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|
/* $NetBSD: dtv_demux.c,v 1.11 2020/05/30 13:15:10 jdolecek Exp $ */
/*-
* Copyright (c) 2011 Jared D. McNeill <jmcneill@invisible.ca>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Jared D. McNeill.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* This file contains support for the /dev/dvb/adapter<n>/demux0 device.
*
* The demux device is implemented as a cloning device. Each instance can
* be in one of three modes: unconfigured (NONE), section filter (SECTION),
* or PID filter (PES).
*
* An instance in section filter mode extracts PSI sections based on a
* filter configured by the DMX_SET_FILTER ioctl. When an entire section is
* received, it is made available to userspace via read method. Data is fed
* into the section filter using the dtv_demux_write function.
*
* An instance in PID filter mode extracts TS packets that match the
* specified PID filter configured by the DMX_SET_PES_FILTER, DMX_ADD_PID,
* and DMX_REMOVE_PID ioctls. As this driver only implements the
* DMX_OUT_TS_TAP output, these TS packets are made available to userspace
* by calling read on the /dev/dvb/adapter<n>/dvr0 device.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: dtv_demux.c,v 1.11 2020/05/30 13:15:10 jdolecek Exp $");
#include <sys/param.h>
#include <sys/types.h>
#include <sys/conf.h>
#include <sys/kmem.h>
#include <sys/device.h>
#include <sys/select.h>
#include <sys/filedesc.h>
#include <sys/file.h>
#include <sys/poll.h>
#include <sys/vnode.h>
#include <sys/queue.h>
#include <dev/dtv/dtvvar.h>
static int dtv_demux_read(struct file *, off_t *, struct uio *,
kauth_cred_t, int);
static int dtv_demux_ioctl(struct file *, u_long, void *);
static int dtv_demux_poll(struct file *, int);
static int dtv_demux_close(struct file *);
static const struct fileops dtv_demux_fileops = {
.fo_name = "dtv_demux",
.fo_read = dtv_demux_read,
.fo_write = fbadop_write,
.fo_ioctl = dtv_demux_ioctl,
.fo_fcntl = fnullop_fcntl,
.fo_poll = dtv_demux_poll,
.fo_stat = fbadop_stat,
.fo_close = dtv_demux_close,
.fo_kqfilter = fnullop_kqfilter,
.fo_restart = fnullop_restart,
};
static uint32_t crc_table[256] = {
0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9,
0x130476dc, 0x17c56b6b, 0x1a864db2, 0x1e475005,
0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd,
0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9,
0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011,
0x791d4014, 0x7ddc5da3, 0x709f7b7a, 0x745e66cd,
0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5,
0xbe2b5b58, 0xbaea46ef, 0xb7a96036, 0xb3687d81,
0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49,
0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95,
0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d,
0x34867077, 0x30476dc0, 0x3d044b19, 0x39c556ae,
0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16,
0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca,
0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02,
0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1, 0x53dc6066,
0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e,
0xbfa1b04b, 0xbb60adfc, 0xb6238b25, 0xb2e29692,
0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a,
0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e,
0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686,
0xd5b88683, 0xd1799b34, 0xdc3abded, 0xd8fba05a,
0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb,
0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f,
0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47,
0x36194d42, 0x32d850f5, 0x3f9b762c, 0x3b5a6b9b,
0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623,
0xf12f560e, 0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7,
0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f,
0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3,
0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b,
0x9b3660c6, 0x9ff77d71, 0x92b45ba8, 0x9675461f,
0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640,
0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c,
0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24,
0x119b4be9, 0x155a565e, 0x18197087, 0x1cd86d30,
0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088,
0x2497d08d, 0x2056cd3a, 0x2d15ebe3, 0x29d4f654,
0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c,
0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18,
0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0,
0x9abc8bd5, 0x9e7d9662, 0x933eb0bb, 0x97ffad0c,
0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
};
/* ISO/IEC 13818-1 Annex A "CRC Decoder Model" */
static uint32_t
dtv_demux_crc32(uint8_t *buf, int len)
{
const uint32_t *crc_tab = crc_table;
uint32_t CRC = 0xffffffff;
int i;
for (i = 0; i < len; i++)
CRC = (CRC << 8) ^ crc_tab[((CRC >> 24) ^ *buf++) & 0xff];
return CRC;
}
/*
* Start running the demux.
