bool sax_parse_internal()

in impl/build/include/headers/json/json.hpp [10828:11099]


    bool sax_parse_internal(SAX* sax)
    {
        // stack to remember the hierarchy of structured values we are parsing
        // true = array; false = object
        std::vector<bool> states;
        // value to avoid a goto (see comment where set to true)
        bool skip_to_state_evaluation = false;

        while (true)
        {
            if (!skip_to_state_evaluation)
            {
                // invariant: get_token() was called before each iteration
                switch (last_token)
                {
                    case token_type::begin_object:
                    {
                        if (JSON_HEDLEY_UNLIKELY(!sax->start_object(std::size_t(-1))))
                        {
                            return false;
                        }

                        // closing } -> we are done
                        if (get_token() == token_type::end_object)
                        {
                            if (JSON_HEDLEY_UNLIKELY(!sax->end_object()))
                            {
                                return false;
                            }
                            break;
                        }

                        // parse key
                        if (JSON_HEDLEY_UNLIKELY(last_token != token_type::value_string))
                        {
                            return sax->parse_error(m_lexer.get_position(),
                                                    m_lexer.get_token_string(),
                                                    parse_error::create(101, m_lexer.get_position(), exception_message(token_type::value_string, "object key"), BasicJsonType()));
                        }
                        if (JSON_HEDLEY_UNLIKELY(!sax->key(m_lexer.get_string())))
                        {
                            return false;
                        }

                        // parse separator (:)
                        if (JSON_HEDLEY_UNLIKELY(get_token() != token_type::name_separator))
                        {
                            return sax->parse_error(m_lexer.get_position(),
                                                    m_lexer.get_token_string(),
                                                    parse_error::create(101, m_lexer.get_position(), exception_message(token_type::name_separator, "object separator"), BasicJsonType()));
                        }

                        // remember we are now inside an object
                        states.push_back(false);

                        // parse values
                        get_token();
                        continue;
                    }

                    case token_type::begin_array:
                    {
                        if (JSON_HEDLEY_UNLIKELY(!sax->start_array(std::size_t(-1))))
                        {
                            return false;
                        }

                        // closing ] -> we are done
                        if (get_token() == token_type::end_array)
                        {
                            if (JSON_HEDLEY_UNLIKELY(!sax->end_array()))
                            {
                                return false;
                            }
                            break;
                        }

                        // remember we are now inside an array
                        states.push_back(true);

                        // parse values (no need to call get_token)
                        continue;
                    }

                    case token_type::value_float:
                    {
                        const auto res = m_lexer.get_number_float();

                        if (JSON_HEDLEY_UNLIKELY(!std::isfinite(res)))
                        {
                            return sax->parse_error(m_lexer.get_position(),
                                                    m_lexer.get_token_string(),
                                                    out_of_range::create(406, "number overflow parsing '" + m_lexer.get_token_string() + "'", BasicJsonType()));
                        }

                        if (JSON_HEDLEY_UNLIKELY(!sax->number_float(res, m_lexer.get_string())))
                        {
                            return false;
                        }

                        break;
                    }

                    case token_type::literal_false:
                    {
                        if (JSON_HEDLEY_UNLIKELY(!sax->boolean(false)))
                        {
                            return false;
                        }
                        break;
                    }

                    case token_type::literal_null:
                    {
                        if (JSON_HEDLEY_UNLIKELY(!sax->null()))
                        {
                            return false;
                        }
                        break;
                    }

                    case token_type::literal_true:
                    {
                        if (JSON_HEDLEY_UNLIKELY(!sax->boolean(true)))
                        {
                            return false;
                        }
                        break;
                    }

                    case token_type::value_integer:
                    {
                        if (JSON_HEDLEY_UNLIKELY(!sax->number_integer(m_lexer.get_number_integer())))
                        {
                            return false;
                        }
                        break;
                    }

