do GETBLKSIZE after setting bitrate, sample size, and channels

b/c the optimal fragment size depends on these settings, but also
GEBLKSIZE causes the fragment size to be set (which cannot be changed
w/o closing and reopening the device).
This fixes a problem a user was having with oss emu10k1 driver where
libao app's were skipping.


git-svn-id: http://svn.xiph.org/trunk/ao@5919 0101bb08-14d6-0310-b084-bc0e0c8e3800

src/plugins/oss/ao_oss.c

@@ -220,16 +220,6 @@ int ao_plugin_open(ao_device *device, ao_sample_format *format)
 
 	/* Now set all of the parameters */
 
-	internal->buf_size = -1;
-	if ((ioctl(internal->fd,SNDCTL_DSP_GETBLKSIZE,
-				&(internal->buf_size)) < 0) ||
-			internal->buf_size<=0 )
-	{
-		fprintf(stderr, "libao - OSS cannot get buffer size for "
-				" device\n");
-		goto ERR;
-	}
-
 	switch (format->channels)
 	{
 	case 1: tmp = 0;
@@ -279,6 +269,17 @@ int ao_plugin_open(ao_device *device, ao_sample_format *format)
 		goto ERR;
 	}
 
+	/* this calculates and sets the fragment size */
+	internal->buf_size = -1;
+	if ((ioctl(internal->fd,SNDCTL_DSP_GETBLKSIZE,
+				&(internal->buf_size)) < 0) ||
+			internal->buf_size<=0 )
+	{
+		fprintf(stderr, "libao - OSS cannot get buffer size for "
+				" device\n");
+		goto ERR;
+	}
+
 	return 1; /* Open successful */
 
  ERR: