Function NewRandomAccessFile

src/leveldb/include/leveldb/env.h:328–331

    return target_->NewSequentialFile(f, r);
  }
  Status NewRandomAccessFile(const std::string& f,
                             RandomAccessFile** r) override {
    return target_->NewRandomAccessFile(f, r);
  }
  Status NewWritableFile(const std::string& f, WritableFile** r) override {
    return target_->NewWritableFile(f, r);
  }