GUACAMOLE-629: Add support for sending "argv" instructions from server to client.

src/libguac/guacamole/protocol.h

@@ -932,6 +932,31 @@ int guac_protocol_send_size(guac_socket* socket, const guac_layer* layer,
 
 /* TEXT INSTRUCTIONS */
 
+/**
+ * Sends an argv instruction over the given guac_socket connection.
+ *
+ * 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 to send the connection parameter
+ *     value.
+ *
+ * @param stream
+ *     The stream to use to send the connection parameter value.
+ *
+ * @param mimetype
+ *     The mimetype of the connection parameter value being sent.
+ *
+ * @param name
+ *     The name of the connection parameter whose current value is being sent.
+ *
+ * @return
+ *     Zero on success, non-zero on error.
+ */
+int guac_protocol_send_argv(guac_socket* socket, guac_stream* stream,
+        const char* mimetype, const char* name);
+
 /**
  * Sends a clipboard instruction over the given guac_socket connection.
  *

src/libguac/protocol.c

@@ -125,6 +125,26 @@ int guac_protocol_send_args(guac_socket* socket, const char** args) {
 
 }
 
+int guac_protocol_send_argv(guac_socket* socket, guac_stream* stream,
+        const char* mimetype, const char* name) {
+
+    int ret_val;
+
+    guac_socket_instruction_begin(socket);
+    ret_val =
+           guac_socket_write_string(socket, "4.argv,")
+        || __guac_socket_write_length_int(socket, stream->index)
+        || guac_socket_write_string(socket, ",")
+        || __guac_socket_write_length_string(socket, mimetype)
+        || guac_socket_write_string(socket, ",")
+        || __guac_socket_write_length_string(socket, name)
+        || guac_socket_write_string(socket, ";");
+
+    guac_socket_instruction_end(socket);
+    return ret_val;
+
+}
+
 int guac_protocol_send_arc(guac_socket* socket, const guac_layer* layer,
         int x, int y, int radius, double startAngle, double endAngle,
         int negative) {