Python code coverage for Lib/distutils/file_util.py

#	count	content
1	n/a	"""distutils.file_util
2	n/a
3	n/a	Utility functions for operating on single files.
4	n/a	"""
5	n/a
6	n/a	import os
7	n/a	from distutils.errors import DistutilsFileError
8	n/a	from distutils import log
9	n/a
10	n/a	# for generating verbose output in 'copy_file()'
11	n/a	_copy_action = { None: 'copying',
12	n/a	'hard': 'hard linking',
13	n/a	'sym': 'symbolically linking' }
14	n/a
15	n/a
16	n/a	def _copy_file_contents(src, dst, buffer_size=16*1024):
17	n/a	"""Copy the file 'src' to 'dst'; both must be filenames. Any error
18	n/a	opening either file, reading from 'src', or writing to 'dst', raises
19	n/a	DistutilsFileError. Data is read/written in chunks of 'buffer_size'
20	n/a	bytes (default 16k). No attempt is made to handle anything apart from
21	n/a	regular files.
22	n/a	"""
23	n/a	# Stolen from shutil module in the standard library, but with
24	n/a	# custom error-handling added.
25	n/a	fsrc = None
26	n/a	fdst = None
27	n/a	try:
28	n/a	try:
29	n/a	fsrc = open(src, 'rb')
30	n/a	except OSError as e:
31	n/a	raise DistutilsFileError("could not open '%s': %s" % (src, e.strerror))
32	n/a
33	n/a	if os.path.exists(dst):
34	n/a	try:
35	n/a	os.unlink(dst)
36	n/a	except OSError as e:
37	n/a	raise DistutilsFileError(
38	n/a	"could not delete '%s': %s" % (dst, e.strerror))
39	n/a
40	n/a	try:
41	n/a	fdst = open(dst, 'wb')
42	n/a	except OSError as e:
43	n/a	raise DistutilsFileError(
44	n/a	"could not create '%s': %s" % (dst, e.strerror))
45	n/a
46	n/a	while True:
47	n/a	try:
48	n/a	buf = fsrc.read(buffer_size)
49	n/a	except OSError as e:
50	n/a	raise DistutilsFileError(
51	n/a	"could not read from '%s': %s" % (src, e.strerror))
52	n/a
53	n/a	if not buf:
54	n/a	break
55	n/a
56	n/a	try:
57	n/a	fdst.write(buf)
58	n/a	except OSError as e:
59	n/a	raise DistutilsFileError(
60	n/a	"could not write to '%s': %s" % (dst, e.strerror))
61	n/a	finally:
62	n/a	if fdst:
63	n/a	fdst.close()
64	n/a	if fsrc:
65	n/a	fsrc.close()
66	n/a
67	n/a	def copy_file(src, dst, preserve_mode=1, preserve_times=1, update=0,
68	n/a	link=None, verbose=1, dry_run=0):
69	n/a	"""Copy a file 'src' to 'dst'. If 'dst' is a directory, then 'src' is
70	n/a	copied there with the same name; otherwise, it must be a filename. (If
71	n/a	the file exists, it will be ruthlessly clobbered.) If 'preserve_mode'
72	n/a	is true (the default), the file's mode (type and permission bits, or
73	n/a	whatever is analogous on the current platform) is copied. If
74	n/a	'preserve_times' is true (the default), the last-modified and
75	n/a	last-access times are copied as well. If 'update' is true, 'src' will
76	n/a	only be copied if 'dst' does not exist, or if 'dst' does exist but is
77	n/a	older than 'src'.
78	n/a
79	n/a	'link' allows you to make hard links (os.link) or symbolic links
80	n/a	(os.symlink) instead of copying: set it to "hard" or "sym"; if it is
81	n/a	None (the default), files are copied. Don't set 'link' on systems that
82	n/a	don't support it: 'copy_file()' doesn't check if hard or symbolic
83	n/a	linking is available. If hardlink fails, falls back to
84	n/a	_copy_file_contents().
85	n/a
86	n/a	Under Mac OS, uses the native file copy function in macostools; on
87	n/a	other systems, uses '_copy_file_contents()' to copy file contents.
88	n/a
89	n/a	Return a tuple (dest_name, copied): 'dest_name' is the actual name of
90	n/a	the output file, and 'copied' is true if the file was copied (or would
91	n/a	have been copied, if 'dry_run' true).
92	n/a	"""
93	n/a	# XXX if the destination file already exists, we clobber it if
94	n/a	# copying, but blow up if linking. Hmmm. And I don't know what
95	n/a	# macostools.copyfile() does. Should definitely be consistent, and
96	n/a	# should probably blow up if destination exists and we would be
97	n/a	# changing it (ie. it's not already a hard/soft link to src OR
98	n/a	# (not update) and (src newer than dst).
