[Python-checkins] cpython (2.7): Issue #11235: Fix OverflowError when trying to import a source file whose

Tue Jan 24 17:54:36 CET 2012

http://hg.python.org/cpython/rev/0499eed74126
changeset: 74598:0499eed74126
branch: 2.7
parent: 74584:f4f9ab2fd51b
user: Antoine Pitrou <solipsis at pitrou.net>
date: Tue Jan 24 17:44:06 2012 +0100
summary:
 Issue #11235: Fix OverflowError when trying to import a source file whose modification time doesn't fit in a 32-bit timestamp.
files:
 Lib/test/test_import.py | 13 +++++++++++++
 Misc/NEWS | 3 +++
 Python/import.c | 11 ++++-------
 3 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/Lib/test/test_import.py b/Lib/test/test_import.py
--- a/Lib/test/test_import.py
+++ b/Lib/test/test_import.py
@@ -277,6 +277,19 @@
 finally:
 os.rmdir(source)
 
+ def test_timestamp_overflow(self):
+ # A modification timestamp larger than 2**32 should not be a problem
+ # when importing a module (issue #11235).
+ source = TESTFN + ".py"
+ self.addCleanup(remove_files, TESTFN)
+ compiled = source + ('c' if __debug__ else 'o')
+ with open(source, 'w') as f:
+ pass
+ os.utime(source, (2 ** 33, 2 ** 33))
+ __import__(TESTFN)
+ # The pyc file was created.
+ os.stat(compiled)
+
 
 class PycRewritingTests(unittest.TestCase):
 # Test that the `co_filename` attribute on code objects always points
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -9,6 +9,9 @@
 Core and Builtins
 -----------------
 
+- Issue #11235: Fix OverflowError when trying to import a source file whose
+ modification time doesn't fit in a 32-bit timestamp.
+
 - Issue #11638: Unicode strings in 'name' and 'version' no longer cause
 UnicodeDecodeErrors.
 
diff --git a/Python/import.c b/Python/import.c
--- a/Python/import.c
+++ b/Python/import.c
@@ -981,14 +981,11 @@
 }
 #if SIZEOF_TIME_T > 4
 /* Python's .pyc timestamp handling presumes that the timestamp fits
- in 4 bytes. This will be fine until sometime in the year 2038,
- when a 4-byte signed time_t will overflow.
+ in 4 bytes. Since the code only does an equality comparison,
+ ordering is not important and we can safely ignore the higher bits
+ (collisions are extremely unlikely).
 */
- if (st.st_mtime >> 32) {
- PyErr_SetString(PyExc_OverflowError,
- "modification time overflows a 4 byte field");
- return NULL;
- }
+ st.st_mtime &= 0xFFFFFFFF;
 #endif
 cpathname = make_compiled_pathname(pathname, buf,
 (size_t)MAXPATHLEN + 1);
-- 
Repository URL: http://hg.python.org/cpython
