Benjamin Peterson | 9abfc45 | 2009-09-25 20:56:52 +0000 | [diff] [blame] | 1 | #!/usr/bin/env python3 |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 2 | |
| 3 | # Change the #! line occurring in Python scripts. The new interpreter |
| 4 | # pathname must be given with a -i option. |
| 5 | # |
| 6 | # Command line arguments are files or directories to be processed. |
| 7 | # Directories are searched recursively for files whose name looks |
| 8 | # like a python module. |
| 9 | # Symbolic links are always ignored (except as explicit directory |
| 10 | # arguments). Of course, the original file is kept as a back-up |
| 11 | # (with a "~" attached to its name). |
| 12 | # |
| 13 | # Undoubtedly you can do this using find and sed or perl, but this is |
| 14 | # a nice example of Python code that recurses down a directory tree |
| 15 | # and uses regular expressions. Also note several subtleties like |
| 16 | # preserving the file's mode and avoiding to even write a temp file |
| 17 | # when no changes are needed for a file. |
| 18 | # |
| 19 | # NB: by changing only the function fixfile() you can turn this |
| 20 | # into a program for a different change to Python programs... |
| 21 | |
| 22 | import sys |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 23 | import re |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 24 | import os |
| 25 | from stat import * |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 26 | import getopt |
| 27 | |
| 28 | err = sys.stderr.write |
| 29 | dbg = err |
| 30 | rep = sys.stdout.write |
| 31 | |
| 32 | new_interpreter = None |
Senthil Kumaran | 7cd94b8 | 2010-10-19 04:39:35 +0000 | [diff] [blame] | 33 | preserve_timestamps = False |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 34 | |
| 35 | def main(): |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 36 | global new_interpreter |
Senthil Kumaran | 7cd94b8 | 2010-10-19 04:39:35 +0000 | [diff] [blame] | 37 | global preserve_timestamps |
| 38 | usage = ('usage: %s -i /interpreter -p file-or-directory ...\n' % |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 39 | sys.argv[0]) |
| 40 | try: |
Senthil Kumaran | 7cd94b8 | 2010-10-19 04:39:35 +0000 | [diff] [blame] | 41 | opts, args = getopt.getopt(sys.argv[1:], 'i:p') |
Guido van Rossum | b940e11 | 2007-01-10 16:19:56 +0000 | [diff] [blame] | 42 | except getopt.error as msg: |
Senthil Kumaran | 7cd94b8 | 2010-10-19 04:39:35 +0000 | [diff] [blame] | 43 | err(str(msg) + '\n') |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 44 | err(usage) |
| 45 | sys.exit(2) |
| 46 | for o, a in opts: |
| 47 | if o == '-i': |
Benjamin Peterson | 9abfc45 | 2009-09-25 20:56:52 +0000 | [diff] [blame] | 48 | new_interpreter = a.encode() |
Senthil Kumaran | 7cd94b8 | 2010-10-19 04:39:35 +0000 | [diff] [blame] | 49 | if o == '-p': |
| 50 | preserve_timestamps = True |
Benjamin Peterson | 9abfc45 | 2009-09-25 20:56:52 +0000 | [diff] [blame] | 51 | if not new_interpreter or not new_interpreter.startswith(b'/') or \ |
| 52 | not args: |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 53 | err('-i option or file-or-directory missing\n') |
| 54 | err(usage) |
| 55 | sys.exit(2) |
| 56 | bad = 0 |
| 57 | for arg in args: |
| 58 | if os.path.isdir(arg): |
| 59 | if recursedown(arg): bad = 1 |
| 60 | elif os.path.islink(arg): |
| 61 | err(arg + ': will not process symbolic links\n') |
| 62 | bad = 1 |
| 63 | else: |
| 64 | if fix(arg): bad = 1 |
| 65 | sys.exit(bad) |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 66 | |
Thomas Wouters | 49fd7fa | 2006-04-21 10:40:58 +0000 | [diff] [blame] | 67 | ispythonprog = re.compile('^[a-zA-Z0-9_]+\.py$') |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 68 | def ispython(name): |
Benjamin Peterson | 9abfc45 | 2009-09-25 20:56:52 +0000 | [diff] [blame] | 69 | return bool(ispythonprog.match(name)) |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 70 | |
| 71 | def recursedown(dirname): |
Walter Dörwald | 70a6b49 | 2004-02-12 17:35:32 +0000 | [diff] [blame] | 72 | dbg('recursedown(%r)\n' % (dirname,)) |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 73 | bad = 0 |
| 74 | try: |
| 75 | names = os.listdir(dirname) |
Andrew Svetlov | 8b33dd8 | 2012-12-24 19:58:48 +0200 | [diff] [blame^] | 76 | except OSError as msg: |
Walter Dörwald | 70a6b49 | 2004-02-12 17:35:32 +0000 | [diff] [blame] | 77 | err('%s: cannot list directory: %r\n' % (dirname, msg)) |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 78 | return 1 |
| 79 | names.sort() |
| 80 | subdirs = [] |
| 81 | for name in names: |
| 82 | if name in (os.curdir, os.pardir): continue |
| 83 | fullname = os.path.join(dirname, name) |
| 84 | if os.path.islink(fullname): pass |
| 85 | elif os.path.isdir(fullname): |
| 86 | subdirs.append(fullname) |
| 87 | elif ispython(name): |
| 88 | if fix(fullname): bad = 1 |
| 89 | for fullname in subdirs: |
| 90 | if recursedown(fullname): bad = 1 |
