pdns/arguments.hh

   1 /*
   2  * This file is part of PowerDNS or dnsdist.
   3  * Copyright -- PowerDNS.COM B.V. and its contributors
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * In addition, for the avoidance of any doubt, permission is granted to
  10  * link this program with OpenSSL and to (re)distribute the binaries
  11  * produced as the result of such linking.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22 #pragma once
  23 #include <map>
  24 #include <set>
  25 #include <string>
  26 #include <vector>
  27 #include <fstream>
  28 #include <iostream>
  29 #include "misc.hh"
  30 #include "pdnsexception.hh"
  31 #include <sys/types.h>
  32 #include <pwd.h>
  33 #include <grp.h>
  34
  35 #include "namespaces.hh"
  36 #include "logging.hh"
  37
  38 using ArgException = PDNSException;
  39
  40 /** This class helps parsing argc and argv into a map of parameters. We have 3 kinds of formats:
  41
  42
  43     -w           this leads to a key/value pair of "w"/void
  44
  45     --port=25    "port"/"25"
  46
  47     --daemon     "daemon"/void
  48
  49     We do not support "--port 25" syntax.
  50
  51     It can also read from a file. This file can contain '#' to delimit comments.
  52
  53     Some sample code:
  54
  55     \code
  56
  57     ArgvMap R;
  58
  59     R.set("port")="25";  // use this to specify default parameters
  60     R.file("./default.conf"); // parse configuration file
  61
  62     R.parse(argc, argv); // read the arguments from main()
  63
  64     cout<<"Will we be a daemon?: "<<R.isset("daemon")<<endl;
  65     cout<<"Our port will be "<<R["port"]<<endl;
  66
  67     map<string,string>::const_iterator i;
  68     cout<<"via iterator"<<endl;
  69     for(i=R.begin();i!=R.end();i++)
  70     cout<<i->first<<"="<<i->second<<endl;
  71     \endcode
  72 */
  73
  74 class ArgvMap
  75 {
  76 public:
  77   ArgvMap();
  78   void parse(int& argc, char** argv, bool lax = false); //!< use this to parse from argc and argv
  79   void laxParse(int& argc, char** argv) //!< use this to parse from argc and argv
  80   {
  81     parse(argc, argv, true);
  82   }
  83   void preParse(int& argc, char** argv, const string& arg); //!< use this to preparse a single var
  84   bool preParseFile(const string& fname, const string& arg, const string& theDefault = ""); //!< use this to preparse a single var in configuration
  85
  86   bool file(const string& fname, bool lax = false); //!< Parses a file with parameters
  87   bool file(const string& fname, bool lax, bool included);
  88   bool laxFile(const string& fname)
  89   {
  90     return file(fname, true);
  91   }
  92   bool parseFile(const string& fname, const string& arg, bool lax); //<! parse one line
  93   bool parmIsset(const string& var); //!< Checks if a parameter is set to *a* value
  94   bool mustDo(const string& var); //!< if a switch is given, if we must do something (--help)
  95   int asNum(const string& arg, int def = 0); //!< return a variable value as a number or the default if the variable is empty
  96   mode_t asMode(const string& arg); //!< return value interpreted as octal number
  97   uid_t asUid(const string& arg); //!< return user id, resolves if necessary
  98   gid_t asGid(const string& arg); //!< return group id, resolves if necessary
  99   double asDouble(const string& arg); //!< return a variable value as a number
 100   string& set(const string&); //!< Gives a writable reference and allocates space for it
 101   string& set(const string&, const string&); //!< Does the same but also allows one to specify a help message
 102   void setCmd(const string&, const string&); //!< Add a command flag
 103   string& setSwitch(const string&, const string&); //!< Add a switch flag
 104   string helpstring(string prefix = ""); //!< generates the --help
 105   string configstring(bool running, bool full); //!< generates the --config
 106   bool contains(const string& var, const string& val);
 107   bool isEmpty(const string& arg); //!< checks if variable has value
 108   void setDefault(const string& var, const string& value);
 109   void setDefaults();
 110
 111   vector<string> list();
 112   [[nodiscard]] string getHelp(const string& item) const
 113   {
 114     auto iter = helpmap.find(item);
 115     return iter == helpmap.end() ? "" : iter->second;
 116   }
 117   [[nodiscard]] string getDefault(const string& item) const
 118   {
 119     auto iter = defaultmap.find(item);
 120     return iter == defaultmap.end() ? "" : iter->second;
 121   }
 122   using param_t = map<string, string>; //!< use this if you need to know the content of the map
 123
 124   param_t::const_iterator begin(); //!< iterator semantics
 125   param_t::const_iterator end(); //!< iterator semantics
 126   const string& operator[](const string&); //!< iterator semantics
 127   const vector<string>& getCommands();
 128   void gatherIncludes(const std::string& dir, const std::string& suffix, std::vector<std::string>& extraConfigs);
 129   void warnIfDeprecated(const string& var) const;
 130   [[nodiscard]] static string isDeprecated(const string& var);
 131 #ifdef RECURSOR
 132   void setSLog(Logr::log_t log)
 133   {
 134     d_log = log;
 135   }
 136 #endif
 137 private:
 138   void parseOne(const string& arg, const string& parseOnly = "", bool lax = false);
 139   static string formatOne(bool running, bool full, const string& var, const string& help, const string& theDefault, const string& current);
 140   map<string, string> d_params;
 141   map<string, string> d_unknownParams;
 142   map<string, string> helpmap;
 143   map<string, string> defaultmap;
 144   map<string, string> d_typeMap;
 145   vector<string> d_cmds;
 146   std::set<string> d_cleared;
 147 #ifdef RECURSOR
 148   std::shared_ptr<Logr::Logger> d_log;
 149 #endif
 150 };
 151
 152 extern ArgvMap& arg();