livestatus/src/Logfile.h

   1 // +------------------------------------------------------------------+
   2 // |             ____ _               _        __  __ _  __           |
   3 // |            / ___| |__   ___  ___| | __   |  \/  | |/ /           |
   4 // |           | |   | '_ \ / _ \/ __| |/ /   | |\/| | ' /            |
   5 // |           | |___| | | |  __/ (__|   <    | |  | | . \            |
   6 // |            \____|_| |_|\___|\___|_|\_\___|_|  |_|_|\_\           |
   7 // |                                                                  |
   8 // | Copyright Mathias Kettner 2014             mk@mathias-kettner.de |
   9 // +------------------------------------------------------------------+
  10 //
  11 // This file is part of Check_MK.
  12 // The official homepage is at http://mathias-kettner.de/check_mk.
  13 //
  14 // check_mk is free software;  you can redistribute it and/or modify it
  15 // under the  terms of the  GNU General Public License  as published by
  16 // the Free Software Foundation in version 2.  check_mk is  distributed
  17 // in the hope that it will be useful, but WITHOUT ANY WARRANTY;  with-
  18 // out even the implied warranty of  MERCHANTABILITY  or  FITNESS FOR A
  19 // PARTICULAR PURPOSE. See the  GNU General Public License for more de-
  20 // tails. You should have  received  a copy of the  GNU  General Public
  21 // License along with GNU Make; see the file  COPYING.  If  not,  write
  22 // to the Free Software Foundation, Inc., 51 Franklin St,  Fifth Floor,
  23 // Boston, MA 02110-1301 USA.
  24
  25 #ifndef Logfile_h
  26 #define Logfile_h
  27
  28 #include "config.h"  // IWYU pragma: keep
  29 #include <cstdint>
  30 #include <cstdio>
  31 #include <ctime>
  32 #include <map>
  33 #include <memory>
  34 #include <string>
  35 #include "FileSystem.h"
  36 class LogCache;
  37 class LogEntry;
  38 class Logger;
  39 class MonitoringCore;
  40 class Query;
  41
  42 #ifdef CMC
  43 class World;
  44 #endif
  45
  46 // key is time_t . lineno
  47 using logfile_entries_t = std::map<uint64_t, std::unique_ptr<LogEntry>>;
  48
  49 class Logfile {
  50 public:
  51     Logfile(MonitoringCore *mc, LogCache *logcache, fs::path path, bool watch);
  52     fs::path path() const { return _path; }
  53
  54     // for tricky protocol between LogCache::logLineHasBeenAdded and this class
  55     void flush();
  56     time_t since() const { return _since; }
  57     unsigned classesRead() const { return _logclasses_read; }
  58     size_t size() const { return _entries.size(); }
  59     long freeMessages(unsigned logclasses);
  60
  61     // for TableStateHistory
  62     const logfile_entries_t *getEntriesFor(unsigned logclasses);
  63
  64     // for TableLog::answerQuery
  65     bool answerQueryReverse(Query *query, time_t since, time_t until,
  66                             unsigned logclasses);
  67
  68 private:
  69     MonitoringCore *const _mc;
  70     LogCache *const _logcache;
  71     const fs::path _path;
  72     const time_t _since;  // time of first entry
  73     const bool _watch;    // true only for current logfile
  74     fpos_t _read_pos;     // read until this position
  75     size_t _lineno;       // read until this line
  76     logfile_entries_t _entries;
  77 #ifdef CMC
  78     World *_world;  // CMC: world our references point into
  79 #endif
  80     unsigned _logclasses_read;  // only these types have been read
  81
  82     void load(unsigned logclasses);
  83     void loadRange(FILE *file, unsigned missing_types, unsigned logclasses);
  84     bool processLogLine(size_t lineno, std::string line, unsigned logclasses);
  85     uint64_t makeKey(time_t t, size_t lineno);
  86     void updateReferences();
  87     Logger *logger() const;
  88 };
  89
  90 #endif  // Logfile_h