Separate main logic into a library with C FFI interface

[namazso]

No description provided.

[namazso]

@DoorsDev @OrthodoxWindows @boromyr @EnhancedJax @AlNexus @My3hab

This is now in a seemingly functional state (although not extensively tested yet). ThemeTool was also ported to this newly exposed API, so you can implement anything that ThemeTool can do.

You can find headers in the public folder, it's a pure C API, so you can invoke it from whatever language you wish.

CI has x86 builds of ThemeDll.dll in the Everything artifact (this can install to any of x86/x64/ARM64), if you need a different architecture build it yourself. The dll ships and registers (with secureuxtheme_set_dll_for_arch) the SecureUxTheme.dll builds, so you don't have to bother with that.

Feel free to comment if you'd like some more functionality exposed.

[Spiritreader]

Feel free to comment if you'd like some more functionality exposed.

Is it possible to include

/**
 * @brief Release (free) a theme pointer.
 * @param theme Opaque theme pointer
 */
void themetool_theme_release(ITheme* theme);

mentioned in the public/themetool.h file?

I see it's declared there but I get an unable to find an entry point error message when calling it.
I looked at my self-compiled x64 ThemeDlls and as well as the Win32 one I downloaded from Github Actions CI via a dependency walker.

The function seems to be missing

[namazso]

I seem to have missed exporting it, good catch!
And glad you got your builds working.