cmdline.cpp

C++的一个好库。。。现在很流行

        if (m_positional)
        {
            unsigned position = 0;
            for (unsigned i = 0; i < result.size(); ++i) {
                option& opt = result[i];
                if (opt.position_key != -1) {
                    if (position >= m_positional->max_total_count())
                    {
                        throw too_many_positional_options_error(
                            "too many positional options");
                    }
                    opt.string_key = m_positional->name_for_position(position);
                    ++position;
                }
            }
        }

        return result;
    }

    void
    cmdline::finish_option(option& opt,
                           vector<string>& other_tokens)
    {                                    
        if (opt.string_key.empty())
            return;

        // First check that the option is valid, and get its description.
        // TODO: case-sensitivity.
        const option_description* xd = 
            m_desc->find_nothrow(opt.string_key, (m_style & allow_guessing));

        if (!xd)
        {
            if (m_allow_unregistered) {
                opt.unregistered = true;
                return;
            } else {
                boost::throw_exception(unknown_option(opt.string_key));
            }                
        }
        const option_description& d = *xd;

        // Canonize the name
        opt.string_key = d.key(opt.string_key);

        // We check that the min/max number of tokens for the option
        // agrees with the number of tokens we have. The 'adjacent_value'
        // (the value in --foo=1) counts as a separate token, and if present
        // must be consumed. The following tokens on the command line may be
        // left unconsumed.

        // We don't check if those tokens look like option, or not!

        unsigned min_tokens = d.semantic()->min_tokens();
        unsigned max_tokens = d.semantic()->max_tokens();
        
        unsigned present_tokens = opt.value.size() + other_tokens.size();
        
        if (present_tokens >= min_tokens)
        {
            if (!opt.value.empty() && max_tokens == 0) {
                throw invalid_command_line_syntax(opt.string_key,
                    invalid_command_line_syntax::extra_parameter);                                                                
            }
            
            max_tokens -= opt.value.size();

            // Everything's OK, move the values to the result.            
            for(;!other_tokens.empty() && max_tokens--; ) {
                opt.value.push_back(other_tokens[0]);
                opt.original_tokens.push_back(other_tokens[0]);
                other_tokens.erase(other_tokens.begin());
            }
        }
        else
        {
            throw invalid_command_line_syntax(opt.string_key,
                invalid_command_line_syntax::missing_parameter); 

        }
    }

    std::vector<option> 
    cmdline::parse_long_option(std::vector<string>& args)
    {
        vector<option> result;
        const std::string& tok = args[0];
        if (tok.size() >= 3 && tok[0] == '-' && tok[1] == '-')
        {   
            string name, adjacent;

            string::size_type p = tok.find('=');
            if (p != tok.npos)
            {
                name = tok.substr(2, p-2);
                adjacent = tok.substr(p+1);
                if (adjacent.empty())
                    throw invalid_command_line_syntax(name,
                      invalid_command_line_syntax::empty_adjacent_parameter);
            }
            else
            {
                name = tok.substr(2);
            }
            option opt;
            opt.string_key = name;
            if (!adjacent.empty())
                opt.value.push_back(adjacent);
            opt.original_tokens.push_back(tok);
            result.push_back(opt);
            args.erase(args.begin());
        }
        return result;
    }


    std::vector<option> 
    cmdline::parse_short_option(std::vector<string>& args)
    {
        const std::string& tok = args[0];
        if (tok.size() >= 2 && tok[0] == '-' && tok[1] != '-')
        {   
            vector<option> result;

            string name = tok.substr(0,2);
            string adjacent = tok.substr(2);

            // Short options can be 'grouped', so that
            // "-d -a" becomes "-da". Loop, processing one
            // option at a time. We exit the loop when either
            // we've processed all the token, or when the remainder
            // of token is considered to be value, not further grouped
            // option.
            for(;;) {
                const option_description* d 
                    = m_desc->find_nothrow(name, false);

                // FIXME: check for 'allow_sticky'.
                if (d && (m_style & allow_sticky) &&
                    d->semantic()->max_tokens() == 0 && !adjacent.empty()) {
                    // 'adjacent' is in fact further option.
                    option opt;
                    opt.string_key = name;
                    result.push_back(opt);

                    if (adjacent.empty())
                    {
                        args.erase(args.begin());
                        break;
                    }

                    name = string("-") + adjacent[0];
                    adjacent.erase(adjacent.begin());
                } else {
                    
                    option opt;
                    opt.string_key = name;
                    opt.original_tokens.push_back(tok);
                    if (!adjacent.empty())
                        opt.value.push_back(adjacent);
                    result.push_back(opt);
                    args.erase(args.begin());                    
                    break;
                }
            }
            return result;
        }
        return std::vector<option>();
    }

    std::vector<option> 
    cmdline::parse_dos_option(std::vector<string>& args)
    {
        vector<option> result;
        const std::string& tok = args[0];
        if (tok.size() >= 2 && tok[0] == '/')
        {   
            string name = "-" + tok.substr(1,1);
            string adjacent = tok.substr(2);

            option opt;
            opt.string_key = name;
            if (!adjacent.empty())
                opt.value.push_back(adjacent);
            opt.original_tokens.push_back(tok);
            result.push_back(opt);
            args.erase(args.begin());
        }
        return result;
    }

    std::vector<option> 
    cmdline::parse_disguised_long_option(std::vector<string>& args)
    {
        const std::string& tok = args[0];
        if (tok.size() >= 2 && 
            ((tok[0] == '-' && tok[1] != '-') ||
             ((m_style & allow_slash_for_short) && tok[0] == '/')))            
        {
            if (m_desc->find_nothrow(tok.substr(1, tok.find('=')-1), 
                                     m_style & allow_guessing)) {
                args[0].insert(0, "-");
                if (args[0][1] == '/')
                    args[0][1] = '-';
                return parse_long_option(args);
            }
        }
        return vector<option>();
    }

    std::vector<option> 
    cmdline::parse_terminator(std::vector<std::string>& args)
    {
        vector<option> result;
        const std::string& tok = args[0];
        if (tok == "--")
        {
            for(unsigned i = 1; i < args.size(); ++i)
            {
                option opt;
                opt.value.push_back(args[i]);
                result.push_back(opt);
            }
            args.clear();
        }
        return result;
    }

    std::vector<option> 
    cmdline::handle_additional_parser(std::vector<std::string>& args)
    {
        vector<option> result;
        pair<string, string> r = m_additional_parser(args[0]);
        if (!r.first.empty()) {
            option next;
            next.string_key = r.first;
            next.value.push_back(r.second);
            result.push_back(next);
            args.erase(args.begin());
        }
        return result;
    }

    void 
    cmdline::set_additional_parser(additional_parser p)
    {
        m_additional_parser = p;
    }

    void 
    cmdline::extra_style_parser(style_parser s)
    {
        m_style_parser = s;
    }



}}}