add macOS mount flags

[pwang7]

#1688 add macOS mount flags according to Apple sys/mount.h

Closes #1688

[rust-highfive]

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[JohnTitor]

Since I just added bunch of flags, do these flags have to be used?

Because MNT_FORCE is already defined in:

libc/src/unix/bsd/mod.rs

Line 326 in 8ba9ba2

pub const MNT_FORCE: ::c_int = 0x80000;

You can just remove that const from your defined.
Hm, we may be able to move the consts to bsd/mod.rs (I thought they were defined as c_ulonglong)... But it's out of scope, I can follow-up later if you don't.

And you should comment on this PR, not the issue so that we don't have to come and go :)

[JohnTitor]

Also, you should resolve style failure.

[pwang7]

Should I move these flags to libc/src/unix/bsd/mod.rs?

[JohnTitor]

Should I move these flags to libc/src/unix/bsd/mod.rs?

I guess we can but we may need additional investigation so the answer is "if you like" :)
Also, CI will fail because of apple 32-bit targets, I fixed CI on master so could you rebase? And it'd be great if you could squash commits into one after finishing the work.

[pwang7]

I did rebase and squash, I also moved the flags to libc/src/unix/bsd/mod.rs, but still some errors.

[JohnTitor]

Thanks!

I also moved the flags to libc/src/unix/bsd/mod.rs, but still some errors.

Heh, that's "we may need additional investigation" point. It seems some BSDs don't have some flags (therefore use of undeclared identifier error occurs). We should move them to under /bsd/apple. And MNT_AUTOMOUNTED should be defined as ulonglong in some BSDs.

[pwang7]

BTW, should I move MNT_FORCE from src/unix/bsd/mod.rs to src/unix/bsd/apple/mod.rs?

[JohnTitor]

BTW, should I move MNT_FORCE from src/unix/bsd/mod.rs to src/unix/bsd/apple/mod.rs?

You don't have to.

[JohnTitor]

Looks good! (semver failures are unrelated.)

[JohnTitor]

Thanks!

[pwang7]

Thanks @JohnTitor! This is my first commit to Rust~