-----Original Message----- From: Jaroslav Kysela <[EMAIL PROTECTED]> Date: Sat, 1 Dec 2001 19:33:55 +0100 (CET) To: Kyle Centers <[EMAIL PROTECTED]> Subject: Re: [Alsa-devel] bug in alsa-lib
> On Sun, 2 Dec 2001, Kyle Centers wrote: > > > Hi! > > > > I've been working with an xmms plugin the last few days, and I seem to > > have found a bug in libasound.so. > > > > Calling snd_pcm_open(...) in a program compiled as an executable > > binary works fine (ie it returns no errors, and doesn't die). But if > > compiled as part of a dynamic library, say an xmms output plugin, it > > dies, with the following error messages: > > > > ALSA lib dlmisc.c:99:(snd_dlsym_verify) unable to verify version for > > symbol and_config_hook_load > > > > ALSA lib conf.c:2287:(snd_config_hooks_call) symbol > > snd_config_hook_load is not defined inside (null) > > > > I am still working on the second one, but I found a solution to the > > first one. > > > > The problem, is in dlmisc.c at line 2278: > > h = snd_dlopen(lib, RTLD_NOW); > > > > I'm not really sure why, but *lib is null at this point. The result is > > that when dlopen is called, inside snd_dlopen, the filename is null, > > which dlopen takes to mean the main program (according to the man > > page). With a standard binary executable, that's fine, > > because-actually, I'm not sure why that's ok. But I would venture to > > guess it has to do with libasound getting loaded with the binary. But > > when compiling a dynamic library, the main program is something else - > > in this case xmms, which knows nothing about libasound (all the alsa > > stuff in inside the plugin). > > > > I did managed to fix the problem, but my solution is a hack. in the > > call to snd_dlopen, I replaced lib with "/usr/lib/libasound.so", > > explicitly telling it to load the asound library. Now, the error is > > gone (the first one. I havent' gotten to the second, although I > > suspect it is similar). Anyone know how to fix ths properly? > > Yes, the xmms engine should add the RTLD_GLOBAL flag to dlopen() call for > external plugins: > > /* If the following bit is set in the MODE argument to `dlopen', > the symbols of the loaded object and its dependencies are made > visible as if the object were linked directly into the program. */ > #define RTLD_GLOBAL 0x00100 > You're right. I added flag to xmms, and the plugin works perfecty now. With your permission (since you made the suggestion), I'll send an email off to the xmms team about it. > I'm sorry for this, but it really doesn't make any sense to create Sorry? no need to say sorry, you're completely right. > another instance of dynamic library when symbol can be already > resolved using existing instances. > > Jaroslav > > ----- > Jaroslav Kysela <[EMAIL PROTECTED]> > SuSE Linux http://www.suse.com > ALSA Project http://www.alsa-project.org > > -- _______________________________________________ Sign-up for your own FREE Personalized E-mail at Mail.com http://www.mail.com/?sr=signup 1 cent a minute calls anywhere in the U.S.! http://www.getpennytalk.com/cgi-bin/adforward.cgi?p_key=RG9853KJ&url=http://www.getpennytalk.com _______________________________________________ Alsa-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-devel
