hardfork: most state now saved to the DB

There will be a delay on first load of an existing blockchain
as it gets reparsed for this state data.

10 files changed, 521 insertions, 242 deletions

diff --git a/src/blockchain_db/berkeleydb/db_bdb.cpp b/src/blockchain_db/berkeleydb/db_bdb.cpp
index a990d7aaf..2a9e9a7f8 100644
--- a/src/blockchain_db/berkeleydb/db_bdb.cpp
+++ b/src/blockchain_db/berkeleydb/db_bdb.cpp
@@ -118,6 +118,9 @@ const char* const BDB_OUTPUT_KEYS = "output_keys";
 
 const char* const BDB_SPENT_KEYS = "spent_keys";
 
+const char* const BDB_HF_STARTING_HEIGHTS = "hf_starting_heights";
+const char* const BDB_HF_VERSIONS = "hf_versions";
+
 const unsigned int MB = 1024 * 1024;
 // ND: FIXME: db keeps running out of locks when doing full syncs. Possible bug??? Set it to 5K for now.
 const unsigned int DB_MAX_LOCKS = 5000;
@@ -667,6 +670,9 @@ void BlockchainBDB::open(const std::string& filename, const int db_flags)
 
         m_spent_keys = new Db(m_env, 0);
 
+        m_hf_starting_heights = new Db(m_env, 0);
+        m_hf_versions = new Db(m_env, 0);
+
         // Tell DB about Dbs that need duplicate support
         // Note: no need to tell about sorting,
         //   as the default is insertion order, which we want
@@ -684,6 +690,9 @@ void BlockchainBDB::open(const std::string& filename, const int db_flags)
         m_output_indices->set_re_len(sizeof(uint64_t));
         m_output_keys->set_re_len(sizeof(output_data_t));
 
+        m_hf_starting_heights->set_re_len(sizeof(uint64_t));
+        m_hf_versions->set_re_len(sizeof(uint8_t));
+
         //TODO: Find out if we need to do Db::set_flags(DB_RENUMBER)
         //      for the RECNO databases.  We shouldn't as we're only
         //      inserting/removing from the end, but we'll see.
@@ -713,6 +722,9 @@ void BlockchainBDB::open(const std::string& filename, const int db_flags)
 
         m_spent_keys->open(txn, BDB_SPENT_KEYS, NULL, DB_HASH, DB_CREATE, 0);
 
+        m_hf_starting_heights->open(txn, BDB_HF_STARTING_HEIGHTS, NULL, DB_RECNO, DB_CREATE, 0);
+        m_hf_versions->open(txn, BDB_HF_VERSIONS, NULL, DB_RECNO, DB_CREATE, 0);
+
         txn.commit();
 
         DB_BTREE_STAT* stats;
@@ -785,6 +797,9 @@ void BlockchainBDB::sync()
         m_output_keys->sync(0);
 
         m_spent_keys->sync(0);
+
+        m_hf_starting_heights->sync(0);
+        m_hf_versions->sync(0);
     }
     catch (const std::exception& e)
     {
@@ -859,6 +874,12 @@ std::vector<std::string> BlockchainBDB::get_filenames() const
     m_spent_keys->get_dbname(pfname, pdbname);
     filenames.push_back(fname);
 
+    m_hf_starting_heights->get_dbname(pfname, pdbname);
+    filenames.push_back(fname);
+
+    m_hf_versions->get_dbname(pfname, pdbname);
+    filenames.push_back(fname);
+
     std::vector<std::string> full_paths;
 
     for (auto& filename : filenames)
@@ -1839,6 +1860,60 @@ void BlockchainBDB::get_output_tx_and_index(const uint64_t& amount, const std::v
     LOG_PRINT_L3("db3: " << db3);
 }
 
+void BlockchainBDB::set_hard_fork_starting_height(uint8_t version, uint64_t height)
+{
+    LOG_PRINT_L3("BlockchainBDB::" << __func__);
+    check_open();
+
+    Dbt_copy<uint8_t> val_key(version);
+    Dbt_copy<uint64_t> val(height);
+    if (m_hf_starting_heights->put(DB_DEFAULT_TX, &val_key, &val, 0))
+        throw1(DB_ERROR("Error adding hard fork starting height to db transaction."));
+}
+
+uint64_t BlockchainBDB::get_hard_fork_starting_height(uint8_t version) const
+{
+    LOG_PRINT_L3("BlockchainBDB::" << __func__);
+    check_open();
+
+    Dbt_copy<uint8_t> key(version);
+    Dbt_copy<uint64_t> result;
+
+    auto get_result = m_hf_starting_heights->get(DB_DEFAULT_TX, &key, &result, 0);
+    if (get_result == DB_NOTFOUND)
+        return std::numeric_limits<uint64_t>::max();
+    else if (get_result)
+        throw0(DB_ERROR("Error attempting to retrieve hard fork starting height from the db"));
+
+    return result;
+}
+
+void BlockchainBDB::set_hard_fork_version(uint64_t height, uint8_t version)
+{
+    LOG_PRINT_L3("BlockchainBDB::" << __func__);
+    check_open();
+
+    Dbt_copy<uint64_t> val_key(height);
+    Dbt_copy<uint8_t> val(version);
+    if (m_hf_versions->put(DB_DEFAULT_TX, &val_key, &val, 0))
+        throw1(DB_ERROR("Error adding hard fork version to db transaction."));
+}
+
+uint8_t BlockchainBDB::get_hard_fork_version(uint64_t height) const
+{
+    LOG_PRINT_L3("BlockchainBDB::" << __func__);
+    check_open();
+
+    Dbt_copy<uint64_t> key(height);
+    Dbt_copy<uint8_t> result;
+
+    auto get_result = m_hf_versions->get(DB_DEFAULT_TX, &key, &result, 0);
+    if (get_result == DB_NOTFOUND || get_result)
+        throw0(DB_ERROR("Error attempting to retrieve hard fork version from the db"));
+
+    return result;
+}
+
 void BlockchainBDB::checkpoint_worker() const
 {
     LOG_PRINT_L0("Entering BDB checkpoint thread.")
diff --git a/src/blockchain_db/berkeleydb/db_bdb.h b/src/blockchain_db/berkeleydb/db_bdb.h
index f92bbef68..54edcf0ad 100644
--- a/src/blockchain_db/berkeleydb/db_bdb.h
+++ b/src/blockchain_db/berkeleydb/db_bdb.h
@@ -374,6 +374,13 @@ private:
   virtual void remove_spent_key(const crypto::key_image& k_image);
 
   void get_output_global_indices(const uint64_t& amount, const std::vector<uint64_t> &offsets, std::vector<uint64_t> &global_indices);
+
+  // Hard fork related storage
+  virtual void set_hard_fork_starting_height(uint8_t version, uint64_t height);
+  virtual uint64_t get_hard_fork_starting_height(uint8_t version) const;
+  virtual void set_hard_fork_version(uint64_t height, uint8_t version);
+  virtual uint8_t get_hard_fork_version(uint64_t height) const;
+
   /**
    * @brief convert a tx output to a blob for storage
    *
@@ -430,6 +437,9 @@ private:
 
   Db* m_spent_keys;
 
+  Db* m_hf_starting_heights;
+  Db* m_hf_versions;
+
   uint64_t m_height;
   uint64_t m_num_outputs;
   std::string m_folder;
diff --git a/src/blockchain_db/blockchain_db.h b/src/blockchain_db/blockchain_db.h
index 25a34fc09..24bf4024d 100644
--- a/src/blockchain_db/blockchain_db.h
+++ b/src/blockchain_db/blockchain_db.h
@@ -493,6 +493,12 @@ public:
   // returns true if key image <img> is present in spent key images storage
   virtual bool has_key_image(const crypto::key_image& img) const = 0;
 
