1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
|
# This file was taken from the python standard library and has been
# slightly modified to do a "yield" after every 16KB of copying
"""Utility functions for copying files and directory trees.
XXX The functions here don't copy the resource fork or other metadata on Mac.
"""
import os
import sys
import stat
from os.path import abspath
__all__ = ["copyfileobj","copyfile","copystat","copy2",
"copytree","move","rmtree","Error", "SpecialFileError"]
APPENDIX = '_'
class Error(EnvironmentError):
pass
class SpecialFileError(EnvironmentError):
"""Raised when trying to do a kind of operation (e.g. copying) which is
not supported on a special file (e.g. a named pipe)"""
try:
WindowsError
except NameError:
WindowsError = None
def copyfileobj(fsrc, fdst, length=16*1024):
"""copy data from file-like object fsrc to file-like object fdst"""
while 1:
buf = fsrc.read(length)
if not buf:
break
fdst.write(buf)
yield
def _samefile(src, dst):
# Macintosh, Unix.
if hasattr(os.path,'samefile'):
try:
return os.path.samefile(src, dst)
except OSError:
return False
# All other platforms: check for same pathname.
return (os.path.normcase(abspath(src)) ==
os.path.normcase(abspath(dst)))
def copyfile(src, dst):
"""Copy data from src to dst"""
if _samefile(src, dst):
raise Error("`%s` and `%s` are the same file" % (src, dst))
fsrc = None
fdst = None
for fn in [src, dst]:
try:
st = os.stat(fn)
except OSError:
# File most likely does not exist
pass
else:
# XXX What about other special files? (sockets, devices...)
if stat.S_ISFIFO(st.st_mode):
raise SpecialFileError("`%s` is a named pipe" % fn)
try:
fsrc = open(src, 'rb')
fdst = open(dst, 'wb')
for _ in copyfileobj(fsrc, fdst):
yield
finally:
if fdst:
fdst.close()
if fsrc:
fsrc.close()
def copystat(src, dst):
"""Copy all stat info (mode bits, atime, mtime, flags) from src to dst"""
st = os.stat(src)
mode = stat.S_IMODE(st.st_mode)
if hasattr(os, 'utime'):
try: os.utime(dst, (st.st_atime, st.st_mtime))
except: pass
if hasattr(os, 'chmod'):
try: os.chmod(dst, mode)
except: pass
if hasattr(os, 'chflags') and hasattr(st, 'st_flags'):
try: os.chflags(dst, st.st_flags)
except: pass
def copy2(src, dst, overwrite=False, symlinks=False):
"""Copy data and all stat info ("cp -p src dst").
The destination may be a directory.
"""
if os.path.isdir(dst):
dst = os.path.join(dst, os.path.basename(src))
if not overwrite:
dst = get_safe_path(dst)
if symlinks and os.path.islink(src):
linkto = os.readlink(src)
os.symlink(linkto, dst)
else:
for _ in copyfile(src, dst):
yield
copystat(src, dst)
def get_safe_path(dst):
if not os.path.exists(dst):
return dst
if not dst.endswith(APPENDIX):
dst += APPENDIX
if not os.path.exists(dst):
return dst
n = 0
test_dst = dst + str(n)
while os.path.exists(test_dst):
n += 1
test_dst = dst + str(n)
return test_dst
def copytree(src, dst, symlinks=False, ignore=None, overwrite=False):
"""Recursively copy a directory tree using copy2().
The destination directory must not already exist.
If exception(s) occur, an Error is raised with a list of reasons.
If the optional symlinks flag is true, symbolic links in the
source tree result in symbolic links in the destination tree; if
it is false, the contents of the files pointed to by symbolic
links are copied.
The optional ignore argument is a callable. If given, it
is called with the `src` parameter, which is the directory
being visited by copytree(), and `names` which is the list of
`src` contents, as returned by os.listdir():
callable(src, names) -> ignored_names
Since copytree() is called recursively, the callable will be
called once for each directory that is copied. It returns a
list of names relative to the `src` directory that should
not be copied.
XXX Consider this example code rather than the ultimate tool.
