From e13c646465fee03c813251fcd1bbf258f359055d Mon Sep 17 00:00:00 2001
From: Christoph Reiter <creiter@src.gnome.org>
Date: Tue, 5 Mar 2019 16:44:16 +0100
Subject: [PATCH] gcancellable: add back lost NULL check in
 g_cancellable_cancel()

Commit f975858e86 removed the NULL check in g_cancellable_cancel() by
accident which makes it crash when called with NULL.

Add the check back and add a test so this doesn't happen again.

Fixes #1710
---
 gio/gcancellable.c      | 2 +-
 gio/tests/cancellable.c | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/gio/gcancellable.c b/gio/gcancellable.c
index 32605ce02..31e990f3c 100644
--- a/gio/gcancellable.c
+++ b/gio/gcancellable.c
@@ -484,7 +484,7 @@ g_cancellable_cancel (GCancellable *cancellable)
 {
   GCancellablePrivate *priv;
 
-  if (g_cancellable_is_cancelled (cancellable))
+  if (cancellable == NULL || g_cancellable_is_cancelled (cancellable))
     return;
 
   priv = cancellable->priv;
diff --git a/gio/tests/cancellable.c b/gio/tests/cancellable.c
index e06650ed8..044628228 100644
--- a/gio/tests/cancellable.c
+++ b/gio/tests/cancellable.c
@@ -216,12 +216,19 @@ test_cancel_multiple_concurrent (void)
   g_main_loop_unref (loop);
 }
 
+static void
+test_cancel_null (void)
+{
+  g_cancellable_cancel (NULL);
+}
+
 int
 main (int argc, char *argv[])
 {
   g_test_init (&argc, &argv, NULL);
 
   g_test_add_func ("/cancellable/multiple-concurrent", test_cancel_multiple_concurrent);
+  g_test_add_func ("/cancellable/null", test_cancel_null);
 
   return g_test_run ();
 }