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+/*
+ * 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)