Post-release version bump to 0.25.1
Remove useless checks for NULL before freeing

This patch has been generated by the following Coccinelle semantic patch:

// Remove useless checks for NULL before freeing
//
// free (NULL) is a no-op, so there is no need to avoid it

@@
expression E;
@@
+ free (E);
+ E = NULL;
- if (unlikely (E != NULL)) {
-   free(E);
(
-   E = NULL;
|
-   E = 0;
)
   ...
- }

@@
expression E;
@@
+ free (E);
- if (unlikely (E != NULL)) {
-   free (E);
- }
test: Cleanup includes

All the tests are linked to libutil, hence it makes sence to always
include utils.h and reuse what it provides (config.h inclusion, access
to private pixman APIs, ARRAY_LENGTH, ...).
Use the ARRAY_LENGTH() macro when possible

This patch has been generated by the following Coccinelle semantic patch:

// Use the ARRAY_LENGTH() macro when possible
//
// Replace open-coded array length computations with the
// ARRAY_LENGTH() macro

@@
type T;
T[] E;
@@
- (sizeof(E)/sizeof(T))
+ ARRAY_LENGTH (E)
test: Reuse the ARRAY_LENGTH() macro

It is provided by utils.h, there is no need to redefine it.
demos: Consistently use G_N_ELEMENTS()

Instead of open-coding G_N_ELEMENTS(), just use it.
test: Produce autotools-looking report in the win32 build system

Tweak the commands used to run the tests on win32 to make the output
look mostly like that produced by the autotools test system.

In addition to this, make sure that the exit status of the test target
is success (0) if and only if no failure occurred.
Don't use non-POSIX test

test "$test_CFLAGS" == "" &&         \

may cause an error on some POSIX shells and uses a style which is not
consistent with the other tests in configure.ac

Fixes https://bugs.freedesktop.org/show_bug.cgi?id=42588 and
https://bugs.gentoo.org/show_bug.cgi?id=387087
Android Runtime Detection Support For ARM NEON

This patch adds runtime detection support for the ARM NEON fast paths
for code compiled with the Android NDK. This is the only code change
needed to enable the ARM NEON pixman fast paths for the ever growing
Android platform (200 million+ smartphones, tablets, etc.). Just make
sure to #define USE_ARM_NEON in your makefile.
region: Add pixman_region{,32}_clear() functions.

These functions simply reset the region to empty. They are equivalent
to

      pixman_region_fini (&region);
      pixman_region_init (&region);
Modify gradient-test to show a bug in NONE processing

This patch modifies demos/gradient-test to display a bug in gradients
with a repeat mode of NONE. With the current gradient code, the left
side will be a solid red (actually an extremely long fade from solid
red to transparent) instead of a sharp transition from red to green.
gradient-walker: For NONE repeats, when x < 0 or x > 1, set both colors to 0

ec7c9c2b6865b48b8bd14e4 introduced a bug where NONE gradients would be
misrendered, causing the area outside the gradient to be treated as a
(very) long fade to transparent.The problem was that a check for
positions outside the gradients were dropped in favor of relying on
the sentinels.

Aside from misrendering, this also caused a signed integer overflow
when the code would compute a stepper size based on MIN_INT32.

This patches fixes the issue by reinstating a check for these cases
and setting both the right and left colors to transparent black.
autogen.sh: Support GNOME Build API

http://people.gnome.org/~walters/docs/build-api.txt
pixman-image.c: Fix typo in pixman_image_set_transform()

A parenthesis was misplaced so that the size argument to memcmp() was
always 0. The bug is harmless except that the flags might be
unnecessarily recomputed in some cases.

A bug reporting this in Mozilla's fork was discovered here:

    https://bugzilla.mozilla.org/show_bug.cgi?id=710992
Fix some signed overflow bugs

In the macros for the PDF blend modes, two comp1_t variables are
multiplied together and then used as if the result were a
comp4_t. When comp1_t is a uint8_t, this is fine because they are
promoted to int, and the product of two uint8_ts fits in an
int. However, when comp1_t is uint16, the product does not necessarily
fit in an int, so casts are necessary.

Fix for bug 43906, reported by Siarhei Siamashka.
Add missing cast in _pixman_edge_multi_init()

nx and e->dy are both 32 bit quantities, so a cast is needed to make
sure their product is 64 bit before subtracting it from a 64 bit
quantity.
Fix a bunch of signed overflow issues

In pixman-fast-path.c: (1 << 31) - 1 causes a signed overflow, so
change to (1U << n) - 1.

In pixman-image.c: The check for whether m10 == -m01 will overflow
when -m01 == INT_MIN. Instead just check whether the variables are 1
and -1.

In pixman-utils.c: When the depth of the topmost channel is 0, we can
end up shifting by 32.

In blitters-test.c: Replicating the mask would end up shifting more
than 32.

In region-contains-test.c: Computing the average of two large integers
could overflow. Instead add half the difference between them to the
first integer.

In stress-test.c: Masking the value in fake_reader() would sometimes
shift by 32. Instead just use the most significant bits instead of
the least significant.

All these issues were found by the IOC tool:

    http://embed.cs.utah.edu/ioc/
In MUL_UNc() cast to comp2_t

Otherwise, when comp1_t is 16 bits wide, we can end up with a signed
integer overflow.
Reject trapezoids where top (botttom) is above (below) the edges

When a trapezoid has a top/bottom that is above/below the left/right
edges, degenerate trapezoids become possible. For example the edge
could be very short and close to horizontal. If the bottom edge is far
below the bottom point of such a short edge, the result is that the
lower right corner of the trapezoid will be extremely far to the left.

This kind of trapezoid causes overflows in the rasterization code, so
change pixman_trapezoid_valid() to reject them.
Fix rounding for DIV_UNc()

We need to compute floor (a/b * 255 + 0.5), not floor (a / b * 255),
so add b/2 to the numerator in the DIV_UNc() macro.