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Fix silent startup deadlock on Windows 11 due to premature FreeLibrary #1155

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Merged
sabrogden merged 2 commits into from
Sep 22, 2026
Merged

Fix silent startup deadlock on Windows 11 due to premature FreeLibrary #1155

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e6c745c
Fix silent startup deadlock on Windows 11 due to premature FreeLibrary
int03 Sep 22, 2026
49d5254
Address review feedback: only unload powrprof if unregister succeeds
int03 Sep 22, 2026
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43 changes: 27 additions & 16 deletions src/PowerManager.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -30,49 +30,60 @@ ULONG PowerChanged(PVOID Context, ULONG Type, PVOID Setting)
CPowerManager::CPowerManager()
{
m_registrationHandle = 0;
m_hPowrProf = NULL;
}


CPowerManager::~CPowerManager(void)
{
Close();
}


void CPowerManager::Start(HWND hWnd)
{
s_notifyHwnd = hWnd;

HMODULE powrprof = LoadLibrary( _T("powrprof.dll") );
if( powrprof != NULL )
if (m_hPowrProf == NULL)
{
DWORD (_stdcall*PowerRegisterSuspendResumeNotification)(_In_ DWORD,_In_ HANDLE,_Out_ PHPOWERNOTIFY);
PowerRegisterSuspendResumeNotification = (DWORD(_stdcall*)(_In_ DWORD,_In_ HANDLE,_Out_ PHPOWERNOTIFY))GetProcAddress(powrprof, "PowerRegisterSuspendResumeNotification");
if(PowerRegisterSuspendResumeNotification)
m_hPowrProf = LoadLibrary(_T("powrprof.dll"));
}

if (m_hPowrProf != NULL && m_registrationHandle == 0)
{
DWORD (_stdcall*PowerRegisterSuspendResumeNotification)(_In_ DWORD, _In_ HANDLE, _Out_ PHPOWERNOTIFY);
PowerRegisterSuspendResumeNotification = (DWORD(_stdcall*)(_In_ DWORD, _In_ HANDLE, _Out_ PHPOWERNOTIFY))GetProcAddress(m_hPowrProf, "PowerRegisterSuspendResumeNotification");
if (PowerRegisterSuspendResumeNotification)
{
static _DEVICE_NOTIFY_SUBSCRIBE_PARAMETERS testCallback = {PowerChanged, nullptr};

PowerRegisterSuspendResumeNotification(DEVICE_NOTIFY_CALLBACK, &testCallback, &m_registrationHandle);
}

::FreeLibrary(powrprof);
}
}

void CPowerManager::Close()
{
if(m_registrationHandle != 0)
if (m_hPowrProf != NULL)
{
HMODULE powrprof = LoadLibrary( _T("powrprof.dll") );
if( powrprof != NULL )
if (m_registrationHandle != 0)
{
DWORD (_stdcall*PowerUnregisterSuspendResumeNotification)(_Inout_ PHPOWERNOTIFY);
PowerUnregisterSuspendResumeNotification = (DWORD(_stdcall*)(_Inout_ PHPOWERNOTIFY))GetProcAddress(powrprof, "PowerUnregisterSuspendResumeNotification");
if(PowerUnregisterSuspendResumeNotification)
DWORD (_stdcall*PowerUnregisterSuspendResumeNotification)(_Inout_ HPOWERNOTIFY);
PowerUnregisterSuspendResumeNotification = (DWORD(_stdcall*)(_Inout_ HPOWERNOTIFY))GetProcAddress(m_hPowrProf, "PowerUnregisterSuspendResumeNotification");
if (PowerUnregisterSuspendResumeNotification)
{
PowerUnregisterSuspendResumeNotification(&m_registrationHandle);
DWORD ret = PowerUnregisterSuspendResumeNotification(m_registrationHandle);
if (ret == ERROR_SUCCESS)
{
m_registrationHandle = 0;
}
}
}

::FreeLibrary(powrprof);
if (m_registrationHandle == 0)
{
::FreeLibrary(m_hPowrProf);
m_hPowrProf = NULL;
}
}
}
}
3 changes: 2 additions & 1 deletion src/PowerManager.h
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Original file line number Diff line number Diff line change
Expand Up @@ -26,9 +26,10 @@ class CPowerManager
~CPowerManager(void);

void Start(HWND hWnd);
void CPowerManager::Close();
void Close();

protected:
HPOWERNOTIFY m_registrationHandle;
HMODULE m_hPowrProf;
};