From 1a9c1681ebf4d460f007b76fdb0e100822adb11e Mon Sep 17 00:00:00 2001
From: taiyang-li <654010905@qq.com>
Date: Wed, 16 Feb 2022 12:35:40 +0800
Subject: [PATCH] add interface to get raw orc reader from adapters

---
 cpp/src/arrow/adapters/orc/adapter.cc | 9 +++++++++
 cpp/src/arrow/adapters/orc/adapter.h  | 3 +++
 2 files changed, 12 insertions(+)

diff --git a/cpp/src/arrow/adapters/orc/adapter.cc b/cpp/src/arrow/adapters/orc/adapter.cc
index 9bb4abfd0f05..2ce4356dffa4 100644
--- a/cpp/src/arrow/adapters/orc/adapter.cc
+++ b/cpp/src/arrow/adapters/orc/adapter.cc
@@ -199,6 +199,11 @@ class ORCFileReader::Impl {
     return Init();
   }
 
+  virtual liborc::Reader* GetRawORCReader() {
+    return reader_.get();
+  }
+
+
   Status Init() {
     int64_t nstripes = reader_->getNumberOfStripes();
     stripes_.resize(nstripes);
@@ -439,6 +444,10 @@ class ORCFileReader::Impl {
     return Status::OK();
   }
 
+  liborc::Reader* ORCFileReader::GetRawORCReader() {
+    return impl_->GetRawORCReader();
+  }
+
   Status NextStripeReader(int64_t batch_size, std::shared_ptr<RecordBatchReader>* out) {
     return NextStripeReader(batch_size, {}, out);
   }
diff --git a/cpp/src/arrow/adapters/orc/adapter.h b/cpp/src/arrow/adapters/orc/adapter.h
index e053eab435b2..a38683776bbe 100644
--- a/cpp/src/arrow/adapters/orc/adapter.h
+++ b/cpp/src/arrow/adapters/orc/adapter.h
@@ -49,6 +49,9 @@ class ARROW_EXPORT ORCFileReader {
   ARROW_DEPRECATED("Deprecated in 6.0.0. Use Result-returning overload instead.")
   static Status Open(const std::shared_ptr<io::RandomAccessFile>& file, MemoryPool* pool,
                      std::unique_ptr<ORCFileReader>* reader);
+ 
+  /// \brief Get ORC reader from inside.
+  liborc::Reader* GetRawORCReader();
 
   /// \brief Creates a new ORC reader
   ///