[mythtv-users] Another cause of "length mismatch between programinfo" found

[Tom Keddie]

Folks,

I installed myth recently and have been merrily recording but unable to playback using MythFrontEnd.  I kept getting the dreaded "length mismatch between programinfo" message.  There are a few posts about QT bugs but this all seems solved in 0.23.  I've spent a lot of time on this and I finally found the problem, one of my channel names had trailing binary data (nulls I think) that was stuffing up the parsing of QUERY_RECORDINGS Play.  I'm on a Mac but this is irrelevant.

I fixed my database by hand but it seems like the channel scanning code and possibly the parsing of the protocol could be made robust to this.

Here are the details.

*** Error message.

2010-10-02 03:50:47.913 MythSocket(185a160:26): write -> 26 21      QUERY_RECORDINGS Play
2010-10-02 03:50:48.008 MythSocket(185a160:26): read  <- 26 594     40[]:[]Doc Zone[]:[][]:[][]:[]Documentary[]:[]1021[]:[]2_1[]:[]CB...
length mismatch between programinfo
2010-10-02 03:50:48.025 PlaybackBox Error: SortedList is Empty

*** Manual protocol interaction.

24      MYTH_PROTO_VERSION 23056
27      ANN Monitor paraguay.lan 0
16      QUERY_TIME_ZONE
22      QUERY_RECORDINGS Play
5       DONE

paraguay:~ tv$ cat tom.txt | nc -i 2 paraguay.lan 6543 >output.txt

*** Garbage observed in output.txt
.
.
he Mushuau Innu: Surviving Canada[]:[][]:[][]:[]Documentary[]:[]1421[]:[]42_1[]:[]CHNM-DT[]:[]OMNI BC^@^@^@^@^@^@^@^@^@^@^@^@^@[]:[]myth://127.0.0.1:6543/1421_20100911170000.mpg[]:[]1[]:[]-1799739876[]:[]1284249600[]:[]1284253200[]:[]0[]:
.
.

*** Database queries and update.

paraguay:~ tv$ /usr/local/mysql/bin/mysql -umythtv -p mythconverg -e "select name from channel;"
Enter password: 
+----------------------+
| name                 |
+----------------------+
| OMNI BC              |
| CHAN-DT              |
| CIVT-DT              |
| Citytv Vancouver     |
| Vancouver HD         |
+----------------------+
paraguay:~ tv$ /usr/local/mysql/bin/mysql -umythtv -p mythconverg -e "select length(name) from channel;"
Enter password: 
+--------------+
| length(name) |
+--------------+
|           20 |
|            7 |
|            7 |
|           16 |
|           12 |
+--------------+
paraguay:~ tv$ /usr/local/mysql/bin/mysql -umythtv -p mythconverg -e "update channel set name='OMNI BC' where chanid=1421;"
Enter password: 
paraguay:~ tv$ /usr/local/mysql/bin/mysql -umythtv -p mythconverg -e "select length(name) from channel;"
Enter password: 
+--------------+
| length(name) |
+--------------+
|            7 |
|            7 |
|            7 |
|           16 |
|           12 |
+--------------+

*** Manual protocol interaction. #2

paraguay:~ tv$ cat tom.txt | nc -i 2 paraguay.lan 6543 >output1.txt

he Mushuau Innu: Surviving Canada[]:[][]:[][]:[]Documentary[]:[]1421[]:[]42_1[]:[]CHNM-DT[]:[]OMNI BC[]:[]myth://127.0.0.1:6543/1421_20100911170000.mpg[]:[]1[]:[]-1799739876[]:[]1284249600[]:[]1284253200[]:[]0[]:[]0[]:[]0[]:[]paraguay.lan

*** Happy MythFrontEnd

2010-10-02 04:13:03.015 MythSocket(6aed30:26): write -> 26 21      QUERY_RECORDINGS Play
2010-10-02 04:13:03.124 MythSocket(6aed30:26): read  <- 26 23006   40[]:[]Doc Zone[]:[][]:[][]:[]Documentary[]:[]1021[]:[]2_1[]:[]CB...
2010-10-02 04:13:03.194 MythSocket(6aed30:26): write -> 26 530     QUERY_CHECKFILE[]:[]1[]:[]So You Think You Can Dance Canada[]:[][...
2010-10-02 04:13:03.247 MythSocket(6aed30:26): read  <- 26 46      1[]:[]/Volumes/disk3.1/1321_20100930203000.mpg

Cheers,
Tom