Re: [PATCH] hw: virtio-gpu: remove duplicated 'virtqueue_pop'

[Gerd Hoffmann]

  Hi,

> - If the get_next() invocation is simple, then style (1) is perfectly fine.

Fully agree.  Duplicating a single line is perfectly fine if it is
simple enough that you can hardly get it wrong.

> - Style (2) is the worst of all.

Yes, especially because the break is three lines not two due to qemu
code style.

> - If style (1) is not appropriate for whatever reason, then style (3) is 
> frequently a good replacement. Style (3) is sometimes rejected by coding 
> style documents though. Style (3) is not usable if is_valid() is a 
> function-like macro that does not evaluate its argument exactly once. 
> Frequently, is_valid() is simply open-coded with C operators (using extra 
> parens), for example:

> or more verbosely
> 
>     while ((cmd = virtqueue_pop(vq, sizeof(struct virtio_gpu_ctrl_command))) 
> !=
>            NULL) {

Style 3 tends to generate long lines, which in turn need line breaks
like this.  Also many parens don't help making code more readable.
So I'd prefer to just leave things as-is.

take care,
  Gerd