spa: improve draining

Make a new DRAINED status.
Place the DRAINED status on an input IO when a stream is out of
buffers and draining.
All nodes that don't have HAVE_DATA on the input io need to copy
it to the output io and return the status. This makes sure the
DRAINED is forwarded and nodes return DRAINED from _process()
DRAINED on the resampler flushes out the last queued samples and then
forwards the DRAINED in the next iteration.
Emit a new drained signal from the context when a node returns
DRAINED. Use this to trigger the drained signal in the stream.

spa/include/spa/node/io.h

@@ -77,6 +77,9 @@ enum spa_io_type {
  * If status is SPA_STATUS_STOPPED, some error occured on the
  * port.
  *
+ * If status is SPA_STATUS_DRAINED, data from the io area was
+ * used to drain.
+ *
  * Status can also be a negative errno value to indicate errors.
  * such as:
  * -EINVAL: buffer_id is invalid
@@ -87,6 +90,7 @@ struct spa_io_buffers {
 #define SPA_STATUS_NEED_DATA		(1<<0)
 #define SPA_STATUS_HAVE_DATA		(1<<1)
 #define SPA_STATUS_STOPPED		(1<<2)
+#define SPA_STATUS_DRAINED		(1<<3)
 	int32_t status;			/**< the status code */
 	uint32_t buffer_id;		/**< a buffer id */
 };

spa/plugins/audioconvert/audioadapter.c

@@ -865,7 +865,7 @@ impl_node_port_reuse_buffer(void *object, uint32_t port_id, uint32_t buffer_id)
 static int impl_node_process(void *object)
 {
 	struct impl *this = object;
-	int status;
+	int status = 0;
 
 	spa_log_trace_fp(this->log, "%p: process convert:%u master:%d",
 			this, this->use_converter, this->master);
@@ -875,22 +875,17 @@ static int impl_node_process(void *object)
 			status = spa_node_process(this->convert);
 	}
 
-	status = spa_node_process(this->follower);
+	if (status >= 0)
+		status = spa_node_process(this->follower);
 
 	if (this->direction == SPA_DIRECTION_OUTPUT &&
 	    !this->master && this->use_converter) {
-		while (true) {
+		while (status >= 0) {
 			status = spa_node_process(this->convert);
-			if (status & SPA_STATUS_HAVE_DATA)
+			if (status & (SPA_STATUS_HAVE_DATA | SPA_STATUS_DRAINED))
 				break;
-
+			if (status & SPA_STATUS_NEED_DATA)
-			if (status & SPA_STATUS_NEED_DATA) {
 				status = spa_node_process(this->follower);
-				if (!(status & SPA_STATUS_HAVE_DATA)) {
-					spa_node_call_xrun(&this->callbacks, 0, 0, NULL);
-					break;
-				}
-			}
 		}
 	}
 	spa_log_trace_fp(this->log, "%p: process status:%d", this, status);

spa/plugins/audioconvert/audioconvert.c

@@ -1084,7 +1084,7 @@ static int impl_node_process(void *object)
 			if (SPA_UNLIKELY(i == 0))
 				res |= r & SPA_STATUS_NEED_DATA;
 			if (SPA_UNLIKELY(i == this->n_nodes-1))
-				res |= r & SPA_STATUS_HAVE_DATA;
+				res |= r & (SPA_STATUS_HAVE_DATA | SPA_STATUS_DRAINED);
 		}
 		if (res & SPA_STATUS_HAVE_DATA)
 			break;

spa/plugins/audioconvert/channelmix.c

@@ -864,15 +864,13 @@ static int impl_node_process(void *object)
 
 	if (SPA_UNLIKELY(outio->status == SPA_STATUS_HAVE_DATA))
 		return SPA_STATUS_HAVE_DATA;
-
-	if (SPA_UNLIKELY(inio->status != SPA_STATUS_HAVE_DATA))
-		return SPA_STATUS_NEED_DATA;
-
 	/* recycle */
 	if (SPA_LIKELY(outio->buffer_id < outport->n_buffers)) {
 		recycle_buffer(this, outio->buffer_id);
 		outio->buffer_id = SPA_ID_INVALID;
 	}
+	if (SPA_UNLIKELY(inio->status != SPA_STATUS_HAVE_DATA))
+		return outio->status = inio->status;
 
 	if (SPA_UNLIKELY(inio->buffer_id >= inport->n_buffers))
 		return inio->status = -EINVAL;

