fix: query fresh state on timeout for Windows card events#116
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The previous timeout handler checked dwEventState from the timed-out SCardGetStatusChange call. On Windows, this value may just mirror dwCurrentState rather than reflecting actual hardware state, making the state divergence check ineffective. This fix explicitly queries fresh state using SCARD_STATE_UNAWARE when a timeout occurs, ensuring we detect card insert/remove events within ~1 second even when Windows PC/SC fails to set SCARD_STATE_CHANGED correctly.
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Summary
Fixes the remaining issue with Windows card events not firing reliably (#111).
Root cause: The timeout handler was checking
dwEventStatefrom the timed-outSCardGetStatusChangecall. On Windows, after a timeout,dwEventStatemay just mirrordwCurrentState(what was passed in) rather than reflecting the actual hardware state. This made the state divergence check ineffective.Fix: Explicitly query fresh state using
SCARD_STATE_UNAWAREwhen a timeout occurs. This ensures we get the real current hardware state and can detect missed card insert/remove events within ~1 second.Changes
reader_monitor.cppto query fresh state instead of relying on potentially staledwEventStateSCARD_STATE_UNAWAREwith zero timeout to force an immediate fresh state queryTest plan
Fixes #111