FIX: Fix potential data corruption in DbnFileStore

Author: threecgreen

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Changelog
 
+## 0.39.1 - TBD
+
+### Bug fixes
+- Fixed potential corrupted data in `DbnFileStore::Replay`
+
 ## 0.39.0 - 2025-07-15
 
 ### Breaking changes

src/dbn_decoder.cpp

@@ -311,7 +311,7 @@ const databento::Record* DbnDecoder::DecodeRecord() {
     }
   }
   current_record_ = Record{BufferRecordHeader()};
-  buffer_.Consume(current_record_.Size());
+  buffer_.ConsumeNoShift(current_record_.Size());
   current_record_ = DbnDecoder::DecodeRecordCompat(
       version_, upgrade_policy_, ts_out_, &compat_buffer_, current_record_);
   return &current_record_;

src/live_blocking.cpp

@@ -190,11 +190,10 @@ const databento::Record* LiveBlocking::NextRecord(
   }
   current_record_ = Record{BufferRecordHeader()};
   const auto bytes_to_consume = current_record_.Size();
+  buffer_.ConsumeNoShift(bytes_to_consume);
   current_record_ =
       DbnDecoder::DecodeRecordCompat(version_, upgrade_policy_, send_ts_out_,
                                      &compat_buffer_, current_record_);
-  // Can't consume til after upgrade as Consume may shift
-  buffer_.Consume(bytes_to_consume);
   return &current_record_;
 }