gl/bufferpool: add api for retrieving the configure gl allocation params

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/-/merge_requests/1071>

gst-libs/gst/gl/gstglbufferpool.c

@@ -379,6 +379,31 @@ gst_gl_buffer_pool_finalize (GObject * object)
   priv->gl_params = NULL;
 }
 
+/**
+ * gst_gl_buffer_pool_get_gl_allocation_params:
+ * @pool: the #GstGLBufferPool
+ *
+ * The returned #GstGLAllocationParams will by %NULL before the first successful
+ * call to gst_buffer_pool_set_config().  Subsequent successful calls to
+ * gst_buffer_pool_set_config() will cause this function to return a new
+ * #GstGLAllocationParams which may or may not contain the same information.
+ *
+ * Returns: (transfer full): a copy of the #GstGLAllocationParams being used by the @pool
+ *
+ * Since: 1.20
+ */
+GstGLAllocationParams *
+gst_gl_buffer_pool_get_gl_allocation_params (GstGLBufferPool * pool)
+{
+  g_return_val_if_fail (GST_IS_GL_BUFFER_POOL (pool), NULL);
+
+  if (pool->priv->gl_params)
+    return gst_gl_allocation_params_copy ((GstGLAllocationParams *) pool->
+        priv->gl_params);
+  else
+    return NULL;
+}
+
 /**
  * gst_buffer_pool_config_get_gl_allocation_params:
  * @config: a buffer pool config

gst-libs/gst/gl/gstglbufferpool.h

@@ -69,6 +69,9 @@ struct _GstGLBufferPoolClass
 GST_GL_API
 GstBufferPool *gst_gl_buffer_pool_new (GstGLContext * context);
 
+GST_GL_API
+GstGLAllocationParams * gst_gl_buffer_pool_get_gl_allocation_params        (GstGLBufferPool * pool);
+
 GST_GL_API
 GstGLAllocationParams * gst_buffer_pool_config_get_gl_allocation_params    (GstStructure * config);
 GST_GL_API