Replace the bare-TCP-only AbCipDriverProbe with a two-phase check:
Phase 1 keeps the existing TCP preflight; Phase 2 initialises a
LibplctagTagRuntime against the first device to open a real EIP session
and CIP Forward Open, so a live-but-rejecting CIP endpoint reads red
instead of a false-positive green.
Status mapping: ErrorNotFound / ErrorNoMatch / ErrorBadDevice → reachable
(controller answered CIP, probe tag absent); ErrorTimeout / ErrorBadConnection
/ ErrorBadGateway / ErrorWinsock / ErrorOpen / ErrorClose / ErrorRead /
ErrorWrite / ErrorBadReply / ErrorRemoteErr / ErrorPartial / ErrorAbort →
handshake failed. LibPlcTagException message text is used as a secondary
signal for the reachable-exception path. All other statuses default to
handshake-failed (conservative).
Add AbCipDriverProbeTests: invalid JSON, no devices, malformed host address,
closed-port TCP rejection, and black-hole timeout — all offline-determinable.
Happy path + CIP-error path covered live against the CIP sim.
Joseph Doherty
0c08b152c2