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DATV: leandvb: retrofit of S2 deframer: Set TEI bit on TS packets with bad CRC8.

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This commit is contained in:
f4exb 2021-03-26 02:17:38 +01:00
parent 3bfa552813
commit 8a36adaeea
1 changed files with 44 additions and 38 deletions
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78
plugins/channelrx/demoddatv/leansdr/dvbs2.h
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@ -28,6 +28,8 @@
// skip Soft-decoding of S2 PLSCODE. pabr committed on Jan 16, 2020
// skip Validate PLHEADER soft-decoding when DEBUG_CARRIER==1. pabr committed on Jan 17, 2020
// | Cleanup scope of some S2 constants. pabr committed on Apr 29, 2020
// skip Fix overflow to state_out stream. pabr committed on Apr 29, 2020
// | S2 deframer: Set TEI bit on TS packets with bad CRC8. pabr committed on Jul 29, 2020
#ifndef LEANSDR_DVBS2_H
#define LEANSDR_DVBS2_H
@ -3709,7 +3711,7 @@ struct s2_deframer : runnable
) :
runnable(sch, "S2 deframer"),
fd_gse(-1),
missing(-1),
nleftover(-1),
in(_in),
out(_out, MAX_TS_PER_BBFRAME),
current_state(false),
@ -3788,18 +3790,18 @@ private:
fprintf(stderr, "Bad bbframe\n");
}
missing = -1;
nleftover = -1;
info_unlocked();
return;
return; // Max one state_out per loop
}
// TBD: Supporting byte-oriented payloads only.
if ((dfl&7) || (syncd&7))
{
fprintf(stderr, "Unsupported bbframe\n");
missing = -1;
nleftover = -1;
info_unlocked();
return;
return; // Max one state_out per loop
}
if (streamtype==3 && upl==188*8 && sync==0x47 && syncd<=dfl)
@ -3829,68 +3831,70 @@ private:
void handle_ts(uint8_t *data, uint16_t dfl, uint16_t syncd, uint8_t sync)
{
// TBD Handle packets as payload+finalCRC and do crc8 before pout
int pos; // Start of useful data in this bbframe
if (missing < 0)
if (nleftover < 0)
{
// Skip unusable data at beginning of bbframe
// Not synced. Skip unusable data at beginning of bbframe
pos = syncd / 8;
if (sch->debug) {
fprintf(stderr, "Start TS at %d\n", pos);
}
missing = 0;
nleftover = 0;
}
else
{
// Sanity check
if (syncd / 8 != missing)
if (syncd / 8 != 188 - nleftover)
{
if (sch->debug) {
fprintf(stderr, "Lost a bbframe ?\n");
}
missing = -1;
nleftover = -1;
info_unlocked();
return;
return; // Max one state_out per loop
}
pos = 0;
}
if (missing)
while ( pos+(188-nleftover)+1 <= dfl/8 )
{
// Complete and output the partial TS packet in leftover[].
// Enough data available for one packet and its CRC.
tspacket *pout = out.wr();
memcpy(pout->data, leftover, 188 - missing);
memcpy(pout->data + (188 - missing), data + pos, missing);
out.written(1);
memcpy(pout->data, leftover, nleftover); // NOP most of the time
memcpy(pout->data+nleftover, data+pos, 188-nleftover);
pout->data[0] = sync; // Replace CRC
uint8_t crc = crc8.compute(pout->data+1, 188-1);
if (data[pos+(188-nleftover)] == crc)
{
info_good_packet();
++pout;
// Skip to beginning of next TS packet
pos += missing;
missing = 0;
}
else
{
pout->data[1] |= 0x80; // Set TEI bit
if (sch->debug) {
fprintf(stderr, "C");
}
}
while (pos + 188 <= dfl / 8)
{
tspacket *pout = out.wr();
memcpy(pout->data, data + pos, 188);
pout->data[0] = sync; // Replace CRC
out.written(1);
info_good_packet();
pos += 188;
pos += 188 - nleftover;
nleftover = 0;
}
int remain = dfl / 8 - pos;
if (remain)
{
memcpy(leftover, data + pos, remain);
leftover[0] = sync; // Replace CRC
missing = 188 - remain;
if (nleftover + remain > (int) sizeof(leftover)) {
fail("Bug: TS deframer");
}
memcpy(leftover+nleftover, data+pos, remain);
nleftover += remain;
}
void info_unlocked()
@ -3916,9 +3920,11 @@ private:
}
crc8_engine crc8;
int missing; // Bytes needed to complete leftover[],
// or 0 if no leftover data,
// or -1 if not synced.
int nleftover; // Bytes in leftover[]:
// -1 = not synced.
// 0 = no leftover data
// 1 - 187 = incomplete packet
// 188 = waiting for CRC
uint8_t leftover[188];
static const int MAX_TS_PER_BBFRAME = fec_info::KBCH_MAX / 8 / 188 + 1;
bool locked;