Fix unsigned underflow in Voter voting-delay timer computation - #806
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MarkRose wants to merge 1 commit into
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Fix unsigned underflow in Voter voting-delay timer computation#806MarkRose wants to merge 1 commit into
MarkRose wants to merge 1 commit into
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- In Voter::VotingDelay::init(), the voting delay timer was computed as max(votingDelay() - srx->sqlOpenDelay(), 0U). Since both operands are unsigned, a receiver whose sql-open-delay exceeds the voting delay causes the subtraction to wrap around to a huge unsigned value (~4.29e9) before max() ever gets a chance to clamp it. The timer is then armed for roughly 49 days instead of firing immediately, stalling squelch-open selection for that receiver. Fixed by computing the difference with signed arithmetic and clamping the result to a minimum of zero before it is passed to the unsigned-taking startTimer().
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max(votingDelay() - srx->sqlOpenDelay(), 0U). Since both operands are
unsigned, a receiver whose sql-open-delay exceeds the voting delay
causes the subtraction to wrap around to a huge unsigned value
(~4.29e9) before max() ever gets a chance to clamp it. The timer is
then armed for roughly 49 days instead of firing immediately,
stalling squelch-open selection for that receiver. Fixed by computing
the difference with signed arithmetic and clamping the result to a
minimum of zero before it is passed to the unsigned-taking
startTimer().
This PR also adds a unit test (
VoterTest.cpp). It is auto-discovered and executed by the CTest suite proposed in #762 once that is merged; without that suite present the test file is inert and does not affect the build.