// Copyright Vladimir Prus 2002-2004. // Distributed under the Boost Software License, Version 1.0. // (See accompanying file LICENSE_1_0.txt // or copy at http://www.boost.org/LICENSE_1_0.txt) #ifndef BOOST_CONFIG_FILE_VP_2003_01_02 #define BOOST_CONFIG_FILE_VP_2003_01_02 #include <iosfwd> #include <string> #include <set> #include <boost/noncopyable.hpp> #include <boost/program_options/config.hpp> #include <boost/program_options/option.hpp> #include <boost/program_options/eof_iterator.hpp> #include <boost/detail/workaround.hpp> #if BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3202)) #include <boost/program_options/detail/convert.hpp> #endif #if BOOST_WORKAROUND(__DECCXX_VER, BOOST_TESTED_AT(60590042)) #include <istream> // std::getline #endif #include <boost/static_assert.hpp> #include <boost/type_traits/is_same.hpp> #include <boost/shared_ptr.hpp> namespace boost { namespace program_options { namespace detail { /** Standalone parser for config files in ini-line format. The parser is a model of single-pass lvalue iterator, and default constructor creates past-the-end-iterator. The typical usage is: config_file_iterator i(is, ... set of options ...), e; for(; i !=e; ++i) { *i; } Syntax conventions: - config file can not contain positional options - '#' is comment character: it is ignored together with the rest of the line. - variable assignments are in the form name '=' value. spaces around '=' are trimmed. - Section names are given in brackets. The actual option name is constructed by combining current section name and specified option name, with dot between. If section_name already contains dot at the end, new dot is not inserted. For example: @verbatim [gui.accessibility] visual_bell=yes @endverbatim will result in option "gui.accessibility.visual_bell" with value "yes" been returned. TODO: maybe, we should just accept a pointer to options_description class. */ class common_config_file_iterator : public eof_iterator<common_config_file_iterator, option> { public: common_config_file_iterator() { found_eof(); } common_config_file_iterator( const std::set<std::string>& allowed_options, bool allow_unregistered = false); virtual ~common_config_file_iterator() {} public: // Method required by eof_iterator void get(); protected: // Stubs for derived classes // Obtains next line from the config file // Note: really, this design is a bit ugly // The most clean thing would be to pass 'line_iterator' to // constructor of this class, but to avoid templating this class // we'd need polymorphic iterator, which does not exist yet. virtual bool getline(std::string&) { return false; } private: /** Adds another allowed option. If the 'name' ends with '*', then all options with the same prefix are allowed. For example, if 'name' is 'foo*', then 'foo1' and 'foo_bar' are allowed. */ void add_option(const char* name); // Returns true if 's' is a registered option name. bool allowed_option(const std::string& s) const; // That's probably too much data for iterator, since // it will be copied, but let's not bother for now. std::set<std::string> allowed_options; // Invariant: no element is prefix of other element. std::set<std::string> allowed_prefixes; std::string m_prefix; bool m_allow_unregistered; }; template<class charT> class basic_config_file_iterator : public common_config_file_iterator { public: basic_config_file_iterator() { found_eof(); } /** Creates a config file parser for the specified stream. */ basic_config_file_iterator(std::basic_istream<charT>& is, const std::set<std::string>& allowed_options, bool allow_unregistered = false); private: // base overrides bool getline(std::string&); private: // internal data shared_ptr<std::basic_istream<charT> > is; }; typedef basic_config_file_iterator<char> config_file_iterator; typedef basic_config_file_iterator<wchar_t> wconfig_file_iterator; struct null_deleter { void operator()(void const *) const {} }; template<class charT> basic_config_file_iterator<charT>:: basic_config_file_iterator(std::basic_istream<charT>& is, const std::set<std::string>& allowed_options, bool allow_unregistered) : common_config_file_iterator(allowed_options, allow_unregistered) { this->is.reset(&is, null_deleter()); get(); } // Specializing this function for wchar_t causes problems on // borland and vc7, as well as on metrowerks. On the first two // I don't know a workaround, so make use of 'to_internal' to // avoid specialization. template<class charT> bool basic_config_file_iterator<charT>::getline(std::string& s) { std::basic_string<charT> in; if (std::getline(*is, in)) { s = to_internal(in); return true; } else { return false; } } // Specialization is needed to workaround getline bug on Comeau. #if BOOST_WORKAROUND(__COMO_VERSION__, BOOST_TESTED_AT(4303)) || \ (defined(__sgi) && BOOST_WORKAROUND(_COMPILER_VERSION, BOOST_TESTED_AT(741))) template<> bool basic_config_file_iterator<wchar_t>::getline(std::string& s); #endif }}} #endif