qtest: add a test to test redirector status change

This patch adds a qtest to test the status change of
filter-redirector. Two subtests were added:

- test_redirector_status: tests dynamic on/off switching at runtime
  using qom-set QMP command

- test_redirector_init_status_off: tests creating filter-redirector
  with status=off from the start via command line

Both tests verify that:

1. When status is off, data from indev chardev is not received
2. When status is switched to on, data is received correctly

Reviewed-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

tests/qtest/test-filter-redirector.c

@@ -196,10 +196,202 @@ static void test_redirector_rx(void)
     qtest_quit(qts);
 }
 
+/*
+ * Test filter-redirector status on/off switching.
+ *
+ * This test verifies that:
+ * 1. When status is set to "off", the filter stops receiving data from indev
+ * 2. When status is set back to "on", the filter resumes receiving data
+ */
+static void test_redirector_status(void)
+{
+    int backend_sock[2], send_sock;
+    uint32_t ret = 0, len = 0;
+    char send_buf[] = "Hello!!";
+    char sock_path0[] = "filter-redirector0.XXXXXX";
+    char *recv_buf;
+    uint32_t size = sizeof(send_buf);
+    size = htonl(size);
+    QTestState *qts;
+    struct timeval tv;
+    fd_set rfds;
+
+    ret = socketpair(PF_UNIX, SOCK_STREAM, 0, backend_sock);
+    g_assert_cmpint(ret, !=, -1);
+
+    ret = mkstemp(sock_path0);
+    g_assert_cmpint(ret, !=, -1);
+
+    /*
+     * Setup a simple rx path:
+     * chardev (sock_path0) -> filter-redirector -> socket backend
+     */
+    qts = qtest_initf(
+        "-nic socket,id=qtest-bn0,fd=%d "
+        "-chardev socket,id=redirector0,path=%s,server=on,wait=off "
+        "-object filter-redirector,id=qtest-f0,netdev=qtest-bn0,"
+        "queue=rx,indev=redirector0 ",
+        backend_sock[1], sock_path0);
+
+    send_sock = unix_connect(sock_path0, NULL);
+    g_assert_cmpint(send_sock, !=, -1);
+
+    /* send a qmp command to guarantee that 'connected' is setting to true. */
+    qtest_qmp_assert_success(qts, "{ 'execute' : 'query-status'}");
+
+    struct iovec iov[] = {
+        {
+            .iov_base = &size,
+            .iov_len = sizeof(size),
+        }, {
+            .iov_base = send_buf,
+            .iov_len = sizeof(send_buf),
+        },
+    };
+
+    /*
+     * Test 1: Set status to "off" and verify data is not received
+     */
+    qtest_qmp_assert_success(qts,
+        "{ 'execute': 'qom-set', 'arguments': "
+        "{ 'path': '/objects/qtest-f0', 'property': 'status', 'value': 'off' }}");
+
+    ret = iov_send(send_sock, iov, 2, 0, sizeof(size) + sizeof(send_buf));
+    g_assert_cmpint(ret, ==, sizeof(send_buf) + sizeof(size));
+
+    /*
+     * Use select with timeout to check if data arrives.
+     * When status is off, no data should arrive.
+     */
+    FD_ZERO(&rfds);
+    FD_SET(backend_sock[0], &rfds);
+    tv.tv_sec = 0;
+    tv.tv_usec = 500000;  /* 500ms timeout */
+    ret = select(backend_sock[0] + 1, &rfds, NULL, NULL, &tv);
+    g_assert_cmpint(ret, ==, 0);  /* Should timeout, no data */
+
+    /*
+     * Test 2: Set status back to "on" and verify data is received
+     */
+    qtest_qmp_assert_success(qts,
+        "{ 'execute': 'qom-set', 'arguments': "
+        "{ 'path': '/objects/qtest-f0', 'property': 'status', 'value': 'on' }}");
+
+    ret = iov_send(send_sock, iov, 2, 0, sizeof(size) + sizeof(send_buf));
+    g_assert_cmpint(ret, ==, sizeof(send_buf) + sizeof(size));
+
+    ret = recv(backend_sock[0], &len, sizeof(len), 0);
