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// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef COMPONENTS_SQLITE_PROTO_TABLE_MANAGER_H_
#define COMPONENTS_SQLITE_PROTO_TABLE_MANAGER_H_
#include "base/functional/callback.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/ref_counted.h"
#include "base/synchronization/atomic_flag.h"
namespace base {
class Location;
class SequencedTaskRunner;
} // namespace base
namespace sql {
class Database;
}
namespace sqlite_proto {
// Base class encapsulating database operation scheduling and management, scoped
// to a collection of tables (possibly, but not necessarily, all of the
// database's tables).
//
// Refcounted as it is created and destroyed in the main thread (e.g., the UI
// thread in the browser process) but all database related functions need to
// happen in the database sequence. The task runner for this sequence is
// provided by the client to the constructor of this class.
class TableManager : public base::RefCountedThreadSafe<TableManager> {
public:
// Returns a SequencedTaskRunner that is used to run tasks on the DB sequence.
base::SequencedTaskRunner* GetTaskRunner();
TableManager(const TableManager&) = delete;
TableManager& operator=(const TableManager&) = delete;
virtual void ScheduleDBTask(const base::Location& from_here,
base::OnceCallback<void(sql::Database*)> task);
virtual void ScheduleDBTaskWithReply(
const base::Location& from_here,
base::OnceCallback<void(sql::Database*)> task,
base::OnceClosure reply);
virtual void ExecuteDBTaskOnDBSequence(
base::OnceCallback<void(sql::Database*)> task);
protected:
explicit TableManager(
scoped_refptr<base::SequencedTaskRunner> db_task_runner);
virtual ~TableManager();
// DB sequence functions.
//
// Creates tables if nonexistent, first clearing them if necessary, for
// instance if this database has a versioned schema and the version has
// changed since the tables were last written.
virtual void CreateOrClearTablesIfNecessary() = 0;
virtual void LogDatabaseStats() = 0;
void Initialize(sql::Database* db);
void SetCancelled();
bool IsCancelled();
sql::Database* DB();
void ResetDB();
bool CantAccessDatabase();
private:
base::AtomicFlag cancelled_;
friend class base::RefCountedThreadSafe<TableManager>;
scoped_refptr<base::SequencedTaskRunner> db_task_runner_;
raw_ptr<sql::Database> db_;
};
} // namespace sqlite_proto
#endif // COMPONENTS_SQLITE_PROTO_TABLE_MANAGER_H_
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