Improved cSectionSyncer

HISTORY

@@ -9578,7 +9578,7 @@ Video Disk Recorder Revision History
   given (reported by Manuel Reimer).
 - Fixed handling $(PKG_CONFIG) in newplugin (thanks to Winfried Köhler).
 
-2021-01-19:
+2021-03-16:
 
 - Fixed strreplace() to handle NULL strings (reported by Jürgen Schneider).
 - Somewhere down the road the 'x' bit of Doxyfile.filter got lost, so the
@@ -9605,3 +9605,9 @@ Video Disk Recorder Revision History
   Jürgen Schneider).
 - Added some missing user command calls for copying, renaming and moving recordings
   (thanks to Peter Bieringer).
+- Improved cSectionSyncer to make sure that no sections are missed, and to allow
+  handling partially used segments (as in the EIT) and processing sections in random
+  order. Segment syncing is now done with the two member functions Check() and
+  Processed(). The old functions Sync() and Repeat() are deprecated and may be
+  removed in a future version. See the comments in filter.h for a description on
+  how to use these new function.

eit.c

@@ -8,7 +8,7 @@
  * Robert Schneider <Robert.Schneider@web.de> and Rolf Hakenes <hakenes@hippomi.de>.
  * Adapted to 'libsi' for VDR 1.3.0 by Marcel Wiesweg <marcel.wiesweg@gmx.de>.
  *
- * $Id: eit.c 4.11 2020/11/28 21:45:05 kls Exp $
+ * $Id: eit.c 5.1 2021/03/16 15:10:54 kls Exp $
  */
 
 #include "eit.h"
@@ -22,6 +22,28 @@
 
 #define DBGEIT 0
 
+// --- cEitTables ------------------------------------------------------------
+
+bool cEitTables::Check(uchar TableId, uchar Version, int SectionNumber)
+{
+  int ti = Index(TableId);
+  return sectionSyncer[ti].Check(Version, SectionNumber);
+}
+
+bool cEitTables::Processed(uchar TableId, uchar LastTableId, int SectionNumber, int LastSectionNumber, int SegmentLastSectionNumber)
+{
+  int ti = Index(TableId);
+  int LastIndex = Index(LastTableId);
+  if (sectionSyncer[ti].Processed(SectionNumber, LastSectionNumber, SegmentLastSectionNumber)) {
+     for (int i = 0; i <= LastIndex; i++) {
+         if (!sectionSyncer[i].Complete())
+            return false;
+         }
+     return true; // all tables have been processed
+     }
+  return false;
+}
+
 // --- cEIT ------------------------------------------------------------------
 
 class cEIT : public SI::EIT {
@@ -34,13 +56,13 @@ cEIT::cEIT(cSectionSyncerHash &SectionSyncerHash, int Source, u_char Tid, const
 {
   if (!CheckCRCAndParse())
      return;
-  int HashId = Tid + (getServiceId() << 8);
-  cSectionSyncerEntry *SectionSyncerEntry = SectionSyncerHash.Get(HashId);
-  if (!SectionSyncerEntry) {
-     SectionSyncerEntry = new cSectionSyncerEntry;
-     SectionSyncerHash.Add(SectionSyncerEntry, HashId);
+  int HashId = getServiceId();
+  cEitTables *EitTables = SectionSyncerHash.Get(HashId);
+  if (!EitTables) {
+     EitTables = new cEitTables;
+     SectionSyncerHash.Add(EitTables, HashId);
      }
-  bool Process = SectionSyncerEntry->Sync(getVersionNumber(), getSectionNumber(), getLastSectionNumber());
+  bool Process = EitTables->Check(Tid, getVersionNumber(), getSectionNumber());
   if (Tid != 0x4E && !Process) // we need to set the 'seen' tag to watch the running status of the present/following event
      return;
 
@@ -50,10 +72,8 @@ cEIT::cEIT(cSectionSyncerHash &SectionSyncerHash, int Source, u_char Tid, const
 