99	n/a
100	n/a	from distutils.dep_util import newer
101	n/a	from stat import ST_ATIME, ST_MTIME, ST_MODE, S_IMODE
102	n/a
103	n/a	if not os.path.isfile(src):
104	n/a	raise DistutilsFileError(
105	n/a	"can't copy '%s': doesn't exist or not a regular file" % src)
106	n/a
107	n/a	if os.path.isdir(dst):
108	n/a	dir = dst
109	n/a	dst = os.path.join(dst, os.path.basename(src))
110	n/a	else:
111	n/a	dir = os.path.dirname(dst)
112	n/a
113	n/a	if update and not newer(src, dst):
114	n/a	if verbose >= 1:
115	n/a	log.debug("not copying %s (output up-to-date)", src)
116	n/a	return (dst, 0)
117	n/a
118	n/a	try:
119	n/a	action = _copy_action[link]
120	n/a	except KeyError:
121	n/a	raise ValueError("invalid value '%s' for 'link' argument" % link)
122	n/a
123	n/a	if verbose >= 1:
124	n/a	if os.path.basename(dst) == os.path.basename(src):
125	n/a	log.info("%s %s -> %s", action, src, dir)
126	n/a	else:
127	n/a	log.info("%s %s -> %s", action, src, dst)
128	n/a
129	n/a	if dry_run:
130	n/a	return (dst, 1)
131	n/a
132	n/a	# If linking (hard or symbolic), use the appropriate system call
133	n/a	# (Unix only, of course, but that's the caller's responsibility)
134	n/a	elif link == 'hard':
135	n/a	if not (os.path.exists(dst) and os.path.samefile(src, dst)):
136	n/a	try:
137	n/a	os.link(src, dst)
138	n/a	return (dst, 1)
139	n/a	except OSError:
140	n/a	# If hard linking fails, fall back on copying file
141	n/a	# (some special filesystems don't support hard linking
142	n/a	# even under Unix, see issue #8876).
143	n/a	pass
144	n/a	elif link == 'sym':
145	n/a	if not (os.path.exists(dst) and os.path.samefile(src, dst)):
146	n/a	os.symlink(src, dst)
147	n/a	return (dst, 1)
148	n/a
149	n/a	# Otherwise (non-Mac, not linking), copy the file contents and
150	n/a	# (optionally) copy the times and mode.
151	n/a	_copy_file_contents(src, dst)
152	n/a	if preserve_mode or preserve_times:
153	n/a	st = os.stat(src)
154	n/a
155	n/a	# According to David Ascher <da@ski.org>, utime() should be done
156	n/a	# before chmod() (at least under NT).
157	n/a	if preserve_times:
158	n/a	os.utime(dst, (st[ST_ATIME], st[ST_MTIME]))
159	n/a	if preserve_mode:
160	n/a	os.chmod(dst, S_IMODE(st[ST_MODE]))
161	n/a
162	n/a	return (dst, 1)
163	n/a
164	n/a
165	n/a	# XXX I suspect this is Unix-specific -- need porting help!
166	n/a	def move_file (src, dst,
167	n/a	verbose=1,
168	n/a	dry_run=0):
169	n/a
170	n/a	"""Move a file 'src' to 'dst'. If 'dst' is a directory, the file will
171	n/a	be moved into it with the same name; otherwise, 'src' is just renamed
172	n/a	to 'dst'. Return the new full name of the file.
173	n/a
174	n/a	Handles cross-device moves on Unix using 'copy_file()'. What about
175	n/a	other systems???
176	n/a	"""
177	n/a	from os.path import exists, isfile, isdir, basename, dirname
178	n/a	import errno
179	n/a
180	n/a	if verbose >= 1:
181	n/a	log.info("moving %s -> %s", src, dst)
182	n/a
183	n/a	if dry_run:
184	n/a	return dst
185	n/a
186	n/a	if not isfile(src):
187	n/a	raise DistutilsFileError("can't move '%s': not a regular file" % src)
188	n/a
189	n/a	if isdir(dst):
190	n/a	dst = os.path.join(dst, basename(src))
191	n/a	elif exists(dst):
192	n/a	raise DistutilsFileError(
193	n/a	"can't move '%s': destination '%s' already exists" %
194	n/a	(src, dst))
195	n/a
196	n/a	if not isdir(dirname(dst)):
197	n/a	raise DistutilsFileError(
198	n/a	"can't move '%s': destination '%s' not a valid path" %
199	n/a	(src, dst))
200	n/a
201	n/a	copy_it = False
202	n/a	try:
203	n/a	os.rename(src, dst)
204	n/a	except OSError as e:
205	n/a	(num, msg) = e.args
206	n/a	if num == errno.EXDEV:
207	n/a	copy_it = True
208	n/a	else:
209	n/a	raise DistutilsFileError(
210	n/a	"couldn't move '%s' to '%s': %s" % (src, dst, msg))
211	n/a
212	n/a	if copy_it:
213	n/a	copy_file(src, dst, verbose=verbose)
214	n/a	try:
215	n/a	os.unlink(src)
216	n/a	except OSError as e:
217	n/a	(num, msg) = e.args
218	n/a	try:
219	n/a	os.unlink(dst)
220	n/a	except OSError:
221	n/a	pass
222	n/a	raise DistutilsFileError(
223	n/a	"couldn't move '%s' to '%s' by copy/delete: "
224	n/a	"delete '%s' failed: %s"
225	n/a	% (src, dst, src, msg))
226	n/a	return dst
227	n/a
228	n/a
229	n/a	def write_file (filename, contents):
230	n/a	"""Create a file with the specified name and write 'contents' (a
231	n/a	sequence of strings without line terminators) to it.
232	n/a	"""
233	n/a	f = open(filename, "w")
234	n/a	try:
235	n/a	for line in contents:
236	n/a	f.write(line + "\n")
237	n/a	finally:
238	n/a	f.close()