svn commit: r355301 - head/usr.sbin/bhyve

[Vincenzo Maffione]

Il giorno lun 2 dic 2019 alle ore 22:14 Ian Lepore <ian at freebsd.org> ha
scritto:

> On Mon, 2019-12-02 at 20:51 +0000, Vincenzo Maffione wrote:
> > Author: vmaffione
> > Date: Mon Dec  2 20:51:46 2019
> > New Revision: 355301
> > URL: https://svnweb.freebsd.org/changeset/base/355301
> >
> > Log:
> >   bhyve: uniform printf format string newlines
> >
> >   Some of the printf statements only use LF to get a newline.
> > However, a CR character is also required for the serial console to
> > print debug logs in a nice way.
> >   Fix those code locations that only use LF, by adding a CR
> > character.
> >
> >   Reviewed by:        markj, aleksandr.fedorov at itglobal.com
> >   MFC after:  1 week
> >   Differential Revision:      https://reviews.freebsd.org/D22552
> >
> > Modified:
> >   head/usr.sbin/bhyve/audio.c
> >   head/usr.sbin/bhyve/hda_codec.c
> >   head/usr.sbin/bhyve/net_backends.c
> >   head/usr.sbin/bhyve/pci_ahci.c
> >   head/usr.sbin/bhyve/pci_e82545.c
> >   head/usr.sbin/bhyve/pci_hda.c
> >   head/usr.sbin/bhyve/pci_nvme.c
> >   head/usr.sbin/bhyve/pci_virtio_block.c
> >   head/usr.sbin/bhyve/pci_virtio_console.c
> >   head/usr.sbin/bhyve/pci_virtio_net.c
> >   head/usr.sbin/bhyve/pci_virtio_rnd.c
> >   head/usr.sbin/bhyve/pci_virtio_scsi.c
> >   head/usr.sbin/bhyve/pci_xhci.c
> >   head/usr.sbin/bhyve/rfb.c
> >
>
> These changes seem wrong in a couple ways...
>
>  - Lines are terminated by linefeeds in unix-like systems.  If
> linefeeds need to be translated to include carriage returns, that's the
> responsibility of the terminal/line-discipline layer, not the source
> strings being printed.
>

That's a good point. The need for carriage returns shows up when using the
vmrun.sh script on a FreeBSD host, which ends up calling /usr/bin/bhyve.
I must admit I don't know enough about the terminals and ldisc to know how
to change the current behaviour and fix this specific issue.
Any suggestions and pointer would be very welcome.

>
>  - The sequence \n\r is very strange.  For systems that do prefer
> carriage returns, the \r always comes before the \n (or stands alone on
> Mac systems), not after.
>

Also true. I did not realize that, and just reused the same sequence that
was used elsewhere.

>
> I have a feeling that the root of this is something like "lots of
> people use bhyve for Windows, so they use Windows apps to look at logs,
> so the logs should be formatted for Windows."  If that's the reasoning,
> then why shouldn't we convert EVERY printf in the source base to
> include carriage returns, just in case a windows user wants to browse a
> log file?
>

No, as I said above this happens with FreeBSD guests on FreeBSD hosts,
using the /share/example/bhyve/vmrun.sh script.

Thanks,
  Vincenzo

>
> -- Ian
>
>