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// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CONTENT_BROWSER_LEVELDB_WRAPPER_IMPL_H_
#define CONTENT_BROWSER_LEVELDB_WRAPPER_IMPL_H_
#include "base/callback.h"
#include "base/macros.h"
#include "content/common/leveldb_wrapper.mojom.h"
#include "mojo/public/cpp/bindings/binding_set.h"
#include "mojo/public/cpp/bindings/interface_ptr_set.h"
namespace content {
// This is a wrapper around a leveldb::LevelDBDatabase. It adds a couple of
// features:
// 1) Adds the given prefix, if any, to all keys. This allows the sharing of one
// database across many, possibly untrusted, consumers and ensuring that they
// can't access each other's values.
// 2) Enforces a max_size constraint.
// 3) Informs an observer when the given prefix' values are modified.
// 4) Throttles requests to avoid overwhelming the disk.
class LevelDBWrapperImpl : public mojom::LevelDBWrapper {
public:
// |no_bindings_callback| will be called when this object has no more
// bindings.
LevelDBWrapperImpl(leveldb::LevelDBDatabase* database,
const std::string& prefix,
size_t max_size,
const base::Closure& no_bindings_callback);
~LevelDBWrapperImpl() override;
void Bind(mojom::LevelDBWrapperRequest request);
void AddObserver(mojom::LevelDBObserverPtr observer);
private:
// LevelDBWrapperImpl:
void Put(mojo::Array<uint8_t> key,
mojo::Array<uint8_t> value,
const mojo::String& source,
const PutCallback& callback) override;
void Delete(mojo::Array<uint8_t> key,
const mojo::String& source,
const DeleteCallback& callback) override;
void DeleteAll(const mojo::String& source,
const DeleteAllCallback& callback) override;
void Get(mojo::Array<uint8_t> key, const GetCallback& callback) override;
void GetAll(const mojo::String& source,
const GetAllCallback& callback) override;
void OnConnectionError();
std::string prefix_;
mojo::BindingSet<mojom::LevelDBWrapper> bindings_;
mojo::InterfacePtrSet<mojom::LevelDBObserver> observers_;
base::Closure no_bindings_callback_;
leveldb::LevelDBDatabase* database_;
std::map<mojo::Array<uint8_t>, mojo::Array<uint8_t>> map_;
size_t bytes_used_;
size_t max_size_;
DISALLOW_COPY_AND_ASSIGN(LevelDBWrapperImpl);
};
} // namespace content
#endif // CONTENT_BROWSER_LEVELDB_WRAPPER_IMPL_H_
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