C++ Options::GetDefinitions方法代码示例

void
Args::ParseArgsForCompletion
(
    Options &options,
    OptionElementVector &option_element_vector,
    uint32_t cursor_index
)
{
    StreamString sstr;
    struct option *long_options = options.GetLongOptions();
    option_element_vector.clear();

    if (long_options == NULL)
    {
        return;
    }

    // Leading : tells getopt to return a : for a missing option argument AND
    // to suppress error messages.

    sstr << ":";
    for (int i = 0; long_options[i].name != NULL; ++i)
    {
        if (long_options[i].flag == NULL)
        {
            sstr << (char) long_options[i].val;
            switch (long_options[i].has_arg)
            {
                default:
                case no_argument:
                    break;
                case required_argument:
                    sstr << ":";
                    break;
                case optional_argument:
                    sstr << "::";
                    break;
            }
        }
    }

#ifdef __GLIBC__
    optind = 0;
#else
    optreset = 1;
    optind = 1;
#endif
    opterr = 0;

    int val;
    const OptionDefinition *opt_defs = options.GetDefinitions();

    // Fooey... getopt_long permutes the GetArgumentVector to move the options to the front.
    // So we have to build another Arg and pass that to getopt_long so it doesn't
    // change the one we have.

    std::vector<const char *> dummy_vec (GetArgumentVector(), GetArgumentVector() + GetArgumentCount() + 1);

    bool failed_once = false;
    uint32_t dash_dash_pos = -1;
        
    while (1)
    {
        bool missing_argument = false;
        int parse_start = optind;
        int long_options_index = -1;
        
        val = ::getopt_long (dummy_vec.size() - 1,
                             (char *const *) dummy_vec.data(), 
                             sstr.GetData(), 
                             long_options,
                             &long_options_index);

        if (val == -1)
        {
            // When we're completing a "--" which is the last option on line, 
            if (failed_once)
                break;
                
            failed_once = true;
            
            // If this is a bare  "--" we mark it as such so we can complete it successfully later.
            // Handling the "--" is a little tricky, since that may mean end of options or arguments, or the
            // user might want to complete options by long name.  I make this work by checking whether the
            // cursor is in the "--" argument, and if so I assume we're completing the long option, otherwise
            // I let it pass to getopt_long which will terminate the option parsing.
            // Note, in either case we continue parsing the line so we can figure out what other options
            // were passed.  This will be useful when we come to restricting completions based on what other
            // options we've seen on the line.

            if (optind < dummy_vec.size() - 1 
                && (strcmp (dummy_vec[optind-1], "--") == 0))
            {
                dash_dash_pos = optind - 1;
                if (optind - 1 == cursor_index)
                {
                    option_element_vector.push_back (OptionArgElement (OptionArgElement::eBareDoubleDash, optind - 1, 
                                                                   OptionArgElement::eBareDoubleDash));
                    continue;
                }
//.........这里部分代码省略.........