alt_chain_info can now give more info about a particular alt chain

4 files changed, 31 insertions, 10 deletions

diff --git a/src/daemon/command_parser_executor.cpp b/src/daemon/command_parser_executor.cpp
index 34d9fb4c8..36e040ab5 100644
--- a/src/daemon/command_parser_executor.cpp
+++ b/src/daemon/command_parser_executor.cpp
@@ -599,13 +599,13 @@ bool t_command_parser_executor::print_coinbase_tx_sum(const std::vector<std::str
 
 bool t_command_parser_executor::alt_chain_info(const std::vector<std::string>& args)
 {
-  if(args.size())
+  if(args.size() > 1)
   {
-    std::cout << "No parameters allowed" << std::endl;
+    std::cout << "usage: alt_chain_info [block_hash]" << std::endl;
     return false;
   }
 
-  return m_executor.alt_chain_info();
+  return m_executor.alt_chain_info(args.size() == 1 ? args[0] : "");
 }
 
 bool t_command_parser_executor::print_blockchain_dynamic_stats(const std::vector<std::string>& args)
diff --git a/src/daemon/command_server.cpp b/src/daemon/command_server.cpp
index 144603597..35504f2c9 100644
--- a/src/daemon/command_server.cpp
+++ b/src/daemon/command_server.cpp
@@ -255,6 +255,7 @@ t_command_server::t_command_server(
     m_command_lookup.set_handler(
       "alt_chain_info"
     , std::bind(&t_command_parser_executor::alt_chain_info, &m_parser, p::_1)
+    , "alt_chain_info [blockhash]"
     , "Print the information about alternative chains."
     );
     m_command_lookup.set_handler(
diff --git a/src/daemon/rpc_command_executor.cpp b/src/daemon/rpc_command_executor.cpp
index 487853441..0b5b05d3d 100644
--- a/src/daemon/rpc_command_executor.cpp
+++ b/src/daemon/rpc_command_executor.cpp
@@ -1628,7 +1628,7 @@ 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()
+bool t_rpc_command_executor::alt_chain_info(const std::string &tip)
 {
   cryptonote::COMMAND_RPC_GET_INFO::request ireq;
   cryptonote::COMMAND_RPC_GET_INFO::response ires;
@@ -1663,12 +1663,32 @@ bool t_rpc_command_executor::alt_chain_info()
     }
   }
 
-  tools::msg_writer() << boost::lexical_cast<std::string>(res.chains.size()) << " alternate chains found:";
-  for (const auto &chain: res.chains)
+  if (tip.empty())
   {
-    uint64_t start_height = (chain.height - chain.length + 1);
-    tools::msg_writer() << chain.length << " blocks long, from height " << start_height << " (" << (ires.height - start_height - 1)
-        << " deep), diff " << chain.difficulty << ": " << chain.block_hash;
+    tools::msg_writer() << boost::lexical_cast<std::string>(res.chains.size()) << " alternate chains found:";
+    for (const auto &chain: res.chains)
+    {
+      uint64_t start_height = (chain.height - chain.length + 1);
+      tools::msg_writer() << chain.length << " blocks long, from height " << start_height << " (" << (ires.height - start_height - 1)
+          << " deep), diff " << chain.difficulty << ": " << chain.block_hash;
+    }
+  }
+  else
+  {
+    const auto i = std::find_if(res.chains.begin(), res.chains.end(), [&tip](cryptonote::COMMAND_RPC_GET_ALTERNATE_CHAINS::chain_info &info){ return info.block_hash == tip; });
+    if (i != res.chains.end())
+    {
+      const auto &chain = *i;
+      tools::success_msg_writer() << "Found alternate chain with tip " << tip;
+      uint64_t start_height = (chain.height - chain.length + 1);
+      tools::msg_writer() << chain.length << " blocks long, from height " << start_height << " (" << (ires.height - start_height - 1)
+          << " deep), diff " << chain.difficulty << ":";
+      for (const std::string &block_id: chain.block_hashes)
+        tools::msg_writer() << "  " << block_id;
+      tools::msg_writer() << "Chain parent on main chain: " << chain.main_chain_parent_block;
+    }
+    else
+      tools::fail_msg_writer() << "Block hash " << tip << " is not the tip of any known alternate chain";
   }
   return true;
 }
diff --git a/src/daemon/rpc_command_executor.h b/src/daemon/rpc_command_executor.h
index 46168c93b..9e6010c5b 100644
--- a/src/daemon/rpc_command_executor.h
+++ b/src/daemon/rpc_command_executor.h
@@ -143,7 +143,7 @@ public:
 
   bool print_coinbase_tx_sum(uint64_t height, uint64_t count);
 
-  bool alt_chain_info();
+  bool alt_chain_info(const std::string &tip);
 
   bool print_blockchain_dynamic_stats(uint64_t nblocks);