gst-libs/gst/app/gstappsrc.*: Add properties and methods to configure and retrieve the min and max latencies.

Original commit message from CVS:
* gst-libs/gst/app/gstappsrc.c: (gst_app_src_class_init),
(gst_app_src_init), (gst_app_src_set_property),
(gst_app_src_get_property), (gst_app_src_query),
(gst_app_src_set_latencies), (gst_app_src_set_latency),
(gst_app_src_get_latency), (gst_app_src_push_buffer_full):
* gst-libs/gst/app/gstappsrc.h:
Add properties and methods to configure and retrieve the min and max
latencies.

ChangeLog

@@ -1,3 +1,14 @@
+2008-12-29  Wim Taymans  <wim.taymans@collabora.co.uk>
+
+	* gst-libs/gst/app/gstappsrc.c: (gst_app_src_class_init),
+	(gst_app_src_init), (gst_app_src_set_property),
+	(gst_app_src_get_property), (gst_app_src_query),
+	(gst_app_src_set_latencies), (gst_app_src_set_latency),
+	(gst_app_src_get_latency), (gst_app_src_push_buffer_full):
+	* gst-libs/gst/app/gstappsrc.h:
+	Add properties and methods to configure and retrieve the min and max
+	latencies.
+
 2008-12-29  Wim Taymans  <wim.taymans@collabora.co.uk>
 
 	Patch by: Sebastian Pölsterl <sebp at k-d-w dot org>

gst-libs/gst/app/gstappsrc.c

@@ -124,6 +124,8 @@ enum
 #define DEFAULT_PROP_FORMAT        GST_FORMAT_BYTES
 #define DEFAULT_PROP_BLOCK         FALSE
 #define DEFAULT_PROP_IS_LIVE       FALSE
+#define DEFAULT_PROP_MIN_LATENCY   -1
+#define DEFAULT_PROP_MAX_LATENCY   -1
 
 enum
 {
@@ -135,7 +137,8 @@ enum
   PROP_FORMAT,
   PROP_BLOCK,
   PROP_IS_LIVE,
-
+  PROP_MIN_LATENCY,
+  PROP_MAX_LATENCY,
   PROP_LAST
 };
 
@@ -175,6 +178,9 @@ static void gst_app_src_set_property (GObject * object, guint prop_id,
 static void gst_app_src_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec);
 
+static void gst_app_src_set_latencies (GstAppSrc * appsrc,
+    gboolean do_min, guint64 min, gboolean do_max, guint64 max);
+
 static GstFlowReturn gst_app_src_create (GstBaseSrc * bsrc,
     guint64 offset, guint size, GstBuffer ** buf);
 static gboolean gst_app_src_start (GstBaseSrc * bsrc);
@@ -185,6 +191,8 @@ static gboolean gst_app_src_do_seek (GstBaseSrc * src, GstSegment * segment);
 static gboolean gst_app_src_is_seekable (GstBaseSrc * src);
 static gboolean gst_app_src_check_get_range (GstBaseSrc * src);
 static gboolean gst_app_src_do_get_size (GstBaseSrc * src, guint64 * size);
+static gboolean gst_app_src_query (GstBaseSrc * src, GstQuery * query);
+
 static GstFlowReturn gst_app_src_push_buffer_action (GstAppSrc * appsrc,
     GstBuffer * buffer);
 
