Class CBlockIndex

src/chain.h:154–440

The block chain is a tree shaped structure starting with the * genesis block at the root, with each block potentially having multiple * candidates to be the next block. A blockindex may have multiple pprev pointing * to it, but at most one of them can be part of the currently active branch. */

 * to it, but at most one of them can be part of the currently active branch.
 */
class CBlockIndex
{
public:
    //! pointer to the hash of the block, if any. Memory is owned by this CBlockIndex
    const uint256* phashBlock{nullptr};

    //! pointer to the index of the predecessor of this block
    CBlockIndex* pprev{nullptr};

    //! pointer to the index of some further predecessor of this block
    CBlockIndex* pskip{nullptr};

    //! height of the entry in the chain. The genesis block has height 0
    int nHeight{0};

    //! Which # file this block is stored in (blk?????.dat)
    int nFile GUARDED_BY(::cs_main){0};

    //! Byte offset within blk?????.dat where this block's data is stored
    unsigned int nDataPos GUARDED_BY(::cs_main){0};

    //! Byte offset within rev?????.dat where this block's undo data is stored
    unsigned int nUndoPos GUARDED_BY(::cs_main){0};

    //! (memory only) Total amount of work (expected number of hashes) in the chain up to and including this block
    arith_uint256 nChainWork{};

    //! Number of transactions in this block.
    //! Note: in a potential headers-first mode, this number cannot be relied upon
    //! Note: this value is faked during UTXO snapshot load to ensure that
    //! LoadBlockIndex() will load index entries for blocks that we lack data for.
    //! @sa ActivateSnapshot
    unsigned int nTx{0};

    //! (memory only) Number of transactions in the chain up to and including this block.
    //! This value will be non-zero only if and only if transactions for this block and all its parents are available.
    //! Change to 64-bit type before 2024 (assuming worst case of 60 byte transactions).
    //!
    //! Note: this value is faked during use of a UTXO snapshot because we don't
    //! have the underlying block data available during snapshot load.
    //! @sa AssumeutxoData
    //! @sa ActivateSnapshot
    unsigned int nChainTx{0};

    //! Verification status of this block. See enum BlockStatus
    //!
    //! Note: this value is modified to show BLOCK_OPT_WITNESS during UTXO snapshot
    //! load to avoid the block index being spuriously rewound.
    //! @sa NeedsRedownload
    //! @sa ActivateSnapshot
    uint32_t nStatus GUARDED_BY(::cs_main){0};

    //! block header
    int32_t nVersion{0};
    uint256 hashMerkleRoot{};
    uint32_t nTime{0};
    uint32_t nBits{0};
    uint32_t nNonce{0};