Currently, sgsn_update_subscriber_data can be called with mmctx ==
NULL and will find and associate the right context (if present) based
on the subscriber's IMSI. This will not happen in regular use
any more, since sgsn_update_subscriber_data will only be called when
subscribers are used (auth mode 'remote') and in this case
gprs_subscr_get_or_create_by_mmctx will already be called by
sgsn_auth_request. Therefore, MM context and subscriber are always
associated except for some test cases and experimental VTY usage.
The current implementation of sgsn_update_subscriber_data also causes
additional complexity for the deletion on MM contexts to avoid a
ipossible double-free MM contexts.
This commit removes the MM context <-> subscriber association code
from sgsn_update_subscriber_data. That function must always be called
with mmctx != NULL, now. To avoid problems with VTY and test usage,
the calling subscriber function now only call
sgsn_update_subscriber_data when mmctx != NULL, since the purpose of
that function is to update that state of an existing MM context after
subscriber data has been changed.
Sponsored-by: On-Waves ehf
555b2e5ac1