adapter: Copy over GstMeta from the input buffers to the output

All functions that return a GstBuffer or a list of them will now copy
all GstMeta from the input buffers except for meta with GST_META_FLAG_POOLED
flag or "memory" tag.

This is similar to the existing behaviour that the caller can't assume
anything about the buffer flags, timestamps or other metadata. And it's
also the same that gst_adapter_take_buffer_fast() did before, and what
gst_adapter_take_buffer() did if part of the first buffer or the complete
first buffer was requested.

https://bugzilla.gnome.org/show_bug.cgi?id=742385

1 files changed, 53 insertions, 0 deletions

diff --git a/libs/gst/base/gstadapter.c b/libs/gst/base/gstadapter.c
index 7a1c7602e..891d3d40b 100644
--- a/libs/gst/base/gstadapter.c
+++ b/libs/gst/base/gstadapter.c
@@ -752,6 +752,9 @@ gst_adapter_take (GstAdapter * adapter, gsize nbytes)
  * The caller needs to explicitly set or unset flags that should be set or
  * unset.
  *
+ * This will also copy over all GstMeta of the input buffers except
+ * for meta with the %GST_META_FLAG_POOLED flag or with the "memory" tag.
+ *
  * This function can return buffer up to the return value of
  * gst_adapter_available() without making copies if possible.
  *
@@ -821,6 +824,37 @@ done:
   return buffer;
 }
 
+static gboolean
+foreach_metadata (GstBuffer * inbuf, GstMeta ** meta, gpointer user_data)
+{
+  GstBuffer *outbuf = user_data;
+  const GstMetaInfo *info = (*meta)->info;
+  gboolean do_copy = FALSE;
+
+  if (GST_META_FLAG_IS_SET (*meta, GST_META_FLAG_POOLED)) {
+    /* never call the transform_meta with pool private metadata */
+    GST_DEBUG ("not copying pooled metadata %s", g_type_name (info->api));
+    do_copy = FALSE;
+  } else if (gst_meta_api_type_has_tag (info->api, _gst_meta_tag_memory)) {
+    /* never call the transform_meta with memory specific metadata */
+    GST_DEBUG ("not copying memory specific metadata %s",
+        g_type_name (info->api));
+    do_copy = FALSE;
+  } else {
+    do_copy = TRUE;
+    GST_DEBUG ("copying metadata %s", g_type_name (info->api));
+  }
+
+  if (do_copy) {
+    GstMetaTransformCopy copy_data = { FALSE, 0, -1 };
+    GST_DEBUG ("copy metadata %s", g_type_name (info->api));
+    /* simply copy then */
+    info->transform_func (outbuf, *meta, inbuf,
+        _gst_meta_transform_copy, &copy_data);
+  }
+  return TRUE;
+}
+
 /**
  * gst_adapter_take_buffer:
  * @adapter: a #GstAdapter
@@ -838,6 +872,9 @@ done:
  * The caller needs to explicitly set or unset flags that should be set or
  * unset.
  *
+ * Since 1.6 this will also copy over all GstMeta of the input buffers except
+ * for meta with the %GST_META_FLAG_POOLED flag or with the "memory" tag.
+ *
  * Caller owns a reference to the returned buffer. gst_buffer_unref() after
  * usage.
  *
@@ -901,6 +938,22 @@ gst_adapter_take_buffer (GstAdapter * adapter, gsize nbytes)
 
   buffer = gst_buffer_new_wrapped (data, nbytes);
 
+  {
+    GSList *g;
+    GstBuffer *cur;
+    gsize read_offset = 0;
+
+    g = adapter->buflist;
+    while (g && read_offset < nbytes + adapter->skip) {
+      cur = g->data;
+
+      gst_buffer_foreach_meta (cur, foreach_metadata, buffer);
+      read_offset += gst_buffer_get_size (cur);
+
+      g = g_slist_next (g);
+    }
+  }
+
 done:
   gst_adapter_flush_unchecked (adapter, nbytes);