From 14a7f266425d9bd3fb0b993279440336391c8ed7 Mon Sep 17 00:00:00 2001
From: Yanqin Jin <yanqin@fb.com>
Date: Fri, 15 Apr 2022 18:24:40 -0700
Subject: [PATCH] Add GetSharedSnapshot() to Transaction

---
 include/rocksdb/utilities/transaction.h   | 4 ++++
 utilities/transactions/transaction_base.h | 4 ++++
 2 files changed, 8 insertions(+)

diff --git a/include/rocksdb/utilities/transaction.h b/include/rocksdb/utilities/transaction.h
index ecb797506..8e17e1d8b 100644
--- a/include/rocksdb/utilities/transaction.h
+++ b/include/rocksdb/utilities/transaction.h
@@ -193,6 +193,10 @@ class Transaction {
   // is called, or the Transaction is deleted.
   virtual const Snapshot* GetSnapshot() const = 0;
 
+  // Returns the Snapshot created by the last call to SetSnapshot().
+  // The returned snapshot can outlive the transaction.
+  virtual std::shared_ptr<const Snapshot> GetSharedSnapshot() const = 0;
+
   // Clears the current snapshot (i.e. no snapshot will be 'set')
   //
   // This removes any snapshot that currently exists or is set to be created
diff --git a/utilities/transactions/transaction_base.h b/utilities/transactions/transaction_base.h
index e4da8d44b..7fc51f87a 100644
--- a/utilities/transactions/transaction_base.h
+++ b/utilities/transactions/transaction_base.h
@@ -206,6 +206,10 @@ class TransactionBaseImpl : public Transaction {
     return snapshot_.get();
   }
 
+  std::shared_ptr<const Snapshot> GetSharedSnapshot() const override {
+    return snapshot_;
+  }
+
   virtual void SetSnapshot() override;
   void SetSnapshotOnNextOperation(
       std::shared_ptr<TransactionNotifier> notifier = nullptr) override;