On Sun, 25 Nov 2007, Lennart Poettering wrote:
Hi!
Apparently alsa-libs .15 is leaking memory when using snd_pcm_open() on some devices that cannot be opened.
On my USB wecam which has only a single mono audio stream, opening it as "front:3" (which of course fails) leaks a bit of memory. Consider this example:
<snip> #include <asoundlib.h> #include <assert.h>
int main(int argc, char *argv[]) { snd_pcm_t *pcm;
if (snd_pcm_open(&pcm, "front:3", SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK) == 0) { int r = snd_pcm_close(pcm); assert(r == 0); } snd_config_update_free_global(); return 0;}
</snip>
And there they are gone, the 10 bytes of memory. Here's a snippet from valgrinding this program:
==22198== 10 bytes in 1 blocks are definitely lost in loss record 1 of 3 ==22198== at 0x4023765: malloc (vg_replace_malloc.c:149) ==22198== by 0x417C44F: strdup (strdup.c:43) ==22198== by 0x4071954: snd_determine_driver (in /usr/lib/libasound.so.2.0.0) ==22198== by 0x406E80C: snd_config_hook_load_for_all_cards (in /usr/lib/libasound.so.2.0.0) ==22198== by 0x406EC7C: (within /usr/lib/libasound.so.2.0.0) ==22198== by 0x406F896: snd_config_searcha_hooks (in /usr/lib/libasound.so.2.0.0) ==22198== by 0x406FA74: snd_config_search_alias_hooks (in /usr/lib/libasound.so.2.0.0) ==22198== by 0x406FCD9: snd_config_search_definition (in /usr/lib/libasound.so.2.0.0) ==22198== by 0x40952FE: (within /usr/lib/libasound.so.2.0.0) ==22198== by 0x80484D7: main (in /home/lennart/alsa-test)
Broken valgrind? I cannot reproduce here and from first glance, the error path in snd_config_hook_load_for_all_cards is good.
Jaroslav
----- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project