gdkcairo: Bail if surface is in error

Don't try to paint onto an error surface. This happens for example when
gdk_cairo_set_source_pixbuf() is called with a pixbuf that is too big
for Cairo to handle.

Spotted by Christian Boxdörfer

2 files changed, 43 insertions, 2 deletions

diff --git a/testsuite/gdk/Makefile.am b/testsuite/gdk/Makefile.am
index 5b0d30f086..32b018a0c3 100644
--- a/testsuite/gdk/Makefile.am
+++ b/testsuite/gdk/Makefile.am
@@ -18,10 +18,11 @@ LDADD = 				\
 #TEST_PROGS              += check-gdk-cairo
 
 TEST_PROGS += 				\
-	rgba				\
-	encoding			\
+	cairo				\
 	display				\
+	encoding			\
 	keysyms				\
+	rgba				\
 	$(NULL)
 
 CLEANFILES = 			\
diff --git a/testsuite/gdk/cairo.c b/testsuite/gdk/cairo.c
new file mode 100644
index 0000000000..77be879c97
--- /dev/null
+++ b/testsuite/gdk/cairo.c
@@ -0,0 +1,40 @@
+#include <gdk/gdk.h>
+
+static void
+test_set_source_big_pixbuf (void)
+{
+  cairo_surface_t *surface;
+  GdkPixbuf *pixbuf;
+  cairo_t *cr;
+
+#define WAY_TOO_BIG 65540
+
+  /* Check that too big really is to big.
+   * If this check fails, somebody improved Cairo and this test is useless.
+   */
+  surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, WAY_TOO_BIG, 1);
+  g_assert_cmpint (cairo_surface_status (surface), !=, CAIRO_STATUS_SUCCESS);
+  cairo_surface_destroy (surface);
+
+  surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, 10, 10);
+  cr = cairo_create (surface);
+  pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, WAY_TOO_BIG, 1);
+
+  gdk_cairo_set_source_pixbuf (cr, pixbuf, 0, 0);
+  g_assert_cmpint (cairo_status (cr), !=, CAIRO_STATUS_SUCCESS);
+
+  g_object_unref (pixbuf);
+  cairo_destroy (cr);
+  cairo_surface_destroy (surface);
+}
+
+int
+main (int argc, char *argv[])
+{
+  g_test_init (&argc, &argv, NULL);
+  gdk_init (&argc, &argv);
+
+  g_test_add_func ("/drawing/set-source-big-pixbuf", test_set_source_big_pixbuf);
+
+  return g_test_run ();
+}