void
storage_t::drop_subscription_for_all_states(
const mbox_t & mbox,
const std::type_index & msg_type )
{
const is_same_mbox_msg is_same{ mbox->id(), msg_type };
auto lower_bound = m_events.lower_bound(
key_t{ mbox->id(), msg_type, nullptr } );
auto need_erase = [&] {
return lower_bound != std::end(m_events) &&
is_same( lower_bound->first );
};
const bool events_found = need_erase();
if( events_found )
{
do
{
m_events.erase( lower_bound++ );
}
while( need_erase() );
// Note: since v.5.5.9 mbox unsubscription is initiated even if
// it is MPSC mboxes. It is important for the case of message
// delivery tracing.
mbox->unsubscribe_event_handlers( msg_type, owner() );
}
}
void
storage_t::drop_subscription(
const mbox_t & mbox,
const std::type_index & msg_type,
const state_t & target_state )
{
auto existed_position = find(
m_events, mbox->id(), msg_type, target_state );
if( existed_position != m_events.end() )
{
// Note v.5.5.9 unsubscribe_event_handlers is called for
// mbox even if it is MPSC mbox. It is necessary for the case
// of message delivery tracing.
// We must destroy mbox subscription in case if the agent has no
// more subscriptions for that mbox+msg_type pair.
// Detect this while existed_position is not invalidated.
bool must_unsubscribe_mbox =
!is_known_mbox_msg_pair( m_events, existed_position );
m_events.erase( existed_position );
if( must_unsubscribe_mbox )
{
mbox->unsubscribe_event_handlers( msg_type, owner() );
}
}
}
void
storage_t::drop_subscription_for_all_states(
const mbox_t & mbox_ref,
const std::type_index & type_index )
{
const key_t key( mbox_ref->id(), type_index );
auto it = m_map.lower_bound( key );
auto need_erase = [&] {
return it != m_map.end() &&
key.is_same_mbox_msg_pair( it->first );
};
const bool found = need_erase();
if( found )
{
do
{
m_hash_table.erase( &(it->first) );
m_map.erase( it++ );
}
while( need_erase() );
mbox_ref->unsubscribe_event_handlers( type_index, owner() );
}
}
void
storage_t::create_event_subscription(
const mbox_t & mbox,
const std::type_index & msg_type,
const message_limit::control_block_t * limit,
const state_t & target_state,
const event_handler_method_t & method,
thread_safety_t thread_safety )
{
using namespace std;
using namespace subscription_storage_common;
const auto mbox_id = mbox->id();
// Check that this subscription is new.
auto existed_position = find(
m_events, mbox_id, msg_type, target_state );
if( existed_position != m_events.end() )
SO_5_THROW_EXCEPTION(
rc_evt_handler_already_provided,
"agent is already subscribed to message, " +
make_subscription_description( mbox, msg_type, target_state ) );
// Just add subscription to the end.
auto ins_result = m_events.emplace(
subscr_map_t::value_type {
key_t { mbox_id, msg_type, &target_state },
value_t {
mbox,
event_handler_data_t { method, thread_safety }
}
} );
// Note: since v.5.5.9 mbox subscription is initiated even if
// it is MPSC mboxes. It is important for the case of message
// delivery tracing.
// If there was no subscription for that mbox
// then new subscription in the mbox must be created.
if( !is_known_mbox_msg_pair( m_events, ins_result.first ) )
{
so_5::details::do_with_rollback_on_exception(
[&] {
mbox->subscribe_event_handler(
msg_type,
limit,
owner() );
},
[&] {
m_events.erase( ins_result.first );
} );
}
}
/*!
* \since v.5.5.3
* \brief A helper function for creating subscription description.
*/
inline std::string
make_subscription_description(
const mbox_t & mbox_ref,
std::type_index msg_type,
const state_t & state )
{
std::ostringstream s;
s << "(mbox:'" << mbox_ref->query_name()
<< "', msg_type:'" << msg_type.name() << "', state:'"
<< state.query_name() << "')";
return s.str();
}