Our derivate work remains GPLv3+, since the original allowed it thanks
to its GPLv2+ license, but when we quote the original license we can't
(and shouldn't) change the fact that it was GPLv2+.
Apple's desktop operating system was formerly called "Mac OS X" and "OS X", but since 2016 it has been called "macOS" (starting with version 10.12).
Changing across all comments and documentation to use this current terminology, except in cases where the historical versions are explicitly referenced. No code changes are made; we should consider changing those in future PRs.
Engines should only have to call one set of functions and not decide between the two. In fact, the 'emulation' API was documented to just call the 'real CD' API.
Since Mac OS X Carbon/Cocoa API isn't stable (in that it's changed multiple times over the years). Maintaining two versions of the same code (one in some foreign language with overly long names) isn't very appealing to me.