text: // Copyright (c) 2014-2018, The Monero Project
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without modification, are
  // permitted provided that the following conditions are met:
  //
  // 1. Redistributions of source code must retain the above copyright notice, this list of
  //    conditions and the following disclaimer.
  //
  // 2. Redistributions in binary form must reproduce the above copyright notice, this list
  //    of conditions and the following disclaimer in the documentation and/or other
  //    materials provided with the distribution.
  //
  // 3. Neither the name of the copyright holder nor the names of its contributors may be
  //    used to endorse or promote products derived from this software without specific
  //    prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
  // EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
  // THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
  // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  #pragma once
  
  #include <atomic>
  
  #include "blockchain_db/blockchain_db.h"
  #include "cryptonote_basic/blobdatatype.h" // for type blobdata
  #include "ringct/rctTypes.h"
  #include <boost/thread/tss.hpp>
  
  #include <lmdb.h>
  
  #define ENABLE_AUTO_RESIZE
  
  namespace cryptonote
  {
  
  typedef struct mdb_txn_cursors
  {
    MDB_cursor *m_txc_blocks;
    MDB_cursor *m_txc_block_heights;
    MDB_cursor *m_txc_block_info;
  
    MDB_cursor *m_txc_output_txs;
    MDB_cursor *m_txc_output_amounts;
  
    MDB_cursor *m_txc_txs;
    MDB_cursor *m_txc_txs_pruned;
    MDB_cursor *m_txc_txs_prunable;
    MDB_cursor *m_txc_txs_prunable_hash;
    MDB_cursor *m_txc_tx_indices;
    MDB_cursor *m_txc_tx_outputs;
  
    MDB_cursor *m_txc_spent_keys;
  
    MDB_cursor *m_txc_txpool_meta;
    MDB_cursor *m_txc_txpool_blob;
  
    MDB_cursor *m_txc_hf_versions;
  } mdb_txn_cursors;
  
  #define m_cur_blocks	m_cursors->m_txc_blocks
  #define m_cur_block_heights	m_cursors->m_txc_block_heights
  #define m_cur_block_info	m_cursors->m_txc_block_info
  #define m_cur_output_txs	m_cursors->m_txc_output_txs
  #define m_cur_output_amounts	m_cursors->m_txc_output_amounts
  #define m_cur_txs	m_cursors->m_txc_txs
  #define m_cur_txs_pruned	m_cursors->m_txc_txs_pruned
  #define m_cur_txs_prunable	m_cursors->m_txc_txs_prunable
  #define m_cur_txs_prunable_hash	m_cursors->m_txc_txs_prunable_hash
  #define m_cur_tx_indices	m_cursors->m_txc_tx_indices
  #define m_cur_tx_outputs	m_cursors->m_txc_tx_outputs
  #define m_cur_spent_keys	m_cursors->m_txc_spent_keys
  #define m_cur_txpool_meta	m_cursors->m_txc_txpool_meta
  #define m_cur_txpool_blob	m_cursors->m_txc_txpool_blob
  #define m_cur_hf_versions	m_cursors->m_txc_hf_versions
  
  typedef struct mdb_rflags
  {
    bool m_rf_txn;
    bool m_rf_blocks;
    bool m_rf_block_heights;
    bool m_rf_block_info;
    bool m_rf_output_txs;
    bool m_rf_output_amounts;
    bool m_rf_txs;
    bool m_rf_txs_pruned;
    bool m_rf_txs_prunable;
    bool m_rf_txs_prunable_hash;
    bool m_rf_tx_indices;
    bool m_rf_tx_outputs;
    bool m_rf_spent_keys;
    bool m_rf_txpool_meta;
    bool m_rf_txpool_blob;
    bool m_rf_hf_versions;
  } mdb_rflags;
  
  typedef struct mdb_threadinfo
  {
    MDB_txn *m_ti_rtxn;	// per-thread read txn
    mdb_txn_cursors m_ti_rcursors;	// per-thread read cursors
    mdb_rflags m_ti_rflags;	// per-thread read state
  
    ~mdb_threadinfo();
  } mdb_threadinfo;
  
  struct mdb_txn_safe
  {
    mdb_txn_safe(const bool check=true);
    ~mdb_txn_safe();
  
    void commit(std::string message = "");
  