+  // Hard fork related storage
+  virtual void set_hard_fork_starting_height(uint8_t version, uint64_t height) = 0;
+  virtual uint64_t get_hard_fork_starting_height(uint8_t version) const = 0;
+  virtual void set_hard_fork_version(uint64_t height, uint8_t version) = 0;
+  virtual uint8_t get_hard_fork_version(uint64_t height) const = 0;
+
   void set_auto_remove_logs(bool auto_remove) { m_auto_remove_logs = auto_remove; }
 
   bool m_open;
diff --git a/src/blockchain_db/lmdb/db_lmdb.cpp b/src/blockchain_db/lmdb/db_lmdb.cpp
index 1583a0c06..2695d83f8 100644
--- a/src/blockchain_db/lmdb/db_lmdb.cpp
+++ b/src/blockchain_db/lmdb/db_lmdb.cpp
@@ -131,6 +131,15 @@ auto compare_uint64 = [](const MDB_val *a, const MDB_val *b)
   else return 1;
 };
 
+auto compare_uint8 = [](const MDB_val *a, const MDB_val *b)
+{
+  const uint8_t va = *(const uint8_t*)a->mv_data;
+  const uint8_t vb = *(const uint8_t*)b->mv_data;
+  if (va < vb) return -1;
+  else if (va == vb) return 0;
+  else return 1;
+};
+
 int compare_hash32(const MDB_val *a, const MDB_val *b)
 {
 	uint32_t *va = (uint32_t*) a->mv_data;
@@ -166,6 +175,9 @@ const char* const LMDB_OUTPUTS = "outputs";
 const char* const LMDB_OUTPUT_GINDICES = "output_gindices";
 const char* const LMDB_SPENT_KEYS = "spent_keys";
 
+const char* const LMDB_HF_STARTING_HEIGHTS = "hf_starting_heights";
+const char* const LMDB_HF_VERSIONS = "hf_versions";
+
 inline void lmdb_db_open(MDB_txn* txn, const char* name, int flags, MDB_dbi& dbi, const std::string& error_string)
 {
   if (mdb_dbi_open(txn, name, flags, &dbi))
@@ -1022,6 +1034,9 @@ void BlockchainLMDB::open(const std::string& filename, const int mdb_flags)
 
   lmdb_db_open(txn, LMDB_SPENT_KEYS, MDB_CREATE, m_spent_keys, "Failed to open db handle for m_spent_keys");
 
+  lmdb_db_open(txn, LMDB_HF_STARTING_HEIGHTS, MDB_CREATE, m_hf_starting_heights, "Failed to open db handle for m_hf_starting_heights");
+  lmdb_db_open(txn, LMDB_HF_VERSIONS, MDB_CREATE, m_hf_versions, "Failed to open db handle for m_hf_versions");
+
   mdb_set_dupsort(txn, m_output_amounts, compare_uint64);
   mdb_set_dupsort(txn, m_tx_outputs, compare_uint64);
   mdb_set_compare(txn, m_spent_keys, compare_hash32);
@@ -1029,6 +1044,8 @@ void BlockchainLMDB::open(const std::string& filename, const int mdb_flags)
   mdb_set_compare(txn, m_txs, compare_hash32);
   mdb_set_compare(txn, m_tx_unlocks, compare_hash32);
   mdb_set_compare(txn, m_tx_heights, compare_hash32);
+  mdb_set_compare(txn, m_hf_starting_heights, compare_uint8);
+  mdb_set_compare(txn, m_hf_versions, compare_uint64);
 
   // get and keep current height
   MDB_stat db_stats;
@@ -2347,4 +2364,111 @@ void BlockchainLMDB::get_output_tx_and_index(const uint64_t& amount, const std::
 	LOG_PRINT_L3("db3: " << db3);
 }
 
+void BlockchainLMDB::set_hard_fork_starting_height(uint8_t version, uint64_t height)
+{
+  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+  check_open();
+
+  mdb_txn_safe txn;
+  mdb_txn_safe* txn_ptr = &txn;
+  if (m_batch_active)
+    txn_ptr = m_write_txn;
+  else
+  {
+    if (mdb_txn_begin(m_env, NULL, 0, txn))
+      throw0(DB_ERROR("Failed to create a transaction for the db"));
+    txn_ptr = &txn;
+  }
+
+  MDB_val_copy<uint8_t> val_key(version);
+  MDB_val_copy<uint64_t> val_value(height);
+  if (auto result = mdb_put(*txn_ptr, m_hf_starting_heights, &val_key, &val_value, 0))
+    throw1(DB_ERROR(std::string("Error adding hard fork starting height to db transaction: ").append(mdb_strerror(result)).c_str()));
+
+  if (!m_batch_active)
+    txn.commit();
+}
+
+uint64_t BlockchainLMDB::get_hard_fork_starting_height(uint8_t version) const
+{
+  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+  check_open();
+
+  mdb_txn_safe txn;
+  mdb_txn_safe* txn_ptr = &txn;
+  if (m_batch_active)
+    txn_ptr = m_write_txn;
+  else
+  {
+    if (mdb_txn_begin(m_env, NULL, MDB_RDONLY, txn))
+      throw0(DB_ERROR("Failed to create a transaction for the db"));
+    txn_ptr = &txn;
+  }
+
+  MDB_val_copy<uint8_t> val_key(version);
+  MDB_val val_ret;
+  auto result = mdb_get(*txn_ptr, m_hf_starting_heights, &val_key, &val_ret);
+  if (result == MDB_NOTFOUND)
+    return std::numeric_limits<uint64_t>::max();
+  if (result)
+    throw0(DB_ERROR("Error attempting to retrieve a hard fork starting height from the db"));
+
+  if (!m_batch_active)
+    txn.commit();
+  return *(const uint64_t*)val_ret.mv_data;
+}
+
+void BlockchainLMDB::set_hard_fork_version(uint64_t height, uint8_t version)
+{
+  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+  check_open();
+
+//LOG_PRINT_L1("BlockchainLMDB::set_hard_fork_version: batch " << m_batch_active << ", height " << height << ", version " << (int)version);
+  mdb_txn_safe txn;
+  mdb_txn_safe* txn_ptr = &txn;
+  if (m_batch_active)
+    txn_ptr = m_write_txn;
+  else
+  {
+    if (mdb_txn_begin(m_env, NULL, 0, txn))
+      throw0(DB_ERROR("Failed to create a transaction for the db"));
+    txn_ptr = &txn;
+  }
+
+  MDB_val_copy<uint64_t> val_key(height);
+  MDB_val_copy<uint8_t> val_value(version);
+  if (auto result = mdb_put(*txn_ptr, m_hf_versions, &val_key, &val_value, 0))
+    throw1(DB_ERROR(std::string("Error adding hard fork version to db transaction: ").append(mdb_strerror(result)).c_str()));
+
+  if (!m_batch_active)
+    txn.commit();
+}
+
+uint8_t BlockchainLMDB::get_hard_fork_version(uint64_t height) const
+{
+  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+  check_open();
+
+  mdb_txn_safe txn;
+  mdb_txn_safe* txn_ptr = &txn;
+  if (m_batch_active)
+    txn_ptr = m_write_txn;
+  else
+  {
+    if (mdb_txn_begin(m_env, NULL, MDB_RDONLY, txn))
+      throw0(DB_ERROR("Failed to create a transaction for the db"));
+    txn_ptr = &txn;
+  }
+
+  MDB_val_copy<uint64_t> val_key(height);
+  MDB_val val_ret;
+  auto result = mdb_get(*txn_ptr, m_hf_versions, &val_key, &val_ret);
+  if (result == MDB_NOTFOUND || result)
+    throw0(DB_ERROR("Error attempting to retrieve a hard fork version from the db"));
+
+  if (!m_batch_active)
+    txn.commit();
+  return *(const uint8_t*)val_ret.mv_data;
+}
+
 }  // namespace cryptonote
diff --git a/src/blockchain_db/lmdb/db_lmdb.h b/src/blockchain_db/lmdb/db_lmdb.h
index b4c197803..380954295 100644
--- a/src/blockchain_db/lmdb/db_lmdb.h
+++ b/src/blockchain_db/lmdb/db_lmdb.h
@@ -238,6 +238,12 @@ private:
 
   virtual void remove_spent_key(const crypto::key_image& k_image);
 
