1 files changed, 56 insertions, 0 deletions
diff --git a/src/rocksdb/db/blob/blob_contents.h b/src/rocksdb/db/blob/blob_contents.h
new file mode 100644
index 000000000..9b7c5b969
--- /dev/null
+++ b/src/rocksdb/db/blob/blob_contents.h
@@ -0,0 +1,56 @@
+//  Copyright (c) Meta Platforms, Inc. and affiliates.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+
+#pragma once
+
+#include <memory>
+
+#include "memory/memory_allocator.h"
+#include "rocksdb/cache.h"
+#include "rocksdb/rocksdb_namespace.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/status.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+// A class representing a single uncompressed value read from a blob file.
+class BlobContents {
+ public:
+  static std::unique_ptr<BlobContents> Create(CacheAllocationPtr&& allocation,
+                                              size_t size);
+
+  BlobContents(const BlobContents&) = delete;
+  BlobContents& operator=(const BlobContents&) = delete;
+
+  BlobContents(BlobContents&&) = default;
+  BlobContents& operator=(BlobContents&&) = default;
+
+  ~BlobContents() = default;
+
+  const Slice& data() const { return data_; }
+  size_t size() const { return data_.size(); }
+
+  size_t ApproximateMemoryUsage() const;
+
+  // Callbacks for secondary cache
+  static size_t SizeCallback(void* obj);
+
+  static Status SaveToCallback(void* from_obj, size_t from_offset,
+                               size_t length, void* out);
+
+  static Cache::CacheItemHelper* GetCacheItemHelper();
+
+  static Status CreateCallback(CacheAllocationPtr&& allocation, const void* buf,
+                               size_t size, void** out_obj, size_t* charge);
+
+ private:
+  BlobContents(CacheAllocationPtr&& allocation, size_t size)
+      : allocation_(std::move(allocation)), data_(allocation_.get(), size) {}
+
+  CacheAllocationPtr allocation_;
+  Slice data_;
+};
+
+}  // namespace ROCKSDB_NAMESPACE