ceph/src/messages/MMonSubscribe.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_MMONSUBSCRIBE_H
  16 #define CEPH_MMONSUBSCRIBE_H
  17
  18 #include "msg/Message.h"
  19 #include "include/ceph_features.h"
  20
  21 /*
  22  * compatibility with old crap
  23  */
  24 struct ceph_mon_subscribe_item_old {
  25         __le64 unused;
  26         __le64 have;
  27         __u8 onetime;
  28 } __attribute__ ((packed));
  29 WRITE_RAW_ENCODER(ceph_mon_subscribe_item_old)
  30
  31
  32 struct MMonSubscribe : public Message {
  33
  34   static const int HEAD_VERSION = 2;
  35
  36   map<string, ceph_mon_subscribe_item> what;
  37
  38   MMonSubscribe() : Message(CEPH_MSG_MON_SUBSCRIBE, HEAD_VERSION) { }
  39 private:
  40   ~MMonSubscribe() override {}
  41
  42 public:
  43   void sub_want(const char *w, version_t start, unsigned flags) {
  44     what[w].start = start;
  45     what[w].flags = flags;
  46   }
  47
  48   const char *get_type_name() const override { return "mon_subscribe"; }
  49   void print(ostream& o) const override {
  50     o << "mon_subscribe(" << what << ")";
  51   }
  52
  53   void decode_payload() override {
  54     bufferlist::iterator p = payload.begin();
  55     if (header.version < 2) {
  56       map<string, ceph_mon_subscribe_item_old> oldwhat;
  57       ::decode(oldwhat, p);
  58       what.clear();
  59       for (map<string, ceph_mon_subscribe_item_old>::iterator q = oldwhat.begin();
  60            q != oldwhat.end();
  61            q++) {
  62         if (q->second.have)
  63           what[q->first].start = q->second.have + 1;
  64         else
  65           what[q->first].start = 0;
  66         what[q->first].flags = 0;
  67         if (q->second.onetime)
  68           what[q->first].flags |= CEPH_SUBSCRIBE_ONETIME;
  69       }
  70     } else {
  71       ::decode(what, p);
  72     }
  73   }
  74   void encode_payload(uint64_t features) override {
  75     if (features & CEPH_FEATURE_SUBSCRIBE2) {
  76       ::encode(what, payload);
  77       header.version = HEAD_VERSION;
  78     } else {
  79       header.version = 0;
  80       map<string, ceph_mon_subscribe_item_old> oldwhat;
  81       for (map<string, ceph_mon_subscribe_item>::iterator q = what.begin();
  82            q != what.end();
  83            q++) {
  84         if (q->second.start)
  85           // warning: start=1 -> have=0, which was ambiguous
  86           oldwhat[q->first].have = q->second.start - 1;
  87         else
  88           oldwhat[q->first].have = 0;
  89         oldwhat[q->first].onetime = q->second.flags & CEPH_SUBSCRIBE_ONETIME;
  90       }
  91       ::encode(oldwhat, payload);
  92     }
  93   }
  94 };
  95
  96 #endif