utils: add DetachableTask & ContextGuard (#2138)

easytier/src/common/defer.rs

@@ -1,26 +0,0 @@
-#[doc(hidden)]
-pub struct Defer<F: FnOnce()> {
-    // internal struct used by defer! macro
-    func: Option<F>,
-}
-
-impl<F: FnOnce()> Defer<F> {
-    pub fn new(func: F) -> Self {
-        Self { func: Some(func) }
-    }
-}
-
-impl<F: FnOnce()> Drop for Defer<F> {
-    fn drop(&mut self) {
-        if let Some(f) = self.func.take() {
-            f()
-        }
-    }
-}
-
-#[macro_export]
-macro_rules! defer {
-	( $($tt:tt)* ) => {
-		let _deferred = $crate::common::defer::Defer::new(|| { $($tt)* });
-	};
-}

easytier/src/common/mod.rs

@@ -14,7 +14,6 @@ pub mod acl_processor;
 pub mod compressor;
 pub mod config;
 pub mod constants;
-pub mod defer;
 pub mod dns;
 pub mod env_parser;
 pub mod error;