diff --git a/src/lib.rs b/src/lib.rs
index a49591cb..236fa08a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -31,10 +31,10 @@ pub mod rshttpsrc;
 pub mod rsfilesink;
 
 use utils::*;
-use rssource::Source;
+use rssource::{Source, SourceController};
 use rsfilesrc::FileSrc;
 use rshttpsrc::HttpSrc;
-use rssink::Sink;
+use rssink::{Sink, SinkController};
 use rsfilesink::FileSink;
 
 use std::os::raw::c_void;
@@ -49,7 +49,8 @@ extern "C" {
                               classification: *const c_char,
                               author: *const c_char,
                               rank: i32,
-                              create_instance: extern "C" fn() -> *mut Box<Source>,
+                              create_instance: extern "C" fn(controller: SourceController)
+                                                             -> *mut Box<Source>,
                               protocols: *const c_char,
                               push_only: GBoolean)
                               -> GBoolean;
@@ -63,7 +64,8 @@ extern "C" {
                             classification: *const c_char,
                             author: *const c_char,
                             rank: i32,
-                            create_instance: extern "C" fn() -> *mut Box<Sink>,
+                            create_instance: extern "C" fn(controller: SinkController)
+                                                           -> *mut Box<Sink>,
                             protocols: *const c_char)
                             -> GBoolean;
 }
diff --git a/src/rsfilesink.rs b/src/rsfilesink.rs
index 9ad19121..a6d2c4b2 100644
--- a/src/rsfilesink.rs
+++ b/src/rsfilesink.rs
@@ -28,6 +28,7 @@ use rssink::*;
 
 #[derive(Debug)]
 pub struct FileSink {
+    controller: SinkController,
     location: Mutex<Option<PathBuf>>,
     file: Option<File>,
     position: u64,
@@ -37,19 +38,17 @@ unsafe impl Sync for FileSink {}
 unsafe impl Send for FileSink {}
 
 impl FileSink {
-    fn new() -> FileSink {
+    fn new(controller: SinkController) -> FileSink {
         FileSink {
+            controller: controller,
             location: Mutex::new(None),
             file: None,
             position: 0,
         }
     }
 
-    fn new_source() -> Box<Sink> {
-        Box::new(FileSink::new())
-    }
-    pub extern "C" fn new_ptr() -> *mut Box<Sink> {
-        let instance = Box::new(FileSink::new_source());
+    pub extern "C" fn new_ptr(controller: SinkController) -> *mut Box<Sink> {
+        let instance: Box<Box<Sink>> = Box::new(Box::new(FileSink::new(controller)));
         return Box::into_raw(instance);
     }
 }
diff --git a/src/rsfilesrc.rs b/src/rsfilesrc.rs
index 2a098f22..fc859b28 100644
--- a/src/rsfilesrc.rs
+++ b/src/rsfilesrc.rs
@@ -29,6 +29,7 @@ use rssource::*;
 
 #[derive(Debug)]
 pub struct FileSrc {
+    controller: SourceController,
     location: Mutex<Option<PathBuf>>,
     file: Option<File>,
     position: u64,
@@ -38,19 +39,17 @@ unsafe impl Sync for FileSrc {}
 unsafe impl Send for FileSrc {}
 
 impl FileSrc {
-    fn new() -> FileSrc {
+    fn new(controller: SourceController) -> FileSrc {
         FileSrc {
+            controller: controller,
             location: Mutex::new(None),
             file: None,
             position: 0,
         }
     }
 
-    fn new_source() -> Box<Source> {
-        Box::new(FileSrc::new())
-    }
-    pub extern "C" fn new_ptr() -> *mut Box<Source> {
-        let instance = Box::new(FileSrc::new_source());
+    pub extern "C" fn new_ptr(controller: SourceController) -> *mut Box<Source> {
+        let instance: Box<Box<Source>> = Box::new(Box::new(FileSrc::new(controller)));
         return Box::into_raw(instance);
     }
 }
diff --git a/src/rshttpsrc.rs b/src/rshttpsrc.rs
index d4255fab..cf7cffb0 100644
--- a/src/rshttpsrc.rs
+++ b/src/rshttpsrc.rs
@@ -32,6 +32,7 @@ use rssource::*;
 
 #[derive(Debug)]
 pub struct HttpSrc {
+    controller: SourceController,
     url: Mutex<Option<Url>>,
     client: Client,
     response: Option<Response>,
@@ -46,8 +47,9 @@ unsafe impl Sync for HttpSrc {}
 unsafe impl Send for HttpSrc {}
 
 impl HttpSrc {
-    fn new() -> HttpSrc {
+    fn new(controller: SourceController) -> HttpSrc {
         HttpSrc {
+            controller: controller,
             url: Mutex::new(None),
             client: Client::new(),
             response: None,
@@ -59,11 +61,8 @@ impl HttpSrc {
         }
     }
 
-    fn new_source() -> Box<Source> {
-        Box::new(HttpSrc::new())
-    }
-    pub extern "C" fn new_ptr() -> *mut Box<Source> {
-        let instance = Box::new(HttpSrc::new_source());
+    pub extern "C" fn new_ptr(controller: SourceController) -> *mut Box<Source> {
+        let instance: Box<Box<Source>> = Box::new(Box::new(HttpSrc::new(controller)));
         return Box::into_raw(instance);
     }
 
diff --git a/src/rssink.c b/src/rssink.c
index 3353b0c1..24973ca5 100644
--- a/src/rssink.c
+++ b/src/rssink.c
@@ -29,13 +29,14 @@ typedef struct
   gchar *description;
   gchar *classification;
   gchar *author;
-  void *(*create_instance) (void);
+  void *create_instance;
   gchar **protocols;
 } ElementData;
 static GHashTable *sinks;
 
