mirror of
https://github.com/pragma-/pbot.git
synced 2024-11-22 11:59:43 +01:00
84117d83c7
Also remove the explicit check for `ArrayRef`, which is obsolete since the 2014 addition of the `_is_simple_node` override in commit ba59edb04. (Upstream `_is_simple_node` returns `True` for an `ArrayRef`.)
85 lines
2.7 KiB
Python
Executable File
85 lines
2.7 KiB
Python
Executable File
#!/usr/bin/env python3
|
|
from __future__ import print_function
|
|
|
|
import sys
|
|
|
|
from pycparser import c_parser, c_generator, c_ast, plyparser
|
|
from pycparser.ply import yacc
|
|
|
|
with open("paren/stddef") as f:
|
|
STDDEF = f.read()
|
|
|
|
class CParser(c_parser.CParser):
|
|
def __init__(self, *a, **kw):
|
|
super(CParser, self).__init__(*a, **kw)
|
|
self.cparser = yacc.yacc(
|
|
module=self,
|
|
start='expression',
|
|
debug=kw.get('yacc_debug', False),
|
|
errorlog=yacc.NullLogger(),
|
|
optimize=kw.get('yacc_optimize', True),
|
|
tabmodule=kw.get('yacctab', 'yacctab'))
|
|
|
|
def parse(self, text, filename='', debuglevel=0):
|
|
self.clex.filename = filename
|
|
self.clex.reset_lineno()
|
|
self._scope_stack = [dict()]
|
|
self._last_yielded_token = None
|
|
for name in STDDEF.split('\n'):
|
|
if name:
|
|
self._add_typedef_name(name, None)
|
|
return self.cparser.parse(
|
|
input=text,
|
|
lexer=self.clex,
|
|
debug=debuglevel)
|
|
|
|
|
|
class CGenerator(c_generator.CGenerator):
|
|
def _is_simple_node(self, n):
|
|
return isinstance(n, (c_ast.Constant, c_ast.ID, c_ast.FuncCall))
|
|
|
|
def visit_UnaryOp(self, n):
|
|
# don't parenthesize an operand to sizeof if it's not a type
|
|
if n.op == 'sizeof':
|
|
if isinstance(n.expr, c_ast.Typename):
|
|
return 'sizeof (%s)' % self.visit(n.expr)
|
|
else:
|
|
return 'sizeof %s' % self._parenthesize_unless_simple(n.expr)
|
|
else:
|
|
operand = self.visit(n.expr)
|
|
if not self._is_simple_node(n.expr) or (n.op == '*' and isinstance(n.expr, c_ast.FuncCall)):
|
|
operand = '(%s)' % operand
|
|
if n.op in ('p++', 'p--'):
|
|
return operand + n.op[1:]
|
|
else:
|
|
return n.op + operand
|
|
|
|
def visit_TernaryOp(self, n):
|
|
return '({0}) ? ({1}) : ({2})'.format(
|
|
self.visit(n.cond),
|
|
self.visit(n.iftrue),
|
|
self.visit(n.iffalse))
|
|
|
|
def visit_Assignment(self, n):
|
|
return '%s %s %s' % (self.visit(n.lvalue), n.op, self._parenthesize_unless_simple(n.rvalue))
|
|
|
|
|
|
def parenthesize(source):
|
|
parser = CParser(yacc_optimize=False)
|
|
try:
|
|
ast = parser.parse(source, '<input>')
|
|
except plyparser.ParseError as e:
|
|
print("Error: " + e.args[0])
|
|
return
|
|
generator = CGenerator()
|
|
print(generator.visit(ast))
|
|
|
|
|
|
if __name__ == "__main__":
|
|
if len(sys.argv) > 1:
|
|
parenthesize(' '.join(sys.argv[1:]).rstrip(';'))
|
|
elif len(sys.argv) == 1:
|
|
print("Usage: paren <expression>")
|
|
else:
|
|
print('error')
|