waf

Utils.py (25647B)

---

 #!/usr/bin/env python
 # encoding: utf-8
 # Thomas Nagy, 2005-2018 (ita)
 
 """
 Utilities and platform-specific fixes
 
 The portability fixes try to provide a consistent behavior of the Waf API
 through Python versions 2.5 to 3.X and across different platforms (win32, linux, etc)
 """
 
 from __future__ import with_statement
 
 import atexit, os, sys, errno, inspect, re, datetime, platform, base64, signal, functools, time, shlex
 
 try:
 	import cPickle
 except ImportError:
 	import pickle as cPickle
 
 # leave this
 if os.name == 'posix' and sys.version_info[0] < 3:
 	try:
 		import subprocess32 as subprocess
 	except ImportError:
 		import subprocess
 else:
 	import subprocess
 
 try:
 	TimeoutExpired = subprocess.TimeoutExpired
 except AttributeError:
 	class TimeoutExpired(Exception):
 		pass
 
 from collections import deque, defaultdict
 
 try:
 	import _winreg as winreg
 except ImportError:
 	try:
 		import winreg
 	except ImportError:
 		winreg = None
 
 from waflib import Errors
 
 try:
 	from hashlib import sha1 as md5
 except ImportError:
 	# never fail to enable potential fixes from another module
 	pass
 
 try:
 	import threading
 except ImportError:
 	if not 'JOBS' in os.environ:
 		# no threading :-(
 		os.environ['JOBS'] = '1'
 
 	class threading(object):
 		"""
 		A fake threading class for platforms lacking the threading module.
 		Use ``waf -j1`` on those platforms
 		"""
 		pass
 	class Lock(object):
 		"""Fake Lock class"""
 		def acquire(self):
 			pass
 		def release(self):
 			pass
 	threading.Lock = threading.Thread = Lock
 
 SIG_NIL = 'SIG_NIL_SIG_NIL_'.encode()
 """Arbitrary null value for hashes. Modify this value according to the hash function in use"""
 
 O644 = 420
 """Constant representing the permissions for regular files (0644 raises a syntax error on python 3)"""
 
 O755 = 493
 """Constant representing the permissions for executable files (0755 raises a syntax error on python 3)"""
 
 rot_chr = ['\\', '|', '/', '-']
 "List of characters to use when displaying the throbber (progress bar)"
 
 rot_idx = 0
 "Index of the current throbber character (progress bar)"
 
 class ordered_iter_dict(dict):
 	"""Ordered dictionary that provides iteration from the most recently inserted keys first"""
 	def __init__(self, *k, **kw):
 		self.lst = deque()
 		dict.__init__(self, *k, **kw)
 	def clear(self):
 		dict.clear(self)
 		self.lst = deque()
 	def __setitem__(self, key, value):
 		if key in dict.keys(self):
 			self.lst.remove(key)
 		dict.__setitem__(self, key, value)
 		self.lst.append(key)
 	def __delitem__(self, key):
 		dict.__delitem__(self, key)
 		try:
 			self.lst.remove(key)
 		except ValueError:
 			pass
 	def __iter__(self):
 		return reversed(self.lst)
 	def keys(self):
 		return reversed(self.lst)
 
 class lru_node(object):
 	"""
 	Used by :py:class:`waflib.Utils.lru_cache`
 	"""
 	__slots__ = ('next', 'prev', 'key', 'val')
 	def __init__(self):
 		self.next = self
 		self.prev = self
 		self.key = None
 		self.val = None
 
 class lru_cache(object):
 	"""
 	A simple least-recently used cache with lazy allocation
 	"""
 	__slots__ = ('maxlen', 'table', 'head')
 	def __init__(self, maxlen=100):
 		self.maxlen = maxlen
 		"""
 		Maximum amount of elements in the cache
 		"""
 		self.table = {}
 		"""
 		Mapping key-value
 		"""
 		self.head = lru_node()
 		self.head.next = self.head
 		self.head.prev = self.head
 
 	def __getitem__(self, key):
 		node = self.table[key]
 		# assert(key==node.key)
 		if node is self.head:
 			return node.val
 
