mapnik/scons/scons-local-0.96.1/SCons/Node/FS.py
2006-01-31 23:09:52 +00:00

1867 lines
65 KiB
Python

"""scons.Node.FS
File system nodes.
These Nodes represent the canonical external objects that people think
of when they think of building software: files and directories.
This initializes a "default_fs" Node with an FS at the current directory
for its own purposes, and for use by scripts or modules looking for the
canonical default.
"""
#
# Copyright (c) 2001, 2002, 2003, 2004 The SCons Foundation
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#
__revision__ = "/home/scons/scons/branch.0/baseline/src/engine/SCons/Node/FS.py 0.96.1.D001 2004/08/23 09:55:29 knight"
import os
import os.path
import shutil
import stat
import string
import sys
import time
import cStringIO
import SCons.Action
from SCons.Debug import logInstanceCreation
import SCons.Errors
import SCons.Node
import SCons.Sig.MD5
import SCons.Util
import SCons.Warnings
#
# We stringify these file system Nodes a lot. Turning a file system Node
# into a string is non-trivial, because the final string representation
# can depend on a lot of factors: whether it's a derived target or not,
# whether it's linked to a repository or source directory, and whether
# there's duplication going on. The normal technique for optimizing
# calculations like this is to memoize (cache) the string value, so you
# only have to do the calculation once.
#
# A number of the above factors, however, can be set after we've already
# been asked to return a string for a Node, because a Repository() or
# BuildDir() call or the like may not occur until later in SConscript
# files. So this variable controls whether we bother trying to save
# string values for Nodes. The wrapper interface can set this whenever
# they're done mucking with Repository and BuildDir and the other stuff,
# to let this module know it can start returning saved string values
# for Nodes.
#
Save_Strings = None
def save_strings(val):
global Save_Strings
Save_Strings = val
#
# SCons.Action objects for interacting with the outside world.
#
# The Node.FS methods in this module should use these actions to
# create and/or remove files and directories; they should *not* use
# os.{link,symlink,unlink,mkdir}(), etc., directly.
#
# Using these SCons.Action objects ensures that descriptions of these
# external activities are properly displayed, that the displays are
# suppressed when the -s (silent) option is used, and (most importantly)
# the actions are disabled when the the -n option is used, in which case
# there should be *no* changes to the external file system(s)...
#
def _copy_func(src, dest):
shutil.copy2(src, dest)
st=os.stat(src)
os.chmod(dest, stat.S_IMODE(st[stat.ST_MODE]) | stat.S_IWRITE)
Valid_Duplicates = ['hard-soft-copy', 'soft-hard-copy',
'hard-copy', 'soft-copy', 'copy']
Link_Funcs = [] # contains the callables of the specified duplication style
def set_duplicate(duplicate):
# Fill in the Link_Funcs list according to the argument
# (discarding those not available on the platform).
# Set up the dictionary that maps the argument names to the
# underlying implementations. We do this inside this function,
# not in the top-level module code, so that we can remap os.link
# and os.symlink for testing purposes.
try:
_hardlink_func = os.link
except AttributeError:
_hardlink_func = None
try:
_softlink_func = os.symlink
except AttributeError:
_softlink_func = None
link_dict = {
'hard' : _hardlink_func,
'soft' : _softlink_func,
'copy' : _copy_func
}
if not duplicate in Valid_Duplicates:
raise SCons.Errors.InternalError, ("The argument of set_duplicate "
"should be in Valid_Duplicates")
global Link_Funcs
Link_Funcs = []
for func in string.split(duplicate,'-'):
if link_dict[func]:
Link_Funcs.append(link_dict[func])
def LinkFunc(target, source, env):
# Relative paths cause problems with symbolic links, so
# we use absolute paths, which may be a problem for people
# who want to move their soft-linked src-trees around. Those
# people should use the 'hard-copy' mode, softlinks cannot be
# used for that; at least I have no idea how ...
src = source[0].abspath
dest = target[0].abspath
dir, file = os.path.split(dest)
if dir and not os.path.isdir(dir):
os.makedirs(dir)
if not Link_Funcs:
# Set a default order of link functions.
set_duplicate('hard-soft-copy')
# Now link the files with the previously specified order.
for func in Link_Funcs:
try:
func(src,dest)
break
except OSError:
if func == Link_Funcs[-1]:
# exception of the last link method (copy) are fatal
raise
else:
pass
return 0
Link = SCons.Action.Action(LinkFunc, None)
def LocalString(target, source, env):
return 'Local copy of %s from %s' % (target[0], source[0])
LocalCopy = SCons.Action.Action(LinkFunc, LocalString)
def UnlinkFunc(target, source, env):
t = target[0]
t.fs.unlink(t.abspath)
return 0
Unlink = SCons.Action.Action(UnlinkFunc, None)
def MkdirFunc(target, source, env):
t = target[0]
p = t.abspath
if not t.fs.exists(p):
t.fs.mkdir(p)
return 0
Mkdir = SCons.Action.Action(MkdirFunc, None, presub=None)
MkdirBuilder = None
def get_MkdirBuilder():
global MkdirBuilder
if MkdirBuilder is None:
import SCons.Builder
# "env" will get filled in by Executor.get_build_env()
# calling SCons.Defaults.DefaultEnvironment() when necessary.
MkdirBuilder = SCons.Builder.Builder(action = Mkdir,
env = None,
explain = None)
return MkdirBuilder
def CacheRetrieveFunc(target, source, env):
t = target[0]
fs = t.fs
cachedir, cachefile = t.cachepath()
if fs.exists(cachefile):
fs.copy2(cachefile, t.path)
st = fs.stat(cachefile)
fs.chmod(t.path, stat.S_IMODE(st[stat.ST_MODE]) | stat.S_IWRITE)
return 0
return 1
def CacheRetrieveString(target, source, env):
t = target[0]
cachedir, cachefile = t.cachepath()
if t.fs.exists(cachefile):
return "Retrieved `%s' from cache" % t.path
return None
CacheRetrieve = SCons.Action.Action(CacheRetrieveFunc, CacheRetrieveString)
CacheRetrieveSilent = SCons.Action.Action(CacheRetrieveFunc, None)
def CachePushFunc(target, source, env):
t = target[0]
fs = t.fs
cachedir, cachefile = t.cachepath()
if fs.exists(cachefile):
# Don't bother copying it if it's already there.
return
if not fs.isdir(cachedir):
fs.makedirs(cachedir)
tempfile = cachefile+'.tmp'
try:
fs.copy2(t.path, tempfile)
fs.rename(tempfile, cachefile)
st = fs.stat(t.path)
fs.chmod(cachefile, stat.S_IMODE(st[stat.ST_MODE]) | stat.S_IWRITE)
except OSError:
