1// Copyright Vladimir Prus 2002-2004.
2// Distributed under the Boost Software License, Version 1.0.
3// (See accompanying file LICENSE_1_0.txt
4// or copy at http://www.boost.org/LICENSE_1_0.txt)
5
6
7#ifndef BOOST_CONFIG_FILE_VP_2003_01_02
8#define BOOST_CONFIG_FILE_VP_2003_01_02
9
10#include <iosfwd>
11#include <string>
12#include <set>
13
14#include <boost/noncopyable.hpp>
15#include <boost/program_options/config.hpp>
16#include <boost/program_options/option.hpp>
17#include <boost/program_options/eof_iterator.hpp>
18
19#include <boost/detail/workaround.hpp>
20#include <boost/program_options/detail/convert.hpp>
21
22#if BOOST_WORKAROUND(__DECCXX_VER, BOOST_TESTED_AT(60590042))
23#include <istream> // std::getline
24#endif
25
26#include <boost/static_assert.hpp>
27#include <boost/type_traits/is_same.hpp>
28#include <boost/shared_ptr.hpp>
29
30#ifdef BOOST_MSVC
31# pragma warning(push)
32# pragma warning(disable: 4251) // class XYZ needs to have dll-interface to be used by clients of class XYZ
33#endif
34
35
36
37namespace boost { namespace program_options { namespace detail {
38
39 /** Standalone parser for config files in ini-line format.
40 The parser is a model of single-pass lvalue iterator, and
41 default constructor creates past-the-end-iterator. The typical usage is:
42 config_file_iterator i(is, ... set of options ...), e;
43 for(; i !=e; ++i) {
44 *i;
45 }
46
47 Syntax conventions:
48
49 - config file can not contain positional options
50 - '#' is comment character: it is ignored together with
51 the rest of the line.
52 - variable assignments are in the form
53 name '=' value.
54 spaces around '=' are trimmed.
55 - Section names are given in brackets.
56
57 The actual option name is constructed by combining current section
58 name and specified option name, with dot between. If section_name
59 already contains dot at the end, new dot is not inserted. For example:
60 @verbatim
61 [gui.accessibility]
62 visual_bell=yes
63 @endverbatim
64 will result in option "gui.accessibility.visual_bell" with value
65 "yes" been returned.
66
67 TODO: maybe, we should just accept a pointer to options_description
68 class.
69 */
70 class BOOST_PROGRAM_OPTIONS_DECL common_config_file_iterator
71 : public eof_iterator<common_config_file_iterator, option>
72 {
73 public:
74 common_config_file_iterator() { found_eof(); }
75 common_config_file_iterator(
76 const std::set<std::string>& allowed_options,
77 bool allow_unregistered = false);
78
79 BOOST_DEFAULTED_FUNCTION(virtual ~common_config_file_iterator(), {})
80
81 public: // Method required by eof_iterator
82
83 void get();
84
85#if BOOST_WORKAROUND(_MSC_VER, <= 1900)
86 void decrement() {}
87 void advance(difference_type) {}
88#endif
89
90 protected: // Stubs for derived classes
91
92 // Obtains next line from the config file
93 // Note: really, this design is a bit ugly
94 // The most clean thing would be to pass 'line_iterator' to
95 // constructor of this class, but to avoid templating this class
96 // we'd need polymorphic iterator, which does not exist yet.
97 virtual bool getline(std::string&) { return false; }
98
99 private:
100 /** Adds another allowed option. If the 'name' ends with
101 '*', then all options with the same prefix are
102 allowed. For example, if 'name' is 'foo*', then 'foo1' and
103 'foo_bar' are allowed. */
104 void add_option(const char* name);
105
106 // Returns true if 's' is a registered option name.
107 bool allowed_option(const std::string& s) const;
108
109 // That's probably too much data for iterator, since
110 // it will be copied, but let's not bother for now.
111 std::set<std::string> allowed_options;
112 // Invariant: no element is prefix of other element.
113 std::set<std::string> allowed_prefixes;
114 std::string m_prefix;
115 bool m_allow_unregistered;
116 };
117
118 template<class charT>
119 class basic_config_file_iterator : public common_config_file_iterator {
120 public:
121 basic_config_file_iterator()
122 {
123 found_eof();
124 }
125
126 /** Creates a config file parser for the specified stream.
127 */
128 basic_config_file_iterator(std::basic_istream<charT>& is,
129 const std::set<std::string>& allowed_options,
130 bool allow_unregistered = false);
131
132 private: // base overrides
133
134 bool getline(std::string&);
135
136 private: // internal data
137 shared_ptr<std::basic_istream<charT> > is;
138 };
139
140 typedef basic_config_file_iterator<char> config_file_iterator;
141 typedef basic_config_file_iterator<wchar_t> wconfig_file_iterator;
142
143
144 struct null_deleter
145 {
146 void operator()(void const *) const {}
147 };
148
149
150 template<class charT>
151 basic_config_file_iterator<charT>::
152 basic_config_file_iterator(std::basic_istream<charT>& is,
153 const std::set<std::string>& allowed_options,
154 bool allow_unregistered)
155 : common_config_file_iterator(allowed_options, allow_unregistered)
156 {
157 this->is.reset(&is, null_deleter());
158 get();
159 }
160
161 // Specializing this function for wchar_t causes problems on
162 // borland and vc7, as well as on metrowerks. On the first two
163 // I don't know a workaround, so make use of 'to_internal' to
164 // avoid specialization.
165 template<class charT>
166 bool
167 basic_config_file_iterator<charT>::getline(std::string& s)
168 {
169 std::basic_string<charT> in;
170 if (std::getline(*is, in)) {
171 s = to_internal(in);
172 return true;
173 } else {
174 return false;
175 }
176 }
177
178 // Specialization is needed to workaround getline bug on Comeau.
179#if BOOST_WORKAROUND(__COMO_VERSION__, BOOST_TESTED_AT(4303)) || \
180 (defined(__sgi) && BOOST_WORKAROUND(_COMPILER_VERSION, BOOST_TESTED_AT(741)))
181 template<>
182 bool
183 basic_config_file_iterator<wchar_t>::getline(std::string& s);
184#endif
185
186
187
188}}}
189
190#ifdef BOOST_MSVC
191# pragma warning(pop)
192#endif
193
194#endif
195

source code of boost/libs/program_options/include/boost/program_options/detail/config_file.hpp