spa/plugins/audioconvert/fmtconvert.c

@@ -844,7 +844,8 @@ static int impl_node_process(void *object)
 		outio->buffer_id = SPA_ID_INVALID;
 	}
 	if (SPA_UNLIKELY(inio->status != SPA_STATUS_HAVE_DATA))
-		return SPA_STATUS_NEED_DATA;
+		return outio->status = inio->status;
+
 	if (SPA_UNLIKELY(inio->buffer_id >= inport->n_buffers))
 		return inio->status = -EINVAL;
 

spa/plugins/audioconvert/resample.c

@@ -118,6 +118,7 @@ struct impl {
 	int mode;
 	unsigned int started:1;
 	unsigned int peaks:1;
+	unsigned int drained:1;
 
 	struct resample resample;
 };
@@ -723,6 +724,7 @@ static int impl_node_process(void *object)
 	void **dst_datas;
 	bool flush_out = false;
 	bool flush_in = false;
+	bool draining = false;
 
 	spa_return_val_if_fail(this != NULL, -EINVAL);
 
@@ -741,15 +743,18 @@ static int impl_node_process(void *object)
 
 	if (SPA_UNLIKELY(outio->status == SPA_STATUS_HAVE_DATA))
 		return SPA_STATUS_HAVE_DATA;
-
-	if (SPA_UNLIKELY(inio->status != SPA_STATUS_HAVE_DATA))
-		return SPA_STATUS_NEED_DATA;
-
 	/* recycle */
 	if (SPA_LIKELY(outio->buffer_id < outport->n_buffers)) {
 		recycle_buffer(this, outio->buffer_id);
 		outio->buffer_id = SPA_ID_INVALID;
 	}
+	if (SPA_UNLIKELY(inio->status != SPA_STATUS_HAVE_DATA)) {
+		if (inio->status != SPA_STATUS_DRAINED || this->drained)
+			return outio->status = inio->status;
+
+		inio->buffer_id = 0;
+		inport->buffers[0].outbuf->datas[0].chunk->size = 0;
+	}
 
 	if (SPA_UNLIKELY(inio->buffer_id >= inport->n_buffers))
 		return inio->status = -EINVAL;
@@ -784,7 +789,7 @@ static int impl_node_process(void *object)
 		size = sb->datas[0].maxsize;
 		memset(sb->datas[0].data, 0, size);
 		inport->offset = 0;
-		flush_in = true;
+		flush_in = draining = true;
 	}
 
 	if (this->io_rate_match) {
@@ -829,18 +834,19 @@ static int impl_node_process(void *object)
 	if (inport->offset >= size || flush_in) {
 		inio->status = SPA_STATUS_NEED_DATA;
 		inport->offset = 0;
-		SPA_FLAG_SET(res, SPA_STATUS_NEED_DATA);
+		SPA_FLAG_SET(res, inio->status);
-		spa_log_trace_fp(this->log, NAME " %p: return input buffer", this);
+		spa_log_trace_fp(this->log, NAME " %p: return input buffer of size %d", this, size);
 	}
 
 	outport->offset += out_len * sizeof(float);
 	if (outport->offset > 0 && (outport->offset >= maxsize || flush_out)) {
 		outio->status = SPA_STATUS_HAVE_DATA;
 		outio->buffer_id = dbuf->id;
+		spa_log_trace_fp(this->log, NAME " %p: have output buffer of size %d", this, outport->offset);
 		dequeue_buffer(this, dbuf);
 		outport->offset = 0;
+		this->drained = draining;
 		SPA_FLAG_SET(res, SPA_STATUS_HAVE_DATA);
-		spa_log_trace_fp(this->log, NAME " %p: have output buffer", this);
 	}
 	if (out_len == 0 && this->peaks) {
 		outio->status = SPA_STATUS_HAVE_DATA;

spa/plugins/audioconvert/splitter.c

@@ -860,7 +860,7 @@ static int impl_node_process(void *object)
 			inio, inio->status, inio->buffer_id);
 
 	if (SPA_UNLIKELY(inio->status != SPA_STATUS_HAVE_DATA))
-		return SPA_STATUS_NEED_DATA;
+		return inio->status;
 
 	if (SPA_UNLIKELY(inio->buffer_id >= inport->n_buffers))
 		return inio->status = -EINVAL;

src/pipewire/impl-node.c

@@ -906,6 +906,9 @@ static inline int process_node(void *data)
 	} else {
 		resume_node(this, status);
 	}
+	if (status & SPA_STATUS_DRAINED) {
+		pw_context_driver_emit_drained(this->context, this);
+	}
 	return 0;
 }
 

