Merge with 3.5: Issue #24514: tarfile now tolerates number fields consisting of only whitespace.

Lib/tarfile.py

@@ -178,7 +178,8 @@ def nti(s):
             n = -(256 ** (len(s) - 1) - n)
     else:
         try:
-            n = int(nts(s, "ascii", "strict") or "0", 8)
+            s = nts(s, "ascii", "strict")
+            n = int(s.strip() or "0", 8)
         except ValueError:
             raise InvalidHeaderError("invalid header")
     return n

Lib/test/test_tarfile.py

@@ -1952,6 +1952,10 @@ class MiscTest(unittest.TestCase):
         self.assertEqual(tarfile.nti(b"\xff\x00\x00\x00\x00\x00\x00\x00"),
                          -0x100000000000000)
 
+        # Issue 24514: Test if empty number fields are converted to zero.
+        self.assertEqual(tarfile.nti(b"\0"), 0)
+        self.assertEqual(tarfile.nti(b"       \0"), 0)
+
     def test_write_number_fields(self):
         self.assertEqual(tarfile.itn(1), b"0000001\x00")
         self.assertEqual(tarfile.itn(0o7777777), b"7777777\x00")

Misc/NEWS

@@ -52,6 +52,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #24514: tarfile now tolerates number fields consisting of only
+  whitespace.
+
 - Issue #19176: Fixed doctype() related bugs in C implementation of ElementTree.
   A deprecation warning no longer issued by XMLParser subclass with default
   doctype() method.  Direct call of doctype() now issues a warning.  Parser's