[issue9720] zipfile writes incorrect local file header for large files in zip64
Roundup Robot added the comment: New changeset ce869b05762c by Serhiy Storchaka in branch '2.7': Issue #9720: zipfile now writes correct local headers for files larger than 4 GiB. http://hg.python.org/cpython/rev/ce869b05762c New changeset b93848ca7760 by Serhiy Storchaka in branch '3.2': Issue #9720: zipfile now writes correct local headers for files larger than 4 GiB. http://hg.python.org/cpython/rev/b93848ca7760 New changeset 656a45738e5e by Serhiy Storchaka in branch '3.3': Issue #9720: zipfile now writes correct local headers for files larger than 4 GiB. http://hg.python.org/cpython/rev/656a45738e5e New changeset 628a6af64a46 by Serhiy Storchaka in branch 'default': Issue #9720: zipfile now writes correct local headers for files larger than 4 GiB. http://hg.python.org/cpython/rev/628a6af64a46 -- nosy: +python-dev ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Serhiy Storchaka added the comment: Fixed. Thank you for report, Craig de Stigter. -- resolution: - fixed stage: patch review - committed/rejected status: open - closed ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Nico Möller added the comment: I most definitely need a patch for 2.7.3 Would be awesome if you could provide a patch for that version. -- nosy: +Nico.Möller ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Serhiy Storchaka added the comment:
Here are second variant patches for 2.7 and 3.2.
--
Added file: http://bugs.python.org/file28558/zipfile_zip64_try_2-2.7.patch
Added file: http://bugs.python.org/file28559/zipfile_zip64_try_2-3.2.patch
___
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http://bugs.python.org/issue9720
___diff -r c8e885ecbc89 Lib/zipfile.py
--- a/Lib/zipfile.pyThu Jan 03 20:34:19 2013 -0800
+++ b/Lib/zipfile.pyFri Jan 04 15:24:35 2013 +0200
@@ -316,7 +316,7 @@
# compress_size Size of the compressed file
# file_size Size of the uncompressed file
-def FileHeader(self):
+def FileHeader(self, zip64=None):
Return the per-file header as a string.
dt = self.date_time
dosdate = (dt[0] - 1980) 9 | dt[1] 5 | dt[2]
@@ -331,12 +331,17 @@
extra = self.extra
-if file_size ZIP64_LIMIT or compress_size ZIP64_LIMIT:
-# File is larger than what fits into a 4 byte integer,
-# fall back to the ZIP64 extension
+if zip64 is None:
+zip64 = file_size ZIP64_LIMIT or compress_size ZIP64_LIMIT
+if zip64:
fmt = 'HHQQ'
extra = extra + struct.pack(fmt,
1, struct.calcsize(fmt)-4, file_size, compress_size)
+if file_size ZIP64_LIMIT or compress_size ZIP64_LIMIT:
+if not zip64:
+raise LargeZipFile(Filesize would require ZIP64 extensions)
+# File is larger than what fits into a 4 byte integer,
+# fall back to the ZIP64 extension
file_size = 0x
compress_size = 0x
self.extract_version = max(45, self.extract_version)
@@ -1113,20 +1118,23 @@
zinfo.CRC = 0
self.filelist.append(zinfo)
self.NameToInfo[zinfo.filename] = zinfo
-self.fp.write(zinfo.FileHeader())
+self.fp.write(zinfo.FileHeader(False))
return
with open(filename, rb) as fp:
# Must overwrite CRC and sizes with correct data later
zinfo.CRC = CRC = 0
zinfo.compress_size = compress_size = 0
-zinfo.file_size = file_size = 0
-self.fp.write(zinfo.FileHeader())
+# Compressed size can be larger than uncompressed size
+zip64 = self._allowZip64 and \
+zinfo.file_size * 1.05 ZIP64_LIMIT
+self.fp.write(zinfo.FileHeader(zip64))
if zinfo.compress_type == ZIP_DEFLATED:
cmpr = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
zlib.DEFLATED, -15)
else:
cmpr = None
+file_size = 0
while 1:
buf = fp.read(1024 * 8)
if not buf:
@@ -1146,11 +1154,16 @@
zinfo.compress_size = file_size
zinfo.CRC = CRC
zinfo.file_size = file_size
-# Seek backwards and write CRC and file sizes
+if not zip64 and self._allowZip64:
+if file_size ZIP64_LIMIT:
