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 #ifndef ARGUMENTS_HH
  23 #define ARGUMENTS_HH
  24
  25 #include <map>
  26 #include <set>
  27 #include <string>
  28 #include <vector>
  29 #include <fstream>
  30 #include <iostream>
  31 #include "misc.hh"
  32 #include "pdnsexception.hh"
  33 #include <sys/types.h>
  34 #include <pwd.h>
  35 #include <grp.h>
  36
  37 #include "namespaces.hh"
  38
  39 typedef PDNSException ArgException;
  40
  41 /** This class helps parsing argc and argv into a map of parameters. We have 3 kinds of formats:
  42
  43
  44     -w           this leads to a key/value pair of "w"/void
  45
  46     --port=25    "port"/"25"
  47
  48     --daemon     "daemon"/void
  49
  50     We do not support "--port 25" syntax.
  51
  52     It can also read from a file. This file can contain '#' to delimit comments.
  53
  54     Some sample code:
  55
  56     \code
  57
  58     ArgvMap R;
  59
  60     R.set("port")="25";  // use this to specify default parameters
  61     R.file("./default.conf"); // parse configuration file
  62
  63     R.parse(argc, argv); // read the arguments from main()
  64
  65     cout<<"Will we be a daemon?: "<<R.isset("daemon")<<endl;
  66     cout<<"Our port will be "<<R["port"]<<endl;
  67
  68     map<string,string>::const_iterator i;
  69     cout<<"via iterator"<<endl;
  70     for(i=R.begin();i!=R.end();i++)
  71     cout<<i->first<<"="<<i->second<<endl;
  72     \endcode
  73 */
  74
  75
  76
  77 class ArgvMap
  78 {
  79 public:
  80   ArgvMap();
  81   void parse(int &argc, char **argv, bool lax=false); //!< use this to parse from argc and argv
  82   void laxParse(int &argc, char **argv) //!< use this to parse from argc and argv
  83   {
  84     parse(argc,argv,true);
  85   }
  86   void preParse(int &argc, char **argv, const string &arg); //!< use this to preparse a single var
  87   bool preParseFile(const char *fname, const string &arg, const string& theDefault=""); //!< use this to preparse a single var in configuration
  88
  89   bool file(const char *fname, bool lax=false); //!< Parses a file with parameters
  90   bool file(const char *fname, bool lax, bool included);
  91   bool laxFile(const char *fname)
  92   {
  93     return file(fname,true);
  94   }
  95   bool parseFile(const char *fname, const string& arg, bool lax); //<! parse one line
  96   typedef map<string,string> param_t; //!< use this if you need to know the content of the map
  97   bool parmIsset(const string &var); //!< Checks if a parameter is set to *a* value
  98   bool mustDo(const string &var); //!< if a switch is given, if we must do something (--help)
  99   int asNum(const string &var, int def=0); //!< return a variable value as a number or the default if the variable is empty
 100   mode_t asMode(const string &var); //!< return value interpreted as octal number
 101   uid_t asUid(const string &var); //!< return user id, resolves if necessary
 102   gid_t asGid(const string &var); //!< return group id, resolves if necessary
 103   double asDouble(const string &var); //!< return a variable value as a number
 104   string &set(const string &); //!< Gives a writable reference and allocates space for it
 105   string &set(const string &, const string &); //!< Does the same but also allows one to specify a help message
 106   void setCmd(const string &, const string &); //!< Add a command flag
 107   string &setSwitch(const string &, const string &); //!< Add a command flag
 108   string helpstring(string prefix=""); //!< generates the --help
 109   string configstring(bool current=false); //!< generates the --mkconfig
 110   bool contains(const string &var, const string &val);
 111   bool isEmpty(const string &var); //!< checks if variable has value
 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> d_typeMap;
 127   vector<string> d_cmds;
 128   std::set<string> d_cleared;
 129 };
 130
 131 extern ArgvMap &arg();
 132
 133 #endif /* ARGUMENTS_HH */