   cStateKey ChannelsStateKey;
   cChannels *Channels = cChannels::GetChannelsWrite(ChannelsStateKey, 10);
-  if (!Channels) {
-     SectionSyncerEntry->Repeat(); // let's not miss any section of the EIT
+  if (!Channels)
      return;
-     }
   tChannelID channelID(Source, getOriginalNetworkId(), getTransportStreamId(), getServiceId());
   cChannel *Channel = Channels->GetByChannelID(channelID, true);
   if (!Channel || EpgHandlers.IgnoreChannel(Channel)) {
@@ -64,7 +84,6 @@ cEIT::cEIT(cSectionSyncerHash &SectionSyncerHash, int Source, u_char Tid, const
   cStateKey SchedulesStateKey;
   cSchedules *Schedules = cSchedules::GetSchedulesWrite(SchedulesStateKey, 10);
   if (!Schedules) {
-     SectionSyncerEntry->Repeat(); // let's not miss any section of the EIT
      ChannelsStateKey.Remove(false);
      return;
      }
@@ -361,6 +380,8 @@ cEIT::cEIT(cSectionSyncerHash &SectionSyncerHash, int Source, u_char Tid, const
      EpgHandlers.DropOutdated(pSchedule, SegmentStart, SegmentEnd, Tid, getVersionNumber());
      pSchedule->SetModified();
      }
+  if (Process)
+     EitTables->Processed(Tid, getLastTableId(), getSectionNumber(), getLastSectionNumber(), getSegmentLastSectionNumber());
   SchedulesStateKey.Remove(Modified);
   ChannelsStateKey.Remove(ChannelsModified);
   EpgHandlers.EndSegmentTransfer(Modified);

eit.h

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: eit.h 4.2 2017/05/08 21:10:29 kls Exp $
+ * $Id: eit.h 5.1 2021/03/16 15:10:54 kls Exp $
  */
 
 #ifndef __EIT_H
@@ -13,9 +13,26 @@
 #include "filter.h"
 #include "tools.h"
 
-class cSectionSyncerEntry : public cListObject, public cSectionSyncer {};
+#define NUM_EIT_TABLES  17
 
-class cSectionSyncerHash : public cHash<cSectionSyncerEntry> {
+// Event information (or EPG) is broadcast in tables 0x4E and 0x4F for "present/following" events on
+// "this transponder" (0x4E) and "other transponders" (0x4F), as well as 0x50-0x5F ("all events on this
+// transponder) and 0x60-0x6F ("all events on other transponders). Since it's either "this" or "other",
+// we only use one section syncer for 0x4E/0x4F and 16 syncers for either 0x5X or 0x6X.
+
+class cEitTables : public cListObject {
+private:
+  cSectionSyncerRandom sectionSyncer[NUM_EIT_TABLES]; // for tables 0x4E/0x4F and 0x50-0x5F/0x60-0x6F
+  bool complete;
+  int Index(uchar TableId) { return (TableId < 0x50) ? 0 : (TableId & 0x0F) + 1; }
+public:
+  cEitTables(void) { complete = false; }
+  bool Check(uchar TableId, uchar Version, int SectionNumber);
+  bool Processed(uchar TableId, uchar LastTableId, int SectionNumber, int LastSectionNumber, int SegmentLastSectionNumber = -1);
+  bool Complete(void) { return complete; }
+  };
+
+class cSectionSyncerHash : public cHash<cEitTables> {
 public:
   cSectionSyncerHash(void) : cHash(HASHSIZE, true) {};
   };

filter.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: filter.c 4.3 2017/05/09 08:37:23 kls Exp $
+ * $Id: filter.c 5.1 2021/03/16 15:10:54 kls Exp $
  */
 
 #include "filter.h"
@@ -12,8 +12,9 @@
 
 // --- cSectionSyncer --------------------------------------------------------
 
-cSectionSyncer::cSectionSyncer(void)
+cSectionSyncer::cSectionSyncer(bool Random)
 {
+  random = Random;
   Reset();
 }
 
@@ -23,9 +24,56 @@ void cSectionSyncer::Reset(void)
   currentSection = -1;
   synced = false;
   complete = false;
+  segments = 0;
   memset(sections, 0x00, sizeof(sections));
 }
 
