metadatareader: error return without exception set

[sascha_silbe]

I'm getting the following error (in shell.log) two times during startup on an ARM/EABI system (but not on an i386 system):

Traceback (most recent call last):
  File "/home/sascha.silbe/sugar-jhbuild/install/lib/python2.5/site-packages/jarabe/journal/listmodel.py", line 108, in on_iter_n_children
    return self._result_set.length
  File "/home/sascha.silbe/sugar-jhbuild/install/lib/python2.5/site-packages/jarabe/journal/model.py", line 107, in get_length
    entries, self._total_count = self.find(query)
  File "/home/sascha.silbe/sugar-jhbuild/install/lib/python2.5/site-packages/jarabe/journal/model.py", line 222, in find
    byte_arrays=True)
  File "/usr/lib/pymodules/python2.5/dbus/proxies.py", line 140, in __call__
    **keywords)
  File "/usr/lib/pymodules/python2.5/dbus/connection.py", line 622, in call_blocking
    message, timeout)
dbus.exceptions.DBusException: org.freedesktop.DBus.Python.SystemError: Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.5/dbus/service.py", line 702, in _message_cb
    retval = candidate_method(self, *args, **keywords)
  File "/home/sascha.silbe/sugar-jhbuild/install/lib/python2.5/site-packages/carquinyol/datastore.py", line 228, in find
    metadata = self._metadata_store.retrieve(uid, properties)
  File "/home/sascha.silbe/sugar-jhbuild/install/lib/python2.5/site-packages/carquinyol/metadatastore.py", line 39, in retrieve
    return metadatareader.retrieve(metadata_path, properties)
SystemError: error return without exception set

To reproduce from outside Sugar:

sascha.silbe@flatty:~/sugar-jhbuild$ dbus-launch ./sugar-jhbuild run python
Warning: unknown distro version, automatic fallback to unstable.
Python 2.5.4 (r254:67916, Feb 18 2009, 07:14:14) 
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sugar.datastore.dbus_helpers
>>> sugar.datastore.dbus_helpers.find({'order_by': ['+timestamp'], 'limit': 30}, ['fdjkfd'], None, None)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/sascha.silbe/sugar-jhbuild/install/lib/python2.5/site-packages/sugar/datastore/dbus_helpers.py", line 94, in find
    return _get_data_store().find(query, properties, byte_arrays=True)
  File "/usr/lib/pymodules/python2.5/dbus/proxies.py", line 68, in __call__
    return self._proxy_method(*args, **keywords)
  File "/usr/lib/pymodules/python2.5/dbus/proxies.py", line 140, in __call__
    **keywords)
  File "/usr/lib/pymodules/python2.5/dbus/connection.py", line 622, in call_blocking
    message, timeout)
dbus.exceptions.DBusException: org.freedesktop.DBus.Python.SystemError: Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.5/dbus/service.py", line 702, in _message_cb
    retval = candidate_method(self, *args, **keywords)
  File "/home/sascha.silbe/sugar-jhbuild/install/lib/python2.5/site-packages/carquinyol/datastore.py", line 228, in find
    metadata = self._metadata_store.retrieve(uid, properties)
  File "/home/sascha.silbe/sugar-jhbuild/install/lib/python2.5/site-packages/carquinyol/metadatastore.py", line 39, in retrieve
    return metadatareader.retrieve(metadata_path, properties)
SystemError: error return without exception set

[sascha_silbe]

fix 'error return without exception set' on ARM

[sascha_silbe]

The previous code should never have been able to compile successfully. Probably some obscure feature of the C standard. :-/
Seems i386 and ARM have different "default return values" or whatever gets used in place of the missing value.

[sascha_silbe]

Hard code freeze exception granted by erikos on sugar-devel. Pushed as  http://git.sugarlabs.org/projects/sugar-datastore/repos/mainline/commits/3c5d44fcc52e5ffdefa01c2edb00ce6f0ff90564.

[sascha_silbe]

Affects 0.84 as well, needs to be backported.

[sascha_silbe]

backport to 0.84

[sascha_silbe]

0.86 commit could be applied as-is to 0.84 and works fine.
This happens at least on amd64 now, not just armel.

[alsroot]

v0.86.0 includes this patch.

[sascha_silbe]

I still don't see it in sucrose-0.84, so reopening again.

[alsroot]

cherry-picked to sucrose-0.84

[sascha_silbe]

Thanks!