 		# detach the node found
 		node.prev.next = node.next
 		node.next.prev = node.prev
 
 		# replace the head
 		node.next = self.head.next
 		node.prev = self.head
 		self.head = node.next.prev = node.prev.next = node
 
 		return node.val
 
 	def __setitem__(self, key, val):
 		if key in self.table:
 			# update the value for an existing key
 			node = self.table[key]
 			node.val = val
 			self.__getitem__(key)
 		else:
 			if len(self.table) < self.maxlen:
 				# the very first item is unused until the maximum is reached
 				node = lru_node()
 				node.prev = self.head
 				node.next = self.head.next
 				node.prev.next = node.next.prev = node
 			else:
 				node = self.head = self.head.next
 				try:
 					# that's another key
 					del self.table[node.key]
 				except KeyError:
 					pass
 
 			node.key = key
 			node.val = val
 			self.table[key] = node
 
 class lazy_generator(object):
 	def __init__(self, fun, params):
 		self.fun = fun
 		self.params = params
 
 	def __iter__(self):
 		return self
 
 	def __next__(self):
 		try:
 			it = self.it
 		except AttributeError:
 			it = self.it = self.fun(*self.params)
 		return next(it)
 
 	next = __next__
 
 is_win32 = os.sep == '\\' or sys.platform == 'win32' or os.name == 'nt' # msys2
 """
 Whether this system is a Windows series
 """
 
 def readf(fname, m='r', encoding='latin-1'):
 	"""
 	Reads an entire file into a string. See also :py:meth:`waflib.Node.Node.readf`::
 
 		def build(ctx):
 			from waflib import Utils
 			txt = Utils.readf(self.path.find_node('wscript').abspath())
 			txt = ctx.path.find_node('wscript').read()
 
 	:type  fname: string
 	:param fname: Path to file
 	:type  m: string
 	:param m: Open mode
 	:type encoding: string
 	:param encoding: encoding value, only used for python 3
 	:rtype: string
 	:return: Content of the file
 	"""
 
 	if sys.hexversion > 0x3000000 and not 'b' in m:
 		m += 'b'
 		with open(fname, m) as f:
 			txt = f.read()
 		if encoding:
 			txt = txt.decode(encoding)
 		else:
 			txt = txt.decode()
 	else:
 		with open(fname, m) as f:
 			txt = f.read()
 	return txt
 
 def writef(fname, data, m='w', encoding='latin-1'):
 	"""
 	Writes an entire file from a string.
 	See also :py:meth:`waflib.Node.Node.writef`::
 
 		def build(ctx):
 			from waflib import Utils
 			txt = Utils.writef(self.path.make_node('i_like_kittens').abspath(), 'some data')
 			self.path.make_node('i_like_kittens').write('some data')
 
 	:type  fname: string
 	:param fname: Path to file
 	:type   data: string
 	:param  data: The contents to write to the file
 	:type  m: string
 	:param m: Open mode
 	:type encoding: string
 	:param encoding: encoding value, only used for python 3
 	"""
 	if sys.hexversion > 0x3000000 and not 'b' in m:
 		data = data.encode(encoding)
 		m += 'b'
 	with open(fname, m) as f:
 		f.write(data)
 
 def h_file(fname):
 	"""
 	Computes a hash value for a file by using md5. Use the md5_tstamp
 	extension to get faster build hashes if necessary.
 
