[pulseaudio-discuss] [PATCH 11/11] protocol-native: Enable srchannel

[Tanu Kaskinen]

On Tue, 2014-04-29 at 15:22 +0200, David Henningsson wrote:
> The srchannel is enabled if protocol version >= 30 and
> SHM is available.
> 
> Signed-off-by: David Henningsson <david.henningsson at canonical.com>
> ---
>  src/pulsecore/protocol-native.c | 44 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 44 insertions(+)
> 
> diff --git a/src/pulsecore/protocol-native.c b/src/pulsecore/protocol-native.c
> index 65b2636..c2ec644 100644
> --- a/src/pulsecore/protocol-native.c
> +++ b/src/pulsecore/protocol-native.c
> @@ -2568,6 +2568,45 @@ static void command_exit(pa_pdispatch *pd, uint32_t command, uint32_t tag, pa_ta
>      pa_pstream_send_simple_ack(c->pstream, tag); /* nonsense */
>  }
>  
> +static void setup_srchannel(pa_native_connection *c) {
> +    pa_srchannel_template srt;
> +    pa_srchannel *sr;
> +    pa_memchunk mc;
> +    pa_tagstruct *t;
> +    int fdlist[2];
> +
> +    if (c->version < 30) {
> +        pa_log_debug("Disabling srchannel, reason: Protocol too old");
> +        return;
> +    }
> +
> +    if (!c->protocol->core->rw_mempool) {
> +        pa_log_debug("Disabling srchannel, reason: No rw memory pool");
> +        return;
> +    }
> +
> +    pa_log_debug("Enabling srchannel...");
> +    sr = pa_srchannel_new(c->protocol->core->mainloop, c->protocol->core->rw_mempool);
> +    pa_srchannel_export(sr, &srt);
> +
> +    /* Allow client to access the memblock */
> +    mc.memblock = srt.memblock;
> +    mc.index = 0;
> +    mc.length = pa_memblock_get_length(srt.memblock);
> +    pa_pstream_send_memblock(c->pstream, 0, 0, 0, &mc);
> +
> +    /* Send enable command to client */
> +    t = pa_tagstruct_new(NULL, 0);
> +    pa_tagstruct_putu32(t, PA_COMMAND_ENABLE_RINGBUFFER);
> +    pa_tagstruct_putu32(t, (uint32_t) -1); /* tag */
> +    fdlist[0] = srt.readfd;
> +    fdlist[1] = srt.writefd;
> +    pa_pstream_send_tagstruct_with_fds(c->pstream, t, 2, fdlist);
> +
> +    /* ...and switch over */
> +    pa_pstream_set_srchannel(c->pstream, sr);

There seems to be no way for the client to refuse this, so we can never
stop supporting srchannel without breaking protocol compatibility.

-- 
Tanu