# author: Gordon McMillan; used and distributed with the author's permission.
# see http://www.mcmillan-inc.com/ for more information.
# Time-stamp: <03/02/09 22:18:11 smulloni>
import sys
import imp
import marshal
#=======================Owners==========================#
# An Owner does imports from a particular piece of turf
# That is, there's an Owner for each thing on sys.path
# There are owners for directories and .pyz files.
# There could be owners for zip files, or even URLs.
# A shadowpath (a dictionary mapping the names in
# sys.path to their owners) is used so that sys.path
# (or a package's __path__) is still a bunch of strings,
STRINGTYPE = type('')
class Owner:
def __init__(self, path):
self.path = path
def __str__(self):
return self.path
def getmod(self, nm):
return None
class DirOwner(Owner):
def __init__(self, path):
if path == '':
path = _os_getcwd()
if not pathisdir(path):
raise ValueError, "%s is not a directory" % path
Owner.__init__(self, path)
def getmod(self, nm, getsuffixes=imp.get_suffixes, loadco=marshal.loads, newmod=imp.new_module):
pth = _os_path_join(self.path, nm)
possibles = [(pth, 0, None)]
if pathisdir(pth):
possibles.insert(0, (_os_path_join(pth, '__init__'), 1, pth))
py = pyc = None
for pth, ispkg, pkgpth in possibles:
for ext, mode, typ in getsuffixes():
attempt = pth+ext
try:
st = _os_stat(attempt)
except:
pass
else:
if typ == imp.C_EXTENSION:
fp = open(attempt, 'rb')
mod = imp.load_module(nm, fp, attempt, (ext, mode, typ))
mod.__file__ = attempt
return mod
elif typ == imp.PY_SOURCE:
py = (attempt, st)
else:
pyc = (attempt, st)
if py or pyc:
break
if py is None and pyc is None:
return None
while 1:
if pyc is None or py and pyc[1][8] < py[1][8]:
try:
co = compile(open(py[0], 'r').read()+'\n', py[0], 'exec')
break
except SyntaxError, e:
print "Invalid syntax in %s" % py[0]
print e.args
raise
elif pyc:
stuff = open(pyc[0], 'rb').read()
try:
co = loadco(stuff[8:])
break
except (ValueError, EOFError):
pyc = None
else:
return None
mod = newmod(nm)
mod.__file__ = co.co_filename
if ispkg:
mod.__path__ = [pkgpth]
subimporter = PathImportDirector(mod.__path__)
mod.__importsub__ = subimporter.getmod
mod.__co__ = co
return mod
_globalownertypes = [
DirOwner,
Owner,
]
#===================Import Directors====================================#
# ImportDirectors live on the metapath
# There's one for builtins, one for frozen modules, and one for sys.path
# Windows gets one for modules gotten from the Registry
# Mac would have them for PY_RESOURCE modules etc.
# A generalization of Owner - their concept of "turf" is broader
class ImportDirector(Owner):
pass
class BuiltinImportDirector(ImportDirector):
def __init__(self):
self.path = 'Builtins'
def getmod(self, nm, isbuiltin=imp.is_builtin):
if isbuiltin(nm):
mod = imp.load_module(nm, None, nm, ('','',imp.C_BUILTIN))
return mod
return None
class FrozenImportDirector(ImportDirector):
def __init__(self):
self.path = 'FrozenModules'
def getmod(self, nm, isfrozen=imp.is_frozen):
if isfrozen(nm):
mod = imp.load_module(nm, None, nm, ('','',imp.PY_FROZEN))
if hasattr(mod, '__path__'):
mod.__importsub__ = lambda name, pname=nm, owner=self: owner.getmod(pname+'.'+name)
return mod
return None
class RegistryImportDirector(ImportDirector):
# for Windows only
def __init__(self):
self.path = "WindowsRegistry"
self.map = {}
try:
import win32api
## import win32con
except ImportError:
pass
else:
HKEY_CURRENT_USER = -2147483647
HKEY_LOCAL_MACHINE = -2147483646
KEY_ALL_ACCESS = 983103
subkey = r"Software\Python\PythonCore\%s\Modules" % sys.winver
for root in (HKEY_CURRENT_USER, HKEY_LOCAL_MACHINE):
try:
hkey = win32api.RegOpenKeyEx(root, subkey, 0, KEY_ALL_ACCESS)
except:
pass
else:
numsubkeys, numvalues, lastmodified = win32api.RegQueryInfoKey(hkey)
for i in range(numsubkeys):
subkeyname = win32api.RegEnumKey(hkey, i)
hskey = win32api.RegOpenKeyEx(hkey, subkeyname, 0, KEY_ALL_ACCESS)
