Re: [Qemu-devel] [PATCH 24/24] QemuOpts: Fix checking of sizes for overflow and trailing crap

[Markus Armbruster <armbru@redhat.com>]

Eric Blake <eblake@redhat.com> writes:

> On 02/14/2017 04:26 AM, Markus Armbruster wrote:
>> parse_option_size()'s checking for overflow and trailing crap is
>> wrong.  Has always been that way.  qemu_strtosz() gets it right, so
>> use that.
>> 
>> This adds support for size suffixes 'P', 'E', and ignores case for all
>> suffixes, not just 'k'.
>
> Yay! Be liberal in what you accept!  (I've always been annoyed that '-m
> 1g' complains, forcing me to us '-m 1G').

The liberality is okay when we measure bytes, because 'm' can only mean
"mega" there.  It's problematic when we measure things like seconds,
where 'm' definitely should mean "milli".

Perhaps I should make do_strtosz() case-insensitive only when unit ==
1024, but not when unit == 1000.

> Okay, we're at the end of the series, and I've pointed out other
> possible improvements.  As mentioned elsewhere, it might be nice to add
> a 25/24 to match coreutils, which allows 'm' and 'mib' to mean
> 1024*1024, vs. 'mb' to mean 1000*1000.  Right now, all clients of
> qemu_strtosz() are stuck to one scale, vs. letting the user choose a
> scale by their choice of suffix.  But it does not hold up this series if
> you don't like the idea.

I'd prefer not to do that now, because I'm busy on getting -blockdev
done before the soft freeze.

>> Signed-off-by: Markus Armbruster <armbru@redhat.com>
>> ---
>>  tests/test-qemu-opts.c | 21 +++++++++------------
>>  util/qemu-option.c     | 41 +++++++++++++----------------------------
>>  2 files changed, 22 insertions(+), 40 deletions(-)
>> 
>
> Reviewed-by: Eric Blake <eblake@redhat.com>

Thanks!