Re: [GSOC] Porting Valgrind to Hurd

[Samuel Thibault]

Subhashish Pradhan, le Thu 20 Mar 2014 22:26:15 +0530, a écrit :
> I found kern/syscall_sw.c couple of days ago and was wondering about the
> difference between the .h and .c variants; but I waited for your feedback.
> The implemented traps matter. But are the others a dummy filler to be
> implemented when required?

They are mostly outdated or non-implemented interfaces. At any rate, you
don't have to care about them.

> I also found that there is a coregrind/m_syswrap/syswrap-darwin.c which has
> some mach wrappers. It'd be an interesting reference

Most probably indeed.

> Can a Darwin VM be used to study that or would it be a waste of time?

I'd say just study the source code.

> >> 4. Build a working source under an instance of Hurd - generation of
> >> makefiles, dependencies, and scripts. (The first deliverable)
> >
> > That will probably be very early in the coding period actually. Better
> > get that working, then implement some PRE/POST, and check that those are
> > working.
> 
> Hmm. Yes, that would be a better way - I could write client programs
> that use those RPCs

Those system calls.

Take care of understanding the difference between RPCs and system calls.
*All* RPCs go through the mach_msg_trap system call. It means
implementing mach_msg_trap correctly in valgrind gives you all RPCs
working.

> >> Q1 - May I port the newest version of Valgrind or should it pose a problem?
> >
> > Better start with the latest rather than having to merge with a newer
> > version.
> 
> By latest do you mean the trunk version, I presume? Or the current release?

I'd say rather the current release.

> Sorry for the big, detailed reply.

No problem, on the contrary, that's what mails are good for.

Samuel