From 8cbff50461adf03aae367fe314c22279b77f51b8 Mon Sep 17 00:00:00 2001
From: Jupeyy <jupjopjap@gmail.com>
Date: Tue, 15 Feb 2022 16:27:53 +0100
Subject: [PATCH] Give the condition waits proper conditions

---
 src/engine/client/backend_sdl.cpp | 12 +++++++-----
 src/engine/client/backend_sdl.h   |  1 +
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/src/engine/client/backend_sdl.cpp b/src/engine/client/backend_sdl.cpp
index 150cb77aa..3beb205da 100644
--- a/src/engine/client/backend_sdl.cpp
+++ b/src/engine/client/backend_sdl.cpp
@@ -61,6 +61,7 @@ void CGraphicsBackend_Threaded::ThreadFunc(void *pUser)
 	auto *pSelf = (CGraphicsBackend_Threaded *)pUser;
 	std::unique_lock<std::mutex> Lock(pSelf->m_BufferSwapMutex);
 	// notify, that the thread started
+	pSelf->m_Started = true;
 	pSelf->m_BufferDoneCond.notify_all();
 	while(!pSelf->m_Shutdown)
 	{
@@ -75,11 +76,12 @@ void CGraphicsBackend_Threaded::ThreadFunc(void *pUser)
 			pSelf->m_pBuffer = nullptr;
 			pSelf->m_BufferInProcess.store(false, std::memory_order_relaxed);
 			pSelf->m_BufferDoneCond.notify_all();
-		}
+
 #if defined(CONF_VIDEORECORDER)
-		if(IVideo::Current())
-			IVideo::Current()->NextVideoFrameThread();
+			if(IVideo::Current())
+				IVideo::Current()->NextVideoFrameThread();
 #endif
+		}
 	}
 }
 
@@ -97,7 +99,7 @@ void CGraphicsBackend_Threaded::StartProcessor(ICommandProcessor *pProcessor)
 	std::unique_lock<std::mutex> Lock(m_BufferSwapMutex);
 	m_Thread = thread_init(ThreadFunc, this, "Graphics thread");
 	// wait for the thread to start
-	m_BufferDoneCond.wait(Lock);
+	m_BufferDoneCond.wait(Lock, [this]() -> bool { return m_Started; });
 }
 
 void CGraphicsBackend_Threaded::StopProcessor()
@@ -127,7 +129,7 @@ bool CGraphicsBackend_Threaded::IsIdle() const
 void CGraphicsBackend_Threaded::WaitForIdle()
 {
 	std::unique_lock<std::mutex> Lock(m_BufferSwapMutex);
-	if(m_pBuffer != nullptr)
+	while(m_pBuffer != nullptr)
 		m_BufferDoneCond.wait(Lock);
 }
 
diff --git a/src/engine/client/backend_sdl.h b/src/engine/client/backend_sdl.h
index 77d1c59c6..e2f8a8ab7 100644
--- a/src/engine/client/backend_sdl.h
+++ b/src/engine/client/backend_sdl.h
@@ -72,6 +72,7 @@ private:
 	std::condition_variable m_BufferDoneCond;
 	CCommandBuffer *m_pBuffer;
 	std::atomic_bool m_Shutdown;
+	bool m_Started = false;
 	std::atomic_bool m_BufferInProcess;
 	void *m_Thread;