Function FindBlockToFinalize

src/validation.cpp:2503–2549

}

static const CBlockIndex *FindBlockToFinalize(CBlockIndex *pindexNew)
// EXCLUSIVE_LOCKS_REQUIRED(cs_main)
{
    AssertLockHeld(cs_main);

    const int32_t minfinalizationdepth =
        gArgs.GetArg("-minfinalizationdepth", DEFAULT_MAX_REORG_DEPTH);

    const int64_t minfinalizationage =
        gArgs.GetArg("-minfinalizationage", DEFAULT_MIN_FINALIZATION_DELAY);

    // Find our candidate.
    // If minfinalizationdepth is < 0 pindex will be null and auto finalization
    // disabled
    const CBlockIndex *pindex =
        pindexNew->GetAncestor(pindexNew->nHeight - minfinalizationdepth);

    int64_t now = GetTime();

    // If the finalization delay is not expired since the startup time,
    // finalization should be avoided. Header receive time is not saved to disk
    // and so cannot be anterior to startup time.
    if (now < (GetStartupTime() + minfinalizationage)) {
        return nullptr;
    }

    // While our candidate is not eligible (finalization delay not expired), try
    // the previous one.
    while (pindex && (pindex != pindexFinalized)) {
        // Check that the block to finalize is known for a long enough time.
        // This test will ensure that an attacker could not cause a block to
        // finalize by forking the chain with a depth > minfinalizationdepth.
        // If the block is loaded from disk, header receive time is 0 and the
        // block will be finalized. This is safe because the delay since the
        // node startup is already expired.
        auto headerReceivedTime = pindex->GetHeaderReceivedTime();

        // If finalization delay is <= 0, finalization always occurs immediately
        if (now >= (headerReceivedTime + minfinalizationage)) {
            return pindex;
        }

        pindex = pindex->pprev;
    }

    return nullptr;
}

/**
 * Connect a new block to chainActive. pblock is either nullptr or a pointer to a CBlock