"""
names = os.listdir(src)
if ignore is not None:
ignored_names = ignore(src, names)
else:
ignored_names = set()
errors = []
try:
os.makedirs(dst)
except Exception as err:
if not overwrite:
dst = get_safe_path(dst)
os.makedirs(dst)
for name in names:
if name in ignored_names:
continue
srcname = os.path.join(src, name)
dstname = os.path.join(dst, name)
try:
if symlinks and os.path.islink(srcname):
linkto = os.readlink(srcname)
if os.path.lexists(dstname):
if not os.path.islink(dstname) \
or os.readlink(dstname) != linkto:
os.unlink(dstname)
os.symlink(linkto, dstname)
elif os.path.isdir(srcname):
for _ in copytree(srcname, dstname, symlinks,
ignore, overwrite):
yield
else:
# Will raise a SpecialFileError for unsupported file types
for _ in copy2(srcname, dstname,
overwrite=overwrite, symlinks=symlinks):
yield
# catch the Error from the recursive copytree so that we can
# continue with other files
except Error as err:
errors.extend(err.args[0])
except EnvironmentError as why:
errors.append((srcname, dstname, str(why)))
try:
copystat(src, dst)
except OSError as why:
if WindowsError is not None and isinstance(why, WindowsError):
# Copying file access times may fail on Windows
pass
else:
errors.extend((src, dst, str(why)))
if errors:
raise Error(errors)
def rmtree(path, ignore_errors=False, onerror=None):
"""Recursively delete a directory tree.
If ignore_errors is set, errors are ignored; otherwise, if onerror
is set, it is called to handle the error with arguments (func,
path, exc_info) where func is os.listdir, os.remove, or os.rmdir;
path is the argument to that function that caused it to fail; and
exc_info is a tuple returned by sys.exc_info(). If ignore_errors
is false and onerror is None, an exception is raised.
"""
if ignore_errors:
def onerror(*args):
pass
elif onerror is None:
def onerror(*args):
raise
try:
if os.path.islink(path):
# symlinks to directories are forbidden, see bug #1669
raise OSError("Cannot call rmtree on a symbolic link")
except OSError:
onerror(os.path.islink, path, sys.exc_info())
# can't continue even if onerror hook returns
return
names = []
try:
names = os.listdir(path)
except os.error as err:
onerror(os.listdir, path, sys.exc_info())
for name in names:
fullname = os.path.join(path, name)
try:
mode = os.lstat(fullname).st_mode
except os.error:
mode = 0
if stat.S_ISDIR(mode):
rmtree(fullname, ignore_errors, onerror)
else:
try:
os.remove(fullname)
except os.error as err:
onerror(os.remove, fullname, sys.exc_info())
try:
os.rmdir(path)
except os.error:
onerror(os.rmdir, path, sys.exc_info())
def _basename(path):
# A basename() variant which first strips the trailing slash, if present.
# Thus we always get the last component of the path, even for directories.
return os.path.basename(path.rstrip(os.path.sep))
def move(src, dst, overwrite=False):
"""Recursively move a file or directory to another location. This is
similar to the Unix "mv" command.
If the destination is a directory or a symlink to a directory, the source
is moved inside the directory. The destination path must not already
exist.
If the destination already exists but is not a directory, it may be
overwritten depending on os.rename() semantics.
If the destination is on our current filesystem, then rename() is used.
Otherwise, src is copied to the destination and then removed.
A lot more could be done here... A look at a mv.c shows a lot of
the issues this implementation glosses over.
"""
real_dst = dst
if not overwrite:
real_dst = get_safe_path(os.path.join(dst, _basename(src)))
try:
os.rename(src, real_dst)
except OSError:
if os.path.isdir(src):
if _destinsrc(src, dst):
raise Error("Cannot move a directory '%s' into itself '%s'." % (src, dst))
for _ in copytree(src, real_dst, symlinks=True, overwrite=overwrite):
yield
rmtree(src)
else:
for _ in copy2(src, real_dst, symlinks=True, overwrite=overwrite):
yield
os.unlink(src)
def _destinsrc(src, dst):
src = abspath(src)
dst = abspath(dst)
if not src.endswith(os.path.sep):
src += os.path.sep
if not dst.endswith(os.path.sep):
dst += os.path.sep
return dst.startswith(src)
# vi: expandtab sts=4 ts=4 sw=4
|