ceph/src/tools/RadosDump.cc

   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) 2015 Red Hat
   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 #include "RadosDump.h"
  16
  17 int RadosDump::read_super()
  18 {
  19   bufferlist ebl;
  20   bufferlist::iterator ebliter = ebl.begin();
  21   ssize_t bytes;
  22
  23   bytes = ebl.read_fd(file_fd, super_header::FIXED_LENGTH);
  24   if ((size_t)bytes != super_header::FIXED_LENGTH) {
  25     cerr << "Unexpected EOF" << std::endl;
  26     return -EFAULT;
  27   }
  28
  29   sh.decode(ebliter);
  30
  31   return 0;
  32 }
  33
  34
  35 int RadosDump::get_header(header *h)
  36 {
  37   assert (h != NULL);
  38
  39   bufferlist ebl;
  40   bufferlist::iterator ebliter = ebl.begin();
  41   ssize_t bytes;
  42
  43   bytes = ebl.read_fd(file_fd, sh.header_size);
  44   if ((size_t)bytes != sh.header_size) {
  45     cerr << "Unexpected EOF" << std::endl;
  46     return -EFAULT;
  47   }
  48
  49   h->decode(ebliter);
  50
  51   return 0;
  52 }
  53
  54 int RadosDump::get_footer(footer *f)
  55 {
  56   assert(f != NULL);
  57
  58   bufferlist ebl;
  59   bufferlist::iterator ebliter = ebl.begin();
  60   ssize_t bytes;
  61
  62   bytes = ebl.read_fd(file_fd, sh.footer_size);
  63   if ((size_t)bytes != sh.footer_size) {
  64     cerr << "Unexpected EOF" << std::endl;
  65     return -EFAULT;
  66   }
  67
  68   f->decode(ebliter);
  69
  70   if (f->magic != endmagic) {
  71     cerr << "Bad footer magic" << std::endl;
  72     return -EFAULT;
  73   }
  74
  75   return 0;
  76 }
  77
  78 int RadosDump::read_section(sectiontype_t *type, bufferlist *bl)
  79 {
  80   header hdr;
  81   ssize_t bytes;
  82
  83   int ret = get_header(&hdr);
  84   if (ret)
  85     return ret;
  86
  87   *type = hdr.type;
  88
  89   bl->clear();
  90   bytes = bl->read_fd(file_fd, hdr.size);
  91   if (bytes != hdr.size) {
  92     cerr << "Unexpected EOF" << std::endl;
  93     return -EFAULT;
  94   }
  95
  96   if (hdr.size > 0) {
  97     footer ft;
  98     ret = get_footer(&ft);
  99     if (ret)
 100       return ret;
 101   }
 102
 103   return 0;
 104 }
 105
 106
 107 int RadosDump::skip_object(bufferlist &bl)
 108 {
 109   bufferlist::iterator ebliter = bl.begin();
 110   bufferlist ebl;
 111   bool done = false;
 112   while(!done) {
 113     sectiontype_t type;
 114     int ret = read_section(&type, &ebl);
 115     if (ret)
 116       return ret;
 117
 118     ebliter = ebl.begin();
 119     if (type >= END_OF_TYPES) {
 120       cout << "Skipping unknown object section type" << std::endl;
 121       continue;
 122     }
 123     switch(type) {
 124     case TYPE_DATA:
 125     case TYPE_ATTRS:
 126     case TYPE_OMAP_HDR:
 127     case TYPE_OMAP:
 128 #ifdef DIAGNOSTIC
 129       cerr << "Skip type " << (int)type << std::endl;
 130 #endif
 131       break;
 132     case TYPE_OBJECT_END:
 133       done = true;
 134       break;
 135     default:
 136       cerr << "Can't skip unknown type: " << type << std::endl;
 137       return -EFAULT;
 138     }
 139   }
 140   return 0;
 141 }
 142
 143 //Write super_header with its fixed 16 byte length
 144 void RadosDump::write_super()
 145 {
 146   if (dry_run) {
 147     return;
 148   }
 149
 150   bufferlist superbl;
 151   super_header sh;
 152   footer ft;
 153
 154   header hdr(TYPE_NONE, 0);
 155   hdr.encode(superbl);
 156
 157   sh.magic = super_header::super_magic;
 158   sh.version = super_header::super_ver;
 159   sh.header_size = superbl.length();
 160   superbl.clear();
 161   ft.encode(superbl);
 162   sh.footer_size = superbl.length();
 163   superbl.clear();
 164
 165   sh.encode(superbl);
 166   assert(super_header::FIXED_LENGTH == superbl.length());
 167   superbl.write_fd(file_fd);
 168 }