Massive sound changes / fix (24/32bit pcm support, new sampling rate converter, various fixes)

[Alexander Leidinger]

Ariff Abdullah <skywizard at MyBSD.org.my> wrote:

> More good news is, I've already added sysctl controller to tune vchan
> rate on the fly, something like sysctl hw.snd.pcm0.vchanrate=xxx. Stay
> tuned.

While a sysctl is an easy solution, I don't think we should go this route. A
sysctl is only settable by root, but such device specific sound tuning (or
more abstract: user changeable parts) should be made user configurable, e.g.
with a .ctl device in /dev and an ioctl interface (or maybe an extended ioctl
interface for /dev/dsp*). A sndctl application (or the mixer application in
case of switching to spdif output) can then change it without the need for
superuser privileges.

In case the user should be able to modify parts where he may cause a DoS
(e.g. because a setting results in allocating memory depending on the value
of the setting), a sysctl to limit the range of values makes sense
(additionally to sanity checking of the values in the kernel).

Bye,
Alexander.

-- 
http://www.Leidinger.net  Alexander @ Leidinger.net: PGP ID = B0063FE7
http://www.FreeBSD.org     netchild @ FreeBSD.org  : PGP ID = 72077137
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