Auto merge of #460 - xanathar:wip/mmp/runloop_ext, r=jrmuizel

Adds run_in_mode wrapper over CFRunLoopRunInMode

Adds a `run_in_mode` wrapper function which just makes `CFRunLoopRunInMode` a little more "rusty".

Also adds a `CFRunLoopRunResult` enum to type the return value.

core-foundation/src/runloop.rs

@@ -26,6 +26,14 @@ declare_TCFType!(CFRunLoop, CFRunLoopRef);
 impl_TCFType!(CFRunLoop, CFRunLoopRef, CFRunLoopGetTypeID);
 impl_CFTypeDescription!(CFRunLoop);
 
+#[derive(Copy, Clone, Debug, PartialEq)]
+pub enum CFRunLoopRunResult {
+    Finished = 1,
+    Stopped = 2,
+    TimedOut = 3,
+    HandledSource = 4,
+}
+
 impl CFRunLoop {
     pub fn get_current() -> CFRunLoop {
         unsafe {
@@ -47,6 +55,24 @@ impl CFRunLoop {
         }
     }
 
+    pub fn run_in_mode(
+        mode: CFStringRef,
+        duration: std::time::Duration,
+        return_after_source_handled: bool,
+    ) -> CFRunLoopRunResult {
+        let seconds = duration.as_secs_f64();
+        let return_after_source_handled = if return_after_source_handled { 1 } else { 0 };
+
+        unsafe {
+            match CFRunLoopRunInMode(mode, seconds, return_after_source_handled) {
+                2 => CFRunLoopRunResult::Stopped,
+                3 => CFRunLoopRunResult::TimedOut,
+                4 => CFRunLoopRunResult::HandledSource,
+                _ => CFRunLoopRunResult::Finished,
+            }
+        }
+    }
+
     pub fn stop(&self) {
         unsafe {
             CFRunLoopStop(self.0);