+    g_assert_cmpint(ret, ==, sizeof(len));
+    len = ntohl(len);
+
+    g_assert_cmpint(len, ==, sizeof(send_buf));
+    recv_buf = g_malloc(len);
+    ret = recv(backend_sock[0], recv_buf, len, 0);
+    g_assert_cmpint(ret, ==, len);
+    g_assert_cmpstr(recv_buf, ==, send_buf);
+
+    g_free(recv_buf);
+    close(send_sock);
+    unlink(sock_path0);
+    qtest_quit(qts);
+}
+
+/*
+ * Test filter-redirector created with status=off.
+ *
+ * This test verifies that when a filter-redirector is created with
+ * status=off, it does not receive data until status is set to on.
+ */
+static void test_redirector_init_status_off(void)
+{
+    int backend_sock[2], send_sock;
+    uint32_t ret = 0, len = 0;
+    char send_buf[] = "Hello!!";
+    char sock_path0[] = "filter-redirector0.XXXXXX";
+    char *recv_buf;
+    uint32_t size = sizeof(send_buf);
+    size = htonl(size);
+    QTestState *qts;
+    struct timeval tv;
+    fd_set rfds;
+
+    ret = socketpair(PF_UNIX, SOCK_STREAM, 0, backend_sock);
+    g_assert_cmpint(ret, !=, -1);
+
+    ret = mkstemp(sock_path0);
+    g_assert_cmpint(ret, !=, -1);
+
+    /*
+     * Create filter-redirector with status=off from the start
+     */
+    qts = qtest_initf(
+        "-nic socket,id=qtest-bn0,fd=%d "
+        "-chardev socket,id=redirector0,path=%s,server=on,wait=off "
+        "-object filter-redirector,id=qtest-f0,netdev=qtest-bn0,"
+        "queue=rx,indev=redirector0,status=off ",
+        backend_sock[1], sock_path0);
+
+    send_sock = unix_connect(sock_path0, NULL);
+    g_assert_cmpint(send_sock, !=, -1);
+
+    qtest_qmp_assert_success(qts, "{ 'execute' : 'query-status'}");
+
+    struct iovec iov[] = {
+        {
+            .iov_base = &size,
+            .iov_len = sizeof(size),
+        }, {
+            .iov_base = send_buf,
+            .iov_len = sizeof(send_buf),
+        },
+    };
+
+    /*
+     * Test 1: Filter was created with status=off, data should not be received
+     */
+    ret = iov_send(send_sock, iov, 2, 0, sizeof(size) + sizeof(send_buf));
+    g_assert_cmpint(ret, ==, sizeof(send_buf) + sizeof(size));
+
+    FD_ZERO(&rfds);
+    FD_SET(backend_sock[0], &rfds);
+    tv.tv_sec = 0;
+    tv.tv_usec = 500000;
+    ret = select(backend_sock[0] + 1, &rfds, NULL, NULL, &tv);
+    g_assert_cmpint(ret, ==, 0);  /* Should timeout, no data */
+
+    /*
+     * Test 2: Set status to "on" and verify data is received
+     */
+    qtest_qmp_assert_success(qts,
+        "{ 'execute': 'qom-set', 'arguments': "
+        "{ 'path': '/objects/qtest-f0', 'property': 'status', 'value': 'on' }}");
+
+    ret = iov_send(send_sock, iov, 2, 0, sizeof(size) + sizeof(send_buf));
+    g_assert_cmpint(ret, ==, sizeof(send_buf) + sizeof(size));
+
+    ret = recv(backend_sock[0], &len, sizeof(len), 0);
+    g_assert_cmpint(ret, ==, sizeof(len));
+    len = ntohl(len);
+
+    g_assert_cmpint(len, ==, sizeof(send_buf));
+    recv_buf = g_malloc(len);
+    ret = recv(backend_sock[0], recv_buf, len, 0);
+    g_assert_cmpint(ret, ==, len);
+    g_assert_cmpstr(recv_buf, ==, send_buf);
+
+    g_free(recv_buf);
+    close(send_sock);
+    unlink(sock_path0);
+    qtest_quit(qts);
+}
+
 int main(int argc, char **argv)
 {
     g_test_init(&argc, &argv, NULL);
     qtest_add_func("/netfilter/redirector_tx", test_redirector_tx);
     qtest_add_func("/netfilter/redirector_rx", test_redirector_rx);
+    qtest_add_func("/netfilter/redirector_status", test_redirector_status);
+    qtest_add_func("/netfilter/redirector_init_status_off",
+                   test_redirector_init_status_off);
     return g_test_run();
 }