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| author | Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> | 2023-08-24 10:30:16 (GMT) |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2023-08-24 10:30:16 (GMT) |
| commit | 20357ed2a434fc59a9cd33c162594e8f792813b4 (patch) | |
| tree | 99cf016bdddc97891d066bd767835189522848af | |
| parent | 459f24aef09dce122362ee2f234e97916cbf1e8d (diff) | |
| download | cpython-20357ed2a434fc59a9cd33c162594e8f792813b4.zip cpython-20357ed2a434fc59a9cd33c162594e8f792813b4.tar.gz cpython-20357ed2a434fc59a9cd33c162594e8f792813b4.tar.bz2 | |
[3.12] gh-108111: Flush gzip write buffer before seeking, fixing bad writes (GH-108341) (#108402)
gh-108111: Flush gzip write buffer before seeking, fixing bad writes (GH-108341)
(cherry picked from commit 2eb60c1934f47671e6b3c9b90b6d9f1912d829a0)
Co-authored-by: Chris Markiewicz <effigies@gmail.com>
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
| -rw-r--r-- | Lib/gzip.py | 3 | ||||
| -rw-r--r-- | Lib/test/test_gzip.py | 12 | ||||
| -rw-r--r-- | Misc/ACKS | 1 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2023-08-22-17-27-12.gh-issue-108111.N7a4u_.rst | 2 |
4 files changed, 18 insertions, 0 deletions
diff --git a/Lib/gzip.py b/Lib/gzip.py index cf8b675..177f908 100644 --- a/Lib/gzip.py +++ b/Lib/gzip.py @@ -401,6 +401,9 @@ class GzipFile(_compression.BaseStream): def seek(self, offset, whence=io.SEEK_SET): if self.mode == WRITE: + self._check_not_closed() + # Flush buffer to ensure validity of self.offset + self._buffer.flush() if whence != io.SEEK_SET: if whence == io.SEEK_CUR: offset = self.offset + offset diff --git a/Lib/test/test_gzip.py b/Lib/test/test_gzip.py index b06b3b0..128f933 100644 --- a/Lib/test/test_gzip.py +++ b/Lib/test/test_gzip.py @@ -665,6 +665,18 @@ class TestGzip(BaseTest): ] self.assertEqual(fc.modes, expected_modes) + def test_write_seek_write(self): + # Make sure that offset is up-to-date before seeking + # See issue GH-108111 + b = io.BytesIO() + message = b"important message here." + with gzip.GzipFile(fileobj=b, mode='w') as f: + f.write(message) + f.seek(len(message)) + f.write(message) + data = b.getvalue() + self.assertEqual(gzip.decompress(data), message * 2) + class TestOpen(BaseTest): def test_binary_modes(self): @@ -1149,6 +1149,7 @@ Colin Marc Vincent Marchetti David Marek Doug Marien +Chris Markiewicz Sven Marnach John Marshall Alex Martelli diff --git a/Misc/NEWS.d/next/Library/2023-08-22-17-27-12.gh-issue-108111.N7a4u_.rst b/Misc/NEWS.d/next/Library/2023-08-22-17-27-12.gh-issue-108111.N7a4u_.rst new file mode 100644 index 0000000..8eafa6c --- /dev/null +++ b/Misc/NEWS.d/next/Library/2023-08-22-17-27-12.gh-issue-108111.N7a4u_.rst @@ -0,0 +1,2 @@ +Fix a regression introduced in GH-101251 for 3.12, resulting in an incorrect +offset calculation in :meth:`gzip.GzipFile.seek`. |