+bool cSectionSyncer::Check(uchar Version, int SectionNumber)
+{
+  if (Version != currentVersion) {
+     Reset();
+     currentVersion = Version;
+     }
+  if (complete)
+     return false;
+  if (!random) {
+     if (!synced) {
+        if (SectionNumber == 0) {
+           currentSection = 0;
+           synced = true;
+           }
+        else
+           return false;
+        }
+     if (SectionNumber != currentSection)
+        return false;
+     }
+  return !GetSectionFlag(SectionNumber);
+}
+
+bool cSectionSyncer::Processed(int SectionNumber, int LastSectionNumber, int SegmentLastSectionNumber)
+{
+  SetSectionFlag(SectionNumber, true); // the flag for this section
+  if (!random)
+     currentSection++;           // expect the next section
+  int Index = SectionNumber / 8; // the segment (byte) in which this section lies
+  uchar b = 0xFF;                // all sections in this segment
+  if (SegmentLastSectionNumber < 0 && Index == LastSectionNumber / 8)
+     SegmentLastSectionNumber = LastSectionNumber;
+  if (SegmentLastSectionNumber >= 0) {
+     b >>= 7 - (SegmentLastSectionNumber & 0x07); // limits them up to the last section in this segment
+     if (!random && SectionNumber == SegmentLastSectionNumber)
+        currentSection = (SectionNumber + 8) & ~0x07; // expect first section of next segment
+     }
+  if (sections[Index] == b)           // all expected sections in this segment have been received
+     segments |= 1 << Index;          // so we set the respective bit in the segments flags
+  uint32_t s = 0xFFFFFFFF;            // all segments
+  s >>= 31 - (LastSectionNumber / 8); // limits them up to the last expected segment
+  complete = segments == s;
+  return complete;
+}
+
+#if DEPRECATED_SECTIONSYNCER_SYNC_REPEAT
 void cSectionSyncer::Repeat(void)
 {
   SetSectionFlag(currentSection, false);
@@ -52,6 +100,7 @@ bool cSectionSyncer::Sync(uchar Version, int Number, int LastNumber)
      complete = true;
   return Result;
 }
+#endif
 
 // --- cFilterData -----------------------------------------------------------
 

filter.h

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: filter.h 4.3 2017/05/09 08:37:23 kls Exp $
+ * $Id: filter.h 5.1 2021/03/16 15:10:54 kls Exp $
  */
 
 #ifndef __FILTER_H
@@ -13,21 +13,52 @@
 #include <sys/types.h>
 #include "tools.h"
 
+#define DEPRECATED_SECTIONSYNCER_SYNC_REPEAT 1
+
 class cSectionSyncer {
 private:
   int currentVersion;
   int currentSection;
+  bool random;
   bool synced;
   bool complete;
+  uint32_t segments;  // bit flags for the 32 segments
   uchar sections[32]; // holds 32 * 8 = 256 bits, as flags for the sections
   void SetSectionFlag(uchar Section, bool On) { if (On) sections[Section / 8] |= (1 << (Section % 8)); else sections[Section / 8] &= ~(1 << (Section % 8)); }
   bool GetSectionFlag(uchar Section) { return sections[Section / 8] & (1 << (Section % 8)); }
 public:
-  cSectionSyncer(void);
+  cSectionSyncer(bool Random = false);
+       ///< Sets up a new section syncer.
+       ///< Call Check() to see whether a given section needs processing. Once the section
+       ///< has been processed, call Processed() to mark it as such. If, for any reason,
+       ///< processing is not completed after calling Check(), nothing special needs to be
+       ///< done. Just don't call Processed() and a later call to Check() with the same
+       ///< SectionNumber will return true again.
+       ///< If Random is true, sections can be processed in random order, not necessarily
+       ///< starting with section 0.
   void Reset(void);
-  void Repeat(void);
+  bool Check(uchar Version, int SectionNumber);
+       ///< Returns true if Version is not the current version, or the given SectionNumber has not
+       ///< been marked as processed, yet. Sections are handled in ascending order, starting at 0,
+       ///< unless Random is true in the constructor call.
+  bool Processed(int SectionNumber, int LastSectionNumber, int SegmentLastSectionNumber = -1);
+       ///< Marks the given SectionNumber as processed.
+       ///< LastSectionNumber is used to determine whether all sections have been processed.
+       ///< SegmentLastSectionNumber can be given to handle partially filled segments (like,
+       ///< for instance in the EIT).
+       ///< Returns true if all sections have been processed.
   bool Complete(void) { return complete; }
+       ///< Returns true if all sections have been processed.
+#if DEPRECATED_SECTIONSYNCER_SYNC_REPEAT
+  void Repeat(void);
   bool Sync(uchar Version, int Number, int LastNumber);
+#endif
+  };
+
+class cSectionSyncerRandom : public cSectionSyncer {
+  ///< Helper class for having an array of random section syncers.
+public:
+  cSectionSyncerRandom(void): cSectionSyncer(true) {}
   };
 
 class cFilterData : public cListObject {

nit.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: nit.c 4.9 2019/05/31 13:25:00 kls Exp $
+ * $Id: nit.c 5.1 2021/03/16 15:10:54 kls Exp $
  */
 
