[cairo-commit] src/cairo-traps-compositor.c

[Chris Wilson]

 src/cairo-traps-compositor.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

New commits:
commit 113ec6bf0c8ed1ff12293d1ed2a2de9bd5b9904b
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Sun Apr 8 17:58:13 2012 +0100

    traps: Clip the trapezoid extents against the clip extents
    
    Just in case the clip polygon turns out to be much larger than the
    operation extents (silly us for not reducing it correctly) and lead to
    catastrophe, such as:
    
    Program received signal SIGSEGV, Segmentation fault.
    pixman_fill_sse2 (bits=<optimized out>, stride=4, bpp=8, x=0, y=0,
    width=3, height=-34811, data=0) at pixman-sse2.c:3369
    3369		    *(uint16_t *)d = data;
    
    Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

diff --git a/src/cairo-traps-compositor.c b/src/cairo-traps-compositor.c
index 284a0be..c49e208 100644
--- a/src/cairo-traps-compositor.c
+++ b/src/cairo-traps-compositor.c
@@ -218,8 +218,13 @@ combine_clip_as_traps (const cairo_traps_compositor_t *compositor,
     _cairo_traps_fini (&traps);
     cairo_surface_destroy (src);
 
-    if (status == CAIRO_INT_STATUS_SUCCESS &&
-	(fixup.width < extents->width || fixup.height < extents->height)) {
+    if (unlikely (status))
+	return status;
+
+    if (! _cairo_rectangle_intersect (&fixup, extents))
+	return CAIRO_STATUS_SUCCESS;
+
+    if (fixup.width < extents->width || fixup.height < extents->height) {
 	cairo_boxes_t clear;
 
 	_cairo_boxes_init (&clear);