    // This should only be needed for batch transaction which must be ensured to
    // be aborted before mdb_env_close, not after. So we can't rely on
    // BlockchainLMDB destructor to call mdb_txn_safe destructor, as that's too late
    // to properly abort, since mdb_env_close would have been called earlier.
    void abort();
    void uncheck();
  
    operator MDB_txn*()
    {
      return m_txn;
    }
  
    operator MDB_txn**()
    {
      return &m_txn;
    }
  
    uint64_t num_active_tx() const;
  
    static void prevent_new_txns();
    static void wait_no_active_txns();
    static void allow_new_txns();
  
    mdb_threadinfo* m_tinfo;
    MDB_txn* m_txn;
    bool m_batch_txn = false;
    bool m_check;
    static std::atomic<uint64_t> num_active_txns;
  
    // could use a mutex here, but this should be sufficient.
    static std::atomic_flag creation_gate;
  };
  
  
  // If m_batch_active is set, a batch transaction exists beyond this class, such
  // as a batch import with verification enabled, or possibly (later) a batch
  // network sync.
  //
  // For some of the lookup methods, such as get_block_timestamp(), tx_exists(),
  // and get_tx(), when m_batch_active is set, the lookup uses the batch
  // transaction. This isn't only because the transaction is available, but it's
  // necessary so that lookups include the database updates only present in the
  // current batch write.
  //
  // A regular network sync without batch writes is expected to open a new read
  // transaction, as those lookups are part of the validation done prior to the
  // write for block and tx data, so no write transaction is open at the time.
  class BlockchainLMDB : public BlockchainDB
  {
  public:
    BlockchainLMDB(bool batch_transactions=true);
    ~BlockchainLMDB();
  
    virtual void open(const std::string& filename, const int mdb_flags=0);
  
    virtual void close();
  
    virtual void sync();
  
    virtual void safesyncmode(const bool onoff);
  
    virtual void reset();
  
    virtual std::vector<std::string> get_filenames() const;
  
    virtual bool remove_data_file(const std::string& folder) const;
  
    virtual std::string get_db_name() const;
  
    virtual bool lock();
  
    virtual void unlock();
  
    virtual bool block_exists(const crypto::hash& h, uint64_t *height = NULL) const;
  
    virtual uint64_t get_block_height(const crypto::hash& h) const;
  
    virtual block_header get_block_header(const crypto::hash& h) const;
  
    virtual cryptonote::blobdata get_block_blob(const crypto::hash& h) const;
  
    virtual cryptonote::blobdata get_block_blob_from_height(const uint64_t& height) const;
  
    virtual std::vector<uint64_t> get_block_cumulative_rct_outputs(const std::vector<uint64_t> &heights) const;
  
    virtual uint64_t get_block_timestamp(const uint64_t& height) const;
  
    virtual uint64_t get_top_block_timestamp() const;
  
    virtual size_t get_block_weight(const uint64_t& height) const;
  
    virtual difficulty_type get_block_cumulative_difficulty(const uint64_t& height) const;
  
    virtual difficulty_type get_block_difficulty(const uint64_t& height) const;
  
    virtual uint64_t get_block_already_generated_coins(const uint64_t& height) const;
  
    virtual crypto::hash get_block_hash_from_height(const uint64_t& height) const;
  
    virtual std::vector<block> get_blocks_range(const uint64_t& h1, const uint64_t& h2) const;
  
    virtual std::vector<crypto::hash> get_hashes_range(const uint64_t& h1, const uint64_t& h2) const;
  
    virtual crypto::hash top_block_hash() const;
  
    virtual block get_top_block() const;
  
    virtual uint64_t height() const;
  
    virtual bool tx_exists(const crypto::hash& h) const;
    virtual bool tx_exists(const crypto::hash& h, uint64_t& tx_index) const;
  
    virtual uint64_t get_tx_unlock_time(const crypto::hash& h) const;
  
    virtual bool get_tx_blob(const crypto::hash& h, cryptonote::blobdata &tx) const;
    virtual bool get_pruned_tx_blob(const crypto::hash& h, cryptonote::blobdata &tx) const;
    virtual bool get_prunable_tx_hash(const crypto::hash& tx_hash, crypto::hash &prunable_hash) const;
  
    virtual uint64_t get_tx_count() const;
  
    virtual std::vector<transaction> get_tx_list(const std::vector<crypto::hash>& hlist) const;
  
    virtual uint64_t get_tx_block_height(const crypto::hash& h) const;
  
    virtual uint64_t get_num_outputs(const uint64_t& amount) const;
  
