Python code coverage for Tools/scripts/pathfix.py

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