On 24 Mar 2016, at 12:05, mokhi <mokh...@gmail.com> wrote:
> Hi.
> I'm agreed with point you told about improvements we can do for fat
> format (or more).
> And I'm ready to do them (with your helps, sure :D).
> But we need short steps and more of them (a local proverb :D) IMO.
> If we completely do this image activator, then we can have 2 sub plans
> for OSX emulation and/or fat data segment redesign.

FatELF binaries do not depend on this work.  Fat Mach-O binaries do, but the 
pain of working with Mach-O is not worth it (talk to some of the Apple 
toolchain team some time about how much effort Mach-O is - I’m glad it’s their 
problem and not mine).

I don’t believe that the work to support FatELF would be particularly large.  
The format is pretty simple (basically a small header that tells you where 
within the binaries to find the real ELF for your architecture).  Teaching all 
of the associated bits of the toolchain (especially debuggers) about it is a 
lot of tedious work, but not particularly hard if someone is motivated to do 
it.  Teaching clang and lld to produce fat binaries as part of normal ELF 
compilation would be a bit more work.

> I saw netbsd's way of mach-kernel/darwin emulation.
> They have been stopped in porting/simulating quartz (the reason
> described lack of developers' interest IIRC), and that relates to OSX
> emulating.

That wasn’t the only reason.  The XNU kernel interfaces for graphics and sound 
are large and mostly undocumented (at least, publicly) and change between OS X 
revisions.  Even if you implement *all* of this, then you’d still need most of 
an OS X userland to be able to run OS X applications.  This would involve 
violating the OS X EULA unless you ran it on a Mac and the only thing that 
you’d then be able to do that you couldn’t with OS X is run FreeBSD binaries in 
the background or in XQuartz (which you can already do pretty well with xhyve 
on OS X).  If you are willing to violate the OS X EULA then you should probably 
just run OS X in a VM.

> If we wanna complete/continue that way, first we need this image
> activator, what's your opinion about it?
> BTW, in brief I believe we can have strategies to do (sub plans) and
> it worth (at least for me, because I'll learn good things). What's
> your opinion?

As a learning exercise, I definitely encourage you to continue.  Writing a new 
image activator will teach you a lot.  If you want to do some of the rtld work 
to make a partial Mach-O rtld then you’ll learn even more.  I just don’t think 
that the end result will be something that’s particularly useful to anyone.


freebsd-current@freebsd.org mailing list
To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"

Reply via email to