From 1c721cb20e44fdc7ec294792a9621d54361d344e Mon Sep 17 00:00:00 2001
From: kbleeke <pluth@0t.re>
Date: Mon, 27 Mar 2023 13:39:41 +0200
Subject: [PATCH] cancel ioctl when future is dropped

---
 src/control.rs | 23 ++++++++++++++++++++---
 src/ioctl.rs   |  4 ++++
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/src/control.rs b/src/control.rs
index 0dbf6d44..30d5d092 100644
--- a/src/control.rs
+++ b/src/control.rs
@@ -278,10 +278,27 @@ impl<'a> Control<'a> {
     }
 
     async fn ioctl(&mut self, kind: IoctlType, cmd: u32, iface: u32, buf: &mut [u8]) -> usize {
-        // TODO cancel ioctl on future drop.
+        struct CancelOnDrop<'a>(&'a IoctlState);
+
+        impl CancelOnDrop<'_> {
+            fn defuse(self) {
+                core::mem::forget(self);
+            }
+        }
+
+        impl Drop for CancelOnDrop<'_> {
+            fn drop(&mut self) {
+                self.0.cancel_ioctl();
+            }
+        }
+
+        let ioctl = CancelOnDrop(self.ioctl_state);
+
+        ioctl.0.do_ioctl(kind, cmd, iface, buf).await;
+        let resp_len = ioctl.0.wait_complete().await;
+
+        ioctl.defuse();
 
-        self.ioctl_state.do_ioctl(kind, cmd, iface, buf).await;
-        let resp_len = self.ioctl_state.wait_complete().await;
         resp_len
     }
 }
diff --git a/src/ioctl.rs b/src/ioctl.rs
index 6a746559..f5ab410d 100644
--- a/src/ioctl.rs
+++ b/src/ioctl.rs
@@ -88,6 +88,10 @@ impl IoctlState {
         pending
     }
 
+    pub fn cancel_ioctl(&self) {
+        self.state.set(IoctlStateInner::Done { resp_len: 0 });
+    }
+
     pub async fn do_ioctl(&self, kind: IoctlType, cmd: u32, iface: u32, buf: &mut [u8]) -> usize {
         warn!("doing ioctl");
         self.state