mirror of https://github.com/python/cpython
117 lines
4.2 KiB
Python
117 lines
4.2 KiB
Python
"""distutils.dep_util
|
|
|
|
Utility functions for simple, timestamp-based dependency of files
|
|
and groups of files; also, function based entirely on such
|
|
timestamp dependency analysis."""
|
|
|
|
# created 2000/04/03, Greg Ward (extracted from util.py)
|
|
|
|
__revision__ = "$Id$"
|
|
|
|
import os
|
|
from distutils.errors import DistutilsFileError
|
|
|
|
|
|
def newer (source, target):
|
|
"""Return true if 'source' exists and is more recently modified than
|
|
'target', or if 'source' exists and 'target' doesn't. Return
|
|
false if both exist and 'target' is the same age or younger than
|
|
'source'. Raise DistutilsFileError if 'source' does not
|
|
exist."""
|
|
|
|
if not os.path.exists (source):
|
|
raise DistutilsFileError, "file '%s' does not exist" % source
|
|
if not os.path.exists (target):
|
|
return 1
|
|
|
|
from stat import ST_MTIME
|
|
mtime1 = os.stat(source)[ST_MTIME]
|
|
mtime2 = os.stat(target)[ST_MTIME]
|
|
|
|
return mtime1 > mtime2
|
|
|
|
# newer ()
|
|
|
|
|
|
def newer_pairwise (sources, targets):
|
|
"""Walk two filename lists in parallel, testing if each source is newer
|
|
than its corresponding target. Return a pair of lists (sources,
|
|
targets) where source is newer than target, according to the
|
|
semantics of 'newer()'."""
|
|
|
|
if len (sources) != len (targets):
|
|
raise ValueError, "'sources' and 'targets' must be same length"
|
|
|
|
# build a pair of lists (sources, targets) where source is newer
|
|
n_sources = []
|
|
n_targets = []
|
|
for i in range (len (sources)):
|
|
if newer (sources[i], targets[i]):
|
|
n_sources.append (sources[i])
|
|
n_targets.append (targets[i])
|
|
|
|
return (n_sources, n_targets)
|
|
|
|
# newer_pairwise ()
|
|
|
|
|
|
def newer_group (sources, target, missing='error'):
|
|
"""Return true if 'target' is out-of-date with respect to any
|
|
file listed in 'sources'. In other words, if 'target' exists and
|
|
is newer than every file in 'sources', return false; otherwise
|
|
return true. 'missing' controls what we do when a source file is
|
|
missing; the default ("error") is to blow up with an OSError from
|
|
inside 'stat()'; if it is "ignore", we silently drop any missing
|
|
source files; if it is "newer", any missing source files make us
|
|
assume that 'target' is out-of-date (this is handy in "dry-run"
|
|
mode: it'll make you pretend to carry out commands that wouldn't
|
|
work because inputs are missing, but that doesn't matter because
|
|
you're not actually going to run the commands)."""
|
|
|
|
# If the target doesn't even exist, then it's definitely out-of-date.
|
|
if not os.path.exists (target):
|
|
return 1
|
|
|
|
# Otherwise we have to find out the hard way: if *any* source file
|
|
# is more recent than 'target', then 'target' is out-of-date and
|
|
# we can immediately return true. If we fall through to the end
|
|
# of the loop, then 'target' is up-to-date and we return false.
|
|
from stat import ST_MTIME
|
|
target_mtime = os.stat (target)[ST_MTIME]
|
|
for source in sources:
|
|
if not os.path.exists (source):
|
|
if missing == 'error': # blow up when we stat() the file
|
|
pass
|
|
elif missing == 'ignore': # missing source dropped from
|
|
continue # target's dependency list
|
|
elif missing == 'newer': # missing source means target is
|
|
return 1 # out-of-date
|
|
|
|
source_mtime = os.stat(source)[ST_MTIME]
|
|
if source_mtime > target_mtime:
|
|
return 1
|
|
else:
|
|
return 0
|
|
|
|
# newer_group ()
|
|
|
|
|
|
# XXX this isn't used anywhere, and worse, it has the same name as a method
|
|
# in Command with subtly different semantics. (This one just has one
|
|
# source -> one dest; that one has many sources -> one dest.) Nuke it?
|
|
def make_file (src, dst, func, args,
|
|
verbose=0, update_message=None, noupdate_message=None):
|
|
"""Makes 'dst' from 'src' (both filenames) by calling 'func' with
|
|
'args', but only if it needs to: i.e. if 'dst' does not exist or
|
|
'src' is newer than 'dst'."""
|
|
|
|
if newer (src, dst):
|
|
if verbose and update_message:
|
|
print update_message
|
|
apply (func, args)
|
|
else:
|
|
if verbose and noupdate_message:
|
|
print noupdate_message
|
|
|
|
# make_file ()
|