aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/python/ipython/py3/IPython/utils/path.py
blob: ccb70dccd433022044aaa5b35fae450d601eb178 (plain) (blame)
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
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
# encoding: utf-8
"""
Utilities for path handling.
"""

# Copyright (c) IPython Development Team.
# Distributed under the terms of the Modified BSD License.

import os
import sys
import errno
import shutil
import random
import glob

from IPython.utils.process import system

#-----------------------------------------------------------------------------
# Code
#-----------------------------------------------------------------------------
fs_encoding = sys.getfilesystemencoding()

def _writable_dir(path):
    """Whether `path` is a directory, to which the user has write access."""
    return os.path.isdir(path) and os.access(path, os.W_OK)

if sys.platform == 'win32':
    def _get_long_path_name(path):
        """Get a long path name (expand ~) on Windows using ctypes.

        Examples
        --------

        >>> get_long_path_name('c:\\\\docume~1')
        'c:\\\\Documents and Settings'

        """
        try:
            import ctypes
        except ImportError as e: 
            raise ImportError('you need to have ctypes installed for this to work') from e
        _GetLongPathName = ctypes.windll.kernel32.GetLongPathNameW
        _GetLongPathName.argtypes = [ctypes.c_wchar_p, ctypes.c_wchar_p,
            ctypes.c_uint ]

        buf = ctypes.create_unicode_buffer(260)
        rv = _GetLongPathName(path, buf, 260)
        if rv == 0 or rv > 260:
            return path
        else:
            return buf.value
else:
    def _get_long_path_name(path):
        """Dummy no-op."""
        return path



def get_long_path_name(path):
    """Expand a path into its long form.

    On Windows this expands any ~ in the paths. On other platforms, it is
    a null operation.
    """
    return _get_long_path_name(path)


def compress_user(path):
    """Reverse of :func:`os.path.expanduser`
    """
    home = os.path.expanduser('~')
    if path.startswith(home):
        path =  "~" + path[len(home):]
    return path

def get_py_filename(name):
    """Return a valid python filename in the current directory.

    If the given name is not a file, it adds '.py' and searches again.
    Raises IOError with an informative message if the file isn't found.
    """

    name = os.path.expanduser(name)
    if os.path.isfile(name):
        return name
    if not name.endswith(".py"):
        py_name = name + ".py"
        if os.path.isfile(py_name):
            return py_name
    raise IOError("File `%r` not found." % name)


def filefind(filename: str, path_dirs=None) -> str:
    """Find a file by looking through a sequence of paths.

    This iterates through a sequence of paths looking for a file and returns
    the full, absolute path of the first occurrence of the file.  If no set of
    path dirs is given, the filename is tested as is, after running through
    :func:`expandvars` and :func:`expanduser`.  Thus a simple call::

        filefind('myfile.txt')

    will find the file in the current working dir, but::

        filefind('~/myfile.txt')

    Will find the file in the users home directory.  This function does not
    automatically try any paths, such as the cwd or the user's home directory.

    Parameters
    ----------
    filename : str
        The filename to look for.
    path_dirs : str, None or sequence of str
        The sequence of paths to look for the file in.  If None, the filename
        need to be absolute or be in the cwd.  If a string, the string is
        put into a sequence and the searched.  If a sequence, walk through
        each element and join with ``filename``, calling :func:`expandvars`
        and :func:`expanduser` before testing for existence.

    Returns
    -------
    path : str
        returns absolute path to file.

    Raises
    ------
    IOError
    """

    # If paths are quoted, abspath gets confused, strip them...
    filename = filename.strip('"').strip("'")
    # If the input is an absolute path, just check it exists
    if os.path.isabs(filename) and os.path.isfile(filename):
        return filename

    if path_dirs is None:
        path_dirs = ("",)
    elif isinstance(path_dirs, str):
        path_dirs = (path_dirs,)

    for path in path_dirs:
        if path == '.': path = os.getcwd()
        testname = expand_path(os.path.join(path, filename))
        if os.path.isfile(testname):
            return os.path.abspath(testname)

    raise IOError("File %r does not exist in any of the search paths: %r" %
                  (filename, path_dirs) )


class HomeDirError(Exception):
    pass


def get_home_dir(require_writable=False) -> str:
    """Return the 'home' directory, as a unicode string.

    Uses os.path.expanduser('~'), and checks for writability.

    See stdlib docs for how this is determined.
    For Python <3.8, $HOME is first priority on *ALL* platforms.
    For Python >=3.8 on Windows, %HOME% is no longer considered.

    Parameters
    ----------
    require_writable : bool [default: False]
        if True:
            guarantees the return value is a writable directory, otherwise
            raises HomeDirError
        if False:
            The path is resolved, but it is not guaranteed to exist or be writable.
    """

    homedir = os.path.expanduser('~')
    # Next line will make things work even when /home/ is a symlink to
    # /usr/home as it is on FreeBSD, for example
    homedir = os.path.realpath(homedir)

    if not _writable_dir(homedir) and os.name == 'nt':
        # expanduser failed, use the registry to get the 'My Documents' folder.
        try:
            import winreg as wreg
            with wreg.OpenKey(
                wreg.HKEY_CURRENT_USER,
                r"Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders"
            ) as key:
                homedir = wreg.QueryValueEx(key,'Personal')[0]
        except:
            pass

    if (not require_writable) or _writable_dir(homedir):
        assert isinstance(homedir, str), "Homedir should be unicode not bytes"
        return homedir
    else:
        raise HomeDirError('%s is not a writable dir, '
                'set $HOME environment variable to override' % homedir)

def get_xdg_dir():
    """Return the XDG_CONFIG_HOME, if it is defined and exists, else None.