 	:type fname: string
 	:param fname: path to the file to hash
 	:return: hash of the file contents
 	:rtype: string or bytes
 	"""
 	m = md5()
 	with open(fname, 'rb') as f:
 		while fname:
 			fname = f.read(200000)
 			m.update(fname)
 	return m.digest()
 
 def readf_win32(f, m='r', encoding='latin-1'):
 	flags = os.O_NOINHERIT | os.O_RDONLY
 	if 'b' in m:
 		flags |= os.O_BINARY
 	if '+' in m:
 		flags |= os.O_RDWR
 	try:
 		fd = os.open(f, flags)
 	except OSError:
 		raise IOError('Cannot read from %r' % f)
 
 	if sys.hexversion > 0x3000000 and not 'b' in m:
 		m += 'b'
 		with os.fdopen(fd, m) as f:
 			txt = f.read()
 		if encoding:
 			txt = txt.decode(encoding)
 		else:
 			txt = txt.decode()
 	else:
 		with os.fdopen(fd, m) as f:
 			txt = f.read()
 	return txt
 
 def writef_win32(f, data, m='w', encoding='latin-1'):
 	if sys.hexversion > 0x3000000 and not 'b' in m:
 		data = data.encode(encoding)
 		m += 'b'
 	flags = os.O_CREAT | os.O_TRUNC | os.O_WRONLY | os.O_NOINHERIT
 	if 'b' in m:
 		flags |= os.O_BINARY
 	if '+' in m:
 		flags |= os.O_RDWR
 	try:
 		fd = os.open(f, flags)
 	except OSError:
 		raise OSError('Cannot write to %r' % f)
 	with os.fdopen(fd, m) as f:
 		f.write(data)
 
 def h_file_win32(fname):
 	try:
 		fd = os.open(fname, os.O_BINARY | os.O_RDONLY | os.O_NOINHERIT)
 	except OSError:
 		raise OSError('Cannot read from %r' % fname)
 	m = md5()
 	with os.fdopen(fd, 'rb') as f:
 		while fname:
 			fname = f.read(200000)
 			m.update(fname)
 	return m.digest()
 
 # always save these
 readf_unix = readf
 writef_unix = writef
 h_file_unix = h_file
 if hasattr(os, 'O_NOINHERIT') and sys.hexversion < 0x3040000:
 	# replace the default functions
 	readf = readf_win32
 	writef = writef_win32
 	h_file = h_file_win32
 
 try:
 	x = ''.encode('hex')
 except LookupError:
 	import binascii
 	def to_hex(s):
 		ret = binascii.hexlify(s)
 		if not isinstance(ret, str):
 			ret = ret.decode('utf-8')
 		return ret
 else:
 	def to_hex(s):
 		return s.encode('hex')
 
 to_hex.__doc__ = """
 Return the hexadecimal representation of a string
 
 :param s: string to convert
 :type s: string
 """
 
 def listdir_win32(s):
 	"""
 	Lists the contents of a folder in a portable manner.
 	On Win32, returns the list of drive letters: ['C:', 'X:', 'Z:'] when an empty string is given.
 
 	:type s: string
 	:param s: a string, which can be empty on Windows
 	"""
 	if not s:
 		try:
 			import ctypes
 		except ImportError:
 			# there is nothing much we can do
 			return [x + ':\\' for x in 'ABCDEFGHIJKLMNOPQRSTUVWXYZ']
 		else:
 			dlen = 4 # length of "?:\\x00"
 			maxdrives = 26
 			buf = ctypes.create_string_buffer(maxdrives * dlen)
 			ndrives = ctypes.windll.kernel32.GetLogicalDriveStringsA(maxdrives*dlen, ctypes.byref(buf))
 			return [ str(buf.raw[4*i:4*i+2].decode('ascii')) for i in range(int(ndrives/dlen)) ]
 
 	if len(s) == 2 and s[1] == ":":
 		s += os.sep
 
 	if not os.path.isdir(s):
 		e = OSError('%s is not a directory' % s)
 		e.errno = errno.ENOENT
 		raise e
 	return os.listdir(s)
 
 listdir = os.listdir
 if is_win32:
 	listdir = listdir_win32
 
 def num2ver(ver):
 	"""
 	Converts a string, tuple or version number into an integer. The number is supposed to have at most 4 digits::
 
 		from waflib.Utils import num2ver
 		num2ver('1.3.2') == num2ver((1,3,2)) == num2ver((1,3,2,0))
 
