4 # Permission is hereby granted, free of charge, to any person obtaining
5 # a copy of this software and associated documentation files (the
6 # "Software"), to deal in the Software without restriction, including
7 # without limitation the rights to use, copy, modify, merge, publish,
8 # distribute, sublicense, and/or sell copies of the Software, and to
9 # permit persons to whom the Software is furnished to do so, subject to
10 # the following conditions:
12 # The above copyright notice and this permission notice shall be included
13 # in all copies or substantial portions of the Software.
15 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
16 # KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
17 # WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
19 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
20 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
21 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 SCons compatibility package for old Python versions
27 This subpackage holds modules that provide backwards-compatible
28 implementations of various things that we'd like to use in SCons but which
29 only show up in later versions of Python than the early, old version(s)
32 Other code will not generally reference things in this package through
33 the SCons.compat namespace. The modules included here add things to
34 the builtins namespace or the global module list so that the rest
35 of our code can use the objects and names imported here regardless of
38 Simply enough, things that go in the builtins name space come from
39 our _scons_builtins module.
41 The rest of the things here will be in individual compatibility modules
42 that are either: 1) suitably modified copies of the future modules that
43 we want to use; or 2) backwards compatible re-implementations of the
44 specific portions of a future module's API that we want to use.
46 GENERAL WARNINGS: Implementations of functions in the SCons.compat
47 modules are *NOT* guaranteed to be fully compliant with these functions in
48 later versions of Python. We are only concerned with adding functionality
49 that we actually use in SCons, so be wary if you lift this code for
50 other uses. (That said, making these more nearly the same as later,
51 official versions is still a desirable goal, we just don't need to be
54 We name the compatibility modules with an initial '_scons_' (for example,
55 _scons_subprocess.py is our compatibility module for subprocess) so
56 that we can still try to import the real module name and fall back to
57 our compatibility module if we get an ImportError. The import_as()
58 function defined below loads the module as the "real" name (without the
59 '_scons'), after which all of the "import {module}" statements in the
60 rest of our code will find our pre-loaded compatibility module.
63 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
65 def import_as(module, name):
67 Imports the specified module (from our local directory) as the
68 specified name, returning the loaded module object.
72 dir = os.path.split(__file__)[0]
73 file, filename, suffix_mode_type = imp.find_module(module, [dir])
74 return imp.load_module(name, file, filename, suffix_mode_type)
80 # Use the "imp" module to protect the import from fixers.
83 _builtin = imp.load_module('__builtin__',
84 *imp.find_module('__builtin__'))
85 sys.modules['builtins'] = _builtin
88 import _scons_builtins
94 # Pre-2.5 Python has no hashlib module.
96 import_as('_scons_hashlib', 'hashlib')
98 # If we failed importing our compatibility module, it probably
99 # means this version of Python has no md5 module. Don't do
100 # anything and let the higher layer discover this fact, so it
101 # can fall back to using timestamp.
107 # Pre-2.4 Python has no native set type
108 import_as('_scons_sets', 'sets')
109 import builtins, sets
110 builtins.set = sets.Set
116 # Pre-2.4 Python has no collections module.
117 import_as('_scons_collections', 'collections')
119 # Use the "imp" module to protect the imports below from fixers.
123 except AttributeError:
124 _UserDict = imp.load_module('UserDict', *imp.find_module('UserDict'))
125 collections.UserDict = _UserDict.UserDict
129 except AttributeError:
130 _UserList = imp.load_module('UserList', *imp.find_module('UserList'))
131 collections.UserList = _UserList.UserList
134 collections.UserString
135 except AttributeError:
136 _UserString = imp.load_module('UserString',
137 *imp.find_module('UserString'))
138 collections.UserString = _UserString.UserString
145 dbm = import_as('_scons_dbm', 'dbm')
148 except AttributeError:
149 # Pre-3.0 Python has no dbm.whichdb function.
151 dbm.whichdb = whichdb.whichdb
158 except AttributeError:
159 # Pre-2.2 Python has no fnmatch.filter() function.
160 def filter(names, pat):
161 """Return the subset of the list NAMES that match PAT"""
164 pat = os.path.normcase(pat)
165 if pat not in fnmatch._cache:
167 res = fnmatch.translate(pat)
168 fnmatch._cache[pat] = re.compile(res)
169 match = fnmatch._cache[pat].match
170 if os.path is posixpath:
171 # normcase on posix is NOP. Optimize it away from the loop.
