Example #1
0
/**
 * Parse a max 3 digit long octal number from input string iterator.
 *
 * @return uint32_t - parsed octal number
 */
static uint32_t
re_parse_octal (re_parser_ctx_t *parser_ctx_p) /**< RegExp parser context */
{
  uint32_t number = 0;
  for (int index = 0;
       index < 3
       && parser_ctx_p->input_curr_p < parser_ctx_p->input_end_p
       && lit_char_is_octal_digit (*parser_ctx_p->input_curr_p);
       index++)
  {
    number = number * 8 + lit_char_hex_to_int (*parser_ctx_p->input_curr_p++);
  }

  return number;
} /* re_parse_octal */
Example #2
0
/**
 * Read the input pattern and parse the range of character class
 *
 * @return completion value
 *         Returned value must be freed with ecma_free_completion_value
 */
ecma_completion_value_t
re_parse_char_class (re_parser_ctx_t *parser_ctx_p, /**< number of classes */
                     re_char_class_callback append_char_class, /**< callback function,
                                                                *   which adds the char-ranges
                                                                *   to the bytecode */
                     void *re_ctx_p, /**< regexp compiler context */
                     re_token_t *out_token_p) /**< out: output token */
{
  re_token_type_t token_type = ((re_compiler_ctx_t *) re_ctx_p)->current_token.type;
  out_token_p->qmax = out_token_p->qmin = 1;
  uint32_t start = RE_CHAR_UNDEF;
  bool is_range = false;
  parser_ctx_p->num_of_classes = 0;

  if (lit_utf8_peek_prev (parser_ctx_p->input_curr_p) != LIT_CHAR_LEFT_SQUARE)
  {
    lit_utf8_decr (&parser_ctx_p->input_curr_p);
    lit_utf8_decr (&parser_ctx_p->input_curr_p);
  }

  do
  {
    if (parser_ctx_p->input_curr_p >= parser_ctx_p->input_end_p)
    {
      return ecma_raise_syntax_error ("invalid character class, end of string");
    }

    uint32_t ch = lit_utf8_read_next (&parser_ctx_p->input_curr_p);

    if (ch == LIT_CHAR_RIGHT_SQUARE)
    {
      if (start != RE_CHAR_UNDEF)
      {
        append_char_class (re_ctx_p, start, start);
      }
      break;
    }
    else if (ch == LIT_CHAR_MINUS)
    {
      if (parser_ctx_p->input_curr_p >= parser_ctx_p->input_end_p)
      {
        return ecma_raise_syntax_error ("invalid character class, end of string after '-'");
      }

      if (start != RE_CHAR_UNDEF
          && !is_range
          && *parser_ctx_p->input_curr_p != LIT_CHAR_RIGHT_SQUARE)
      {
        is_range = true;
        continue;
      }
    }
    else if (ch == LIT_CHAR_BACKSLASH)
    {
      if (parser_ctx_p->input_curr_p >= parser_ctx_p->input_end_p)
      {
        return ecma_raise_syntax_error ("invalid character class, end of string after '\\'");
      }

      ch = *parser_ctx_p->input_curr_p++;

      if (ch == LIT_CHAR_LOWERCASE_B)
      {
        ch = LIT_CHAR_BS;
      }
      else if (ch == LIT_CHAR_LOWERCASE_F)
      {
        ch = LIT_CHAR_FF;
      }
      else if (ch == LIT_CHAR_LOWERCASE_N)
      {
        ch = LIT_CHAR_LF;
      }
      else if (ch == LIT_CHAR_LOWERCASE_T)
      {
        ch = LIT_CHAR_TAB;
      }
      else if (ch == LIT_CHAR_LOWERCASE_R)
      {
        ch = LIT_CHAR_CR;
      }
      else if (ch == LIT_CHAR_LOWERCASE_V)
      {
        ch = LIT_CHAR_VTAB;
      }
      else if (ch == LIT_CHAR_LOWERCASE_C)
      {
        if (parser_ctx_p->input_curr_p < parser_ctx_p->input_end_p)
        {
          ch = *parser_ctx_p->input_curr_p;