 /* Declarations for Rust code */
 extern gboolean sinks_register (void *plugin);
+extern void *sink_new (GstRsSink * sink, void *create_instance);
 extern GstFlowReturn sink_render (void *filesink, void *data, size_t data_len);
 extern gboolean sink_set_uri (void *filesink, const char *uri);
 extern char *sink_get_uri (void *filesink);
@@ -118,7 +119,7 @@ gst_rs_sink_init (GstRsSink * sink, GstRsSinkClass * klass)
 
   gst_base_sink_set_sync (GST_BASE_SINK (sink), FALSE);
 
-  sink->instance = data->create_instance ();
+  sink->instance = sink_new (sink, data->create_instance);
 }
 
 static void
@@ -263,7 +264,7 @@ gboolean
 gst_rs_sink_register (GstPlugin * plugin, const gchar * name,
     const gchar * long_name, const gchar * description,
     const gchar * classification, const gchar * author, GstRank rank,
-    void *(*create_instance) (void), const gchar * protocols)
+    void *create_instance, const gchar * protocols)
 {
   GTypeInfo type_info = {
     sizeof (GstRsSinkClass),
diff --git a/src/rssink.rs b/src/rssink.rs
index 5d342d2b..18cb5074 100644
--- a/src/rssink.rs
+++ b/src/rssink.rs
@@ -17,6 +17,7 @@
 //  Boston, MA 02110-1301, USA.
 
 use libc::c_char;
+use std::os::raw::c_void;
 use std::ffi::{CStr, CString};
 use std::slice;
 use std::ptr;
@@ -26,6 +27,17 @@ use url::Url;
 
 use utils::*;
 
+#[derive(Debug)]
+pub struct SinkController {
+    sink: *mut c_void,
+}
+
+impl SinkController {
+    fn new(sink: *mut c_void) -> SinkController {
+        SinkController { sink: sink }
+    }
+}
+
 pub trait Sink: Sync + Send {
     // Called from any thread at any time
     fn set_uri(&mut self, uri: Option<Url>) -> bool;
@@ -37,6 +49,14 @@ pub trait Sink: Sync + Send {
     fn render(&mut self, data: &[u8]) -> GstFlowReturn;
 }
 
+#[no_mangle]
+pub extern "C" fn sink_new(sink: *mut c_void,
+                           create_instance: extern "C" fn(controller: SinkController)
+                                                          -> *mut Box<Sink>)
+                           -> *mut Box<Sink> {
+    create_instance(SinkController::new(sink))
+}
+
 #[no_mangle]
 pub extern "C" fn sink_drop(ptr: *mut Box<Sink>) {
     unsafe { Box::from_raw(ptr) };
diff --git a/src/rssource.c b/src/rssource.c
index fed3f837..bb1f3901 100644
--- a/src/rssource.c
+++ b/src/rssource.c
@@ -27,13 +27,14 @@ typedef struct
   gchar *description;
   gchar *classification;
   gchar *author;
-  void *(*create_instance) (void);
+  void *create_instance;
   gchar **protocols;
 } ElementData;
 static GHashTable *sources;
 
 /* Declarations for Rust code */
 extern gboolean sources_register (void *plugin);
+extern void *source_new (GstRsSrc * source, void *create_instance);
 extern void source_drop (void *source);
 extern GstFlowReturn source_fill (void *source, uint64_t offset, void *data,
     size_t * data_len);
@@ -127,7 +128,7 @@ gst_rs_src_init (GstRsSrc * src, GstRsSrcClass * klass)
 
   gst_base_src_set_blocksize (GST_BASE_SRC (src), 4096);
 
-  src->instance = data->create_instance ();
+  src->instance = source_new (src, data->create_instance);
 }
 
 static void
@@ -308,8 +309,7 @@ gboolean
 gst_rs_source_register (GstPlugin * plugin, const gchar * name,
     const gchar * long_name, const gchar * description,
     const gchar * classification, const gchar * author, GstRank rank,
-    void *(*create_instance) (void), const gchar * protocols,
-    gboolean push_only)
+    void *create_instance, const gchar * protocols, gboolean push_only)
 {
   GTypeInfo type_info = {
     sizeof (GstRsSrcClass),
diff --git a/src/rssource.rs b/src/rssource.rs
index aab975e9..4d955765 100644
--- a/src/rssource.rs
+++ b/src/rssource.rs
@@ -16,6 +16,7 @@
 //  Boston, MA 02110-1301, USA.
 
 use libc::c_char;
+use std::os::raw::c_void;
 use std::ffi::{CStr, CString};
 use std::slice;
 use std::ptr;
@@ -25,6 +26,17 @@ use url::Url;
 
 use utils::*;
 
+#[derive(Debug)]
+pub struct SourceController {
+    source: *mut c_void,
+}
+
+impl SourceController {
+    fn new(source: *mut c_void) -> SourceController {
+        SourceController { source: source }
+    }
+}
+
 pub trait Source: Sync + Send {
     // Called from any thread at any time
     fn set_uri(&mut self, uri: Option<Url>) -> bool;
@@ -41,6 +53,14 @@ pub trait Source: Sync + Send {
     fn get_size(&self) -> u64;
 }
 
+#[no_mangle]
+pub extern "C" fn source_new(source: *mut c_void,
+                             create_instance: extern "C" fn(controller: SourceController)
+                                                            -> *mut Box<Source>)
+                             -> *mut Box<Source> {
+    create_instance(SourceController::new(source))
+}
+
 #[no_mangle]
 pub extern "C" fn source_drop(ptr: *mut Box<Source>) {
     unsafe { Box::from_raw(ptr) };