+raise RuntimeError('File size has increased during
compressing')
+if compress_size ZIP64_LIMIT:
+raise RuntimeError('Compressed size larger than uncompressed
size')
+# Seek backwards and write file header (which will now include
+# correct CRC and file sizes)
position = self.fp.tell() # Preserve current position in file
-self.fp.seek(zinfo.header_offset + 14, 0)
-self.fp.write(struct.pack(LLL, zinfo.CRC, zinfo.compress_size,
- zinfo.file_size))
+self.fp.seek(zinfo.header_offset, 0)
+self.fp.write(zinfo.FileHeader(zip64))
self.fp.seek(position, 0)
self.filelist.append(zinfo)
self.NameToInfo[zinfo.filename] = zinfo
@@ -1187,14 +1200,18 @@
zinfo.compress_size = len(bytes)# Compressed size
else:
zinfo.compress_size = zinfo.file_size
-zinfo.header_offset = self.fp.tell()# Start of header bytes
-self.fp.write(zinfo.FileHeader())
+zip64 = zinfo.file_size ZIP64_LIMIT or \
+zinfo.compress_size ZIP64_LIMIT
+if zip64 and not self._allowZip64:
+raise LargeZipFile(Filesize would require ZIP64 extensions)
+self.fp.write(zinfo.FileHeader(zip64))
self.fp.write(bytes)
-self.fp.flush()
if zinfo.flag_bits 0x08:
# Write CRC and file sizes after the file data
-self.fp.write(struct.pack(LLL, zinfo.CRC, zinfo.compress_size,
+fmt = 'LQQ' if zip64 else 'LLL'
+self.fp.write(struct.pack(fmt, zinfo.CRC, zinfo.compress_size,
zinfo.file_size))
+self.fp.flush()
self.filelist.append(zinfo)
self.NameToInfo[zinfo.filename] =
[issue9720] zipfile writes incorrect local file header for large files in zip64
Serhiy Storchaka added the comment: What variant of patches should I commit? Or prepare other? -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Changes by Serhiy Storchaka storch...@gmail.com: -- assignee: - serhiy.storchaka ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Serhiy Storchaka added the comment: Patches updated to resolve merge conflict with issue11981. Please review and apply any of this patches. This is needed for some other my zipfile patches. -- Added file: http://bugs.python.org/file28145/zipfile_zip64_always_2.patch Added file: http://bugs.python.org/file28146/zipfile_zip64_try_2.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___diff -r 6f3d3003acf3 Lib/zipfile.py --- a/Lib/zipfile.pyWed Nov 28 12:34:27 2012 +0200 +++ b/Lib/zipfile.pyWed Nov 28 14:15:29 2012 +0200 @@ -346,7 +346,7 @@ # compress_size Size of the compressed file # file_size Size of the uncompressed file -def FileHeader(self): +def FileHeader(self, zip64=None): Return the per-file header as a string. dt = self.date_time dosdate = (dt[0] - 1980) 9 | dt[1] 5 | dt[2] @@ -362,12 +362,17 @@ extra = self.extra min_version = 0 -if file_size ZIP64_LIMIT or compress_size ZIP64_LIMIT: -# File is larger than what fits into a 4 byte integer, -# fall back to the ZIP64 extension +if zip64 is None: +zip64 = file_size ZIP64_LIMIT or compress_size ZIP64_LIMIT +if zip64: fmt = 'HHQQ' extra = extra + struct.pack(fmt, 1, struct.calcsize(fmt)-4, file_size, compress_size) +if file_size ZIP64_LIMIT or compress_size ZIP64_LIMIT: +if not zip64: +raise LargeZipFile(Filesize would require ZIP64 extensions) +# File is larger than what fits into a 4 byte integer, +# fall back to the ZIP64 extension file_size = 0x compress_size = 0x min_version = ZIP64_VERSION @@ -1301,7 +1306,7 @@ zinfo.CRC = 0 self.filelist.append(zinfo) self.NameToInfo[zinfo.filename] = zinfo -self.fp.write(zinfo.FileHeader()) +self.fp.write(zinfo.FileHeader(False)) return cmpr = _get_compressor(zinfo.compress_type) @@ -1309,8 +1314,9 @@ # Must overwrite CRC and sizes with correct data later zinfo.CRC = CRC = 0 zinfo.compress_size = compress_size = 0 -zinfo.file_size = file_size = 0 -self.fp.write(zinfo.FileHeader()) +# Compressed size can be larger than uncompressed size +self.fp.write(zinfo.FileHeader(self._allowZip64)) +file_size = 0 while 1: buf = fp.read(1024 * 8) if not buf: @@ -1330,11 +1336,11 @@ zinfo.compress_size = file_size zinfo.CRC = CRC zinfo.file_size = file_size -# Seek backwards and write CRC and file sizes +# Seek backwards and write file header (which will now include +# correct CRC and file sizes) position = self.fp.tell() # Preserve current position in file -self.fp.seek(zinfo.header_offset + 14, 0) -self.fp.write(struct.pack(LLL, zinfo.CRC, zinfo.compress_size, - zinfo.file_size)) +self.fp.seek(zinfo.header_offset, 0) +self.fp.write(zinfo.FileHeader(self._allowZip64)) self.fp.seek(position, 0) self.filelist.append(zinfo) self.NameToInfo[zinfo.filename] = zinfo @@ -1376,13 +1382,18 @@ zinfo.compress_size = len(data)# Compressed size else: zinfo.compress_size = zinfo.file_size -self.fp.write(zinfo.FileHeader()) +zip64 = zinfo.file_size ZIP64_LIMIT or \ +zinfo.compress_size ZIP64_LIMIT +if zip64 and not self._allowZip64: +raise LargeZipFile(Filesize would require ZIP64 extensions) +self.fp.write(zinfo.FileHeader(zip64)) self.fp.write(data) -self.fp.flush() if zinfo.flag_bits 0x08: # Write CRC and file sizes after the file data -self.fp.write(struct.pack(LLL, zinfo.CRC, zinfo.compress_size, +fmt = 'LQQ' if zip64 else 'LLL' +self.fp.write(struct.pack(fmt, zinfo.CRC, zinfo.compress_size, zinfo.file_size)) +self.fp.flush() self.filelist.append(zinfo) self.NameToInfo[zinfo.filename] = zinfo diff -r 6f3d3003acf3 Lib/zipfile.py --- a/Lib/zipfile.pyWed Nov 28 12:34:27 2012 +0200 +++ b/Lib/zipfile.pyWed Nov 28 14:15:50 2012 +0200 @@ -346,7 +346,7 @@ # compress_size Size of the compressed file # file_size Size of the uncompressed file -def FileHeader(self): +def FileHeader(self, zip64=None): Return the per-file header as a string. dt = self.date_time dosdate = (dt[0] - 1980) 9 | dt[1] 5 | dt[2] @@ -362,12 +362,17 @@
[issue9720] zipfile writes incorrect local file header for large files in zip64
Changes by Jon Henry jhe...@ccs.neu.edu: -- nosy: +jhenry82 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Serhiy Storchaka added the comment: Please, review the patches. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Changes by Ruben Gonzalez ruben...@teltek.es: -- nosy: +Ruben.Gonzalez ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Serhiy Storchaka added the comment: What the conclusion about the patches? Which variant I should backport for older versions? -- versions: +Python 3.4 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Ronald Oussoren added the comment: I'd write the extended header when the current file size is larger than the zip64 limit (that is, when 'st.st_size ZIP64_LIMIT' in the write method. That way the minimal header size is used whenever possible. As you noted this can cause problems when the file grows beyond the limit while it is stored in the zipfile, but IMHO storing data while it is modified is asking for problems anyway. BTW. I haven't actually review the patch yet. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Serhiy Storchaka added the comment: I see two rational solutions of the issue (all written below is applicable only for allowZip64=True): 1) Always write Zip64 extended information extra field. This approach always successful, but the zipfile size will increase by 20 bytes for each file. The first patch (zipfile_zip64_always.patch) uses this approach. 2) Write Zip64 extended information extra field only if assumed file size is more than a certain limit. In very rare cases this leads to the impossibility of compression of the file which can be compressed the first way. However it produces the same file as before patch in most cases. The second patch (zipfile_zip64_try.patch) is based on Alan's patch and uses the second approach. The probability of errors is reduced and they are now detected and does not lead to a silent data damage. Both patches are for Python 3.3. If any patch is good, I'll backport it for the older versions. -- nosy: +gregory.p.smith, loewis, ronaldoussoren Added file: http://bugs.python.org/file27262/zipfile_zip64_always.