*/
static int
dtv_demux_start(struct dtv_demux *demux)
{
struct dtv_softc *sc = demux->dd_sc;
int error = 0;
bool dostart = false;
/*
* If the demux is not running, mark it as running and update the
* global demux run counter.
*/
mutex_enter(&sc->sc_lock);
KASSERT(sc->sc_demux_runcnt >= 0);
if (demux->dd_running == false) {
sc->sc_demux_runcnt++;
demux->dd_running = true;
/* If this is the first demux running, trigger device start */
dostart = sc->sc_demux_runcnt == 1;
}
mutex_exit(&sc->sc_lock);
if (dostart) {
/* Setup receive buffers and trigger device start */
error = dtv_buffer_setup(sc);
if (error == 0)
error = dtv_device_start_transfer(sc);
}
/*
* If something went wrong, restore the run counter and mark this
* demux instance as halted.
*/
if (error) {
mutex_enter(&sc->sc_lock);
sc->sc_demux_runcnt--;
demux->dd_running = false;
mutex_exit(&sc->sc_lock);
}
return error;
}
/*
* Stop running the demux.
*/
static int
dtv_demux_stop(struct dtv_demux *demux)
{
struct dtv_softc *sc = demux->dd_sc;
int error = 0;
bool dostop = false;
/*
* If the demux is running, mark it as halted and update the
* global demux run counter.
*/
mutex_enter(&sc->sc_lock);
if (demux->dd_running == true) {
KASSERT(sc->sc_demux_runcnt > 0);
demux->dd_running = false;
sc->sc_demux_runcnt--;
/* If this was the last demux running, trigger device stop */
dostop = sc->sc_demux_runcnt == 0;
}
mutex_exit(&sc->sc_lock);
if (dostop) {
/* Trigger device stop */
error = dtv_device_stop_transfer(sc);
}
/*
* If something went wrong, restore the run counter and mark this
* demux instance as running.
*/
if (error) {
mutex_enter(&sc->sc_lock);
sc->sc_demux_runcnt++;
demux->dd_running = true;
mutex_exit(&sc->sc_lock);
}
return error;
}
/*
* Put the demux into PID filter mode and update the PID filter table.
*/
static int
dtv_demux_set_pidfilter(struct dtv_demux *demux, uint16_t pid, bool onoff)
{
struct dtv_softc *sc = demux->dd_sc;
/*
* TS PID is 13 bits; demux device uses special PID 0x2000 to mean
* "all PIDs". Verify that the requested PID is in range.
*/
if (pid > 0x2000)
return EINVAL;
/* Set demux mode */
demux->dd_mode = DTV_DEMUX_MODE_PES;
/*
* If requesting "all PIDs", set the on/off flag for all PIDs in
* the PID map, otherwise set the on/off flag for the requested
* PID.
*/
if (pid == 0x2000) {
memset(sc->sc_ts.ts_pidfilter, onoff ? 0xff : 0,
sizeof(sc->sc_ts.ts_pidfilter));
} else {
sc->sc_ts.ts_pidfilter[pid] = onoff;
}
return 0;
}
/*
* Open a new instance of the demux cloning device.
*/
int
dtv_demux_open(struct dtv_softc *sc, int flags, int mode, lwp_t *l)
{
struct file *fp;
struct dtv_demux *demux;
int error, fd;
/* Allocate private storage */
demux = kmem_zalloc(sizeof(*demux), KM_SLEEP);
demux->dd_sc = sc;
/* Default operation mode is unconfigured */
demux->dd_mode = DTV_DEMUX_MODE_NONE;
selinit(&demux->dd_sel);
mutex_init(&demux->dd_lock, MUTEX_DEFAULT, IPL_SCHED);
cv_init(&demux->dd_section_cv, "dtvsec");
error = fd_allocfile(&fp, &fd);
if (error) {
kmem_free(demux, sizeof(*demux));
return error;
}
/* Add the demux to the list of demux instances */
mutex_enter(&sc->sc_demux_lock);
TAILQ_INSERT_TAIL(&sc->sc_demux_list, demux, dd_entries);
mutex_exit(&sc->sc_demux_lock);
return fd_clone(fp, fd, flags, &dtv_demux_fileops, demux);
}
/*
* Close the instance of the demux cloning device.
