Poor-Mans-IDS/miniini.h

//////////////////////////////////////////////////////////////////////
// Mini INI File Crackers
// Written by Jonathan A. Foster <jon@jfpossibilities.com>
// Started June 1st, 2021
// Copyright JF Possibilities, Inc. All rights reserved.
// Used with permission in the "Poor Man's IDS" project
//
// This set of classes is to prvide easy access to reading config data
// from INI files. I'm going to take some liberty with the origianl
// M$ format and allow groups to parse specialized text formats, not
// just name/value pairs.
//////////////////////////////////////////////////////////////////////
#ifndef __JFP_MINIINI_H__
#define __JFP_MINIINI_H__
#include  <string>
#include  <ostream>
#include  "strutil.h"



//////////////////////////////////////////////////////////////////////
// The base abstract group class
//
// Subclass and override this class to create a parser for the kind of
// data you want in your group.
//////////////////////////////////////////////////////////////////////
struct MiniINI;

struct MiniINIgroup {
  // vals: By convention the content of the group

  // this is overriden to handle the parsing of lines in this group
  // it must ignore whitespace and remarks, if allowed in the group's
  // format.
  virtual void add(const std::string &in) = 0;
  // This is overridden to dump the group back out to a file
  virtual std::ostream &save(std::ostream &out) const = 0;
  // cause we need the destructor virtual too!
  virtual ~MiniINIgroup() {}
};
inline std::ostream &operator<<(std::ostream &out, const MiniINIgroup &ini) {
  return ini.save(out);
}



//////////////////////////////////////////////////////////////////////
// The typical collection of name+value pairs
//////////////////////////////////////////////////////////////////////

struct MiniINIvars: public MiniINIgroup {
  NameVal vals; // name val pairs

  /// Get a value setting it to def if not found
  ///
  /// This looks for name in vals. If found that value is returned. Otherwise
  /// the def is set in vals for the name. This means it will be saved at
  /// next writing. Def defaults to empty string. If you don't want to auto-
  /// create the value in the config file then use the appropriate methods of
  /// vals.
  virtual std::string get(const std::string &name, const std::string &def);

  /// Get a value NOT adding it to vals if not found
  ///
  /// This looks for name in vals. If found that value is returned. Otherwise
  /// "" is returned but the name is not added to vals.
  virtual std::string get(const std::string &name) const;

  /// Get an int from vals
  ///
  /// This will convert the string value, if found in vals, to an int and make
  /// sure its within bounds. If its not in bounds or doesn't exist or is an
  /// an empty string them def is returned. The vals is not modified.
  ///
  /// For safety values are limited to 9 digits plus sign, since this is a safe
  /// range for converting to 32 bit ints.
  virtual int geti(const std::string &name, int def=0, int min=-999999999, int max=999999999) const;

  /// parse an INI line into a name value pair
  virtual void add(const std::string &in);

  /// write all name value pairs from vals to out
  virtual std::ostream &save(std::ostream &out) const;
};



//////////////////////////////////////////////////////////////////////
// A raw collection of lines in a group
//////////////////////////////////////////////////////////////////////

struct MiniINIlines: public MiniINIgroup {
  StringList vals;        // the raw lines of this group
  virtual void add(const std::string &in);// add an incoming line
  virtual std::ostream &save(std::ostream &out) const;
};



//////////////////////////////////////////////////////////////////////
// The main INI container that contains all groups
//
// Fill groups with a list of group objects and their associated
// names. Call load() to read the groups from an INI file. Only the
// group with names specified in groups will be read. Their content
// parsed according to the group's rules. save() will write it back
// out again. No attempt to preserve whitespace and remarks is made.
//////////////////////////////////////////////////////////////////////

typedef std::map<std::string,MiniINIgroup*> INIgroupList;
struct MiniINI {
  // This is a list of groups allowed in the INI and after load() those
  // groups will contain the data from the INI and they will be written
  // on save().
  //
  // This must be initialized with MiniINIgroup* objects so that it knows
  // how to process groups. No attempt is made to manage memory allocation.
  INIgroupList groups;

  // Load the file and parse into groups[]. If a group is encountered that
  // was not specified in groups[] it is ignored, and will be lost on
  // save(). Same for pre-group content.
  virtual void load(const std::string &fname);

  // Save the groups[] into the file. No attempt is made to preserve
  // whitespace or remarks. This is the "mini INI". Preserving thoee
  // requires a more complicated and thus less "mini" implementation.
  virtual void save(const std::string &fname);

  // A virtual NOP destructor... because its recommended.
  virtual ~MiniINI() {}
};



#endif