Re: [Qemu-devel] [PATCH 2/4] virtio-serial: Clean up virtser_bus_dev_print() output

[Markus Armbruster <armbru@redhat.com>]

Andreas Färber <andreas.faerber@web.de> writes:

> Am 19.05.2011 um 16:18 schrieb Markus Armbruster:
>
>> Amit Shah <amit.shah@redhat.com> writes:
>>
>>> On (Thu) 19 May 2011 [13:37:15], Markus Armbruster wrote:
>>>> Old version looks like this in info qtree (last four lines):
>>>>
>>>>          dev: virtconsole, id ""
>>>>            dev-prop: is_console = 1
>>>>            dev-prop: nr = 0
>>>>            dev-prop: chardev = <null>
>>>>            dev-prop: name = <null>
>>>>             dev-prop-int: id: 0
>>>>             dev-prop-int: guest_connected: 1
>>>>             dev-prop-int: host_connected: 0
>>>>             dev-prop-int: throttled: 0
>>>>
>>>> Indentation is off, and "dev-prop-int" suggests these are properties
>>>> you can configure with -device, which isn't the case.  The other
>>>> buses' print_dev() callbacks don't do that.  For instance, PCI's
>>>> output looks like this:
>>>>
>>>>        class Ethernet controller, addr 00:03.0, pci id 1af4:1000
>>>> (sub 1af4:0001)
>>>>        bar 0: i/o at 0xffffffffffffffff [0x1e]
>>>>        bar 1: mem at 0xffffffffffffffff [0xffe]
>>>>        bar 6: mem at 0xffffffffffffffff [0xfffe]
>>>>
>>>> Change virtser_bus_dev_print() to that style.  Result:
>>>>
>>>>          dev: virtconsole, id ""
>>>>            dev-prop: is_console = 1
>>>>            dev-prop: nr = 0
>>>>            dev-prop: chardev = <null>
>>>>            dev-prop: name = <null>
>>>>            port 0, guest on, host off, throttle off
>>>
>>> Here the original guest_connected and host_connected meant whether
>>> the
>>> endpoints were open.  guest on/off, host on/off don't convey that
>>> meaning.  Can't think of a short version, can you?
>>
>> I chose on/off to stay consistent with how qdev shows bool properties
>> (print_bit() in qdev-properties.c).  May be misguided.  Like you, I'm
>> having difficulties coming up with a better version that is still
>> consise.
>
> Erm, I'm not aware that my qdev bool patch got committed yet, so the
> question of how to parse/print bool properties (on/off vs. yes/no) is
> still undecided, no comments so far.

No, there is precedence: PROP_TYPE_BIT's parse_bit(), print_bit().  The
fact that it's a bit within a uint32_t rather than bool is
implementation detail that shouldn't matter at the -device / info qtree
level.

>                                      It would be entirely possible to
> let the author decide that on a case-by-case basis by using different
> property type enums for the same 'bool' type.

Possible, but is it wise?