[mythtv-commits] Ticket #13623: mythfilldatabase may not process valid XMLTV files if program starttime order is not increasing

[MythTV]

#13623: mythfilldatabase may not process valid XMLTV files if program starttime
order is not increasing
-------------------------------------------+--------------------------
     Reporter:  Gary Buhrmaster            |      Owner:  (none)
         Type:  Bug Report - General       |     Status:  new
     Priority:  minor                      |  Milestone:  needs_triage
    Component:  MythTV - Mythfilldatabase  |    Version:  Master Head
     Severity:  medium                     |   Keywords:
Ticket locked:  0                          |
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 mythfilldatabase (with a9aa006139) may no longer process valid XMLTV files
 if the program starttime order is not increasing.

 Originally reported to the XMLTV project, where it was pointed out that
 the issue is actually due to a MythTV issue.  As the original reporter
 chose not to create a MythTV ticket (s/he found their own workaround),
 here is what seems to be the essential part of the original issue so that
 it can be addressed here:

 In a9aa006139 a new (to mythfilldatabase) test was added to check that the
 starttime was increasing with each new program element on the same
 channel, and reject the input file if it was not.

 While many (most?) XMLTV grabbers appear to return the data in starttime
 order (and for that matter, channel and starttime order), any such order
 requirement is not part of the specification, and the original reporter
 ran into this issue with their chosen grabber for a particular day.

 The order check should be removed to support compliant source files.

 FWIW, as I recall (it has been a long time since I last looked at the code
 in question), MythTV itself does its own internal sorting of the program
 data that it processes for its own purposes.

 The mitigation until this issue is resolved is to run the output of a
 grabber through TV_SORT (but note that if there is a lot of source data
 TV_SORT can be very resource intensive (lots of memory and cpu)).

 **COMPLETELY** untested patch (not compiled, let alone tested, just sort
 of looks right):

 {{{
 diff --git a/mythtv/programs/mythfilldatabase/xmltvparser.cpp
 b/mythtv/programs/mythfilldatabase/xmltvparser.cpp
 index 78f22170cd..bbce136c9d 100644
 --- a/mythtv/programs/mythfilldatabase/xmltvparser.cpp
 +++ b/mythtv/programs/mythfilldatabase/xmltvparser.cpp
 @@ -205,8 +205,6 @@ bool XMLTVParser::parseFile(
      QString aggregatedTitle;
      QString aggregatedDesc;
      bool haveReadTV = false;
 -    QString last_channel = ""; //xmltvId of the last program element we
 read
 -    QDateTime last_starttime; //starttime of the last program element we
 read
      while (!xml.atEnd() && !xml.hasError() && (! (xml.isEndElement() &&
 xml.name() == "tv")))
      {
          if (xml.readNextStartElement())
 @@ -709,23 +707,6 @@ bool XMLTVParser::parseFile(
                  else
                  {
                      // so we have a (relatively) clean program element
 now, which is good enough to process or to store
 -                    if (pginfo->m_channel != last_channel) {
 -                        //we have a channel change here
 -                        last_channel = pginfo->m_channel;
 -                        last_starttime = QDateTime(QDate(1970, 1, 1),
 QTime(0, 0, 0)); //initialize it to a time far, far away ...
 -                    }
 -                    else {
 -                        //we are still on the same channel
 -                        if (pginfo->m_starttime >= last_starttime) {
 -                            last_starttime = pginfo->m_starttime;
 -                        }
 -                        else {
 -                            LOG(VB_GENERAL, LOG_ERR, QString("Malformed
 XML file, program out of order at line %1,
 %2").arg(xml.lineNumber()).arg(xml.errorString()));
 -                            delete pginfo;
 -                            return false;
 -                        }
 -                    }
 -
                      if (pginfo->m_clumpidx.isEmpty())
 (*proglist)[pginfo->m_channel].push_back(*pginfo);
                      else
 }}}

-- 
Ticket URL: <https://code.mythtv.org/trac/ticket/13623>
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