Re: [Qemu-devel] [PATCH] qcow2: remove useless NULL check

["Marc-André Lureau" <mlureau@redhat.com>]

Hi

----- Original Message -----
> On 08.02.2017 09:09, Marc-André Lureau wrote:
> > g_strdup() already handles the case where the argument is NULL.
> > 
> > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> > ---
> >  block/qcow2.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git a/block/qcow2.c b/block/qcow2.c
> > index 96fb8a8f16..9114218030 100644
> > --- a/block/qcow2.c
> > +++ b/block/qcow2.c
> > @@ -2016,8 +2016,8 @@ static int qcow2_change_backing_file(BlockDriverState
> > *bs,
> >      g_free(s->image_backing_file);
> >      g_free(s->image_backing_format);
> >  
> > -    s->image_backing_file = backing_file ? g_strdup(bs->backing_file) :
> > NULL;
> > -    s->image_backing_format = backing_fmt ? g_strdup(bs->backing_format) :
> > NULL;
> > +    s->image_backing_file = g_strdup(bs->backing_file);
> > +    s->image_backing_format = g_strdup(bs->backing_format);
> 
> bs->backing_file and bs->backing_format are arrays. They will never be NULL.
> 
> The ternary operator tests backing_file and backing_fmt which instead
> are pointers. So this is not an equivalent conversion.

oops my bad, ignore ;P a bit uncommon code though, could deserve a comment.


> 
> Max
> 
> >  
> >      return qcow2_update_header(bs);
> >  }
> > 
> 
> 
>