[libsoup/websockets-fixes-2.64: 3/19] WebSockets: allow to send empty binary data

[Claudio Saavedra <csaavedra src gnome org>]

commit c949ff53edacf1cc0337a438f8315cc24a414a1d
Author: Carlos Garcia Campos <cgarcia igalia com>
Date:   Tue Jun 18 11:20:18 2019 +0200

    WebSockets: allow to send empty binary data
    
    Passing data=NULL and length=0 which is consistent with g_bytes_new().

 libsoup/soup-websocket-connection.c |  6 ++--
 tests/websocket-test.c              | 55 +++++++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+), 3 deletions(-)
---
diff --git a/libsoup/soup-websocket-connection.c b/libsoup/soup-websocket-connection.c
index 35eee6a6..899e0651 100644
--- a/libsoup/soup-websocket-connection.c
+++ b/libsoup/soup-websocket-connection.c
@@ -1722,10 +1722,10 @@ soup_websocket_connection_send_text (SoupWebsocketConnection *self,
 /**
  * soup_websocket_connection_send_binary:
  * @self: the WebSocket
- * @data: (array length=length) (element-type guint8): the message contents
+ * @data: (array length=length) (element-type guint8) (nullable): the message contents
  * @length: the length of @data
  *
- * Send a binary message to the peer.
+ * Send a binary message to the peer. If @length is 0, @data may be %NULL.
  *
  * The message is queued to be sent and will be sent when the main loop
  * is run.
@@ -1739,7 +1739,7 @@ soup_websocket_connection_send_binary (SoupWebsocketConnection *self,
 {
        g_return_if_fail (SOUP_IS_WEBSOCKET_CONNECTION (self));
        g_return_if_fail (soup_websocket_connection_get_state (self) == SOUP_WEBSOCKET_STATE_OPEN);
-       g_return_if_fail (data != NULL);
+       g_return_if_fail (data != NULL || length == 0);
 
        send_message (self, SOUP_WEBSOCKET_QUEUE_NORMAL, 0x02, data, length);
 }
diff --git a/tests/websocket-test.c b/tests/websocket-test.c
index 2347ed5c..4015a96d 100644
--- a/tests/websocket-test.c
+++ b/tests/websocket-test.c
@@ -291,6 +291,21 @@ on_text_message (SoupWebsocketConnection *ws,
        *receive = g_bytes_ref (message);
 }
 
+static void
+on_binary_message (SoupWebsocketConnection *ws,
+                  SoupWebsocketDataType type,
+                  GBytes *message,
+                  gpointer user_data)
+{
+       GBytes **receive = user_data;
+
+       g_assert_cmpint (type, ==, SOUP_WEBSOCKET_DATA_BINARY);
+       g_assert (*receive == NULL);
+       g_assert (message != NULL);
+
+       *receive = g_bytes_ref (message);
+}
+
 static void
 on_close_set_flag (SoupWebsocketConnection *ws,
                    gpointer user_data)
@@ -444,6 +459,37 @@ test_send_big_packets (Test *test,
        g_bytes_unref (received);
 }
 
+static void
+test_send_empty_packets (Test *test,
+                        gconstpointer data)
+{
+       GBytes *received = NULL;
+       gulong id;
+
+       id = g_signal_connect (test->client, "message", G_CALLBACK (on_text_message), &received);
+
+       soup_websocket_connection_send_text (test->server, "\0");
+       WAIT_UNTIL (received != NULL);
+       g_assert_nonnull (g_bytes_get_data (received, NULL));
+       g_assert_cmpuint (((char *) g_bytes_get_data (received, NULL))[0], ==, '\0');
+       g_assert_cmpuint (g_bytes_get_size (received), ==, 0);
+       g_bytes_unref (received);
+       received = NULL;
+       g_signal_handler_disconnect (test->client, id);
+
+       id = g_signal_connect (test->client, "message", G_CALLBACK (on_binary_message), &received);
+
+       soup_websocket_connection_send_binary (test->server, NULL, 0);
+       WAIT_UNTIL (received != NULL);
+       /* We always include at least a null character */
+       g_assert_nonnull (g_bytes_get_data (received, NULL));
+       g_assert_cmpuint (((char *) g_bytes_get_data (received, NULL))[0], ==, '\0');
+       g_assert_cmpuint (g_bytes_get_size (received), ==, 0);
+       g_bytes_unref (received);
+       received = NULL;
+       g_signal_handler_disconnect (test->client, id);
+}
+
 static void
 test_send_bad_data (Test *test,
                     gconstpointer unused)
@@ -935,6 +981,15 @@ main (int argc,
                    test_send_big_packets,
                    teardown_soup_connection);
 
+       g_test_add ("/websocket/direct/send-empty-packets", Test, NULL,
+                   setup_direct_connection,
+                   test_send_empty_packets,
+                   teardown_direct_connection);
+       g_test_add ("/websocket/soup/send-empty-packets", Test, NULL,
+                   setup_soup_connection,
+                   test_send_empty_packets,
+                   teardown_soup_connection);
+
        g_test_add ("/websocket/direct/send-bad-data", Test, NULL,
                    setup_direct_connection,
                    test_send_bad_data,