[alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file
Hi, I am having a strange issue calling snd_pcm_* alsa-lib functions from a .so file.
The example is a pretty run of the mill .wav file output example in C from the internet, which I have placed in playwav.c. I put the routine that does the pcm play, alsaplaywave(), into a routine and have a duplicate in another external file, test2.c. I named the one in playwav.c alsaplaywav1(), and the one in test2.c alsaplaywav().
The compile is done as follows:
gcc -g3 -Iinclude -fPIC -c test2.c -o test2.o gcc -shared test2.o -o test2.so # # Compiling from .so causes bug, compiling from .o does not # gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav #gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav If the test2.so file is used, the playback has its parameters such as rate messed up, and the result is it plays as fast as possible (series of chirps). If the above line is just changed to test2.o, the playback is fine. Further, if the copy of alsaplaywav() local to the playwav.c file is executed, the playback is correct. It is only when playing from the routine in the .so file that it messes up. To find out what the key point of failure is, I put all of the preamble for the routine up until it does a
snd_pcm_hw_params_set_rate_near() at the calling point (in playwav.c) and commented that out in the routine. The idea was to see exactly which alsa call being done inside the .so caused the malfunction. The rate set appears to be the key. Do that outside the .so, it works, do it inside, it does not. I note that snd_pcm_hw_params_set_rate_near() goes through a few macros in alsa-lib. I think I could debug this better if I can get alsa symbols into gdb. As in the other message, I cannot figure out where the libasound.so gets constructed in the build. I see libasound.a, but no libasound.so. Apologies for not cutting the example down further, but the failure mode is quite complex and that is difficult. Find playwav.c and test2.c attached, and the compile instructions I used above or in cplaywav. The files are fairly small. Thanks for any help.
Scott Franco
Hello,
The issue:
calling across .so (dynamic linking) produces different behavior in ALSA library calls than normal, and causes ALSA to malfunction.
I have minimized my issue to as small a code section as possible. Note the code is from commonly available internet examples, including Free Electrons "Audio in embedded linux systems".
The run is:
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note the only difference between the two runs of "playwave" is if the second module, test2, is linked as a .so or linked as a .o.
The code is: ======================================================================================= playwav.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave1(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } extern void alsaplaywave2(void); int main(int argc, char **argv) { alsaplaywave1(); alsaplaywave2(); return 0; }
================================================================================== test2.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave2(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); }
uname -a Linux samiam-home-pc 4.15.0-51-generic #55-Ubuntu SMP Wed May 15 14:27:21 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
samiam@samiam-home-pc:/usr/lib/x86_64-linux-gnu$ ls -l libasound* lrwxrwxrwx 1 root root 18 Dec 18 20:25 libasound.so -> libasound.so.2.0.0 lrwxrwxrwx 1 root root 18 Dec 18 20:25 libasound.so.2 -> libasound.so.2.0.0 -rw-r--r-- 1 root root 1075496 Dec 18 20:25 libasound.so.2.0.0 samiam@samiam-home-pc:/usr/lib/x86_64-linux-gnu$
--------- Original Message --------- Subject: RE: Serious bug calling ALSA lib functions from .so vs. .o file From: "scott andrew franco" samiam@moorecad.com Date: 6/18/19 8:16 am To: alsa-devel@alsa-project.org
Hello,
The issue:
calling across .so (dynamic linking) produces different behavior in ALSA library calls than normal, and causes ALSA to malfunction.
I have minimized my issue to as small a code section as possible. Note the code is from commonly available internet examples, including Free Electrons "Audio in embedded linux systems".
The run is:
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note the only difference between the two runs of "playwave" is if the second module, test2, is linked as a .so or linked as a .o.
The code is: ======================================================================================= playwav.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave1(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } extern void alsaplaywave2(void); int main(int argc, char **argv) { alsaplaywave1(); alsaplaywave2(); return 0; }
================================================================================== test2.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave2(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); }
Dne 18. 06. 19 v 17:16 scott andrew franco napsal(a):
Hello,
The issue:
calling across .so (dynamic linking) produces different behavior in ALSA library calls than normal, and causes ALSA to malfunction.
I have minimized my issue to as small a code section as possible. Note the code is from commonly available internet examples, including Free Electrons "Audio in embedded linux systems".
It seems like a linker issue. I think that you must link .so to -lasound, too. (add -lasound to the command producing your .so library to satisfy the versioned symbols)
Jaroslav
The run is:
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note the only difference between the two runs of "playwave" is if the second module, test2, is linked as a .so or linked as a .o.
The code is:
playwav.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave1(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } extern void alsaplaywave2(void); int main(int argc, char **argv) { alsaplaywave1(); alsaplaywave2(); return 0; }
================================================================================== test2.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave2(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
Hi, and thanks for the reply.
