From 4aeae98a1a080b66fb5b273f77dfc9776928a00c Mon Sep 17 00:00:00 2001
From: silverweed <giacomo.parolini@cern.ch>
Date: Wed, 29 Jan 2025 15:25:51 +0100
Subject: [PATCH] [ntuple] RMiniFile: write StreamerInfo with the correct
 compression

---
 tree/ntuple/v7/inc/ROOT/RMiniFile.hxx   | 5 +++--
 tree/ntuple/v7/src/RMiniFile.cxx        | 8 ++++----
 tree/ntuple/v7/src/RPageStorageFile.cxx | 2 +-
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/tree/ntuple/v7/inc/ROOT/RMiniFile.hxx b/tree/ntuple/v7/inc/ROOT/RMiniFile.hxx
index 7a61e63d74b3a..a2424d0e99fb0 100644
--- a/tree/ntuple/v7/inc/ROOT/RMiniFile.hxx
+++ b/tree/ntuple/v7/inc/ROOT/RMiniFile.hxx
@@ -20,6 +20,7 @@
 #include <ROOT/RNTuple.hxx>
 #include <ROOT/RNTupleSerialize.hxx>
 #include <ROOT/RSpan.hxx>
+#include <Compression.h>
 #include <string_view>
 
 #include <cstdint>
@@ -202,7 +203,7 @@ private:
    /// Write the TList with the RNTuple key
    void WriteTFileKeysList();
    /// Write the compressed streamer info record with the description of the RNTuple class
-   void WriteTFileStreamerInfo();
+   void WriteTFileStreamerInfo(int compression);
    /// Last record in the file
    void WriteTFileFreeList();
    /// For a bare file, which is necessarily written by a C file stream, write file header
@@ -245,7 +246,7 @@ public:
    /// Ensures that the streamer info records passed as argument are written to the file
    void UpdateStreamerInfos(const RNTupleSerializer::StreamerInfoMap_t &streamerInfos);
    /// Writes the RNTuple key to the file so that the header and footer keys can be found
-   void Commit();
+   void Commit(int compression = RCompressionSetting::EDefaults::kUseGeneralPurpose);
 };
 
 } // namespace Internal
diff --git a/tree/ntuple/v7/src/RMiniFile.cxx b/tree/ntuple/v7/src/RMiniFile.cxx
index 4c43dce4c2b39..b11d6498d7571 100644
--- a/tree/ntuple/v7/src/RMiniFile.cxx
+++ b/tree/ntuple/v7/src/RMiniFile.cxx
@@ -1188,7 +1188,7 @@ void ROOT::Experimental::Internal::RNTupleFileWriter::UpdateStreamerInfos(
    fStreamerInfoMap.insert(streamerInfos.cbegin(), streamerInfos.cend());
 }
 
-void ROOT::Experimental::Internal::RNTupleFileWriter::Commit()
+void ROOT::Experimental::Internal::RNTupleFileWriter::Commit(int compression)
 {
    if (fFileProper) {
       // Easy case, the ROOT file header and the RNTuple streaming is taken care of by TFile
@@ -1220,7 +1220,7 @@ void ROOT::Experimental::Internal::RNTupleFileWriter::Commit()
 
    WriteTFileNTupleKey();
    WriteTFileKeysList();
-   WriteTFileStreamerInfo();
+   WriteTFileStreamerInfo(compression);
    WriteTFileFreeList();
 
    // Update header and TFile record
@@ -1365,7 +1365,7 @@ void ROOT::Experimental::Internal::RNTupleFileWriter::WriteBareFileSkeleton(int
    fFileSimple.fKeyOffset = fFileSimple.fFilePos;
 }
 
-void ROOT::Experimental::Internal::RNTupleFileWriter::WriteTFileStreamerInfo()
+void ROOT::Experimental::Internal::RNTupleFileWriter::WriteTFileStreamerInfo(int compression)
 {
    // The streamer info record is a TList of TStreamerInfo object.  We cannot use
    // RNTupleSerializer::SerializeStreamerInfos because that uses TBufferIO::WriteObject.
@@ -1400,7 +1400,7 @@ void ROOT::Experimental::Internal::RNTupleFileWriter::WriteTFileStreamerInfo()
 
    RNTupleCompressor compressor;
    auto zipStreamerInfos = MakeUninitArray<unsigned char>(lenPayload);
-   auto szZipStreamerInfos = compressor.Zip(bufPayload, lenPayload, 1, zipStreamerInfos.get());
+   auto szZipStreamerInfos = compressor.Zip(bufPayload, lenPayload, compression, zipStreamerInfos.get());
 
    fFileSimple.WriteKey(zipStreamerInfos.get(), szZipStreamerInfos, lenPayload,
                         fFileSimple.fControlBlock->fHeader.GetSeekInfo(), RTFHeader::kBEGIN, "TList", "StreamerInfo",
diff --git a/tree/ntuple/v7/src/RPageStorageFile.cxx b/tree/ntuple/v7/src/RPageStorageFile.cxx
index f1acaed0169bd..967a9151b8810 100644
--- a/tree/ntuple/v7/src/RPageStorageFile.cxx
+++ b/tree/ntuple/v7/src/RPageStorageFile.cxx
@@ -245,7 +245,7 @@ void ROOT::Experimental::Internal::RPageSinkFile::CommitDatasetImpl(unsigned cha
    auto szFooterZip = fCompressor->Zip(serializedFooter, length, GetWriteOptions().GetCompression(),
                                        RNTupleCompressor::MakeMemCopyWriter(bufFooterZip.get()));
    fWriter->WriteNTupleFooter(bufFooterZip.get(), szFooterZip, length);
-   fWriter->Commit();
+   fWriter->Commit(GetWriteOptions().GetCompression());
 }
 
 ////////////////////////////////////////////////////////////////////////////////