# It's possible someone else tried writing the file at the same
# time we did. Print a warning but don't stop the build, since
# it doesn't affect the correctness of the build.
SCons.Warnings.warn(SCons.Warnings.CacheWriteErrorWarning,
"Unable to copy %s to cache. Cache file is %s"
% (str(target), cachefile))
return
CachePush = SCons.Action.Action(CachePushFunc, None)
class _Null:
pass
_null = _Null()
DefaultSCCSBuilder = None
DefaultRCSBuilder = None
def get_DefaultSCCSBuilder():
global DefaultSCCSBuilder
if DefaultSCCSBuilder is None:
import SCons.Builder
# "env" will get filled in by Executor.get_build_env()
# calling SCons.Defaults.DefaultEnvironment() when necessary.
DefaultSCCSBuilder = SCons.Builder.Builder(action = '$SCCSCOM',
env = None)
return DefaultSCCSBuilder
def get_DefaultRCSBuilder():
global DefaultRCSBuilder
if DefaultRCSBuilder is None:
import SCons.Builder
# "env" will get filled in by Executor.get_build_env()
# calling SCons.Defaults.DefaultEnvironment() when necessary.
DefaultRCSBuilder = SCons.Builder.Builder(action = '$RCS_COCOM',
env = None)
return DefaultRCSBuilder
#
class ParentOfRoot:
"""
An instance of this class is used as the parent of the root of a
filesystem (POSIX) or drive (Win32). This isn't actually a node,
but it looks enough like one so that we don't have to have
special purpose code everywhere to deal with dir being None.
This class is an instance of the Null object pattern.
"""
def __init__(self):
self.abspath = ''
self.path = ''
self.name=''
self.duplicate=0
self.srcdir=None
self.build_dirs=[]
def is_under(self, dir):
return 0
def up(self):
return None
def getRepositories(self):
return []
def get_dir(self):
return None
def src_builder(self):
return _null
def entry_abspath(self, name):
return name
def entry_path(self, name):
return name
# Cygwin's os.path.normcase pretends it's on a case-sensitive filesystem.
_is_cygwin = sys.platform == "cygwin"
if os.path.normcase("TeSt") == os.path.normpath("TeSt") and not _is_cygwin:
def _my_normcase(x):
return x
else:
def _my_normcase(x):
return string.upper(x)
class EntryProxy(SCons.Util.Proxy):
def __get_abspath(self):
entry = self.get()
return SCons.Util.SpecialAttrWrapper(entry.get_abspath(),
entry.name + "_abspath")
def __get_filebase(self):
name = self.get().name
return SCons.Util.SpecialAttrWrapper(SCons.Util.splitext(name)[0],
name + "_filebase")
def __get_suffix(self):
name = self.get().name
return SCons.Util.SpecialAttrWrapper(SCons.Util.splitext(name)[1],
name + "_suffix")
def __get_file(self):
name = self.get().name
return SCons.Util.SpecialAttrWrapper(name, name + "_file")
def __get_base_path(self):
"""Return the file's directory and file name, with the
suffix stripped."""
entry = self.get()
return SCons.Util.SpecialAttrWrapper(SCons.Util.splitext(entry.get_path())[0],
entry.name + "_base")
def __get_posix_path(self):
"""Return the path with / as the path separator,
regardless of platform."""
if os.sep == '/':
return self
else:
entry = self.get()
r = string.replace(entry.get_path(), os.sep, '/')
return SCons.Util.SpecialAttrWrapper(r, entry.name + "_posix")
def __get_win32_path(self):
"""Return the path with \ as the path separator,
regardless of platform."""
if os.sep == '\\':
return self
else:
entry = self.get()
r = string.replace(entry.get_path(), os.sep, '\\')
return SCons.Util.SpecialAttrWrapper(r, entry.name + "_win32")
def __get_srcnode(self):
return EntryProxy(self.get().srcnode())
def __get_srcdir(self):
"""Returns the directory containing the source node linked to this
node via BuildDir(), or the directory of this node if not linked."""
return EntryProxy(self.get().srcnode().dir)
def __get_rsrcnode(self):
return EntryProxy(self.get().srcnode().rfile())
def __get_rsrcdir(self):
"""Returns the directory containing the source node linked to this
node via BuildDir(), or the directory of this node if not linked."""
return EntryProxy(self.get().srcnode().rfile().dir)
def __get_dir(self):
return EntryProxy(self.get().dir)
dictSpecialAttrs = { "base" : __get_base_path,
"posix" : __get_posix_path,
"win32" : __get_win32_path,
"srcpath" : __get_srcnode,
"srcdir" : __get_srcdir,
"dir" : __get_dir,
"abspath" : __get_abspath,
"filebase" : __get_filebase,
"suffix" : __get_suffix,
"file" : __get_file,
"rsrcpath" : __get_rsrcnode,
"rsrcdir" : __get_rsrcdir,
}
def __getattr__(self, name):
# This is how we implement the "special" attributes
# such as base, posix, srcdir, etc.
try:
return self.dictSpecialAttrs[name](self)
except KeyError:
try:
attr = SCons.Util.Proxy.__getattr__(self, name)
except AttributeError:
entry = self.get()
classname = string.split(str(entry.__class__), '.')[-1]
raise AttributeError, "%s instance '%s' has no attribute '%s'" % (classname, entry.name, name)
return attr
class Base(SCons.Node.Node):
"""A generic class for file system entries. This class is for
when we don't know yet whether the entry being looked up is a file
or a directory. Instances of this class can morph into either
Dir or File objects by a later, more precise lookup.
Note: this class does not define __cmp__ and __hash__ for
efficiency reasons. SCons does a lot of comparing of
Node.FS.{Base,Entry,File,Dir} objects, so those operations must be
as fast as possible, which means we want to use Python's built-in
object identity comparisons.
