Re: [PATCH v5 02/28] btrfs: Get zone information of zoned block devices

David Sterba
2019-12-04T17:22:42Z

On Wed, Dec 04, 2019 at 04:37:32PM +0100, Johannes Thumshirn wrote:
> On Wed, Dec 04, 2019 at 05:17:09PM +0900, Naohiro Aota wrote:
> [..]
>
> > +#define LEN (sizeof(device->fs_info->sb->s_id) + sizeof("(device )") - 1)
> > + char devstr[LEN];
> > + const int len = LEN;
> > +#undef LEN
>
> Why not:
> const int len = sizeof(device->fs_info->sb->s_id)
> + sizeof("(device )") - 1;
> char devstr[len];

len is used only once for snprintf to devstr, so there it can be
replaced by sizeof(devstr) and the sizeof()+sizeof() can be used for
devstr declaration.

The size of devstr seems to be one byte shorter than needed:

> > + snprintf(devstr, len, " (device %s)",
> > + device->fs_info->sb->s_id);

There's a leading " " at the begining that I don't see accounted for.