From 2a292786a6dd6156be724363708ddd97b9e0ae38 Mon Sep 17 00:00:00 2001
From: edtubbs <ectubbs@gmail.com>
Date: Thu, 16 May 2024 13:21:59 -0500
Subject: [PATCH] headersdb_file: added chainwork to database record

headersdb_file: added chainwork to load and write
headersdb_file: added chainwork check on write
headersdb_file: updated current version for chainwork
---
 src/headersdb_file.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/src/headersdb_file.c b/src/headersdb_file.c
index 993ae474c..7af06f934 100644
--- a/src/headersdb_file.c
+++ b/src/headersdb_file.c
@@ -37,7 +37,7 @@
 #include <dogecoin/validation.h>
 
 static const unsigned char file_hdr_magic[4] = {0xA8, 0xF0, 0x11, 0xC5}; /* header magic */
-static const uint32_t current_version = 2;
+static const uint32_t current_version = 3; /* 3: added chainwork */
 
 /**
  * "Compare two block headers by their hashes."
@@ -217,7 +217,7 @@ dogecoin_bool dogecoin_headers_db_load(dogecoin_headers_db* db, const char *file
                 fflush(stdout);
             }
 
-            uint8_t buf_all[32+4+80];
+            uint8_t buf_all[32+4+32+80];
             if (fread(buf_all, sizeof(buf_all), 1, db->headers_tree_file) == 1) {
                 struct const_buffer cbuf_all = {buf_all, sizeof(buf_all)};
 
@@ -225,8 +225,10 @@ dogecoin_bool dogecoin_headers_db_load(dogecoin_headers_db* db, const char *file
 
                 uint256 hash;
                 uint32_t height;
+                uint256 chainwork;
                 deser_u256(hash, &cbuf_all);
                 deser_u32(&height, &cbuf_all);
+                deser_u256(chainwork, &cbuf_all);
                 dogecoin_bool connected;
                 if (firstblock)
                 {
@@ -253,6 +255,7 @@ dogecoin_bool dogecoin_headers_db_load(dogecoin_headers_db* db, const char *file
                         connected_headers_count++;
                     }
                 }
+                memcpy(db->chaintip->chainwork, chainwork, sizeof(uint256));
             }
         }
     }
@@ -269,9 +272,10 @@ dogecoin_bool dogecoin_headers_db_load(dogecoin_headers_db* db, const char *file
  * @return Nothing.
  */
 dogecoin_bool dogecoin_headers_db_write(dogecoin_headers_db* db, dogecoin_blockindex *blockindex) {
-    cstring *rec = cstr_new_sz(100);
+    cstring *rec = cstr_new_sz(148); // hash + height + chainwork + header
     ser_u256(rec, blockindex->hash);
     ser_u32(rec, blockindex->height);
+    ser_u256(rec, blockindex->chainwork);
     dogecoin_block_header_serialize(rec, &blockindex->header);
     size_t res = fwrite(rec->str, rec->len, 1, db->headers_tree_file);
     dogecoin_file_commit(db->headers_tree_file);
@@ -420,11 +424,7 @@ dogecoin_blockindex * dogecoin_headers_db_connect_hdr(dogecoin_headers_db* db, s
             db->chaintip = blockindex;
         }
 
-        // Free the dynamically allocated memory
-        dogecoin_free(chaintip_chainwork);
-        dogecoin_free(added_chainwork);
-
-        if (!load_process && db->read_write_file)
+        if (!load_process && db->read_write_file && arith_uint256_greater_than(added_chainwork, chaintip_chainwork))
         {
             if (!dogecoin_headers_db_write(db, blockindex)) {
                 fprintf(stderr, "Error writing blockheader to database\n");
@@ -434,6 +434,10 @@ dogecoin_blockindex * dogecoin_headers_db_connect_hdr(dogecoin_headers_db* db, s
             dogecoin_btree_tsearch(blockindex, &db->tree_root, dogecoin_header_compare);
         }
 
+        // Free the dynamically allocated memory
+        dogecoin_free(chaintip_chainwork);
+        dogecoin_free(added_chainwork);
+
         if (db->max_hdr_in_mem > 0) {
             // de-allocate no longer required headers
             // keep them only on-disk