"""
def __init__(self, name, directory, fs):
"""Initialize a generic Node.FS.Base object.
Call the superclass initialization, take care of setting up
our relative and absolute paths, identify our parent
directory, and indicate that this node should use
signatures."""
if __debug__: logInstanceCreation(self, 'Node.FS.Base')
SCons.Node.Node.__init__(self)
self.name = name
self.fs = fs
self.relpath = {self : '.'}
assert directory, "A directory must be provided"
self.abspath = directory.entry_abspath(name)
if directory.path == '.':
self.path = name
else:
self.path = directory.entry_path(name)
self.dir = directory
self.cwd = None # will hold the SConscript directory for target nodes
self.duplicate = directory.duplicate
def clear(self):
"""Completely clear a Node.FS.Base object of all its cached
state (so that it can be re-evaluated by interfaces that do
continuous integration builds).
"""
SCons.Node.Node.clear(self)
try:
delattr(self, '_exists')
except AttributeError:
pass
try:
delattr(self, '_rexists')
except AttributeError:
pass
try:
delattr(self, '_str_val')
except AttributeError:
pass
self.relpath = {self : '.'}
def get_dir(self):
return self.dir
def get_suffix(self):
return SCons.Util.splitext(self.name)[1]
def rfile(self):
return self
def __str__(self):
"""A Node.FS.Base object's string representation is its path
name."""
try:
return self._str_val
except AttributeError:
global Save_Strings
if self.duplicate or self.is_derived():
str_val = self.get_path()
else:
str_val = self.srcnode().get_path()
if Save_Strings:
self._str_val = str_val
return str_val
rstr = __str__
def exists(self):
try:
return self._exists
except AttributeError:
self._exists = self.fs.exists(self.abspath)
return self._exists
def rexists(self):
try:
return self._rexists
except AttributeError:
self._rexists = self.rfile().exists()
return self._rexists
def is_under(self, dir):
if self is dir:
return 1
else:
return self.dir.is_under(dir)
def set_local(self):
self._local = 1
def srcnode(self):
"""If this node is in a build path, return the node
corresponding to its source file. Otherwise, return
ourself."""
try:
return self._srcnode
except AttributeError:
dir=self.dir
name=self.name
while dir:
if dir.srcdir:
self._srcnode = self.fs.Entry(name, dir.srcdir,
klass=self.__class__)
return self._srcnode
name = dir.name + os.sep + name
dir=dir.get_dir()
self._srcnode = self
return self._srcnode
def get_path(self, dir=None):
"""Return path relative to the current working directory of the
Node.FS.Base object that owns us."""
if not dir:
dir = self.fs.getcwd()
try:
return self.relpath[dir]
except KeyError:
path_elems = []
d = self
while d != dir and not isinstance(d, ParentOfRoot):
path_elems.append(d.name)
d = d.dir
path_elems.reverse()
ret = string.join(path_elems, os.sep)
self.relpath[dir] = ret
return ret
def set_src_builder(self, builder):
"""Set the source code builder for this node."""
self.sbuilder = builder
if not self.has_builder():
self.builder_set(builder)
def src_builder(self):
"""Fetch the source code builder for this node.
If there isn't one, we cache the source code builder specified
for the directory (which in turn will cache the value from its
parent directory, and so on up to the file system root).
"""
try:
scb = self.sbuilder
except AttributeError:
scb = self.dir.src_builder()
self.sbuilder = scb
return scb
def get_abspath(self):
"""Get the absolute path of the file."""
return self.abspath
def for_signature(self):
# Return just our name. Even an absolute path would not work,
# because that can change thanks to symlinks or remapped network
# paths.
return self.name
def get_subst_proxy(self):
try:
return self._proxy
except AttributeError:
ret = EntryProxy(self)
self._proxy = ret
return ret
class Entry(Base):
"""This is the class for generic Node.FS entries--that is, things
that could be a File or a Dir, but we're just not sure yet.
Consequently, the methods in this class really exist just to
transform their associated object into the right class when the
time comes, and then call the same-named method in the transformed
class."""
def rfile(self):
"""We're a generic Entry, but the caller is actually looking for
a File at this point, so morph into one."""
self.__class__ = File
self._morph()
self.clear()
return File.rfile(self)
def get_found_includes(self, env, scanner, target):
"""If we're looking for included files, it's because this Entry
is really supposed to be a File itself."""
node = self.rfile()
return node.get_found_includes(env, scanner, target)
def scanner_key(self):
return self.get_suffix()
def get_contents(self):
"""Fetch the contents of the entry.
Since this should return the real contents from the file
system, we check to see into what sort of subclass we should
morph this Entry."""
if self.fs.isfile(self.abspath):
self.__class__ = File
self._morph()
return File.get_contents(self)
if self.fs.isdir(self.abspath):
self.__class__ = Dir
self._morph()
return Dir.get_contents(self)
if self.fs.islink(self.abspath):
return '' # avoid errors for dangling symlinks
raise AttributeError
def exists(self):
"""Return if the Entry exists. Check the file system to see
what we should turn into first. Assume a file if there's no
directory."""
if self.fs.isdir(self.abspath):
self.__class__ = Dir
self._morph()
return Dir.exists(self)
else:
self.__class__ = File
self._morph()
self.clear()
return File.exists(self)
def calc_signature(self, calc=None):
"""Return the Entry's calculated signature. Check the file
system to see what we should turn into first. Assume a file if
there's no directory."""
if self.fs.isdir(self.abspath):
self.__class__ = Dir
self._morph()
return Dir.calc_signature(self, calc)
else:
self.__class__ = File
self._morph()
self.clear()
return File.calc_signature(self, calc)
def must_be_a_Dir(self):
"""Called to make sure a Node is a Dir. Since we're an
Entry, we can morph into one."""