 #include "nit.h"
@@ -43,7 +43,7 @@ void cNitFilter::Process(u_short Pid, u_char Tid, const u_char *Data, int Length
   SI::NIT nit(Data, false);
   if (!nit.CheckCRCAndParse())
      return;
-  if (!sectionSyncer.Sync(nit.getVersionNumber(), nit.getSectionNumber(), nit.getLastSectionNumber()))
+  if (!sectionSyncer.Check(nit.getVersionNumber(), nit.getSectionNumber()))
      return;
   if (DebugNit) {
      char NetworkName[MAXNETWORKNAME] = "";
@@ -63,10 +63,8 @@ void cNitFilter::Process(u_short Pid, u_char Tid, const u_char *Data, int Length
      }
   cStateKey StateKey;
   cChannels *Channels = cChannels::GetChannelsWrite(StateKey, 10);
-  if (!Channels) {
-     sectionSyncer.Repeat(); // let's not miss any section of the NIT
+  if (!Channels)
      return;
-     }
   bool ChannelsModified = false;
   SI::NIT::TransportStream ts;
   for (SI::Loop::Iterator it; nit.transportStreamLoop.getNext(ts, it); ) {
@@ -371,7 +369,7 @@ void cNitFilter::Process(u_short Pid, u_char Tid, const u_char *Data, int Length
           delete d;
           }
       }
-  if (nit.getSectionNumber() == nit.getLastSectionNumber()) {
+  if (sectionSyncer.Processed(nit.getSectionNumber(), nit.getLastSectionNumber())) {
      dbgnit("    trigger sdtFilter for current tp %d\n", Transponder());
      sdtFilter->Trigger(Source());
      }

pat.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: pat.c 4.9 2020/12/18 14:51:57 kls Exp $
+ * $Id: pat.c 5.1 2021/03/16 15:10:54 kls Exp $
  */
 
 #include "pat.h"
@@ -424,7 +424,7 @@ void cPatFilter::Process(u_short Pid, u_char Tid, const u_char *Data, int Length
         SI::PAT pat(Data, false);
         if (!pat.CheckCRCAndParse())
            return;
-        if (sectionSyncer.Sync(pat.getVersionNumber(), pat.getSectionNumber(), pat.getLastSectionNumber())) {
+        if (sectionSyncer.Check(pat.getVersionNumber(), pat.getSectionNumber())) {
            DBGLOG("PAT %d %d -> %d %d/%d", Transponder(), patVersion, pat.getVersionNumber(), pat.getSectionNumber(), pat.getLastSectionNumber());
            if (pat.getVersionNumber() != patVersion) {
               if (pat.getLastSectionNumber() > 0)
@@ -457,7 +457,7 @@ void cPatFilter::Process(u_short Pid, u_char Tid, const u_char *Data, int Length
                      }
                   }
                }
-           if (sectionSyncer.Complete()) { // all PAT sections done
+           if (sectionSyncer.Processed(pat.getSectionNumber(), pat.getLastSectionNumber())) { // all PAT sections done
               if (pmtPidList.Count() != pmtSidList.Count())
                  DBGLOG("  PAT %d: shared PMT PIDs", Transponder());
               if (pmtSidList.Count() && !activePmt)

sdt.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: sdt.c 4.8 2020/06/16 14:50:07 kls Exp $
+ * $Id: sdt.c 5.1 2021/03/16 15:10:54 kls Exp $
  */
 
 #include "sdt.h"
@@ -82,14 +82,12 @@ void cSdtFilter::Process(u_short Pid, u_char Tid, const u_char *Data, int Length
      }
   if (!(source && Transponder()))
      return;
-  if (!sectionSyncer.Sync(sdt.getVersionNumber(), sdt.getSectionNumber(), sdt.getLastSectionNumber()))
+  if (!sectionSyncer.Check(sdt.getVersionNumber(), sdt.getSectionNumber()))
      return;
   cStateKey StateKey;
   cChannels *Channels = cChannels::GetChannelsWrite(StateKey, 10);
-  if (!Channels) {
-     sectionSyncer.Repeat(); // let's not miss any section of the SDT
+  if (!Channels)
      return;
-     }
   dbgsdt("SDT: %2d %2d %2d %s %d\n", sdt.getVersionNumber(), sdt.getSectionNumber(), sdt.getLastSectionNumber(), *cSource::ToString(source), Transponder());
   bool ChannelsModified = false;
   SI::SDT::Service SiSdtService;
@@ -203,7 +201,7 @@ void cSdtFilter::Process(u_short Pid, u_char Tid, const u_char *Data, int Length
             delete LinkChannels;
          }
       }
-  if (sdt.getSectionNumber() == sdt.getLastSectionNumber()) {
+  if (sectionSyncer.Processed(sdt.getSectionNumber(), sdt.getLastSectionNumber())) {
      if (Setup.UpdateChannels == 1 || Setup.UpdateChannels >= 3) {
         ChannelsModified |= Channels->MarkObsoleteChannels(source, sdt.getOriginalNetworkId(), sdt.getTransportStreamId());
         if (source != Source())