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Changes by Serhiy Storchaka storch...@gmail.com: -- stage: needs patch - patch review Added file: http://bugs.python.org/file27263/zipfile_zip64_try.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Serhiy Storchaka added the comment: No, on the contrary, it is not such easy to fix, and the patch is incorrect. Sorry that it is not clear either. The size of the header with extra args depends on the size of the file. The file size can be changed in the process of compressing, and compressed size may be larger than uncompressed size, exceeding 32-bit boundary. Rewriting the header with extra args, we can overwrite compressed data. I was put off the issue for further more careful research. Thanks for the reminder. One solution is always (even for smallest files) to write 64-bit sizes when allowZip64 is true. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Changes by Kristof Keppens kkepp...@gmail.com: -- nosy: +Kristof.Keppens ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Christian Heimes added the comment: Serhiy: If I understand you correctly it should be easy to fix. The code in close() has to check if any file is beyond the ZIP64 limit and then write all headers with extra args. Is that correct? -- keywords: +needs review nosy: +christian.heimes ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Changes by David Andrzejewski site+python@davidandrzejewski.com: -- nosy: +dandrzejewski ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Changes by Serhiy Storchaka storch...@gmail.com: -- nosy: +storchaka ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Serhiy Storchaka storch...@gmail.com added the comment: I am afraid that the problem is more complicated. With the option allowZip64=True all files need to write with this extension, because size of local file header may change and there will be after compression just go back and rewrite it. Now it appears that the Zip64 option simply does not work. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Nadeem Vawda nadeem.va...@gmail.com added the comment: Issue 6434 was marked as a duplicate of this issue. -- nosy: +Paul, amaury.forgeotdarc, enlavin, lambacck, nadeem.vawda, segfault42 stage: - needs patch versions: +Python 3.3 -Python 3.1 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
Re: [issue9720] zipfile writes incorrect local file header for large files in zip64
Alan McIntyre alan.mcint...@gmail.com added the comment: Here's an updated patch for the py3k trunk with tests. This pretty much doubles the runtime of test_zipfile64.py. The patch also removes some unnecessary code from the existing test_zipfile64 tests. Hello Alan I've faced this problem too. I start packing a 4.73GB file, and receive the struct error as follows: 1) Python 2.7.2 production: ... File C:\Python27\lib\zipfile.py, line 1100, in write zinfo.file_size)) struct.error: integer out of range for 'L' format code 2) Python 3.2 production: ... File C:\Python32\lib\zipfile.py, line 1142, in write zinfo.file_size)) struct.error: argument out of range Environment: Windows 7 Ultimate 32bit Everytime packing process fails at 4,981,808,577 byte I need a patch for Python 2.7.2 . Could you adapt your patch appropriately? Thanks. -- View this message in context: http://old.nabble.com/-issue9720--zipfile-writes-incorrect-local-file-header-for-large-files-in-zip64-tp29578646p31928738.html Sent from the Python - python-bugs-list mailing list archive at Nabble.com. ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Alan McIntyre alan.mcint...