self.__class__ = Dir
self._morph()
# This is for later so we can differentiate between Entry the class and Entry
# the method of the FS class.
_classEntry = Entry
class LocalFS:
# This class implements an abstraction layer for operations involving
# a local file system. Essentially, this wraps any function in
# the os, os.path or shutil modules that we use to actually go do
# anything with or to the local file system.
#
# Note that there's a very good chance we'll refactor this part of
# the architecture in some way as we really implement the interface(s)
# for remote file system Nodes. For example, the right architecture
# might be to have this be a subclass instead of a base class.
# Nevertheless, we're using this as a first step in that direction.
#
# We're not using chdir() yet because the calling subclass method
# needs to use os.chdir() directly to avoid recursion. Will we
# really need this one?
#def chdir(self, path):
# return os.chdir(path)
def chmod(self, path, mode):
return os.chmod(path, mode)
def copy2(self, src, dst):
return shutil.copy2(src, dst)
def exists(self, path):
return os.path.exists(path)
def getmtime(self, path):
return os.path.getmtime(path)
def isdir(self, path):
return os.path.isdir(path)
def isfile(self, path):
return os.path.isfile(path)
def link(self, src, dst):
return os.link(src, dst)
def listdir(self, path):
return os.listdir(path)
def makedirs(self, path):
return os.makedirs(path)
def mkdir(self, path):
return os.mkdir(path)
def rename(self, old, new):
return os.rename(old, new)
def stat(self, path):
return os.stat(path)
def symlink(self, src, dst):
return os.symlink(src, dst)
def open(self, path):
return open(path)
def unlink(self, path):
return os.unlink(path)
if hasattr(os, 'symlink'):
def islink(self, path):
return os.path.islink(path)
def exists_or_islink(self, path):
return os.path.exists(path) or os.path.islink(path)
else:
def islink(self, path):
return 0 # no symlinks
exists_or_islink = exists
#class RemoteFS:
# # Skeleton for the obvious methods we might need from the
# # abstraction layer for a remote filesystem.
# def upload(self, local_src, remote_dst):
# pass
# def download(self, remote_src, local_dst):
# pass
class FS(LocalFS):
def __init__(self, path = None):
"""Initialize the Node.FS subsystem.
The supplied path is the top of the source tree, where we
expect to find the top-level build file. If no path is
supplied, the current directory is the default.
The path argument must be a valid absolute path.
"""
if __debug__: logInstanceCreation(self)
self.Top = None
if path == None:
self.pathTop = os.getcwd()
else:
self.pathTop = path
self.Root = {}
self.SConstruct_dir = None
self.CachePath = None
self.cache_force = None
self.cache_show = None
def set_toplevel_dir(self, path):
assert not self.Top, "You can only set the top-level path on an FS object that has not had its File, Dir, or Entry methods called yet."
self.pathTop = path
def set_SConstruct_dir(self, dir):
self.SConstruct_dir = dir
def __setTopLevelDir(self):
if not self.Top:
self.Top = self.__doLookup(Dir, os.path.normpath(self.pathTop))
self.Top.path = '.'
self._cwd = self.Top
def getcwd(self):
self.__setTopLevelDir()
return self._cwd
def __checkClass(self, node, klass):
if isinstance(node, klass) or klass == Entry:
return node
if node.__class__ == Entry:
node.__class__ = klass
node._morph()
return node
raise TypeError, "Tried to lookup %s '%s' as a %s." % \
(node.__class__.__name__, node.path, klass.__name__)
def __doLookup(self, fsclass, name, directory = None, create = 1):
"""This method differs from the File and Dir factory methods in
one important way: the meaning of the directory parameter.
In this method, if directory is None or not supplied, the supplied
name is expected to be an absolute path. If you try to look up a
relative path with directory=None, then an AssertionError will be
raised."""
if not name:
# This is a stupid hack to compensate for the fact
# that the POSIX and Win32 versions of os.path.normpath()
# behave differently. In particular, in POSIX:
# os.path.normpath('./') == '.'
# in Win32
# os.path.normpath('./') == ''
# os.path.normpath('.\\') == ''
#
# This is a definite bug in the Python library, but we have
# to live with it.
name = '.'
path_comp = string.split(name, os.sep)
drive, path_first = os.path.splitdrive(path_comp[0])
if not path_first:
# Absolute path
drive = _my_normcase(drive)
try:
directory = self.Root[drive]
except KeyError:
if not create:
raise SCons.Errors.UserError
directory = RootDir(drive, ParentOfRoot(), self)
self.Root[drive] = directory
path_comp = path_comp[1:]
else:
path_comp = [ path_first, ] + path_comp[1:]
if not path_comp:
path_comp = ['']
# Lookup the directory
for path_name in path_comp[:-1]:
path_norm = _my_normcase(path_name)
try:
d = directory.entries[path_norm]
except KeyError:
if not create:
raise SCons.Errors.UserError
# look at the actual filesystem and make sure there isn't
# a file already there
path = directory.entry_path(path_name)
if self.isfile(path):
raise TypeError, \
"File %s found where directory expected." % path
dir_temp = Dir(path_name, directory, self)
directory.entries[path_norm] = dir_temp
directory.add_wkid(dir_temp)
directory = dir_temp
else:
d.must_be_a_Dir()
directory = d
entry_norm = _my_normcase(path_comp[-1])
try:
e = directory.entries[entry_norm]
except KeyError:
if not create:
raise SCons.Errors.UserError
# make sure we don't create File nodes when there is actually
# a directory at that path on the disk, and vice versa
path = directory.entry_path(path_comp[-1])
if fsclass == File:
if self.isdir(path):
raise TypeError, \
"Directory %s found where file expected." % path
elif fsclass == Dir:
if self.isfile(path):
raise TypeError, \
"File %s found where directory expected." % path
result = fsclass(path_comp[-1], directory, self)
directory.entries[entry_norm] = result
directory.add_wkid(result)
else:
result = self.__checkClass(e, fsclass)
return result
def __transformPath(self, name, directory):
"""Take care of setting up the correct top-level directory,
usually in preparation for a call to doLookup().
If the path name is prepended with a '#', then it is unconditionally
interpreted as relative to the top-level directory of this FS.
If directory is None, and name is a relative path,
then the same applies.
"""
self.__setTopLevelDir()
if name and name[0] == '#':
directory = self.Top
name = name[1:]
if name and (name[0] == os.sep or name[0] == '/'):
# Correct such that '#/foo' is equivalent
# to '#foo'.
name = name[1:]
name = os.path.join('.', os.path.normpath(name))
elif not directory:
directory = self._cwd
return (os.path.normpath(name), directory)
def chdir(self, dir, change_os_dir=0):
"""Change the current working directory for lookups.
If change_os_dir is true, we will also change the "real" cwd
to match.