*/
int
dtv_demux_close(struct file *fp)
{
struct dtv_demux *demux = fp->f_data;
struct dtv_softc *sc;
int error;
if (demux == NULL)
return ENXIO;
fp->f_data = NULL;
sc = demux->dd_sc;
/* If the demux is still running, stop it */
if (demux->dd_running) {
error = dtv_demux_stop(demux);
if (error)
return error;
}
/* Remove the demux from the list of demux instances */
mutex_enter(&sc->sc_demux_lock);
TAILQ_REMOVE(&sc->sc_demux_list, demux, dd_entries);
mutex_exit(&sc->sc_demux_lock);
mutex_destroy(&demux->dd_lock);
cv_destroy(&demux->dd_section_cv);
kmem_free(demux, sizeof(*demux));
/* Update the global device open count */
dtv_common_close(sc);
return 0;
}
/*
* Handle demux ioctl requests
*/
static int
dtv_demux_ioctl(struct file *fp, u_long cmd, void *data)
{
struct dtv_demux *demux = fp->f_data;
struct dmx_pes_filter_params *pesfilt;
struct dmx_sct_filter_params *sctfilt;
uint16_t pid;
int error;
if (demux == NULL)
return ENXIO;
switch (cmd) {
case DMX_START:
return dtv_demux_start(demux);
case DMX_STOP:
return dtv_demux_stop(demux);
case DMX_SET_BUFFER_SIZE:
/*
* The demux driver doesn't support configurable buffer sizes,
* but software relies on this command succeeding.
*/
return 0;
case DMX_SET_FILTER:
sctfilt = data;
/* Verify that the requested PID is in range. */
if (sctfilt->pid >= 0x2000)
return EINVAL;
/*
* Update section filter parameters, reset read/write ptrs,
* clear section count and overflow flag, and set the
* demux instance mode to section filter.
*/
demux->dd_secfilt.params = *sctfilt;
demux->dd_secfilt.rp = demux->dd_secfilt.wp = 0;
demux->dd_secfilt.nsections = 0;
demux->dd_secfilt.overflow = false;
demux->dd_mode = DTV_DEMUX_MODE_SECTION;
/*
* If the DMX_IMMEDIATE_START flag is present in the request,
* start running the demux immediately (no need for a
* subsequent DMX_START ioctl).
*/
if (sctfilt->flags & DMX_IMMEDIATE_START) {
error = dtv_demux_start(demux);
if (error)
return error;
}
return 0;
case DMX_SET_PES_FILTER:
pesfilt = data;
/* The driver only supports input from the frontend */
if (pesfilt->input != DMX_IN_FRONTEND)
return EINVAL;
/*
* The driver only supports output to the TS TAP in PID
* filter mode.
*/
if (pesfilt->output != DMX_OUT_TS_TAP)
return EINVAL;
/* Update PID filter table */
error = dtv_demux_set_pidfilter(demux, pesfilt->pid, true);
if (error)
return error;
/*
* If the DMX_IMMEDIATE_START flag is present in the request,
* start running the demux immediately (no need for a
* subsequent DMX_START ioctl).
*/
if (pesfilt->flags & DMX_IMMEDIATE_START) {
error = dtv_demux_start(demux);
if (error)
return error;
}
return 0;
case DMX_ADD_PID:
pid = *(uint16_t *)data;
return dtv_demux_set_pidfilter(demux, pid, true);
case DMX_REMOVE_PID:
pid = *(uint16_t *)data;
return dtv_demux_set_pidfilter(demux, pid, false);
default:
return EINVAL;
}
}
/*
* Test for I/O readiness
*/
static int
dtv_demux_poll(struct file *fp, int events)
{
struct dtv_demux *demux = fp->f_data;
int revents = 0;
if (demux == NULL)
return POLLERR;
/*
* If the demux instance is in section filter mode, wait for an
* entire section to become ready.
