ddnet #12467: EGL backend GL version negotiation

egl-version-negotiation.patch

diff --git a/src/engine/client/backend_egl.cpp b/src/engine/client/backend_egl.cpp
index 2d942a405..906487bc1 100644
--- a/src/engine/client/backend_egl.cpp
+++ b/src/engine/client/backend_egl.cpp
@@ -432,6 +432,7 @@ int CGraphicsBackend_EGL::InitOpenGL(int Width, int Height, int Flags, IStorage
 	}
 
 	int InitError = 0;
+	const char *pErrorStr = nullptr;
 	{
 		CCommandProcessorFragment_GLBase::SCommand_Init CmdGL;
 		CmdGL.m_pWindow = nullptr;
@@ -446,13 +447,13 @@ int CGraphicsBackend_EGL::InitOpenGL(int Width, int Height, int Flags, IStorage
 		CmdGL.m_pStorage = pStorage;
 		CmdGL.m_pCapabilities = &m_Capabilities;
 		CmdGL.m_pInitError = &InitError;
-		CmdGL.m_RequestedMajor = GlewMajor;
-		CmdGL.m_RequestedMinor = GlewMinor;
-		CmdGL.m_RequestedPatch = GlewPatch;
+		CmdGL.m_RequestedMajor = g_Config.m_GfxGLMajor;
+		CmdGL.m_RequestedMinor = g_Config.m_GfxGLMinor;
+		CmdGL.m_RequestedPatch = g_Config.m_GfxGLPatch;
 		CmdGL.m_GlewMajor = GlewMajor;
 		CmdGL.m_GlewMinor = GlewMinor;
 		CmdGL.m_GlewPatch = GlewPatch;
-		CmdGL.m_pErrStringPtr = nullptr;
+		CmdGL.m_pErrStringPtr = &pErrorStr;
 		CmdGL.m_pVendorString = m_aVendorString;
 		CmdGL.m_pVersionString = m_aVersionString;
 		CmdGL.m_pRendererString = m_aRendererString;
@@ -477,10 +478,43 @@ int CGraphicsBackend_EGL::InitOpenGL(int Width, int Height, int Flags, IStorage
 			WaitForIdle();
 			CmdBuffer.Reset();
 		}
+
+		CCommandProcessorFragment_EGL::SCommand_Shutdown CmdEGL;
+		CmdBuffer.AddCommandUnsafe(CmdEGL);
+		RunBuffer(&CmdBuffer);
+		WaitForIdle();
+		CmdBuffer.Reset();
+
+		CCommandProcessorFragment_GLBase::SCommand_PostShutdown CmdPost;
+		CmdBuffer.AddCommandUnsafe(CmdPost);
+		RunBufferSingleThreadedUnsafe(&CmdBuffer);
+		CmdBuffer.Reset();
+
 		StopProcessor();
 		delete m_pProcessor;
 		m_pProcessor = nullptr;
-		return -1;
+
+		eglDestroyContext(m_Display, m_Context);
+		eglDestroySurface(m_Display, m_Surface);
+		eglTerminate(m_Display);
+		m_Display = nullptr;
+		m_Context = nullptr;
+		m_Surface = nullptr;
+
+		// try setting to version string's supported version
+		if(InitError == -2)
+		{
+			g_Config.m_GfxGLMajor = m_Capabilities.m_ContextMajor;
+			g_Config.m_GfxGLMinor = m_Capabilities.m_ContextMinor;
+			g_Config.m_GfxGLPatch = m_Capabilities.m_ContextPatch;
+		}
+
+		if(pErrorStr != nullptr)
+		{
+			str_copy(m_aErrorString, pErrorStr);
+		}
+
+		return EGraphicsBackendErrorCodes::GRAPHICS_BACKEND_ERROR_CODE_GL_VERSION_FAILED;
 	}
 
 	// Viewport update