C++ Args::Unshift方法代码示例

bool
CommandObject::ParseOptions
(
    Args& args,
    CommandReturnObject &result
)
{
    // See if the subclass has options?
    Options *options = GetOptions();
    if (options != NULL)
    {
        Error error;
        options->NotifyOptionParsingStarting();

        // ParseOptions calls getopt_long, which always skips the zero'th item in the array and starts at position 1,
        // so we need to push a dummy value into position zero.
        args.Unshift("dummy_string");
        error = args.ParseOptions (*options);

        // The "dummy_string" will have already been removed by ParseOptions,
        // so no need to remove it.

        if (error.Success())
            error = options->NotifyOptionParsingFinished();

        if (error.Success())
        {
            if (options->VerifyOptions (result))
                return true;
        }
        else
        {
            const char *error_cstr = error.AsCString();
            if (error_cstr)
            {
                // We got an error string, lets use that
                result.AppendError(error_cstr);
            }
            else
            {
                // No error string, output the usage information into result
                options->GenerateOptionUsage (result.GetErrorStream(), this);
            }
        }
        result.SetStatus (eReturnStatusFailed);
        return false;
    }
    return true;
}

void
CommandInterpreter::BuildAliasCommandArgs
(
    CommandObject *alias_cmd_obj,
    const char *alias_name,
    Args &cmd_args,
    CommandReturnObject &result
)
{
    OptionArgVectorSP option_arg_vector_sp = GetAliasOptions (alias_name);

    if (option_arg_vector_sp.get())
    {
        // Make sure that the alias name is the 0th element in cmd_args
        std::string alias_name_str = alias_name;
        if (alias_name_str.compare (cmd_args.GetArgumentAtIndex(0)) != 0)
            cmd_args.Unshift (alias_name);

        Args new_args (alias_cmd_obj->GetCommandName());
        if (new_args.GetArgumentCount() == 2)
            new_args.Shift();

        OptionArgVector *option_arg_vector = option_arg_vector_sp.get();
        int old_size = cmd_args.GetArgumentCount();
        int *used = (int *) malloc ((old_size + 1) * sizeof (int));

        memset (used, 0, (old_size + 1) * sizeof (int));
        used[0] = 1;

        for (int i = 0; i < option_arg_vector->size(); ++i)
        {
            OptionArgPair option_pair = (*option_arg_vector)[i];
            std::string option = option_pair.first;
            std::string value = option_pair.second;
            if (option.compare ("<argument>") == 0)
                new_args.AppendArgument (value.c_str());
            else
            {
                new_args.AppendArgument (option.c_str());
                if (value.compare ("<no-argument>") != 0)
                {
                    int index = GetOptionArgumentPosition (value.c_str());
                    if (index == 0)
                        // value was NOT a positional argument; must be a real value
                        new_args.AppendArgument (value.c_str());
                    else if (index >= cmd_args.GetArgumentCount())
                    {
                        result.AppendErrorWithFormat
                                    ("Not enough arguments provided; you need at least %d arguments to use this alias.\n",
                                     index);
                        result.SetStatus (eReturnStatusFailed);
                        return;
                    }
                    else
                    {
                        new_args.AppendArgument (cmd_args.GetArgumentAtIndex (index));
                        used[index] = 1;
                    }
                }
            }
        }

        for (int j = 0; j < cmd_args.GetArgumentCount(); ++j)
        {
            if (!used[j])
                new_args.AppendArgument (cmd_args.GetArgumentAtIndex (j));
        }

        cmd_args.Clear();
        cmd_args.SetArguments (new_args.GetArgumentCount(), (const char **) new_args.GetArgumentVector());
    }
    else
    {
        result.SetStatus (eReturnStatusSuccessFinishNoResult);
        // This alias was not created with any options; nothing further needs to be done.
        return;
    }

    result.SetStatus (eReturnStatusSuccessFinishNoResult);
    return;
}

int
CommandObject::HandleCompletion
(
    Args &input,
    int &cursor_index,
    int &cursor_char_position,
    int match_start_point,
    int max_return_elements,
    bool &word_complete,
    StringList &matches
)
{
    // Default implmentation of WantsCompletion() is !WantsRawCommandString().
    // Subclasses who want raw command string but desire, for example,
    // argument completion should override WantsCompletion() to return true,
    // instead.
    if (WantsRawCommandString() && !WantsCompletion())
    {
        // FIXME: Abstract telling the completion to insert the completion character.
        matches.Clear();
        return -1;
    }
    else
    {
        // Can we do anything generic with the options?
        Options *cur_options = GetOptions();
        CommandReturnObject result;
        OptionElementVector opt_element_vector;

        if (cur_options != NULL)
        {
            // Re-insert the dummy command name string which will have been
            // stripped off:
            input.Unshift ("dummy-string");
            cursor_index++;


            // I stick an element on the end of the input, because if the last element is
            // option that requires an argument, getopt_long will freak out.

            input.AppendArgument ("<FAKE-VALUE>");

            input.ParseArgsForCompletion (*cur_options, opt_element_vector, cursor_index);

            input.DeleteArgumentAtIndex(input.GetArgumentCount() - 1);

            bool handled_by_options;
            handled_by_options = cur_options->HandleOptionCompletion (input,
                                                                      opt_element_vector,
                                                                      cursor_index,
                                                                      cursor_char_position,
                                                                      match_start_point,
                                                                      max_return_elements,
                                                                      word_complete,
                                                                      matches);
            if (handled_by_options)
                return matches.GetSize();
        }

        // If we got here, the last word is not an option or an option argument.
        return HandleArgumentCompletion (input,
                                         cursor_index,
                                         cursor_char_position,
                                         opt_element_vector,
                                         match_start_point,
                                         max_return_elements,
                                         word_complete,
                                         matches);
    }
}