cancellation variant for uClibc?

[Peter S. Mazinger]

On Thu, 24 Aug 2006, Carmelo AMOROSO wrote:

> Yes, this is one of the main question I was going to ask to Steve, 
> before starting to merge his code with mine
> (I mean the uClibc-nptl port for SuperH at STMicro)
> 
> >For the Arm port we added the cancellation code (with appropriate macros) 
> >directly into the existing implementations.
> >  
> >
> This is the same approach we used, so if you don't use the NPTL pthread 
> implementation, the __libc_XXX functions
> will be not cancellable. And we have only one implementation into libc.

Then I would propose to do that for all threads variants, get rid of the 
__libc_x versions, no need for wrapsyscall.c in linuxthreads_old

Consider though to replace all the similar code starting with
if (SINGLE_THREAD_P)
	...
with a macro like in wrapsyscall.c (I have proposed this when I commented 
on the arm port already)


> We provided both a cancellable/not cancellable implementation for some  
> functions (open - close - read - write - waitpid)
> requiring both implementation (they are used into 'hostid.c'). They must 
> we invoked as <function>_nocancel explicitly (see <not-cancel.h> for 
> reference).
not-cancel.h is also a header that should be addable unconditionally to 
each source file, I would propose something like this to be added to it
#ifndef __UCLIBC_HAS_THREADS__
#define <function>_nocancel somefunc
#endif
for all functions that have cancellable/not cancellable pairs
I assume <function>_nocancel are implemented as non-visible in userspace

Peter
> 
> Furthermore, the Steve approach, using the PSEUDO macro from 
> <sysdep-cancel-h> is adding to the library, for each function,
> the relative XXX_nocancel symbol, and I'm not sure it needs.
> 
> We already synchronized our code with the arm port to simply the merge, 
> but the logic behind
> was the same from the beginning.
> 
> Carmelo
> 
> >Paul
> >_______________________________________________
> >uClibc mailing list
> >uClibc at uclibc.org
> >http://busybox.net/cgi-bin/mailman/listinfo/uclibc
> >
> >  
> >
> 
> 

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Peter S. Mazinger <ps dot m at gmx dot net>           ID: 0xA5F059F2
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