@gmail.com added the comment: Here's an updated patch for the py3k trunk with tests. This pretty much doubles the runtime of test_zipfile64.py. The patch also removes some unnecessary code from the existing test_zipfile64 tests. Note: It looks like writestr will also suffer from a struct.pack overflow if it's given a ZipInfo with the third general purpose flag bit set. I won't have time to address that until next weekend, probably. -- Added file: http://bugs.python.org/file18780/zipfile-huge-files.diff ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Alan McIntyre alan.mcint...@gmail.com added the comment: Thanks for the patch, Craig; I should have some time later today or tomorrow to do a review. Did you have a patch for the test suite(s) as well? If not, I can just make sure your test case is covered in test_zipfile64. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Craig de Stigter craig...@gmail.com added the comment: Hi, sorry no I haven't had time to add a real test for this -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Éric Araujo mer...@netwok.org added the comment: A tip about versions: Development happens on the current active branch, py3k (future 3.2 version), and bug or doc fixes are backported to the stable versions 2.7 and 3.1. Security fixes go into 2.6 too. Can you reproduce your bug in 2.7, 3.1 and 3.2? Adding Alan to nosy since he’s listed in Misc/maintainers.rst. -- nosy: +alanmcintyre, eric.araujo versions: -Python 2.5, Python 2.6, Python 3.3 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue9720 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue9720] zipfile writes incorrect local file header for large files in zip64
Craig de Stigter craig...@gmail.com added the comment:
Yes, the bug still exists in Python 3.1.2. However, struct.pack() no longer
silently ignores overflow, so I get this error instead:
z.write('foo.txt')
Traceback (most recent call last):
File stdin, line 1, in module
File /usr/lib/python3.1/zipfile.py, line 1095, in write
zinfo.file_size))
struct.error: argument out of range
--
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[issue9720] zipfile writes incorrect local file header for large files in zip64
New submission from Craig de Stigter craig...@gmail.com:
Steps to reproduce:
# create a large (4gb) file
f = open('foo.txt', 'wb')
text = 'a' * 1024**2
for i in xrange(5 * 1024):
f.write(text)
f.close()
# now zip the file
import zipfile
z = zipfile.ZipFile('foo.zip', mode='w', allowZip64=True)
z.write('foo.txt')
z.close()
Now inspect the file headers using a hex editor. The written headers are
incorrect. The filesize and compressed size should be written as 0x and
the 'extra field' should contain the actual sizes.
Tested on Python 2.5 but looking at the latest code in 3.2 it still looks
broken.
The problem is that the ZipInfo.FileHeader() is written before the filesize is
populated, so Zip64 extensions are not written. Later, the sizes in the header
are written, but Zip64 extensions are not taken into account and the filesize
is just wrapped (7gb becomes 3gb, for instance).
My patch fixes the problem on Python 2.5, it might need minor porting to fix
trunk. It works by assigning the uncompressed filesize to the ZipInfo header
initially, then writing the header. Then later on, I re-write the header (this
is okay since the header size will not have increased.)
--
components: Library (Lib)
files: zipfile_zip64_header.patch
keywords: patch
messages: 115250
nosy: craigds
priority: normal
severity: normal
status: open
title: zipfile writes incorrect local file header for large files in zip64
type: behavior
versions: Python 2.5, Python 2.6, Python 2.7, Python 3.1, Python 3.2, Python 3.3
Added file: http://bugs.python.org/file18685/zipfile_zip64_header.patch
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