    virtual output_data_t get_output_key(const uint64_t& amount, const uint64_t& index);
    virtual void get_output_key(const epee::span<const uint64_t> &amounts, const std::vector<uint64_t> &offsets, std::vector<output_data_t> &outputs, bool allow_partial = false);
  
    virtual tx_out_index get_output_tx_and_index_from_global(const uint64_t& index) const;
    virtual void get_output_tx_and_index_from_global(const std::vector<uint64_t> &global_indices,
        std::vector<tx_out_index> &tx_out_indices) const;
  
    virtual tx_out_index get_output_tx_and_index(const uint64_t& amount, const uint64_t& index) const;
    virtual void get_output_tx_and_index(const uint64_t& amount, const std::vector<uint64_t> &offsets, std::vector<tx_out_index> &indices) const;
  
    virtual std::vector<uint64_t> get_tx_amount_output_indices(const uint64_t tx_id) const;
  
    virtual bool has_key_image(const crypto::key_image& img) const;
  
    virtual void add_txpool_tx(const crypto::hash &txid, const cryptonote::blobdata &blob, const txpool_tx_meta_t& meta);
    virtual void update_txpool_tx(const crypto::hash &txid, const txpool_tx_meta_t& meta);
    virtual uint64_t get_txpool_tx_count(bool include_unrelayed_txes = true) const;
    virtual bool txpool_has_tx(const crypto::hash &txid) const;
    virtual void remove_txpool_tx(const crypto::hash& txid);
    virtual bool get_txpool_tx_meta(const crypto::hash& txid, txpool_tx_meta_t &meta) const;
    virtual bool get_txpool_tx_blob(const crypto::hash& txid, cryptonote::blobdata &bd) const;
    virtual cryptonote::blobdata get_txpool_tx_blob(const crypto::hash& txid) const;
    virtual bool for_all_txpool_txes(std::function<bool(const crypto::hash&, const txpool_tx_meta_t&, const cryptonote::blobdata*)> f, bool include_blob = false, bool include_unrelayed_txes = true) const;
  
    virtual bool for_all_key_images(std::function<bool(const crypto::key_image&)>) const;
    virtual bool for_blocks_range(const uint64_t& h1, const uint64_t& h2, std::function<bool(uint64_t, const crypto::hash&, const cryptonote::block&)>) const;
    virtual bool for_all_transactions(std::function<bool(const crypto::hash&, const cryptonote::transaction&)>, bool pruned) const;
    virtual bool for_all_outputs(std::function<bool(uint64_t amount, const crypto::hash &tx_hash, uint64_t height, size_t tx_idx)> f) const;
    virtual bool for_all_outputs(uint64_t amount, const std::function<bool(uint64_t height)> &f) const;
  
    virtual uint64_t add_block( const block& blk
                              , size_t block_weight
                              , const difficulty_type& cumulative_difficulty
                              , const uint64_t& coins_generated
                              , const std::vector<transaction>& txs
                              );
  
    virtual void set_batch_transactions(bool batch_transactions);
    virtual bool batch_start(uint64_t batch_num_blocks=0, uint64_t batch_bytes=0);
    virtual void batch_commit();
    virtual void batch_stop();
    virtual void batch_abort();
  
    virtual void block_txn_start(bool readonly);
    virtual void block_txn_stop();
    virtual void block_txn_abort();
    virtual bool block_rtxn_start(MDB_txn **mtxn, mdb_txn_cursors **mcur) const;
    virtual void block_rtxn_stop() const;
  
    virtual void pop_block(block& blk, std::vector<transaction>& txs);
  
    virtual bool can_thread_bulk_indices() const { return true; }
  
    /**
     * @brief return a histogram of outputs on the blockchain
     *
     * @param amounts optional set of amounts to lookup
     * @param unlocked whether to restrict count to unlocked outputs
     * @param recent_cutoff timestamp to determine which outputs are recent
     * @param min_count return only amounts with at least that many instances
     *
     * @return a set of amount/instances
     */
    std::map<uint64_t, std::tuple<uint64_t, uint64_t, uint64_t>> get_output_histogram(const std::vector<uint64_t> &amounts, bool unlocked, uint64_t recent_cutoff, uint64_t min_count) const;
  
    bool get_output_distribution(uint64_t amount, uint64_t from_height, uint64_t to_height, std::vector<uint64_t> &distribution, uint64_t &base) const;
  
  private:
    void do_resize(uint64_t size_increase=0);
  
