GUACAMOLE-377: Add protocol-level support for reporting remote frame statistics.

src/libguac/client.c

@@ -413,15 +413,19 @@ void* guac_client_for_user(guac_client* client, guac_user* user,
 }
 
 int guac_client_end_frame(guac_client* client) {
+    return guac_client_end_multiple_frames(client, 0);
+}
+
+int guac_client_end_multiple_frames(guac_client* client, int frames) {
 
     /* Update and send timestamp */
     client->last_sent_timestamp = guac_timestamp_current();
 
     /* Log received timestamp and calculated lag (at TRACE level only) */
     guac_client_log(client, GUAC_LOG_TRACE, "Server completed "
-            "frame %" PRIu64 "ms.", client->last_sent_timestamp);
+            "frame %" PRIu64 "ms (%i logical frames)", client->last_sent_timestamp, frames);
 
-    return guac_protocol_send_sync(client->socket, client->last_sent_timestamp);
+    return guac_protocol_send_sync(client->socket, client->last_sent_timestamp, frames);
 
 }
 

src/libguac/guacamole/client.h

@@ -509,18 +509,47 @@ void* guac_client_for_user(guac_client* client, guac_user* user,
         guac_user_callback* callback, void* data);
 
 /**
- * Marks the end of the current frame by sending a "sync" instruction to
- * all connected users. This instruction will contain the current timestamp.
- * The last_sent_timestamp member of guac_client will be updated accordingly.
+ * Marks the end of the current frame by sending a "sync" instruction to all
+ * connected users, where the number of input frames that were considered in
+ * creating this frame is either unknown or inapplicable. This instruction will
+ * contain the current timestamp. The last_sent_timestamp member of guac_client
+ * will be updated accordingly.
  *
  * If an error occurs sending the instruction, a non-zero value is
  * returned, and guac_error is set appropriately.
  *
- * @param client The guac_client which has finished a frame.
- * @return Zero on success, non-zero on error.
+ * @param client
+ *     The guac_client which has finished a frame.
+ *
+ * @return
+ *     Zero on success, non-zero on error.
  */
 int guac_client_end_frame(guac_client* client);
 
+/**
+ * Marks the end of the current frame by sending a "sync" instruction to all
+ * connected users, where that frame may combine or otherwise represent the
+ * changes of an arbitrary number of input frames. This instruction will
+ * contain the current timestamp, as well as the number of frames that were
+ * considered in creating that frame.  The last_sent_timestamp member of
+ * guac_client will be updated accordingly.
+ *
+ * If an error occurs sending the instruction, a non-zero value is
+ * returned, and guac_error is set appropriately.
+ *
+ * @param client
+ *     The guac_client which has finished a frame.
+ *
+ * @param frames
+ *     The number of distinct frames that were considered or combined when
+ *     generating the current frame, or zero if the boundaries of relevant
+ *     frames are unknown.
+ *
+ * @return
+ *     Zero on success, non-zero on error.
+ */
+int guac_client_end_multiple_frames(guac_client* client, int frames);
+
 /**
  * Initializes the given guac_client using the initialization routine provided
  * by the plugin corresponding to the named protocol. This will automatically

src/libguac/guacamole/protocol.h

@@ -363,11 +363,22 @@ int guac_protocol_send_select(guac_socket* socket, const char* protocol);
  * If an error occurs sending the instruction, a non-zero value is
  * returned, and guac_error is set appropriately.
  *
- * @param socket The guac_socket connection to use.
- * @param timestamp The current timestamp (in milliseconds).
- * @return Zero on success, non-zero on error.
+ * @param socket
+ *     The guac_socket connection to use.
+ *
+ * @param timestamp
+ *     The current timestamp (in milliseconds).
+ *
+ * @param frames
+ *     The number of distinct frames that were considered or combined when
+ *     generating the frame terminated by this instruction, or zero if the
+ *     boundaries of relevant frames are unknown.
+ *
+ * @return
+ *     Zero on success, non-zero on error.
  */
-int guac_protocol_send_sync(guac_socket* socket, guac_timestamp timestamp);
+int guac_protocol_send_sync(guac_socket* socket, guac_timestamp timestamp,
+        int frames);
 
 /* OBJECT INSTRUCTIONS */
 

src/libguac/protocol.c

@@ -1181,7 +1181,8 @@ int guac_protocol_send_start(guac_socket* socket, const guac_layer* layer,
 
 }
 
-int guac_protocol_send_sync(guac_socket* socket, guac_timestamp timestamp) {
+int guac_protocol_send_sync(guac_socket* socket, guac_timestamp timestamp,
+        int frames) {
 
     int ret_val;
 
@@ -1189,6 +1190,8 @@ int guac_protocol_send_sync(guac_socket* socket, guac_timestamp timestamp) {
     ret_val = 
            guac_socket_write_string(socket, "4.sync,")
         || __guac_socket_write_length_int(socket, timestamp)
+        || guac_socket_write_string(socket, ",")
+        || __guac_socket_write_length_int(socket, frames)
         || guac_socket_write_string(socket, ";");
 
     guac_socket_instruction_end(socket);