# Module 'maccache'
#
# Maintain a cache of listdir(), isdir(), isfile() or exists() outcomes.
# XXX Should merge with module statcache
import os
# The cache.
# Keys are absolute pathnames;
# values are 0 (nothing), 1 (file) or [...] (dir).
#
cache = {}
# Current working directory.
#
cwd = os.getcwd()
# Constants.
#
NONE = 0
FILE = 1
LISTTYPE = type([])
def _stat(name):
name = os.path.join(cwd, name)
if cache.has_key(name):
return cache[name]
if os.path.isfile(name):
cache[name] = FILE
return FILE
try:
list = os.listdir(name)
except:
cache[name] = NONE
return NONE
cache[name] = list
if name[-1:] == ':': cache[name[:-1]] = list
else: cache[name+':'] = list
return list
def isdir(name):
st = _stat(name)
return type(st) == LISTTYPE
def isfile(name):
st = _stat(name)
return st == FILE
def exists(name):
st = _stat(name)
return st <> NONE
def listdir(name):
st = _stat(name)
if type(st) == LISTTYPE:
return st
else:
raise RuntimeError, 'list non-directory'
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