wallet & PoS: don't try to mine a PoS block if the current sequence factor is too high

src/currency_core/blockchain_storage.cpp

@@ -70,15 +70,6 @@ using namespace currency;
 
 #define TARGETDATA_CACHE_SIZE                          DIFFICULTY_WINDOW + 10
 
-#ifndef TESTNET
-#define BLOCKCHAIN_HEIGHT_FOR_POS_STRICT_SEQUENCE_LIMITATION          57000
-#else
-#define BLOCKCHAIN_HEIGHT_FOR_POS_STRICT_SEQUENCE_LIMITATION          18000
-#endif
-#define BLOCK_POS_STRICT_SEQUENCE_LIMIT                               20
-
-
-
 DISABLE_VS_WARNINGS(4267)
 
 namespace 

src/currency_core/currency_config.h

@@ -154,6 +154,13 @@
 #define POS_WALLET_MINING_SCAN_INTERVAL                 POS_SCAN_STEP  //seconds
 #define POS_MINIMUM_COINSTAKE_AGE                       10 // blocks count
 
+#ifndef TESTNET
+#  define BLOCKCHAIN_HEIGHT_FOR_POS_STRICT_SEQUENCE_LIMITATION 57000
+#else
+#  define BLOCKCHAIN_HEIGHT_FOR_POS_STRICT_SEQUENCE_LIMITATION 18000
+#endif
+#define BLOCK_POS_STRICT_SEQUENCE_LIMIT                 20
+
 
 #define WALLET_FILE_SIGNATURE_OLD                       0x1111012101101011LL  // Bender's nightmare
 #define WALLET_FILE_SIGNATURE_V2                        0x1111011201101011LL  // another Bender's nightmare

src/rpc/core_rpc_server.cpp

@@ -541,6 +541,12 @@ namespace currency
       return true;
     }
 
+    res.pos_sequence_factor_is_good = true;
+    uint64_t new_block_expected_height = m_core.get_blockchain_storage().get_top_block_height() + 1;
+    size_t new_block_expected_sequence_factor = m_core.get_blockchain_storage().get_current_sequence_factor(true) + 1;
+    if (new_block_expected_height > BLOCKCHAIN_HEIGHT_FOR_POS_STRICT_SEQUENCE_LIMITATION && new_block_expected_sequence_factor > BLOCK_POS_STRICT_SEQUENCE_LIMIT)
+      res.pos_sequence_factor_is_good = false;
+
     res.pos_basic_difficulty = m_core.get_blockchain_storage().get_next_diff_conditional(true).convert_to<std::string>();
     m_core.get_blockchain_storage().build_stake_modifier(res.sm, blockchain_storage::alt_chain_type(), 0, &res.last_block_hash);// , &res.height);
     

src/rpc/core_rpc_server_commands_defs.h

@@ -1154,12 +1154,14 @@ namespace currency
       std::string status;
       crypto::hash last_block_hash;
       bool pos_mining_allowed;
+      bool pos_sequence_factor_is_good;
 
       BEGIN_KV_SERIALIZE_MAP()
         KV_SERIALIZE_VAL_POD_AS_BLOB(sm)
         KV_SERIALIZE(pos_basic_difficulty)
         KV_SERIALIZE(starter_timestamp)
         KV_SERIALIZE(pos_mining_allowed)
+        KV_SERIALIZE(pos_sequence_factor_is_good)
         KV_SERIALIZE(status)
         KV_SERIALIZE_VAL_POD_AS_BLOB(last_block_hash)
       END_KV_SERIALIZE_MAP()

src/wallet/wallet2.cpp

@@ -4253,9 +4253,10 @@ bool wallet2::fill_mining_context(mining_context& ctx)
   ctx = mining_context{};
   ctx.init(wide_difficulty_type(pos_details_resp.pos_basic_difficulty), pos_details_resp.sm, is_in_hardfork_zone(ZANO_HARDFORK_04_ZARCANUM));
 
-  ctx.last_block_hash = pos_details_resp.last_block_hash;
-  ctx.is_pos_allowed = pos_details_resp.pos_mining_allowed;
-  ctx.starter_timestamp = pos_details_resp.starter_timestamp;
+  ctx.last_block_hash             = pos_details_resp.last_block_hash;
+  ctx.is_pos_allowed              = pos_details_resp.pos_mining_allowed;
+  ctx.is_pos_sequence_factor_good = pos_details_resp.pos_sequence_factor_is_good;
+  ctx.starter_timestamp           = pos_details_resp.starter_timestamp;
   ctx.status = API_RETURN_CODE_NOT_FOUND;
   return true;
 }
@@ -4271,12 +4272,19 @@ bool wallet2::try_mint_pos(const currency::account_public_address& miner_address
   mining_context ctx = AUTO_VAL_INIT(ctx);
   WLT_LOG_L1("Starting PoS mining iteration");
   fill_mining_context(ctx);
+  
   if (!ctx.is_pos_allowed)
   {
     WLT_LOG_YELLOW("POS MINING NOT ALLOWED YET", LOG_LEVEL_0);
     return true;
   }
 
+  if (!ctx.is_pos_sequence_factor_good)
+  {
+    WLT_LOG_YELLOW("PoS sequence factor is too big, waiting for a PoW block...", LOG_LEVEL_0);
+    return true;
+  }
+
   std::atomic<bool> stop(false);
   scan_pos(ctx, stop, [this](){
     size_t blocks_fetched;

src/wallet/wallet2.h

@@ -469,6 +469,7 @@ namespace tools
       std::string   status;
 
       bool          is_pos_allowed = false;
+      bool          is_pos_sequence_factor_good = false;
 
       uint64_t      index = 0; // index in m_transfers 
       uint64_t      stake_unlock_time = 0;

tests/core_tests/chaingen.cpp

@@ -430,6 +430,8 @@ bool test_generator::build_wallets(const blockchain_vector& blockchain,
         return true;
       }
 
+      rsp.pos_sequence_factor_is_good = true;
+
       build_stake_modifier(rsp.sm, m_blockchain);
     
       uint64_t median_timestamp = get_timestamps_median(m_blockchain);