I think that you must link .so to -lasound, too.
This was done and shows in the command line example below, IE,
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note that in both the "succeeds" case and the "fails" case carry the -lasound option. It would not compile if not.
Scott Franco
--------- Original Message --------- Subject: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "Jaroslav Kysela" perex@perex.cz Date: 6/18/19 11:18 am To: "scott andrew franco" samiam@moorecad.com Cc: alsa-devel@alsa-project.org
Dne 18. 06. 19 v 17:16 scott andrew franco napsal(a):
Hello,
The issue:
calling across .so (dynamic linking) produces different behavior in ALSA library calls than normal, and causes ALSA to malfunction.
I have minimized my issue to as small a code section as possible. Note the code is from commonly available internet examples, including Free Electrons "Audio in embedded linux systems".
It seems like a linker issue. I think that you must link .so to -lasound, too. (add -lasound to the command producing your .so library to satisfy the versioned symbols)
Jaroslav
The run is:
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note the only difference between the two runs of "playwave" is if the second module, test2, is linked as a .so or linked as a .o.
The code is:
playwav.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave1(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } extern void alsaplaywave2(void); int main(int argc, char **argv) { alsaplaywave1(); alsaplaywave2(); return 0; }
================================================================================== test2.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave2(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
-- Jaroslav Kysela perex@perex.cz Linux Sound Maintainer; ALSA Project; Red Hat, Inc. _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
PS. I really appreciate the help, I have spent more than a week on this, it is a serious blocking issue.
I've gone over the example I posted quite carefully. I recommend you try the example out. You just need the two source files below (test2.c and playwav.c). and execute the commands shown below.
The fact that it fails only in the .so file can explain why this bug hasn't affected more user code, since most people don't call alsa from another library. However, it does not explain everything since I believe there must be a few users who do put the calling code in a library.
Thanks,
Scott Franco
--------- Original Message --------- Subject: RE: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "scott andrew franco" samiam@moorecad.com Date: 6/18/19 11:33 am To: "Jaroslav Kysela" perex@perex.cz Cc: alsa-devel@alsa-project.org
Hi, and thanks for the reply.
I think that you must link .so to -lasound, too.
This was done and shows in the command line example below, IE,
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note that in both the "succeeds" case and the "fails" case carry the -lasound option. It would not compile if not.
Scott Franco
--------- Original Message --------- Subject: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "Jaroslav Kysela" perex@perex.cz Date: 6/18/19 11:18 am To: "scott andrew franco" samiam@moorecad.com Cc: alsa-devel@alsa-project.org
Dne 18. 06. 19 v 17:16 scott andrew franco napsal(a):
Hello,
The issue:
calling across .so (dynamic linking) produces different behavior in ALSA library calls than normal, and causes ALSA to malfunction.
I have minimized my issue to as small a code section as possible. Note the code is from commonly available internet examples, including Free Electrons "Audio in embedded linux systems".
It seems like a linker issue. I think that you must link .so to -lasound, too. (add -lasound to the command producing your .so library to satisfy the versioned symbols)
Jaroslav
The run is:
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note the only difference between the two runs of "playwave" is if the second module, test2, is linked as a .so or linked as a .o.
The code is:
playwav.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave1(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } extern void alsaplaywave2(void); int main(int argc, char **argv) { alsaplaywave1(); alsaplaywave2(); return 0; }
================================================================================== test2.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave2(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
-- Jaroslav Kysela perex@perex.cz Linux Sound Maintainer; ALSA Project; Red Hat, Inc. _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
On Tue, 18 Jun 2019 20:59:19 +0200, scott andrew franco wrote:
PS. I really appreciate the help, I have spent more than a week on this, it is a serious blocking issue.
I've gone over the example I posted quite carefully. I recommend you try the example out. You just need the two source files below (test2.c and playwav.c). and execute the commands shown below.
The fact that it fails only in the .so file can explain why this bug hasn't affected more user code, since most people don't call alsa from another library. However, it does not explain everything since I believe there must be a few users who do put the calling code in a library.
What Jaroslav pointed is to pass -lasound2 at creating the *.so file, not at linking to the final binary. That is,
% gcc -shared test2.o -o test2.so -lasound
Otherwise the linker won't get the proper versioned symbol, hence an incorrect symbol may be taken instead of the expected versioned one.
Calling ALSA library from a shared object is commonly done, e.g. PulseAudio. The tricky part is the versioned symbol handling, and it's not specific to ALSA-lib but a generic problem.
Takashi
Thanks,
Scott Franco
--------- Original Message --------- Subject: RE: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "scott andrew franco" samiam@moorecad.com Date: 6/18/19 11:33 am To: "Jaroslav Kysela" perex@perex.cz Cc: alsa-devel@alsa-project.org
Hi, and thanks for the reply.
