blob: 5e11237a8508df7945edb8e63644b7aa4c9bc12b [file] [log] [blame]
/*
* Copyright © 2006 Mozilla Corporation
*
* Permission to use, copy, modify, distribute, and sell this software
* and its documentation for any purpose is hereby granted without
* fee, provided that the above copyright notice appear in all copies
* and that both that copyright notice and this permission notice
* appear in supporting documentation, and that the name of
* Mozilla Corporation not be used in advertising or publicity pertaining to
* distribution of the software without specific, written prior
* permission. Mozilla Corporation makes no representations about the
* suitability of this software for any purpose. It is provided "as
* is" without express or implied warranty.
*
* MOZILLA CORPORATION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS, IN NO EVENT SHALL MOZILLA CORPORATION BE LIABLE FOR ANY SPECIAL,
* INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
* RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
* IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* Author: Vladimir Vukicevic <vladimir@pobox.com>
*/
#include "cairo-test.h"
/* This test was originally written to exercise a bug in pixman in
* which it would scribble all over memory when given a particular
* (and bogus) trapezoid. However, a recent change to
* _cairo_fixed_from_double changed the details of the bogus trapezoid
* (it overflows in a different way now), so the bug is being masked.
*
* According to Vladimir, (http://lists.freedesktop.org/archives/cairo/2006-November/008482.html):
*
* Before the change, the two trapezoids that were generated were:
*
* Trap[0]: T: 0x80000000 B: 0x80000003
* L: [(0x000a0000, 0x80000000) (0x00080000, 0x00080000)]
* R: [(0x01360000, 0x80000000) (0x01380000, 0x00080000)]
* Trap[1]: T: 0x80000003 B: 0x00080000
* L: [(0x000a0000, 0x80000000) (0x00080000, 0x00080000)]
* R: [(0x01360000, 0x80000000) (0x01380000, 0x00080000)]
*
* After the change, the L/R coordinates are identical for both traps, but
* the top and bottom change:
*
* Trap[0]: t: 0x80000000 b: 0xfda80003
* l: [(0x000a0000, 0x80000000) (0x00080000, 0x00080000)]
* r: [(0x01360000, 0x80000000) (0x01380000, 0x00080000)]
* Trap[1]: t: 0xfda80003 b: 0x00080000
* l: [(0x000a0000, 0x80000000) (0x00080000, 0x00080000)]
* r: [(0x01360000, 0x80000000) (0x01380000, 0x00080000)]
*
* I think the fix we want here is to rewrite this test to call
* directly into pixman with the trapezoid of interest, (which will
* require adding a new way to configure cairo for "testing" which
* will prevent the hiding of internal library symbols.
*/
static cairo_test_status_t
draw (cairo_t *cr, int width, int height)
{
cairo_set_source_rgb (cr, 1,1,1);
cairo_paint (cr);
cairo_set_source_rgb (cr, 0,0,0);
/* Note that without the clip, this doesn't crash... */
cairo_new_path (cr);
cairo_rectangle (cr, 0, 0, width, height);
cairo_clip (cr);
cairo_new_path (cr);
cairo_line_to (cr, 8.0, 8.0);
cairo_line_to (cr, 312.0, 8.0);
cairo_line_to (cr, 310.0, 31378756.2666666666);
cairo_line_to (cr, 10.0, 31378756.2666666666);
cairo_line_to (cr, 8.0, 8.0);
cairo_fill (cr);
return CAIRO_TEST_SUCCESS;
}
/* XFAIL: range overflow of fixed-point */
CAIRO_TEST (big_trap,
"Test oversize trapezoid with a clip region"
"\nTest needs to be adjusted to trigger the original bug",
"trap", /* keywords */
NULL, /* requirements */
100, 100,
NULL, draw)