          if ((ch >= LIT_CHAR_ASCII_UPPERCASE_LETTERS_BEGIN && ch <= LIT_CHAR_ASCII_UPPERCASE_LETTERS_END)
              || (ch >= LIT_CHAR_ASCII_LOWERCASE_LETTERS_BEGIN && ch <= LIT_CHAR_ASCII_LOWERCASE_LETTERS_END)
              || (ch >= LIT_CHAR_0 && ch <= LIT_CHAR_9))
          {
            /* See ECMA-262 v5, 15.10.2.10 (Point 3) */
            ch = (ch % 32);
            parser_ctx_p->input_curr_p++;
          }
          else
          {
            ch = LIT_CHAR_LOWERCASE_C;
          }
        }
      }
      else if (ch == LIT_CHAR_LOWERCASE_X)
      {
        lit_code_point_t code_point;

        if (!lit_read_code_point_from_hex (parser_ctx_p->input_curr_p, 2, &code_point))
        {
          return ecma_raise_syntax_error ("invalid character class, end of string after '\\x'");
        }

        parser_ctx_p->input_curr_p += 2;
        append_char_class (re_ctx_p, code_point, code_point);
      }
      else if (ch == LIT_CHAR_LOWERCASE_U)
      {
        lit_code_point_t code_point;

        if (!lit_read_code_point_from_hex (parser_ctx_p->input_curr_p, 4, &code_point))
        {
          return ecma_raise_syntax_error ("invalid character class, end of string after '\\u'");
        }

