Patch for xmms2 Dr. No to stabilize Jack Output and prevent xruns on track skipping.

stabilize-jack-output-on-trackskip-ver2.patch

diff --git a/src/include/xmms/xmms_outputplugin.h b/src/include/xmms/xmms_outputplugin.h
index 11016d0..768844d 100644
--- a/src/include/xmms/xmms_outputplugin.h
+++ b/src/include/xmms/xmms_outputplugin.h
@@ -311,6 +311,16 @@ void xmms_output_stream_type_add (xmms_output_t *output, ...);
 gint xmms_output_read (xmms_output_t *output, char *buffer, gint len);
 
 /**
+ * determine there is enough data in the ringbuffer to fill out a peroid
+ *
+ * @param output an output object
+ * @param len the number of bytes to read
+ * @return 0 yes, -1 no
+ */
+
+gint output_is_ready_for_period (xmms_output_t *output, gint len);
+
+/**
  * Set an error.
  *
  * When an error occurs in an asynchronous function, the error can be
diff --git a/src/plugins/jack/jack.c b/src/plugins/jack/jack.c
index 926fd54..87aea6d 100644
--- a/src/plugins/jack/jack.c
+++ b/src/plugins/jack/jack.c
@@ -146,6 +146,8 @@ xmms_jack_new (xmms_output_t *output)
 	                        jack_get_sample_rate (data->jack));
 
 	/* we should connect the ports here? */
+	
+	xmms_log_info ("Started Patched xmms2 jack output");
 
 	return TRUE;
 }
@@ -266,7 +268,12 @@ xmms_jack_process (jack_nframes_t frames, void *arg)
 			t = MIN (toread * CHANNELS * sizeof (xmms_samplefloat_t),
 			         sizeof (tbuf));
 
-			res = xmms_output_read (output, (gchar *)tbuf, t);
+			if (output_is_ready_for_period(output, t) == 0) {
+				res = xmms_output_read (output, (gchar *)tbuf, t);
+			} else {
+				/* xmms_log_info ("Not Enough Bits in the Ring Buffer, its going to be a silent period..."); */
+				break;
+			}
 
 			if (res <= 0) {
 				XMMS_DBG ("output_read returned %d", res);
diff --git a/src/xmms/output.c b/src/xmms/output.c
index 53c6d6d..18a862c 100644
--- a/src/xmms/output.c
+++ b/src/xmms/output.c
@@ -526,6 +526,18 @@ xmms_output_filler (void *arg)
 }
 
 gint
+output_is_ready_for_period(xmms_output_t *output, gint len)
+{
+
+  if (xmms_ringbuf_bytes_used(output->filler_buffer) >= len) {
+    return 0;
+  } else {
+    return -1;
+  }
+
+}
+
+gint
 xmms_output_read (xmms_output_t *output, char *buffer, gint len)
 {
 	gint ret;