    This is only for non-OS X posix (Linux,Unix,etc.) systems.
    """

    env = os.environ

    if os.name == "posix":
        # Linux, Unix, AIX, etc.
        # use ~/.config if empty OR not set
        xdg = env.get("XDG_CONFIG_HOME", None) or os.path.join(get_home_dir(), '.config')
        if xdg and _writable_dir(xdg):
            assert isinstance(xdg, str)
            return xdg

    return None


def get_xdg_cache_dir():
    """Return the XDG_CACHE_HOME, if it is defined and exists, else None.

    This is only for non-OS X posix (Linux,Unix,etc.) systems.
    """

    env = os.environ

    if os.name == "posix":
        # Linux, Unix, AIX, etc.
        # use ~/.cache if empty OR not set
        xdg = env.get("XDG_CACHE_HOME", None) or os.path.join(get_home_dir(), '.cache')
        if xdg and _writable_dir(xdg):
            assert isinstance(xdg, str)
            return xdg

    return None


def expand_path(s):
    """Expand $VARS and ~names in a string, like a shell

    :Examples:

       In [2]: os.environ['FOO']='test'

       In [3]: expand_path('variable FOO is $FOO')
       Out[3]: 'variable FOO is test'
    """
    # This is a pretty subtle hack. When expand user is given a UNC path
    # on Windows (\\server\share$\%username%), os.path.expandvars, removes
    # the $ to get (\\server\share\%username%). I think it considered $
    # alone an empty var. But, we need the $ to remains there (it indicates
    # a hidden share).
    if os.name=='nt':
        s = s.replace('$\\', 'IPYTHON_TEMP')
    s = os.path.expandvars(os.path.expanduser(s))
    if os.name=='nt':
        s = s.replace('IPYTHON_TEMP', '$\\')
    return s


def unescape_glob(string):
    """Unescape glob pattern in `string`."""
    def unescape(s):
        for pattern in '*[]!?':
            s = s.replace(r'\{0}'.format(pattern), pattern)
        return s
    return '\\'.join(map(unescape, string.split('\\\\')))


def shellglob(args):
    """
    Do glob expansion for each element in `args` and return a flattened list.

    Unmatched glob pattern will remain as-is in the returned list.

    """
    expanded = []
    # Do not unescape backslash in Windows as it is interpreted as
    # path separator:
    unescape = unescape_glob if sys.platform != 'win32' else lambda x: x
    for a in args:
        expanded.extend(glob.glob(a) or [unescape(a)])
    return expanded


def target_outdated(target,deps):
    """Determine whether a target is out of date.

    target_outdated(target,deps) -> 1/0

    deps: list of filenames which MUST exist.
    target: single filename which may or may not exist.

    If target doesn't exist or is older than any file listed in deps, return
    true, otherwise return false.
    """
    try:
        target_time = os.path.getmtime(target)
    except os.error:
        return 1
    for dep in deps:
        dep_time = os.path.getmtime(dep)
        if dep_time > target_time:
            #print "For target",target,"Dep failed:",dep # dbg
            #print "times (dep,tar):",dep_time,target_time # dbg
            return 1
    return 0


def target_update(target,deps,cmd):
    """Update a target with a given command given a list of dependencies.

    target_update(target,deps,cmd) -> runs cmd if target is outdated.

    This is just a wrapper around target_outdated() which calls the given
    command if target is outdated."""

    if target_outdated(target,deps):
        system(cmd)


ENOLINK = 1998

def link(src, dst):
    """Hard links ``src`` to ``dst``, returning 0 or errno.

    Note that the special errno ``ENOLINK`` will be returned if ``os.link`` isn't
    supported by the operating system.
    """

    if not hasattr(os, "link"):
        return ENOLINK
    link_errno = 0
    try:
        os.link(src, dst)
    except OSError as e:
        link_errno = e.errno
    return link_errno


def link_or_copy(src, dst):
    """Attempts to hardlink ``src`` to ``dst``, copying if the link fails.

    Attempts to maintain the semantics of ``shutil.copy``.

    Because ``os.link`` does not overwrite files, a unique temporary file
    will be used if the target already exists, then that file will be moved
    into place.
    """

    if os.path.isdir(dst):
        dst = os.path.join(dst, os.path.basename(src))

    link_errno = link(src, dst)
    if link_errno == errno.EEXIST:
        if os.stat(src).st_ino == os.stat(dst).st_ino:
            # dst is already a hard link to the correct file, so we don't need
            # to do anything else. If we try to link and rename the file
            # anyway, we get duplicate files - see http://bugs.python.org/issue21876
            return

        new_dst = dst + "-temp-%04X" %(random.randint(1, 16**4), )
        try:
            link_or_copy(src, new_dst)
        except:
            try:
                os.remove(new_dst)
            except OSError:
                pass
            raise
        os.rename(new_dst, dst)
    elif link_errno != 0:
        # Either link isn't supported, or the filesystem doesn't support
        # linking, or 'src' and 'dst' are on different filesystems.
        shutil.copy(src, dst)

def ensure_dir_exists(path, mode=0o755):
    """ensure that a directory exists

    If it doesn't exist, try to create it and protect against a race condition
    if another process is doing the same.

    The default permissions are 755, which differ from os.makedirs default of 777.
    """
    if not os.path.exists(path):
        try:
            os.makedirs(path, mode=mode)
        except OSError as e:
            if e.errno != errno.EEXIST:
                raise
    elif not os.path.isdir(path):
        raise IOError("%r exists but is not a directory" % path)