+  // Hard fork
+  virtual void set_hard_fork_starting_height(uint8_t version, uint64_t height);
+  virtual uint64_t get_hard_fork_starting_height(uint8_t version) const;
+  virtual void set_hard_fork_version(uint64_t height, uint8_t version);
+  virtual uint8_t get_hard_fork_version(uint64_t height) const;
+
   /**
    * @brief convert a tx output to a blob for storage
    *
@@ -292,6 +298,9 @@ private:
 
   MDB_dbi m_spent_keys;
 
+  MDB_dbi m_hf_starting_heights;
+  MDB_dbi m_hf_versions;
+
   uint64_t m_height;
   uint64_t m_num_outputs;
   std::string m_folder;
diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index 2ac50aefc..65d07dcf7 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -69,10 +69,22 @@ extern "C" void slow_hash_free_state();
 
 DISABLE_VS_WARNINGS(4267)
 
+static const struct {
+  uint8_t version;
+  uint64_t height;
+  time_t time;
+} hard_forks[] = {
+  // version 1 from the start of the blockchain
+  { 1, 1, 1341378000 },
+
+  // version 2 can start from block 1009827, setup on the 20th of september
+  { 2, 1009827, 1442763710 },
+};
+
 //------------------------------------------------------------------
 Blockchain::Blockchain(tx_memory_pool& tx_pool) :
 m_db(), m_tx_pool(tx_pool), m_timestamps_and_difficulties_height(0), m_current_block_cumul_sz_limit(0), m_is_in_checkpoint_zone(false), 
-m_is_blockchain_storing(false), m_enforce_dns_checkpoints(false), m_hardfork(), m_max_prepare_blocks_threads(4), m_db_blocks_per_sync(1), m_db_sync_mode(db_async), m_fast_sync(true)
+m_is_blockchain_storing(false), m_enforce_dns_checkpoints(false), m_max_prepare_blocks_threads(4), m_db_blocks_per_sync(1), m_db_sync_mode(db_async), m_fast_sync(true)
 {
     LOG_PRINT_L3("Blockchain::" << __func__);
 }
@@ -120,7 +132,7 @@ void Blockchain::serialize(archive_t & ar, const unsigned int version)
 
     if (version > 12)
     {
-        ar & m_hardfork;
+        ar & *m_hardfork;
     }
 
     LOG_PRINT_L3("Blockchain storage:" << std::endl << "m_blocks: " << m_db->height() << std::endl << "m_blocks_index: " << m_blocks_index.size() << std::endl << "m_transactions: " << m_transactions.size() << std::endl << "dummy_key_images_container: " << dummy_key_images_container.size() << std::endl << "m_alternative_chains: " << m_alternative_chains.size() << std::endl << "m_outputs: " << m_outputs.size() << std::endl << "m_invalid_blocks: " << m_invalid_blocks.size() << std::endl << "m_current_block_cumul_sz_limit: " << m_current_block_cumul_sz_limit);
@@ -275,6 +287,11 @@ bool Blockchain::init(BlockchainDB* db, const bool testnet)
 
     m_db = db;
 
+    m_hardfork = new HardFork(*db);
+    for (size_t n = 0; n < sizeof(hard_forks) / sizeof(hard_forks[0]); ++n)
+      m_hardfork->add(hard_forks[n].version, hard_forks[n].height, hard_forks[n].time);
+    m_hardfork->init();
+
     // if the blockchain is new, add the genesis block
     // this feels kinda kludgy to do it this way, but can be looked at later.
     // TODO: add function to create and store genesis block,
@@ -355,9 +372,6 @@ bool Blockchain::init(BlockchainDB* db, const bool testnet)
     }
 #endif
 
-    // reinitialize hard fork versions, since they're not saved in the DB
-    m_hardfork.reorganize_from_chain_height (m_db, 1);
-
     LOG_PRINT_GREEN("Blockchain initialized. last block: " << m_db->height() - 1 << ", " << epee::misc_utils::get_time_interval_string(timestamp_diff) << " time ago, current difficulty: " << get_difficulty_for_next_block(), LOG_LEVEL_0);
 
     return true;
@@ -424,6 +438,7 @@ bool Blockchain::deinit()
         LOG_PRINT_L0("There was an issue closing/storing the blockchain, shutting down now to prevent issues!");
     }
 
+    delete m_hardfork;
     delete m_db;
     return true;
 }
@@ -714,7 +729,7 @@ bool Blockchain::rollback_blockchain_switching(std::list<block>& original_chain,
         CHECK_AND_ASSERT_MES(r && bvc.m_added_to_main_chain, false, "PANIC! failed to add (again) block while chain switching during the rollback!");
     }
 
-    m_hardfork.reorganize_from_chain_height(m_db, rollback_height);
+    m_hardfork->reorganize_from_chain_height(rollback_height);
 
     LOG_PRINT_L1("Rollback to height " << rollback_height << " was successful.");
     if (original_chain.size())
@@ -813,7 +828,7 @@ bool Blockchain::switch_to_alternative_blockchain(std::list<blocks_ext_by_hash::
         m_alternative_chains.erase(ch_ent);
     }
 
-    m_hardfork.reorganize_from_chain_height(m_db, split_height);
+    m_hardfork->reorganize_from_chain_height(split_height);
 
     LOG_PRINT_GREEN("REORGANIZE SUCCESS! on height: " << split_height << ", new blockchain size: " << m_db->height(), LOG_LEVEL_0);
     return true;
@@ -986,7 +1001,7 @@ bool Blockchain::create_block_template(block& b, const account_public_address& m
     CRITICAL_REGION_BEGIN(m_blockchain_lock);
     height = m_db->height();
 
-    b.major_version = m_hardfork.get_ideal_version();
+    b.major_version = m_hardfork->get_ideal_version();
     b.minor_version = 0;
     b.prev_id = get_tail_id();
     b.timestamp = time(NULL);
@@ -2259,9 +2274,9 @@ bool Blockchain::handle_block_to_main_chain(const block& bl, const crypto::hash&
     TIME_MEASURE_START(t1);
 
     // this is a cheap test
-    if (!m_hardfork.check(bl))
+    if (!m_hardfork->check(bl))
     {
-        LOG_PRINT_L1("Block with id: " << id << std::endl << "has old version: " << bl.major_version << std::endl << "current: " << m_hardfork.get_current_version());
+        LOG_PRINT_L1("Block with id: " << id << std::endl << "has old version: " << bl.major_version << std::endl << "current: " << m_hardfork->get_current_version());
         return false;
     }
 
@@ -2542,7 +2557,7 @@ bool Blockchain::handle_block_to_main_chain(const block& bl, const crypto::hash&
     update_next_cumulative_size_limit();
 
     // this will not fail since check succeeded above
-    m_hardfork.add(bl, new_height - 1);
+    m_hardfork->add(bl, new_height - 1);
 
     LOG_PRINT_L1("+++++ BLOCK SUCCESSFULLY ADDED" << std::endl << "id:\t" << id << std::endl << "PoW:\t" << proof_of_work << std::endl << "HEIGHT " << new_height << ", difficulty:\t" << current_diffic << std::endl << "block reward: " << print_money(fee_summary + base_reward) << "(" << print_money(base_reward) << " + " << print_money(fee_summary) << "), coinbase_blob_size: " << coinbase_blob_size << ", cumulative size: " << cumulative_block_size << ", " << block_processing_time << "(" << target_calculating_time << "/" << longhash_calculating_time << ")ms");
     if(m_show_time_stats)
@@ -3080,10 +3095,10 @@ void Blockchain::set_user_options(uint64_t maxthreads, uint64_t blocks_per_sync,
 
