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
  37 typedef PDNSException ArgException;
  38
  39 /** This class helps parsing argc and argv into a map of parameters. We have 3 kinds of formats:
  40
  41
  42     -w           this leads to a key/value pair of "w"/void
  43
  44     --port=25    "port"/"25"
  45
  46     --daemon     "daemon"/void
  47
  48     We do not support "--port 25" syntax.
  49
  50     It can also read from a file. This file can contain '#' to delimit comments.
  51
  52     Some sample code:
  53
  54     \code
  55
  56     ArgvMap R;
  57
  58     R.set("port")="25";  // use this to specify default parameters
  59     R.file("./default.conf"); // parse configuration file
  60
  61     R.parse(argc, argv); // read the arguments from main()
  62
  63     cout<<"Will we be a daemon?: "<<R.isset("daemon")<<endl;
  64     cout<<"Our port will be "<<R["port"]<<endl;
  65
  66     map<string,string>::const_iterator i;
  67     cout<<"via iterator"<<endl;
  68     for(i=R.begin();i!=R.end();i++)
  69     cout<<i->first<<"="<<i->second<<endl;
  70     \endcode
  71 */
  72
  73
  74
  75 class ArgvMap
  76 {
  77 public:
  78   ArgvMap();
  79   void parse(int &argc, char **argv, bool lax=false); //!< use this to parse from argc and argv
  80   void laxParse(int &argc, char **argv) //!< use this to parse from argc and argv
  81   {
  82     parse(argc,argv,true);
  83   }
  84   void preParse(int &argc, char **argv, const string &arg); //!< use this to preparse a single var
  85   bool preParseFile(const char *fname, const string &arg, const string& theDefault=""); //!< use this to preparse a single var in configuration
  86
  87   bool file(const char *fname, bool lax=false); //!< Parses a file with parameters
  88   bool file(const char *fname, bool lax, bool included);
  89   bool laxFile(const char *fname)
  90   {
  91     return file(fname,true);
  92   }
  93   bool parseFile(const char *fname, const string& arg, bool lax); //<! parse one line
  94   typedef map<string,string> param_t; //!< use this if you need to know the content of the map
  95   bool parmIsset(const string &var); //!< Checks if a parameter is set to *a* value
  96   bool mustDo(const string &var); //!< if a switch is given, if we must do something (--help)
  97   int asNum(const string &var, int def=0); //!< return a variable value as a number or the default if the variable is empty
  98   mode_t asMode(const string &var); //!< return value interpreted as octal number
  99   uid_t asUid(const string &var); //!< return user id, resolves if necessary
 100   gid_t asGid(const string &var); //!< return group id, resolves if necessary
 101   double asDouble(const string &var); //!< return a variable value as a number
 102   string &set(const string &); //!< Gives a writable reference and allocates space for it
 103   string &set(const string &, const string &); //!< Does the same but also allows one to specify a help message
 104   void setCmd(const string &, const string &); //!< Add a command flag
 105   string &setSwitch(const string &, const string &); //!< Add a switch flag
 106   string helpstring(string prefix=""); //!< generates the --help
 107   string configstring(bool current, bool full); //!< generates the --config
 108   bool contains(const string &var, const string &val);
 109   bool isEmpty(const string &var); //!< checks if variable has value
 110   void setDefault(const string &var, const string &value);
 111   void setDefaults();
 112
 113   vector<string>list();
 114   string getHelp(const string &item);
 115
 116   const param_t::const_iterator begin(); //!< iterator semantics
 117   const param_t::const_iterator end(); //!< iterator semantics
 118   const string &operator[](const string &); //!< iterator semantics
 119   const vector<string>&getCommands();
 120   void gatherIncludes(std::vector<std::string> &extraConfigs);
 121 private:
 122   void parseOne(const string &unparsed, const string &parseOnly="", bool lax=false);
 123   typedef map<string,string> params_t;
 124   params_t params;
 125   map<string,string> helpmap;
 126   map<string,string> defaultmap;
 127   map<string,string> d_typeMap;
 128   vector<string> d_cmds;
 129   std::set<string> d_cleared;
 130 };
 131
 132 extern ArgvMap &arg();