From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68070C433DB for ; Thu, 28 Jan 2021 17:17:25 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E841964DE2 for ; Thu, 28 Jan 2021 17:17:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E841964DE2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:36726 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l5Av4-0001Vs-1u for qemu-devel@archiver.kernel.org; Thu, 28 Jan 2021 12:17:23 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:48948) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l5AqX-0007Vk-Qd for qemu-devel@nongnu.org; Thu, 28 Jan 2021 12:12:41 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:34072) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l5AqT-0005cI-Vi for qemu-devel@nongnu.org; Thu, 28 Jan 2021 12:12:41 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611853956; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=qCaVP+kxSpYlZpblZN5bwNYbTLAYEX752Qa3HCB48Lo=; b=exLg6OSb0gu1DwFA7KijEHXqdi2/3oc3B1jr/MdO0qjVobcGXufttfgj2mvAxvNjNw8MSH Gm1h9DYksnII24S/7sXLQWKqtQg1xG4v/O/xEzqW/UMI31vBsuMrShvi0wv2uI9hm0bP04 /MuoHiSkCXu5DckM1qW0V2T0/ehfcLY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-599-XXRmJua2Om-kAtO6hRKqHw-1; Thu, 28 Jan 2021 12:12:31 -0500 X-MC-Unique: XXRmJua2Om-kAtO6hRKqHw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AA8011936B66 for ; Thu, 28 Jan 2021 17:12:29 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-113-27.ams2.redhat.com [10.36.113.27]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 727FC60C69 for ; Thu, 28 Jan 2021 17:12:29 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id A094D18000B1; Thu, 28 Jan 2021 18:12:24 +0100 (CET) Date: Thu, 28 Jan 2021 18:12:24 +0100 From: Gerd Hoffmann To: qemu-devel@nongnu.org Subject: vnc clipboard support Message-ID: <20210128171224.exbklnwtyb232oe2@sirius.home.kraxel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kraxel@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=kraxel@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.252, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Hi folks, I'm looking for a good way to implement cut+paste support for vnc. The vnc core protocol has support for text/plain cut+paste, and there is an extension adding support for other formats. That'll cover one part of the problem, exchanging cut+paste data between vnc client and qemu vnc server. The tricky part is the second: the guest <=> qemu communication. I see basically two possible approaches here: (1) Have some guest agent (spice does it that way). Advantage: more flexible, allows more features. Disadvantage: requires agent in the guest. (2) Send text as key events. Advantage: no guest agent needed. Disadvantage: is translated by guests keyboard map, so qemu needs to know the map for proper char -> key event translation. Only works for text/plain and only for chars you can easily type, anything needing input methods (emoji 😊 for example) isn't going to fly. I think that (1) is clearly the better way. Given that the agent would need to run in user wayland/xorg session context the existing qemu-guest-agent will not work. Also linking against some UI library like gtk3 for clipboard handling is not something we want for the qemu-guest-agent. So we need another one, I'll name it qemu-clipboard-agent for the rest of this mail. And we need a communication channel. I'd tend to model the qemu-clipboard-agent simliar to the qemu-guest-agent, i.e. have some stream as communication path and run some stream protocol over it. Stream options I see are (in order of personal preference): (1) New virtio-serial port. virtio-serial likely is there anyway for the qemu-guest-agent ... (2) Have qemu-clipboard-agent and qemu-guest-agent share the agent channel, i.e. qemu-clipboard-agent will proxy everything through qemu-guest-agent (spice does it that way). Protocol options I see are (not sure yet which to prefer, need to have a closer look at the candidates): (1) Add clipboard commands to QMP and use these. (2) Reuse the clipboard bits of the vnc protocol (forward VNC_MSG_CLIENT_CUT_TEXT messages to the guest agent) (3) Reuse the clipboard bits of the spice-agent protocol. (4) Reuse the clipboard bits of the wayland protocol. Once we have sorted the qemu <-> guest communication path it should be possible to also hook up other UIs (specifically gtk) without too much effort. Which probably makes (2) a rather poor choice. Comments? Suggestions? Other ideas? take care, Gerd