| Guido van Rossum | 7faf67c | 1994-05-09 14:52:41 +0000 | [diff] [blame] | 1 | #! /usr/local/bin/python |
| 2 | |
| 3 | # Selectively preprocess #ifdef / #ifndef statements. |
| 4 | # Usage: |
| 5 | # ifdef [-Dname] ... [-Uname] ... [file] ... |
| 6 | # |
| 7 | # This scans the file(s), looking for #ifdef and #ifndef preprocessor |
| 8 | # commands that test for one of the names mentioned in the -D and -U |
| 9 | # options. On standard output it writes a copy of the input file(s) |
| 10 | # minus those code sections that are suppressed by the selected |
| 11 | # combination of defined/undefined symbols. The #if(n)def/#else/#else |
| 12 | # lines themselfs (if the #if(n)def tests for one of the mentioned |
| 13 | # names) are removed as well. |
| 14 | |
| 15 | # Features: Arbitrary nesting of recognized and unrecognized |
| 16 | # preprocesor statements works correctly. Unrecognized #if* commands |
| 17 | # are left in place, so it will never remove too much, only too |
| 18 | # little. It does accept whitespace around the '#' character. |
| 19 | |
| 20 | # Restrictions: There should be no comments or other symbols on the |
| 21 | # #if(n)def lines. The effect of #define/#undef commands in the input |
| 22 | # file or in included files is not taken into account. Tests using |
| 23 | # #if and the defined() pseudo function are not recognized. The #elif |
| 24 | # command is not recognized. Improperly nesting is not detected. |
| 25 | # Lines that look like preprocessor commands but which are actually |
| 26 | # part of comments or string literals will be mistaken for |
| 27 | # preprocessor commands. |
| 28 | |
| 29 | import sys |
| 30 | import regex |
| 31 | import getopt |
| 32 | import string |
| 33 | |
| 34 | defs = [] |
| 35 | undefs = [] |
| 36 | |
| 37 | def main(): |
| 38 | opts, args = getopt.getopt(sys.argv[1:], 'D:U:') |
| 39 | for o, a in opts: |
| 40 | if o == '-D': |
| 41 | defs.append(a) |
| 42 | if o == '-U': |
| 43 | undefs.append(a) |
| 44 | if not args: |
| 45 | args = ['-'] |
| 46 | for file in args: |
| 47 | if file == '-': |
| 48 | process(sys.stdin, sys.stdout) |
| 49 | else: |
| 50 | f = open(file, 'r') |
| 51 | process(f, sys.stdout) |
| 52 | f.close() |
| 53 | |
| 54 | def process(fpi, fpo): |
| 55 | keywords = ('if', 'ifdef', 'ifndef', 'else', 'endif') |
| 56 | ok = 1 |
| 57 | stack = [] |
| 58 | while 1: |
| 59 | line = fpi.readline() |
| 60 | if not line: break |
| 61 | while line[-2:] == '\\\n': |
| 62 | nextline = fpi.readline() |
| 63 | if not nextline: break |
| 64 | line = line + nextline |
| 65 | tmp = string.strip(line) |
| 66 | if tmp[:1] != '#': |
| 67 | if ok: fpo.write(line) |
| 68 | continue |
| 69 | tmp = string.strip(tmp[1:]) |
| 70 | words = string.split(tmp) |
| 71 | keyword = words[0] |
| 72 | if keyword not in keywords: |
| 73 | if ok: fpo.write(line) |
| 74 | continue |
| 75 | if keyword in ('ifdef', 'ifndef') and len(words) == 2: |
| 76 | if keyword == 'ifdef': |
| 77 | ko = 1 |
| 78 | else: |
| 79 | ko = 0 |
| 80 | word = words[1] |
| 81 | if word in defs: |
| 82 | stack.append(ok, ko, word) |
| 83 | if not ko: ok = 0 |
| 84 | elif word in undefs: |
| 85 | stack.append(ok, not ko, word) |
| 86 | if ko: ok = 0 |
| 87 | else: |
| 88 | stack.append(ok, -1, word) |
| 89 | if ok: fpo.write(line) |
| 90 | elif keyword == 'if': |
| 91 | stack.append(ok, -1, '') |
| 92 | if ok: fpo.write(line) |
| 93 | elif keyword == 'else' and stack: |
| 94 | s_ok, s_ko, s_word = stack[-1] |
| 95 | if s_ko < 0: |
| 96 | if ok: fpo.write(line) |
| 97 | else: |
| 98 | s_ko = not s_ko |
| 99 | ok = s_ok |
| 100 | if not s_ko: ok = 0 |
| 101 | stack[-1] = s_ok, s_ko, s_word |
| 102 | elif keyword == 'endif' and stack: |
| 103 | s_ok, s_ko, s_word = stack[-1] |
| 104 | if s_ko < 0: |
| 105 | if ok: fpo.write(line) |
| 106 | del stack[-1] |
| 107 | ok = s_ok |
| 108 | else: |
| 109 | sys.stderr.write('Unknown keyword %s\n' % keyword) |
| 110 | if stack: |
| 111 | sys.stderr.write('stack: %s\n' % stack) |
| 112 | |
| 113 | main() |