"""
self.__setTopLevelDir()
curr=self._cwd
try:
if not dir is None:
self._cwd = dir
if change_os_dir:
os.chdir(dir.abspath)
except OSError:
self._cwd = curr
raise
def Entry(self, name, directory = None, create = 1, klass=None):
"""Lookup or create a generic Entry node with the specified name.
If the name is a relative path (begins with ./, ../, or a file
name), then it is looked up relative to the supplied directory
node, or to the top level directory of the FS (supplied at
construction time) if no directory is supplied.
"""
if not klass:
klass = Entry
if isinstance(name, Base):
return self.__checkClass(name, klass)
else:
if directory and not isinstance(directory, Dir):
directory = self.Dir(directory)
name, directory = self.__transformPath(name, directory)
return self.__doLookup(klass, name, directory, create)
def File(self, name, directory = None, create = 1):
"""Lookup or create a File node with the specified name. If
the name is a relative path (begins with ./, ../, or a file name),
then it is looked up relative to the supplied directory node,
or to the top level directory of the FS (supplied at construction
time) if no directory is supplied.
This method will raise TypeError if a directory is found at the
specified path.
"""
return self.Entry(name, directory, create, File)
def Dir(self, name, directory = None, create = 1):
"""Lookup or create a Dir node with the specified name. If
the name is a relative path (begins with ./, ../, or a file name),
then it is looked up relative to the supplied directory node,
or to the top level directory of the FS (supplied at construction
time) if no directory is supplied.
This method will raise TypeError if a normal file is found at the
specified path.
"""
return self.Entry(name, directory, create, Dir)
def BuildDir(self, build_dir, src_dir, duplicate=1):
"""Link the supplied build directory to the source directory
for purposes of building files."""
self.__setTopLevelDir()
if not isinstance(src_dir, SCons.Node.Node):
src_dir = self.Dir(src_dir)
if not isinstance(build_dir, SCons.Node.Node):
build_dir = self.Dir(build_dir)
if not src_dir.is_under(self.Top):
raise SCons.Errors.UserError, "Source directory must be under top of build tree."
if src_dir.is_under(build_dir):
raise SCons.Errors.UserError, "Source directory cannot be under build directory."
if build_dir.srcdir:
if build_dir.srcdir == src_dir:
return # We already did this.
raise SCons.Errors.UserError, "'%s' already has a source directory: '%s'."%(build_dir, build_dir.srcdir)
build_dir.link(src_dir, duplicate)
def Repository(self, *dirs):
"""Specify Repository directories to search."""
for d in dirs:
if not isinstance(d, SCons.Node.Node):
d = self.Dir(d)
self.__setTopLevelDir()
self.Top.addRepository(d)
def Rsearch(self, path, clazz=_classEntry, cwd=None):
"""Search for something in a Repository. Returns the first
one found in the list, or None if there isn't one."""
if isinstance(path, SCons.Node.Node):
return path
else:
name, d = self.__transformPath(path, cwd)
n = self.__doLookup(clazz, name, d)
if n.exists():
return n
if isinstance(n, Dir):
# If n is a Directory that has Repositories directly
# attached to it, then any of those is a valid Repository
# path. Return the first one that exists.
reps = filter(lambda x: x.exists(), n.getRepositories())
if len(reps):
return reps[0]
d = n.get_dir()
name = n.name
# Search repositories of all directories that this file is under.
while d:
for rep in d.getRepositories():
try:
rnode = self.__doLookup(clazz, name, rep)
# Only find the node if it exists and it is not
# a derived file. If for some reason, we are
# explicitly building a file IN a Repository, we
# don't want it to show up in the build tree.
# This is usually the case with BuildDir().
# We only want to find pre-existing files.
if rnode.exists() and \
(isinstance(rnode, Dir) or not rnode.is_derived()):
return rnode
except TypeError:
pass # Wrong type of node.
# Prepend directory name
name = d.name + os.sep + name
# Go up one directory
d = d.get_dir()
return None
def Rsearchall(self, pathlist, must_exist=1, clazz=_classEntry, cwd=None):
"""Search for a list of somethings in the Repository list."""
ret = []
if SCons.Util.is_String(pathlist):
pathlist = string.split(pathlist, os.pathsep)
if not SCons.Util.is_List(pathlist):
pathlist = [pathlist]
for path in filter(None, pathlist):
if isinstance(path, SCons.Node.Node):
ret.append(path)
else:
name, d = self.__transformPath(path, cwd)
n = self.__doLookup(clazz, name, d)
if not must_exist or n.exists():
ret.append(n)
if isinstance(n, Dir):
# If this node is a directory, then any repositories
# attached to this node can be repository paths.
ret.extend(filter(lambda x, me=must_exist, clazz=clazz: isinstance(x, clazz) and (not me or x.exists()),
n.getRepositories()))
d = n.get_dir()
name = n.name
# Search repositories of all directories that this file
# is under.
while d:
for rep in d.getRepositories():
try:
rnode = self.__doLookup(clazz, name, rep)
# Only find the node if it exists (or
# must_exist is zero) and it is not a
# derived file. If for some reason, we
# are explicitly building a file IN a
# Repository, we don't want it to show up in
# the build tree. This is usually the case
# with BuildDir(). We only want to find
# pre-existing files.
if (not must_exist or rnode.exists()) and \
(not rnode.is_derived() or isinstance(rnode, Dir)):
ret.append(rnode)
except TypeError:
pass # Wrong type of node.
# Prepend directory name
name = d.name + os.sep + name
# Go up one directory
d = d.get_dir()
return ret
def CacheDir(self, path):
self.CachePath = path
def build_dir_target_climb(self, dir, tail):
"""Create targets in corresponding build directories
Climb the directory tree, and look up path names
relative to any linked build directories we find.
"""
targets = []
message = None
while dir:
for bd in dir.build_dirs:
p = apply(os.path.join, [bd.path] + tail)
targets.append(self.Entry(p))
tail = [dir.name] + tail
dir = dir.up()
if targets:
message = "building associated BuildDir targets: %s" % string.join(map(str, targets))
return targets, message
class DummyExecutor:
"""Dummy executor class returned by Dir nodes to bamboozle SCons
into thinking we are an actual derived node, where our sources are
our directory entries."""
def cleanup(self):
pass
def get_raw_contents(self):
return ''
def get_contents(self):
return ''
def get_timestamp(self):
return 0
def get_build_env(self):
return None
class Dir(Base):
"""A class for directories in a file system.
