parent
631a152b8e
commit
090d9f7b00
2 changed files with 177 additions and 0 deletions
@ -0,0 +1,9 @@ |
||||
# $Id: __init__.py,v 1.1 2010-09-27 19:47:19 wirawan Exp $ |
||||
# |
||||
# wpylib.file module |
||||
# Created: 20100927 |
||||
# Wirawan Purwanto |
||||
|
||||
"""File-related stuff.""" |
||||
|
||||
pass |
@ -0,0 +1,168 @@ |
||||
#!/usr/bin/python |
||||
# $Id: file_utils.py,v 1.1 2010-09-27 19:47:19 wirawan Exp $ |
||||
# |
||||
# pyqmc.utils.file_utils module |
||||
# File-manipulation utilities |
||||
# |
||||
# Wirawan Purwanto |
||||
# Created: 20090601 |
||||
# |
||||
# Routines put here are commonly used in my own scripts. |
||||
# They are not necessarily suitable for general-purpose uses; evaluate |
||||
# your needs and see if they can them as well. |
||||
# |
||||
|
||||
import bz2 |
||||
import glob |
||||
import gzip |
||||
import os |
||||
try: |
||||
import subprocess |
||||
has_subprocess = True |
||||
except: |
||||
has_subprocess = False |
||||
|
||||
|
||||
class super_file(object): |
||||
'''"Super-file" hack wrapper for a file-like object. |
||||
Intended to allow extra capabilities to file-like iterators such as: |
||||
* ability to push back text lines for the subsequent next() calls. |
||||
This is to provide some level of rewinding in parsing text files. |
||||
* what else? |
||||
''' |
||||
def __init__(self, obj): |
||||
'''Creates a super_file wrapper around the "obj" object.''' |
||||
self.obj = obj |
||||
self.pushback = [] |
||||
def __iter__(self): |
||||
return self |
||||
def close(self): |
||||
return self.obj.close() |
||||
def flush(self): |
||||
return self.obj.flush() |
||||
def next(self): |
||||
if len(self.pushback) > 0: |
||||
return self.pushback.pop() |
||||
else: |
||||
return self.obj.next() |
||||
def push(self, s): |
||||
self.pushback.append(s) |
||||
|
||||
|
||||
def open_input_file(fname, superize=0): |
||||
if fname.endswith(".bz2"): |
||||
fobj = bz2.BZ2File(fname, "r") |
||||
elif fname.endswith(".gz") or fname.endswith(".Z"): |
||||
fobj = gzip.GzipFile(fname, "r") |
||||
elif fname.endswith(".lzma"): |
||||
# until lzma has a "standard" python module, we use "lzma" executable: |
||||
if has_subprocess: |
||||
px = subprocess.Popen(("lzma", "-dc", fname), stdout=subprocess.PIPE) |
||||
fobj = px.stdout |
||||
else: |
||||
px = os.popen('lzma -dc "' + fname + '"', "r") |
||||
else: |
||||
fobj = open(fname, "r") |
||||
|
||||
if superize: |
||||
return super_file(fobj) |
||||
else: |
||||
return fobj |
||||
|
||||
|
||||
# Miscellaneous functions |
||||
|
||||
def glob_files(filespec): |
||||
'''Processes a glob string, or does nothing (pass-on only) if an iterable object |
||||
(e.g. list or tuple) is already given. |
||||
When globbing is done, the result is sorted for predictability.''' |
||||
if getattr(filespec, "__iter__", False): |
||||
return filespec # no re-sorting |
||||
elif isinstance(filespec, str): |
||||
return sorted(glob.glob(filespec)) |
||||
else: |
||||
raise ValueError, "Don't know how to glob for an object of " + type(filespec) |
||||
|
||||
|
||||
def path_search(*specs, **opts): |
||||
'''Generalized path search. |
||||
Multiple paths can be specified for different parts of the sought filename, |
||||
and the first file found is returned. |
||||
|
||||
Additional options: |
||||
* pathsep="/" -- path separator |
||||
* filetest=os.path.isfile -- filetest operator to be used |
||||
* raise_error=False -- do we want to raise an exception if the file |
||||
is not found? |
||||
''' |
||||
# FIXME: this can be extremely expensive! |
||||
xspecs = [] |
||||
xlen = [] |
||||
xstride = [] |
||||
xtot = 1 |
||||
pathsep = opts.get("pathsep", "/") |
||||
filetest = opts.get("filetest", os.path.isfile) |
||||
|
||||
for spec in specs: |
||||
if not getattr(spec, "__iter__", False): |
||||
xspecs.append((spec,)) |
||||
xlen.append(1) |
||||
else: |
||||
xspecs.append(tuple([ x for x in spec ])) |
||||
xlen.append(len(xspecs[-1])) |
||||
xstride.append(xtot) |
||||
xtot *= xlen[-1] |
||||
|
||||
for idx in xrange(xtot): |
||||
idx0 = idx |
||||
# Construct the filename based on the index: we reconstruct |
||||
# the indices for all the parts given in the argument, then |
||||
# concatenate them to get the full pathname |
||||
s = "" |
||||
for d in xrange(len(xspecs)-1,-1,-1): |
||||
a = idx0 / xstride[d] |
||||
if s == "": |
||||
s = xspecs[d][a] |
||||
else: |
||||
s = xspecs[d][a] + pathsep + s |
||||
idx0 = idx0 % xstride[d] |
||||
#print a, |
||||
#print s |
||||
if filetest(s): |
||||
return s |
||||
|
||||
if opts.get("raise_error", False): |
||||
raise ValueError, "Cannot find file with specified combination" |
||||
else: |
||||
return None |
||||
|
||||
|
||||
def untar(archive, subdir=None, verbose=None, files=[]): |
||||
'''Extracts a TAR archive. The destination directory can be given; otherwise |
||||
the files are extracted to the current directory. |
||||
Assuming GNU tar which accepts -z and -j switches. |
||||
LZMA compression is supported via lzma program. |
||||
''' |
||||
opts = [ 'tar' ] |
||||
# Python doc says: "the arguments to the child process must start with the |
||||
# name of the command being run" |
||||
|
||||
if subdir: |
||||
opts += [ "-C", subdir ] |
||||
|
||||
if archive.endswith(".tar.bz2") or archive.endswith(".tbz2") or archive.endswith(".tbz"): |
||||
opts.append("-j") |
||||
elif archive.endswith(".tar.Z") or archive.endswith(".tar.gz") or archive.endswith(".tgz"): |
||||
opts.append("-z") |
||||
elif archive.endswith(".tar.lzma") or archive.endswith(".tza"): |
||||
opts.append("--use-compress-program=lzma") |
||||
|
||||
if verbose: |
||||
for i in xrange(verbose): opts.append("-v") |
||||
|
||||
opts += [ "-xf", archive ] |
||||
opts += files |
||||
|
||||
return os.spawnvp(os.P_WAIT, "tar", opts) |
||||
|
||||
|
Loading…
Reference in new issue