On Fri, 2025-09-12 at 16:01 +0200, Markus Armbruster wrote:
> Cc: libvirt
>
> Filip Hejsek <[email protected]> writes:
>
> > From: Szymon Lukasz <[email protected]>
> >
> > The managment software can use this command to notify QEMU about the
> > size of the terminal connected to a chardev, QEMU can then forward this
> > information to the guest if the chardev is connected to a virtio console
> > device.
> >
> > Signed-off-by: Szymon Lukasz <[email protected]>
> > Suggested-by: Daniel P. Berrangé <[email protected]>
> > Signed-off-by: Filip Hejsek <[email protected]>
> > ---
> > chardev/char.c | 14 ++++++++++++++
> > qapi/char.json | 22 ++++++++++++++++++++++
> > 2 files changed, 36 insertions(+)
> >
> > diff --git a/chardev/char.c b/chardev/char.c
> > index
> > b45d79cb9b57643827eb7479257fdda2cf6b0434..6e3ade98614c949be8041ec5905a490ff536dee9
> > 100644
> > --- a/chardev/char.c
> > +++ b/chardev/char.c
> > @@ -1269,6 +1269,20 @@ bool qmp_add_client_char(int fd, bool has_skipauth,
> > bool skipauth,
> > return true;
> > }
> >
> > +void qmp_chardev_resize(const char *id, uint16_t cols, uint16_t rows,
> > + Error **errp)
> > +{
> > + Chardev *chr;
> > +
> > + chr = qemu_chr_find(id);
> > + if (chr == NULL) {
> > + error_setg(errp, "Chardev '%s' not found", id);
> > + return;
> > + }
> > +
> > + qemu_chr_resize(chr, cols, rows);
> > +}
> > +
> > /*
> > * Add a timeout callback for the chardev (in milliseconds), return
> > * the GSource object created. Please use this to add timeout hook for
> > diff --git a/qapi/char.json b/qapi/char.json
> > index
> > f0a53f742c8bee24c377551803a864fd36ac78cf..0a26c5eee6b71bc5de127a91b253cc69a9fe8ce6
> > 100644
> > --- a/qapi/char.json
> > +++ b/qapi/char.json
> > @@ -874,6 +874,28 @@
> > { 'command': 'chardev-send-break',
> > 'data': { 'id': 'str' } }
> >
> > +##
> > +# @chardev-resize:
>
> This name doesn't tell me what is being resized. PATCH 04 uses
> "winsize", which is better. The (losely) related SIGWINCH suggests
> "window change" or "window size change". Below, you use "terminal
> size".
How about chardev-console-resize? That would match the name of the
virtio event (VIRTIO_CONSOLE_RESIZE).
> > +#
> > +# Notifies a chardev about the current size of the terminal connected
> > +# to this chardev.
>
> Yes, but what is it good for? Your commit message tells: "managment
> software can use this command to notify QEMU about the size of the
> terminal connected to a chardev, QEMU can then forward this information
> to the guest if the chardev is connected to a virtio console device."
How about:
Notifies a chardev about the current size of the terminal connected
to this chardev. The information will be forwarded to the guest if
the chardev is connected to a virtio console device.
> > +#
> > +# @id: the chardev's ID, must exist
> > +# @cols: the number of columns
> > +# @rows: the number of rows
>
> Blank lines between the argument descriptions, bease.
>
> What's the initial size?
0x0
> Do we need a way to query the size?
I don't think it is necessary. What would be the usecase for that?
> > +#
> > +# Since: 10.2
> > +#
> > +# .. qmp-example::
> > +#
> > +# -> { "execute": "chardev-resize", "arguments": { "id": "foo",
> > "cols": 80, "rows": 24 } }
> > +# <- { "return": {} }
> > +##
> > +{ 'command': 'chardev-resize',
> > + 'data': { 'id': 'str',
> > + 'cols': 'uint16',
> > + 'rows': 'uint16' } }
> > +
> > ##
> > # @VSERPORT_CHANGE:
> > #
