[pulseaudio-discuss] How to debug a "protocol error" message?

[Maarten Bosmans]

2011/5/23 Quinn Plattel <qiet72 at gmail.com>:
> Hi,
>
> I am currently having problems with communication between a version 0.9.22
> pulseaudio client and a version 0.9.15 pulseaudio server.
> Here are the steps to reproduce the error message:
> pulseaudio server side: ssh -X -R 4713:localhost:4713
> <remote-pulseaudio-client> "PULSE_SERVER=localhost:4713 pactl stat"
>
> client reports:
> ------------------------
> Using shared memory pool with 1024 slots of size 64.0 KiB each, total size
> is 64.0 MiB, maximum usable slot size is 65472
> Trying to connect to localhost:4713...
> SHM possible: yes
> Protocol version: remote 16, local 16
> Negotiated SHM: no
> Connection failure: Connection terminated
> -------------------------
>
> server reports:
> --------------------------
> protocol error, kicking client
> --------------------------
>
> I have done some testing and a 0.9.15 server has no problems communicating
> with a 0.9.14 client, but
> a 0.9.15 server has this error when communicating with a 0.9.19 or 0.9.22
> client.
>
> Where do I begin to debug this error?

The difficulty here is of course that while the server throws an
error, you're looking to fix the client side, because there won't be a
maintainance release of the 0.9.15 series anymore.

If you can install debug symbols, you can set a breakpoint at
protocol_error(). This will break in command_stat()
(src/pulsecore/protocol-native.c), right after the
!pa_tagstruct_eof(t) check. There you can inspect what kind of
unexpected extra data is in the tagstruct and take it from there.

Please also try whether other commands work.

Maarten