@@ -306,6 +314,28 @@ gst_app_src_class_init (GstAppSrcClass * klass)
       g_param_spec_boolean ("is-live", "Is Live",
           "Whether to act as a live source",
           DEFAULT_PROP_IS_LIVE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+  /**
+   * GstAppSrc::min-latency
+   *
+   * The minimum latency of the source. A value of -1 will use the default
+   * latency calculations of #GstBaseSrc.
+   */
+  g_object_class_install_property (gobject_class, PROP_MIN_LATENCY,
+      g_param_spec_int64 ("min-latency", "Min Latency",
+          "The minimum latency (-1 = default)",
+          -1, G_MAXINT64, DEFAULT_PROP_MIN_LATENCY,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+  /**
+   * GstAppSrc::max-latency
+   *
+   * The maximum latency of the source. A value of -1 means an unlimited amout
+   * of latency.
+   */
+  g_object_class_install_property (gobject_class, PROP_MAX_LATENCY,
+      g_param_spec_int64 ("max-latency", "Max Latency",
+          "The maximum latency (-1 = unlimited)",
+          -1, G_MAXINT64, DEFAULT_PROP_MAX_LATENCY,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 
   /**
    * GstAppSrc::need-data:
@@ -395,6 +425,8 @@ gst_app_src_class_init (GstAppSrcClass * klass)
   basesrc_class->is_seekable = gst_app_src_is_seekable;
   basesrc_class->check_get_range = gst_app_src_check_get_range;
   basesrc_class->get_size = gst_app_src_do_get_size;
+  basesrc_class->get_size = gst_app_src_do_get_size;
+  basesrc_class->query = gst_app_src_query;
 
   klass->push_buffer = gst_app_src_push_buffer_action;
   klass->end_of_stream = gst_app_src_end_of_stream;
@@ -412,6 +444,8 @@ gst_app_src_init (GstAppSrc * appsrc, GstAppSrcClass * klass)
   appsrc->max_bytes = DEFAULT_PROP_MAX_BYTES;
   appsrc->format = DEFAULT_PROP_FORMAT;
   appsrc->block = DEFAULT_PROP_BLOCK;
+  appsrc->min_latency = DEFAULT_PROP_MIN_LATENCY;
+  appsrc->max_latency = DEFAULT_PROP_MAX_LATENCY;
 
   gst_base_src_set_live (GST_BASE_SRC (appsrc), DEFAULT_PROP_IS_LIVE);
 }
@@ -480,6 +514,14 @@ gst_app_src_set_property (GObject * object, guint prop_id,
       gst_base_src_set_live (GST_BASE_SRC (appsrc),
           g_value_get_boolean (value));
       break;
+    case PROP_MIN_LATENCY:
+      gst_app_src_set_latencies (appsrc, TRUE, g_value_get_int64 (value),
+          FALSE, -1);
+      break;
+    case PROP_MAX_LATENCY:
+      gst_app_src_set_latencies (appsrc, FALSE, -1, TRUE,
+          g_value_get_int64 (value));
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -522,6 +564,22 @@ gst_app_src_get_property (GObject * object, guint prop_id, GValue * value,
     case PROP_IS_LIVE:
       g_value_set_boolean (value, gst_base_src_is_live (GST_BASE_SRC (appsrc)));
       break;
+    case PROP_MIN_LATENCY:
+    {
+      guint64 min;
+
+      gst_app_src_get_latency (appsrc, &min, NULL);
+      g_value_set_int64 (value, min);
+      break;
+    }
+    case PROP_MAX_LATENCY:
+    {
+      guint64 max;
+
+      gst_app_src_get_latency (appsrc, &max, NULL);
+      g_value_set_int64 (value, max);
+      break;
+    }
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -635,6 +693,40 @@ gst_app_src_do_get_size (GstBaseSrc * src, guint64 * size)
   return TRUE;
 }
 
+static gboolean
+gst_app_src_query (GstBaseSrc * src, GstQuery * query)
+{
+  GstAppSrc *appsrc = GST_APP_SRC (src);
+  gboolean res;
+
+  switch (GST_QUERY_TYPE (query)) {
+    case GST_QUERY_LATENCY:
+    {
+      GstClockTime min, max;
+      gboolean live;
+
+      /* Query the parent class for the defaults */
+      res = gst_base_src_query_latency (src, &live, &min, &max);
+
+      /* overwrite with our values when we need to */
+      g_mutex_lock (appsrc->mutex);
+      if (appsrc->min_latency != -1)
+        min = appsrc->min_latency;
+      if (appsrc->max_latency != -1)
+        max = appsrc->max_latency;
+      g_mutex_unlock (appsrc->mutex);
+
+      gst_query_set_latency (query, live, min, max);
+      break;
+    }
+    default:
+      res = GST_BASE_SRC_CLASS (parent_class)->query (src, query);
+      break;
+  }
+
+  return res;
+}
+
 /* will be called in push mode */
 static gboolean
 gst_app_src_do_seek (GstBaseSrc * src, GstSegment * segment)
@@ -977,6 +1069,66 @@ gst_app_src_get_max_bytes (GstAppSrc * appsrc)
   return result;
 }
 
