocess(path, 0, 0);
+    g_test_trap_assert_passed();
+    g_free(path);
+}
+
 #endif
 
 static QVirtioPCIDevice *virtio_net_pci_init(QPCIBus *bus, int slot)
@@ -908,6 +963,9 @@  int main(int argc, char **argv)
     qtest_add_func("/vhost-user/connect-fail/subprocess",
                    test_connect_fail_subprocess);
     qtest_add_func("/vhost-user/connect-fail", test_connect_fail);
+    qtest_add_func("/vhost-user/flags-mismatch/subprocess",
+                   test_flags_mismatch_subprocess);
+    qtest_add_func("/vhost-user/flags-mismatch", test_flags_mismatch);
 #endif
 
     ret = g_test_run();