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- """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: dep_util.py,v 1.1 2000/04/04 02:05:59 gward Exp $"
-
- 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- """Return true if 'target' is out-of-date with respect to any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- assume that 'target' is out-of-date (this is handy in "dry-run"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 ()
-