1 // ConfigFile.cpp
2
3 #include "ConfigFile.h"
4
5 using std::string;
6
ConfigFile(string filename,string delimiter,string comment,string sentry)7 ConfigFile::ConfigFile( string filename, string delimiter,
8 string comment, string sentry )
9 : myDelimiter(delimiter), myComment(comment), mySentry(sentry)
10 {
11 // Construct a ConfigFile, getting keys and values from given file
12
13 std::ifstream in( filename.c_str() );
14
15 if( !in ) throw file_not_found( filename );
16
17 in >> (*this);
18 }
19
20
ConfigFile()21 ConfigFile::ConfigFile()
22 : myDelimiter( string(1,'=') ), myComment( string(1,'#') )
23 {
24 // Construct a ConfigFile without a file; empty
25 }
26
27
remove(const string & key)28 void ConfigFile::remove( const string& key )
29 {
30 // Remove key and its value
31 myContents.erase( myContents.find( key ) );
32 return;
33 }
34
35
keyExists(const string & key) const36 bool ConfigFile::keyExists( const string& key ) const
37 {
38 // Indicate whether key is found
39 mapci p = myContents.find( key );
40 return ( p != myContents.end() );
41 }
42
43
44 /* static */
trim(string & s)45 void ConfigFile::trim( string& s )
46 {
47 // Remove leading and trailing whitespace
48 static const char whitespace[] = " \n\t\v\r\f";
49 s.erase( 0, s.find_first_not_of(whitespace) );
50 s.erase( s.find_last_not_of(whitespace) + 1U );
51 }
52
53
operator <<(std::ostream & os,const ConfigFile & cf)54 std::ostream& operator<<( std::ostream& os, const ConfigFile& cf )
55 {
56 // Save a ConfigFile to os
57 for( ConfigFile::mapci p = cf.myContents.begin();
58 p != cf.myContents.end();
59 ++p )
60 {
61 os << p->first << " " << cf.myDelimiter << " ";
62 os << p->second << std::endl;
63 }
64 return os;
65 }
66
67
operator >>(std::istream & is,ConfigFile & cf)68 std::istream& operator>>( std::istream& is, ConfigFile& cf )
69 {
70 // Load a ConfigFile from is
71 // Read in keys and values, keeping internal whitespace
72 typedef string::size_type pos;
73 const string& delim = cf.myDelimiter; // separator
74 const string& comm = cf.myComment; // comment
75 const string& sentry = cf.mySentry; // end of file sentry
76 const pos skip = delim.length(); // length of separator
77
78 string nextline = ""; // might need to read ahead to see where value ends
79
80 while( is || nextline.length() > 0 )
81 {
82 // Read an entire line at a time
83 string line;
84 if( nextline.length() > 0 )
85 {
86 line = nextline; // we read ahead; use it now
87 nextline = "";
88 }
89 else
90 {
91 std::getline( is, line );
92 }
93
94 // Ignore comments
95 line = line.substr( 0, line.find(comm) );
96
97 // Check for end of file sentry
98 if( sentry != "" && line.find(sentry) != string::npos ) return is;
99
100 // Parse the line if it contains a delimiter
101 pos delimPos = line.find( delim );
102 if( delimPos < string::npos )
103 {
104 // Extract the key
105 string key = line.substr( 0, delimPos );
106 line.replace( 0, delimPos+skip, "" );
107
108 // See if value continues on the next line
109 // Stop at blank line, next line with a key, end of stream,
110 // or end of file sentry
111 bool terminate = false;
112 while( !terminate && is )
113 {
114 std::getline( is, nextline );
115 terminate = true;
116
117 string nlcopy = nextline;
118 ConfigFile::trim(nlcopy);
119 if( nlcopy == "" ) continue;
120
121 nextline = nextline.substr( 0, nextline.find(comm) );
122 if( nextline.find(delim) != string::npos )
123 continue;
124 if( sentry != "" && nextline.find(sentry) != string::npos )
125 continue;
126
127 nlcopy = nextline;
128 ConfigFile::trim(nlcopy);
129 if( nlcopy != "" ) line += "\n";
130 line += nextline;
131 terminate = false;
132 }
133
134 // Store key and value
135 ConfigFile::trim(key);
136 ConfigFile::trim(line);
137 cf.myContents[key] = line; // overwrites if key is repeated
138 }
139 }
140
141 return is;
142 }
143