| 91 | return bad |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 92 | |
| 93 | def fix(filename): |
Walter Dörwald | 70a6b49 | 2004-02-12 17:35:32 +0000 | [diff] [blame] | 94 | ## dbg('fix(%r)\n' % (filename,)) |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 95 | try: |
Benjamin Peterson | 9abfc45 | 2009-09-25 20:56:52 +0000 | [diff] [blame] | 96 | f = open(filename, 'rb') |
Guido van Rossum | b940e11 | 2007-01-10 16:19:56 +0000 | [diff] [blame] | 97 | except IOError as msg: |
Walter Dörwald | 70a6b49 | 2004-02-12 17:35:32 +0000 | [diff] [blame] | 98 | err('%s: cannot open: %r\n' % (filename, msg)) |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 99 | return 1 |
| 100 | line = f.readline() |
| 101 | fixed = fixline(line) |
| 102 | if line == fixed: |
| 103 | rep(filename+': no change\n') |
| 104 | f.close() |
| 105 | return |
| 106 | head, tail = os.path.split(filename) |
| 107 | tempname = os.path.join(head, '@' + tail) |
| 108 | try: |
Benjamin Peterson | 9abfc45 | 2009-09-25 20:56:52 +0000 | [diff] [blame] | 109 | g = open(tempname, 'wb') |
Guido van Rossum | b940e11 | 2007-01-10 16:19:56 +0000 | [diff] [blame] | 110 | except IOError as msg: |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 111 | f.close() |
Walter Dörwald | 70a6b49 | 2004-02-12 17:35:32 +0000 | [diff] [blame] | 112 | err('%s: cannot create: %r\n' % (tempname, msg)) |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 113 | return 1 |
| 114 | rep(filename + ': updating\n') |
| 115 | g.write(fixed) |
| 116 | BUFSIZE = 8*1024 |
| 117 | while 1: |
| 118 | buf = f.read(BUFSIZE) |
| 119 | if not buf: break |
| 120 | g.write(buf) |
| 121 | g.close() |
| 122 | f.close() |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 123 | |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 124 | # Finishing touch -- move files |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 125 | |
Senthil Kumaran | 7cd94b8 | 2010-10-19 04:39:35 +0000 | [diff] [blame] | 126 | mtime = None |
| 127 | atime = None |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 128 | # First copy the file's mode to the temp file |
| 129 | try: |
| 130 | statbuf = os.stat(filename) |
Senthil Kumaran | 7cd94b8 | 2010-10-19 04:39:35 +0000 | [diff] [blame] | 131 | mtime = statbuf.st_mtime |
| 132 | atime = statbuf.st_atime |
Guido van Rossum | cd16bf6 | 2007-06-13 18:07:49 +0000 | [diff] [blame] | 133 | os.chmod(tempname, statbuf[ST_MODE] & 0o7777) |
Andrew Svetlov | 8b33dd8 | 2012-12-24 19:58:48 +0200 | [diff] [blame^] | 134 | except OSError as msg: |
Walter Dörwald | 70a6b49 | 2004-02-12 17:35:32 +0000 | [diff] [blame] | 135 | err('%s: warning: chmod failed (%r)\n' % (tempname, msg)) |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 136 | # Then make a backup of the original file as filename~ |
| 137 | try: |
| 138 | os.rename(filename, filename + '~') |
Andrew Svetlov | 8b33dd8 | 2012-12-24 19:58:48 +0200 | [diff] [blame^] | 139 | except OSError as msg: |
Walter Dörwald | 70a6b49 | 2004-02-12 17:35:32 +0000 | [diff] [blame] | 140 | err('%s: warning: backup failed (%r)\n' % (filename, msg)) |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 141 | # Now move the temp file to the original file |
| 142 | try: |
| 143 | os.rename(tempname, filename) |
Andrew Svetlov | 8b33dd8 | 2012-12-24 19:58:48 +0200 | [diff] [blame^] | 144 | except OSError as msg: |
Walter Dörwald | 70a6b49 | 2004-02-12 17:35:32 +0000 | [diff] [blame] | 145 | err('%s: rename failed (%r)\n' % (filename, msg)) |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 146 | return 1 |
Senthil Kumaran | 7cd94b8 | 2010-10-19 04:39:35 +0000 | [diff] [blame] | 147 | if preserve_timestamps: |
| 148 | if atime and mtime: |
| 149 | try: |
| 150 | os.utime(filename, (atime, mtime)) |
Andrew Svetlov | 8b33dd8 | 2012-12-24 19:58:48 +0200 | [diff] [blame^] | 151 | except OSError as msg: |
Senthil Kumaran | 7cd94b8 | 2010-10-19 04:39:35 +0000 | [diff] [blame] | 152 | err('%s: reset of timestamp failed (%r)\n' % (filename, msg)) |
| 153 | return 1 |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 154 | # Return succes |
| 155 | return 0 |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 156 | |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 157 | def fixline(line): |
Benjamin Peterson | 9abfc45 | 2009-09-25 20:56:52 +0000 | [diff] [blame] | 158 | if not line.startswith(b'#!'): |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 159 | return line |
Benjamin Peterson | 9abfc45 | 2009-09-25 20:56:52 +0000 | [diff] [blame] | 160 | if b"python" not in line: |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 161 | return line |
Benjamin Peterson | 9abfc45 | 2009-09-25 20:56:52 +0000 | [diff] [blame] | 162 | return b'#! ' + new_interpreter + b'\n' |
Guido van Rossum | 9af22a0 | 1994-08-19 15:02:57 +0000 | [diff] [blame] | 163 | |
Andrew M. Kuchling | e236b38 | 2004-08-09 17:27:55 +0000 | [diff] [blame] | 164 | if __name__ == '__main__': |
| 165 | main() |