From: Antonio Ospite <ao2@ao2.it>
Date: Mon, 2 Oct 2017 20:33:35 +0000 (+0200)
Subject: Expand snd_seq_create_simple_port() and use a queue to timestamp events
X-Git-Url: https://git.ao2.it/gst-aseq-appsrc.git/commitdiff_plain/e01610203967b299c3dcb06c957657d4f8430df9?ds=inline

Expand snd_seq_create_simple_port() and use a queue to timestamp events

Events are timestamped with a real-time value representing the time
passed since the queue timer was started.

The timestamp is not used just yet.
---

diff --git a/gst-aseq-appsrc.c b/gst-aseq-appsrc.c
index 506409e..1577ebf 100644
--- a/gst-aseq-appsrc.c
+++ b/gst-aseq-appsrc.c
@@ -51,6 +51,7 @@ struct _App
   GMainLoop *loop;
 
   snd_seq_t *seq;
+  int queue;
   int port_count;
   snd_seq_addr_t *seq_ports;
   snd_midi_event_t *parser;
@@ -143,17 +144,52 @@ out_free_ports_list:
 }
 
 static int
+start_queue_timer (snd_seq_t *seq, int queue)
+{
+  int ret;
+
+  ret = snd_seq_start_queue (seq, queue, NULL);
+  if (ret < 0) {
+    GST_ERROR ("Timer event output error: %s\n", snd_strerror (ret));
+    return ret;
+  }
+
+  ret = snd_seq_drain_output (seq);
+  if (ret < 0)
+    GST_ERROR ("Drain output error: %s\n", snd_strerror (ret));
+
+  return ret;
+}
+
+static int
 create_port (App * app)
 {
+  snd_seq_port_info_t *pinfo;
   int ret;
 
-  ret = snd_seq_create_simple_port (app->seq, DEFAULT_CLIENT_NAME,
-      SND_SEQ_PORT_CAP_WRITE |
-      SND_SEQ_PORT_CAP_SUBS_WRITE,
-      SND_SEQ_PORT_TYPE_MIDI_GENERIC | SND_SEQ_PORT_TYPE_APPLICATION);
+  snd_seq_port_info_alloca (&pinfo);
+  snd_seq_port_info_set_name (pinfo, DEFAULT_CLIENT_NAME);
+  snd_seq_port_info_set_type (pinfo, SND_SEQ_PORT_TYPE_MIDI_GENERIC | SND_SEQ_PORT_TYPE_APPLICATION);
+  snd_seq_port_info_set_capability (pinfo, SND_SEQ_PORT_CAP_WRITE | SND_SEQ_PORT_CAP_SUBS_WRITE);
+
+  ret = snd_seq_alloc_queue (app->seq);
+  if (ret < 0) {
+    GST_ERROR ("Cannot allocate queue: %s\n", snd_strerror (ret));
+    return ret;
+  }
+
+  app->queue = ret;
+
+  snd_seq_port_info_set_timestamping (pinfo, 1);
+  snd_seq_port_info_set_timestamp_real (pinfo, 1);
+  snd_seq_port_info_set_timestamp_queue (pinfo, app->queue);
+
+  ret = snd_seq_create_port (app->seq, pinfo);
   if (ret < 0)
     GST_ERROR ("Cannot create port - %s", snd_strerror (ret));
 
+  ret = start_queue_timer (app->seq, app->queue);
+
   return ret;
 }