"""
def __init__(self, name, directory, fs):
if __debug__: logInstanceCreation(self, 'Node.FS.Dir')
Base.__init__(self, name, directory, fs)
self._morph()
def _morph(self):
"""Turn a file system Node (either a freshly initialized directory
object or a separate Entry object) into a proper directory object.
Set up this directory's entries and hook it into the file
system tree. Specify that directories (this Node) don't use
signatures for calculating whether they're current."""
self.repositories = []
self.srcdir = None
self.entries = {}
self.entries['.'] = self
self.entries['..'] = self.dir
self.cwd = self
self.builder = get_MkdirBuilder()
self.searched = 0
self._sconsign = None
self.build_dirs = []
def __clearRepositoryCache(self, duplicate=None):
"""Called when we change the repository(ies) for a directory.
This clears any cached information that is invalidated by changing
the repository."""
for node in self.entries.values():
if node != self.dir:
if node != self and isinstance(node, Dir):
node.__clearRepositoryCache(duplicate)
else:
try:
del node._srcreps
except AttributeError:
pass
try:
del node._rfile
except AttributeError:
pass
try:
del node._rexists
except AttributeError:
pass
try:
del node._exists
except AttributeError:
pass
try:
del node._srcnode
except AttributeError:
pass
try:
del node._str_val
except AttributeError:
pass
if duplicate != None:
node.duplicate=duplicate
def __resetDuplicate(self, node):
if node != self:
node.duplicate = node.get_dir().duplicate
def Entry(self, name):
"""Create an entry node named 'name' relative to this directory."""
return self.fs.Entry(name, self)
def Dir(self, name):
"""Create a directory node named 'name' relative to this directory."""
return self.fs.Dir(name, self)
def File(self, name):
"""Create a file node named 'name' relative to this directory."""
return self.fs.File(name, self)
def link(self, srcdir, duplicate):
"""Set this directory as the build directory for the
supplied source directory."""
self.srcdir = srcdir
self.duplicate = duplicate
self.__clearRepositoryCache(duplicate)
srcdir.build_dirs.append(self)
def getRepositories(self):
"""Returns a list of repositories for this directory."""
if self.srcdir and not self.duplicate:
try:
return self._srcreps
except AttributeError:
self._srcreps = self.fs.Rsearchall(self.srcdir.path,
clazz=Dir,
must_exist=0,
cwd=self.fs.Top) \
+ self.repositories
return self._srcreps
return self.repositories
def addRepository(self, dir):
if not dir in self.repositories and dir != self:
self.repositories.append(dir)
self.__clearRepositoryCache()
def up(self):
return self.entries['..']
def root(self):
if not self.entries['..']:
return self
else:
return self.entries['..'].root()
def scan(self):
if not self.implicit is None:
return
self.implicit = []
self.implicit_dict = {}
self._children_reset()
try:
for filename in self.fs.listdir(self.abspath):
if filename != '.sconsign':
self.Entry(filename)
except OSError:
# Directory does not exist. No big deal
pass
keys = filter(lambda k: k != '.' and k != '..', self.entries.keys())
kids = map(lambda x, s=self: s.entries[x], keys)
def c(one, two):
return cmp(one.abspath, two.abspath)
kids.sort(c)
self._add_child(self.implicit, self.implicit_dict, kids)
def get_actions(self):
"""A null "builder" for directories."""
return []
def build(self, **kw):
"""A null "builder" for directories."""
global MkdirBuilder
if not self.builder is MkdirBuilder:
apply(SCons.Node.Node.build, [self,], kw)
def multiple_side_effect_has_builder(self):
global MkdirBuilder
return not self.builder is MkdirBuilder and self.has_builder()
def alter_targets(self):
"""Return any corresponding targets in a build directory.
"""
return self.fs.build_dir_target_climb(self, [])
def scanner_key(self):
"""A directory does not get scanned."""
return None
def get_contents(self):
"""Return aggregate contents of all our children."""
contents = cStringIO.StringIO()
for kid in self.children():
contents.write(kid.get_contents())
return contents.getvalue()
def prepare(self):
pass
def current(self, calc=None):
"""If all of our children were up-to-date, then this
directory was up-to-date, too."""
if not self.builder is MkdirBuilder and not self.exists():
return 0
state = 0
for kid in self.children():
s = kid.get_state()
if s and (not state or s > state):
state = s
import SCons.Node
if state == 0 or state == SCons.Node.up_to_date:
return 1
else:
return 0
def rdir(self):
try:
return self._rdir
except AttributeError:
self._rdir = self
if not self.exists():
n = self.fs.Rsearch(self.path, clazz=Dir, cwd=self.fs.Top)
if n:
self._rdir = n
return self._rdir
def sconsign(self):
"""Return the .sconsign file info for this directory,
creating it first if necessary."""
if not self._sconsign:
import SCons.SConsign
self._sconsign = SCons.SConsign.ForDirectory(self)
return self._sconsign
def srcnode(self):
"""Dir has a special need for srcnode()...if we
have a srcdir attribute set, then that *is* our srcnode."""
if self.srcdir:
return self.srcdir
return Base.srcnode(self)
def get_timestamp(self):
"""Return the latest timestamp from among our children"""
stamp = 0
for kid in self.children():
if kid.get_timestamp() > stamp:
stamp = kid.get_timestamp()
return stamp
def entry_abspath(self, name):
return self.abspath + os.sep + name
def entry_path(self, name):
return self.path + os.sep + name
def must_be_a_Dir(self):
"""Called to make sure a Node is a Dir. Since we're already
one, this is a no-op for us."""
pass
class RootDir(Dir):
"""A class for the root directory of a file system.
This is the same as a Dir class, except that the path separator
('/' or '\\') is actually part of the name, so we don't need to
add a separator when creating the path names of entries within
this directory.
"""
def __init__(self, name, directory, fs):
if __debug__: logInstanceCreation(self, 'Node.FS.RootDir')
Base.__init__(self, name, directory, fs)
self.path = self.path + os.sep
self.abspath = self.abspath + os.sep
self._morph()
def entry_abspath(self, name):
return self.abspath + name
def entry_path(self, name):
return self.path + name
class BuildInfo:
bsig = None
def __cmp__(self, other):
try:
return cmp(self.bsig, other.bsig)
except AttributeError:
return 1
class File(Base):
"""A class for files in a file system.
