YugabyteDB (2.13.0.0-b42, bfc6a6643e7399ac8a0e81d06a3ee6d6571b33ab)

// Copyright (c) 2015, Red Hat, Inc.  All rights reserved.

// This source code is licensed under the BSD-style license found in the

// LICENSE file in the root directory of this source tree. An additional grant

// of patent rights can be found in the PATENTS file in the same directory.

// Copyright (c) 2011 The LevelDB Authors. All rights reserved.

// Use of this source code is governed by a BSD-style license that can be

// found in the LICENSE file. See the AUTHORS file for names of contributors.

//

// The following only applies to changes made to this file as part of YugaByte development.

//

// Portions Copyright (c) YugaByte, Inc.

//

// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except

// in compliance with the License.  You may obtain a copy of the License at

//

// http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software distributed under the License

// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express

// or implied.  See the License for the specific language governing permissions and limitations

// under the License.

//

// MirrorEnv is an Env implementation that mirrors all file-related

// operations to two backing Env's (provided at construction time).

// Writes are mirrored.  For read operations, we do the read from both

// backends and assert that the results match.

//

// This is useful when implementing a new Env and ensuring that the

// semantics and behavior are correct (in that they match that of an

// existing, stable Env, like the default POSIX one).

#ifndef YB_ROCKSDB_UTILITIES_ENV_MIRROR_H

#define YB_ROCKSDB_UTILITIES_ENV_MIRROR_H

#ifndef ROCKSDB_LITE

#include <iostream>

#include <algorithm>

#include <vector>

#include "yb/rocksdb/env.h"

namespace rocksdb {

class SequentialFileMirror;

class RandomAccessFileMirror;

class WritableFileMirror;

class EnvMirror : public EnvWrapper {

  Env* a_, *b_;

 public:

  EnvMirror(Env* a, Env* b) : EnvWrapper(a), a_(a), b_(b) {}

  Status NewSequentialFile(const std::string& f, unique_ptr<SequentialFile>* r,

                           const EnvOptions& options) override;

  Status NewRandomAccessFile(const std::string& f,

                             unique_ptr<RandomAccessFile>* r,

                             const EnvOptions& options) override;

  Status NewWritableFile(const std::string& f, unique_ptr<WritableFile>* r,

                         const EnvOptions& options) override;

  Status ReuseWritableFile(const std::string& fname,

                           const std::string& old_fname,

                           unique_ptr<WritableFile>* r,

                           const EnvOptions& options) override;

  Status NewDirectory(const std::string& name,

                      unique_ptr<Directory>* result) override;

  Status FileExists(const std::string& f) override;

  Status GetChildren(const std::string& dir,

                     std::vector<std::string>* r) override;

  Status DeleteFile(const std::string& f) override;

  Status CreateDir(const std::string& d) override;

  Status CreateDirIfMissing(const std::string& d) override;

  Status DeleteDir(const std::string& d) override;

  Status GetFileSize(const std::string& f, uint64_t* s) override;

  Status GetFileModificationTime(const std::string& fname,

                                 uint64_t* file_mtime) override;

  Status RenameFile(const std::string& s, const std::string& t) override;

  Status LinkFile(const std::string& s, const std::string& t) override;

  class FileLockMirror : public FileLock {

   public:

    FileLock* a_, *b_;

    FileLockMirror(FileLock* a, FileLock* b) : a_(a), b_(b) {}

  };

  Status LockFile(const std::string& f, FileLock** l) override;

  Status UnlockFile(FileLock* l) override;

};

}  // namespace rocksdb

#endif  // ROCKSDB_LITE

#endif  // YB_ROCKSDB_UTILITIES_ENV_MIRROR_H