In c2cb303d33, return_if_fail()s were added to
prevent the trapezoid rasterizers from being called with non-alpha
formats. However, stress-test actually does call the rasterizers with
non-alpha formats, but because _pixman_log_error() is disabled in
versions with an odd minor number, the errors never materialized.
Fix this by changing the argument to random format to an enum of three
values DONT_CARE, PREFER_ALPHA, or REQUIRE_ALPHA, and then in the
switch that calls the trapezoid rasterizers, pass the appropriate
value for the function in question.
The entry points add_trapezoids(), rasterize_trapezoid() and
composite_trapezoid() are exercised with random trapezoids.
This uncovers crashes with stress-test seeds 0x17ee and 0x313c.
This test runs the new floating point combiners on random input with
divide-by-zero exceptions turned on.
With the floating point combiners the only thing we guarantee is that
divide-by-zero exceptions are not generated, so change
enable_fp_exceptions() to only enable those, and rename accordingly.
The rectangles in the clip region set in set_general_properties()
would sometimes overflow, which would lead to messages like these:
*** BUG ***
In pixman_region32_union_rect: Invalid rectangle passed
Set a breakpoint on '_pixman_log_error' to debug
when the micro version number of pixman is even.
Fix this by detecting the overflow and clamping such that the x2/y2
coordinates are less than INT32_MAX.
Composite checks random combinations of operations that now also have
sRGB sources, masks and destinations, and stress-test validates the
read/write primitives.
stress-test current almost never composites anything because the clip
rectangles and transformations are such that either
_pixman_compute_composite_region32() or analyze_extent() will return
FALSE.
Fix this by:
- making log_rand() return smaller numbers so that the clip rectangles
are more likely to be within the destination image
- adding rand_x() and rand_y() functions that pick positions within an
image and using them for positioning alpha maps and source/mask
positions.
- making it less likely that clip regions are used in general
These changes make the test take longer, so speed it up a little by
making most images smaller and by reducing the maximum convolution
filter from 17x19 to 3x4.
With these changes, stress-test reveals a crash in iteration 0xd39
where fast_composite_tiled_repeat() creates an indexed image without a
palette.
Unsigned loop variables are only supported since version 3.0
of OpenMP specification. Changing loop variables to use int32_t
type fixes pixman build problems with path64 compiler.
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/
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, ...).
This patch makes so that composite and stress-test will start from a
random seed if the PIXMAN_RANDOMIZE_TESTS environment variable is
set. Running the test suite in this mode is useful to get more test
coverage.
Also, in stress-test.c make it so that setting the initial seed causes
threads to be turned off. This makes it much easier to see when
something fails.
MSVC does not notice non-returning functions (abort() / assert(0))
and warns about paths which end with them in non-void functions:
c:\cygwin\home\ranma42\code\fdo\pixman\test\fetch-test.c(114) :
warning C4715: 'reader' : not all control paths return a value
c:\cygwin\home\ranma42\code\fdo\pixman\test\stress-test.c(133) :
warning C4715: 'real_reader' : not all control paths return a value
c:\cygwin\home\ranma42\code\fdo\pixman\test\composite.c(431) :
warning C4715: 'calc_op' : not all control paths return a value
These warnings can be silenced by adding a return after the
termination call.
This test program tries to use as many rarely-used features as
possible, including alpha maps, accessor functions, oddly-sized
images, strange transformations, conical gradients, etc.
The hope is to provoke crashes or irregular behavior in pixman.