[LAU] [Jack-Devel] jack2 turned verbose
brendan.jones.it at gmail.com
Mon Jun 4 20:06:09 UTC 2012
On 06/01/2012 03:58 PM, Robin Gareus wrote:
> Hi David,
> On 06/01/2012 03:48 PM, David Adler wrote:
>> On Fri, Jun 1, 2012 at 2:52 PM, Robin Gareus wrote:
>>> It might have to do with Arch's compiler[-flags] and how jack2 uses
>>> unions .. or scoping: JackGlobals vs Engine-Parameters.. although I
>>> don't have an explanation.. all seems good.
>> Compiler flags (for 32bit) are, (from unaltered /etc/makepkg.conf):
>> CXXFLAGS="-march=i686 -mtune=generic -O2 -pipe -fstack-protector
>> --param=ssp-buffer-size=4 -D_FORTIFY_SOURCE=2"
>>> A hunch: it could be caused by using 'server_ptr->verbose.b' (a union)
>>> as boolean. The sever only checks "if (server_ptr->verbose.b)". The
>>> union itself comprises other uninitialized values that could make it
>>> evaluate to true (though it shouldn't, but maybe some compiler
>>> optimization casts it to (int) instead of (bool) )
>>> I know this is the '-users' list (I'm ccing jack-devel), but could
>>> someone who experiences the problem try to track it down?
>>> Basically just add a few printf()'s. Start at: common/JackControlAPI.cpp
>>> - line 926 - before the call to "new JackServer(..)" add
>>> printf("DEBUG verbose: %s\n",(server_ptr->verbose.b)?"on":"off");
>>> recompile, launch jackd. If it prints "verbose: on", sth is wrong with
>>> parameter initialization in main() or with using unions. If it's "off"
>>> the problem sits deeper:
>> DEBUG verbose: on
>>> add a line just after common/JackServer.cpp line 66
>>> printf("DEBUG verbose2: %s\n",(JackGlobals::fVerbose)?"on":"off");
>> above, your line number didn't match exactly, so we seem to have
>> different versions (1.9.7 here). Thus, I wasn't exactly sure where to
>> add the prinf() and did the following:
>> JackServerGlobals::fUserCount = 1; // One user
>> printf("DEBUG verbose2: %s\n",(JackGlobals::fVerbose)?"on":"off");
>> JackGlobals::fVerbose = verbose;
>> printf("DEBUG verbose3: %s\n",(JackGlobals::fVerbose)?"on":"off");
>> which prints:
>> DEBUG verbose2: off
>> DEBUG verbose3: on
>>> A crude test for the union() hunch would be to change
>>> common/JackControlAPI.h line 53:
>>> "union jackctl_parameter_value"
>>> "struct jackctl_parameter_value"
>>> and compile with '-fpermissive' like this:
>>> CXXFLAGS="-fpermissive" ./waf configure
>> Again, mismatching line numbers. I assume you meant the line:
>> union jackctl_parameter_value verbose;
>> Changing that to struct fixes both issues I reported,
>> the verbose output and exit on last client close.
>> So we seem to be getting somewhere. Nice.
>> thanks Robin,
> just a quick re: the line-numbers refered to git-head
> currently 007cdc37142a
> It looks like it is indeed caused by using unions to check for /true/.
> "if ([bool/int/..]union) -> always true"
> But I'm at a loss what'd cause those issues and how to best fix it.
> Maybe someone else can take it from here. It should be sufficient info
> to file a bug report at https://github.com/jackaudio/jack2/issues
> Linux-audio-user mailing list
> Linux-audio-user at lists.linuxaudio.org
I've had a closer look at this and this patch seems to be working for me
(their's no equivalent bool in jack_driver_param_value_t)
diff -Nurp '-x*~' jack-1.9.8.orig/common/JackControlAPI.cpp
--- jack-1.9.8.orig/common/JackControlAPI.cpp 2011-12-19
+++ jack-1.9.8/common/JackControlAPI.cpp 2012-06-04 21:57:59.264581780 +0200
@@ -246,7 +246,7 @@ jackctl_add_driver_parameters(
jackctl_type = JackParamBool;
- jackctl_value.b = descriptor_ptr->value.i;
+ jackctl_value.b = (descriptor_ptr->value.i > 0);
jack_error("unknown driver parameter type %i",
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