Fix PacLed64 null-deref on a controller with an unset Id - #59
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OnOutputValueChanged used std::map::operator[] on the lazily-populated units map, which inserts a null unit for a missing key and dereferences it; its three siblings (Init/Finish/Update) all guard with find(). A PacLed64 configured without an Id leaves m_id=-1 (Init map-populate skipped for -1), so the first output change null-derefs. C# throws KeyNotFoundException there. Guard with find() like the siblings.
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Hello. Thanks for the PR! Converting this to draft as per the contributing rules. (I was behind in getting them added as was just done in Visual Pinball). It's going to take time to review these. libdof is currently is use by several users with a variety of devices, and we have yet to receive issues about this. Also this definitely needs thorough testing with the actual hardware. |
jsm174
marked this pull request as draft
July 5, 2026 18:06
jsm174
marked this pull request as ready for review
July 6, 2026 19:08
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Fix
OnOutputValueChangedusedstd::map::operator[]on the lazily-populated units map — which inserts a null unit for a missing key and then dereferences it. Its three siblings (Init/Finish/Update) all guard withfind(). GuardOnOutputValueChangedthe same way.Why it matters
A PacLed64 configured without an
Idleavesm_id = -1;Init's map-populate is skipped for -1, so the first output change hitss_pacLed64Units[-1]→ insertsnullptr→ null-deref crash. C# pre-populates the dictionary in a static constructor and its indexer throwsKeyNotFoundExceptionthere instead of crashing.Found by diffing against the DirectOutput C# source.