 HardFork::State Blockchain::get_hard_fork_state() const
 {
-    return m_hardfork.get_state();
+    return m_hardfork->get_state();
 }
 
 bool Blockchain::get_hard_fork_voting_info(uint8_t version, uint32_t &window, uint32_t &votes, uint32_t &threshold, uint8_t &voting) const
 {
-    return m_hardfork.get_voting_info(version, window, votes, threshold, voting);
+    return m_hardfork->get_voting_info(version, window, votes, threshold, voting);
 }
diff --git a/src/cryptonote_core/blockchain.h b/src/cryptonote_core/blockchain.h
index e549ea2d0..a248682fc 100644
--- a/src/cryptonote_core/blockchain.h
+++ b/src/cryptonote_core/blockchain.h
@@ -160,8 +160,8 @@ namespace cryptonote
     void set_show_time_stats(bool stats) { m_show_time_stats = stats; }
     
     HardFork::State get_hard_fork_state() const;
-    uint8_t get_current_hard_fork_version() const { return m_hardfork.get_current_version(); }
-    uint8_t get_ideal_hard_fork_version() const { return m_hardfork.get_ideal_version(); }
+    uint8_t get_current_hard_fork_version() const { return m_hardfork->get_current_version(); }
+    uint8_t get_ideal_hard_fork_version() const { return m_hardfork->get_ideal_version(); }
     bool get_hard_fork_voting_info(uint8_t version, uint32_t &window, uint32_t &votes, uint32_t &threshold, uint8_t &voting) const;
 
     BlockchainDB& get_db()
@@ -233,7 +233,7 @@ namespace cryptonote
     std::atomic<bool> m_is_blockchain_storing;
     bool m_enforce_dns_checkpoints;
 
-    HardFork m_hardfork;
+    HardFork *m_hardfork;
 
     template<class visitor_t>
     inline bool scan_outputkeys_for_indexes(const txin_to_key& tx_in_to_key, visitor_t &vis, const crypto::hash &tx_prefix_hash, uint64_t* pmax_related_block_height = NULL) const;
diff --git a/src/cryptonote_core/hardfork.cpp b/src/cryptonote_core/hardfork.cpp
index 3003e74c8..d2e95b58e 100644
--- a/src/cryptonote_core/hardfork.cpp
+++ b/src/cryptonote_core/hardfork.cpp
@@ -35,15 +35,14 @@
 
 using namespace cryptonote;
 
-HardFork::HardFork(uint8_t original_version, time_t forked_time, time_t update_time, uint64_t max_history, int threshold_percent, uint64_t checkpoint_period):
+HardFork::HardFork(cryptonote::BlockchainDB &db, uint8_t original_version, time_t forked_time, time_t update_time, uint64_t window_size, int threshold_percent):
+  db(db),
   original_version(original_version),
   forked_time(forked_time),
   update_time(update_time),
-  max_history(max_history),
-  threshold_percent(threshold_percent),
-  checkpoint_period(checkpoint_period)
+  window_size(window_size),
+  threshold_percent(threshold_percent)
 {
-  init();
 }
 
 bool HardFork::add(uint8_t version, uint64_t height, time_t time)
@@ -96,7 +95,7 @@ bool HardFork::add(const cryptonote::block &block, uint64_t height)
 
   const uint8_t version = get_effective_version(block);
 
-  while (versions.size() >= max_history) {
+  while (versions.size() >= window_size) {
     const uint8_t old_version = versions.front();
     last_versions[old_version]--;
     assert(last_versions[old_version] >= 0);
@@ -109,13 +108,12 @@ bool HardFork::add(const cryptonote::block &block, uint64_t height)
   uint8_t voted = get_voted_fork_index(height);
   if (voted > current_fork_index) {
     for (int v = heights[current_fork_index].version + 1; v <= heights[voted].version; ++v) {
-      starting[v] = height;
+      db.set_hard_fork_starting_height(v, height);
     }
     current_fork_index = voted;
   }
 
-  if (height % checkpoint_period == 0)
-    checkpoints.push_back(std::make_pair(height, current_fork_index));
+  db.set_hard_fork_version(height, heights[current_fork_index].version);
 
   return true;
 }
@@ -126,59 +124,66 @@ void HardFork::init()
   versions.clear();
   for (size_t n = 0; n < 256; ++n)
     last_versions[n] = 0;
-  for (size_t n = 0; n < 256; ++n)
-    starting[n] = std::numeric_limits<uint64_t>::max();
-  add(original_version, 0, 0);
-  for (size_t n = 0; n <= original_version; ++n)
-    starting[n] = 0;
-  checkpoints.clear();
   current_fork_index = 0;
-  vote_threshold = (uint32_t)ceilf(max_history * threshold_percent / 100.0f);
+  vote_threshold = (uint32_t)ceilf(window_size * threshold_percent / 100.0f);
+
+  // restore state from DB
+  uint64_t height = db.height();
+  if (height > window_size)
+    height -= window_size;
+  else
+    height = 1;
+
+  bool populate = db.get_hard_fork_starting_height(original_version) == std::numeric_limits<uint64_t>::max();
+  if (populate) {
+    LOG_PRINT_L0("The DB has no hard fork info, reparsing from start");
+    height = 1;
+  }
+  LOG_PRINT_L1("reorganizing from " << height);
+  reorganize_from_chain_height(height);
+  if (populate) {
+    // reorg will not touch the genesis block, use this as a flag for populating done
+    db.set_hard_fork_version(0, original_version);
+    db.set_hard_fork_starting_height(original_version, 0);
+  }
+  LOG_PRINT_L1("reorganization done");
 }
 
-bool HardFork::reorganize_from_block_height(const cryptonote::BlockchainDB *db, uint64_t height)
+bool HardFork::reorganize_from_block_height(uint64_t height)
 {
   CRITICAL_REGION_LOCAL(lock);
-  if (!db || height >= db->height())
+  if (height >= db.height())
     return false;
-  while (!checkpoints.empty() && checkpoints.back().first > height)
-    checkpoints.pop_back();
+
   versions.clear();
 
-  int v;
-  for (v = 255; v >= 0; --v) {
-    if (starting[v] <= height)
-      break;
-    if (starting[v] != std::numeric_limits<uint64_t>::max()) {
-      starting[v] = std::numeric_limits<uint64_t>::max();
-    }
-  }
-  for (current_fork_index = 0; current_fork_index < heights.size(); ++current_fork_index) {
-    if (heights[current_fork_index].version == v)
-      break;
-  }
   for (size_t n = 0; n < 256; ++n)
     last_versions[n] = 0;
-  const uint64_t rescan_height = height >= (max_history - 1) ? height - (max_history - 1) : 0;
+  const uint64_t rescan_height = height >= (window_size - 1) ? height - (window_size - 1) : 0;
+  const uint8_t start_version = height == 0 ? original_version : db.get_hard_fork_version(height);
+  while (heights[current_fork_index].version > start_version) {
+    db.set_hard_fork_starting_height(heights[current_fork_index].version, std::numeric_limits<uint64_t>::max());
+    --current_fork_index;
+  }
   for (uint64_t h = rescan_height; h <= height; ++h) {
-    cryptonote::block b = db->get_block_from_height(h);
+    cryptonote::block b = db.get_block_from_height(h);
     const uint8_t v = get_effective_version(b);
     last_versions[v]++;
     versions.push_back(v);
   }
-  const uint64_t bc_height = db->height();
+  const uint64_t bc_height = db.height();
   for (uint64_t h = height + 1; h < bc_height; ++h) {
-    add(db->get_block_from_height(h), h);
+    add(db.get_block_from_height(h), h);
   }
 
   return true;
 }
 
-bool HardFork::reorganize_from_chain_height(const cryptonote::BlockchainDB *db, uint64_t height)
+bool HardFork::reorganize_from_chain_height(uint64_t height)
 {
   if (height == 0)
     return false;
-  return reorganize_from_block_height(db, height - 1);
+  return reorganize_from_block_height(height - 1);
 }
 
 int HardFork::get_voted_fork_index(uint64_t height) const
@@ -219,18 +224,17 @@ HardFork::State HardFork::get_state() const
 uint8_t HardFork::get(uint64_t height) const
 {
   CRITICAL_REGION_LOCAL(lock);
-  for (size_t n = 1; n < 256; ++n) {
-    if (starting[n] > height)
-      return n - 1;
+  if (height > db.height()) {
+    assert(false);
+    return 255;
   }
-  assert(false);
-  return 255;
+  return db.get_hard_fork_version(height);
 }
 
 uint64_t HardFork::get_start_height(uint8_t version) const
 {
   CRITICAL_REGION_LOCAL(lock);
-  return starting[version];
+  return db.get_hard_fork_starting_height(version);
 }
 
 uint8_t HardFork::get_current_version() const
@@ -261,20 +265,3 @@ bool HardFork::get_voting_info(uint8_t version, uint32_t &window, uint32_t &vote
   return enabled;
 }
 
