From 9abaeaf8d8ec814f5a13de95e51c3efd7a026e4d Mon Sep 17 00:00:00 2001
From: Sour <mesenemu@gmail.com>
Date: Thu, 28 Dec 2017 16:30:37 -0500
Subject: [PATCH] Debugger: Fixed infrequent deadlock when switching games
 while debugger window is opened

---
 Core/Console.cpp | 11 +++++++++--
 Core/Console.h   |  1 +
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/Core/Console.cpp b/Core/Console.cpp
index b7a2af79..d735a586 100644
--- a/Core/Console.cpp
+++ b/Core/Console.cpp
@@ -163,6 +163,8 @@ bool Console::Initialize(VirtualFile &romFile, VirtualFile &patchFile)
 			_initialized = true;
 
 			if(_debugger) {
+				//Reset debugger if it was running before
+				auto lock = _debuggerLock.AcquireSafe();
 				StopDebugger();
 				GetDebugger();
 			}
@@ -660,8 +662,13 @@ std::shared_ptr<Debugger> Console::GetDebugger(bool autoStart)
 {
 	shared_ptr<Debugger> debugger = _debugger;
 	if(!debugger && autoStart) {
-		debugger.reset(new Debugger(Console::Instance, _cpu, _ppu, _apu, _memoryManager, _mapper));
-		_debugger = debugger;
+		//Lock to make sure we don't try to start debuggers in 2 separate threads at once
+		auto lock = _debuggerLock.AcquireSafe();
+		debugger = _debugger;
+		if(!debugger) {
+			debugger.reset(new Debugger(Console::Instance, _cpu, _ppu, _apu, _memoryManager, _mapper));
+			_debugger = debugger;
+		}
 	}
 	return debugger;
 }
diff --git a/Core/Console.h b/Core/Console.h
index 2742ea2e..82dbb035 100644
--- a/Core/Console.h
+++ b/Core/Console.h
@@ -31,6 +31,7 @@ class Console
 		SimpleLock _pauseLock;
 		SimpleLock _runLock;
 		SimpleLock _stopLock;
+		SimpleLock _debuggerLock;
 
 		shared_ptr<RewindManager> _rewindManager;
 		shared_ptr<CPU> _cpu;