ceph/src/librbd/operation/RenameRequest.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3
   4 #ifndef CEPH_LIBRBD_RENAME_REQUEST_H
   5 #define CEPH_LIBRBD_RENAME_REQUEST_H
   6
   7 #include "librbd/operation/Request.h"
   8 #include <string>
   9
  10 class Context;
  11
  12 namespace librbd {
  13
  14 class ImageCtx;
  15
  16 namespace operation {
  17
  18 template <typename ImageCtxT = ImageCtx>
  19 class RenameRequest : public Request<ImageCtxT>
  20 {
  21 public:
  22   /**
  23    * Rename goes through the following state machine:
  24    *
  25    * @verbatim
  26    *
  27    * <start>
  28    *    |
  29    *    v
  30    * STATE_READ_SOURCE_HEADER
  31    *    |
  32    *    v
  33    * STATE_WRITE_DEST_HEADER
  34    *    |
  35    *    v
  36    * STATE_UPDATE_DIRECTORY
  37    *    |
  38    *    v
  39    * STATE_REMOVE_SOURCE_HEADER
  40    *    |
  41    *    v
  42    * <finish>
  43    *
  44    * @endverbatim
  45    *
  46    */
  47   enum State {
  48     STATE_READ_SOURCE_HEADER,
  49     STATE_WRITE_DEST_HEADER,
  50     STATE_UPDATE_DIRECTORY,
  51     STATE_REMOVE_SOURCE_HEADER
  52   };
  53
  54   RenameRequest(ImageCtxT &image_ctx, Context *on_finish,
  55                 const std::string &dest_name);
  56
  57 protected:
  58   void send_op() override;
  59   bool should_complete(int r) override;
  60   int filter_return_code(int r) const override;
  61
  62   journal::Event create_event(uint64_t op_tid) const override {
  63     return journal::RenameEvent(op_tid, m_dest_name);
  64   }
  65
  66 private:
  67   std::string m_dest_name;
  68
  69   std::string m_source_oid;
  70   std::string m_dest_oid;
  71
  72   State m_state = STATE_READ_SOURCE_HEADER;
  73
  74   bufferlist m_header_bl;
  75
  76   void send_read_source_header();
  77   void send_write_destination_header();
  78   void send_update_directory();
  79   void send_remove_source_header();
  80
  81   void apply();
  82 };
  83
  84 } // namespace operation
  85 } // namespace librbd
  86
  87 extern template class librbd::operation::RenameRequest<librbd::ImageCtx>;
  88
  89 #endif // CEPH_LIBRBD_RENAME_REQUEST_H