Dropping the Sink now stops all sounds

src/engine.rs

@@ -100,7 +100,7 @@ impl Engine {
         // the iterator that produces sounds
         let next_sounds = Arc::new(Mutex::new(Vec::new()));
         let source = QueueIterator { current: Box::new(None.into_iter()), next: next_sounds.clone() };
-        let source_id = &next_sounds as *const _ as *const u8 as usize;
+        let source_id = &*next_sounds as *const Mutex<_> as *const u8 as usize;
 
         // at each loop, the background thread will store the remaining time of the sound in this
         // value
@@ -165,8 +165,10 @@ impl<'a> Handle<'a> {
         commands.send(Command::SetVolume(self.source_id, value)).unwrap();
     }
 
+    // note that this method could take `self` instead of `&self`, but it makes `Sink`'s life
+    // easier not to take `self`
     #[inline]
-    pub fn stop(self) {
+    pub fn stop(&self) {
         let commands = self.engine.commands.lock().unwrap();
         commands.send(Command::Stop(self.source_id)).unwrap();
 
@@ -222,7 +224,7 @@ fn background(rx: Receiver<Command>) {
                 Command::Stop(decoder) => {
                     for (_, &mut (_, ref mut sounds)) in voices.iter_mut() {
                         sounds.retain(|dec| {
-                            &*dec.0.next as *const _ as *const u8 as usize != decoder
+                            &*dec.0.next as *const Mutex<_> as *const u8 as usize != decoder
                         })
                     }
                 },
@@ -230,7 +232,7 @@ fn background(rx: Receiver<Command>) {
                 Command::SetVolume(decoder, volume) => {
                     for (_, &mut (_, ref mut sounds)) in voices.iter_mut() {
                         if let Some(d) = sounds.iter_mut()
-                                               .find(|dec| &*dec.0.next as *const _ as *const u8 as usize == decoder)
+                                               .find(|dec| &*dec.0.next as *const Mutex<_> as *const u8 as usize == decoder)
                         {
                             d.2 = volume;
                         }
@@ -242,7 +244,7 @@ fn background(rx: Receiver<Command>) {
         // removing sounds that have finished playing
         for decoder in mem::replace(&mut sounds_to_remove, Vec::new()) {
             for (_, &mut (_, ref mut sounds)) in voices.iter_mut() {
-                sounds.retain(|dec| &*dec.0.next as *const _ != decoder);
+                sounds.retain(|dec| &*dec.0.next as *const Mutex<_> != decoder);
             }
         }
 

src/lib.rs

@@ -28,20 +28,30 @@ lazy_static! {
     static ref ENGINE: engine::Engine = engine::Engine::new();
 }
 
-/// Handle to a playing sound.
+/// Handle to an endpoint that outputs sounds.
 ///
-/// Note that dropping the handle doesn't stop the sound. You must call `stop` explicitely.
-pub struct Sink(engine::Handle<'static>);
+/// Dropping the `Sink` stops all sounds. You can use `detach` if you want the sounds to continue
+/// playing.
+pub struct Sink {
+    handle: engine::Handle<'static>,
+    // if true, then the sound will stop playing at the end
+    stop: bool,
+}
 
 impl Sink {
+    /// Builds a new `Sink`.
     pub fn new(endpoint: &Endpoint) -> Sink {
-        Sink(ENGINE.start(&endpoint))
+        Sink {
+            handle: ENGINE.start(&endpoint),
+            stop: true,
+        }
     }
 
+    /// Appends a sound to the queue of sounds to play.
     pub fn append<S>(&self, source: S) where S: Source + Send + 'static,
                                              S::Item: Sample, S::Item: Send
     {
-        self.0.append(source);
+        self.handle.append(source);
     }
 
     /// Changes the volume of the sound.
@@ -50,13 +60,13 @@ impl Sink {
     /// multiply each sample by this value.
     #[inline]
     pub fn set_volume(&mut self, value: f32) {
-        self.0.set_volume(value);
+        self.handle.set_volume(value);
     }
 
-    /// Stops the sound.
+    /// Destroys the sink without stopping the sounds that are still playing.
     #[inline]
-    pub fn stop(self) {
-        self.0.stop()
+    pub fn detach(mut self) {
+        self.stop = false;
     }
 
     /// Returns the minimum duration before the end of the sounds submitted to this sink.
@@ -64,7 +74,7 @@ impl Sink {
     /// Note that this is a minimum value, and the sound can last longer.
     #[inline]
     pub fn get_min_remaining_duration(&self) -> Duration {
-        self.0.get_min_remaining_duration()
+        self.handle.get_min_remaining_duration()
     }
 
     /// Sleeps the current thread until the sound ends.
@@ -75,6 +85,15 @@ impl Sink {
     }
 }
 
+impl Drop for Sink {
+    #[inline]
+    fn drop(&mut self) {
+        if self.stop {
+            self.handle.stop();
+        }
+    }
+}
+
 /// Plays a sound once. Returns a `Sink` that can be used to control the sound.
 #[inline]
 pub fn play_once<R>(endpoint: &Endpoint, input: R) -> Sink