177 if match(os.path.normcase(name)):
180 fnmatch.filter = filter
186 # Pre-2.6 Python has no io module.
187 import_as('_scons_io', 'io')
192 # Pre-2.3 Python has no itertools module.
193 import_as('_scons_itertools', 'itertools')
195 # If we need the compatibility version of textwrap, it must be imported
196 # before optparse, which uses it.
200 # Pre-2.3 Python has no textwrap module.
201 import_as('_scons_textwrap', 'textwrap')
206 # Pre-2.3 Python has no optparse module.
207 import_as('_scons_optparse', 'optparse')
212 except AttributeError:
213 # Pre-2.4 Python has no os.devnull attribute
215 _names = sys.builtin_module_names
216 if 'posix' in _names:
217 os.devnull = '/dev/null'
220 os.path.devnull = os.devnull
223 except AttributeError:
224 # Pre-2.4 Python has no os.path.lexists function
226 return os.path.exists(path) or os.path.islink(path)
227 os.path.lexists = lexists
231 # Use the "imp" module to protect the import from fixers.
233 _cPickle = imp.load_module('cPickle', *imp.find_module('cPickle'))
234 except ImportError, e:
235 # The "cPickle" module has already been eliminated in favor of
236 # having "import pickle" import the fast version when available.
240 sys.modules['pickle'] = _cPickle
245 # Use the "imp" module to protect the import from fixers.
247 _cProfile = imp.load_module('cProfile', *imp.find_module('cProfile'))
249 # The "cProfile" module has already been eliminated in favor of
250 # having "import profile" import the fast version when available.
254 sys.modules['profile'] = _cProfile
261 # Pre-2.3 Python has no platform module.
262 import_as('_scons_platform', 'platform')
268 # Before Python 3.0, the 'queue' module was named 'Queue'.
270 file, filename, suffix_mode_type = imp.find_module('Queue')
271 imp.load_module('queue', file, filename, suffix_mode_type)
277 except AttributeError:
278 # Pre-2.3 Python has no shlex.split() function.
280 # The full white-space splitting semantics of shlex.split() are
281 # complicated to reproduce by hand, so just use a compatibility
282 # version of the shlex module cribbed from Python 2.5 with some
283 # minor modifications for older Python versions.
285 import_as('_scons_shlex', 'shlex')
291 except AttributeError:
292 # Pre-2.3 Python has no shutil.move() function.
294 # Cribbed from Python 2.5.
298 """Recursively move a file or directory to another location.
300 If the destination is on our current filesystem, then simply use
301 rename. Otherwise, copy src to the dst and then remove src.
302 A lot more could be done here... A look at a mv.c shows a lot of
303 the issues this implementation glosses over.
309 if os.path.isdir(src):
310 if shutil.destinsrc(src, dst):
311 raise Error("Cannot move a directory '%s' into itself '%s'." % (src, dst))
312 shutil.copytree(src, dst, symlinks=True)
315 shutil.copy2(src,dst)
320 def destinsrc(src, dst):
321 src = os.path.abspath(src)
322 return os.path.abspath(dst)[:len(src)] == src
323 shutil.destinsrc = destinsrc
330 # Pre-2.4 Python has no subprocess module.
331 import_as('_scons_subprocess', 'subprocess')
336 except AttributeError:
337 # Pre-2.6 Python has no sys.intern() function.
340 sys.intern = builtins.intern
341 except AttributeError:
342 # Pre-2.x Python has no builtin intern() function.
349 except AttributeError:
350 # Pre-2.6 Python has no sys.maxsize attribute
351 # Wrapping sys in () is silly, but protects it from 2to3 renames fixer
352 sys.maxsize = (sys).maxint
358 except AttributeError:
359 # Pre-2.3 Python has no tempfile.mkstemp function, so try to simulate it.
360 # adapted from the mkstemp implementation in python 3.
363 def mkstemp(*args, **kw):
367 if 'text' in kw.keys() :
370 elif len( args ) == 4 :
373 flags = os.O_RDWR | os.O_CREAT | os.O_EXCL
374 if not text and hasattr( os, 'O_BINARY' ) :
375 flags = flags | os.O_BINARY
378 name = tempfile.mktemp(*args, **kw)
379 fd = os.open( name, flags, 0600 )
380 return (fd, os.path.abspath(name))
382 if e.errno == errno.EEXIST:
386 tempfile.mkstemp = mkstemp
392 # indent-tabs-mode:nil
394 # vim: set expandtab tabstop=4 shiftwidth=4: