1 /*
2 *
3 * Copyright (c) 1998-2002
4 * John Maddock
5 *
6 * Use, modification and distribution are subject to the
7 * Boost Software License, Version 1.0. (See accompanying file
8 * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
9 *
10 */
11
12 /*
13 * LOCATION: see http://www.boost.org for most recent version.
14 * FILE regex_grep_example_1.cpp
15 * VERSION see <boost/version.hpp>
16 * DESCRIPTION: regex_grep example 1: searches a cpp file for class definitions.
17 */
18
19 #include <boost/regex.hpp>
20 #include <string>
21 #include <map>
22
23 // purpose:
24 // takes the contents of a file in the form of a string
25 // and searches for all the C++ class definitions, storing
26 // their locations in a map of strings/int's
27
28 typedef std::map<std::string, std::string::difference_type, std::less<std::string> > map_type;
29
30 const char* re =
31 // possibly leading whitespace:
32 "^[[:space:]]*"
33 // possible template declaration:
34 "(template[[:space:]]*<[^;:{]+>[[:space:]]*)?"
35 // class or struct:
36 "(class|struct)[[:space:]]*"
37 // leading declspec macros etc:
38 "("
39 "\\<\\w+\\>"
40 "("
41 "[[:blank:]]*\\([^)]*\\)"
42 ")?"
43 "[[:space:]]*"
44 ")*"
45 // the class name
46 "(\\<\\w*\\>)[[:space:]]*"
47 // template specialisation parameters
48 "(<[^;:{]+>)?[[:space:]]*"
49 // terminate in { or :
50 "(\\{|:[^;\\{()]*\\{)";
51
52 boost::regex expression(re);
53
54 class IndexClassesPred
55 {
56 map_type& m;
57 std::string::const_iterator base;
58 public:
IndexClassesPred(map_type & a,std::string::const_iterator b)59 IndexClassesPred(map_type& a, std::string::const_iterator b) : m(a), base(b) {}
operator ()(const boost::match_results<std::string::const_iterator> & what)60 bool operator()(const boost::match_results<std::string::const_iterator>& what)
61 {
62 // what[0] contains the whole string
63 // what[5] contains the class name.
64 // what[6] contains the template specialisation if any.
65 // add class name and position to map:
66 m[std::string(what[5].first, what[5].second) + std::string(what[6].first, what[6].second)] =
67 what[5].first - base;
68 return true;
69 }
70 private:
71 IndexClassesPred& operator=(const IndexClassesPred&);
72 };
73
IndexClasses(map_type & m,const std::string & file)74 void IndexClasses(map_type& m, const std::string& file)
75 {
76 std::string::const_iterator start, end;
77 start = file.begin();
78 end = file.end();
79 boost::regex_grep(IndexClassesPred(m, start), start, end, expression);
80 }
81
82
83 #include <fstream>
84 #include <iostream>
85
86 using namespace std;
87
load_file(std::string & s,std::istream & is)88 void load_file(std::string& s, std::istream& is)
89 {
90 s.erase();
91 if(is.bad()) return;
92 s.reserve(static_cast<std::string::size_type>(is.rdbuf()->in_avail()));
93 char c;
94 while(is.get(c))
95 {
96 if(s.capacity() == s.size())
97 s.reserve(s.capacity() * 3);
98 s.append(1, c);
99 }
100 }
101
main(int argc,const char ** argv)102 int main(int argc, const char** argv)
103 {
104 std::string text;
105 for(int i = 1; i < argc; ++i)
106 {
107 cout << "Processing file " << argv[i] << endl;
108 map_type m;
109 std::ifstream fs(argv[i]);
110 load_file(text, fs);
111 fs.close();
112 IndexClasses(m, text);
113 cout << m.size() << " matches found" << endl;
114 map_type::iterator c, d;
115 c = m.begin();
116 d = m.end();
117 while(c != d)
118 {
119 cout << "class \"" << (*c).first << "\" found at index: " << (*c).second << endl;
120 ++c;
121 }
122 }
123 return 0;
124 }
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