void qga_vss_fsfreeze(int *nr_volume, Error **errp, bool freeze) { const char *func_name = freeze ? "requester_freeze" : "requester_thaw"; QGAVSSRequesterFunc func; ErrorSet errset = { .error_setg_win32 = error_setg_win32, .errp = errp, }; g_assert(errp); /* requester.cpp requires it */ func = (QGAVSSRequesterFunc)GetProcAddress(provider_lib, func_name); if (!func) { error_setg_win32(errp, GetLastError(), "failed to load %s from %s", func_name, QGA_VSS_DLL); return; } func(nr_volume, &errset); }