From 65c0d507d3becb989cb7dc4cdefb3e25c265e5ad Mon Sep 17 00:00:00 2001
From: John Scipione <jscipione@gmail.com>
Date: Fri, 22 Feb 2019 23:52:43 -0800
Subject: [PATCH] MidiPlayer: Fix crash when dropping a midi file

Window must be locked or MidiRunThread crashes with a segment violation.

Change-Id: I9d5d0fa477475a9b5ba877aea3d6583690aacb2b
Reviewed-on: https://review.haiku-os.org/c/1080
Reviewed-by: Barrett17 <b.vitruvio@gmail.com>
---
 src/apps/midiplayer/MidiPlayerWindow.cpp | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/src/apps/midiplayer/MidiPlayerWindow.cpp b/src/apps/midiplayer/MidiPlayerWindow.cpp
index 84bdef07fb..908b28529f 100644
--- a/src/apps/midiplayer/MidiPlayerWindow.cpp
+++ b/src/apps/midiplayer/MidiPlayerWindow.cpp
@@ -427,17 +427,18 @@ MidiPlayerWindow::_StopHook(int32 arg)
 void
 MidiPlayerWindow::StopHook()
 {
-	Lock();
+	if (Lock()) {
 		// we may be called from the synth's thread
 
-	fIsPlaying = false;
+		fIsPlaying = false;
 
-	fScopeView->SetPlaying(false);
-	fScopeView->Invalidate();
-	fPlayButton->SetEnabled(true);
-	fPlayButton->SetLabel(B_TRANSLATE("Play"));
+		fScopeView->SetPlaying(false);
+		fScopeView->Invalidate();
+		fPlayButton->SetEnabled(true);
+		fPlayButton->SetLabel(B_TRANSLATE("Play"));
 
-	Unlock();
+		Unlock();
+	}
 }