Package: python-debian
Version: 0.1.14ubuntu2
Severity: normal
Tags: patch
Currently (tested using trunk), ArFile assumes that it will always receive a
filename, and that filename relates to the local filesystem.
This means that, when instantiating a DebFile using only a fileobj parameter,
you get something like:
>>> from debian import debfile
>>> package = debfile.DebFile(fileobj=open('some-package.deb', 'r'))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File
"/usr/local/lib/python2.6/dist-packages/python_debian-_CHANGELOG_VERSION_-py2.6.egg/debian/debfile.py",
line 236, in __init__
self.__version = f.read().strip()
File
"/usr/local/lib/python2.6/dist-packages/python_debian-_CHANGELOG_VERSION_-py2.6.egg/debian/arfile.py",
line 211, in read
self.__fp = open(self.__fname, "r")
TypeError: coercing to Unicode: need string or buffer, NoneType found
The solution I've come up with will involve DebFile sharing the fileobj among
several ArFile instances (is there a way to clone file-like objects?), which
means ArFiles keep an internal seek-location, and don't actually close() the
file pointer (leaky?).
A patch should be attached, or there is my fork on GitHub:
https://github.com/Raumkraut/python-debian
-- System Information:
Debian Release: squeeze/sid
APT prefers lucid-updates
APT policy: (500, 'lucid-updates'), (500, 'lucid-security'), (500, 'lucid')
Architecture: i386 (i686)
Kernel: Linux 2.6.32-33-generic-pae (SMP w/2 CPU cores)
Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Versions of packages python-debian depends on:
ii python 2.6.5-0ubuntu1 An interactive high-level object-o
ii python-apt 0.7.94.2ubuntu6.4 Python interface to libapt-pkg
ii python-support 1.0.4ubuntu1 automated rebuilding support for P
python-debian recommends no packages.
Versions of packages python-debian suggests:
ii gpgv 1.4.10-2ubuntu1 GNU privacy guard - signature veri
diff --git a/lib/debian/arfile.py b/lib/debian/arfile.py
index 9ad757e..d881e5f 100644
--- a/lib/debian/arfile.py
+++ b/lib/debian/arfile.py
@@ -159,6 +159,7 @@ class ArMember(object):
self.__fp = None # file pointer
self.__offset = None # start-of-data offset
self.__end = None # end-of-data offset
+ self.__cur = None # current seek-location (for shared fp)
def from_file(fp, fname):
"""fp is an open File object positioned on a valid file header inside
@@ -198,51 +199,68 @@ class ArMember(object):
f.__fname = fname
f.__offset = fp.tell() # start-of-data
f.__end = f.__offset + f.__size
-
+
+ if fname is None:
+ f.__fp = fp
+ f.__cur = f.__offset
+
return f
from_file = staticmethod(from_file)
- # file interface
-
- # XXX this is not a sequence like file objects
- def read(self, size=0):
+ def _init_fp(self):
+ """Readies the file pointer. """
if self.__fp is None:
+ # We have just a filename, so open it (one time)
self.__fp = open(self.__fname, "r")
self.__fp.seek(self.__offset)
+
+ elif self.__fname is None:
+ # Nameless (possibly shared) file-like object
+ self.__fp.seek(self.__cur)
+
+ def _update_cur(self):
+ """Update our current position. """
+ self.__cur = self.__fp.tell()
+
+ # file interface
- cur = self.__fp.tell()
-
- if size > 0 and size <= self.__end - cur: # there's room
- return self.__fp.read(size)
+ # XXX this is not a sequence like file objects
+ def read(self, size=0):
+ self._init_fp()
- if cur >= self.__end or cur < self.__offset:
- return ''
+ if size > 0 and size <= self.__end - self.__cur: # there's room
+ ret = self.__fp.read(size)
- return self.__fp.read(self.__end - cur)
+ elif self.__cur >= self.__end or self.__cur < self.__offset:
+ ret = ''
+
+ else:
+ ret = self.__fp.read(self.__end - self.__cur)
+
+ self._update_cur()
+ return ret
def readline(self, size=None):
- if self.__fp is None:
- self.__fp = open(self.__fname, "r")
- self.__fp.seek(self.__offset)
-
+ self._init_fp()
+
if size is not None:
buf = self.__fp.readline(size)
- if self.__fp.tell() > self.__end:
+ self._update_cur()
+ if self.__cur > self.__end:
return ''
return buf
buf = self.__fp.readline()
- if self.__fp.tell() > self.__end:
+ self._update_cur()
+ if self.__cur > self.__end:
return ''
else:
return buf
def readlines(self, sizehint=0):
- if self.__fp is None:
- self.__fp = open(self.__fname, "r")
- self.__fp.seek(self.__offset)
+ self._init_fp()
buf = None
lines = []
@@ -255,11 +273,9 @@ class ArMember(object):
return lines
def seek(self, offset, whence=0):
- if self.__fp is None:
- self.__fp = open(self.__fname, "r")
- self.__fp.seek(self.__offset)
+ self._init_fp()
- if self.__fp.tell() < self.__offset:
+ if self.__cur < self.__offset:
self.__fp.seek(self.__offset)
if whence < 2 and offset + self.__fp.tell() < self.__offset:
@@ -271,20 +287,21 @@ class ArMember(object):
self.__fp.seek(self.__offset + offset, 0)
elif whence == 2:
self.__fp.seek(self.__end + offset, 0)
+
+ self._update_cur()
def tell(self):
- if self.__fp is None:
- self.__fp = open(self.__fname, "r")
- self.__fp.seek(self.__offset)
+ self._init_fp()
- cur = self.__fp.tell()
-
- if cur < self.__offset:
+ if self.__cur < self.__offset:
return 0L
else:
- return cur - self.__offset
+ return self.__cur - self.__offset
def close(self):
+ if self.__fname is None:
+ # NB. self.__fp might be shared. Leaky to never explicitly close?
+ return
if self.__fp is not None:
self.__fp.close()
diff --git a/tests/test_debfile.py b/tests/test_debfile.py
index b37dfd7..1385cc4 100755
--- a/tests/test_debfile.py
+++ b/tests/test_debfile.py
@@ -98,6 +98,11 @@ class TestArFile(unittest.TestCase):
m.close()
f.close()
+class TestArFileObj(TestArFile):
+ def setUp(self):
+ TestArFile.setUp(self)
+ self.a = arfile.ArFile(fileobj=open("test.ar", "r"))
+
class TestDebFile(unittest.TestCase):
def setUp(self):