                    case token_type::value_string:
                    {
                        if (JSON_HEDLEY_UNLIKELY(!sax->string(m_lexer.get_string())))
                        {
                            return false;
                        }
                        break;
                    }

                    case token_type::value_unsigned:
                    {
                        if (JSON_HEDLEY_UNLIKELY(!sax->number_unsigned(m_lexer.get_number_unsigned())))
                        {
                            return false;
                        }
                        break;
                    }

                    case token_type::parse_error:
                    {
                        // using "uninitialized" to avoid "expected" message
                        return sax->parse_error(m_lexer.get_position(),
                                                m_lexer.get_token_string(),
                                                parse_error::create(101, m_lexer.get_position(), exception_message(token_type::uninitialized, "value"), BasicJsonType()));
                    }

                    default: // the last token was unexpected
                    {
                        return sax->parse_error(m_lexer.get_position(),
                                                m_lexer.get_token_string(),
                                                parse_error::create(101, m_lexer.get_position(), exception_message(token_type::literal_or_value, "value"), BasicJsonType()));
                    }
                }
            }
            else
            {
                skip_to_state_evaluation = false;
            }

            // we reached this line after we successfully parsed a value
            if (states.empty())
            {
                // empty stack: we reached the end of the hierarchy: done
                return true;
            }

            if (states.back())  // array
            {
                // comma -> next value
                if (get_token() == token_type::value_separator)
                {
                    // parse a new value
                    get_token();
                    continue;
                }

                // closing ]
                if (JSON_HEDLEY_LIKELY(last_token == token_type::end_array))
                {
                    if (JSON_HEDLEY_UNLIKELY(!sax->end_array()))
                    {
                        return false;
                    }

                    // We are done with this array. Before we can parse a
                    // new value, we need to evaluate the new state first.
                    // By setting skip_to_state_evaluation to false, we
                    // are effectively jumping to the beginning of this if.
                    JSON_ASSERT(!states.empty());
                    states.pop_back();
                    skip_to_state_evaluation = true;
                    continue;
                }

                return sax->parse_error(m_lexer.get_position(),
                                        m_lexer.get_token_string(),
                                        parse_error::create(101, m_lexer.get_position(), exception_message(token_type::end_array, "array"), BasicJsonType()));
            }

            // states.back() is false -> object

            // comma -> next value
            if (get_token() == token_type::value_separator)
            {
                // parse key
                if (JSON_HEDLEY_UNLIKELY(get_token() != token_type::value_string))
                {
                    return sax->parse_error(m_lexer.get_position(),
                                            m_lexer.get_token_string(),
                                            parse_error::create(101, m_lexer.get_position(), exception_message(token_type::value_string, "object key"), BasicJsonType()));
                }

                if (JSON_HEDLEY_UNLIKELY(!sax->key(m_lexer.get_string())))
                {
                    return false;
                }

                // parse separator (:)
                if (JSON_HEDLEY_UNLIKELY(get_token() != token_type::name_separator))
                {
                    return sax->parse_error(m_lexer.get_position(),
                                            m_lexer.get_token_string(),
                                            parse_error::create(101, m_lexer.get_position(), exception_message(token_type::name_separator, "object separator"), BasicJsonType()));
                }

                // parse values
                get_token();
                continue;
            }

            // closing }
            if (JSON_HEDLEY_LIKELY(last_token == token_type::end_object))
            {
                if (JSON_HEDLEY_UNLIKELY(!sax->end_object()))
                {
                    return false;
                }

                // We are done with this object. Before we can parse a
                // new value, we need to evaluate the new state first.
                // By setting skip_to_state_evaluation to false, we
                // are effectively jumping to the beginning of this if.
                JSON_ASSERT(!states.empty());
                states.pop_back();
                skip_to_state_evaluation = true;
                continue;
            }

            return sax->parse_error(m_lexer.get_position(),
                                    m_lexer.get_token_string(),
                                    parse_error::create(101, m_lexer.get_position(), exception_message(token_type::end_object, "object"), BasicJsonType()));
        }
    }