Method Sync

src/index/base.cpp:207–274

}

void BaseIndex::Sync()
{
    const CBlockIndex* pindex = m_best_block_index.load();
    if (!m_synced) {
        auto last_log_time{NodeClock::now()};
        auto last_locator_write_time{last_log_time};
        while (true) {
            if (m_interrupt) {
                LogInfo("%s: m_interrupt set; exiting ThreadSync", GetName());

                SetBestBlockIndex(pindex);
                // No need to handle errors in Commit. If it fails, the error will be already be
                // logged. The best way to recover is to continue, as index cannot be corrupted by
                // a missed commit to disk for an advanced index state.
                Commit();
                return;
            }

            const CBlockIndex* pindex_next = WITH_LOCK(cs_main, return NextSyncBlock(pindex, m_chainstate->m_chain));
            // If pindex_next is null, it means pindex is the chain tip, so
            // commit data indexed so far.
            if (!pindex_next) {
                SetBestBlockIndex(pindex);
                // No need to handle errors in Commit. See rationale above.
                Commit();

                // If pindex is still the chain tip after committing, exit the
                // sync loop. It is important for cs_main to be locked while
                // setting m_synced = true, otherwise a new block could be
                // attached while m_synced is still false, and it would not be
                // indexed.
                LOCK(::cs_main);
                pindex_next = NextSyncBlock(pindex, m_chainstate->m_chain);
                if (!pindex_next) {
                    m_synced = true;
                    break;
                }
            }
            if (pindex_next->pprev != pindex && !Rewind(pindex, pindex_next->pprev)) {
                FatalErrorf("Failed to rewind %s to a previous chain tip", GetName());
                return;
            }
            pindex = pindex_next;


            if (!ProcessBlock(pindex)) return; // error logged internally

            auto current_time{NodeClock::now()};
            if (current_time - last_log_time >= SYNC_LOG_INTERVAL) {
                LogInfo("Syncing %s with block chain from height %d", GetName(), pindex->nHeight);
                last_log_time = current_time;
            }

            if (current_time - last_locator_write_time >= SYNC_LOCATOR_WRITE_INTERVAL) {
                SetBestBlockIndex(pindex);
                last_locator_write_time = current_time;
                // No need to handle errors in Commit. See rationale above.
                Commit();