Re: [BackupPC-users] backuppc, rsync, freebsd

[<cba...@us...>]

Marlin Prowell writes:

> I finally took some time to track down this bug.  The patch is listed below.
> 
> There is a small perl module, File::RsyncP, that backuppc requires.  I 
> wrote a short perl script that uses this perl module to imitate what 
> backuppc does when using rsync.  I found the same problem mentioned above 
> when using the perl script, so I knew the bug was somewhere inside the perl 
> module, and not in backuppc itself.
> 
> This bug is not specific to FreeBSD.  It can occur on all OS versions.  I 
> surmise that the malloc routines are different between FreeBSD and Linux, 
> and so the bug is exposed quicker in FreeBSD.
> 
> I have a backuppc test task that uses rsync.  All my production backups use 
> tar.  The test task has failed 99 consecutive times over the last 
> month.  It finally succeeded in performing a full backup after making this 
> change to File::RsyncP.  I don't know if this is the only problem I have 
> had, and I will keep expanding my tests as long as the current tests 
> succeed.  But I thought I would publish this fix, since it has fixed some 
> rsync problems I have had.

Thank you!!  I looked at your patch and it definitely fixes a subtle
problem with receiving the file list.  If the file list is fragmented in
a certain way, the code incorrectly updates f->lastdir and then returns
to the caller to fetch more data.  This could trash the starting part of
the directory name on future files.  Your patch fixes that.

I'll do a new release of File::RsyncP with this patch, hopefully
next weekend.

Thanks again.

Craig