-template<class archive_t>
-void HardFork::serialize(archive_t & ar, const unsigned int version)
-{
-  CRITICAL_REGION_LOCAL(lock);
-  ar & forked_time;
-  ar & update_time;
-  ar & max_history;
-  ar & threshold_percent;
-  ar & original_version;
-  ar & heights;
-  ar & last_versions;
-  ar & starting;
-  ar & current_fork_index;
-  ar & vote_threshold;
-  ar & checkpoint_period;
-  ar & checkpoints;
-}
diff --git a/src/cryptonote_core/hardfork.h b/src/cryptonote_core/hardfork.h
index 3bcf46cff..bdac87f2c 100644
--- a/src/cryptonote_core/hardfork.h
+++ b/src/cryptonote_core/hardfork.h
@@ -28,8 +28,6 @@
 
 #pragma once
 
-#include <boost/serialization/serialization.hpp>
-#include <boost/serialization/version.hpp>
 #include "syncobj.h"
 #include "cryptonote_core/cryptonote_basic.h"
 
@@ -48,9 +46,8 @@ namespace cryptonote
 
     static const time_t DEFAULT_FORKED_TIME = 31557600; // a year in seconds
     static const time_t DEFAULT_UPDATE_TIME = 31557600 / 2;
-    static const uint64_t DEFAULT_MAX_HISTORY = 50; // supermajority window check length
+    static const uint64_t DEFAULT_WINDOW_SIZE = 50; // supermajority window check length
     static const int DEFAULT_THRESHOLD_PERCENT = 80;
-    static const uint64_t DEFAULT_CHECKPOINT_PERIOD = 1024; // mark a checkpoint every that many blocks
 
     /**
      * @brief creates a new HardFork object
@@ -58,10 +55,10 @@ namespace cryptonote
      * @param original_version the block version for blocks 0 through to the first fork
      * @param forked_time the time in seconds before thinking we're forked
      * @param update_time the time in seconds before thinking we need to update
-     * @param max_history the size of the window in blocks to consider for version voting
+     * @param window_size the size of the window in blocks to consider for version voting
      * @param threshold_percent the size of the majority in percents
      */
-    HardFork(uint8_t original_version = 1, time_t forked_time = DEFAULT_FORKED_TIME, time_t update_time = DEFAULT_UPDATE_TIME, uint64_t max_history = DEFAULT_MAX_HISTORY, int threshold_percent = DEFAULT_THRESHOLD_PERCENT, uint64_t checkpoint_period = DEFAULT_CHECKPOINT_PERIOD);
+    HardFork(cryptonote::BlockchainDB &db, uint8_t original_version = 1, time_t forked_time = DEFAULT_FORKED_TIME, time_t update_time = DEFAULT_UPDATE_TIME, uint64_t window_size = DEFAULT_WINDOW_SIZE, int threshold_percent = DEFAULT_THRESHOLD_PERCENT);
 
     /**
      * @brief add a new hardfork height
@@ -75,6 +72,13 @@ namespace cryptonote
     bool add(uint8_t version, uint64_t height, time_t time);
 
     /**
+     * @brief initialize the object
+     *
+     * Must be done after adding all the required hardforks via add above
+     */
+    void init();
+
+    /**
      * @brief check whether a new block would be accepted
      *
      * returns true if the block is accepted, false otherwise
@@ -91,9 +95,7 @@ namespace cryptonote
      * call add first, then, if the hard fork requirements are met,
      * add the block to the blockchain, upon which a failure (the
      * block being invalid, double spending, etc) would cause the
-     * hardfork object to rescan the blockchain versions past the
-     * last checkpoint, potentially causing a large number of DB
-     * operations.
+     * hardfork object to reorganize.
      */
     bool check(const cryptonote::block &block) const;
 
@@ -117,8 +119,8 @@ namespace cryptonote
      * @param blockchain the blockchain
      * @param height of the last block kept from the previous blockchain
      */
-    bool reorganize_from_block_height(const cryptonote::BlockchainDB *db, uint64_t height);
-    bool reorganize_from_chain_height(const cryptonote::BlockchainDB *db, uint64_t height);
+    bool reorganize_from_block_height(uint64_t height);
+    bool reorganize_from_chain_height(uint64_t height);
 
     /**
      * @brief returns current state at the given time
@@ -176,23 +178,21 @@ namespace cryptonote
     /**
      * @brief returns the size of the voting window in blocks
      */
-    uint64_t get_window_size() const { return max_history; }
-
-    template<class archive_t>
-    void serialize(archive_t & ar, const unsigned int version);
+    uint64_t get_window_size() const { return window_size; }
 
   private:
 
-    void init();
     bool do_check(const cryptonote::block &block) const;
     int get_voted_fork_index(uint64_t height) const;
     uint8_t get_effective_version(const cryptonote::block &block) const;
 
   private:
 
+    BlockchainDB &db;
+
     time_t forked_time;
     time_t update_time;
-    uint64_t max_history;
+    uint64_t window_size;
     int threshold_percent;
 
     uint8_t original_version;
@@ -206,16 +206,11 @@ namespace cryptonote
 
     std::deque<uint8_t> versions; /* rolling window of the last N blocks' versions */
     unsigned int last_versions[256]; /* count of the block versions in the last N blocks */
-    uint64_t starting[256]; /* block height at which each fork starts */
-    unsigned int current_fork_index;
+    uint32_t current_fork_index;
     uint32_t vote_threshold;
 
-    uint64_t checkpoint_period;
-    std::vector<std::pair<uint64_t, int>> checkpoints;
-
     mutable epee::critical_section lock;
   };
 
 }  // namespace cryptonote
 
-BOOST_CLASS_VERSION(cryptonote::HardFork, 1)
diff --git a/tests/unit_tests/hardfork.cpp b/tests/unit_tests/hardfork.cpp
index 6b3c332a8..ad00ed60f 100644
--- a/tests/unit_tests/hardfork.cpp
+++ b/tests/unit_tests/hardfork.cpp
@@ -39,6 +39,97 @@ using namespace cryptonote;
 #define BLOCKS_PER_YEAR 525960
 #define SECONDS_PER_YEAR 31557600
 
