ceph/src/messages/MClientSession.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph - scalable distributed file system
   5  *
   6  * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
   7  *
   8  * This is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License version 2.1, as published by the Free Software
  11  * Foundation.  See file COPYING.
  12  *
  13  */
  14
  15 #ifndef CEPH_MCLIENTSESSION_H
  16 #define CEPH_MCLIENTSESSION_H
  17
  18 #include "msg/Message.h"
  19
  20 class MClientSession : public Message {
  21   static const int HEAD_VERSION = 2;
  22   static const int COMPAT_VERSION = 1;
  23
  24 public:
  25   ceph_mds_session_head head;
  26
  27   std::map<std::string, std::string> client_meta;
  28
  29   int get_op() const { return head.op; }
  30   version_t get_seq() const { return head.seq; }
  31   utime_t get_stamp() const { return utime_t(head.stamp); }
  32   int get_max_caps() const { return head.max_caps; }
  33   int get_max_leases() const { return head.max_leases; }
  34
  35   MClientSession() : Message(CEPH_MSG_CLIENT_SESSION, HEAD_VERSION, COMPAT_VERSION) { }
  36   MClientSession(int o, version_t s=0) :
  37     Message(CEPH_MSG_CLIENT_SESSION, HEAD_VERSION, COMPAT_VERSION) {
  38     memset(&head, 0, sizeof(head));
  39     head.op = o;
  40     head.seq = s;
  41   }
  42   MClientSession(int o, utime_t st) :
  43     Message(CEPH_MSG_CLIENT_SESSION, HEAD_VERSION, COMPAT_VERSION) {
  44     memset(&head, 0, sizeof(head));
  45     head.op = o;
  46     head.seq = 0;
  47     st.encode_timeval(&head.stamp);
  48   }
  49 private:
  50   ~MClientSession() override {}
  51
  52 public:
  53   const char *get_type_name() const override { return "client_session"; }
  54   void print(ostream& out) const override {
  55     out << "client_session(" << ceph_session_op_name(get_op());
  56     if (get_seq())
  57       out << " seq " << get_seq();
  58     if (get_op() == CEPH_SESSION_RECALL_STATE)
  59       out << " max_caps " << head.max_caps << " max_leases " << head.max_leases;
  60     out << ")";
  61   }
  62
  63   void decode_payload() override {
  64     bufferlist::iterator p = payload.begin();
  65     ::decode(head, p);
  66     if (header.version >= 2) {
  67       ::decode(client_meta, p);
  68     }
  69   }
  70   void encode_payload(uint64_t features) override {
  71     ::encode(head, payload);
  72     if (client_meta.empty()) {
  73       // If we're not trying to send any metadata (always the case if
  74       // we are a server) then send older-format message to avoid upsetting
  75       // old kernel clients.
  76       header.version = 1;
  77     } else {
  78       ::encode(client_meta, payload);
  79       header.version = HEAD_VERSION;
  80     }
  81
  82   }
  83 };
  84
  85 #endif