rocksdb/db/blob/blob_contents.h
Peter Dillinger 206fdea3d9 Change internal headers with duplicate names (#11408)
Summary:
In IDE navigation I find it annoying that there are two statistics.h files (etc.) and often land on the wrong one. Here I migrate several headers to use the blah.h <- blah_impl.h <- blah.cc idiom. Although clang-format wants "blah.h" to be the top include for "blah.cc", I think overall this is an improvement.

No public API changes.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11408

Test Plan: existing tests

Reviewed By: ltamasi

Differential Revision: D45456696

Pulled By: pdillinger

fbshipit-source-id: 809d931253f3272c908cf5facf7e1d32fc507373
2023-05-17 11:27:09 -07:00

60 lines
1.8 KiB
C++

// 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_impl.h"
#include "rocksdb/advanced_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:
BlobContents(CacheAllocationPtr&& allocation, size_t size)
: allocation_(std::move(allocation)), data_(allocation_.get(), 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;
// For TypedCacheInterface
const Slice& ContentSlice() const { return data_; }
static constexpr CacheEntryRole kCacheEntryRole = CacheEntryRole::kBlobValue;
private:
CacheAllocationPtr allocation_;
Slice data_;
};
class BlobContentsCreator : public Cache::CreateContext {
public:
static void Create(std::unique_ptr<BlobContents>* out, size_t* out_charge,
const Slice& contents, MemoryAllocator* alloc) {
auto raw = new BlobContents(AllocateAndCopyBlock(contents, alloc),
contents.size());
out->reset(raw);
if (out_charge) {
*out_charge = raw->ApproximateMemoryUsage();
}
}
};
} // namespace ROCKSDB_NAMESPACE