+
+class TestDB: public BlockchainDB {
+public:
+  virtual void open(const std::string& filename, const int db_flags = 0) {
+    for (size_t n = 0; n < 256; ++n)
+      starting_height[n] = std::numeric_limits<uint64_t>::max();
+  }
+  virtual void close() {}
+  virtual void sync() {}
+  virtual void reset() {}
+  virtual std::vector<std::string> get_filenames() const { return std::vector<std::string>(); }
+  virtual std::string get_db_name() const { return std::string(); }
+  virtual bool lock() { return true; }
+  virtual void unlock() { }
+  virtual void batch_start(uint64_t batch_num_blocks=0) {}
+  virtual void batch_stop() {}
+  virtual void set_batch_transactions(bool) {}
+  virtual bool block_exists(const crypto::hash& h) const { return false; }
+  virtual block get_block(const crypto::hash& h) const { return block(); }
+  virtual uint64_t get_block_height(const crypto::hash& h) const { return 0; }
+  virtual block_header get_block_header(const crypto::hash& h) const { return block_header(); }
+  virtual uint64_t get_block_timestamp(const uint64_t& height) const { return 0; }
+  virtual uint64_t get_top_block_timestamp() const { return 0; }
+  virtual size_t get_block_size(const uint64_t& height) const { return 128; }
+  virtual difficulty_type get_block_cumulative_difficulty(const uint64_t& height) const { return 10; }
+  virtual difficulty_type get_block_difficulty(const uint64_t& height) const { return 0; }
+  virtual uint64_t get_block_already_generated_coins(const uint64_t& height) const { return 10000000000; }
+  virtual crypto::hash get_block_hash_from_height(const uint64_t& height) const { return crypto::hash(); }
+  virtual std::vector<block> get_blocks_range(const uint64_t& h1, const uint64_t& h2) const { return std::vector<block>(); }
+  virtual std::vector<crypto::hash> get_hashes_range(const uint64_t& h1, const uint64_t& h2) const { return std::vector<crypto::hash>(); }
+  virtual crypto::hash top_block_hash() const { return crypto::hash(); }
+  virtual block get_top_block() const { return block(); }
+  virtual uint64_t height() const { return blocks.size(); }
+  virtual bool tx_exists(const crypto::hash& h) const { return false; }
+  virtual uint64_t get_tx_unlock_time(const crypto::hash& h) const { return 0; }
+  virtual transaction get_tx(const crypto::hash& h) const { return transaction(); }
+  virtual uint64_t get_tx_count() const { return 0; }
+  virtual std::vector<transaction> get_tx_list(const std::vector<crypto::hash>& hlist) const { return std::vector<transaction>(); }
+  virtual uint64_t get_tx_block_height(const crypto::hash& h) const { return 0; }
+  virtual uint64_t get_num_outputs(const uint64_t& amount) const { return 1; }
+  virtual output_data_t get_output_key(const uint64_t& amount, const uint64_t& index) { return output_data_t(); }
+  virtual output_data_t get_output_key(const uint64_t& global_index) const { return output_data_t(); }
+  virtual tx_out get_output(const crypto::hash& h, const uint64_t& index) const { return tx_out(); }
+  virtual tx_out_index get_output_tx_and_index_from_global(const uint64_t& index) const { return tx_out_index(); }
+  virtual tx_out_index get_output_tx_and_index(const uint64_t& amount, const uint64_t& index) { return tx_out_index(); }
+  virtual void get_output_tx_and_index(const uint64_t& amount, const std::vector<uint64_t> &offsets, std::vector<tx_out_index> &indices) {}
+  virtual void get_output_key(const uint64_t &amount, const std::vector<uint64_t> &offsets, std::vector<output_data_t> &outputs) {}
+  virtual bool can_thread_bulk_indices() const { return false; }
+  virtual std::vector<uint64_t> get_tx_output_indices(const crypto::hash& h) const { return std::vector<uint64_t>(); }
+  virtual std::vector<uint64_t> get_tx_amount_output_indices(const crypto::hash& h) const { return std::vector<uint64_t>(); }
+  virtual bool has_key_image(const crypto::key_image& img) const { return false; }
+  virtual void remove_block() { blocks.pop_back(); }
+  virtual void add_transaction_data(const crypto::hash& blk_hash, const transaction& tx, const crypto::hash& tx_hash) {}
+  virtual void remove_transaction_data(const crypto::hash& tx_hash, const transaction& tx) {}
+  virtual void add_output(const crypto::hash& tx_hash, const tx_out& tx_output, const uint64_t& local_index, const uint64_t unlock_time) {}
+  virtual void remove_output(const tx_out& tx_output) {}
+  virtual void add_spent_key(const crypto::key_image& k_image) {}
+  virtual void remove_spent_key(const crypto::key_image& k_image) {}
+
+  virtual void add_block( const block& blk
+                        , const size_t& block_size
+                        , const difficulty_type& cumulative_difficulty
+                        , const uint64_t& coins_generated
+                        , const crypto::hash& blk_hash
+                        ) {
+    blocks.push_back(blk);
+  }
+  virtual block get_block_from_height(const uint64_t& height) const {
+    return blocks[height];
+  }
+  virtual void set_hard_fork_starting_height(uint8_t version, uint64_t height) {
+    starting_height[version] = height;
+  }
+  virtual uint64_t get_hard_fork_starting_height(uint8_t version) const {
+    return starting_height[version];
+  }
+  virtual void set_hard_fork_version(uint64_t height, uint8_t version) {
+    printf("set_hard_fork_version(%lu, %u)\n", (unsigned long)height, version);
+    if (versions.size() <= height) versions.resize(height+1); versions[height] = version;
+  }
+  virtual uint8_t get_hard_fork_version(uint64_t height) const {
+    printf("get_hard_fork_version(%lu)\n", (unsigned long)height);
+    return versions[height];
+  }
+
+private:
+  std::vector<block> blocks;
+  uint64_t starting_height[256];
+  std::deque<uint8_t> versions;
+};
+
 static cryptonote::block mkblock(uint8_t version)
 {
   cryptonote::block b;
@@ -48,19 +139,27 @@ static cryptonote::block mkblock(uint8_t version)
 
 TEST(empty_hardforks, Success)
 {
-  HardFork hf;
+  TestDB db;
+  HardFork hf(db);
 
+  ASSERT_TRUE(hf.add(1, 0, 0));
+  hf.init();
   ASSERT_TRUE(hf.get_state(time(NULL)) == HardFork::Ready);
   ASSERT_TRUE(hf.get_state(time(NULL) + 3600*24*400) == HardFork::Ready);
 
+  for (uint64_t h = 0; h <= 10; ++h) {
+    db.add_block(mkblock(1), 0, 0, 0, crypto::hash());
+    ASSERT_TRUE(hf.add(db.get_block_from_height(h), h));
+  }
   ASSERT_EQ(hf.get(0), 1);
   ASSERT_EQ(hf.get(1), 1);
-  ASSERT_EQ(hf.get(100000000), 1);
+  ASSERT_EQ(hf.get(10), 1);
 }
 
 TEST(ordering, Success)
 {
-  HardFork hf;
+  TestDB db;
+  HardFork hf(db);
 
   ASSERT_TRUE(hf.add(2, 2, 1));
   ASSERT_FALSE(hf.add(3, 3, 1));
@@ -73,8 +172,10 @@ TEST(ordering, Success)
 
 TEST(states, Success)
 {
-  HardFork hf;
+  TestDB db;
+  HardFork hf(db);
 
+  ASSERT_TRUE(hf.add(1, 0, 0));
   ASSERT_TRUE(hf.add(2, BLOCKS_PER_YEAR, SECONDS_PER_YEAR));
 
   ASSERT_TRUE(hf.get_state(0) == HardFork::Ready);
@@ -94,15 +195,20 @@ TEST(states, Success)
 
 TEST(steps_asap, Success)
 {
-  HardFork hf(1,1,1,1);
+  TestDB db;
+  HardFork hf(db, 1,1,1,1);
 
   //                 v  h  t
+  ASSERT_TRUE(hf.add(1, 0, 0));
   ASSERT_TRUE(hf.add(4, 2, 1));
   ASSERT_TRUE(hf.add(7, 4, 2));
   ASSERT_TRUE(hf.add(9, 6, 3));
+  hf.init();
 
-  for (uint64_t h = 0; h < 10; ++h)
-    hf.add(mkblock(10), h);
+  for (uint64_t h = 0; h < 10; ++h) {
+    db.add_block(mkblock(10), 0, 0, 0, crypto::hash());
+    ASSERT_TRUE(hf.add(db.get_block_from_height(h), h));
+  }
 
   ASSERT_EQ(hf.get(0), 1);
   ASSERT_EQ(hf.get(1), 1);
@@ -114,195 +220,142 @@ TEST(steps_asap, Success)
   ASSERT_EQ(hf.get(7), 9);
   ASSERT_EQ(hf.get(8), 9);
   ASSERT_EQ(hf.get(9), 9);
-  ASSERT_EQ(hf.get(100000), 9);
 }
 
