boilerplate-xcb: Avoid leaks on error

Before this commit, running the test suite against a non-existing
display under valgrind resulted in:

$ ( cd test; DISPLAY=:2 CAIRO_TEST_TARGET=xcb valgrind --leak-check=full .libs/cairo-test-suite -f random-clip )
[...]
==47359== 64 bytes in 2 blocks are definitely lost in loss record 1 of 7
==47359==    at 0x483AB65: calloc (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
==47359==    by 0x18A272: cairo_boilerplate_xcalloc (cairo-boilerplate-system.c:65)
==47359==    by 0x18D652: _cairo_boilerplate_xcb_create_surface (cairo-boilerplate-xcb.c:269)
==47359==    by 0x12906F: cairo_test_for_target (cairo-test.c:819)
==47359==    by 0x12AAB5: _cairo_test_context_run_for_target (cairo-test.c:1555)
==47359==    by 0x126921: _cairo_test_runner_draw (cairo-test-runner.c:250)
==47359==    by 0x126921: main (cairo-test-runner.c:932)

This commit fixes that by freeing the allocated memory in the error
path.

Signed-off-by: Uli Schlachter <psychon@znc.in>

1 files changed, 7 insertions, 1 deletions

diff --git a/boilerplate/cairo-boilerplate-xcb.c b/boilerplate/cairo-boilerplate-xcb.c
index cc9b422e9..e301d1299 100644
--- a/boilerplate/cairo-boilerplate-xcb.c
+++ b/boilerplate/cairo-boilerplate-xcb.c
@@ -276,6 +276,7 @@ _cairo_boilerplate_xcb_create_surface (const char		 *name,
     xtc->c = c = xcb_connect(NULL,NULL);
     if (c == NULL || xcb_connection_has_error(c)) {
 	free (xtc);
+	free (info);
 	return NULL;
     }
 
@@ -309,12 +310,17 @@ _cairo_boilerplate_xcb_create_surface (const char		 *name,
     if (xcb_request_check (c, cookie) != NULL) {
 	xcb_disconnect (c);
 	free (xtc);
+	free (info);
 	return NULL;
     }
 
     info->formats = xcb_render_query_pict_formats_reply (c, formats_cookie, 0);
-    if (info->formats == NULL)
+    if (info->formats == NULL) {
+	xcb_disconnect (c);
+	free (xtc);
+	free (info);
 	return NULL;
+    }
 
     for (i = xcb_render_query_pict_formats_formats_iterator (info->formats);
 	 i.rem;