Fixing threading on NetBSD

[Peter Cooper]

Hi everyone

I'm hoping to get some feedback on a couple of very small mods that were
needed to get NetBSD back up to speed with GNUstep. One of the things that
I need is thread support. While I was looking at that, I noticed a couple
of other things that bugged me ;)

I'm quite interested in whether this helps users of NetBSD on non-i386
platforms. Some of the changes here may help OpenBSD people in getting
threading working...

First off, I'm using the following packages from pkgsrc: gmake-3.79.1nb1,
libiconv-1.8, jpeg-6b, png-1.2.4, tiff-3.5.7, ffcall-1.8.4, libxml2-2.4.24nb1,
gmp-4.1, and pth-2.0.0 (there may be more dependencies, but these are the
ones I recall). I'm using gcc version 2.95.3, which shipped with my
OS distribution.

Due to the unusual (for Linux people at least ;) way of placing pkg
libraries into /usr/pkg/lib and so on, a little more support (-R paths)
was required in make and base at config-time so that dynamic linking works
properly during tests (see attached patches make-configure.ac-patch,
base-configure.ac-patch).

The same was true at runtime for X11-related packages (see the second part 
of the attached make-target.make-patch). I stronly suggest applying these
as users will then not need to modify their /etc/ld.so.conf files.

Every time I did a point release upgrade of NetBSD, without changing a
working GNUstep environment, I'd have to recompile all of the binaries,
or do funky symlinks in the object directories as the operating system
identifier in GNUstep also included the NetBSD version number. A small
fix for this is in the make-cleanos-patch file attached, which assumes
that GNUstep binaries between different NetBSD versions will run unchanged.
I think this is a workable assumption.

Since the legacy objc libraries are a little broken, after first installing
the makefile package and sourcing the environment, it was time to build
and install the GNUstep libobjc to get ffcall support (for DO) and perhaps
threading.

To get the dev-apps/libobjc (btw: why is it not in dev-libs?) library to 
support pth 2.0, a GNU co-operative threading library that has its'
own semantics as well as some POSIX support, I needed to modify thr-posix.c
a little. 

I applied the very small change attached to this mail to thr-posix.c -
NetBSD doesn't have any real sched_* support right now, and certain
optional POSIX threading capabilities are missing, like priority scheduling,
so a couple of things needed to be wrapped in an #if structure.

To do this without breaking other platforms, I've copied thr-posix.c to
thr-pth.c and applied the attached patch, libobjc-pth-patch. To support
this, I also applied a patch to the makefile so that the right support
file was used: libobjc-mf-patch.

[This is fairly ugly, and I'm not sure how this can be rolled into the
GNUstep libobjc distribution, primarily because of the awful sched_*
brokenness in production releases of NetBSD. Suggestions?]

Anyway, after this was installed, I reconfigured the makefile package
with --with-thread-lib="-lpthread". The first part of the previously
mentioned target.make patch differs from other platform support of 
threading a little; if you link pth into thread-unaware c source (ctools
like gdomap, for example), there is an automatic core-dump when doing
network IO. So, to avoid linking libpthread to ctools and so on, 
rather than adding the threading library options to TARGET_SYSTEM_LIBS,
I added them to AUXILIARY_OBJC_LIBS.

NSThread seems to work fairly well now, gdomap doesn't core dump, and
I'll be looking at getting GNUmail soon.

I'd very much like the non-controversial bits of these patches added
to the distribution, but I'm a bit concerned that some of the changes
are fairly different/ugly. Are there better ways to get some of these
things working?

Comments and commit announcements ;) would be very welcome.

Peter

make-cleanos-patch
Description: Text document

make-target.make-patch
Description: Text document

make-configure.ac-patch
Description: Text document

libobjc-pth-patch
Description: Text document

libobjc-mf-patch
Description: Text document

base-configure.ac-patch
Description: Text document