 	:type ver: string or tuple of numbers
 	:param ver: a version number
 	"""
 	if isinstance(ver, str):
 		ver = tuple(ver.split('.'))
 	if isinstance(ver, tuple):
 		ret = 0
 		for i in range(4):
 			if i < len(ver):
 				ret += 256**(3 - i) * int(ver[i])
 		return ret
 	return ver
 
 def to_list(val):
 	"""
 	Converts a string argument to a list by splitting it by spaces.
 	Returns the object if not a string::
 
 		from waflib.Utils import to_list
 		lst = to_list('a b c d')
 
 	:param val: list of string or space-separated string
 	:rtype: list
 	:return: Argument converted to list
 	"""
 	if isinstance(val, str):
 		return val.split()
 	else:
 		return val
 
 def console_encoding():
 	try:
 		import ctypes
 	except ImportError:
 		pass
 	else:
 		try:
 			codepage = ctypes.windll.kernel32.GetConsoleCP()
 		except AttributeError:
 			pass
 		else:
 			if codepage:
 				if 65001 == codepage and sys.version_info < (3, 3):
 					return 'utf-8'
 				return 'cp%d' % codepage
 	return sys.stdout.encoding or ('cp1252' if is_win32 else 'latin-1')
 
 def split_path_unix(path):
 	return path.split('/')
 
 def split_path_cygwin(path):
 	if path.startswith('//'):
 		ret = path.split('/')[2:]
 		ret[0] = '/' + ret[0]
 		return ret
 	return path.split('/')
 
 re_sp = re.compile('[/\\\\]+')
 def split_path_win32(path):
 	if path.startswith('\\\\'):
 		ret = re_sp.split(path)[1:]
 		ret[0] = '\\\\' + ret[0]
 		if ret[0] == '\\\\?':
 			return ret[1:]
 		return ret
 	return re_sp.split(path)
 
 msysroot = None
 def split_path_msys(path):
 	if path.startswith(('/', '\\')) and not path.startswith(('//', '\\\\')):
 		# msys paths can be in the form /usr/bin
 		global msysroot
 		if not msysroot:
 			# msys has python 2.7 or 3, so we can use this
 			msysroot = subprocess.check_output(['cygpath', '-w', '/']).decode(sys.stdout.encoding or 'latin-1')
 			msysroot = msysroot.strip()
 		path = os.path.normpath(msysroot + os.sep + path)
 	return split_path_win32(path)
 
 if sys.platform == 'cygwin':
 	split_path = split_path_cygwin
 elif is_win32:
 	# Consider this an MSYSTEM environment if $MSYSTEM is set and python
 	# reports is executable from a unix like path on a windows host.
 	if os.environ.get('MSYSTEM') and sys.executable.startswith('/'):
 		split_path = split_path_msys
 	else:
 		split_path = split_path_win32
 else:
 	split_path = split_path_unix
 
 split_path.__doc__ = """
 Splits a path by / or \\; do not confuse this function with with ``os.path.split``
 
 :type  path: string
 :param path: path to split
 :return:     list of string
 """
 
 def check_dir(path):
 	"""
 	Ensures that a directory exists (similar to ``mkdir -p``).
 
 	:type  path: string
 	:param path: Path to directory
 	:raises: :py:class:`waflib.Errors.WafError` if the folder cannot be added.
 	"""
 	if not os.path.isdir(path):
 		try:
 			os.makedirs(path)
 		except OSError as e:
 			if not os.path.isdir(path):
 				raise Errors.WafError('Cannot create the folder %r' % path, ex=e)
 
 def check_exe(name, env=None):
 	"""
 	Ensures that a program exists
 
 	:type name: string
 	:param name: path to the program
 	:param env: configuration object
 	:type env: :py:class:`waflib.ConfigSet.ConfigSet`
 	:return: path of the program or None
 	:raises: :py:class:`waflib.Errors.WafError` if the folder cannot be added.
 	"""
 	if not name:
 		raise ValueError('Cannot execute an empty string!')
 	def is_exe(fpath):
 		return os.path.isfile(fpath) and os.access(fpath, os.X_OK)
 
