[Libguestfs] [PATCH 09/10] New API: mksquashfs

[Richard W.M. Jones]

On Wed, Feb 15, 2017 at 11:06:34AM +0100, Pino Toscano wrote:
> On Tuesday, 14 February 2017 16:33:57 CET Richard W.M. Jones wrote:
> > On Tue, Feb 14, 2017 at 09:12:10AM +0100, Pino Toscano wrote:
> > > Introduce a new API to create a new squashfs filesystem out of a path
> > > in the guest.  It can be configured to exclude paths based on patterns,
> > > and to select which compression use for the filesystem.
> > > 
> > > The advantage of running mksquashfs directly in the appliance is that
> > > ownerships are properly saved, as opposed to tar_out + local untar.
> > 
> > I'm fairly sure this was proposed before as an API, but I cannot find
> > that right now.  Was rejected because mksquashfs doesn't support
> > streaming output.
> 
> Yes, and it does not have any streaming for input either, so things
> like `cat my.tar | mksquashfs - my.squash` cannot be done :-(
> 
> > However I'm fine with this, although perhaps there should be a warning
> > in the longdesc saying that there may be problems with large files.  I
> > think this API will break in the region of 3GB.
> 
> Also because the temporary squashfs file is stored inside the appliance,
> which has < 3.5G space available.
> 
> It makes sense -- what about the following addendum to the longdesc?
> 
>   Please note that this API may fail when used to compress directories
>   with large files, such as the resulting squashfs will be over 3GB big.

Yup, seems reasonable.  (ACK series BTW in case I wasn't clear
about that yesterday).

Thanks,

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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