versionbits: simplify state transitions

This removes the DEFINED->FAILED transition and changes the
STARTED->FAILED transition to only occur if signalling didn't pass the
threshold. This ensures that it is always possible for activation to
occur, no matter what settings are chosen, or the speed at which blocks
are found.
This commit is contained in:
Anthony Towns
2021-04-07 10:20:46 +10:00
parent 55ac5f568a
commit f054f6bcd2
3 changed files with 29 additions and 32 deletions

View File

@@ -147,19 +147,14 @@ FUZZ_TARGET_INIT(versionbits, initialize)
// pick the timestamp to switch based on a block
// note states will change *after* these blocks because mediantime lags
int start_block = fuzzed_data_provider.ConsumeIntegralInRange<int>(0, period * (max_periods - 3));
int end_block = fuzzed_data_provider.ConsumeIntegralInRange<int>(start_block, period * (max_periods - 3));
int end_block = fuzzed_data_provider.ConsumeIntegralInRange<int>(0, period * (max_periods - 3));
start_time = block_start_time + start_block * interval;
timeout = block_start_time + end_block * interval;
assert(start_time <= timeout);
// allow for times to not exactly match a block
if (fuzzed_data_provider.ConsumeBool()) start_time += interval / 2;
if (fuzzed_data_provider.ConsumeBool()) timeout += interval / 2;
// this may make timeout too early; if so, don't run the test
if (start_time > timeout) return;
} else {
if (fuzzed_data_provider.ConsumeBool()) {
start_time = Consensus::BIP9Deployment::ALWAYS_ACTIVE;
@@ -297,13 +292,12 @@ FUZZ_TARGET_INIT(versionbits, initialize)
assert(since == 0);
assert(exp_state == ThresholdState::DEFINED);
assert(current_block->GetMedianTimePast() < checker.m_begin);
assert(current_block->GetMedianTimePast() < checker.m_end);
break;
case ThresholdState::STARTED:
assert(current_block->GetMedianTimePast() >= checker.m_begin);
assert(current_block->GetMedianTimePast() < checker.m_end);
if (exp_state == ThresholdState::STARTED) {
assert(blocks_sig < threshold);
assert(current_block->GetMedianTimePast() < checker.m_end);
} else {
assert(exp_state == ThresholdState::DEFINED);
}
@@ -313,7 +307,6 @@ FUZZ_TARGET_INIT(versionbits, initialize)
assert(current_block->nHeight + 1 < min_activation);
} else {
assert(exp_state == ThresholdState::STARTED);
assert(current_block->GetMedianTimePast() < checker.m_end);
assert(blocks_sig >= threshold);
}
break;
@@ -323,7 +316,11 @@ FUZZ_TARGET_INIT(versionbits, initialize)
break;
case ThresholdState::FAILED:
assert(never_active_test || current_block->GetMedianTimePast() >= checker.m_end);
assert(exp_state != ThresholdState::LOCKED_IN && exp_state != ThresholdState::ACTIVE);
if (exp_state == ThresholdState::STARTED) {
assert(blocks_sig < threshold);
} else {
assert(exp_state == ThresholdState::FAILED);
}
break;
default:
assert(false);