*/
mutex_enter(&demux->dd_lock);
if (demux->dd_mode == DTV_DEMUX_MODE_SECTION &&
demux->dd_secfilt.nsections > 0) {
revents |= POLLIN;
} else {
selrecord(curlwp, &demux->dd_sel);
}
mutex_exit(&demux->dd_lock);
return revents;
}
/*
* Read from the demux instance
*/
static int
dtv_demux_read(struct file *fp, off_t *offp, struct uio *uio,
kauth_cred_t cred, int flags)
{
struct dtv_demux *demux = fp->f_data;
struct dtv_ts_section *sec;
int error;
if (demux == NULL)
return ENXIO;
/* Only support read if the instance is in section filter mode */
if (demux->dd_mode != DTV_DEMUX_MODE_SECTION)
return EIO;
sec = kmem_alloc(sizeof(*sec), KM_SLEEP);
/* Wait for a complete PSI section */
mutex_enter(&demux->dd_lock);
while (demux->dd_secfilt.nsections == 0) {
if (flags & IO_NDELAY) {
mutex_exit(&demux->dd_lock);
/* No data available */
error = EWOULDBLOCK;
goto out;
}
error = cv_wait_sig(&demux->dd_section_cv, &demux->dd_lock);
if (error) {
mutex_exit(&demux->dd_lock);
goto out;
}
}
/* Copy the completed PSI section */
*sec = demux->dd_secfilt.section[demux->dd_secfilt.rp];
/* Update read pointer */
demux->dd_secfilt.rp++;
if (demux->dd_secfilt.rp >= __arraycount(demux->dd_secfilt.section))
demux->dd_secfilt.rp = 0;
/* Update section count */
demux->dd_secfilt.nsections--;
mutex_exit(&demux->dd_lock);
/*
* If the filter parameters specify the DMX_ONESHOT flag, stop
* the demux after one PSI section is received.
*/
if (demux->dd_secfilt.params.flags & DMX_ONESHOT)
dtv_demux_stop(demux);
/*
* Copy the PSI section to userspace. If the receiving buffer is
* too small, the rest of the payload will be discarded. Although
* this behaviour differs from the Linux implementation, in practice
* it should not be an issue as PSI sections have a max size of 4KB
* (and callers will generally provide a big enough buffer).
*/
error = uiomove(sec->sec_buf, sec->sec_length, uio);
out:
kmem_free(sec, sizeof(*sec));
return error;
}
/*
* Verify the CRC of a PSI section.
*/
static bool
dtv_demux_check_crc(struct dtv_demux *demux, struct dtv_ts_section *sec)
{
uint32_t crc, sec_crc;
/*
* If section_syntax_indicator is not set, the PSI section does
* not include a CRC field.
*/
if ((sec->sec_buf[1] & 0x80) == 0)
return false;
sec_crc = be32dec(&sec->sec_buf[sec->sec_length - 4]);
crc = dtv_demux_crc32(&sec->sec_buf[0], sec->sec_length - 4);
return crc == sec_crc;
}
/*
* Process a single TS packet and extract PSI sections based on the
* instance's section filter.
