ceph/src/rocksdb/utilities/trace/file_trace_reader_writer.h

   1 //  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
   2 //  This source code is licensed under both the GPLv2 (found in the
   3 //  COPYING file in the root directory) and Apache 2.0 License
   4 //  (found in the LICENSE.Apache file in the root directory).
   5
   6 #pragma once
   7
   8 #include "rocksdb/trace_reader_writer.h"
   9
  10 namespace ROCKSDB_NAMESPACE {
  11
  12 class RandomAccessFileReader;
  13 class WritableFileWriter;
  14
  15 // FileTraceReader allows reading RocksDB traces from a file.
  16 class FileTraceReader : public TraceReader {
  17  public:
  18   explicit FileTraceReader(std::unique_ptr<RandomAccessFileReader>&& reader);
  19   ~FileTraceReader();
  20
  21   virtual Status Read(std::string* data) override;
  22   virtual Status Close() override;
  23   virtual Status Reset() override;
  24
  25  private:
  26   std::unique_ptr<RandomAccessFileReader> file_reader_;
  27   Slice result_;
  28   size_t offset_;
  29   char* const buffer_;
  30
  31   static const unsigned int kBufferSize;
  32 };
  33
  34 // FileTraceWriter allows writing RocksDB traces to a file.
  35 class FileTraceWriter : public TraceWriter {
  36  public:
  37   explicit FileTraceWriter(std::unique_ptr<WritableFileWriter>&& file_writer);
  38   ~FileTraceWriter();
  39
  40   virtual Status Write(const Slice& data) override;
  41   virtual Status Close() override;
  42   virtual uint64_t GetFileSize() override;
  43
  44  private:
  45   std::unique_ptr<WritableFileWriter> file_writer_;
  46 };
  47
  48 }  // namespace ROCKSDB_NAMESPACE