1 files changed, 47 insertions(+), 1 deletions(-)

M src/main.rs

@@ 26,6 26,21 @@ without POSITION the current position will be printed to stdout\n",
     Ok(())
 }
 
+struct ScopeCall<F: FnMut()> {
+    c: F
+}
+impl<F: FnMut()> Drop for ScopeCall<F> {
+    fn drop(&mut self) {
+        (self.c)();
+    }
+}
+
+macro_rules! defer {
+    ($e:expr) => (
+        let _scope_call = ScopeCall { c: || -> () { $e; } };
+    )
+}
+
 fn main() -> Result<(), Box<dyn Error>> {
     let debug: bool = std::env::var("DEBUG").is_ok();
 


@@ 51,12 66,28 @@ fn main() -> Result<(), Box<dyn Error>> {
     if debug {
         eprintln!("adapter initialized");
     }
-    if !adapter.is_powered()? {
+    let powered = adapter.is_powered()?;
+    if !powered {
         if debug {
             eprintln!("adapter powering on");
         }
         adapter.set_powered(true)?;
+        if debug {
+            eprintln!("adapter powered on");
+        }
     }
+    defer!({
+        if debug {
+            eprintln!("adapter powering off");
+        }
+        if let Err(e) = adapter.set_powered(powered) {
+            eprintln!("adapter failed to power off: {}", e);
+            return;
+        }
+        if debug {
+            eprintln!("adapter powered off");
+        }
+    });
 
     let devices = adapter.get_device_list()?;
     if devices.is_empty() {


@@ 94,6 125,21 @@ fn main() -> Result<(), Box<dyn Error>> {
     if debug {
         eprintln!("connected");
     }
+    defer!({
+        if debug {
+            eprintln!(
+                "disconnecting from {}",
+                device.get_name().unwrap_or_else(|_| device.get_id())
+            );
+        }
+        if let Err(e) = device.disconnect() {
+            eprintln!("failed to disconnect: {}", e);
+            return;
+        }
+        if debug {
+            eprintln!("disconnected");
+        }
+    });
 
     let pos_svc = &get_service(session, device, POSITION_SERVICE_UUID)?;
     if debug {