CI for Linux, MinGW and macOS

[illwieckz]

CI for Linux, MinGW and macOS

[illwieckz]

The PR includes #46 to fix the macOS build:

• Remove obsolete sprintf calls #46

[illwieckz]

The codeql/appveyor changes were merged:

• azure: MacOS-11 -> MacOS-12 Daemon#1207

The snprintf fixes were merged:

• Remove obsolete sprintf calls #46

The MinGW fixes are now living in a separate PR:

• Improve MinGW compatibility #49

What is now remaining from this PR is the Azure Pipeline configuration.
I can't test it until Azure Pipeline is enabled for this repository.

[illwieckz]

I added some PNG, BMP and TGA test images from:

• https://github.com/UnvanquishedAssets/UnvanquishedTestAssets/tree/master/pkg/map-test-pngalpha_src.dpkdir/textures/test-pngalpha_custom_src
• https://gitlab.com/illwieckz/investigating-tga-orientation-in-imagemagick/-/tree/master/samples-default
• https://gitlab.com/illwieckz/investigating-tga-orientation-in-imagemagick/-/tree/master/samples

When running the Azure CI on a native platform (no cross-compilation), it runs crunch with them as input.

Currently, the test doesn't verify the output of crunch, but it already checks that the input format is not refused, and would catch this kind of error:

• crunch is known to not properly grok all png format variants #13

It also makes us able to run the test outside the CI and it makes me discover the raw TGA input format is not fully supported (horizontal orientation bit is ignored), I guess the error is in STB and then I would have to report them the error.

[slipher]

Seems kinda weird for a fork to use a logo belonging to the original version of the project

[illwieckz]

I had mixed feeling about it too. Especially all I wanted was an image to run crunch on, small (no need more) but with enough details to check for the output. I used a 64px unvanquished icon instead: it is small but detailed enough, and features alpha channel with some shadows, so it looks complex enough to me. It is not displayed, just stored in test/.

[illwieckz]

So, now Linux amd64, macOS amd64 and Windows/MSVC run the tests. The tests are only about running crunch on a set of images and only to check that crunch doesn't error out. We may do some checksums later but that's good enough for now and it's enough to validate the infrastructure is there.

[illwieckz]

For some unknown reason, when running in azure pipeline, test/test.py own print call is not displayed in azure pipeline output, same problem with either stdout or stderr output, I have no idea why. That's not a big problem and this may be investigated separately.