        parser_ctx_p->input_curr_p += 4;
        append_char_class (re_ctx_p, code_point, code_point);
      }
      else if (ch == LIT_CHAR_LOWERCASE_D)
      {
        /* See ECMA-262 v5, 15.10.2.12 */
        append_char_class (re_ctx_p, LIT_CHAR_ASCII_DIGITS_BEGIN, LIT_CHAR_ASCII_DIGITS_END);
        ch = RE_CHAR_UNDEF;
      }
      else if (ch == LIT_CHAR_UPPERCASE_D)
      {
        /* See ECMA-262 v5, 15.10.2.12 */
        append_char_class (re_ctx_p, LIT_CHAR_NULL, LIT_CHAR_ASCII_DIGITS_BEGIN - 1);
        append_char_class (re_ctx_p, LIT_CHAR_ASCII_DIGITS_END + 1, LIT_UTF16_CODE_UNIT_MAX);
        ch = RE_CHAR_UNDEF;
      }
      else if (ch == LIT_CHAR_LOWERCASE_S)
      {
        /* See ECMA-262 v5, 15.10.2.12 */
        append_char_class (re_ctx_p, LIT_CHAR_TAB, LIT_CHAR_CR);
        append_char_class (re_ctx_p, LIT_CHAR_SP, LIT_CHAR_SP);
        append_char_class (re_ctx_p, LIT_CHAR_NBSP, LIT_CHAR_NBSP);
        append_char_class (re_ctx_p, 0x1680UL, 0x1680UL); /* Ogham Space Mark */
        append_char_class (re_ctx_p, 0x180EUL, 0x180EUL); /* Mongolian Vowel Separator */
        append_char_class (re_ctx_p, 0x2000UL, 0x200AUL); /* En Quad - Hair Space */
        append_char_class (re_ctx_p, LIT_CHAR_LS, LIT_CHAR_PS);
        append_char_class (re_ctx_p, 0x202FUL, 0x202FUL); /* Narrow No-Break Space */
        append_char_class (re_ctx_p, 0x205FUL, 0x205FUL); /* Medium Mathematical Space */
        append_char_class (re_ctx_p, 0x3000UL, 0x3000UL); /* Ideographic Space */
        append_char_class (re_ctx_p, LIT_CHAR_BOM, LIT_CHAR_BOM);
        ch = RE_CHAR_UNDEF;
      }
      else if (ch == LIT_CHAR_UPPERCASE_S)
      {
        /* See ECMA-262 v5, 15.10.2.12 */
        append_char_class (re_ctx_p, LIT_CHAR_NULL, LIT_CHAR_TAB - 1);
        append_char_class (re_ctx_p, LIT_CHAR_CR + 1, LIT_CHAR_SP - 1);
        append_char_class (re_ctx_p, LIT_CHAR_SP + 1, LIT_CHAR_NBSP - 1);
        append_char_class (re_ctx_p, LIT_CHAR_NBSP + 1, 0x167FUL);
        append_char_class (re_ctx_p, 0x1681UL, 0x180DUL);
        append_char_class (re_ctx_p, 0x180FUL, 0x1FFFUL);
        append_char_class (re_ctx_p, 0x200BUL, LIT_CHAR_LS - 1);
        append_char_class (re_ctx_p, LIT_CHAR_PS + 1, 0x202EUL);
        append_char_class (re_ctx_p, 0x2030UL, 0x205EUL);
        append_char_class (re_ctx_p, 0x2060UL, 0x2FFFUL);
        append_char_class (re_ctx_p, 0x3001UL, LIT_CHAR_BOM - 1);
        append_char_class (re_ctx_p, LIT_CHAR_BOM + 1, LIT_UTF16_CODE_UNIT_MAX);
        ch = RE_CHAR_UNDEF;
      }
      else if (ch == LIT_CHAR_LOWERCASE_W)
      {
        /* See ECMA-262 v5, 15.10.2.12 */
        append_char_class (re_ctx_p, LIT_CHAR_0, LIT_CHAR_9);
        append_char_class (re_ctx_p, LIT_CHAR_UPPERCASE_A, LIT_CHAR_UPPERCASE_Z);
        append_char_class (re_ctx_p, LIT_CHAR_UNDERSCORE, LIT_CHAR_UNDERSCORE);
        append_char_class (re_ctx_p, LIT_CHAR_LOWERCASE_A, LIT_CHAR_LOWERCASE_Z);
        ch = RE_CHAR_UNDEF;
      }
      else if (ch == LIT_CHAR_UPPERCASE_W)
      {
        /* See ECMA-262 v5, 15.10.2.12 */
        append_char_class (re_ctx_p, LIT_CHAR_NULL, LIT_CHAR_0 - 1);
        append_char_class (re_ctx_p, LIT_CHAR_9 + 1, LIT_CHAR_UPPERCASE_A - 1);
        append_char_class (re_ctx_p, LIT_CHAR_UPPERCASE_Z + 1, LIT_CHAR_UNDERSCORE - 1);
        append_char_class (re_ctx_p, LIT_CHAR_UNDERSCORE + 1, LIT_CHAR_LOWERCASE_A - 1);
        append_char_class (re_ctx_p, LIT_CHAR_LOWERCASE_Z + 1, LIT_UTF16_CODE_UNIT_MAX);
        ch = RE_CHAR_UNDEF;
      }
      else if (ch <= LIT_UTF16_CODE_UNIT_MAX
               && lit_char_is_octal_digit ((ecma_char_t) ch)
               && ch != LIT_CHAR_0)
      {
        parser_ctx_p->input_curr_p--;
        ch = re_parse_octal (parser_ctx_p);
      }
    } /* ch == LIT_CHAR_BACKSLASH */

    if (ch == RE_CHAR_UNDEF)
    {
      if (start != RE_CHAR_UNDEF)
      {
        if (is_range)
        {
          return ecma_raise_syntax_error ("invalid character class, invalid range");
        }
        else
        {
          append_char_class (re_ctx_p, start, start);
          start = RE_CHAR_UNDEF;
        }
      }
    }
    else
    {
      if (start != RE_CHAR_UNDEF)
      {
        if (is_range)
        {
          if (start > ch)
          {
            return ecma_raise_syntax_error ("invalid character class, wrong order");
          }
          else
          {
            append_char_class (re_ctx_p, start, ch);
            start = RE_CHAR_UNDEF;
            is_range = false;
          }
        }
        else
        {
          append_char_class (re_ctx_p, start, start);
          start = ch;
        }
      }
      else
      {
        start = ch;
      }
    }
  }
  while (token_type == RE_TOK_START_CHAR_CLASS || token_type == RE_TOK_START_INV_CHAR_CLASS);

