Add the AUDIO_GETPOS ioctl() to fetch a snapshot of the 4 counters

returned by AUDIO_GETxOFFS and AUDIO_xERROR ioctls.

ok deraadt

3 files changed, 58 insertions, 7 deletions

diff --git a/share/man/man4/audio.4 b/share/man/man4/audio.4
index 2d8179a74c8..ae30267fc85 100644
--- a/share/man/man4/audio.4
+++ b/share/man/man4/audio.4
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: audio.4,v 1.67 2015/07/27 06:10:22 ratchov Exp $
+.\"	$OpenBSD: audio.4,v 1.68 2015/07/28 20:45:02 ratchov Exp $
 .\"	$NetBSD: audio.4,v 1.20 1998/05/28 17:27:15 augustss Exp $
 .\"
 .\" Copyright (c) 1996 The NetBSD Foundation, Inc.
@@ -28,7 +28,7 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: July 27 2015 $
+.Dd $Mdocdate: July 28 2015 $
 .Dt AUDIO 4
 .Os
 .Sh NAME
@@ -129,6 +129,7 @@ commands are supported on the sample devices:
 .Bl -tag -width Ds -compact
 .It Dv AUDIO_RERROR Fa "int *"
 .It Dv AUDIO_PERROR Fa "int *"
+Obsolete.
 These commands fetch the count of dropped input or output samples into
 the
 .Vt int *
@@ -194,6 +195,7 @@ The device can set playing and recording channel counts independently.
 .Pp
 .It Dv AUDIO_GETIOFFS Fa "audio_offset_t *"
 .It Dv AUDIO_GETOOFFS Fa "audio_offset_t *"
+Obsolete.
 These commands fetch the number of bytes played or recorded.
 The information is returned in the
 .Vt audio_offset
@@ -332,6 +334,37 @@ if the pause value is specified it will either pause
 or unpause the particular direction.
 In full-duplex the pause values for both directions must
 be equal.
+.Pp
+.It Dv AUDIO_GETPOS Fa "struct audio_pos *"
+Fetch an atomic snapshot of device timing information in the
+.Vt audio_pos
+structure.
+.Bd -literal
+struct audio_pos {
+	unsigned int play_pos;	/* total bytes played */
+	unsigned int play_xrun;	/* bytes of silence inserted */
+	unsigned int rec_pos;	/* total bytes recorded */
+	unsigned int rec_xrun;	/* bytes dropped */
+};
+.Ed
+.Pp
+The properties have the following meaning:
+.Bl -tag -width "play_xrun"
+.It Va play_pos
+Total number of bytes played by the device since playback started
+(a.k.a the device wall clock).
+.It Va play_xrun
+The number of bytes corresponding to silence played because
+.Xr write 2
+wasn't called fast enough.
+.It Va rec_pos
+Total number of bytes recorded by the device since recording started
+(a.k.a the device wall clock).
+.It Va rec_xrun
+The number of bytes dropped because
+.Xr read 2
+wasn't called fast enough.
+.El
 .El
 .Sh MIXER DEVICE
 The
diff --git a/sys/dev/audio.c b/sys/dev/audio.c
index 8506f88b0ee..29550f2be88 100644
--- a/sys/dev/audio.c
+++ b/sys/dev/audio.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: audio.c,v 1.134 2015/07/24 08:56:45 ratchov Exp $	*/
+/*	$OpenBSD: audio.c,v 1.135 2015/07/28 20:45:02 ratchov Exp $	*/
 /*
  * Copyright (c) 2015 Alexandre Ratchov <alex@caoua.org>
  *
@@ -66,9 +66,9 @@ struct audio_buf {
 	size_t start;			/* first byte used in the FIFO */
 	size_t used;			/* bytes used in the FIFO */
 	size_t blksz;			/* DMA block size */
-	unsigned long pos;		/* bytes transferred */
-	unsigned long xrun;		/* bytes lost by xruns */
 	struct selinfo sel;		/* to record & wakeup poll(2) */
+	unsigned int pos;		/* bytes transferred */
+	unsigned int xrun;		/* bytes lost by xruns */
 	int blocking;			/* read/write blocking */
 };
 
@@ -1298,7 +1298,7 @@ audio_drain(struct audio_softc *sc)
 
 	xrun = sc->play.xrun;
 	while (sc->play.xrun == xrun) {
-		DPRINTF("%s: drain: used = %zu, xrun = %ld\n",
+		DPRINTF("%s: drain: used = %zu, xrun = %d\n",
 		    DEVNAME(sc), sc->play.used, sc->play.xrun);
 
 		/*
@@ -1486,6 +1486,7 @@ int
 audio_ioctl(struct audio_softc *sc, unsigned long cmd, void *addr)
 {
 	struct audio_offset *ao;
+	struct audio_pos *ap;
 	int error = 0, fd;
 
 	/* block if quiesced */
@@ -1518,6 +1519,15 @@ audio_ioctl(struct audio_softc *sc, unsigned long cmd, void *addr)
 		ao->samples = sc->rec.pos;
 		mtx_leave(&audio_lock);
 		break;
+	case AUDIO_GETPOS:
+		mtx_enter(&audio_lock);
+		ap = (struct audio_pos *)addr;
+		ap->play_pos = sc->play.pos;
+		ap->play_xrun = sc->play.xrun;
+		ap->rec_pos = sc->rec.pos;
+		ap->rec_xrun = sc->rec.xrun;
+		mtx_leave(&audio_lock);
+		break;
 	case AUDIO_SETINFO:
 		error = audio_setinfo(sc, (struct audio_info *)addr);
 		break;
diff --git a/sys/sys/audioio.h b/sys/sys/audioio.h
index afbdd7a7a19..f93c1c45e56 100644
--- a/sys/sys/audioio.h
+++ b/sys/sys/audioio.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: audioio.h,v 1.22 2015/06/25 06:43:46 ratchov Exp $	*/
+/*	$OpenBSD: audioio.h,v 1.23 2015/07/28 20:45:02 ratchov Exp $	*/
 /*	$NetBSD: audioio.h,v 1.24 1998/08/13 06:28:41 mrg Exp $	*/
 
 /*
@@ -92,6 +92,13 @@ typedef struct audio_offset {
 	u_int	unused[2];
 } audio_offset_t;
 
+struct audio_pos {
+	unsigned int play_pos;	/* total bytes played */
+	unsigned int play_xrun;	/* bytes of silence inserted */
+	unsigned int rec_pos;	/* total bytes recorded */
+	unsigned int rec_xrun;	/* bytes dropped */
+};
+
 /*
  * Supported audio encodings
  */
@@ -141,6 +148,7 @@ typedef struct audio_encoding {
 #define AUDIO_GETIOFFS	_IOR('A', 32, struct audio_offset)
 #define AUDIO_GETOOFFS	_IOR('A', 33, struct audio_offset)
 #define AUDIO_GETPROPS	_IOR('A', 34, int)
+#define AUDIO_GETPOS	_IOR('A', 35, struct audio_pos)
 #define  AUDIO_PROP_FULLDUPLEX	0x01
 #define  AUDIO_PROP_MMAP	0x02
 #define  AUDIO_PROP_INDEPENDENT	0x04