Re: [Qemu-devel] [PATCH] pty: unbreak libvirt

[Anthony Liguori <anthony@codemonkey.ws>]

"Daniel P. Berrange" <berrange@redhat.com> writes:

> On Thu, Jan 03, 2013 at 02:23:03PM +0100, Gerd Hoffmann wrote:
>> Commit 586502189edf9fd0f89a83de96717a2ea826fdb0 breaks libvirt pty
>> support because it tried to figure the pts name from stderr output.
>> 
>> Fix this by moving the label to the end of the line, this way the
>> libvirt parser does still recognise the message.  libvirt looks
>> for "char device redirected to ${ptsname}<whitespace>".
>
> FWIW, libvirt was not supposed to be parsing this data still.
> We rely on query-chardev to get the PTYs, but we were accidentally
> still invoking the stdio parsing code even though we didn't use
> the result :-(

Thanks for the explanation.  I thought about libvirt before applying
this but had figured it was using query-chardev.

I still think this is a reasonable change to make though even if the
latest libvirt doesn't need it so I'll apply it.

Regards,

Anthony Liguori

>
> This flaw is fixed in latest libvirt GIT.
>
>> 
>> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
>> ---
>>  qemu-char.c |    9 +++++----
>>  1 files changed, 5 insertions(+), 4 deletions(-)
>> 
>> diff --git a/qemu-char.c b/qemu-char.c
>> index 331ad5c..f41788c 100644
>> --- a/qemu-char.c
>> +++ b/qemu-char.c
>> @@ -1012,10 +1012,11 @@ static CharDriverState *qemu_chr_open_pty(QemuOpts *opts)
>>      qemu_opt_set(opts, "path", q_ptsname(master_fd));
>>  
>>      label = qemu_opts_id(opts);
>> -    fprintf(stderr, "char device%s%s redirected to %s\n",
>> -            label ? " " : "",
>> -            label ?: "",
>> -            q_ptsname(master_fd));
>> +    fprintf(stderr, "char device redirected to %s%s%s%s\n",
>> +            q_ptsname(master_fd),
>> +            label ? " (label " : "",
>> +            label ? label      : "",
>> +            label ? ")"        : "");
>>  
>>      s = g_malloc0(sizeof(PtyCharDriver));
>>      chr->opaque = s;
>
>
> Daniel
> -- 
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