src/pipewire/private.h

@@ -235,6 +235,7 @@ pw_core_resource_errorf(struct pw_resource *resource, uint32_t id, int seq,
 #define pw_context_driver_emit_xrun(c,n)	pw_context_driver_emit(c, xrun, 0, n)
 #define pw_context_driver_emit_incomplete(c,n)	pw_context_driver_emit(c, incomplete, 0, n)
 #define pw_context_driver_emit_timeout(c,n)	pw_context_driver_emit(c, timeout, 0, n)
+#define pw_context_driver_emit_drained(c,n)	pw_context_driver_emit(c, drained, 0, n)
 
 struct pw_context_driver_events {
 #define PW_VERSION_CONTEXT_DRIVER_EVENTS	0
@@ -248,6 +249,8 @@ struct pw_context_driver_events {
 	void (*incomplete) (void *data, struct pw_impl_node *node);
 	/** The driver got a sync timeout */
 	void (*timeout) (void *data, struct pw_impl_node *node);
+	/** a node drained */
+	void (*drained) (void *data, struct pw_impl_node *node);
 };
 
 #define pw_registry_resource(r,m,v,...) pw_resource_call(r, struct pw_registry_events,m,v,##__VA_ARGS__)

src/pipewire/stream.c

@@ -331,7 +331,6 @@ do_call_drained(struct spa_loop *loop,
 	struct pw_stream *stream = &impl->this;
 	pw_log_trace(NAME" %p: drained", stream);
 	pw_stream_emit_drained(stream);
-	impl->draining = false;
 	return 0;
 }
 
@@ -765,8 +764,7 @@ again:
 	pw_log_trace(NAME" %p: process out status:%d id:%d ticks:%"PRIu64" delay:%"PRIi64, stream,
 			io->status, io->buffer_id, impl->time.ticks, impl->time.delay);
 
-	res = 0;
+	if ((res = io->status) != SPA_STATUS_HAVE_DATA) {
-	if (io->status != SPA_STATUS_HAVE_DATA) {
 		/* recycle old buffer */
 		if ((b = get_buffer(stream, io->buffer_id)) != NULL) {
 			pw_log_trace(NAME" %p: recycle buffer %d", stream, b->id);
@@ -776,20 +774,17 @@ again:
 		/* pop new buffer */
 		if ((b = pop_queue(impl, &impl->queued)) != NULL) {
 			io->buffer_id = b->id;
-			io->status = SPA_STATUS_HAVE_DATA;
+			res = io->status = SPA_STATUS_HAVE_DATA;
 			pw_log_trace(NAME" %p: pop %d %p", stream, b->id, io);
+		} else if (impl->draining) {
+			impl->drained = true;
+			io->buffer_id = SPA_ID_INVALID;
+			res = io->status = SPA_STATUS_DRAINED;
+			pw_log_trace(NAME" %p: draining", stream);
 		} else {
 			io->buffer_id = SPA_ID_INVALID;
-			io->status = SPA_STATUS_NEED_DATA;
+			res = io->status = SPA_STATUS_NEED_DATA;
 			pw_log_trace(NAME" %p: no more buffers %p", stream, io);
-			if (impl->draining && !impl->drained) {
-				b = pop_queue(impl, &impl->dequeued);
-				io->buffer_id = b->id;
-				io->status = SPA_STATUS_HAVE_DATA;
-				b->this.buffer->datas[0].chunk->size = 0;
-				pw_log_trace(NAME" %p: drain buffer %d", stream, b->id);
-				impl->drained = true;
-			}
 		}
 	}
 
@@ -803,7 +798,6 @@ again:
 	}
 	copy_position(impl, impl->queued.outcount);
 
-	res = io->status;
 	pw_log_trace(NAME" %p: res %d", stream, res);
 
 	return res;
@@ -1044,7 +1038,7 @@ static const struct pw_core_events core_events = {
 	.error = on_core_error,
 };
 
-static void context_xrun(void *data, struct pw_impl_node *node)
+static void context_drained(void *data, struct pw_impl_node *node)
 {
 	struct stream *impl = data;
 	if (impl->node != node)
@@ -1055,7 +1049,7 @@ static void context_xrun(void *data, struct pw_impl_node *node)
 
 static const struct pw_context_driver_events context_events = {
 	PW_VERSION_CONTEXT_DRIVER_EVENTS,
-	.xrun = context_xrun,
+	.drained = context_drained,
 };
 
 static struct stream *