path: root/pat.c

/*
 * pat.c: PAT section filter
 *
 * See the main source file 'vdr.c' for copyright information and
 * how to reach the author.
 *
 * $Id: pat.c 1.3 2004/01/04 12:27:06 kls Exp $
 */

#include "pat.h"
#include <malloc.h>
#include "channels.h"
#include "libsi/section.h"
#include "libsi/descriptor.h"
#include "thread.h"

#define PMT_SCAN_TIMEOUT  10 // seconds

// --- cCaDescriptor ---------------------------------------------------------

class cCaDescriptor : public cListObject {
private:
  int caSystem;
  bool stream;
  int length;
  uchar *data;
public:
  cCaDescriptor(int CaSystem, int CaPid, bool Stream, int Length, const uchar *Data);
  virtual ~cCaDescriptor();
  bool operator== (const cCaDescriptor &arg) const;
  int CaSystem(void) { return caSystem; }
  int Stream(void) { return stream; }
  int Length(void) const { return length; }
  const uchar *Data(void) const { return data; }
  };

cCaDescriptor::cCaDescriptor(int CaSystem, int CaPid, bool Stream, int Length, const uchar *Data)
{
  caSystem = CaSystem;
  stream = Stream;
  length = Length + 6;
  data = MALLOC(uchar, length);
  data[0] = SI::CaDescriptorTag;
  data[1] = length - 2;
  data[2] = (caSystem >> 8) & 0xFF;
  data[3] =  caSystem       & 0xFF;
  data[4] = ((CaPid   >> 8) & 0x1F) | 0xE0;
  data[5] =   CaPid         & 0xFF;
  if (Length)
     memcpy(&data[6], Data, Length);
}

cCaDescriptor::~cCaDescriptor()
{
  free(data);
}

bool cCaDescriptor::operator== (const cCaDescriptor &arg) const
{
  return length == arg.length && memcmp(data, arg.data, length) == 0;
}

// --- cCaDescriptors --------------------------------------------------------

class cCaDescriptors : public cListObject {
private:
  int source;
  int transponder;
  int serviceId;
  int numCaIds;
  int caIds[MAXCAIDS + 1];
  cList<cCaDescriptor> caDescriptors;
  void AddCaId(int CaId);
public:
  cCaDescriptors(int Source, int Transponder, int ServiceId);
  bool operator== (const cCaDescriptors &arg) const;
  bool Is(int Source, int Transponder, int ServiceId);
  bool Is(cCaDescriptors * CaDescriptors);
  bool Empty(void) { return caDescriptors.Count() == 0; }
  void AddCaDescriptor(SI::CaDescriptor *d, bool Stream);
  int GetCaDescriptors(const unsigned short *CaSystemIds, int BufSize, uchar *Data, bool &StreamFlag);
  const int *CaIds(void) { return caIds; }
  };

cCaDescriptors::cCaDescriptors(int Source, int Transponder, int ServiceId)
{
  source = Source;
  transponder = Transponder;
  serviceId = ServiceId;
  numCaIds = 0;
  caIds[0] = 0;
}

bool cCaDescriptors::operator== (const cCaDescriptors &arg) const
{
  cCaDescriptor *ca1 = caDescriptors.First();
  cCaDescriptor *ca2 = arg.caDescriptors.First();
  while (ca1 && ca2) {
        if (!(*ca1 == *ca2))
           return false;
        ca1 = caDescriptors.Next(ca1);
        ca2 = arg.caDescriptors.Next(ca2);
        }
  return !ca1 && !ca2;
}

bool cCaDescriptors::Is(int Source, int Transponder, int ServiceId)
{
  return source == Source && transponder == Transponder && serviceId == ServiceId;
}

bool cCaDescriptors::Is(cCaDescriptors * CaDescriptors)
{
  return Is(CaDescriptors->source, CaDescriptors->transponder, CaDescriptors->serviceId);
}

void cCaDescriptors::AddCaId(int CaId)
{
  if (numCaIds < MAXCAIDS) {
     for (int i = 0; i < numCaIds; i++) {
         if (caIds[i] == CaId)
            return;
         }
     caIds[numCaIds++] = CaId;
     caIds[numCaIds] = 0;
     }
}

void cCaDescriptors::AddCaDescriptor(SI::CaDescriptor *d, bool Stream)
{
  cCaDescriptor *nca = new cCaDescriptor(d->getCaType(), d->getCaPid(), Stream, d->privateData.getLength(), d->privateData.getData());
  for (cCaDescriptor *ca = caDescriptors.First(); ca; ca = caDescriptors.Next(ca)) {
      if (*ca == *nca) {
         delete nca;
         return;
         }
      }
  AddCaId(nca->CaSystem());
  caDescriptors.Add(nca);
//#define DEBUG_CA_DESCRIPTORS 1
#ifdef DEBUG_CA_DESCRIPTORS
  char buffer[1024];
  char *q = buffer;
  q += sprintf(q, "CAM: %04X %5d %5d %04X %d -", source, transponder, serviceId, d->getCaType(), Stream);
  for (int i = 0; i < nca->Length(); i++)
      q += sprintf(q, " %02X", nca->Data()[i]);
  dsyslog(buffer);
#endif
}