  return re_parse_iterator (parser_ctx_p, out_token_p);
} /* re_parse_char_class */
Example #3
0
/**
 * Read the input pattern and parse the next token for the RegExp compiler
 *
 * @return completion value
 *         Returned value must be freed with ecma_free_completion_value
 */
ecma_completion_value_t
re_parse_next_token (re_parser_ctx_t *parser_ctx_p, /**< RegExp parser context */
                     re_token_t *out_token_p) /**< out: output token */
{
  ecma_completion_value_t ret_value = ecma_make_empty_completion_value ();

  if (parser_ctx_p->input_curr_p >= parser_ctx_p->input_end_p)
  {
    out_token_p->type = RE_TOK_EOF;
    return ret_value;
  }

  ecma_char_t ch = lit_utf8_read_next (&parser_ctx_p->input_curr_p);

  switch (ch)
  {
    case LIT_CHAR_VLINE:
    {
      out_token_p->type = RE_TOK_ALTERNATIVE;
      break;
    }
    case LIT_CHAR_CIRCUMFLEX:
    {
      out_token_p->type = RE_TOK_ASSERT_START;
      break;
    }
    case LIT_CHAR_DOLLAR_SIGN:
    {
      out_token_p->type = RE_TOK_ASSERT_END;
      break;
    }
    case LIT_CHAR_DOT:
    {
      out_token_p->type = RE_TOK_PERIOD;
      ret_value = re_parse_iterator (parser_ctx_p, out_token_p);
      break;
    }
    case LIT_CHAR_BACKSLASH:
    {
      if (parser_ctx_p->input_curr_p >= parser_ctx_p->input_end_p)
      {
        return ecma_raise_syntax_error ("invalid regular experssion");
      }

      out_token_p->type = RE_TOK_CHAR;
      ch = lit_utf8_read_next (&parser_ctx_p->input_curr_p);

      if (ch == LIT_CHAR_LOWERCASE_B)
      {
        out_token_p->type = RE_TOK_ASSERT_WORD_BOUNDARY;
      }
      else if (ch == LIT_CHAR_UPPERCASE_B)
      {
        out_token_p->type = RE_TOK_ASSERT_NOT_WORD_BOUNDARY;
      }
      else if (ch == LIT_CHAR_LOWERCASE_F)
      {
        out_token_p->value = LIT_CHAR_FF;
      }
      else if (ch == LIT_CHAR_LOWERCASE_N)
      {
        out_token_p->value = LIT_CHAR_LF;
      }
      else if (ch == LIT_CHAR_LOWERCASE_T)
      {
        out_token_p->value = LIT_CHAR_TAB;
      }
      else if (ch == LIT_CHAR_LOWERCASE_R)
      {
        out_token_p->value = LIT_CHAR_CR;
      }
      else if (ch == LIT_CHAR_LOWERCASE_V)
      {
        out_token_p->value = LIT_CHAR_VTAB;
      }
      else if (ch == LIT_CHAR_LOWERCASE_C)
      {
        if (parser_ctx_p->input_curr_p < parser_ctx_p->input_end_p)
        {
          ch = *parser_ctx_p->input_curr_p;

          if ((ch >= LIT_CHAR_ASCII_UPPERCASE_LETTERS_BEGIN && ch <= LIT_CHAR_ASCII_UPPERCASE_LETTERS_END)
              || (ch >= LIT_CHAR_ASCII_LOWERCASE_LETTERS_BEGIN && ch <= LIT_CHAR_ASCII_LOWERCASE_LETTERS_END))
          {
            out_token_p->value = (ch % 32);
            parser_ctx_p->input_curr_p++;
          }
          else
          {
            out_token_p->value = LIT_CHAR_BACKSLASH;
            parser_ctx_p->input_curr_p--;
          }
        }
        else
        {
          out_token_p->value = LIT_CHAR_BACKSLASH;
          parser_ctx_p->input_curr_p--;
        }
      }
      else if (ch == LIT_CHAR_LOWERCASE_X
               && re_hex_lookup (parser_ctx_p, 2))
      {
        lit_code_point_t code_point;