 	fpath, fname = os.path.split(name)
 	if fpath and is_exe(name):
 		return os.path.abspath(name)
 	else:
 		env = env or os.environ
 		for path in env['PATH'].split(os.pathsep):
 			path = path.strip('"')
 			exe_file = os.path.join(path, name)
 			if is_exe(exe_file):
 				return os.path.abspath(exe_file)
 	return None
 
 def def_attrs(cls, **kw):
 	"""
 	Sets default attributes on a class instance
 
 	:type cls: class
 	:param cls: the class to update the given attributes in.
 	:type kw: dict
 	:param kw: dictionary of attributes names and values.
 	"""
 	for k, v in kw.items():
 		if not hasattr(cls, k):
 			setattr(cls, k, v)
 
 def quote_define_name(s):
 	"""
 	Converts a string into an identifier suitable for C defines.
 
 	:type  s: string
 	:param s: String to convert
 	:rtype: string
 	:return: Identifier suitable for C defines
 	"""
 	fu = re.sub('[^a-zA-Z0-9]', '_', s)
 	fu = re.sub('_+', '_', fu)
 	fu = fu.upper()
 	return fu
 
 # shlex.quote didn't exist until python 3.3. Prior to that it was a non-documented
 # function in pipes.
 try:
 	shell_quote = shlex.quote
 except AttributeError:
 	import pipes
 	shell_quote = pipes.quote
 
 def shell_escape(cmd):
 	"""
 	Escapes a command:
 	['ls', '-l', 'arg space'] -> ls -l 'arg space'
 	"""
 	if isinstance(cmd, str):
 		return cmd
 	return ' '.join(shell_quote(x) for x in cmd)
 
 def h_list(lst):
 	"""
 	Hashes lists of ordered data.
 
 	Using hash(tup) for tuples would be much more efficient,
 	but Python now enforces hash randomization
 
 	:param lst: list to hash
 	:type lst: list of strings
 	:return: hash of the list
 	"""
 	return md5(repr(lst).encode()).digest()
 
 if sys.hexversion < 0x3000000:
 	def h_list_python2(lst):
 		return md5(repr(lst)).digest()
 	h_list_python2.__doc__ = h_list.__doc__
 	h_list = h_list_python2
 
 def h_fun(fun):
 	"""
 	Hash functions
 
 	:param fun: function to hash
 	:type  fun: function
 	:return: hash of the function
 	:rtype: string or bytes
 	"""
 	try:
 		return fun.code
 	except AttributeError:
 		if isinstance(fun, functools.partial):
 			code = list(fun.args)
 			# The method items() provides a sequence of tuples where the first element
 			# represents an optional argument of the partial function application
 			#
 			# The sorting result outcome will be consistent because:
 			# 1. tuples are compared in order of their elements
 			# 2. optional argument namess are unique
 			code.extend(sorted(fun.keywords.items()))
 			code.append(h_fun(fun.func))
 			fun.code = h_list(code)
 			return fun.code
 		try:
 			h = inspect.getsource(fun)
 		except EnvironmentError:
 			h = 'nocode'
 		try:
 			fun.code = h
 		except AttributeError:
 			pass
 		return h
 
 def h_cmd(ins):
 	"""
 	Hashes objects recursively
 
 	:param ins: input object
 	:type ins: string or list or tuple or function
 	:rtype: string or bytes
 	"""
 	# this function is not meant to be particularly fast
 	if isinstance(ins, str):
 		# a command is either a string
 		ret = ins
 	elif isinstance(ins, list) or isinstance(ins, tuple):
 		# or a list of functions/strings
 		ret = str([h_cmd(x) for x in ins])
 	else:
 		# or just a python function
 		ret = str(h_fun(ins))
 	if sys.hexversion > 0x3000000:
 		ret = ret.encode('latin-1', 'xmlcharrefreplace')
 	return ret
 
 reg_subst = re.compile(r"(\\\\)|(\$\$)|\$\{([^}]+)\}")
 def subst_vars(expr, params):
 	"""
 	Replaces ${VAR} with the value of VAR taken from a dict or a config set::
 
 		from waflib import Utils
 		s = Utils.subst_vars('${PREFIX}/bin', env)
 
