Function GuessVerificationProgress

src/validation.cpp:5131–5143

Guess how far we are in the verification process at the given block index. Since we have signed fixed-interval blocks, estimating progress is a very easy. We can extrapolate the last block time to the current time to estimate how many more blocks we expect.

//! We can extrapolate the last block time to the current time to estimate how many more blocks
//! we expect.
double GuessVerificationProgress(const CBlockIndex* pindex, int64_t blockInterval) {
    if (pindex == NULL || pindex->nHeight < 1) {
        return 0.0;
    }

    int64_t nNow = GetTime();
    int64_t moreBlocksExpected = (nNow - pindex->GetBlockTime()) / blockInterval;
    double progress = (pindex->nHeight + 0.0) / (pindex->nHeight + moreBlocksExpected);
    // Round to 3 digits to avoid 0.999999 when finished.
    progress = ceil(progress * 1000.0) / 1000.0;
    // Avoid higher than one if last block is newer than current time.
    return std::min(1.0, progress);
}

std::optional<uint256> ChainstateManager::SnapshotBlockhash() const
{