pulseaudio/src/pulsecore/pdispatch.h
Ahmed S. Darwish 27d0a3b388 pstream: Support memfd blocks transport
Now that we have the necessary infrastructure to memexport and
mempimport a memfd memblock, extend that support higher up in the
chain with pstreams.

A PA endpoint can now _transparently_ send a memfd memblock to the
other end by simply calling pa_pstream_send_memblock() – provided
the block's memfd pool was earlier registered with the pstream.

If the pipe does not support memfd transfers, we fall back to
sending the block's full data instead of just its reference.

** Further details:

A single pstream connection usually transfers blocks from multiple
pools including the server's srbchannel mempool, the client's
audio data mempool, and the server's global core mempool.

If these mempools are memfd-backed, we now require registering
them with the pstream before sending any blocks they cover. This
is done to minimize fd passing overhead and avoid fd leaks.

Moreover, to support all these pools without hard-coding their
number or nature in the Pulse communication protocol itself, a new
REGISTER_MEMFD_SHMID command is introduced. That command can be
sent _anytime_ during the pstream's lifetime and is used for
creating on demand SHM ID to memfd mappings.

Suggested-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
2016-04-02 05:55:14 +02:00

56 lines
2.1 KiB
C

#ifndef foopdispatchhfoo
#define foopdispatchhfoo
/***
This file is part of PulseAudio.
Copyright 2004-2006 Lennart Poettering
Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
PulseAudio is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
PulseAudio is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
***/
#include <inttypes.h>
#include <pulse/mainloop-api.h>
#include <pulse/def.h>
#include <pulsecore/tagstruct.h>
#include <pulsecore/packet.h>
#include <pulsecore/creds.h>
typedef struct pa_pdispatch pa_pdispatch;
typedef void (*pa_pdispatch_cb_t)(pa_pdispatch *pd, uint32_t command, uint32_t tag, pa_tagstruct *t, void *userdata);
typedef void (*pa_pdispatch_drain_cb_t)(pa_pdispatch *pd, void *userdata);
pa_pdispatch* pa_pdispatch_new(pa_mainloop_api *m, bool use_rtclock, const pa_pdispatch_cb_t *table, unsigned entries);
void pa_pdispatch_unref(pa_pdispatch *pd);
pa_pdispatch* pa_pdispatch_ref(pa_pdispatch *pd);
int pa_pdispatch_run(pa_pdispatch *pd, pa_packet *p, pa_cmsg_ancil_data *ancil_data, void *userdata);
void pa_pdispatch_register_reply(pa_pdispatch *pd, uint32_t tag, int timeout, pa_pdispatch_cb_t callback, void *userdata, pa_free_cb_t free_cb);
int pa_pdispatch_is_pending(pa_pdispatch *pd);
void pa_pdispatch_set_drain_callback(pa_pdispatch *pd, pa_pdispatch_drain_cb_t callback, void *userdata);
/* Remove all reply slots with the give userdata parameter */
void pa_pdispatch_unregister_reply(pa_pdispatch *pd, void *userdata);
const pa_creds * pa_pdispatch_creds(pa_pdispatch *pd);
pa_cmsg_ancil_data *pa_pdispatch_take_ancil_data(pa_pdispatch *pd);
#endif