int cCaDescriptors::GetCaDescriptors(const unsigned short *CaSystemIds, int BufSize, uchar *Data, bool &StreamFlag)
{
  if (!CaSystemIds || !*CaSystemIds)
     return 0;
  if (BufSize > 0 && Data) {
     int length = 0;
     int IsStream = -1;
     for (cCaDescriptor *d = caDescriptors.First(); d; d = caDescriptors.Next(d)) {
         const unsigned short *caids = CaSystemIds;
         do {
            if (d->CaSystem() == *caids) {
               if (length + d->Length() <= BufSize) {
                  if (IsStream >= 0 && IsStream != d->Stream())
                     dsyslog("CAM: different stream flag in CA descriptors");
                  IsStream = d->Stream();
                  memcpy(Data + length, d->Data(), d->Length());
                  length += d->Length();
                  }
               else
                  return -1;
               }
            } while (*++caids);
         }
     StreamFlag = IsStream == 1;
     return length;
     }
  return -1;
}

// --- cCaDescriptorHandler --------------------------------------------------

class cCaDescriptorHandler : public cList<cCaDescriptors> {
private:
  cMutex mutex;
public:
  int AddCaDescriptors(cCaDescriptors *CaDescriptors);
      // Returns 0 if this is an already known descriptor,
      // 1 if it is an all new descriptor with actual contents,
      // and 2 if an existing descriptor was changed.
  int GetCaDescriptors(int Source, int Transponder, int ServiceId, const unsigned short *CaSystemIds, int BufSize, uchar *Data, bool &StreamFlag);
  };

int cCaDescriptorHandler::AddCaDescriptors(cCaDescriptors *CaDescriptors)
{
  cMutexLock MutexLock(&mutex);
  for (cCaDescriptors *ca = First(); ca; ca = Next(ca)) {
      if (ca->Is(CaDescriptors)) {
         if (*ca == *CaDescriptors) {
            delete CaDescriptors;
            return 0;
            }
         Del(ca);
         Add(CaDescriptors);
         return 2;
         }
      }
  Add(CaDescriptors);
  return CaDescriptors->Empty() ? 0 : 1;
}

int cCaDescriptorHandler::GetCaDescriptors(int Source, int Transponder, int ServiceId, const unsigned short *CaSystemIds, int BufSize, uchar *Data, bool &StreamFlag)
{
  cMutexLock MutexLock(&mutex);
  for (cCaDescriptors *ca = First(); ca; ca = Next(ca)) {
      if (ca->Is(Source, Transponder, ServiceId))
         return ca->GetCaDescriptors(CaSystemIds, BufSize, Data, StreamFlag);
      }
  return 0;
}

cCaDescriptorHandler CaDescriptorHandler;

int GetCaDescriptors(int Source, int Transponder, int ServiceId, const unsigned short *CaSystemIds, int BufSize, uchar *Data, bool &StreamFlag)
{
  return CaDescriptorHandler.GetCaDescriptors(Source, Transponder, ServiceId, CaSystemIds, BufSize, Data, StreamFlag);
}

// --- cPatFilter ------------------------------------------------------------

cPatFilter::cPatFilter(void)
{
  pmtIndex = 0;
  pmtPid = 0;
  lastPmtScan = 0;
  numPmtEntries = 0;
  Set(0x00, 0x00);  // PAT
}

void cPatFilter::SetStatus(bool On)
{
  cFilter::SetStatus(On);
  pmtIndex = 0;
  pmtPid = 0;
  lastPmtScan = 0;
  numPmtEntries = 0;
}

void cPatFilter::Trigger(void)
{
  numPmtEntries = 0;
}

bool cPatFilter::PmtVersionChanged(int PmtPid, int Version)
{
  Version <<= 16;
  for (int i = 0; i < numPmtEntries; i++) {
      if ((pmtVersion[i] & 0x0000FFFF) == PmtPid) {
         bool Changed = (pmtVersion[i] & 0x00FF0000) != Version;
         if (Changed)
            pmtVersion[i] = PmtPid | Version;
         return Changed;
         }
      }
  if (numPmtEntries < MAXPMTENTRIES)
     pmtVersion[numPmtEntries++] = PmtPid | Version;
  return true;
}

