Re: [Qemu-devel] [PATCH v2] io: fix handling of EOF / error conditions in websock GSource

[Daniel P . Berrangé]

ping

On Thu, Mar 07, 2019 at 04:58:24PM +0000, Daniel P. Berrangé wrote:
> We were never reporting the G_IO_HUP event when an end of file was hit
> on the websocket channel.
> 
> We also didn't report G_IO_ERR when we hit a fatal error processing the
> websocket protocol.
> 
> The latter in particular meant that the chardev code would not notice
> when an eof/error was encountered on the websocket channel, unless the
> guest OS happened to trigger a write operation.
> 
> This meant that once the first client had quit, the chardev would never
> listen to accept a new client.
> 
> Fixes launchpad bug 1816819
> Signed-off-by: Daniel P. Berrangé <address@hidden>
> ---
> 
> Changed in v2:
>  - Fix typo
>  - Remove use of G_IO_IN at same time as HUP/ERR since. It is
>    not required since the websock source doesn't do a real
>    poll itself.
> 
>  io/channel-websock.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/io/channel-websock.c b/io/channel-websock.c
> index dc43dc6bb9..77d30f0e4a 100644
> --- a/io/channel-websock.c
> +++ b/io/channel-websock.c
> @@ -1225,12 +1225,18 @@ qio_channel_websock_source_check(GSource *source)
>      QIOChannelWebsockSource *wsource = (QIOChannelWebsockSource *)source;
>      GIOCondition cond = 0;
>  
> -    if (wsource->wioc->rawinput.offset || wsource->wioc->io_eof) {
> +    if (wsource->wioc->rawinput.offset) {
>          cond |= G_IO_IN;
>      }
>      if (wsource->wioc->encoutput.offset < QIO_CHANNEL_WEBSOCK_MAX_BUFFER) {
>          cond |= G_IO_OUT;
>      }
> +    if (wsource->wioc->io_eof) {
> +        cond |= G_IO_HUP;
> +    }
> +    if (wsource->wioc->io_err) {
> +        cond |= G_IO_ERR;
> +    }
>  
>      return cond & wsource->condition;
>  }
> -- 
> 2.20.1
> 

Regards,
Daniel
-- 
|: https://berrange.com      -o-    https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org         -o-            https://fstop138.berrange.com :|
|: https://entangle-photo.org    -o-    https://www.instagram.com/dberrange :|