 TEST(steps_1, Success)
 {
-  HardFork hf(1,1,1,1);
+  TestDB db;
+  HardFork hf(db, 1,1,1,1);
 
-  //                 v  h  t
+  ASSERT_TRUE(hf.add(1, 0, 0));
   for (int n = 1 ; n < 10; ++n)
     ASSERT_TRUE(hf.add(n+1, n, n));
+  hf.init();
+
+  for (uint64_t h = 0 ; h < 10; ++h) {
+    db.add_block(mkblock(h+1), 0, 0, 0, crypto::hash());
+    ASSERT_TRUE(hf.add(db.get_block_from_height(h), h));
+  }
 
   for (uint64_t h = 0; h < 10; ++h) {
-    hf.add(mkblock(h+1), h);
     ASSERT_EQ(hf.get(h), h+1);
   }
 }
 
-class TestDB: public BlockchainDB {
-public:
-  virtual void open(const std::string& filename, const int db_flags = 0) {}
-  virtual void close() {}
-  virtual void sync() {}
-  virtual void reset() {}
-  virtual std::vector<std::string> get_filenames() const { return std::vector<std::string>(); }
-  virtual std::string get_db_name() const { return std::string(); }
-  virtual bool lock() { return true; }
-  virtual void unlock() { }
-  virtual void batch_start(uint64_t batch_num_blocks=0) {}
-  virtual void batch_stop() {}
-  virtual void set_batch_transactions(bool) {}
-  virtual bool block_exists(const crypto::hash& h) const { return false; }
-  virtual block get_block(const crypto::hash& h) const { return block(); }
-  virtual uint64_t get_block_height(const crypto::hash& h) const { return 0; }
-  virtual block_header get_block_header(const crypto::hash& h) const { return block_header(); }
-  virtual uint64_t get_block_timestamp(const uint64_t& height) const { return 0; }
-  virtual uint64_t get_top_block_timestamp() const { return 0; }
-  virtual size_t get_block_size(const uint64_t& height) const { return 128; }
-  virtual difficulty_type get_block_cumulative_difficulty(const uint64_t& height) const { return 10; }
-  virtual difficulty_type get_block_difficulty(const uint64_t& height) const { return 0; }
-  virtual uint64_t get_block_already_generated_coins(const uint64_t& height) const { return 10000000000; }
-  virtual crypto::hash get_block_hash_from_height(const uint64_t& height) const { return crypto::hash(); }
-  virtual std::vector<block> get_blocks_range(const uint64_t& h1, const uint64_t& h2) const { return std::vector<block>(); }
-  virtual std::vector<crypto::hash> get_hashes_range(const uint64_t& h1, const uint64_t& h2) const { return std::vector<crypto::hash>(); }
-  virtual crypto::hash top_block_hash() const { return crypto::hash(); }
-  virtual block get_top_block() const { return block(); }
-  virtual uint64_t height() const { return blocks.size(); }
-  virtual bool tx_exists(const crypto::hash& h) const { return false; }
-  virtual uint64_t get_tx_unlock_time(const crypto::hash& h) const { return 0; }
-  virtual transaction get_tx(const crypto::hash& h) const { return transaction(); }
-  virtual uint64_t get_tx_count() const { return 0; }
-  virtual std::vector<transaction> get_tx_list(const std::vector<crypto::hash>& hlist) const { return std::vector<transaction>(); }
-  virtual uint64_t get_tx_block_height(const crypto::hash& h) const { return 0; }
-  virtual uint64_t get_num_outputs(const uint64_t& amount) const { return 1; }
-  virtual output_data_t get_output_key(const uint64_t& amount, const uint64_t& index) { return output_data_t(); }
-  virtual output_data_t get_output_key(const uint64_t& global_index) const { return output_data_t(); }
-  virtual tx_out get_output(const crypto::hash& h, const uint64_t& index) const { return tx_out(); }
-  virtual tx_out_index get_output_tx_and_index_from_global(const uint64_t& index) const { return tx_out_index(); }
-  virtual tx_out_index get_output_tx_and_index(const uint64_t& amount, const uint64_t& index) { return tx_out_index(); }
-  virtual void get_output_tx_and_index(const uint64_t& amount, const std::vector<uint64_t> &offsets, std::vector<tx_out_index> &indices) {}
-  virtual void get_output_key(const uint64_t &amount, const std::vector<uint64_t> &offsets, std::vector<output_data_t> &outputs) {}
-  virtual bool can_thread_bulk_indices() const { return false; }
-  virtual std::vector<uint64_t> get_tx_output_indices(const crypto::hash& h) const { return std::vector<uint64_t>(); }
-  virtual std::vector<uint64_t> get_tx_amount_output_indices(const crypto::hash& h) const { return std::vector<uint64_t>(); }
-  virtual bool has_key_image(const crypto::key_image& img) const { return false; }
-  virtual void remove_block() { blocks.pop_back(); }
-  virtual void add_transaction_data(const crypto::hash& blk_hash, const transaction& tx, const crypto::hash& tx_hash) {}
-  virtual void remove_transaction_data(const crypto::hash& tx_hash, const transaction& tx) {}
-  virtual void add_output(const crypto::hash& tx_hash, const tx_out& tx_output, const uint64_t& local_index, const uint64_t unlock_time) {}
-  virtual void remove_output(const tx_out& tx_output) {}
-  virtual void add_spent_key(const crypto::key_image& k_image) {}
-  virtual void remove_spent_key(const crypto::key_image& k_image) {}
-
-  virtual void add_block( const block& blk
-                        , const size_t& block_size
-                        , const difficulty_type& cumulative_difficulty
-                        , const uint64_t& coins_generated
-                        , const crypto::hash& blk_hash
-                        ) {
-    blocks.push_back(blk);
-  }
-  virtual block get_block_from_height(const uint64_t& height) const {
-    return blocks[height];
-  }
-private:
-  std::vector<block> blocks;
-};
-
 TEST(reorganize, Same)
 {
   for (int history = 1; history <= 12; ++history) {
-    for (uint64_t checkpoint_period = 1; checkpoint_period <= 16; checkpoint_period++) {
-      HardFork hf(1, 1, 1, history, 100, checkpoint_period);
-      TestDB db;
-
-      //                 v  h  t
-      ASSERT_TRUE(hf.add(4, 2, 1));
-      ASSERT_TRUE(hf.add(7, 4, 2));
-      ASSERT_TRUE(hf.add(9, 6, 3));
-
-      //                                 index  0  1  2  3  4  5  6  7  8  9
-      static const uint8_t block_versions[] = { 1, 1, 4, 4, 7, 7, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9 };
-      for (uint64_t h = 0; h < 20; ++h) {
-        db.add_block(mkblock(block_versions[h]), 0, 0, 0, crypto::hash());
-        hf.add(db.get_block_from_height(h), h);
-      }
-
-      for (uint64_t rh = 0; rh < 20; ++rh) {
-        hf.reorganize_from_block_height(&db, rh);
-        for (int hh = 0; hh < 20; ++hh) {
-          uint8_t version = hh >= (history-1) ? block_versions[hh - (history-1)] : 1;
-          ASSERT_EQ(hf.get(hh), version);
-        }
-        ASSERT_EQ(hf.get(100000), 9);
-      }
-    }
-  }
-}
-
-TEST(reorganize, Changed)
-{
-  int history = 4;
-  for (uint64_t checkpoint_period = 1; checkpoint_period <= 16; checkpoint_period++) {
-    HardFork hf(1, 1, 1, 4, 100, checkpoint_period);
     TestDB db;
+    HardFork hf(db, 1, 1, 1, history, 100);
 
     //                 v  h  t
+    ASSERT_TRUE(hf.add(1, 0, 0));
     ASSERT_TRUE(hf.add(4, 2, 1));
     ASSERT_TRUE(hf.add(7, 4, 2));
     ASSERT_TRUE(hf.add(9, 6, 3));
+    hf.init();
 
