Re: [Qemu-devel] [PATCH V2 07/12] qmp: add internal snapshot support in qmp_transaction

[Stefan Hajnoczi]

On Fri, Jun 14, 2013 at 07:39:54PM +0800, Wenchao Xia wrote:
> +    /* Forbid having a name similar to id, empty name is also forbidden. */
> +    if (!snapshot_name_wellformed(name)) {
> +        error_setg(errp, "Name %s on device %s is not a valid one",

Please use '%s' instead of just %s for arguments in error messages.
This will make the message easier to understand, especially when name is
empty.  It's also consistent with the rest of blockdev.c.

> +                   name, device);
> +        return;
> +    }
> +
> +    /* 3. take the snapshot */
> +    sn1 = &state->sn;
> +    pstrcpy(sn1->name, sizeof(sn1->name), name);
> +    qemu_gettimeofday(&tv);
> +    sn1->date_sec = tv.tv_sec;
> +    sn1->date_nsec = tv.tv_usec * 1000;
> +    /* not good to use vm_clock in block layer, but that is what we can do 
> now,
> +       or drop it later, since it is an emulater concept. */

It's appropriate here and blockdev.c is emulator code, so you can drop
the comment.