rpc: new function and RPC to get alternative chain info

src/daemon/command_parser_executor.cpp

@@ -482,4 +482,15 @@ bool t_command_parser_executor::print_coinbase_tx_sum(const std::vector<std::str
   return m_executor.print_coinbase_tx_sum(height, count);
 }
 
+bool t_command_parser_executor::alt_chain_info(const std::vector<std::string>& args)
+{
+  if(args.size())
+  {
+    std::cout << "No parameters allowed" << std::endl;
+    return false;
+  }
+
+  return m_executor.alt_chain_info();
+}
+
 } // namespace daemonize

src/daemon/command_parser_executor.h

@@ -119,6 +119,8 @@ public:
   bool output_histogram(const std::vector<std::string>& args);
 
   bool print_coinbase_tx_sum(const std::vector<std::string>& args);
+
+  bool alt_chain_info(const std::vector<std::string>& args);
 };
 
 } // namespace daemonize

src/daemon/command_server.cpp

@@ -225,6 +225,11 @@ t_command_server::t_command_server(
     , std::bind(&t_command_parser_executor::print_coinbase_tx_sum, &m_parser, p::_1)
     , "Print sum of coinbase transactions (start height, block count)"
     );
+    m_command_lookup.set_handler(
+      "alt_chain_info"
+    , std::bind(&t_command_parser_executor::alt_chain_info, &m_parser, p::_1)
+    , "Print information about alternative chains"
+    );
 }
 
 bool t_command_server::process_command_str(const std::string& cmd)

src/daemon/rpc_command_executor.cpp

@@ -1367,5 +1367,38 @@ bool t_rpc_command_executor::print_coinbase_tx_sum(uint64_t height, uint64_t cou
   return true;
 }
 
+bool t_rpc_command_executor::alt_chain_info()
+{
+  cryptonote::COMMAND_RPC_GET_ALTERNATE_CHAINS::request req;
+  cryptonote::COMMAND_RPC_GET_ALTERNATE_CHAINS::response res;
+  epee::json_rpc::error error_resp;
+
+  std::string fail_message = "Unsuccessful";
+
+  if (m_is_rpc)
+  {
+    if (!m_rpc_client->json_rpc_request(req, res, "get_alternate_chains", fail_message.c_str()))
+    {
+      return true;
+    }
+  }
+  else
+  {
+    if (!m_rpc_server->on_get_alternate_chains(req, res, error_resp))
+    {
+      tools::fail_msg_writer() << fail_message.c_str();
+      return true;
+    }
+  }
+
+  tools::msg_writer() << boost::lexical_cast<std::string>(res.chains.size()) << " alternate chains found:";
+  for (const auto chain: res.chains)
+  {
+    tools::msg_writer() << chain.length << " blocks long, branching at height " << (chain.height - chain.length + 1)
+        << ", difficulty " << chain.difficulty << ": " << chain.block_hash;
+  }
+  return true;
+}
+
 
 }// namespace daemonize

src/daemon/rpc_command_executor.h

@@ -137,6 +137,8 @@ public:
   bool output_histogram(uint64_t min_count, uint64_t max_count);
 
   bool print_coinbase_tx_sum(uint64_t height, uint64_t count);
+
+  bool alt_chain_info();
 };
 
 } // namespace daemonize