"""
def __init__(self, name, directory, fs):
if __debug__: logInstanceCreation(self, 'Node.FS.File')
Base.__init__(self, name, directory, fs)
self._morph()
def Entry(self, name):
"""Create an entry node named 'name' relative to
the SConscript directory of this file."""
return self.fs.Entry(name, self.cwd)
def Dir(self, name):
"""Create a directory node named 'name' relative to
the SConscript directory of this file."""
return self.fs.Dir(name, self.cwd)
def File(self, name):
"""Create a file node named 'name' relative to
the SConscript directory of this file."""
return self.fs.File(name, self.cwd)
def RDirs(self, pathlist):
"""Search for a list of directories in the Repository list."""
return self.fs.Rsearchall(pathlist, clazz=Dir, must_exist=0,
cwd=self.cwd)
def generate_build_dict(self):
"""Return an appropriate dictionary of values for building
this File."""
return {'Dir' : self.Dir,
'File' : self.File,
'RDirs' : self.RDirs}
def _morph(self):
"""Turn a file system node into a File object."""
self.scanner_paths = {}
self.found_includes = {}
if not hasattr(self, '_local'):
self._local = 0
def root(self):
return self.dir.root()
def scanner_key(self):
return self.get_suffix()
def get_contents(self):
if not self.rexists():
return ''
return open(self.rfile().abspath, "rb").read()
def get_timestamp(self):
if self.rexists():
return self.fs.getmtime(self.rfile().abspath)
else:
return 0
def store_info(self, obj):
# Merge our build information into the already-stored entry.
# This accomodates "chained builds" where a file that's a target
# in one build (SConstruct file) is a source in a different build.
# See test/chained-build.py for the use case.
entry = self.get_stored_info()
for key, val in obj.__dict__.items():
entry.__dict__[key] = val
self.dir.sconsign().set_entry(self.name, entry)
def get_stored_info(self):
try:
stored = self.dir.sconsign().get_entry(self.name)
if isinstance(stored, BuildInfo):
return stored
# The stored build information isn't a BuildInfo object.
# This probably means it's an old SConsignEntry from SCons
# 0.95 or before. The relevant attribute names are the same,
# though, so just copy the attributes over to an object of
# the correct type.
binfo = BuildInfo()
for key, val in stored.__dict__.items():
setattr(binfo, key, val)
return binfo
except:
return BuildInfo()
def get_stored_implicit(self):
binfo = self.get_stored_info()
try:
return binfo.bimplicit
except AttributeError:
return None
def get_found_includes(self, env, scanner, target):
"""Return the included implicit dependencies in this file.
Cache results so we only scan the file once regardless of
how many times this information is requested."""
if not scanner:
return []
try:
path = target.scanner_paths[scanner]
except AttributeError:
# The target had no scanner_paths attribute, which means
# it's an Alias or some other node that's not actually a
# file. In that case, back off and use the path for this
# node itself.
try:
path = self.scanner_paths[scanner]
except KeyError:
path = scanner.path(env, self.cwd)
self.scanner_paths[scanner] = path
except KeyError:
path = scanner.path(env, target.cwd)
target.scanner_paths[scanner] = path
try:
includes = self.found_includes[path]
except KeyError:
includes = scanner(self, env, path)
self.found_includes[path] = includes
return includes
def _createDir(self):
# ensure that the directories for this node are
# created.
listDirs = []
parent=self.dir
while parent:
if parent.exists():
break
listDirs.append(parent)
p = parent.up()
if isinstance(p, ParentOfRoot):
raise SCons.Errors.StopError, parent.path
parent = p
listDirs.reverse()
for dirnode in listDirs:
try:
# Don't call dirnode.build(), call the base Node method
# directly because we definitely *must* create this
# directory. The dirnode.build() method will suppress
# the build if it's the default builder.
SCons.Node.Node.build(dirnode)
# The build() action may or may not have actually
# created the directory, depending on whether the -n
# option was used or not. Delete the _exists and
# _rexists attributes so they can be reevaluated.
try:
delattr(dirnode, '_exists')
except AttributeError:
pass
try:
delattr(dirnode, '_rexists')
except AttributeError:
pass
except OSError:
pass
def retrieve_from_cache(self):
"""Try to retrieve the node's content from a cache
This method is called from multiple threads in a parallel build,
so only do thread safe stuff here. Do thread unsafe stuff in
built().
Returns true iff the node was successfully retrieved.
"""
b = self.is_derived()
if not b and not self.has_src_builder():
return None
if b and self.fs.CachePath:
if self.fs.cache_show:
if CacheRetrieveSilent(self, [], None) == 0:
self.build(presub=0, execute=0)
return 1
elif CacheRetrieve(self, [], None) == 0:
return 1
return None
def built(self):
"""Called just after this node is sucessfully built."""
# Push this file out to cache before the superclass Node.built()
# method has a chance to clear the build signature, which it
# will do if this file has a source scanner.
if self.fs.CachePath and self.fs.exists(self.path):
CachePush(self, [], None)
SCons.Node.Node.built(self)
self.found_includes = {}
try:
delattr(self, '_exists')
except AttributeError:
pass
try:
delattr(self, '_rexists')
except AttributeError:
pass
def visited(self):
if self.fs.CachePath and self.fs.cache_force and self.fs.exists(self.path):
CachePush(self, None, None)
def has_src_builder(self):
"""Return whether this Node has a source builder or not.
If this Node doesn't have an explicit source code builder, this
is where we figure out, on the fly, if there's a transparent
source code builder for it.
Note that if we found a source builder, we also set the
self.builder attribute, so that all of the methods that actually
*build* this file don't have to do anything different.
"""
try:
scb = self.sbuilder
except AttributeError:
if self.rexists():
scb = None
else:
scb = self.dir.src_builder()
if scb is _null:
scb = None
dir = self.dir.path
sccspath = os.path.join('SCCS', 's.' + self.name)
if dir != '.':
sccspath = os.path.join(dir, sccspath)
if self.fs.exists(sccspath):
scb = get_DefaultSCCSBuilder()
else:
rcspath = os.path.join('RCS', self.name + ',v')
if dir != '.':
rcspath = os.path.join(dir, rcspath)
if os.path.exists(rcspath):
scb = get_DefaultRCSBuilder()
self.builder = scb
self.sbuilder = scb
return not scb is None
def alter_targets(self):
"""Return any corresponding targets in a build directory.
