src/restore.h

   1 ///
   2 /// \file       restore.h
   3 ///             Builder class for restoring from Barry Backup files
   4 ///
   5
   6 /*
   7     Copyright (C) 2010-2011, Net Direct Inc. (http://www.netdirect.ca/)
   8
   9     This program is free software; you can redistribute it and/or modify
  10     it under the terms of the GNU General Public License as published by
  11     the Free Software Foundation; either version 2 of the License, or
  12     (at your option) any later version.
  13
  14     This program is distributed in the hope that it will be useful,
  15     but WITHOUT ANY WARRANTY; without even the implied warranty of
  16     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  17
  18     See the GNU General Public License in the COPYING file at the
  19     root directory of this project for more details.
  20 */
  21
  22 #ifndef __BARRYBACKUP_RESTORE_H__
  23 #define __BARRYBACKUP_RESTORE_H__
  24
  25 #include "dll.h"
  26 #include "builder.h"
  27 #include "configfile.h"
  28 #include <string>
  29 #include <vector>
  30 #include <memory>
  31
  32 // forward declarations
  33 namespace reuse {
  34         class TarFile;
  35 }
  36
  37 namespace Barry {
  38
  39 //
  40 // Restore
  41 //
  42 /// Barry Backup Restore builder class.  This class is suitable
  43 /// to be used as a builder object anywhere a builder object is
  44 /// accepted.  It reads from a Barry Backup tar.gz backup file,
  45 /// and builds records in a staged manner.
  46 ///
  47 /// If a backup file contains more than one database (for example
  48 /// both Address Book and Calendar), then it will build one database
  49 /// first, return false on Retrieve(), and then build the next.
  50 /// If Retrieve() returns false, but EndOfFile() also returns false,
  51 /// then more databases are available.
  52 ///
  53 /// The idea is that you can call Desktop::SaveDatabase() multiple
  54 /// times with this same Restore object, for all the databases in
  55 /// the backup file.
  56 ///
  57 /// It is safe to call Retrieve() multiple times, so when first
  58 /// starting a restore:
  59 ///     - call the constructor
  60 ///     - call AddDB() with any filters
  61 ///     - then call Retrieve(), which will grab the first record,
  62 ///       and make GetDBName() valid.
  63 ///
  64 class BXEXPORT Restore : public Barry::Builder
  65 {
  66 public:
  67         typedef Barry::ConfigFile::DBListType           DBListType;
  68
  69 private:
  70         enum RetrievalState
  71         {
  72                 RS_EMPTY,       // no record loaded
  73                 RS_UNKNOWN,     // record data loaded, but not yet checked
  74                                 // whether this is part of current database
  75                 RS_NEXT,        // record loaded, part of current database
  76                 RS_DBEND,       // next record loaded, but end-of-database
  77                                 // not yet processed by Builder API
  78                 RS_EOF          // no recrd loaded, end of tar file
  79         };
  80
  81         DBListType m_dbList;
  82
  83         std::string m_tarpath;
  84         std::auto_ptr<reuse::TarFile> m_tar;
  85
  86         bool m_default_all_db;
  87         RetrievalState m_tar_record_state;
  88         uint8_t m_rec_type;
  89         uint32_t m_unique_id;
  90         std::string m_current_dbname;
  91         Barry::Data m_record_data;
  92         std::string m_tar_id_text;
  93
  94 protected:
  95         static bool SplitTarPath(const std::string &tarpath,
  96                 std::string &dbname, std::string &dbid_text,
  97                 uint8_t &dbrectype, uint32_t &dbid);
  98
  99         bool IsSelected(const std::string &dbName) const;
 100         RetrievalState Retrieve(Data &record_data);
 101
 102
 103 public:
 104         /// If default_all_db is true, and none of the Add*() functions
 105         /// are called (meaning that Restore has an empty database list),
 106         /// then all records are restored.  If false in this situation,
 107         /// nothing is restored.
 108         ///
 109         /// If any of the Add*() functions are called, then the database
 110         /// list takes precedence, and default_all_db has no effect.
 111         ///
 112         explicit Restore(const std::string &tarpath,
 113                         bool default_all_db = true);
 114         ~Restore();
 115
 116         /// Add database name to the read filter.
 117         void AddDB(const std::string &dbName);
 118
 119         /// Add all database names in dblist to the read filter
 120         /// This function is additive.
 121         void Add(const DBListType &dbList);
 122
 123         // Skip the current DB, in case of error, or preference
 124         void SkipCurrentDB();
 125
 126         /// Loads the given file, and counts all records according
 127         /// to the current read filter.  Does not use the main
 128         /// Restore file, but opens the file separately.
 129         /// It is safe to call this function as often as needed.
 130         unsigned int GetRecordTotal() const;
 131
 132         /// Static version of above call
 133         static unsigned int GetRecordTotal(const std::string &tarpath,
 134                 const DBListType &dbList, bool default_all_db);
 135
 136         /// If this function returns true, it fills data with the
 137         /// meta data that the next call to BuildRecord() will retrieve.
 138         /// This is useful for applications that need to setup a manual
 139         /// call to Desktop::SaveDatabase().
 140         bool GetNextMeta(DBData &data);
 141
 142         // Barry::Builder overrides
 143         bool BuildRecord(Barry::DBData &data, size_t &offset,
 144                 const Barry::IConverter *ic);
 145         bool FetchRecord(Barry::DBData &data, const Barry::IConverter *ic);
 146         bool EndOfFile() const;
 147 };
 148
 149 } // namespace Barry
 150
 151 #endif
 152