Method BatchWrite

src/coins.cpp:189–258

}

void CCoinsViewCache::BatchWrite(CoinsViewCacheCursor& cursor, const uint256& in_block_hash)
{
    for (auto it{cursor.Begin()}; it != cursor.End(); it = cursor.NextAndMaybeErase(*it)) {
        if (!it->second.IsDirty()) { // TODO a cursor can only contain dirty entries
            continue;
        }
        auto [itUs, inserted]{cacheCoins.try_emplace(it->first)};
        if (inserted) {
            if (it->second.IsFresh() && it->second.coin.IsSpent()) {
                cacheCoins.erase(itUs); // TODO fresh coins should have been removed at spend
            } else {
                // The parent cache does not have an entry, while the child cache does.
                // Move the data up and mark it as dirty.
                CCoinsCacheEntry& entry{itUs->second};
                assert(entry.coin.DynamicMemoryUsage() == 0);
                if (cursor.WillErase(*it)) {
                    // Since this entry will be erased,
                    // we can move the coin into us instead of copying it
                    entry.coin = std::move(it->second.coin);
                } else {
                    entry.coin = it->second.coin;
                }
                CCoinsCacheEntry::SetDirty(*itUs, m_sentinel);
                ++m_dirty_count;
                cachedCoinsUsage += entry.coin.DynamicMemoryUsage();
                // We can mark it FRESH in the parent if it was FRESH in the child
                // Otherwise it might have just been flushed from the parent's cache
                // and already exist in the grandparent
                if (it->second.IsFresh()) CCoinsCacheEntry::SetFresh(*itUs, m_sentinel);
            }
        } else {
            // Found the entry in the parent cache
            if (it->second.IsFresh() && !itUs->second.coin.IsSpent()) {
                // The coin was marked FRESH in the child cache, but the coin
                // exists in the parent cache. If this ever happens, it means
                // the FRESH flag was misapplied and there is a logic error in
                // the calling code.
                throw std::logic_error("FRESH flag misapplied to coin that exists in parent cache");
            }

            if (itUs->second.IsFresh() && it->second.coin.IsSpent()) {
                // The grandparent cache does not have an entry, and the coin
                // has been spent. We can just delete it from the parent cache.
                Assume(TrySub(m_dirty_count, itUs->second.IsDirty()));
                Assume(TrySub(cachedCoinsUsage, itUs->second.coin.DynamicMemoryUsage()));
                cacheCoins.erase(itUs);
            } else {
                // A normal modification.
                Assume(TrySub(cachedCoinsUsage, itUs->second.coin.DynamicMemoryUsage()));
                if (cursor.WillErase(*it)) {
                    // Since this entry will be erased,
                    // we can move the coin into us instead of copying it
                    itUs->second.coin = std::move(it->second.coin);
                } else {
                    itUs->second.coin = it->second.coin;
                }
                cachedCoinsUsage += itUs->second.coin.DynamicMemoryUsage();
                if (!itUs->second.IsDirty()) {