From 74665de68e4ca432debe181c6cdfad4b482eacdc Mon Sep 17 00:00:00 2001
From: Wim Taymans <wtaymans@redhat.com>
Date: Tue, 31 Mar 2020 17:52:22 +0200
Subject: [PATCH] alsa-seq: keep track of last port

Keep track of the last port and only iterate until that port.
---
 spa/plugins/alsa/alsa-seq-source.c | 17 +++++++++++++----
 spa/plugins/alsa/alsa-seq.c        | 10 +++++-----
 spa/plugins/alsa/alsa-seq.h        |  1 +
 3 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/spa/plugins/alsa/alsa-seq-source.c b/spa/plugins/alsa/alsa-seq-source.c
index 9d09f09ef..26ebccd08 100644
--- a/spa/plugins/alsa/alsa-seq-source.c
+++ b/spa/plugins/alsa/alsa-seq-source.c
@@ -350,7 +350,7 @@ static struct seq_port *find_port(struct seq_state *state,
 		struct seq_stream *stream, const snd_seq_addr_t *addr)
 {
 	uint32_t i;
-	for (i = 0; i < MAX_PORTS; i++) {
+	for (i = 0; i < stream->last_port; i++) {
 		struct seq_port *port = &stream->ports[i];
 		if (port->valid &&
 		    port->addr.client == addr->client &&
@@ -369,14 +369,23 @@ static struct seq_port *alloc_port(struct seq_state *state, struct seq_stream *s
 			port->id = i;
 			port->direction = stream->direction;
 			port->valid = true;
+			if (stream->last_port < i + 1)
+				stream->last_port = i + 1;
 			return port;
 		}
 	}
 	return NULL;
 }
 
-static void free_port(struct seq_state *state, struct seq_port *port)
+static void free_port(struct seq_state *state, struct seq_stream *stream, struct seq_port *port)
 {
+	if (port->id + 1 == stream->last_port) {
+		int i;
+		for (i = stream->last_port - 1; i >= 0; i--)
+			if (!stream->ports[i].valid)
+				break;
+		stream->last_port = i + 1;
+	}
 	spa_node_emit_port_info(&state->hooks,
 			port->direction, port->id, NULL);
 	spa_zero(*port);
@@ -417,7 +426,7 @@ static void update_stream_port(struct seq_state *state, struct seq_stream *strea
 	if (info == NULL) {
 		spa_log_debug(state->log, "free port %d.%d", addr->client, addr->port);
 		if (port)
-			free_port(state, port);
+			free_port(state, stream, port);
 	} else {
 		if (port == NULL && (caps & stream->caps) == stream->caps) {
 			spa_log_debug(state->log, "new port %d.%d", addr->client, addr->port);
@@ -428,7 +437,7 @@ static void update_stream_port(struct seq_state *state, struct seq_stream *strea
 		} else if (port != NULL) {
 			if ((caps & stream->caps) != stream->caps) {
 				spa_log_debug(state->log, "free port %d.%d", addr->client, addr->port);
-				free_port(state, port);
+				free_port(state, stream, port);
 			}
 			else {
 				spa_log_debug(state->log, "update port %d.%d", addr->client, addr->port);
diff --git a/spa/plugins/alsa/alsa-seq.c b/spa/plugins/alsa/alsa-seq.c
index 58639a4f5..6a1621ea6 100644
--- a/spa/plugins/alsa/alsa-seq.c
+++ b/spa/plugins/alsa/alsa-seq.c
@@ -366,7 +366,7 @@ static struct seq_port *find_port(struct seq_state *state,
 		struct seq_stream *stream, const snd_seq_addr_t *addr)
 {
 	uint32_t i;
-	for (i = 0; i < MAX_PORTS; i++) {
+	for (i = 0; i < stream->last_port; i++) {
 		struct seq_port *port = &stream->ports[i];
 		if (port->valid &&
 		    port->addr.client == addr->client &&
@@ -460,7 +460,7 @@ static int process_recycle(struct seq_state *state)
 	struct seq_stream *stream = &state->streams[SPA_DIRECTION_OUTPUT];
 	uint32_t i;
 
-	for (i = 0; i < MAX_PORTS; i++) {
+	for (i = 0; i < stream->last_port; i++) {
 		struct seq_port *port = &stream->ports[i];
 		struct spa_io_buffers *io = port->io;
 
@@ -547,7 +547,7 @@ static int process_read(struct seq_state *state)
 	/* prepare a buffer on each port, some ports might have their
 	 * buffer filled above */
 	res = 0;
-	for (i = 0; i < MAX_PORTS; i++) {
+	for (i = 0; i < stream->last_port; i++) {
 		struct seq_port *port = &stream->ports[i];
 		struct spa_io_buffers *io = port->io;
 
@@ -599,7 +599,7 @@ static int process_write(struct seq_state *state)
 	uint32_t i;
 	int res = 0;
 
-	for (i = 0; i < MAX_PORTS; i++) {
+	for (i = 0; i < stream->last_port; i++) {
 		struct seq_port *port = &stream->ports[i];
 		struct spa_io_buffers *io = port->io;
 		struct buffer *buffer;
@@ -819,7 +819,7 @@ static void reset_buffers(struct seq_state *this, struct seq_port *port)
 static void reset_stream(struct seq_state *this, struct seq_stream *stream, bool active)
 {
 	uint32_t i;
-	for (i = 0; i < MAX_PORTS; i++) {
+	for (i = 0; i < stream->last_port; i++) {
 		struct seq_port *port = &stream->ports[i];
 		if (port->valid) {
 			reset_buffers(this, port);
diff --git a/spa/plugins/alsa/alsa-seq.h b/spa/plugins/alsa/alsa-seq.h
index aca7daaca..32e9b4697 100644
--- a/spa/plugins/alsa/alsa-seq.h
+++ b/spa/plugins/alsa/alsa-seq.h
@@ -94,6 +94,7 @@ struct seq_stream {
 	unsigned int caps;
 	snd_midi_event_t *codec;
 	struct seq_port ports[MAX_PORTS];
+	uint32_t last_port;
 };
 
 struct seq_conn {