        if (!lit_read_code_point_from_hex (parser_ctx_p->input_curr_p, 2, &code_point))
        {
          return ecma_raise_syntax_error ("decode error");
        }

        parser_ctx_p->input_curr_p += 2;
        out_token_p->value = code_point;
      }
      else if (ch == LIT_CHAR_LOWERCASE_U
               && re_hex_lookup (parser_ctx_p, 4))
      {
        lit_code_point_t code_point;

        if (!lit_read_code_point_from_hex (parser_ctx_p->input_curr_p, 4, &code_point))
        {
          return ecma_raise_syntax_error ("decode error");
        }

        parser_ctx_p->input_curr_p += 4;
        out_token_p->value = code_point;
      }
      else if (ch == LIT_CHAR_LOWERCASE_D)
      {
        out_token_p->type = RE_TOK_DIGIT;
        break;
      }
      else if (ch == LIT_CHAR_UPPERCASE_D)
      {
        out_token_p->type = RE_TOK_NOT_DIGIT;
        break;
      }
      else if (ch == LIT_CHAR_LOWERCASE_S)
      {
        out_token_p->type = RE_TOK_WHITE;
        break;
      }
      else if (ch == LIT_CHAR_UPPERCASE_S)
      {
        out_token_p->type = RE_TOK_NOT_WHITE;
        break;
      }
      else if (ch == LIT_CHAR_LOWERCASE_W)
      {
        out_token_p->type = RE_TOK_WORD_CHAR;
        break;
      }
      else if (ch == LIT_CHAR_UPPERCASE_W)
      {
        out_token_p->type = RE_TOK_NOT_WORD_CHAR;
        break;
      }
      else if (lit_char_is_decimal_digit (ch))
      {
        if (ch == LIT_CHAR_0)
        {
          if (parser_ctx_p->input_curr_p < parser_ctx_p->input_end_p
              && lit_char_is_decimal_digit (*parser_ctx_p->input_curr_p))
          {
            return ecma_raise_syntax_error ("RegExp escape pattern error.");
          }

          out_token_p->value = LIT_UNICODE_CODE_POINT_NULL;
        }
        else
        {
          if (parser_ctx_p->num_of_groups == -1)
          {
            re_count_num_of_groups (parser_ctx_p);
          }

          if (parser_ctx_p->num_of_groups)
          {
            parser_ctx_p->input_curr_p--;
            uint32_t number = 0;
            int index = 0;

            do
            {
              if (index >= RE_MAX_RE_DECESC_DIGITS)
              {
                ret_value = ecma_raise_syntax_error ("RegExp escape pattern error: decimal escape too long.");
                return ret_value;
              }
              if (parser_ctx_p->input_curr_p >= parser_ctx_p->input_end_p)
              {
                break;
              }

              ecma_char_t digit = *parser_ctx_p->input_curr_p++;

              if (!lit_char_is_decimal_digit (digit))
              {
                parser_ctx_p->input_curr_p--;
                break;
              }
              number = number * 10 + lit_char_hex_to_int (digit);
              index++;
            }
            while (true);

            if ((int) number <= parser_ctx_p->num_of_groups)
            {
              out_token_p->type = RE_TOK_BACKREFERENCE;
            }
            else
            /* Invalid backreference, fallback to octal */
            {
              /* Rewind to start of number. */
              parser_ctx_p->input_curr_p -= index;

