1 # Copyright (c) 2000 Autonomous Zone Industries
2 # Copyright (c) 2002-2007 Bryce "Zooko" Wilcox-O'Hearn
3 # This file is licensed under the
4 # GNU Lesser General Public License v2.1.
5 # See the file COPYING or visit http://www.gnu.org/ for details.
6 # Portions snarfed out of the Python standard library.
7 # The du part is due to Jim McCoy.
10 Futz with files like a pro.
13 import sys, exceptions, os, stat, tempfile, time
15 from twisted.python import log
17 def rename(src, dst, tries=4, basedelay=0.1):
18 """ Here is a superkludge to workaround the fact that occasionally on
19 Windows some other process (e.g. an anti-virus scanner, a local search
20 engine, etc.) is looking at your file when you want to delete or move it,
21 and hence you can't. The horrible workaround is to sit and spin, trying
22 to delete it, for a short time and then give up.
24 With the default values of tries and basedelay this can block for less
27 @param tries: number of tries -- each time after the first we wait twice
28 as long as the previous wait
29 @param basedelay: how long to wait before the second try
31 for i in range(tries-1):
33 return os.rename(src, dst)
34 except EnvironmentError, le:
35 # XXX Tighten this to check if this is a permission denied error (possibly due to another Windows process having the file open and execute the superkludge only in this case.
36 log.msg("XXX KLUDGE Attempting to move file %s => %s; got %s; sleeping %s seconds" % (src, dst, le, basedelay,))
39 return os.rename(src, dst) # The last try.
41 def remove(f, tries=4, basedelay=0.1):
42 """ Here is a superkludge to workaround the fact that occasionally on
43 Windows some other process (e.g. an anti-virus scanner, a local search
44 engine, etc.) is looking at your file when you want to delete or move it,
45 and hence you can't. The horrible workaround is to sit and spin, trying
46 to delete it, for a short time and then give up.
48 With the default values of tries and basedelay this can block for less
51 @param tries: number of tries -- each time after the first we wait twice
52 as long as the previous wait
53 @param basedelay: how long to wait before the second try
56 os.chmod(f, stat.S_IWRITE | stat.S_IEXEC | stat.S_IREAD)
59 for i in range(tries-1):
62 except EnvironmentError, le:
63 # XXX Tighten this to check if this is a permission denied error (possibly due to another Windows process having the file open and execute the superkludge only in this case.
64 if not os.path.exists(f):
66 log.msg("XXX KLUDGE Attempting to remove file %s; got %s; sleeping %s seconds" % (f, le, basedelay,))
69 return os.remove(f) # The last try.
71 class ReopenableNamedTemporaryFile:
73 This uses tempfile.mkstemp() to generate a secure temp file. It then closes
74 the file, leaving a zero-length file as a placeholder. You can get the
75 filename with ReopenableNamedTemporaryFile.name. When the
76 ReopenableNamedTemporaryFile instance is garbage collected or its shutdown()
77 method is called, it deletes the file.
79 def __init__(self, *args, **kwargs):
80 fd, self.name = tempfile.mkstemp(*args, **kwargs)
84 return "<%s instance at %x %s>" % (self.__class__.__name__, id(self), self.name)
87 return self.__repr__()
95 class NamedTemporaryDirectory:
97 This calls tempfile.mkdtemp(), stores the name of the dir in
98 self.name, and rmrf's the dir when it gets garbage collected or
101 def __init__(self, cleanup=True, *args, **kwargs):
102 """ If cleanup, then the directory will be rmrf'ed when the object is shutdown. """
103 self.cleanup = cleanup
104 self.name = tempfile.mkdtemp(*args, **kwargs)
107 return "<%s instance at %x %s>" % (self.__class__.__name__, id(self), self.name)
110 return self.__repr__()
117 traceback.print_exc()
120 if self.cleanup and hasattr(self, 'name'):
123 def make_dirs(dirname, mode=0777):
125 An idempotent version of os.makedirs(). If the dir already exists, do
126 nothing and return without raising an exception. If this call creates the
127 dir, return without raising an exception. If there is an error that
128 prevents creation or if the directory gets deleted after make_dirs() creates
129 it and before make_dirs() checks that it exists, raise an exception.
133 os.makedirs(dirname, mode)
137 if not os.path.isdir(dirname):
140 raise exceptions.IOError, "unknown error prevented creation of directory, or deleted the directory immediately after creation: %s" % dirname # careful not to construct an IOError with a 2-tuple, as that has a special meaning...
144 A threadsafe and idempotent version of shutil.rmtree(). If the dir is
145 already gone, do nothing and return without raising an exception. If this
146 call removes the dir, return without raising an exception. If there is an
147 error that prevents deletion or if the directory gets created again after
148 rm_dir() deletes it and before rm_dir() checks that it is gone, raise an
153 os.chmod(dirname, stat.S_IWRITE | stat.S_IEXEC | stat.S_IREAD)
154 for f in os.listdir(dirname):
155 fullname = os.path.join(dirname, f)
156 if os.path.isdir(fullname):
161 except Exception, le:
162 # Ignore "No such file or directory"
163 if (not isinstance(le, OSError)) or le.args[0] != 2:
166 # Okay, now we've recursively removed everything, ignoring any "No
167 # such file or directory" errors, and collecting any other errors.
169 if os.path.exists(dirname):
173 raise OSError, "Failed to remove dir for unknown reason."
177 def remove_if_possible(f):
183 def open_or_create(fname, binarymode=True):
185 return open(fname, binarymode and "r+b" or "r+")
186 except EnvironmentError:
187 return open(fname, binarymode and "w+b" or "w+")
192 for root, dirs, files in os.walk(basedir):
194 fn = os.path.join(root, f)
195 size += os.path.getsize(fn)
199 def move_into_place(source, dest):
200 """Atomically replace a file, or as near to it as the platform allows.
201 The dest file may or may not exist."""
202 if "win32" in sys.platform.lower():
203 remove_if_possible(dest)
204 os.rename(source, dest)