void cPatFilter::Process(u_short Pid, u_char Tid, const u_char *Data, int Length)
{
  if (Pid == 0x00) {
     if (Tid == 0x00) {
        if (pmtPid && time(NULL) - lastPmtScan > PMT_SCAN_TIMEOUT) {
           Del(pmtPid, 0x02);
           pmtPid = 0;
           pmtIndex++;
           lastPmtScan = time(NULL);
           }
        if (!pmtPid) {
           SI::PAT pat(Data, false);
           if (!pat.CheckCRCAndParse())
              return;
           SI::PAT::Association assoc;
           int Index = 0;
           for (SI::Loop::Iterator it; pat.associationLoop.hasNext(it); ) {
               assoc = pat.associationLoop.getNext(it);
               if (!assoc.isNITPid()) {
                  if (Index++ == pmtIndex) {
                     pmtPid = assoc.getPid();
                     Add(pmtPid, 0x02);
                     break;
                     }
                  }
               }
           if (!pmtPid)
              pmtIndex = 0;
           }
        }
     }
  else if (Pid == pmtPid && Tid == SI::TableIdPMT && Source() && Transponder()) {
     SI::PMT pmt(Data, false);
     if (!pmt.CheckCRCAndParse())
        return;
     if (!PmtVersionChanged(pmtPid, pmt.getVersionNumber())) {
        lastPmtScan = 0; // this triggers the next scan
        return;
        }
     if (!Channels.Lock(true, 10)) {
        numPmtEntries = 0; // to make sure we try again
        return;
        }
     cChannel *Channel = Channels.GetByServiceID(Source(), Transponder(), pmt.getServiceId());
     if (Channel) {
        SI::CaDescriptor *d;
        cCaDescriptors *CaDescriptors = new cCaDescriptors(Channel->Source(), Channel->Transponder(), Channel->Sid());
        // Scan the common loop:
        for (SI::Loop::Iterator it; (d = (SI::CaDescriptor*)pmt.commonDescriptors.getNext(it, SI::CaDescriptorTag)); ) {
            CaDescriptors->AddCaDescriptor(d, false);
            delete d;
            }
        // Scan the stream-specific loop:
        SI::PMT::Stream stream;
        int Vpid = 0;
        int Ppid = pmt.getPCRPid();
        int Apids[MAXAPIDS] = { 0 };
        int Dpids[MAXAPIDS] = { 0 };
        int Tpid = 0;
        int NumApids = 0;
        int NumDpids = 0;
        for (SI::Loop::Iterator it; pmt.streamLoop.hasNext(it); ) {
            stream = pmt.streamLoop.getNext(it);
            switch (stream.getStreamType()) {
              case 1: // STREAMTYPE_11172_VIDEO
              case 2: // STREAMTYPE_13818_VIDEO
                      Vpid = stream.getPid();
                      break;
              case 3: // STREAMTYPE_11172_AUDIO
              case 4: // STREAMTYPE_13818_AUDIO
                      {
                      if (NumApids < MAXAPIDS)
                         Apids[NumApids++] = stream.getPid();
                      }
                      break;
              case 5: // STREAMTYPE_13818_PRIVATE
              case 6: // STREAMTYPE_13818_PES_PRIVATE
              //XXX case 8: // STREAMTYPE_13818_DSMCC
                      {
                      SI::Descriptor *d;
                      for (SI::Loop::Iterator it; (d = stream.streamDescriptors.getNext(it)); ) {
                          switch (d->getDescriptorTag()) {
                            case SI::AC3DescriptorTag:
                                 if (NumDpids < MAXAPIDS)
                                    Dpids[NumDpids++] = stream.getPid();
                                 break;
                            case SI::TeletextDescriptorTag:
                                 Tpid = stream.getPid();
                                 break;
                            default: ;
                            }
                          delete d;
                          }
                      }
                      break;
              //default: printf("PID: %5d %5d %2d %3d %3d\n", pmt.getServiceId(), stream.getPid(), stream.getStreamType(), pmt.getVersionNumber(), Channel->Number());//XXX
              }
            for (SI::Loop::Iterator it; (d = (SI::CaDescriptor*)stream.streamDescriptors.getNext(it, SI::CaDescriptorTag)); ) {
                CaDescriptors->AddCaDescriptor(d, true);
                delete d;
                }
            }
        Channel->SetPids(Vpid, Ppid, Apids[0], Apids[1], Dpids[0], Dpids[1], Tpid);
        Channel->SetCaIds(CaDescriptors->CaIds());
        Channel->SetCaDescriptors(CaDescriptorHandler.AddCaDescriptors(CaDescriptors));
        }
     lastPmtScan = 0; // this triggers the next scan
     Channels.Unlock();
     }
}