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Diffstat (limited to 'src/rocksdb/db/blob/blob_contents.h')
-rw-r--r-- | src/rocksdb/db/blob/blob_contents.h | 56 |
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 |