Added ability to read chechpoint hashes from json file in data folder

src/cryptonote_core/checkpoints.cpp

@@ -93,4 +93,13 @@ namespace cryptonote
     uint64_t checkpoint_height = it->first;
     return checkpoint_height < block_height;
   }
+  uint64_t checkpoints::get_max_height()
+  {
+    std::map< uint64_t, crypto::hash >::const_iterator highest = 
+        std::max_element( m_points.begin(), m_points.end(),
+                         ( boost::bind(&std::map< uint64_t, crypto::hash >::value_type::first, _1) < 
+                           boost::bind(&std::map< uint64_t, crypto::hash >::value_type::first, _2 ) ) );
+    return highest->first;
+  }
+
 }

src/cryptonote_core/checkpoints.h

@@ -44,6 +44,7 @@ namespace cryptonote
     bool check_block(uint64_t height, const crypto::hash& h) const;
     bool check_block(uint64_t height, const crypto::hash& h, bool& is_a_checkpoint) const;
     bool is_alternative_block_allowed(uint64_t blockchain_height, uint64_t block_height) const;
+    uint64_t get_max_height();
 
   private:
     std::map<uint64_t, crypto::hash> m_points;

src/cryptonote_core/checkpoints_create.h

@@ -34,6 +34,24 @@
 #include "misc_log_ex.h"
 
 #define ADD_CHECKPOINT(h, hash)  CHECK_AND_ASSERT(checkpoints.add_checkpoint(h,  hash), false);
+#define JSON_HASH_FILE_NAME "checkpoints.json"
+
+struct t_hashline 
+{
+	uint64_t height;
+	std::string hash;
+      BEGIN_KV_SERIALIZE_MAP()
+        KV_SERIALIZE(height)
+        KV_SERIALIZE(hash)
+      END_KV_SERIALIZE_MAP()
+};
+
+struct t_hash_json {
+ 	std::vector<t_hashline> hashlines;
+      BEGIN_KV_SERIALIZE_MAP()
+        KV_SERIALIZE(hashlines)
+      END_KV_SERIALIZE_MAP()
+};
 
 namespace cryptonote {
   inline bool create_checkpoints(cryptonote::checkpoints& checkpoints)
@@ -59,4 +77,36 @@ namespace cryptonote {
 
     return true;
   }
+
+  inline bool load_checkpoins_from_json(cryptonote::checkpoints& checkpoints, std::string json_hashfile_fullpath)
+  {
+    boost::system::error_code errcode;
+    if (! (boost::filesystem::exists(json_hashfile_fullpath, errcode)))
+    {
+      LOG_PRINT_L0("Blockchain checkpoints file not found");
+      return true;
+    }
+
+    LOG_PRINT_L0("Adding checkpoints from blockchain hashfile");
+
+    uint64_t prev_max_height = checkpoints.get_max_height();
+    LOG_PRINT_L0("Hard-coded max checkpoint height is " << prev_max_height);
+    t_hash_json hashes;
+    epee::serialization::load_t_from_json_file(hashes, json_hashfile_fullpath);
+    for (std::vector<t_hashline>::const_iterator it = hashes.hashlines.begin(); it != hashes.hashlines.end(); )
+    {
+	uint64_t height;
+	height = it->height;
+        if (height <= prev_max_height) {
+          LOG_PRINT_L0("ignoring checkpoint height " << height);
+        } else {
+          std::string blockhash = it->hash;
+          LOG_PRINT_L0("Adding checkpoint height " << height << ", hash=" << blockhash);
+	  ADD_CHECKPOINT(height, blockhash);
+        }
+	++it;
+    }
+
+    return true;
+  }
 }

src/daemon/daemon.cpp

@@ -44,6 +44,7 @@ using namespace epee;
 #include "p2p/net_node.h"
 #include "cryptonote_config.h"
 #include "cryptonote_core/checkpoints_create.h"
+#include "cryptonote_core/checkpoints.h"
 #include "cryptonote_core/cryptonote_core.h"
 #include "rpc/core_rpc_server.h"
 #include "cryptonote_protocol/cryptonote_protocol_handler.h"
@@ -203,6 +204,10 @@ int main(int argc, char* argv[])
   cryptonote::checkpoints checkpoints;
   res = cryptonote::create_checkpoints(checkpoints);
   CHECK_AND_ASSERT_MES(res, 1, "Failed to initialize checkpoints");
+  boost::filesystem::path json(JSON_HASH_FILE_NAME);
+  boost::filesystem::path checkpoint_json_hashfile_fullpath = data_dir / json;
+  res = cryptonote::load_checkpoins_from_json(checkpoints, checkpoint_json_hashfile_fullpath.string().c_str());
+  CHECK_AND_ASSERT_MES(res, 1, "Failed to load initial checkpoints");
 
   //create objects and link them
   cryptonote::core ccore(NULL);