ceph/src/common/ConfUtils.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) 2011 New Dream Network
   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_CONFUTILS_H
  16 #define CEPH_CONFUTILS_H
  17
  18 #include <deque>
  19 #include <map>
  20 #include <set>
  21 #include <string>
  22 #include <string_view>
  23 #include <vector>
  24
  25 #include "include/buffer_fwd.h"
  26
  27 /*
  28  * Ceph configuration file support.
  29  *
  30  * This class loads an INI-style configuration from a file or bufferlist, and
  31  * holds it in memory. In general, an INI configuration file is composed of
  32  * sections, which contain key/value pairs. You can put comments on the end of
  33  * lines by using either a hash mark (#) or the semicolon (;).
  34  *
  35  * You can get information out of ConfFile by calling get_key or by examining
  36  * individual sections.
  37  *
  38  * This class could be extended to support modifying configuration files and
  39  * writing them back out without too much difficulty. Currently, this is not
  40  * implemented, and the file is read-only.
  41  */
  42 struct conf_line_t  {
  43   conf_line_t() = default;
  44   conf_line_t(const std::string& key, const std::string& val);
  45   bool operator<(const conf_line_t& rhs) const;
  46   std::string key;
  47   std::string val;
  48 };
  49
  50 std::ostream &operator<<(std::ostream& oss, const conf_line_t& line);
  51
  52 class conf_section_t : public std::set<conf_line_t> {
  53 public:
  54   conf_section_t() = default;
  55   conf_section_t(const std::string& heading,
  56                  const std::vector<conf_line_t>& lines);
  57   std::string heading;
  58   friend std::ostream& operator<<(std::ostream& os, const conf_section_t&);
  59 };
  60
  61 class ConfFile : public std::map<std::string, conf_section_t> {
  62   using base_type = std::map<std::string, conf_section_t>;
  63 public:
  64   ConfFile()
  65     : ConfFile{std::vector<conf_section_t>{}}
  66   {}
  67   ConfFile(const conf_line_t& line)
  68     : ConfFile{{conf_section_t{"global", {line}}}}
  69   {}
  70   ConfFile(const std::vector<conf_section_t>& sections);
  71   int parse_file(const std::string &fname, std::ostream *warnings);
  72   int parse_bufferlist(ceph::bufferlist *bl, std::ostream *warnings);
  73   int read(const std::string& section, std::string_view key,
  74            std::string &val) const;
  75   static std::string normalize_key_name(std::string_view key);
  76 private:
  77   bool load_from_buffer(std::string_view buf, std::ostream* warning);
  78 };
  79
  80 std::ostream &operator<<(std::ostream& oss, const ConfFile& cf);
  81
  82 #endif