Do not panic when join handle is canceled

Author: dlon

tunnel-obfuscation/src/shadowsocks.rs

@@ -227,10 +227,11 @@ impl Obfuscator for Shadowsocks {
     }
 
     async fn run(self: Box<Self>) -> crate::Result<()> {
-        self.server
-            .await
-            .expect("server handle panicked")
-            .map_err(crate::Error::RunShadowsocksObfuscator)
+        match self.server.await {
+            Ok(result) => result.map_err(crate::Error::RunShadowsocksObfuscator),
+            Err(_err) if _err.is_cancelled() => Ok(()),
+            Err(_err) => panic!("server handle panicked"),
+        }
     }
 
     #[cfg(target_os = "android")]