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 #if BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3202)) 21 #include <boost/program_options/detail/convert.hpp> 22 #endif 23 24 #if BOOST_WORKAROUND(__DECCXX_VER, BOOST_TESTED_AT(60590042)) 25 #include <istream> // std::getline 26 #endif 27 28 #include <boost/static_assert.hpp> 29 #include <boost/type_traits/is_same.hpp> 30 #include <boost/shared_ptr.hpp> 31 32 33 34 namespace boost { namespace program_options { namespace detail { 35 36 /** Standalone parser for config files in ini-line format. 37 The parser is a model of single-pass lvalue iterator, and 38 default constructor creates past-the-end-iterator. The typical usage is: 39 config_file_iterator i(is, ... set of options ...), e; 40 for(; i !=e; ++i) { 41 *i; 42 } 43 44 Syntax conventions: 45 46 - config file can not contain positional options 47 - '#' is comment character: it is ignored together with 48 the rest of the line. 49 - variable assignments are in the form 50 name '=' value. 51 spaces around '=' are trimmed. 52 - Section names are given in brackets. 53 54 The actual option name is constructed by combining current section 55 name and specified option name, with dot between. If section_name 56 already contains dot at the end, new dot is not inserted. For example: 57 @verbatim 58 [gui.accessibility] 59 visual_bell=yes 60 @endverbatim 61 will result in option "gui.accessibility.visual_bell" with value 62 "yes" been returned. 63 64 TODO: maybe, we should just accept a pointer to options_description 65 class. 66 */ 67 class common_config_file_iterator 68 : public eof_iterator<common_config_file_iterator, option> 69 { 70 public: common_config_file_iterator()71 common_config_file_iterator() { found_eof(); } 72 common_config_file_iterator( 73 const std::set<std::string>& allowed_options); 74 ~common_config_file_iterator()75 virtual ~common_config_file_iterator() {} 76 77 public: // Method required by eof_iterator 78 79 void get(); 80 81 protected: // Stubs for derived classes 82 83 // Obtains next line from the config file 84 // Note: really, this design is a bit ugly 85 // The most clean thing would be to pass 'line_iterator' to 86 // constructor of this class, but to avoid templating this class 87 // we'd need polymorphic iterator, which does not exist yet. getline(std::string &)88 virtual bool getline(std::string&) { return false; } 89 90 private: 91 /** Adds another allowed option. If the 'name' ends with 92 '*', then all options with the same prefix are 93 allowed. For example, if 'name' is 'foo*', then 'foo1' and 94 'foo_bar' are allowed. */ 95 void add_option(const char* name); 96 97 // Returns true if 's' is a registered option name. 98 bool allowed_option(const std::string& s) const; 99 100 // That's probably too much data for iterator, since 101 // it will be copied, but let's not bother for now. 102 std::set<std::string> allowed_options; 103 // Invariant: no element is prefix of other element. 104 std::set<std::string> allowed_prefixes; 105 std::string m_prefix; 106 }; 107 108 template<class charT> 109 class basic_config_file_iterator : public common_config_file_iterator { 110 public: basic_config_file_iterator()111 basic_config_file_iterator() 112 { 113 found_eof(); 114 } 115 116 /** Creates a config file parser for the specified stream. 117 */ 118 basic_config_file_iterator(std::basic_istream<charT>& is, 119 const std::set<std::string>& allowed_options); 120 121 private: // base overrides 122 123 bool getline(std::string&); 124 125 private: // internal data 126 shared_ptr<std::basic_istream<charT> > is; 127 }; 128 129 typedef basic_config_file_iterator<char> config_file_iterator; 130 typedef basic_config_file_iterator<wchar_t> wconfig_file_iterator; 131 132 133 struct null_deleter 134 { operator ()boost::program_options::detail::null_deleter135 void operator()(void const *) const {} 136 }; 137 138 139 template<class charT> 140 basic_config_file_iterator<charT>:: basic_config_file_iterator(std::basic_istream<charT> & is,const std::set<std::string> & allowed_options)141 basic_config_file_iterator(std::basic_istream<charT>& is, 142 const std::set<std::string>& allowed_options) 143 : common_config_file_iterator(allowed_options) 144 { 145 this->is.reset(&is, null_deleter()); 146 get(); 147 } 148 149 // Specializing this function for wchar_t causes problems on 150 // borland and vc7, as well as on metrowerks. On the first two 151 // I don't know a workaround, so make use of 'to_internal' to 152 // avoid specialization. 153 template<class charT> 154 bool getline(std::string & s)155 basic_config_file_iterator<charT>::getline(std::string& s) 156 { 157 std::basic_string<charT> in; 158 if (std::getline(*is, in)) { 159 s = to_internal(in); 160 return true; 161 } else { 162 return false; 163 } 164 } 165 166 // Specialization is needed to workaround getline bug on Comeau. 167 #if BOOST_WORKAROUND(__COMO_VERSION__, BOOST_TESTED_AT(4303)) || \ 168 (defined(__sgi) && BOOST_WORKAROUND(_COMPILER_VERSION, BOOST_TESTED_AT(741))) 169 template<> 170 bool 171 basic_config_file_iterator<wchar_t>::getline(std::string& s); 172 #endif 173 174 175 176 }}} 177 178 #endif 179