blob: b5147c233dc545952790a88e3f014d6427565c01 (
plain)
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
|
"""Maintain a cache of stat() information on files.
There are functions to reset the cache or to selectively remove items.
"""
import os
from stat import *
# The cache.
# Keys are pathnames, values are `os.stat' outcomes.
#
cache = {}
def stat(path):
"""Stat a file, possibly out of the cache."""
if cache.has_key(path):
return cache[path]
cache[path] = ret = os.stat(path)
return ret
def reset():
"""Reset the cache completely."""
global cache
cache = {}
def forget(path):
"""Remove a given item from the cache, if it exists."""
if cache.has_key(path):
del cache[path]
def forget_prefix(prefix):
"""Remove all pathnames with a given prefix."""
n = len(prefix)
for path in cache.keys():
if path[:n] == prefix:
del cache[path]
def forget_dir(prefix):
"""Forget about a directory and all entries in it, but not about
entries in subdirectories."""
if prefix[-1:] == '/' and prefix <> '/':
prefix = prefix[:-1]
forget(prefix)
if prefix[-1:] <> '/':
prefix = prefix + '/'
n = len(prefix)
for path in cache.keys():
if path[:n] == prefix:
rest = path[n:]
if rest[-1:] == '/': rest = rest[:-1]
if '/' not in rest:
del cache[path]
def forget_except_prefix(prefix):
"""Remove all pathnames except with a given prefix.
Normally used with prefix = '/' after a chdir()."""
n = len(prefix)
for path in cache.keys():
if path[:n] <> prefix:
del cache[path]
def isdir(path):
"""Check for directory."""
try:
st = stat(path)
except os.error:
return 0
return S_ISDIR(st[ST_MODE])
|
