Auto merge of #130 - faern:runloop-source-and-observer, r=jdm

Add runloop source and observer functionality

I had the need to add a source (from `SCDynamicStoreCreateRunLoopSource`). And since all the add/contains/remove operations were fairly trivial I did not see any reason to not complete them for timers, sources and observers at the same time.

Also adding the `CFRunLoopMode` type alias to make the signatures reflect the original API a bit more.

Lastly, removing underscore from `_info` since it's actually used.

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core-foundation/src/runloop.rs

@@ -18,6 +18,8 @@ use base::{TCFType};
 use date::{CFAbsoluteTime, CFTimeInterval};
 use string::{CFString};
 
+pub type CFRunLoopMode = CFStringRef;
+
 pub struct CFRunLoop(CFRunLoopRef);
 
 impl Drop for CFRunLoop {
@@ -70,18 +72,60 @@ impl CFRunLoop {
         }
     }
 
-    pub fn contains_timer(&self, timer: &CFRunLoopTimer, mode: CFStringRef) -> bool {
+    pub fn contains_timer(&self, timer: &CFRunLoopTimer, mode: CFRunLoopMode) -> bool {
         unsafe {
             CFRunLoopContainsTimer(self.0, timer.0, mode) != 0
         }
     }
 
-    pub fn add_timer(&self, timer: &CFRunLoopTimer, mode: CFStringRef) {
+    pub fn add_timer(&self, timer: &CFRunLoopTimer, mode: CFRunLoopMode) {
         unsafe {
             CFRunLoopAddTimer(self.0, timer.0, mode);
         }
     }
 
+    pub fn remove_timer(&self, timer: &CFRunLoopTimer, mode: CFRunLoopMode) {
+        unsafe {
+            CFRunLoopRemoveTimer(self.0, timer.0, mode);
+        }
+    }
+
+    pub fn contains_source(&self, source: &CFRunLoopSource, mode: CFRunLoopMode) -> bool {
+        unsafe {
+            CFRunLoopContainsSource(self.0, source.0, mode) != 0
+        }
+    }
+
+    pub fn add_source(&self, source: &CFRunLoopSource, mode: CFRunLoopMode) {
+        unsafe {
+            CFRunLoopAddSource(self.0, source.0, mode);
+        }
+    }
+
+    pub fn remove_source(&self, source: &CFRunLoopSource, mode: CFRunLoopMode) {
+        unsafe {
+            CFRunLoopRemoveSource(self.0, source.0, mode);
+        }
+    }
+
+    pub fn contains_observer(&self, observer: &CFRunLoopObserver, mode: CFRunLoopMode) -> bool {
+        unsafe {
+            CFRunLoopContainsObserver(self.0, observer.0, mode) != 0
+        }
+    }
+
+    pub fn add_observer(&self, observer: &CFRunLoopObserver, mode: CFRunLoopMode) {
+        unsafe {
+            CFRunLoopAddObserver(self.0, observer.0, mode);
+        }
+    }
+
+    pub fn remove_observer(&self, observer: &CFRunLoopObserver, mode: CFRunLoopMode) {
+        unsafe {
+            CFRunLoopRemoveObserver(self.0, observer.0, mode);
+        }
+    }
+
 }
 
 pub struct CFRunLoopTimer(CFRunLoopTimerRef);
@@ -105,6 +149,32 @@ impl CFRunLoopTimer {
     }
 }
 
+
+pub struct CFRunLoopSource(CFRunLoopSourceRef);
+
+impl Drop for CFRunLoopSource {
+    fn drop(&mut self) {
+        unsafe {
+            CFRelease(self.as_CFTypeRef())
+        }
+    }
+}
+
+impl_TCFType!(CFRunLoopSource, CFRunLoopSourceRef, CFRunLoopSourceGetTypeID);
+
+
+pub struct CFRunLoopObserver(CFRunLoopObserverRef);
+
+impl Drop for CFRunLoopObserver {
+    fn drop(&mut self) {
+        unsafe {
+            CFRelease(self.as_CFTypeRef())
+        }
+    }
+}
+
+impl_TCFType!(CFRunLoopObserver, CFRunLoopObserverRef, CFRunLoopObserverGetTypeID);
+
 #[cfg(test)]
 mod test {
     use super::*;
@@ -132,8 +202,8 @@ mod test {
         CFRunLoop::run_current();
     }
 
-    extern "C" fn timer_popped(_timer: CFRunLoopTimerRef, _info: *mut c_void) {
-        let previous_now_ptr: *const CFAbsoluteTime = unsafe { mem::transmute(_info) };
+    extern "C" fn timer_popped(_timer: CFRunLoopTimerRef, info: *mut c_void) {
+        let previous_now_ptr: *const CFAbsoluteTime = unsafe { mem::transmute(info) };
         let previous_now = unsafe { *previous_now_ptr };
         let now = CFDate::now().abs_time();
         assert!(now - previous_now > 0.19 && now - previous_now < 0.21);