I think that you must link .so to -lasound, too.
This was done and shows in the command line example below, IE,
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note that in both the "succeeds" case and the "fails" case carry the -lasound option. It would not compile if not.
Scott Franco
--------- Original Message --------- Subject: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "Jaroslav Kysela" perex@perex.cz Date: 6/18/19 11:18 am To: "scott andrew franco" samiam@moorecad.com Cc: alsa-devel@alsa-project.org
Dne 18. 06. 19 v 17:16 scott andrew franco napsal(a):
Hello,
The issue:
calling across .so (dynamic linking) produces different behavior in ALSA library calls than normal, and causes ALSA to malfunction.
I have minimized my issue to as small a code section as possible. Note the code is from commonly available internet examples, including Free Electrons "Audio in embedded linux systems".
It seems like a linker issue. I think that you must link .so to -lasound, too. (add -lasound to the command producing your .so library to satisfy the versioned symbols)
Jaroslav
The run is:
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note the only difference between the two runs of "playwave" is if the second module, test2, is linked as a .so or linked as a .o.
The code is:
playwav.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave1(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } extern void alsaplaywave2(void); int main(int argc, char **argv) { alsaplaywave1(); alsaplaywave2(); return 0; }
================================================================================== test2.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave2(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
-- Jaroslav Kysela perex@perex.cz Linux Sound Maintainer; ALSA Project; Red Hat, Inc. _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
Ok I see, apologies. Will try that.
Scott
--------- Original Message --------- Subject: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "Takashi Iwai" tiwai@suse.de Date: 6/18/19 1:49 pm To: "scott andrew franco" samiam@moorecad.com Cc: alsa-devel@alsa-project.org
On Tue, 18 Jun 2019 20:59:19 +0200, scott andrew franco wrote:
PS. I really appreciate the help, I have spent more than a week on this, it is a serious blocking issue.
I've gone over the example I posted quite carefully. I recommend you try the example out. You just need the two source files below (test2.c and playwav.c). and execute the commands shown below.
The fact that it fails only in the .so file can explain why this bug hasn't affected more user code, since most people don't call alsa from another library. However, it does not explain everything since I believe there must be a few users who do put the calling code in a library.
What Jaroslav pointed is to pass -lasound2 at creating the *.so file, not at linking to the final binary. That is,
% gcc -shared test2.o -o test2.so -lasound
Otherwise the linker won't get the proper versioned symbol, hence an incorrect symbol may be taken instead of the expected versioned one.
Calling ALSA library from a shared object is commonly done, e.g. PulseAudio. The tricky part is the versioned symbol handling, and it's not specific to ALSA-lib but a generic problem.
Takashi
Thanks,
Scott Franco
--------- Original Message --------- Subject: RE: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "scott andrew franco" samiam@moorecad.com Date: 6/18/19 11:33 am To: "Jaroslav Kysela" perex@perex.cz Cc: alsa-devel@alsa-project.org
Hi, and thanks for the reply.
I think that you must link .so to -lasound, too.
This was done and shows in the command line example below, IE,
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note that in both the "succeeds" case and the "fails" case carry the -lasound option. It would not compile if not.
Scott Franco
--------- Original Message --------- Subject: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "Jaroslav Kysela" perex@perex.cz Date: 6/18/19 11:18 am To: "scott andrew franco" samiam@moorecad.com Cc: alsa-devel@alsa-project.org
Dne 18. 06. 19 v 17:16 scott andrew franco napsal(a):
Hello,
The issue:
calling across .so (dynamic linking) produces different behavior in ALSA library calls than normal, and causes ALSA to malfunction.
I have minimized my issue to as small a code section as possible. Note the code is from commonly available internet examples, including Free Electrons "Audio in embedded linux systems".
It seems like a linker issue. I think that you must link .so to -lasound, too. (add -lasound to the command producing your .so library to satisfy the versioned symbols)
Jaroslav
The run is:
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note the only difference between the two runs of "playwave" is if the second module, test2, is linked as a .so or linked as a .o.
The code is:
playwav.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave1(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } extern void alsaplaywave2(void); int main(int argc, char **argv) { alsaplaywave1(); alsaplaywave2(); return 0; }
================================================================================== test2.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave2(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
-- Jaroslav Kysela perex@perex.cz Linux Sound Maintainer; ALSA Project; Red Hat, Inc. _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
_______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
Fixed.
Again, apologies for my being dense there.
This is *great* it all works now. I don't think I would have figured out that link issue on my own.
Scott Franco
--------- Original Message --------- Subject: RE: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "scott andrew franco" samiam@moorecad.com Date: 6/18/19 2:10 pm To: "Takashi Iwai" tiwai@suse.de Cc: alsa-devel@alsa-project.org
Ok I see, apologies. Will try that.
