Method resolve_expr

qiling/debugger/qdb/helper.py:90–128

Resolve an arithmetic expression that might include register names. Registers names will be substituted with their current value before proceeding to evaluate the expression. Args: expr: an expression to evaluate Returns: final evaluation re

(self, expr: str)

        return re.sub(r'\$(\w+)', __sub_reg, expr)

    def resolve_expr(self, expr: str) -> int:
        """Resolve an arithmetic expression that might include register names.

        Registers names will be substituted with their current value before
        proceeding to evaluate the expression.

        Args:
            expr: an expression to evaluate

        Returns:
            final evaluation result

        Raises:
            KeyError: if `expr` contains an unrecognized register name
            ValueError: if `expr` contains disallowed tokens
            SyntaxError: if `expr` contains a broken arithmetic syntax
        """

        try:
            # look for registers names  and replace them with their actual values
            expr = self.sub_reg_values(expr)

        # expr contains an unrecognized register name
        except KeyError as ex:
            raise KeyError(f'unrecognized register name: {ex.args[0]}') from ex

        try:
            # expr should contain only values and aithmetic tokens by now; attempt to evaluate it
            res = safe_arith(expr)

        # expr contains a disallowed token
        except ValueError as ex:
            raise ValueError('only integers, hexadecimals, octals, arithmetic and bitwise operators are allowed') from ex

        # arithmetic syntax is broken
        except SyntaxError as ex:
            raise SyntaxError('error evaluating arithmetic expression') from ex

        return res

    def handle_set(self, line: str) -> Tuple[str, int]:
        """