val = win32api.RegQueryValueEx(hskey, '')
desc = getDescr(val[0])
self.map[subkeyname] = (val[0], desc)
hskey.Close()
hkey.Close()
break
def getmod(self, nm):
stuff = self.map.get(nm)
if stuff:
fnm, desc = stuff
fp = open(fnm, 'rb')
mod = imp.load_module(nm, fp, fnm, desc)
mod.__file__ = fnm
return mod
return None
class PathImportDirector(ImportDirector):
def __init__(self, pathlist=None, importers=None, ownertypes=None):
if pathlist is None:
self.path = sys.path
else:
self.path = pathlist
if ownertypes == None:
self.ownertypes = _globalownertypes
else:
self.ownertypes = ownertypes
if importers:
self.shadowpath = importers
else:
self.shadowpath = {}
self.inMakeOwner = 0
self.building = {}
def getmod(self, nm):
mod = None
for thing in self.path:
if type(thing) is STRINGTYPE:
owner = self.shadowpath.get(thing, -1)
if owner == -1:
owner = self.shadowpath[thing] = self.makeOwner(thing)
if owner:
mod = owner.getmod(nm)
else:
mod = thing.getmod(nm)
if mod:
break
return mod
def makeOwner(self, path):
if self.building.get(path):
return None
self.building[path] = 1
owner = None
for klass in self.ownertypes:
try:
# this may cause an import, which may cause recursion
# hence the protection
owner = klass(path)
except:
pass
else:
break
del self.building[path]
return owner
def getDescr(fnm):
ext = getpathext(fnm)
for (suffix, mode, typ) in imp.get_suffixes():
if suffix == ext:
return (suffix, mode, typ)
#=================ImportManager============================#
# The one-and-only ImportManager
# ie, the builtin import
UNTRIED = -1
class ImportManager:
# really the equivalent of builtin import
def __init__(self):
self.metapath = [
BuiltinImportDirector(),
FrozenImportDirector(),
RegistryImportDirector(),
PathImportDirector()
]
self.threaded = 0
self.rlock = None
self.locker = None
self.setThreaded()
def setThreaded(self):
thread = sys.modules.get('thread', None)
if thread and not self.threaded:
## print "iu setting threaded"
self.threaded = 1
self.rlock = thread.allocate_lock()
self._get_ident = thread.get_ident
def install(self):
import __builtin__
__builtin__.__import__ = self.importHook
__builtin__.reload = self.reloadHook
def importHook(self, name, globals=None, locals=None, fromlist=None):
# first see if we could be importing a relative name
#print "importHook(%s, %s, locals, %s)" % (name, globals['__name__'], fromlist)
_sys_modules_get = sys.modules.get
contexts = [None]
if globals:
importernm = globals.get('__name__', '')
if importernm:
if hasattr(_sys_modules_get(importernm), '__path__'):
contexts.insert(0,importernm)
else:
pkgnm = packagename(importernm)
if pkgnm:
contexts.insert(0,pkgnm)
# so contexts is [pkgnm, None] or just [None]
# now break the name being imported up so we get:
# a.b.c -> [a, b, c]
nmparts = namesplit(name)
_self_doimport = self.doimport
threaded = self.threaded
for context in contexts:
ctx = context
for i in range(len(nmparts)):
nm = nmparts[i]
#print " importHook trying %s in %s" % (nm, ctx)
if ctx:
fqname = ctx + '.' + nm
else:
fqname = nm
if threaded:
self._acquire()
mod = _sys_modules_get(fqname, UNTRIED)
if mod is UNTRIED:
try:
mod = _self_doimport(nm, ctx, fqname)
except:
if threaded:
self._release()
raise
if threaded:
self._release()
if mod:
ctx = fqname
else:
break
else:
# no break, point i beyond end
i = i + 1
if i:
break
if i<len(nmparts):
if ctx and hasattr(sys.modules[ctx], nmparts[i]):
#print "importHook done with %s %s %s (case 1)" % (name, globals['__name__'], fromlist)
return sys.modules[nmparts[0]]
del sys.modules[fqname]
raise ImportError, "No module named %s" % fqname
if fromlist is None:
#print "importHook done with %s %s %s (case 2)" % (name, globals['__name__'], fromlist)
if context:
return sys.modules[context+'.'+nmparts[0]]
return sys.modules[nmparts[0]]
bottommod = sys.modules[ctx]
if hasattr(bottommod, '__path__'):
fromlist = list(fromlist)
i = 0
while i < len(fromlist):
nm = fromlist[i]