Scott
--------- Original Message --------- Subject: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "Takashi Iwai" tiwai@suse.de Date: 6/18/19 1:49 pm To: "scott andrew franco" samiam@moorecad.com Cc: alsa-devel@alsa-project.org
On Tue, 18 Jun 2019 20:59:19 +0200, scott andrew franco wrote:
PS. I really appreciate the help, I have spent more than a week on this, it is a serious blocking issue.
I've gone over the example I posted quite carefully. I recommend you try the example out. You just need the two source files below (test2.c and playwav.c). and execute the commands shown below.
The fact that it fails only in the .so file can explain why this bug hasn't affected more user code, since most people don't call alsa from another library. However, it does not explain everything since I believe there must be a few users who do put the calling code in a library.
What Jaroslav pointed is to pass -lasound2 at creating the *.so file, not at linking to the final binary. That is,
% gcc -shared test2.o -o test2.so -lasound
Otherwise the linker won't get the proper versioned symbol, hence an incorrect symbol may be taken instead of the expected versioned one.
Calling ALSA library from a shared object is commonly done, e.g. PulseAudio. The tricky part is the versioned symbol handling, and it's not specific to ALSA-lib but a generic problem.
Takashi
Thanks,
Scott Franco
--------- Original Message --------- Subject: RE: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "scott andrew franco" samiam@moorecad.com Date: 6/18/19 11:33 am To: "Jaroslav Kysela" perex@perex.cz Cc: alsa-devel@alsa-project.org
Hi, and thanks for the reply.
I think that you must link .so to -lasound, too.
This was done and shows in the command line example below, IE,
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note that in both the "succeeds" case and the "fails" case carry the -lasound option. It would not compile if not.
Scott Franco
--------- Original Message --------- Subject: Re: [alsa-devel] Serious bug calling ALSA lib functions from .so vs. .o file From: "Jaroslav Kysela" perex@perex.cz Date: 6/18/19 11:18 am To: "scott andrew franco" samiam@moorecad.com Cc: alsa-devel@alsa-project.org
Dne 18. 06. 19 v 17:16 scott andrew franco napsal(a):
Hello,
The issue:
calling across .so (dynamic linking) produces different behavior in ALSA library calls than normal, and causes ALSA to malfunction.
I have minimized my issue to as small a code section as possible. Note the code is from commonly available internet examples, including Free Electrons "Audio in embedded linux systems".
It seems like a linker issue. I think that you must link .so to -lasound, too. (add -lasound to the command producing your .so library to satisfy the versioned symbols)
Jaroslav
The run is:
samiam@samiam-home-pc:~/projects/petit_ami$ gcc -fPIC -c test2.c -o test2.o samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.so -lasound -o playwav samiam@samiam-home-pc:~/projeclufthansa check reservationts/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 0 samiam@samiam-home-pc:~/projects/petit_ami$ gcc -g3 -Iinclude linux/playwav.c ./test2.o -lasound -o playwav samiam@samiam-home-pc:~/projects/petit_ami$ ./playwav alsaplaywave: rate: 1 alsaplaywave: rate: 1
Note the only difference between the two runs of "playwave" is if the second module, test2, is linked as a .so or linked as a .o.
The code is:
playwav.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave1(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } extern void alsaplaywave2(void); int main(int argc, char **argv) { alsaplaywave1(); alsaplaywave2(); return 0; }
================================================================================== test2.c #include <alsa/asoundlib.h> #include <stdio.h> void alsaplaywave2(void) { snd_pcm_t *pcm_handle; snd_pcm_hw_params_t *params; unsigned int val; unsigned int rate; int r; /* open pcm device */ r = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, 0); if (r < 0) printf("Cannot open PCM output device"); snd_pcm_hw_params_alloca(¶ms); /* get hw parameter block */ snd_pcm_hw_params_any(pcm_handle, params); r = snd_pcm_hw_params_set_access(pcm_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); if (r < 0) printf("Cannot set interleaved mode"); r = snd_pcm_hw_params_set_format(pcm_handle, params, SND_PCM_FORMAT_S16_LE); if (r < 0) printf("Cannot set format"); r = snd_pcm_hw_params_set_channels(pcm_handle, params, 2); if (r < 0) printf("Cannot set channels number"); val = 44100; r = snd_pcm_hw_params_set_rate_near(pcm_handle, params, &rate, 0); if (r < 0) printf("Cannot set rate"); snd_pcm_hw_params_get_rate(params, &rate, 0); printf("alsaplaywave: rate: %d\n", rate); snd_pcm_close(pcm_handle); } _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
-- Jaroslav Kysela perex@perex.cz Linux Sound Maintainer; ALSA Project; Red Hat, Inc. _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
_______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
participants (3)
-
Jaroslav Kysela -
scott andrew franco -
Takashi Iwai