From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57125) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cY9YT-0005kD-Dt for qemu-devel@nongnu.org; Mon, 30 Jan 2017 05:51:26 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cY9YQ-0002Xw-AI for qemu-devel@nongnu.org; Mon, 30 Jan 2017 05:51:25 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58092) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cY9YQ-0002VB-4a for qemu-devel@nongnu.org; Mon, 30 Jan 2017 05:51:22 -0500 From: "Daniel P. Berrange" Date: Mon, 30 Jan 2017 10:51:16 +0000 Message-Id: <20170130105116.29337-1-berrange@redhat.com> Subject: [Qemu-devel] [PATCH] io: fix decoding when multiple websockets frames arrive at once List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Brian Rak , "Daniel P. Berrange" The qio_channel_websock_read_wire() method will read upto 4096 bytes off the socket and then decode the websockets header and payload. The code was only decoding a single websockets frame, even if the buffered data contained multiple frames. This meant that decoding of subsequent frames was delayed until further input arrived on the socket. This backlog of delayed frames gets worse & worse over time. Symptom was that when connecting to the VNC server via the built-in websockets server, mouse/keyboard interaction would start out fine, but slowly get more & more delayed until it was unusable. Signed-off-by: Daniel P. Berrange --- io/channel-websock.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/io/channel-websock.c b/io/channel-websock.c index e47279a..a06a4a8 100644 --- a/io/channel-websock.c +++ b/io/channel-websock.c @@ -570,21 +570,24 @@ static ssize_t qio_channel_websock_read_wire(QIOChannelWebsock *ioc, ioc->encinput.offset += ret; } - if (ioc->payload_remain == 0) { - ret = qio_channel_websock_decode_header(ioc, errp); + while (ioc->encinput.offset != 0) { + if (ioc->payload_remain == 0) { + ret = qio_channel_websock_decode_header(ioc, errp); + if (ret < 0) { + return ret; + } + if (ret == 0) { + ioc->io_eof = TRUE; + break; + } + } + + ret = qio_channel_websock_decode_payload(ioc, errp); if (ret < 0) { return ret; } - if (ret == 0) { - return 0; - } } - - ret = qio_channel_websock_decode_payload(ioc, errp); - if (ret < 0) { - return ret; - } - return ret; + return 1; } @@ -642,9 +645,6 @@ static gboolean qio_channel_websock_flush(QIOChannel *ioc, if (ret < 0) { goto cleanup; } - if (ret == 0) { - wioc->io_eof = TRUE; - } } cleanup: -- 2.9.3