From 4ccaf57d9d2ca3c603ce967cc8c288844f928912 Mon Sep 17 00:00:00 2001
From: Dan Muller <dan.muller@dmuller.us>
Date: Sun, 16 Oct 2022 15:45:26 -0400
Subject: [PATCH] drop() no longer calls midiOutReset Fixes #122

On Windows, midiOutReset was being called before midiOutClose,
presumably to cancel any pending output. This caused extra MIDI
commands to be sent. Instead, we now call midiOutClose repeatedly
until it's no longer blocked by pending output.
---
 src/backend/winmm/mod.rs | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/src/backend/winmm/mod.rs b/src/backend/winmm/mod.rs
index 3ec59a6..4f8e599 100644
--- a/src/backend/winmm/mod.rs
+++ b/src/backend/winmm/mod.rs
@@ -21,7 +21,7 @@ use windows::Win32::Media::Audio::{
     midiInOpen, midiInPrepareHeader, midiInReset, midiInStart,
     midiInStop, midiInUnprepareHeader, midiOutClose,
     midiOutGetDevCapsW, midiOutGetNumDevs, midiOutLongMsg, midiOutOpen,
-    midiOutPrepareHeader, midiOutReset, midiOutShortMsg,
+    midiOutPrepareHeader, midiOutShortMsg,
     midiOutUnprepareHeader, midiInMessage, midiOutMessage,
     HMIDIIN, HMIDIOUT, MIDIHDR, MIDIINCAPSW, MIDIOUTCAPSW, CALLBACK_FUNCTION, CALLBACK_NULL,
     MIDIERR_NOTREADY, MIDIERR_STILLPLAYING,
@@ -533,9 +533,12 @@ impl MidiOutputConnection {
 
 impl Drop for MidiOutputConnection {
     fn drop(&mut self) {
-        unsafe {
-            midiOutReset(self.out_handle);
-            midiOutClose(self.out_handle);
+        loop {
+            let result = unsafe { midiOutClose(self.out_handle) };
+            if result == MIDIERR_STILLPLAYING {
+                sleep(Duration::from_millis(1));
+                continue;
+            } else { break; }
         }
     }
 }