if nm == '*':
fromlist[i:i+1] = list(getattr(bottommod, '__all__', []))
if i >= len(fromlist):
break
nm = fromlist[i]
i = i + 1
if not hasattr(bottommod, nm):
if threaded:
self._acquire()
try:
mod = self.doimport(nm, ctx, ctx+'.'+nm)
except:
pass
if threaded:
self._release()
#print "importHook done with %s %s %s (case 3)" % (name, globals['__name__'], fromlist)
return bottommod
def doimport(self, nm, parentnm, fqname):
# Not that nm is NEVER a dotted name at this point
#print "doimport(%s, %s, %s)" % (nm, parentnm, fqname)
if parentnm:
parent = sys.modules[parentnm]
if hasattr(parent, '__path__'):
importfunc = getattr(parent, '__importsub__', None)
if not importfunc:
subimporter = PathImportDirector(parent.__path__)
importfunc = parent.__importsub__ = subimporter.getmod
mod = importfunc(nm)
if mod:
setattr(parent, nm, mod)
else:
#print "..parent not a package"
return None
else:
# now we're dealing with an absolute import
for director in self.metapath:
mod = director.getmod(nm)
if mod:
break
if mod:
mod.__name__ = fqname
sys.modules[fqname] = mod
if hasattr(mod, '__co__'):
co = mod.__co__
del mod.__co__
exec co in mod.__dict__
if fqname == 'thread' and not self.threaded:
## print "thread detected!"
self.setThreaded()
else:
sys.modules[fqname] = None
#print "..found %s" % mod
return mod
def reloadHook(self, mod):
fqnm = mod.__name__
nm = namesplit(fqnm)[-1]
parentnm = packagename(fqnm)
newmod = self.doimport(nm, parentnm, fqnm)
mod.__dict__.update(newmod.__dict__)
## return newmod
def _acquire(self):
if self.rlock.locked():
if self.locker == self._get_ident():
self.lockcount = self.lockcount + 1
## print "_acquire incrementing lockcount to", self.lockcount
return
self.rlock.acquire()
self.locker = self._get_ident()
self.lockcount = 0
## print "_acquire first time!"
def _release(self):
if self.lockcount:
self.lockcount = self.lockcount - 1
## print "_release decrementing lockcount to", self.lockcount
else:
self.rlock.release()
self.locker = None
## print "_release releasing lock!"
#=========some helper functions=============================#
def packagename(s):
for i in range(len(s)-1, -1, -1):
if s[i] == '.':
break
else:
return ''
return s[:i]
def namesplit(s):
rslt = []
i = j = 0
for j in range(len(s)):
if s[j] == '.':
rslt.append(s[i:j])
i = j+1
if i < len(s):
rslt.append(s[i:])
return rslt
def getpathext(fnm):
for i in range(len(fnm)-1, -1, -1):
if fnm[i] == '.':
return fnm[i:]
return ''
def pathisdir(pathname):
"Local replacement for os.path.isdir()."
try:
s = _os_stat(pathname)
except OSError:
return None
return (s[0] & 0170000) == 0040000
_os_stat = _os_path_join = _os_getcwd = _os_path_dirname = None
def _os_bootstrap():
"Set up 'os' module replacement functions for use during import bootstrap."
names = sys.builtin_module_names
join = dirname = None
mindirlen = 0
if 'posix' in names:
sep = '/'
mindirlen = 1
from posix import stat,getcwd
elif 'nt' in names:
sep = '\\'
mindirlen = 3
from nt import stat,getcwd
elif 'dos' in names:
sep = '\\'
mindirlen = 3
from dos import stat,getcwd
elif 'os2' in names:
sep = '\\'
from os2 import stat,getcwd
elif 'mac' in names:
from mac import stat,getcwd
def join(a, b):
if a == '':
return b
path = s
if ':' not in a:
a = ':' + a
if a[-1:] != ':':
a = a + ':'
return a + b
else:
raise ImportError, 'no os specific module found'
if join is None:
def join(a, b, sep=sep):
if a == '':
return b
lastchar = a[-1:]
if lastchar == '/' or lastchar == sep:
return a + b
return a + sep + b
if dirname is None:
def dirname(a, sep=sep, mindirlen=mindirlen):
for i in range(len(a)-1, -1, -1):
c = a[i]
if c == '/' or c == sep:
if i < mindirlen:
return a[:i+1]
return a[:i]
return ''
global _os_stat
_os_stat = stat
global _os_path_join
_os_path_join = join
global _os_path_dirname
_os_path_dirname = dirname
global _os_getcwd
_os_getcwd = getcwd
_os_bootstrap()
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