    bool need_resize(uint64_t threshold_size=0) const;
    void check_and_resize_for_batch(uint64_t batch_num_blocks, uint64_t batch_bytes);
    uint64_t get_estimated_batch_size(uint64_t batch_num_blocks, uint64_t batch_bytes) const;
  
    virtual void add_block( const block& blk
                  , size_t block_weight
                  , const difficulty_type& cumulative_difficulty
                  , const uint64_t& coins_generated
                  , uint64_t num_rct_outs
                  , const crypto::hash& block_hash
                  );
  
    virtual void remove_block();
  
    virtual uint64_t add_transaction_data(const crypto::hash& blk_hash, const transaction& tx, const crypto::hash& tx_hash, const crypto::hash& tx_prunable_hash);
  
    virtual void remove_transaction_data(const crypto::hash& tx_hash, const transaction& tx);
  
    virtual uint64_t add_output(const crypto::hash& tx_hash,
        const tx_out& tx_output,
        const uint64_t& local_index,
        const uint64_t unlock_time,
        const rct::key *commitment
        );
  
    virtual void add_tx_amount_output_indices(const uint64_t tx_id,
        const std::vector<uint64_t>& amount_output_indices
        );
  
    void remove_tx_outputs(const uint64_t tx_id, const transaction& tx);
  
    void remove_output(const uint64_t amount, const uint64_t& out_index);
  
    virtual void prune_outputs(uint64_t amount);
  
    virtual void add_spent_key(const crypto::key_image& k_image);
  
    virtual void remove_spent_key(const crypto::key_image& k_image);
  
    uint64_t num_outputs() const;
  
    // Hard fork
    virtual void set_hard_fork_version(uint64_t height, uint8_t version);
    virtual uint8_t get_hard_fork_version(uint64_t height) const;
    virtual void check_hard_fork_info();
    virtual void drop_hard_fork_info();
  
    inline void check_open() const;
  
    virtual bool is_read_only() const;
  
    virtual uint64_t get_database_size() const;
  
    // fix up anything that may be wrong due to past bugs
    virtual void fixup();
  
    // migrate from older DB version to current
    void migrate(const uint32_t oldversion);
  
    // migrate from DB version 0 to 1
    void migrate_0_1();
  
    // migrate from DB version 1 to 2
    void migrate_1_2();
  
    // migrate from DB version 2 to 3
    void migrate_2_3();
  
    void cleanup_batch();
  
  private:
    MDB_env* m_env;
  
    MDB_dbi m_blocks;
    MDB_dbi m_block_heights;
    MDB_dbi m_block_info;
  
    MDB_dbi m_txs;
    MDB_dbi m_txs_pruned;
    MDB_dbi m_txs_prunable;
    MDB_dbi m_txs_prunable_hash;
    MDB_dbi m_tx_indices;
    MDB_dbi m_tx_outputs;
  
    MDB_dbi m_output_txs;
    MDB_dbi m_output_amounts;
  
    MDB_dbi m_spent_keys;
  
    MDB_dbi m_txpool_meta;
    MDB_dbi m_txpool_blob;
  
    MDB_dbi m_hf_starting_heights;
    MDB_dbi m_hf_versions;
  
    MDB_dbi m_properties;
  
    mutable uint64_t m_cum_size;	// used in batch size estimation
    mutable unsigned int m_cum_count;
    std::string m_folder;
    mdb_txn_safe* m_write_txn; // may point to either a short-lived txn or a batch txn
    mdb_txn_safe* m_write_batch_txn; // persist batch txn outside of BlockchainLMDB
    boost::thread::id m_writer;
  
    bool m_batch_transactions; // support for batch transactions
    bool m_batch_active; // whether batch transaction is in progress
  
    mdb_txn_cursors m_wcursors;
    mutable boost::thread_specific_ptr<mdb_threadinfo> m_tinfo;
  
  #if defined(__arm__)
    // force a value so it can compile with 32-bit ARM
    constexpr static uint64_t DEFAULT_MAPSIZE = 1LL << 31;
  #else
  #if defined(ENABLE_AUTO_RESIZE)
    constexpr static uint64_t DEFAULT_MAPSIZE = 1LL << 30;
  #else
    constexpr static uint64_t DEFAULT_MAPSIZE = 1LL << 33;
  #endif
  #endif
  
    constexpr static float RESIZE_PERCENT = 0.9f;
  };
  
  }  // namespace cryptonote
  