From db3fe694154c697afdaf3efb6ec65332546942e0 Mon Sep 17 00:00:00 2001
From: JohanGoversTech <35530199+JohanGoversTech@users.noreply.github.com>
Date: Thu, 14 Jun 2018 14:45:54 +0200
Subject: [PATCH] Change return type of add_probe to support removing (#116)

* Change return type of add_probe to support 0 PadProbeId

* use from_glib for the conversion of the PadProbeId
---
 gstreamer/src/pad.rs | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/gstreamer/src/pad.rs b/gstreamer/src/pad.rs
index c8869250a..0fefa8763 100644
--- a/gstreamer/src/pad.rs
+++ b/gstreamer/src/pad.rs
@@ -102,7 +102,7 @@ impl Drop for StreamLock {
 }
 
 pub trait PadExtManual {
-    fn add_probe<F>(&self, mask: PadProbeType, func: F) -> PadProbeId
+    fn add_probe<F>(&self, mask: PadProbeType, func: F) -> Option<PadProbeId>
     where
         F: Fn(&Pad, &mut PadProbeInfo) -> PadProbeReturn + Send + Sync + 'static;
     fn remove_probe(&self, id: PadProbeId);
@@ -225,7 +225,7 @@ pub trait PadExtManual {
 }
 
 impl<O: IsA<Pad>> PadExtManual for O {
-    fn add_probe<F>(&self, mask: PadProbeType, func: F) -> PadProbeId
+    fn add_probe<F>(&self, mask: PadProbeType, func: F) -> Option<PadProbeId>
     where
         F: Fn(&Pad, &mut PadProbeInfo) -> PadProbeReturn + Send + Sync + 'static,
     {
@@ -241,7 +241,11 @@ impl<O: IsA<Pad>> PadExtManual for O {
                 Some(destroy_closure),
             );
 
-            from_glib(id)
+            if id == 0 {
+                None
+            } else {
+                Some(from_glib(id))
+            }
         }
     }