              /* Try to reparse as octal. */
              ecma_char_t digit = *parser_ctx_p->input_curr_p;

              if (!lit_char_is_octal_digit (digit))
              {
                /* Not octal, keep digit character value. */
                number = digit;
                parser_ctx_p->input_curr_p++;
              }
              else
              {
                number = re_parse_octal (parser_ctx_p);
              }
            }
            out_token_p->value = number;
          }
          else
          /* Invalid backreference, fallback to octal if possible */
          {
            if (!lit_char_is_octal_digit (ch))
            {
              /* Not octal, keep character value. */
              out_token_p->value = ch;
            }
            else
            {
              parser_ctx_p->input_curr_p--;
              out_token_p->value = re_parse_octal (parser_ctx_p);
            }
          }
        }
      }
      else
      {
        out_token_p->value = ch;
      }

      ret_value = re_parse_iterator (parser_ctx_p, out_token_p);
      break;
    }
    case LIT_CHAR_LEFT_PAREN:
    {
      if (parser_ctx_p->input_curr_p >= parser_ctx_p->input_end_p)
      {
        return ecma_raise_syntax_error ("Unterminated group");
      }

      if (*parser_ctx_p->input_curr_p == LIT_CHAR_QUESTION)
      {
        parser_ctx_p->input_curr_p++;
        if (parser_ctx_p->input_curr_p >= parser_ctx_p->input_end_p)
        {
          return ecma_raise_syntax_error ("Invalid group");
        }

        ch = *parser_ctx_p->input_curr_p++;

        if (ch == LIT_CHAR_EQUALS)
        {
          /* (?= */
          out_token_p->type = RE_TOK_ASSERT_START_POS_LOOKAHEAD;
        }
        else if (ch == LIT_CHAR_EXCLAMATION)
        {
          /* (?! */
          out_token_p->type = RE_TOK_ASSERT_START_NEG_LOOKAHEAD;
        }
        else if (ch == LIT_CHAR_COLON)
        {
          /* (?: */
          out_token_p->type = RE_TOK_START_NON_CAPTURE_GROUP;
        }
        else
        {
          return ecma_raise_syntax_error ("Invalid group");
        }
      }
      else
      {
        /* ( */
        out_token_p->type = RE_TOK_START_CAPTURE_GROUP;
      }
      break;
    }
    case LIT_CHAR_RIGHT_PAREN:
    {
      out_token_p->type = RE_TOK_END_GROUP;
      ret_value = re_parse_iterator (parser_ctx_p, out_token_p);
      break;
    }
    case LIT_CHAR_LEFT_SQUARE:
    {
      out_token_p->type = RE_TOK_START_CHAR_CLASS;

      if (parser_ctx_p->input_curr_p >= parser_ctx_p->input_end_p)
      {
        return ecma_raise_syntax_error ("invalid character class");
      }

      if (*parser_ctx_p->input_curr_p == LIT_CHAR_CIRCUMFLEX)
      {
        out_token_p->type = RE_TOK_START_INV_CHAR_CLASS;
        parser_ctx_p->input_curr_p++;
      }

      break;
    }
    case LIT_CHAR_QUESTION:
    case LIT_CHAR_ASTERISK:
    case LIT_CHAR_PLUS:
    case LIT_CHAR_LEFT_BRACE:
    {
      return ecma_raise_syntax_error ("Invalid RegExp token.");
    }
    case LIT_CHAR_NULL:
    {
      out_token_p->type = RE_TOK_EOF;
      break;
    }
    default:
    {
      out_token_p->type = RE_TOK_CHAR;
      out_token_p->value = ch;
      ret_value = re_parse_iterator (parser_ctx_p, out_token_p);
      break;
    }
  }

  return ret_value;
} /* re_parse_next_token */
Example #4
0
/**
 * Transforming escape sequences in the charset, outputting converted string to specified buffer
 *
 * Note:
 *      Size of string with transformed escape sequences is always
 *      less or equal to size of corresponding source string.
 *
 * @return size of converted string
 */
static lit_utf8_size_t
lexer_transform_escape_sequences (const jerry_api_char_t *source_str_p, /**< string to convert,
                                                                         *   located in source buffer */
                                  lit_utf8_size_t source_str_size, /**< size of the string and of the output buffer */
                                  jerry_api_char_t *output_str_buf_p) /**< output buffer for converted string */
{
  if (source_str_size == 0)
  {
    return 0;
  }
  else
  {
    JERRY_ASSERT (source_str_p != NULL);
  }

