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- // ConfigFile.h
- // Class for reading named values from configuration files
- // Richard J. Wagner v2.1 24 May 2004 wagnerr@umich.edu
-
- // Copyright (c) 2004 Richard J. Wagner
- //
- // Permission is hereby granted, free of charge, to any person obtaining a copy
- // of this software and associated documentation files (the "Software"), to
- // deal in the Software without restriction, including without limitation the
- // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
- // sell copies of the Software, and to permit persons to whom the Software is
- // furnished to do so, subject to the following conditions:
- //
- // The above copyright notice and this permission notice shall be included in
- // all copies or substantial portions of the Software.
- //
- // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
- // IN THE SOFTWARE.
-
- // Typical usage
- // -------------
- //
- // Given a configuration file "settings.inp":
- // atoms = 25
- // length = 8.0 # nanometers
- // name = Reece Surcher
- //
- // Named values are read in various ways, with or without default values:
- // ConfigFile config( "settings.inp" );
- // int atoms = config.read<int>( "atoms" );
- // double length = config.read( "length", 10.0 );
- // string author, title;
- // config.readInto( author, "name" );
- // config.readInto( title, "title", string("Untitled") );
- //
- // See file example.cpp for more examples.
-
- #ifndef CONFIGFILE_H
- #define CONFIGFILE_H
-
- #include <string>
- #include <map>
- #include <iostream>
- #include <fstream>
- #include <sstream>
-
- using std::string;
-
- class ConfigFile {
- // Data
- protected:
- string myDelimiter; // separator between key and value
- string myComment; // separator between value and comments
- string mySentry; // optional string to signal end of file
- std::map<string,string> myContents; // extracted keys and values
-
- typedef std::map<string,string>::iterator mapi;
- typedef std::map<string,string>::const_iterator mapci;
-
- // Methods
- public:
- ConfigFile( string filename,
- string delimiter = "=",
- string comment = "#",
- string sentry = "EndConfigFile" );
- ConfigFile();
-
- // Search for key and read value or optional default value
- template<class T> T read( const string& key ) const; // call as read<T>
- template<class T> T read( const string& key, const T& value ) const;
- template<class T> bool readInto( T& var, const string& key ) const;
- template<class T>
- bool readInto( T& var, const string& key, const T& value ) const;
-
- // Modify keys and values
- template<class T> void add( string key, const T& value );
- void remove( const string& key );
-
- // Check whether key exists in configuration
- bool keyExists( const string& key ) const;
-
- // Check or change configuration syntax
- string getDelimiter() const { return myDelimiter; }
- string getComment() const { return myComment; }
- string getSentry() const { return mySentry; }
- string setDelimiter( const string& s )
- { string old = myDelimiter; myDelimiter = s; return old; }
- string setComment( const string& s )
- { string old = myComment; myComment = s; return old; }
-
- // Write or read configuration
- friend std::ostream& operator<<( std::ostream& os, const ConfigFile& cf );
- friend std::istream& operator>>( std::istream& is, ConfigFile& cf );
-
- protected:
- template<class T> static string T_as_string( const T& t );
- template<class T> static T string_as_T( const string& s );
- static void trim( string& s );
-
-
- // Exception types
- public:
- struct file_not_found {
- string filename;
- file_not_found( const string& filename_ = string() )
- : filename(filename_) {} };
- struct key_not_found { // thrown only by T read(key) variant of read()
- string key;
- key_not_found( const string& key_ = string() )
- : key(key_) {} };
- };
-
-
- /* static */
- template<class T>
- string ConfigFile::T_as_string( const T& t )
- {
- // Convert from a T to a string
- // Type T must support << operator
- std::ostringstream ost;
- ost << t;
- return ost.str();
- }
-
-
- /* static */
- template<class T>
- T ConfigFile::string_as_T( const string& s )
- {
- // Convert from a string to a T
- // Type T must support >> operator
- T t;
- std::istringstream ist(s);
- ist >> t;
- return t;
- }
-
-
- /* static */
- template<>
- inline string ConfigFile::string_as_T<string>( const string& s )
- {
- // Convert from a string to a string
- // In other words, do nothing
- return s;
- }
-
-
- /* static */
- template<>
- inline bool ConfigFile::string_as_T<bool>( const string& s )
- {
- // Convert from a string to a bool
- // Interpret "false", "F", "no", "n", "0" as false
- // Interpret "true", "T", "yes", "y", "1", "-1", or anything else as true
- bool b = true;
- string sup = s;
- for( string::iterator p = sup.begin(); p != sup.end(); ++p )
- *p = toupper(*p); // make string all caps
- if( sup==string("FALSE") || sup==string("F") ||
- sup==string("NO") || sup==string("N") ||
- sup==string("0") || sup==string("NONE") )
- b = false;
- return b;
- }
-
-
- template<class T>
- T ConfigFile::read( const string& key ) const
- {
- // Read the value corresponding to key
- mapci p = myContents.find(key);
- if( p == myContents.end() ) throw key_not_found(key);
- return string_as_T<T>( p->second );
- }
-
-
- template<class T>
- T ConfigFile::read( const string& key, const T& value ) const
- {
- // Return the value corresponding to key or given default value
- // if key is not found
- mapci p = myContents.find(key);
- if( p == myContents.end() ) return value;
- return string_as_T<T>( p->second );
- }
-
-
- template<class T>
- bool ConfigFile::readInto( T& var, const string& key ) const
- {
- // Get the value corresponding to key and store in var
- // Return true if key is found
- // Otherwise leave var untouched
- mapci p = myContents.find(key);
- bool found = ( p != myContents.end() );
- if( found ) var = string_as_T<T>( p->second );
- return found;
- }
-
-
- template<class T>
- bool ConfigFile::readInto( T& var, const string& key, const T& value ) const
- {
- // Get the value corresponding to key and store in var
- // Return true if key is found
- // Otherwise set var to given default
- mapci p = myContents.find(key);
- bool found = ( p != myContents.end() );
- if( found )
- var = string_as_T<T>( p->second );
- else
- var = value;
- return found;
- }
-
-
- template<class T>
- void ConfigFile::add( string key, const T& value )
- {
- // Add a key with given value
- string v = T_as_string( value );
- trim(key);
- trim(v);
- myContents[key] = v;
- return;
- }
-
- #endif // CONFIGFILE_H
-
- // Release notes:
- // v1.0 21 May 1999
- // + First release
- // + Template read() access only through non-member readConfigFile()
- // + ConfigurationFileBool is only built-in helper class
- //
- // v2.0 3 May 2002
- // + Shortened name from ConfigurationFile to ConfigFile
- // + Implemented template member functions
- // + Changed default comment separator from % to #
- // + Enabled reading of multiple-line values
- //
- // v2.1 24 May 2004
- // + Made template specializations inline to avoid compiler-dependent linkage
- // + Allowed comments within multiple-line values
- // + Enabled blank line termination for multiple-line values
- // + Added optional sentry to detect end of configuration file
- // + Rewrote messy trimWhitespace() function as elegant trim()
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