>Number:         13829
>Category:       kern
>Synopsis:       select/poll incorrect on audio devices (+fix)
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Aug 30 05:20:00 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     Zdenek Salvet
>Release:        1.5.1
>Organization:
Institute of Computer Science of Masaryk University, Brno, Czech Republic

>Environment:

>Description:
	rat does not work reliably and consumes 100% CPU time
	because it uses select() to manage
	non-blocking I/O to audio device and select() acts weird
>How-To-Repeat:
>Fix:
--- sys/dev/audio.c.orig        Mon Aug 20 17:07:23 2001
+++ sys/dev/audio.c     Mon Aug 20 17:18:16 2001
@@ -1777,14 +1777,13 @@
        DPRINTF(("audio_poll: events=0x%x mode=%d\n", events, sc->sc_mode));
 
        if (events & (POLLIN | POLLRDNORM))
-               if ((sc->sc_mode & AUMODE_PLAY) ?
-                   sc->sc_pr.stamp > sc->sc_wstamp : 
-                   sc->sc_rr.used > sc->sc_rr.usedlow)
+               if ((sc->sc_mode & AUMODE_RECORD) &&
+                   sc->sc_rr.used >= sc->sc_rr.blksize )
                        revents |= events & (POLLIN | POLLRDNORM);
 
        if (events & (POLLOUT | POLLWRNORM))
-               if (sc->sc_mode & AUMODE_RECORD ||
-                   sc->sc_pr.used <= sc->sc_pr.usedlow)
+               if ((sc->sc_mode & AUMODE_PLAY) &&
+                   sc->sc_pr.used <= sc->sc_pr.usedhigh)
                        revents |= events & (POLLOUT | POLLWRNORM);
 
        if (revents == 0) {

>Release-Note:
>Audit-Trail:
>Unformatted: