utils: implement g_cancellable_new_with_timeout

lib/utils/mu-utils-file.cc

@@ -178,6 +178,55 @@ Mu::runtime_path(Mu::RuntimePath path, const std::string& muhome)
 	}
 }
 
+static gpointer
+cancel_wait(gpointer data)
+{
+	guint timeout, deadline;
+	GCancellable *cancel;
+
+	cancel	 = (GCancellable*)data;
+	timeout	 = GPOINTER_TO_UINT(g_object_get_data(G_OBJECT(cancel), "timeout"));
+	deadline = g_get_monotonic_time() + 1000 * timeout;
+
+	while (g_get_monotonic_time() < deadline && !g_cancellable_is_cancelled(cancel)) {
+		g_usleep(50 * 1000); /* 50 ms */
+		g_thread_yield();
+	}
+
+	g_cancellable_cancel(cancel);
+
+	return NULL;
+}
+
+static void
+cancel_wait_free(gpointer data)
+{
+	GThread *thread;
+	GCancellable *cancel;
+
+	cancel	 = (GCancellable*)data;
+	thread   = (GThread*)g_object_get_data(G_OBJECT(cancel), "thread");
+
+	g_cancellable_cancel(cancel);
+	g_thread_join(thread);
+}
+
+GCancellable*
+Mu::g_cancellable_new_with_timeout(guint timeout)
+{
+	GCancellable *cancel;
+
+	cancel = g_cancellable_new();
+
+	g_object_set_data(G_OBJECT(cancel), "timeout", GUINT_TO_POINTER(timeout));
+	g_object_set_data(G_OBJECT(cancel), "thread",
+			  g_thread_new("cancel-wait", cancel_wait, cancel));
+	g_object_set_data_full(G_OBJECT(cancel), "cancel", cancel, cancel_wait_free);
+
+
+	return cancel;
+}
+
 
 #ifdef BUILD_TESTS
 

lib/utils/mu-utils-file.hh

@@ -24,6 +24,7 @@
 #include <cinttypes>
 #include <sys/stat.h>
 
+#include <gio/gio.h>
 #include <utils/mu-option.hh>
 #include <utils/mu-regex.hh>
 
@@ -157,6 +158,17 @@ std::string join_paths(S&& s, Args...args) {
 }
 
 
+/**
+ * Like g_cancellable_new(), but automatically cancels itself
+ * after timeout
+ *
+ * @param timeout timeout in millisecs
+ *
+ * @return A GCancellable* instances; free with g_object_unref() when
+ * no longer needed.
+ */
+GCancellable* g_cancellable_new_with_timeout(guint timeout);
+
 } // namespace Mu
 
 #endif /* MU_UTILS_FILE_HH__ */