+static void
+gst_app_src_set_latencies (GstAppSrc * appsrc, gboolean do_min, guint64 min,
+    gboolean do_max, guint64 max)
+{
+  gboolean changed = FALSE;
+
+  g_mutex_lock (appsrc->mutex);
+  if (do_min && appsrc->min_latency != min) {
+    appsrc->min_latency = min;
+    changed = TRUE;
+  }
+  if (do_max && appsrc->max_latency != max) {
+    appsrc->max_latency = max;
+    changed = TRUE;
+  }
+  g_mutex_unlock (appsrc->mutex);
+
+  if (changed) {
+    GST_DEBUG_OBJECT (appsrc, "posting latency changed");
+    gst_element_post_message (GST_ELEMENT_CAST (appsrc),
+        gst_message_new_latency (GST_OBJECT_CAST (appsrc)));
+  }
+}
+
+/**
+ * gst_app_src_set_latency:
+ * @appsrc: a #GstAppSrc
+ * @min: the min latency
+ * @max: the min latency
+ *
+ * Configure the @min and @max latency in @src. If @min is set to -1, the
+ * default latency calculations for pseudo-live sources will be used.
+ */
+void
+gst_app_src_set_latency (GstAppSrc * appsrc, guint64 min, guint64 max)
+{
+  gst_app_src_set_latencies (appsrc, TRUE, min, TRUE, max);
+}
+
+/**
+ * gst_app_src_get_latency:
+ * @appsrc: a #GstAppSrc
+ * @min: the min latency
+ * @max: the min latency
+ *
+ * Retrieve the min and max latencies in @min and @max respectively.
+ */
+void
+gst_app_src_get_latency (GstAppSrc * appsrc, guint64 * min, guint64 * max)
+{
+  g_return_if_fail (GST_IS_APP_SRC (appsrc));
+
+  g_mutex_lock (appsrc->mutex);
+  if (min)
+    *min = appsrc->min_latency;
+  if (max)
+    *max = appsrc->max_latency;
+  g_mutex_unlock (appsrc->mutex);
+}
+
 static GstFlowReturn
 gst_app_src_push_buffer_full (GstAppSrc * appsrc, GstBuffer * buffer,
     gboolean steal_ref)

gst-libs/gst/app/gstappsrc.h

@@ -79,6 +79,9 @@ struct _GstAppSrc
   guint64 queued_bytes;
   guint64 offset;
   GstAppStreamType current_type;
+
+  guint64 min_latency;
+  guint64 max_latency;
 };
 
 struct _GstAppSrcClass
@@ -111,6 +114,9 @@ GstAppStreamType gst_app_src_get_stream_type  (GstAppSrc *appsrc);
 void             gst_app_src_set_max_bytes    (GstAppSrc *appsrc, guint64 max);
 guint64          gst_app_src_get_max_bytes    (GstAppSrc *appsrc);
 
+void             gst_app_src_set_latency      (GstAppSrc *appsrc, guint64 min, guint64 max);
+void             gst_app_src_get_latency      (GstAppSrc *appsrc, guint64 *min, guint64 *max);
+
 GstFlowReturn    gst_app_src_push_buffer      (GstAppSrc *appsrc, GstBuffer *buffer);
 GstFlowReturn    gst_app_src_end_of_stream    (GstAppSrc *appsrc);