diff options
| -rw-r--r-- | Doc/library/zipfile.rst | 4 | ||||
| -rw-r--r-- | Lib/test/test_zipfile.py | 25 | ||||
| -rw-r--r-- | Lib/zipfile.py | 27 | ||||
| -rw-r--r-- | Misc/NEWS | 4 |
4 files changed, 55 insertions, 5 deletions
diff --git a/Doc/library/zipfile.rst b/Doc/library/zipfile.rst index 33f58b2..bd6c3a6 100644 --- a/Doc/library/zipfile.rst +++ b/Doc/library/zipfile.rst @@ -122,6 +122,10 @@ ZipFile Objects and :program:`unzip` commands on Unix (the InfoZIP utilities) don't support these extensions. + If the file is created with mode ``'a'`` or ``'w'`` and then + :meth:`close`\ d without adding any files to the archive, the appropriate + ZIP structures for an empty archive will be written to the file. + ZipFile is also a context manager and therefore supports the :keyword:`with` statement. In the example, *myzip* is closed after the :keyword:`with` statement's suite is finished---even if an exception occurs:: diff --git a/Lib/test/test_zipfile.py b/Lib/test/test_zipfile.py index aee499c..ddd713f 100644 --- a/Lib/test/test_zipfile.py +++ b/Lib/test/test_zipfile.py @@ -949,6 +949,31 @@ class OtherTests(unittest.TestCase): def test_read_return_size_deflated(self): self.check_read_return_size(zipfile.ZIP_DEFLATED) + def test_empty_zipfile(self): + # Check that creating a file in 'w' or 'a' mode and closing without + # adding any files to the archives creates a valid empty ZIP file + zipf = zipfile.ZipFile(TESTFN, mode="w") + zipf.close() + try: + zipf = zipfile.ZipFile(TESTFN, mode="r") + except zipfile.BadZipFile: + self.fail("Unable to create empty ZIP file in 'w' mode") + + zipf = zipfile.ZipFile(TESTFN, mode="a") + zipf.close() + try: + zipf = zipfile.ZipFile(TESTFN, mode="r") + except: + self.fail("Unable to create empty ZIP file in 'a' mode") + + def test_open_empty_file(self): + # Issue 1710703: Check that opening a file with less than 22 bytes + # raises a BadZipfile exception (rather than the previously unhelpful + # IOError) + f = open(TESTFN, 'w') + f.close() + self.assertRaises(zipfile.BadZipfile, zipfile.ZipFile, TESTFN, 'r') + def tearDown(self): unlink(TESTFN) unlink(TESTFN2) diff --git a/Lib/zipfile.py b/Lib/zipfile.py index 496cf83..7e3caf0 100644 --- a/Lib/zipfile.py +++ b/Lib/zipfile.py @@ -158,7 +158,13 @@ def _EndRecData64(fpin, offset, endrec): """ Read the ZIP64 end-of-archive records and use that to update endrec """ - fpin.seek(offset - sizeEndCentDir64Locator, 2) + try: + fpin.seek(offset - sizeEndCentDir64Locator, 2) + except IOError: + # If the seek fails, the file is not large enough to contain a ZIP64 + # end-of-archive record, so just return the end record we were given. + return endrec + data = fpin.read(sizeEndCentDir64Locator) sig, diskno, reloff, disks = struct.unpack(structEndArchive64Locator, data) if sig != stringEndArchive64Locator: @@ -705,14 +711,22 @@ class ZipFile: if key == 'r': self._GetContents() elif key == 'w': - pass + # set the modified flag so central directory gets written + # even if no files are added to the archive + self._didModify = True elif key == 'a': - try: # See if file is a zip file + try: + # See if file is a zip file self._RealGetContents() # seek to start of directory and overwrite self.fp.seek(self.start_dir, 0) - except BadZipfile: # file is not a zip file, just append + except BadZipfile: + # file is not a zip file, just append self.fp.seek(0, 2) + + # set the modified flag so central directory gets written + # even if no files are added to the archive + self._didModify = True else: if not self._filePassed: self.fp.close() @@ -739,7 +753,10 @@ class ZipFile: def _RealGetContents(self): """Read in the table of contents for the ZIP file.""" fp = self.fp - endrec = _EndRecData(fp) + try: + endrec = _EndRecData(fp) + except IOError: + raise BadZipfile("File is not a zip file") if not endrec: raise BadZipfile, "File is not a zip file" if self.debug > 1: @@ -15,6 +15,10 @@ Library - Issue #10459: Update CJK character names to Unicode 5.2. +- Issue #1710703: Write structures for an empty ZIP archive when a ZipFile is + created in modes 'a' or 'w' and then closed without adding any files. Raise + BadZipfile (rather than IOError) when opening small non-ZIP files. + - Issue #4493: urllib2 adds '/' in front of path components which does not start with '/. Common behavior exhibited by browsers and other clients. |