bool CPatParser::GetChannel(int index, CChannelInfo& info)
{
static CChannelInfo unknownChannel;
if (index < 0 || index > Count())
{
return false;
}
CPmtParser* parser = m_pmtParsers[index];
if (false == parser->IsReady())
{
return false;
}
info.PidTable = parser->GetPidInfo();
m_iState = Idle;
return true;
}
void CPmtGrabber::OnNewSection(CSection& section)
{
try
{
// if only service ID given, lookup from PAT
if (GetPid() == 0) // PID 0 is the PAT, so look for matching PMT
{
int PMTPid=m_patgrab.PATRequest(section, m_iServiceId);
if (PMTPid>0)
{
SetPmtPid(PMTPid,m_iServiceId);
SetPid(PMTPid);
}
else
{
LogDebug("PMT Pid wasn't found on the PAT. Channel may have moved, try a new channel scan.");
}
}
if (section.table_id!=2) return;
CEnterCriticalSection enter(m_section);
if (section.section_length<0 || section.section_length>=MAX_SECTION_LENGTH) return;
long serviceId = section.table_id_extension;
if (m_iPmtVersion<0)
LogDebug("pmtgrabber: got pmt %x sid:%x",GetPid(), serviceId);
if (serviceId != m_iServiceId)
{
LogDebug("pmtgrabber: serviceid mismatch %x != %x",serviceId,m_iServiceId);
return;
}
m_iPmtLength=section.section_length;
// copy pmt data for passing it to tvserver
memcpy(m_pmtData,section.Data,m_iPmtLength);
// compare the current section data with the previous one
if (memcmp(section.Data, m_pmtPrevSection.Data, m_iPmtLength)!=0)
{
bool pidsChanged = false;
CPmtParser prevPmtParser;
CPmtParser currPmtParser;
prevPmtParser.SetPid(GetPid());
prevPmtParser.DecodePmtPidTable(m_pmtPrevSection);
currPmtParser.SetPid(GetPid());
// Check if failed - if corrupted it can crash tv service after the callback
if(!currPmtParser.DecodePmtPidTable(section))
{
LogDebug("CPmtGrabber::OnNewSection() - Error decoding PMT from new section, bad signal?");
return;
}
if (!(prevPmtParser.GetPidInfo() == currPmtParser.GetPidInfo()))
{
LogDebug("pmtgrabber: PMT pids changed from:");
prevPmtParser.GetPidInfo().LogPIDs();
LogDebug("pmtgrabber: PMT pids changed to:");
currPmtParser.GetPidInfo().LogPIDs();
pidsChanged = true;
}
m_pmtPrevSection=section;
// do a callback each time the version number changes. this also allows switching for "regional channels"
if (m_pCallback!=NULL && m_iPmtVersion != section.version_number)
{
LogDebug("pmtgrabber: got new pmt version:%x %x, service_id:%x", section.version_number, m_iPmtVersion, serviceId);
// if the pids are different, then a callback is required.
if (pidsChanged)
{
LogDebug("pmtgrabber: do callback pid %x",GetPid());
m_pCallback->OnPMTReceived(GetPid());
}
// otherwise no need to callback, i.e. if _only_ version number changes regulary...
else
{
LogDebug("pmtgrabber: NO callback done because a/v pids still the same.");
}
}
}
m_iPmtVersion=section.version_number;
}
catch(...)
{
LogDebug("CPmtGrabber::OnNewSection exception");
}
}