     //                                 index  0  1  2  3  4  5  6  7  8  9
     static const uint8_t block_versions[] = { 1, 1, 4, 4, 7, 7, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9 };
     for (uint64_t h = 0; h < 20; ++h) {
       db.add_block(mkblock(block_versions[h]), 0, 0, 0, crypto::hash());
-      hf.add(db.get_block_from_height(h), h);
+      ASSERT_TRUE(hf.add(db.get_block_from_height(h), h));
     }
 
     for (uint64_t rh = 0; rh < 20; ++rh) {
-      hf.reorganize_from_block_height(&db, rh);
+      hf.reorganize_from_block_height(rh);
       for (int hh = 0; hh < 20; ++hh) {
         uint8_t version = hh >= (history-1) ? block_versions[hh - (history-1)] : 1;
         ASSERT_EQ(hf.get(hh), version);
       }
-      ASSERT_EQ(hf.get(100000), 9);
     }
+  }
+}
 
-    // delay a bit for 9, and go back to 1 to check it stays at 9
-    static const uint8_t block_versions_new[] =    { 1, 1, 4, 4, 7, 7, 4, 7, 7, 7, 9, 9, 9, 9, 9, 1, 1, 1, 1, 1 };
-    static const uint8_t expected_versions_new[] = { 1, 1, 1, 1, 1, 4, 4, 4, 4, 4, 7, 7, 7, 9, 9, 9, 9, 9, 9, 9 };
-    for (uint64_t h = 3; h < 20; ++h) {
-      db.remove_block();
-    }
-    ASSERT_EQ(db.height(), 3);
-    hf.reorganize_from_block_height(&db, 2);
-    for (uint64_t h = 3; h < 20; ++h) {
-      db.add_block(mkblock(block_versions_new[h]), 0, 0, 0, crypto::hash());
-      hf.add(db.get_block_from_height(h), h);
-    }
-    for (int hh = 0; hh < 20; ++hh) {
-      ASSERT_EQ(hf.get(hh), expected_versions_new[hh]);
+TEST(reorganize, Changed)
+{
+  int history = 4;
+  TestDB db;
+  HardFork hf(db, 1, 1, 1, 4, 100);
+
+  //                 v  h  t
+  ASSERT_TRUE(hf.add(1, 0, 0));
+  ASSERT_TRUE(hf.add(4, 2, 1));
+  ASSERT_TRUE(hf.add(7, 4, 2));
+  ASSERT_TRUE(hf.add(9, 6, 3));
+  hf.init();
+
+  //                                 index  0  1  2  3  4  5  6  7  8  9
+  static const uint8_t block_versions[] = { 1, 1, 4, 4, 7, 7, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9 };
+  for (uint64_t h = 0; h < 16; ++h) {
+    db.add_block(mkblock(block_versions[h]), 0, 0, 0, crypto::hash());
+    ASSERT_TRUE (hf.add(db.get_block_from_height(h), h));
+  }
+
+  for (uint64_t rh = 0; rh < 16; ++rh) {
+    hf.reorganize_from_block_height(rh);
+    for (int hh = 0; hh < 16; ++hh) {
+      uint8_t version = hh >= (history-1) ? block_versions[hh - (history-1)] : 1;
+      ASSERT_EQ(hf.get(hh), version);
     }
-    ASSERT_EQ(hf.get(100000), 9);
+  }
+
+  // delay a bit for 9, and go back to 1 to check it stays at 9
+  static const uint8_t block_versions_new[] =    { 1, 1, 4, 4, 7, 7, 4, 7, 7, 7, 9, 9, 9, 9, 9, 1 };
+  static const uint8_t expected_versions_new[] = { 1, 1, 1, 1, 1, 4, 4, 4, 4, 4, 7, 7, 7, 9, 9, 9 };
+  for (uint64_t h = 3; h < 16; ++h) {
+    db.remove_block();
+  }
+  ASSERT_EQ(db.height(), 3);
+  hf.reorganize_from_block_height(2);
+  for (uint64_t h = 3; h < 16; ++h) {
+    db.add_block(mkblock(block_versions_new[h]), 0, 0, 0, crypto::hash());
+    bool ret = hf.add(db.get_block_from_height(h), h);
+    ASSERT_EQ (ret, h < 15);
+  }
+  db.remove_block(); // last block added to the blockchain, but not hf
+  ASSERT_EQ(db.height(), 15);
+  for (int hh = 0; hh < 15; ++hh) {
+    ASSERT_EQ(hf.get(hh), expected_versions_new[hh]);
   }
 }
 
 TEST(voting, threshold)
 {
   for (int threshold = 87; threshold <= 88; ++threshold) {
-    HardFork hf(1, 1, 1, 8, threshold, 10);
     TestDB db;
+    HardFork hf(db, 1, 1, 1, 8, threshold);
 
     //                 v  h  t
+    ASSERT_TRUE(hf.add(1, 0, 0));
     ASSERT_TRUE(hf.add(2, 2, 1));
+    hf.init();
 
-    for (uint64_t h = 0; h < 10; ++h) {
+    for (uint64_t h = 0; h <= 8; ++h) {
       uint8_t v = 1 + !!(h % 8);
-      hf.add(mkblock(v), h);
-      uint8_t expected = threshold == 88 ? 1 : h < 7 ? 1 : 2;
-      ASSERT_EQ(hf.get(h), expected);
+      db.add_block(mkblock(v), 0, 0, 0, crypto::hash());
+      bool ret = hf.add(db.get_block_from_height(h), h);
+      if (h >= 8 && threshold == 87) {
+        ASSERT_FALSE(ret);
+      }
+      else {
+        ASSERT_TRUE(ret);
+        uint8_t expected = threshold == 88 ? 1 : h < 7 ? 1 : 2;
+        ASSERT_EQ(hf.get(h), expected);
+      }
     }
   }
 }
 
 TEST(new_blocks, denied)
 {
-    HardFork hf(1, 1, 1, 4, 50, 10);
+    TestDB db;
+    HardFork hf(db, 1, 1, 1, 4, 50);
 
     //                 v  h  t
+    ASSERT_TRUE(hf.add(1, 0, 0));
     ASSERT_TRUE(hf.add(2, 2, 1));
+    hf.init();
 
     ASSERT_FALSE(hf.add(mkblock(0), 0));
     ASSERT_TRUE(hf.add(mkblock(1), 0));
@@ -322,10 +375,13 @@ TEST(new_blocks, denied)
 
 TEST(new_version, early)
 {
-    HardFork hf(1, 1, 1, 4, 50, 10);
+    TestDB db;
+    HardFork hf(db, 1, 1, 1, 4, 50);
 
     //                 v  h  t
+    ASSERT_TRUE(hf.add(1, 0, 0));
     ASSERT_TRUE(hf.add(2, 4, 1));
+    hf.init();
 
     ASSERT_FALSE(hf.add(mkblock(0), 0));
     ASSERT_TRUE(hf.add(mkblock(2), 0));
@@ -342,12 +398,14 @@ TEST(new_version, early)
 
 TEST(reorganize, changed)
 {
-    HardFork hf(1, 1, 1, 4, 50, 10);
     TestDB db;
+    HardFork hf(db, 1, 1, 1, 4, 50);
 
     //                 v  h  t
+    ASSERT_TRUE(hf.add(1, 0, 0));
     ASSERT_TRUE(hf.add(2, 2, 1));
     ASSERT_TRUE(hf.add(3, 5, 2));
+    hf.init();
 
 #define ADD(v, h, a) \
   do { \
@@ -376,10 +434,10 @@ TEST(reorganize, changed)
 
     // pop a few blocks and check current version goes back down
     db.remove_block();
-    hf.reorganize_from_block_height(&db, 8);
+    hf.reorganize_from_block_height(8);
     ASSERT_EQ(hf.get_current_version(), 3);
     db.remove_block();
-    hf.reorganize_from_block_height(&db, 7);
+    hf.reorganize_from_block_height(7);
     ASSERT_EQ(hf.get_current_version(), 2);
     db.remove_block();
     ASSERT_EQ(hf.get_current_version(), 2);