When an unfinished generator-iterator is garbage collected, PyEval_EvalFrameEx
is called with a GeneratorExit exception set.  This leads to funny results
if the sys.settrace function itself makes use of generators.
A visible effect is that the settrace function is reset to None.
Another is that the eventual "finally" block of the generator is not called.

It is necessary to save/restore the exception around the call to the trace
function.

This happens a lot with py3k: isinstance() of an ABCMeta instance runs
    def __instancecheck__(cls, instance):
        """Override for isinstance(instance, cls)."""
        return any(cls.__subclasscheck__(c)
                   for c in {instance.__class__, type(instance)})
which lets an opened generator expression each time it returns True.

And the problem can be reproduced in 2.5 with pure python code.

The C changes aren't quite the same as the patch given there; the test is.

Fix TextCalendar.prweek(). This closes issue #1427.

merge -r58935:58936 ../trunk

as being some form of 2.5.2 (this is admittedly a bit conservative);
we can make this 2.5.2c1 when making the release

* bump _bsddb patch version number.

Add missing "return NULL" in overflow check in PyString_Repr().

  Fixes Issue 1385: The hmac module now computes the correct hmac when using
  hashes with a block size other than 64 bytes (such as sha384 and sha512).

Backport fixes for the code that decodes octal escapes (and for PyString
also hex escapes) -- this was reaching beyond the end of the input string
buffer, even though it is not supposed to be \0-terminated.
This has no visible effect but is clearly the correct thing to do.
(In 3.0 it had a visible effect after removing ob_sstate from PyString.)
Also fixes #1098.

Undoes incorrect dbtables fix and errant strdup introduced as
described below:

r58757 | gregory.p.smith | 2007-11-01 14:08:14 -0700 (Thu, 01 Nov 2007) | 4 lines

Fix bug introduced in revision 58385.  Database keys could no longer
have NULL bytes in them.  Replace the errant strdup with a
malloc+memcpy.  Adds a unit test for the correct behavior.

r58758 | gregory.p.smith | 2007-11-01 14:15:36 -0700 (Thu, 01 Nov 2007) | 3 lines

Undo revision 58533 58534 fixes.  Those were a workaround for
a problem introduced by 58385.

r58759 | gregory.p.smith | 2007-11-01 14:17:47 -0700 (Thu, 01 Nov 2007) | 2 lines

false "fix" undone as correct problem was found and fixed.

Issue 1307 by Derek Shockey, fix the same bug for RCPT.

Issue #1307, patch by Derek Shockey.
When "MAIL" is received without args, an exception happens instead of
sending a 501 syntax error response.

 - Fix bsddb.dbtables: Don't randomly corrupt newly inserted rows by
   picking a rowid string with null bytes in it.  Such rows could not
   later be deleted, modified or individually selected.  Existing
   bsdTableDb databases created with such rows are out of luck.
 - Use mkdtemp for the test_dbtables test database environment and
   clean it up afterwards using shutil.rmtree.

Fixes http://bugs.python.org/issue1233 - bsddb.dbshelve.DBShelf.append
was useless due to inverted logic.  Also adds a test case for RECNO dbs
to test_dbshelve.

See also https://bugs.launchpad.net/bugs/72505.

Fix Coverity 185-186:  If the passed in FILE is NULL, uninitialized memory
would be accessed.

on DBCursor.get (and a friends) when passing in a string key.

This code was broken if save() returned a negative number since i contained
a boolean value and then we compared i < 0 which should never be true.