Re: [alsa-devel] Strange div-by-zero in alsa-lib 1.0.20's snd_pcm_mmap_begin()

At Sun, 16 Aug 2009 18:24:35 -0400, Daniel Chen wrote:

Hi,

In https://bugs.launchpad.net/ubuntu/+source/alsa-lib/+bug/412677 we're debugging an issue where snd_pcm_mmap_begin(), at line 6409 with

*offset = *pcm->appl.ptr % pcm->buffer_size;

appears to have pcm->buffer_size == 0. What's the correct approach in handling this corner case?

We could add a sanity check in the function, of course. But relying on it doesn't sound nice.

At least, the caller should be surely at the certain state that the buffer has been set up, i.e. checking whether snd_pcm_state() returns SETUP or better condition.

Takashi