  lit_utf8_byte_t *output_str_buf_iter_p = output_str_buf_p;
  const size_t output_str_buf_size = source_str_size;
  bool is_correct_sequence = true;

  lit_utf8_iterator_t source_str_iter = lit_utf8_iterator_create (source_str_p,
                                                                  source_str_size);

  ecma_char_t prev_converted_char = LIT_CHAR_NULL;

  while (!lit_utf8_iterator_is_eos (&source_str_iter))
  {
    ecma_char_t converted_char;

    const ecma_char_t next_char = lit_utf8_iterator_read_next (&source_str_iter);

    if (next_char == LIT_CHAR_BACKSLASH)
    {
      if (lit_utf8_iterator_is_eos (&source_str_iter))
      {
        is_correct_sequence = false;
        break;
      }

      const ecma_char_t char_after_next = lit_utf8_iterator_read_next (&source_str_iter);

      if (lit_char_is_decimal_digit (char_after_next))
      {
        if (lit_char_is_octal_digit (char_after_next))
        {
          if (char_after_next == LIT_CHAR_0
              && (lit_utf8_iterator_is_eos (&source_str_iter)
                  || !lit_char_is_octal_digit (lit_utf8_iterator_peek_next (&source_str_iter))))
          {
            converted_char = LIT_CHAR_NULL;
          }
          else
          {
            /* Implementation-defined (ECMA-262 v5, B.1.2): octal escape sequences are not implemented */
            is_correct_sequence = false;
            break;
          }
        }
        else
        {
          converted_char = char_after_next;
        }
      }
      else if (char_after_next == LIT_CHAR_LOWERCASE_U
               || char_after_next == LIT_CHAR_LOWERCASE_X)
      {
        if (!lexer_convert_escape_sequence_digits_to_char (&source_str_iter,
                                                           char_after_next == LIT_CHAR_LOWERCASE_U,
                                                           &converted_char))
        {
          is_correct_sequence = false;
          break;
        }
      }
      else if (lit_char_is_line_terminator (char_after_next))
      {
        /* Skip \, followed by a LineTerminatorSequence (ECMA-262, v5, 7.3) */
        if (char_after_next == LIT_CHAR_CR
            && !lit_utf8_iterator_is_eos (&source_str_iter)
            && lit_utf8_iterator_peek_next (&source_str_iter) == LIT_CHAR_LF)
        {
          lit_utf8_iterator_incr (&source_str_iter);
        }

        continue;
      }
      else
      {
        lexer_convert_single_escape_character (char_after_next, &converted_char);
      }
    }
    else
    {
      converted_char = next_char;
    }

    if (lit_is_code_unit_high_surrogate (prev_converted_char)
        && lit_is_code_unit_low_surrogate (converted_char))
    {
      output_str_buf_iter_p -= LIT_UTF8_MAX_BYTES_IN_CODE_UNIT;

      lit_code_point_t code_point = lit_convert_surrogate_pair_to_code_point (prev_converted_char,
                                                                              converted_char);
      output_str_buf_iter_p += lit_code_point_to_utf8 (code_point, output_str_buf_iter_p);
    }
    else
    {
      output_str_buf_iter_p += lit_code_unit_to_utf8 (converted_char, output_str_buf_iter_p);
      JERRY_ASSERT (output_str_buf_iter_p <= output_str_buf_p + output_str_buf_size);
    }

    prev_converted_char = converted_char;
  }

  if (is_correct_sequence)
  {
    return (lit_utf8_size_t) (output_str_buf_iter_p - output_str_buf_p);
  }
  else
  {
    PARSE_ERROR (JSP_EARLY_ERROR_SYNTAX, "Illegal escape sequence", token_start_pos);
  }
} /* lexer_transform_escape_sequences */