Staging
v0.5.1
v0.5.1
https://github.com/python/cpython
Tip revision: 74f4bd53e03ded8408bcc2de67cf0f5a4ac5b1a1 authored by Barry Warsaw on 23 February 2012, 15:59:38 UTC
Bump some more copyright years (as per PEP 101), since this is the first
Bump some more copyright years (as per PEP 101), since this is the first
Tip revision: 74f4bd5
ifdef.py
#! /usr/bin/env python
# Selectively preprocess #ifdef / #ifndef statements.
# Usage:
# ifdef [-Dname] ... [-Uname] ... [file] ...
#
# This scans the file(s), looking for #ifdef and #ifndef preprocessor
# commands that test for one of the names mentioned in the -D and -U
# options. On standard output it writes a copy of the input file(s)
# minus those code sections that are suppressed by the selected
# combination of defined/undefined symbols. The #if(n)def/#else/#else
# lines themselfs (if the #if(n)def tests for one of the mentioned
# names) are removed as well.
# Features: Arbitrary nesting of recognized and unrecognized
# preprocesor statements works correctly. Unrecognized #if* commands
# are left in place, so it will never remove too much, only too
# little. It does accept whitespace around the '#' character.
# Restrictions: There should be no comments or other symbols on the
# #if(n)def lines. The effect of #define/#undef commands in the input
# file or in included files is not taken into account. Tests using
# #if and the defined() pseudo function are not recognized. The #elif
# command is not recognized. Improperly nesting is not detected.
# Lines that look like preprocessor commands but which are actually
# part of comments or string literals will be mistaken for
# preprocessor commands.
import sys
import getopt
defs = []
undefs = []
def main():
opts, args = getopt.getopt(sys.argv[1:], 'D:U:')
for o, a in opts:
if o == '-D':
defs.append(a)
if o == '-U':
undefs.append(a)
if not args:
args = ['-']
for filename in args:
if filename == '-':
process(sys.stdin, sys.stdout)
else:
f = open(filename, 'r')
process(f, sys.stdout)
f.close()
def process(fpi, fpo):
keywords = ('if', 'ifdef', 'ifndef', 'else', 'endif')
ok = 1
stack = []
while 1:
line = fpi.readline()
if not line: break
while line[-2:] == '\\\n':
nextline = fpi.readline()
if not nextline: break
line = line + nextline
tmp = line.strip()
if tmp[:1] != '#':
if ok: fpo.write(line)
continue
tmp = tmp[1:].strip()
words = tmp.split()
keyword = words[0]
if keyword not in keywords:
if ok: fpo.write(line)
continue
if keyword in ('ifdef', 'ifndef') and len(words) == 2:
if keyword == 'ifdef':
ko = 1
else:
ko = 0
word = words[1]
if word in defs:
stack.append((ok, ko, word))
if not ko: ok = 0
elif word in undefs:
stack.append((ok, not ko, word))
if ko: ok = 0
else:
stack.append((ok, -1, word))
if ok: fpo.write(line)
elif keyword == 'if':
stack.append((ok, -1, ''))
if ok: fpo.write(line)
elif keyword == 'else' and stack:
s_ok, s_ko, s_word = stack[-1]
if s_ko < 0:
if ok: fpo.write(line)
else:
s_ko = not s_ko
ok = s_ok
if not s_ko: ok = 0
stack[-1] = s_ok, s_ko, s_word
elif keyword == 'endif' and stack:
s_ok, s_ko, s_word = stack[-1]
if s_ko < 0:
if ok: fpo.write(line)
del stack[-1]
ok = s_ok
else:
sys.stderr.write('Unknown keyword %s\n' % keyword)
if stack:
sys.stderr.write('stack: %s\n' % stack)
if __name__ == '__main__':
main()