From 58a23f5f7bbe316e5d172d735cae8ea38e1e72da Mon Sep 17 00:00:00 2001
From: obdev <obdev@oceanbase.com>
Date: Fri, 16 Dec 2022 04:07:57 +0000
Subject: [PATCH] [bugfix] fix  compatibility of log_block_header

---
 src/logservice/palf/log_block_header.cpp |  2 +-
 src/share/scn.cpp                        | 12 +++++++++++-
 src/share/scn.h                          |  2 ++
 3 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/logservice/palf/log_block_header.cpp b/src/logservice/palf/log_block_header.cpp
index 7a5ee70af..d0bc1a345 100644
--- a/src/logservice/palf/log_block_header.cpp
+++ b/src/logservice/palf/log_block_header.cpp
@@ -149,7 +149,7 @@ DEFINE_DESERIALIZE(LogBlockHeader)
              || OB_FAIL(serialization::decode_i32(buf, data_len, new_pos, &flag_))
              || OB_FAIL(min_lsn_.deserialize(buf, data_len, new_pos))
              || OB_FAIL(min_scn_.fixed_deserialize(buf, data_len, new_pos))
-             || OB_FAIL(max_scn_.fixed_deserialize(buf, data_len, new_pos))
+             || OB_FAIL(max_scn_.fixed_deserialize_without_transform(buf, data_len, new_pos))
              || OB_FAIL(serialization::decode_i64(buf, data_len, new_pos, reinterpret_cast<int64_t*>(&curr_block_id_)))
              || OB_FAIL(serialization::decode_i64(buf, data_len, new_pos, &palf_id_))
              || OB_FAIL(serialization::decode_i64(buf, data_len, new_pos, &checksum_))) {
diff --git a/src/share/scn.cpp b/src/share/scn.cpp
index cd26ddaba..582967a36 100644
--- a/src/share/scn.cpp
+++ b/src/share/scn.cpp
@@ -476,7 +476,7 @@ int SCN::to_yson(char *buf, const int64_t buf_len, int64_t &pos) const
   return oceanbase::yson::databuff_encode_elements(buf, buf_len, pos, OB_ID(scn_val), val_);
 }
 
-int SCN::fixed_deserialize(const char* buf, const int64_t data_len, int64_t& pos)
+int SCN::fixed_deserialize_without_transform(const char* buf, const int64_t data_len, int64_t& pos)
 {
   int ret = OB_SUCCESS;
   int64_t new_pos = pos;
@@ -488,6 +488,16 @@ int SCN::fixed_deserialize(const char* buf, const int64_t data_len, int64_t& pos
     PALF_LOG(WARN, "failed to decode val_", K(buf), K(data_len), K(new_pos), K(ret));
   } else {
     pos = new_pos;
+  }
+  return ret;
+}
+
+int SCN::fixed_deserialize(const char* buf, const int64_t data_len, int64_t& pos)
+{
+  int ret = OB_SUCCESS;
+  if (OB_FAIL(fixed_deserialize_without_transform(buf, data_len, pos))) {
+    PALF_LOG(WARN, "failed to fixed_deserialize_without_transform", K(buf), K(data_len), K(pos), K(ret));
+  } else {
     (void)transform_max_();
   }
   return ret;
diff --git a/src/share/scn.h b/src/share/scn.h
index 396321d1a..8ad912f7b 100644
--- a/src/share/scn.h
+++ b/src/share/scn.h
@@ -109,6 +109,8 @@ public:
 
   //fixed length serialization
   int fixed_serialize(char* buf, const int64_t buf_len, int64_t& pos) const;
+  //used for checksum with old value of INT64_MAX, if transforming max value, checksum will change;
+  int fixed_deserialize_without_transform(const char* buf, const int64_t data_len, int64_t& pos);
   int fixed_deserialize(const char* buf, const int64_t data_len, int64_t& pos);
   int64_t get_fixed_serialize_size(void) const;