From fc5dc6de66bfc1e316f3f135c8e1139a23d8944b Mon Sep 17 00:00:00 2001
From: Wim Taymans <wim.taymans@gmail.com>
Date: Tue, 11 Oct 2005 12:58:44 +0000
Subject: [PATCH] gst/gstbin.*: Work on proper clock selection.

Original commit message from CVS:
* gst/gstbin.c: (gst_bin_init), (gst_bin_provide_clock_func),
(gst_bin_add_func), (gst_bin_remove_func), (gst_bin_recalc_state),
(gst_bin_change_state_func), (bin_bus_handler):
* gst/gstbin.h:
Work on proper clock selection.
---
 ChangeLog    |  8 ++++++++
 common       |  2 +-
 gst/gstbin.c | 39 +++++++++++++++++++++++++++++++++++----
 gst/gstbin.h |  3 +++
 4 files changed, 47 insertions(+), 5 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 08b1b11cf4..003adcd693 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2005-10-11  Wim Taymans  <wim@fluendo.com>
+
+	* gst/gstbin.c: (gst_bin_init), (gst_bin_provide_clock_func),
+	(gst_bin_add_func), (gst_bin_remove_func), (gst_bin_recalc_state),
+	(gst_bin_change_state_func), (bin_bus_handler):
+	* gst/gstbin.h:
+	Work on proper clock selection.
+
 2005-10-11  Edward Hervey  <edward@fluendo.com>
 
 	* libs/gst/controller/gstcontroller.c: (gst_controller_remove_properties_list): 
diff --git a/common b/common
index 54920e38c6..615cf4d450 160000
--- a/common
+++ b/common
@@ -1 +1 @@
-Subproject commit 54920e38c65eaf03ea52c21b14a6d104a56581a9
+Subproject commit 615cf4d4506ef1ffb1f600c434fced1fa26b0f44
diff --git a/gst/gstbin.c b/gst/gstbin.c
index 1f9bfa6925..bc14c6c0cc 100644
--- a/gst/gstbin.c
+++ b/gst/gstbin.c
@@ -289,6 +289,8 @@ gst_bin_init (GstBin * bin)
   bin->eosed = NULL;
   bin->polling = FALSE;
   bin->state_dirty = FALSE;
+  bin->provided_clock = NULL;
+  bin->clock_dirty = FALSE;
 
   /* Set up a bus for listening to child elements */
   bus = g_object_new (gst_bus_get_type (), NULL);
@@ -361,8 +363,11 @@ gst_bin_set_clock_func (GstElement * element, GstClock * clock)
  * The ref of the returned clock in increased so unref after usage.
  *
  * MT safe
- *
- * FIXME, clock selection is not correct here.
+ */
+/*
+ * FIXME, clock selection is not correct here. We should loop the
+ * elements in state order and pick the last clock we can get. This
+ * makes sure we get a clock from the source.
  */
 static GstClock *
 gst_bin_provide_clock_func (GstElement * element)
@@ -374,16 +379,32 @@ gst_bin_provide_clock_func (GstElement * element)
   bin = GST_BIN (element);
 
   GST_LOCK (bin);
+  if (!bin->clock_dirty)
+    goto not_dirty;
+
   for (children = bin->children; children; children = g_list_next (children)) {
     GstElement *child = GST_ELEMENT (children->data);
 
-    result = gst_element_provide_clock (child);
-    if (result)
+    if ((result = gst_element_provide_clock (child)))
       break;
   }
+  gst_object_replace ((GstObject **) & bin->provided_clock,
+      (GstObject *) result);
+  bin->clock_dirty = FALSE;
+  GST_DEBUG_OBJECT (bin, "provided new clock %p", result);
   GST_UNLOCK (bin);
 
   return result;
+
+not_dirty:
+  {
+    if ((result = bin->provided_clock))
+      gst_object_ref (result);
+    GST_DEBUG_OBJECT (bin, "returning old clock %p", result);
+    GST_UNLOCK (bin);
+
+    return result;
+  }
 }
 
 /* Check if the bin is EOS. We do this by scanning all sinks and
@@ -468,6 +489,11 @@ gst_bin_add_func (GstBin * bin, GstElement * element)
         elem_name);
     GST_FLAG_SET (bin, GST_ELEMENT_IS_SINK);
   }
+  if (gst_element_provides_clock (element)) {
+    GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin,
+        "element \"%s\" can provide a clock", elem_name);
+    bin->clock_dirty = TRUE;
+  }
 
   bin->children = g_list_prepend (bin->children, element);
   bin->numchildren++;
@@ -618,6 +644,11 @@ gst_bin_remove_func (GstBin * bin, GstElement * element)
       GST_FLAG_UNSET (bin, GST_ELEMENT_IS_SINK);
     }
   }
+  if (gst_element_provides_clock (element)) {
+    GST_CAT_DEBUG_OBJECT (GST_CAT_PARENTAGE, bin,
+        "element \"%s\" could provide a clock", elem_name);
+    bin->clock_dirty = TRUE;
+  }
   bin->state_dirty = TRUE;
   GST_UNLOCK (bin);
 
diff --git a/gst/gstbin.h b/gst/gstbin.h
index e90066fd2b..7d8a8425c2 100644
--- a/gst/gstbin.h
+++ b/gst/gstbin.h
@@ -95,6 +95,9 @@ struct _GstBin {
   gboolean	 polling;
   gboolean       state_dirty;
 
+  gboolean       clock_dirty;
+  GstClock	*provided_clock;
+
   /*< private >*/
   gpointer _gst_reserved[GST_PADDING];
 };