*/
static int
dtv_demux_process(struct dtv_demux *demux, const uint8_t *tspkt,
size_t tspktlen)
{
struct dtv_ts_section *sec;
dmx_filter_t *dmxfilt = &demux->dd_secfilt.params.filter;
const uint8_t *p;
uint16_t section_length;
int brem, avail;
KASSERT(tspktlen == TS_PKTLEN);
/* If the demux instance is not running, ignore the packet */
if (demux->dd_running == false)
return 0;
/*
* If the demux instance is not in section filter mode, ignore
* the packet
*/
if (demux->dd_mode != DTV_DEMUX_MODE_SECTION)
return 0;
/*
* If the packet's TS PID does not match the section filter PID,
* ignore the packet
*/
if (TS_PID(tspkt) != demux->dd_secfilt.params.pid)
return 0;
/*
* If the TS packet does not contain a payload, ignore the packet
*/
if (TS_HAS_PAYLOAD(tspkt) == 0)
return 0;
mutex_enter(&demux->dd_lock);
/* If the section buffer is full, set the overflow flag and return */
if (demux->dd_secfilt.nsections ==
__arraycount(demux->dd_secfilt.section)) {
demux->dd_secfilt.overflow = true;
goto done;
}
sec = &demux->dd_secfilt.section[demux->dd_secfilt.wp];
/* If we have no bytes in our buffer, wait for payload unit start */
if (sec->sec_bytesused == 0 && TS_HAS_PUSI(tspkt) == 0)
goto done;
/* find payload start */
p = tspkt + 4;
if (TS_HAS_AF(tspkt)) {
if (*p > 182) /* AF length with payload is between 0-182 */
goto done;
p += (1 + *p);
}
if (TS_HAS_PUSI(tspkt)) {
p += (1 + *p);
}
brem = tspktlen - (p - tspkt);
if (TS_HAS_PUSI(tspkt)) {
if (brem < 16)
goto done;
section_length = ((p[1] & 0xf) << 8) | p[2];
/* table_id filter */
if (dmxfilt->mask[0]) {
if ((p[0] & dmxfilt->mask[0]) != dmxfilt->filter[0])
goto done;
}
/* table_id_ext filter */
if (dmxfilt->mask[1] && dmxfilt->mask[2]) {
/*
* table_id_ext is only valid if
* section_syntax_indicator is set
*/
if (section_length < 2 || (p[1] & 0x80) == 0)
goto done;
if ((p[3] & dmxfilt->mask[1]) != dmxfilt->filter[1])
goto done;
if ((p[4] & dmxfilt->mask[2]) != dmxfilt->filter[2])
goto done;
}
sec->sec_length = section_length + 3;
/* maximum section length is 4KB */
if (sec->sec_length > sizeof(sec->sec_buf)) {
sec->sec_bytesused = sec->sec_length = 0;
goto done;
}
}
/* If we have bytes pending and we see payload unit start, flush buf */
if (sec->sec_bytesused > 0 && TS_HAS_PUSI(tspkt))
sec->sec_bytesused = sec->sec_length = 0;
/* Copy data into section buffer */
avail = uimin(sec->sec_length - sec->sec_bytesused, brem);
if (avail < 0)
goto done;
memcpy(&sec->sec_buf[sec->sec_bytesused], p, avail);
sec->sec_bytesused += avail;
/*
* If a complete section has been received, update section count
* and notify readers.
*/
if (sec->sec_bytesused == sec->sec_length) {
/*
* If the DMX_CHECK_CRC flag was present in the DMX_SET_FILTER
* parameters, verify the PSI section checksum. If the
* checksum is invalid, discard the entire corrupt section.
*/
if ((demux->dd_secfilt.params.flags & DMX_CHECK_CRC) &&
dtv_demux_check_crc(demux, sec) == false) {
/* discard section */
sec->sec_bytesused = sec->sec_length = 0;
goto done;
}
demux->dd_secfilt.wp++;
if (demux->dd_secfilt.wp >=
__arraycount(demux->dd_secfilt.section))
demux->dd_secfilt.wp = 0;
demux->dd_secfilt.nsections++;
cv_broadcast(&demux->dd_section_cv);
selnotify(&demux->dd_sel, 0, 0);
}
done:
mutex_exit(&demux->dd_lock);
return 0;
}
/*
* Submit TS data to all demux instances
*/
void
dtv_demux_write(struct dtv_softc *sc, const uint8_t *tspkt, size_t tspktlen)
{
struct dtv_demux *demux;
mutex_enter(&sc->sc_demux_lock);
TAILQ_FOREACH(demux, &sc->sc_demux_list, dd_entries) {
dtv_demux_process(demux, tspkt, tspktlen);
}
mutex_exit(&sc->sc_demux_lock);
}
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