Mitul Sen (misen) wrote:
I am making some changes to the alsa-lib code and I have built alsa-lib. But I don't think its really picking up my changes. How can I make sure that my application uses the
modified library? I don't have to load any modules, do I? I am sorry if this is too basic a question but I couldn't find the info on a quick google search. Basically what I want to know is what are the steps to develop alsa-lib. This is what I did
- Downloaded the source code
- Configured the system using ./configure
- Did a build using make
- Did a "make install"
Am I missing something here?
It looks correct. Do an ls -l /usr/lib/libasound*. The file there should have the same timestamp as the file in your build directory. If it doesn't, it didn't install. You could just copy it over.
Make sure there is no other copy in /lib.
Also regarding the original problem, when I run my program, the output of /proc/asound/card0/pcm0p/sub0/hw_params is
access: MMAP_INTERLEAVED format: S16_LE subformat: STD channels: 2 rate: 48000 (48000/1) period_size: 32 buffer_size: 1024
This is clearly not what it should be since the data access should be RW_NONINTERLEAVED, format should be MU_LAW, there is only one channel and rate is 8000. Which would mean that alsa assumes a different set of parameters (for mu law)from what the data actually is. Am I right in thinking this?
Just got back after a long break and trying to pick up the threads again:-)
Again, any help will be much appreciated.
Unless your changes changed the mu-law code to use your card's mu-law decoder, they will still be the decoded values.
The best way to do this is to compile your program with debugging enabled ( -ggdb -O0) and the alsa library with debugging enabled. ./configure --help should give you the option. Then move only the library to /usr/lib and run your program as gdb --args yourprogram yourargs . You can see the info on how to run gdb in info gdb . With the debugger you can step through the program and the library to see where it is not working the way you expected. But you don't want to leave it like that as it is very inefficient.
If your code works for the mu-law, you could submit a patch. Of course, you would have to check for the functionality and branch to the old code if the card doesn't support mu-law decoding.