refactor(multipart): move Safety to module

actix-multipart/src/lib.rs

@@ -60,6 +60,7 @@ extern crate self as actix_multipart;
 mod error;
 mod extractor;
 pub mod form;
+pub(crate) mod safety;
 mod server;
 pub mod test;
 

actix-multipart/src/safety.rs

@@ -0,0 +1,60 @@
+use std::{cell::Cell, marker::PhantomData, rc::Rc, task};
+
+use local_waker::LocalWaker;
+
+/// Counter. It tracks of number of clones of payloads and give access to payload only to top most.
+///
+/// - When dropped, parent task is awakened. This is to support the case where `Field` is dropped in
+///   a separate task than `Multipart`.
+/// - Assumes that parent owners don't move to different tasks; only the top-most is allowed to.
+/// - If dropped and is not top most owner, is_clean flag is set to false.
+#[derive(Debug)]
+pub(crate) struct Safety {
+    task: LocalWaker,
+    level: usize,
+    payload: Rc<PhantomData<bool>>,
+    clean: Rc<Cell<bool>>,
+}
+
+impl Safety {
+    pub(crate) fn new() -> Safety {
+        let payload = Rc::new(PhantomData);
+        Safety {
+            task: LocalWaker::new(),
+            level: Rc::strong_count(&payload),
+            clean: Rc::new(Cell::new(true)),
+            payload,
+        }
+    }
+
+    pub(crate) fn current(&self) -> bool {
+        Rc::strong_count(&self.payload) == self.level && self.clean.get()
+    }
+
+    pub(crate) fn is_clean(&self) -> bool {
+        self.clean.get()
+    }
+
+    pub(crate) fn clone(&self, cx: &task::Context<'_>) -> Safety {
+        let payload = Rc::clone(&self.payload);
+        let s = Safety {
+            task: LocalWaker::new(),
+            level: Rc::strong_count(&payload),
+            clean: self.clean.clone(),
+            payload,
+        };
+        s.task.register(cx.waker());
+        s
+    }
+}
+
+impl Drop for Safety {
+    fn drop(&mut self) {
+        if Rc::strong_count(&self.payload) != self.level {
+            // Multipart dropped leaving a Field
+            self.clean.set(false);
+        }
+
+        self.task.wake();
+    }
+}

actix-multipart/src/server.rs

@@ -1,9 +1,8 @@
 //! Multipart response payload support.
 
 use std::{
-    cell::{Cell, RefCell, RefMut},
+    cell::{RefCell, RefMut},
     cmp, fmt,
-    marker::PhantomData,
     pin::Pin,
     rc::Rc,
     task::{Context, Poll},
@@ -17,10 +16,9 @@ use actix_web::{
 };
 use bytes::{Bytes, BytesMut};
 use futures_core::stream::{LocalBoxStream, Stream};
-use local_waker::LocalWaker;
 use mime::Mime;
 
-use crate::error::MultipartError;
+use crate::{error::MultipartError, safety::Safety};
 
 const MAX_HEADERS: usize = 32;
 
@@ -797,63 +795,6 @@ impl Clone for PayloadRef {
     }
 }
 
-/// Counter. It tracks of number of clones of payloads and give access to payload only to top most.
-///
-/// - When dropped, parent task is awakened. This is to support the case where `Field` is dropped in
-///   a separate task than `Multipart`.
-/// - Assumes that parent owners don't move to different tasks; only the top-most is allowed to.
-/// - If dropped and is not top most owner, is_clean flag is set to false.
-#[derive(Debug)]
-struct Safety {
-    task: LocalWaker,
-    level: usize,
-    payload: Rc<PhantomData<bool>>,
-    clean: Rc<Cell<bool>>,
-}
-
-impl Safety {
-    fn new() -> Safety {
-        let payload = Rc::new(PhantomData);
-        Safety {
-            task: LocalWaker::new(),
-            level: Rc::strong_count(&payload),
-            clean: Rc::new(Cell::new(true)),
-            payload,
-        }
-    }
-
-    fn current(&self) -> bool {
-        Rc::strong_count(&self.payload) == self.level && self.clean.get()
-    }
-
-    fn is_clean(&self) -> bool {
-        self.clean.get()
-    }
-
-    fn clone(&self, cx: &Context<'_>) -> Safety {
-        let payload = Rc::clone(&self.payload);
-        let s = Safety {
-            task: LocalWaker::new(),
-            level: Rc::strong_count(&payload),
-            clean: self.clean.clone(),
-            payload,
-        };
-        s.task.register(cx.waker());
-        s
-    }
-}
-
-impl Drop for Safety {
-    fn drop(&mut self) {
-        if Rc::strong_count(&self.payload) != self.level {
-            // Multipart dropped leaving a Field
-            self.clean.set(false);
-        }
-
-        self.task.wake();
-    }
-}
-
 /// Payload buffer.
 struct PayloadBuffer {
     eof: bool,