Since alsa bug tracker does not work for me for weeks, I have to report bug here. Sorry if it a wrong place.
So, to reproduce memory leak (Alsa lib used v.1.0.27), you have to use next asound.conf:
pcm_slave.myslave { pcm "hw:0,0" }
pcm.mysnoop { type dsnoop ipc_key 1024 slave myslave }
Then you simply do:
snd_pcm_open(&pcm_handle, "mysnoop", SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK); snd_pcm_close(pcm_handle); snd_config_update_free_global();
Valgrind will show something like this:
==7889== ==7889== HEAP SUMMARY: ==7889== in use at exit: 15,854 bytes in 871 blocks ==7889== total heap usage: 333,212 allocs, 332,341 frees, 11,695,490 bytes allocated ==7889== ==7889== 15,834 (6,264 direct, 9,570 indirect) bytes in 174 blocks are definitely lost in loss record 6 of 6 ==7889== at 0x4027CBF: calloc (vg_replace_malloc.c:566) ==7889== by 0x406B416: _snd_config_make (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x406C69C: snd_config_make (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x406C861: snd_config_make_compound (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x406D00C: _snd_config_copy (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x406F112: snd_config_walk (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x406FE04: snd_config_copy (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x4070370: snd_config_expand (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x407107E: snd_config_search_definition (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x40D2C22: _snd_pcm_direct_get_slave_ipc_offset (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x40D68A2: snd1_pcm_direct_parse_open_conf (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x40D28CA: _snd_pcm_dsnoop_open (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x40909C4: snd_pcm_open_conf (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x4091036: snd_pcm_open_noupdate (in /usr/lib/libasound.so.2.0.0) ==7889== by 0x804873D: main (in /home/blah/al/a.out) ==7889== ==7889== LEAK SUMMARY: ==7889== definitely lost: 6,264 bytes in 174 blocks ==7889== indirectly lost: 9,570 bytes in 696 blocks ==7889== possibly lost: 0 bytes in 0 blocks ==7889== still reachable: 20 bytes in 1 blocks ==7889== suppressed: 0 bytes in 0 blocks ==7889== Reachable blocks (those to which a pointer was found) are not shown. ==7889== To see them, rerun with: --leak-check=full --show-reachable=yes ==7889== ==7889== For counts of detected and suppressed errors, rerun with: -v ==7889== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)