[Pkg-samba-maint] Bug#759008: Bug#759008: libtdb1: FTBFS on hurd-i386

[Manuel Menal]

On 23/08/2014 22:27, Jelmer Vernooij wrote:
> block 759008 by 748943
> tags 759008 -patch
> thanks
>
> Hi Manuel,
Hello,
> On Sat, Aug 23, 2014 at 02:30:33PM -0400, Manuel Menal wrote:
>> tdb fails to build on hurd-i386 (blocking ldb and thus samba) because
>> it uses two features that are not yet implemented on GNU/Hurd: msync(1)
>> and partial file locking.
>>
>> You'll find attached two small patches that make it build.
>>
>> The first patch adds a configure test for partial file locking and make
>> tdb use whole file locking when it's not supported.
>>
>> The second one adds a configure test for msync(1) and correct tdb's
>> code accordingly.
>>
>> Please note that this package should be built with 'nocheck' because
>> some tests do not run well without partial file locking. The tools in
>> tdbtools/ run fine though.
>>
>> Please also note that hurd-any should be added to debian/control so it
>> gets built on hurd-i386.
> The whole point of tdb is that it allows multiple concurrent
> readers/writers, and that is why the various applications that depend
> on tdb use it.
Yes, I get that. But that doesn't mean it doesn't work without this 
patch, since samba actually works with this, which was the point.
> This patch might make tdb build, but it makes it pointless. Any
> patches to fix tdb on the Hurd the should also pass the test
> suite, or downstream users risk database corruption and/or other
> issues.
The only tests that fail are those which check specifically for partial 
file locking (test/lock-tracking.c specifically checks for lock 
overlaps, which of course happen since the whole file is locked; which 
makes run-die-during-transaction and run-no-lock-during-traverse fail).

I fail to see how it could cause database corruption, since, indeed, the 
whole file is always locked. The only thing it does (as you rightly 
pointed out) is limit functionality.
> Please fix byte range locking in the Hurd (see the blocking bug I've
> added), or propose a patch that uses an alternative *and* passes the
> test suite.
I do hope too that partial file locking gets implemented on GNU/Hurd 
ASAP. But in the meantime, it would be a shame not to have a working 
samba, when it *does* work fine with this patch.
> Cheers,
Thank you for your answer,
> Jelmer
-- 
Manuel Menal