"""
if self.is_derived():
return [], None
return self.fs.build_dir_target_climb(self.dir, [self.name])
def is_pseudo_derived(self):
return self.has_src_builder()
def prepare(self):
"""Prepare for this file to be created."""
SCons.Node.Node.prepare(self)
if self.get_state() != SCons.Node.up_to_date:
if self.exists():
if self.is_derived() and not self.precious:
try:
Unlink(self, [], None)
except OSError, e:
raise SCons.Errors.BuildError(node = self,
errstr = e.strerror)
try:
delattr(self, '_exists')
except AttributeError:
pass
else:
try:
self._createDir()
except SCons.Errors.StopError, drive:
desc = "No drive `%s' for target `%s'." % (drive, self)
raise SCons.Errors.StopError, desc
def remove(self):
"""Remove this file."""
if self.fs.exists_or_islink(self.path):
self.fs.unlink(self.path)
return 1
return None
def exists(self):
# Duplicate from source path if we are set up to do this.
if self.duplicate and not self.is_derived() and not self.linked:
src=self.srcnode().rfile()
if src.exists() and src.abspath != self.abspath:
self._createDir()
try:
Unlink(self, None, None)
except OSError:
pass
try:
Link(self, src, None)
except IOError, e:
desc = "Cannot duplicate `%s' in `%s': %s." % (src, self.dir, e.strerror)
raise SCons.Errors.StopError, desc
self.linked = 1
# The Link() action may or may not have actually
# created the file, depending on whether the -n
# option was used or not. Delete the _exists and
# _rexists attributes so they can be reevaluated.
try:
delattr(self, '_exists')
except AttributeError:
pass
try:
delattr(self, '_rexists')
except AttributeError:
pass
return Base.exists(self)
def new_binfo(self):
return BuildInfo()
def del_cinfo(self):
try:
del self.binfo.csig
except AttributeError:
pass
try:
del self.binfo.timestamp
except AttributeError:
pass
def calc_csig(self, calc=None):
"""
Generate a node's content signature, the digested signature
of its content.
node - the node
cache - alternate node to use for the signature cache
returns - the content signature
"""
if calc is None:
calc = self.calculator()
try:
return self.binfo.csig
except AttributeError:
pass
if calc.max_drift >= 0:
old = self.get_stored_info()
else:
old = BuildInfo()
try:
mtime = self.get_timestamp()
except:
mtime = 0
raise SCons.Errors.UserError, "no such %s" % self
try:
if (old.timestamp and old.csig and old.timestamp == mtime):
# use the signature stored in the .sconsign file
csig = old.csig
else:
csig = calc.module.signature(self)
except AttributeError:
csig = calc.module.signature(self)
if calc.max_drift >= 0 and (time.time() - mtime) > calc.max_drift:
try:
binfo = self.binfo
except AttributeError:
binfo = self.binfo = self.new_binfo()
binfo.csig = csig
binfo.timestamp = mtime
self.store_info(binfo)
return csig
def current(self, calc=None, scan=1):
self.binfo = self.gen_binfo(calc)
if self.always_build:
return None
if not self.exists():
# The file doesn't exist locally...
r = self.rfile()
if r != self:
# ...but there is one in a Repository...
old = r.get_stored_info()
if old == self.binfo:
# ...and it's even up-to-date...
if self._local:
# ...and they'd like a local copy.
LocalCopy(self, r, None)
self.store_info(self.binfo)
return 1
self._rfile = self
return None
else:
old = self.get_stored_info()
return (old == self.binfo)
def rfile(self):
try:
return self._rfile
except AttributeError:
self._rfile = self
if not self.exists():
n = self.fs.Rsearch(self.path, clazz=File,
cwd=self.fs.Top)
if n:
self._rfile = n
return self._rfile
def rstr(self):
return str(self.rfile())
def cachepath(self):
if not self.fs.CachePath:
return None, None
if self.binfo.bsig is None:
raise SCons.Errors.InternalError, "cachepath(%s) found a bsig of None" % self.path
# Add the path to the cache signature, because multiple
# targets built by the same action will all have the same
# build signature, and we have to differentiate them somehow.
cache_sig = SCons.Sig.MD5.collect([self.binfo.bsig, self.path])
subdir = string.upper(cache_sig[0])
dir = os.path.join(self.fs.CachePath, subdir)
return dir, os.path.join(dir, cache_sig)
def target_from_source(self, prefix, suffix, splitext=SCons.Util.splitext):
return self.dir.File(prefix + splitext(self.name)[0] + suffix)
def must_be_a_Dir(self):
"""Called to make sure a Node is a Dir. Since we're already a
File, this is a TypeError..."""
raise TypeError, "Tried to lookup File '%s' as a Dir." % self.path
default_fs = FS()
def find_file(filename, paths, node_factory = default_fs.File):
"""
find_file(str, [Dir()]) -> [nodes]
filename - a filename to find
paths - a list of directory path *nodes* to search in
returns - the node created from the found file.
Find a node corresponding to either a derived file or a file
that exists already.
Only the first file found is returned, and none is returned
if no file is found.
"""
retval = None
for dir in paths:
try:
node = node_factory(filename, dir)
# Return true if the node exists or is a derived node.
if node.is_derived() or \
node.is_pseudo_derived() or \
(isinstance(node, SCons.Node.FS.Base) and node.exists()):
retval = node
break
except TypeError:
# If we find a directory instead of a file, we don't care
pass
return retval
def find_files(filenames, paths, node_factory = default_fs.File):
"""
find_files([str], [Dir()]) -> [nodes]
filenames - a list of filenames to find
paths - a list of directory path *nodes* to search in
returns - the nodes created from the found files.
Finds nodes corresponding to either derived files or files
that exist already.
Only the first file found is returned for each filename,
and any files that aren't found are ignored.
"""
nodes = map(lambda x, paths=paths, node_factory=node_factory:
find_file(x, paths, node_factory),
filenames)
return filter(lambda x: x != None, nodes)