3
# Selectively preprocess #ifdef / #ifndef statements.
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# ifdef [-Dname] ... [-Uname] ... [file] ...
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# This scans the file(s), looking for #ifdef and #ifndef preprocessor
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# commands that test for one of the names mentioned in the -D and -U
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# options. On standard output it writes a copy of the input file(s)
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# minus those code sections that are suppressed by the selected
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# combination of defined/undefined symbols. The #if(n)def/#else/#else
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# lines themselfs (if the #if(n)def tests for one of the mentioned
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# names) are removed as well.
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# Features: Arbitrary nesting of recognized and unrecognized
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# preprocesor statements works correctly. Unrecognized #if* commands
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# are left in place, so it will never remove too much, only too
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# little. It does accept whitespace around the '#' character.
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# Restrictions: There should be no comments or other symbols on the
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# #if(n)def lines. The effect of #define/#undef commands in the input
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# file or in included files is not taken into account. Tests using
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# #if and the defined() pseudo function are not recognized. The #elif
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# command is not recognized. Improperly nesting is not detected.
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# Lines that look like preprocessor commands but which are actually
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# part of comments or string literals will be mistaken for
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# preprocessor commands.
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opts, args = getopt.getopt(sys.argv[1:], 'D:U:')
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process(sys.stdin, sys.stdout)
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f = open(filename, 'r')
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process(f, sys.stdout)
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def process(fpi, fpo):
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keywords = ('if', 'ifdef', 'ifndef', 'else', 'endif')
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while line[-2:] == '\\\n':
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nextline = fpi.readline()
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if not nextline: break
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line = line + nextline
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if ok: fpo.write(line)
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if keyword not in keywords:
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if ok: fpo.write(line)
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if keyword in ('ifdef', 'ifndef') and len(words) == 2:
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if keyword == 'ifdef':
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stack.append((ok, ko, word))
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stack.append((ok, not ko, word))
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stack.append((ok, -1, word))
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if ok: fpo.write(line)
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stack.append((ok, -1, ''))
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if ok: fpo.write(line)
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elif keyword == 'else' and stack:
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s_ok, s_ko, s_word = stack[-1]
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if ok: fpo.write(line)
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stack[-1] = s_ok, s_ko, s_word
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elif keyword == 'endif' and stack:
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s_ok, s_ko, s_word = stack[-1]
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if ok: fpo.write(line)
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sys.stderr.write('Unknown keyword %s\n' % keyword)
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sys.stderr.write('stack: %s\n' % stack)
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if __name__ == '__main__':