Bug: Type 2 warning realert window uses wrong config field (time_warning_fail_length instead of repeat_alert)

[somethingwithproof]

Summary

In thold_functions.php (line ~3289), the type 2 warning re-alert window is computed from the wrong field:

// Alert path (correct):
$realerttime = ($thold_data['repeat_alert'] - 1) * $step;

// Warning path (wrong field):
$realerttime = ($thold_data['time_warning_fail_length'] - 1) * $step;

The warning realert window uses time_warning_fail_length (the warning time window length) instead of repeat_alert (the configured re-alert interval). The $ra guard check also uses time_warning_fail_length as its truthy test.

Impact

Warning re-alerts fire at a completely wrong cadence, controlled by the wrong setting.

Fix

Implementation in #805.

[somethingwithproof]

Provenance: c7b889d8 (2016-04-30, "major rework of thold supporting multiple tholds per data source"). The alert path at the same site uses repeat_alert; the warning path has used time_warning_fail_length since that commit.

Blame run with -w -M -C.