 	:type  expr: string
 	:param expr: String to perform substitution on
 	:param params: Dictionary or config set to look up variable values.
 	"""
 	def repl_var(m):
 		if m.group(1):
 			return '\\'
 		if m.group(2):
 			return '$'
 		try:
 			# ConfigSet instances may contain lists
 			return params.get_flat(m.group(3))
 		except AttributeError:
 			return params[m.group(3)]
 		# if you get a TypeError, it means that 'expr' is not a string...
 		# Utils.subst_vars(None, env)  will not work
 	return reg_subst.sub(repl_var, expr)
 
 def destos_to_binfmt(key):
 	"""
 	Returns the binary format based on the unversioned platform name,
 	and defaults to ``elf`` if nothing is found.
 
 	:param key: platform name
 	:type  key: string
 	:return: string representing the binary format
 	"""
 	if key == 'darwin':
 		return 'mac-o'
 	elif key in ('win32', 'cygwin', 'uwin', 'msys'):
 		return 'pe'
 	return 'elf'
 
 def unversioned_sys_platform():
 	"""
 	Returns the unversioned platform name.
 	Some Python platform names contain versions, that depend on
 	the build environment, e.g. linux2, freebsd6, etc.
 	This returns the name without the version number. Exceptions are
 	os2 and win32, which are returned verbatim.
 
 	:rtype: string
 	:return: Unversioned platform name
 	"""
 	s = sys.platform
 	if s.startswith('java'):
 		# The real OS is hidden under the JVM.
 		from java.lang import System
 		s = System.getProperty('os.name')
 		# see http://lopica.sourceforge.net/os.html for a list of possible values
 		if s == 'Mac OS X':
 			return 'darwin'
 		elif s.startswith('Windows '):
 			return 'win32'
 		elif s == 'OS/2':
 			return 'os2'
 		elif s == 'HP-UX':
 			return 'hp-ux'
 		elif s in ('SunOS', 'Solaris'):
 			return 'sunos'
 		else: s = s.lower()
 
 	# powerpc == darwin for our purposes
 	if s == 'powerpc':
 		return 'darwin'
 	if s == 'win32' or s == 'os2':
 		return s
 	if s == 'cli' and os.name == 'nt':
 		# ironpython is only on windows as far as we know
 		return 'win32'
 	return re.split(r'\d+$', s)[0]
 
 def nada(*k, **kw):
 	"""
 	Does nothing
 
 	:return: None
 	"""
 	pass
 
 class Timer(object):
 	"""
 	Simple object for timing the execution of commands.
 	Its string representation is the duration::
 
 		from waflib.Utils import Timer
 		timer = Timer()
 		a_few_operations()
 		s = str(timer)
 	"""
 	def __init__(self):
 		self.start_time = self.now()
 
 	def __str__(self):
 		delta = self.now() - self.start_time
 		if not isinstance(delta, datetime.timedelta):
 			delta = datetime.timedelta(seconds=delta)
 		days = delta.days
 		hours, rem = divmod(delta.seconds, 3600)
 		minutes, seconds = divmod(rem, 60)
 		seconds += delta.microseconds * 1e-6
 		result = ''
 		if days:
 			result += '%dd' % days
 		if days or hours:
 			result += '%dh' % hours
 		if days or hours or minutes:
 			result += '%dm' % minutes
 		return '%s%.3fs' % (result, seconds)
 
 	def now(self):
 		return datetime.datetime.utcnow()
 
 	if hasattr(time, 'perf_counter'):
 		def now(self):
 			return time.perf_counter()
 
 def read_la_file(path):
 	"""
 	Reads property files, used by msvc.py
 
 	:param path: file to read
 	:type path: string
 	"""
 	sp = re.compile(r'^([^=]+)=\'(.*)\'$')
 	dc = {}
 	for line in readf(path).splitlines():
 		try:
 			_, left, right, _ = sp.split(line.strip())
 			dc[left] = right
 		except ValueError:
 			pass
 	return dc
 
 def run_once(fun):
 	"""
 	Decorator: let a function cache its results, use like this::
 
