[libvirt] [PATCH] support lzop save compression for qemu

[Jim Meyering]

Chris Lalancette wrote:

> Jim Meyering wrote:
>> Chris Lalancette wrote:
>>> Charles Duffy wrote:
>>>> Per prior discussion -- this was, indeed, trivial.
>>>>
>>>> I'm a little disappointed to be breaking the ordering characteristics of
>>>> the enum (as it had been ordered by increasing time requirements and
>>>> decreasing output size), but breaking any save files with the old
>>> Heh, that was completely an accident; I just added them as I implemented them.
>>> So no loss there.
>>>
>>> ACK to the patch.
>>
>> Hi Chris,
>>
>> FYI, in the context of that patch, I noticed compression support (nice!),
>> and LZMA support in particular, but none for xz, which is the successor
>> to lzma.  <http://tukaani.org/xz/>
>>
>> Now that XZ's format is stable, and xz is in F11, you may
>> want to support it, too.
>>
>> Actually, since lzma is deprecated, and support for it in libvirt
>> went in only 3 weeks ago, you may want to remove it completely,
>> in favor of xz.
>
> Hey Jim,
>      Right, I noticed that as I was developing this (and another patch).  The
> situation between xz and lzma wasn't completely clear to me, so thanks for
> clarifying a little.  The thing is, isn't the command-line tool for xz still
> called "lzma"?  Or is the tool called "xz"?

xz is the new format name as well as the new program name.
The LZMA -> XZ format change was big enough that it seemed best to
have a new tool name (though it was a close call, and there was a lot
of debate ;-), in spite of the trouble it causes to users.

However, note that xz can uncompress .lzma files.