After days of testing, I got a crash (of sorts) out of my program. More of a hang than a crash. So I attached gdb to the process and looked around. My main thread appears to be hung deep inside a jack call, via jack_port_disconnect(). This is a point in my code where it cleans up after an jack-attached media player that is done playing. The player process terminates when it's jack connections are disconnected. I re-started the code execution and then stopped it again to find that the main thread was still waiting at the same libc_read() spot. After taking a look at the jack source code, I didn't find that jack_port_disconnect() would result in a read any place down the jack call chain. To be fair to jack, I am still mostly unfamiliar with the library structure, so I could be missing something. Any insight as to what I might be doing wrong? The port I am passing to jack_port_disconnect() appears to be valid, unless my code is overwriting memory. Backtrace of the main thread is below.
Thanks all.
Ethan...
(gdb) bt full
#0 __libc_read (nbytes=4, buf=0x7fffad4ed248, fd=5) at ../sysdeps/unix/sysv/linux/read.c:26
resultvar = 18446744073709551104
sc_cancel_oldtype = 0
__arg3 = <optimized out>
_a2 = <optimized out>
sc_ret = <optimized out>
__value = <optimized out>
__arg1 = <optimized out>
_a3 = <optimized out>
resultvar = <optimized out>
resultvar = <optimized out>
__arg2 = <optimized out>
_a1 = <optimized out>
#1 __libc_read (fd=5, buf=0x7fffad4ed248, nbytes=4) at ../sysdeps/unix/sysv/linux/read.c:24
No locals.
#2 0x00007fab6fe13ead in ?? () from /lib/x86_64-linux-gnu/libjack.so.0
No symbol table info available.
#3 0x00007fab6fe02e2a in ?? () from /lib/x86_64-linux-gnu/libjack.so.0
No symbol table info available.
#4 0x00007fab6fe03768 in ?? () from /lib/x86_64-linux-gnu/libjack.so.0
No symbol table info available.
#5 0x00007fab6fdf8598 in ?? () from /lib/x86_64-linux-gnu/libjack.so.0
No symbol table info available.
#6 0x0000564ac911610a in releaseQueueRecord (root=0x564ac9134260 <queueList>, rec=0x7fab3004c910, force=0 '\000') at data.c:473
[NOTE: this line is: jack_port_disconnect(mixEngine->client, *port); ]
c = 1
cmax = 2
port = 0x564acaf81278
prev = 0x564ac9134260 <queueList>
current = 0x7fab3004c910
instance = 0x564acaf80be0
logID = 9126049
tmp = <optimized out>
#7 0x0000564ac91057c5 in NextListItem (lastStat=2, curQueRec=0x564ac9134260 <queueList>, firstp=0x7fffad4ed418, sbtime=0x7fffad4ed41c, remtime=0, isPlaying=0x7fffad4ed416 "") at automate.c:811
.... Blah, blah, blah....