 		@run_once
 		def foo(k):
 			return 345*2343
 
 	.. note:: in practice this can cause memory leaks, prefer a :py:class:`waflib.Utils.lru_cache`
 
 	:param fun: function to execute
 	:type fun: function
 	:return: the return value of the function executed
 	"""
 	cache = {}
 	def wrap(*k):
 		try:
 			return cache[k]
 		except KeyError:
 			ret = fun(*k)
 			cache[k] = ret
 			return ret
 	wrap.__cache__ = cache
 	wrap.__name__ = fun.__name__
 	return wrap
 
 def get_registry_app_path(key, filename):
 	"""
 	Returns the value of a registry key for an executable
 
 	:type key: string
 	:type filename: list of string
 	"""
 	if not winreg:
 		return None
 	try:
 		result = winreg.QueryValue(key, "Software\\Microsoft\\Windows\\CurrentVersion\\App Paths\\%s.exe" % filename[0])
 	except OSError:
 		pass
 	else:
 		if os.path.isfile(result):
 			return result
 
 def lib64():
 	"""
 	Guess the default ``/usr/lib`` extension for 64-bit applications
 
 	:return: '64' or ''
 	:rtype: string
 	"""
 	# default settings for /usr/lib
 	if os.sep == '/':
 		if platform.architecture()[0] == '64bit':
 			if os.path.exists('/usr/lib64') and not os.path.exists('/usr/lib32'):
 				return '64'
 	return ''
 
 def loose_version(ver_str):
 	# private for the time being!
 	# see #2402
 	lst = re.split(r'([.]|\\d+|[a-zA-Z])', ver_str)
 	ver = []
 	for i, val in enumerate(lst):
 		try:
 			ver.append(int(val))
 		except ValueError:
 			if val != '.':
 				ver.append(val)
 	return ver
 
 def sane_path(p):
 	# private function for the time being!
 	return os.path.abspath(os.path.expanduser(p))
 
 process_pool = []
 """
 List of processes started to execute sub-process commands
 """
 
 def get_process():
 	"""
 	Returns a process object that can execute commands as sub-processes
 
 	:rtype: subprocess.Popen
 	"""
 	try:
 		return process_pool.pop()
 	except IndexError:
 		filepath = os.path.dirname(os.path.abspath(__file__)) + os.sep + 'processor.py'
 		cmd = [sys.executable, '-c', readf(filepath)]
 		return subprocess.Popen(cmd, stdout=subprocess.PIPE, stdin=subprocess.PIPE, bufsize=0, close_fds=not is_win32)
 
 def run_prefork_process(cmd, kwargs, cargs):
 	"""
 	Delegates process execution to a pre-forked process instance.
 	"""
 	if not kwargs.get('env'):
 		kwargs['env'] = dict(os.environ)
 	try:
 		obj = base64.b64encode(cPickle.dumps([cmd, kwargs, cargs]))
 	except (TypeError, AttributeError):
 		return run_regular_process(cmd, kwargs, cargs)
 
 	proc = get_process()
 	if not proc:
 		return run_regular_process(cmd, kwargs, cargs)
 
 	proc.stdin.write(obj)
 	proc.stdin.write('\n'.encode())
 	proc.stdin.flush()
 	obj = proc.stdout.readline()
 	if not obj:
 		raise OSError('Preforked sub-process %r died' % proc.pid)
 
 	process_pool.append(proc)
 	lst = cPickle.loads(base64.b64decode(obj))
 	# Jython wrapper failures (bash/execvp)
 	assert len(lst) == 5
 	ret, out, err, ex, trace = lst
 	if ex:
 		if ex == 'OSError':
 			raise OSError(trace)
 		elif ex == 'ValueError':
 			raise ValueError(trace)
 		elif ex == 'TimeoutExpired':
 			exc = TimeoutExpired(cmd, timeout=cargs['timeout'], output=out)
 			exc.stderr = err
 			raise exc
 		else:
 			raise Exception(trace)
 	return ret, out, err
 
 def lchown(path, user=-1, group=-1):
 	"""
 	Change the owner/group of a path, raises an OSError if the
 	ownership change fails.
 
