add two new audio ioctls, AUDIO_GETPRINFO and AUDIO_GETRRINFO, and the

data structure these ioctls use, audio_bufinfo.

these ioctls return information about the play and record buffers
into the audio_bufinfo structure.

these are being added to aid in porting non-native audio applications
and libraries, and to fix issues in our OSS audio emulation.  these
ioctls exist only on OpenBSD and should not be used in code intended
for distribution.

ok ratchov

2 files changed, 54 insertions, 3 deletions

diff --git a/sys/dev/audio.c b/sys/dev/audio.c
index 80af5a51a97..82c4fb09693 100644
--- a/sys/dev/audio.c
+++ b/sys/dev/audio.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: audio.c,v 1.80 2007/09/24 19:45:03 ratchov Exp $	*/
+/*	$OpenBSD: audio.c,v 1.81 2007/10/03 21:49:13 jakemsr Exp $	*/
 /*	$NetBSD: audio.c,v 1.119 1999/11/09 16:50:47 augustss Exp $	*/
 
 /*
@@ -104,7 +104,7 @@ int	audio_blk_ms = AUDIO_BLK_MS;
 
 int	audiosetinfo(struct audio_softc *, struct audio_info *);
 int	audiogetinfo(struct audio_softc *, struct audio_info *);
-
+int	audiogetbufinfo(struct audio_softc *, struct audio_bufinfo *, int);
 int	audio_open(dev_t, struct audio_softc *, int, int, struct proc *);
 int	audio_close(dev_t, int, int, struct proc *);
 int	audio_read(dev_t, struct uio *, int);
@@ -1729,6 +1729,18 @@ audio_ioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
 		*(int *)addr = hw->get_props(sc->hw_hdl);
 		break;
 
+	case AUDIO_GETPRINFO:
+		DPRINTF(("AUDIO_GETPRINFO\n"));
+		error = audiogetbufinfo(sc, (struct audio_bufinfo *)addr,
+		    AUMODE_PLAY);
+		break;
+
+	case AUDIO_GETRRINFO:
+		DPRINTF(("AUDIO_GETRRINFO\n"));
+		error = audiogetbufinfo(sc, (struct audio_bufinfo *)addr,
+		    AUMODE_RECORD);
+		break;
+
 	default:
 		DPRINTF(("audio_ioctl: unknown ioctl\n"));
 		error = ENOTTY;
@@ -2924,6 +2936,35 @@ audiogetinfo(struct audio_softc *sc, struct audio_info *ai)
 	return (0);
 }
 
+int
+audiogetbufinfo(struct audio_softc *sc, struct audio_bufinfo *info, int mode)
+{
+	struct audio_ringbuffer *buf;
+	int factor;
+
+	factor = 1;
+	if (mode == AUMODE_PLAY) {
+		buf = &sc->sc_pr;
+		factor = sc->sc_pparams.factor;
+	} else {
+		buf = &sc->sc_rr;
+		factor = sc->sc_rparams.factor;
+	}
+
+	info->seek = buf->used / factor;
+	info->blksize = buf->blksize / factor;
+	if (buf->blksize != 0) {
+		info->hiwat = buf->usedhigh / buf->blksize;
+		info->lowat = buf->usedlow / buf->blksize;
+	} else {
+		info->hiwat = 0;
+		info->lowat = 0;
+	}
+
+	return (0);
+}
+
+
 /*
  * Mixer driver
  */
diff --git a/sys/sys/audioio.h b/sys/sys/audioio.h
index 07412e76218..c4925661d4d 100644
--- a/sys/sys/audioio.h
+++ b/sys/sys/audioio.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: audioio.h,v 1.17 2007/09/17 13:46:11 jakemsr Exp $	*/
+/*	$OpenBSD: audioio.h,v 1.18 2007/10/03 21:49:13 jakemsr Exp $	*/
 /*	$NetBSD: audioio.h,v 1.24 1998/08/13 06:28:41 mrg Exp $	*/
 
 /*
@@ -86,6 +86,14 @@ typedef struct audio_info audio_info_t;
 #define AUDIO_INITINFO(p) \
 	(void)memset((void *)(p), 0xff, sizeof(struct audio_info))
 
+struct audio_bufinfo {
+	u_int	blksize;	/* block size */
+	u_int	hiwat;		/* high water mark */
+	u_int	lowat;		/* low water mark */
+	u_int	seek;		/* current position */
+};
+typedef struct audio_bufinfo audio_bufinfo_t;
+
 /*
  * Parameter for the AUDIO_GETDEV ioctl to determine current
  * audio devices.
@@ -183,6 +191,8 @@ typedef struct audio_encoding {
 #define  AUDIO_PROP_FULLDUPLEX	0x01
 #define  AUDIO_PROP_MMAP	0x02
 #define  AUDIO_PROP_INDEPENDENT	0x04
+#define AUDIO_GETPRINFO	_IOR('A', 35, struct audio_bufinfo)
+#define AUDIO_GETRRINFO	_IOR('A', 36, struct audio_bufinfo)
 
 /*
  * Mixer device