GdiPlus Registering Race Condition

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   Hello,
when creating two different CXTPMarkupContexts both call in their constructor the function CXTPMarkupDrawingContext::Register(TRUE). As this leads to a registering of the CXTPSingleton CXTPGdiPlus 2x sometimes an assertion will be caused, when we got a bad timing.

Can anyone please help me solve this issue by fixing the race condition or telling me if I've used these classes in a wrong way and how to use them correctly?

Thanks for the help in advance.

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mgampi Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 14 July 2003 Status: Offline Points: 1201	Post Options Post Reply Quote mgampi Report Post Thanks(0) Quote Reply Topic: GdiPlus Registering Race Condition Posted: 03 September 2018 at 6:07am
	Hello, when creating two different CXTPMarkupContexts both call in their constructor the function CXTPMarkupDrawingContext::Register(TRUE). As this leads to a registering of the CXTPSingleton CXTPGdiPlus 2x sometimes an assertion will be caused, when we got a bad timing. Can anyone please help me solve this issue by fixing the race condition or telling me if I've used these classes in a wrong way and how to use them correctly? Thanks for the help in advance.
	Martin Product: Xtreme Toolkit v 22.1.0, new Projects v 24.0.0 Platform: Windows 10 v 22H2 (64bit) Language: VC++ 2022

agontarenko Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 25 March 2016 Status: Offline Points: 299	Post Options Post Reply Quote agontarenko Report Post Thanks(0) Quote Reply Posted: 05 September 2018 at 3:56am
	Hello Martin, how I can reproduce it with our samples? Regards, Artem Gontarenko

mgampi Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 14 July 2003 Status: Offline Points: 1201	Post Options Post Reply Quote mgampi Report Post Thanks(0) Quote Reply Posted: 05 September 2018 at 5:27am
	Hello, the easiest way would be to implement a sample that uses multithreading and do something like the following all the time until you get into the race condition: CSampleMarkupView* Wnd_ = new CSampleMarkupView(); //Calls CXTPMarkupDrawingContext::Register(TRUE) -> calls CXTPGdiPlus::Register(TRUE) // with ASSERT(m_nGdiplusToken == 0 && m_hModule == 0) (XTPGdiPlus.cpp Line 61) delete Wnd_; //Calls CXTPMarkupDrawingContext::Register(FALSE) -> calls CXTPGdiPlus::Register(FALSE) /* XTPGdiPlus.cpp Line 75ff: m_nCount--; if (m_nCount != 0) return; -----------------> if another thread that wants to call CXTPMarkupDrawingContext::Register(TRUE) interrupts our thread we got an assertion (ASSERT(m_nGdiplusToken == 0 && m_hModule == 0)) in XTPGdiPlus.cpp Line 61 if (m_hModule) { // Termination of background thread, which is causing the shutdown problem. gdiplusStartupOutput.NotificationUnhook(m_nGdiplusToken); GdiplusShutdown(m_nGdiplusToken); FreeLibrary(m_hModule); } m_hModule = NULL; m_nGdiplusToken = 0; */ using: class CSampleMarkupView : public CWnd, CXTPMarkupContext { public: CSampleMarkupView() : CWnd(), CXTPMarkupContext() {} virtual ~CSampleMarkupView() {} }; Best regards
	Martin Product: Xtreme Toolkit v 22.1.0, new Projects v 24.0.0 Platform: Windows 10 v 22H2 (64bit) Language: VC++ 2022

mgampi Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 14 July 2003 Status: Offline Points: 1201	Post Options Post Reply Quote mgampi Report Post Thanks(0) Quote Reply Posted: 05 September 2018 at 6:34am
	Fixed it. Thanks for the help! :)
	Martin Product: Xtreme Toolkit v 22.1.0, new Projects v 24.0.0 Platform: Windows 10 v 22H2 (64bit) Language: VC++ 2022

Marco1 Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 16 January 2004 Location: Germany Status: Offline Points: 251	Post Options Post Reply Quote Marco1 Report Post Thanks(0) Quote Reply Posted: 10 September 2018 at 1:21pm
	Was this problem related to your program?

mgampi Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 14 July 2003 Status: Offline Points: 1201	Post Options Post Reply Quote mgampi Report Post Thanks(0) Quote Reply Posted: 10 September 2018 at 1:23pm
	Yes! It's been my fault...
	Martin Product: Xtreme Toolkit v 22.1.0, new Projects v 24.0.0 Platform: Windows 10 v 22H2 (64bit) Language: VC++ 2022