 	:param user: user to change
 	:type user: int or str
 	:param group: group to change
 	:type group: int or str
 	"""
 	if isinstance(user, str):
 		import pwd
 		entry = pwd.getpwnam(user)
 		if not entry:
 			raise OSError('Unknown user %r' % user)
 		user = entry[2]
 	if isinstance(group, str):
 		import grp
 		entry = grp.getgrnam(group)
 		if not entry:
 			raise OSError('Unknown group %r' % group)
 		group = entry[2]
 	return os.lchown(path, user, group)
 
 def run_regular_process(cmd, kwargs, cargs={}):
 	"""
 	Executes a subprocess command by using subprocess.Popen
 	"""
 	proc = subprocess.Popen(cmd, **kwargs)
 	if kwargs.get('stdout') or kwargs.get('stderr'):
 		try:
 			out, err = proc.communicate(**cargs)
 		except TimeoutExpired:
 			if kwargs.get('start_new_session') and hasattr(os, 'killpg'):
 				os.killpg(proc.pid, signal.SIGKILL)
 			else:
 				proc.kill()
 			out, err = proc.communicate()
 			exc = TimeoutExpired(proc.args, timeout=cargs['timeout'], output=out)
 			exc.stderr = err
 			raise exc
 		status = proc.returncode
 	else:
 		out, err = (None, None)
 		try:
 			status = proc.wait(**cargs)
 		except TimeoutExpired as e:
 			if kwargs.get('start_new_session') and hasattr(os, 'killpg'):
 				os.killpg(proc.pid, signal.SIGKILL)
 			else:
 				proc.kill()
 			proc.wait()
 			raise e
 	return status, out, err
 
 def run_process(cmd, kwargs, cargs={}):
 	"""
 	Executes a subprocess by using a pre-forked process when possible
 	or falling back to subprocess.Popen. See :py:func:`waflib.Utils.run_prefork_process`
 	and :py:func:`waflib.Utils.run_regular_process`
 	"""
 	if kwargs.get('stdout') and kwargs.get('stderr'):
 		return run_prefork_process(cmd, kwargs, cargs)
 	else:
 		return run_regular_process(cmd, kwargs, cargs)
 
 def alloc_process_pool(n, force=False):
 	"""
 	Allocates an amount of processes to the default pool so its size is at least *n*.
 	It is useful to call this function early so that the pre-forked
 	processes use as little memory as possible.
 
 	:param n: pool size
 	:type n: integer
 	:param force: if True then *n* more processes are added to the existing pool
 	:type force: bool
 	"""
 	# mandatory on python2, unnecessary on python >= 3.2
 	global run_process, get_process, alloc_process_pool
 	if not force:
 		n = max(n - len(process_pool), 0)
 	try:
 		lst = [get_process() for x in range(n)]
 	except OSError:
 		run_process = run_regular_process
 		get_process = alloc_process_pool = nada
 	else:
 		for x in lst:
 			process_pool.append(x)
 
 def atexit_pool():
 	for k in process_pool:
 		try:
 			os.kill(k.pid, 9)
 		except OSError:
 			pass
 		else:
 			k.wait()
 # see #1889
 if (sys.hexversion<0x207000f and not is_win32) or sys.hexversion>=0x306000f:
 	atexit.register(atexit_pool)
 
 if os.environ.get('WAF_NO_PREFORK') or sys.platform == 'cli' or not sys.executable:
 	run_process = run_regular_process
 	get_process = alloc_process_pool = nada