Event: QOF event handlers.
[Query Object Framework]

Files
file	gnc-event.h
	engine event handling interface (to be renamed qofevent.h in libqof2)
Typedefs
typedef void(*	GNCEngineEventHandler )(GUID *entity, QofIdType type, GNCEngineEventType event_type, gpointer user_data)
Enumerations
enum	GNCEngineEventType {   GNC_EVENT_NONE = 0, GNC_EVENT_CREATE = 1 << 0, GNC_EVENT_MODIFY = 1 << 1, GNC_EVENT_DESTROY = 1 << 2,   GNC_EVENT_ADD = 1 << 3, GNC_EVENT_REMOVE = 1 << 4, GNC_EVENT_ALL = 0xff }
Functions
gint	gnc_engine_register_event_handler (GNCEngineEventHandler handler, gpointer user_data)
void	gnc_engine_unregister_event_handler (gint handler_id)
void	gnc_engine_gen_event (QofEntity *entity, GNCEngineEventType event_type)
void	gnc_engine_suspend_events (void)
void	gnc_engine_resume_events (void)

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Typedef Documentation

typedef void(* GNCEngineEventHandler)(GUID *entity, QofIdType type, GNCEngineEventType event_type, gpointer user_data)

GNCEngineEventHandler Handler invoked when an engine event occurs. Parameters: entity,:  GUID of entity generating event type,:  QofIdType of the entity generating the event event_type,:  one of the single-bit GNCEngineEventTypes, not a combination user_data,:  user_data supplied when handler was registered. Definition at line 62 of file gnc-event.h.

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Function Documentation

void gnc_engine_gen_event (  QofEntity *  entity, GNCEngineEventType  event_type )

gnc_engine_generate_event Invoke all registered event handlers using the given arguments. GNC_EVENT_CREATE events should be generated after the object has been created and registered in the engine entity table. GNC_EVENT_MODIFY events should be generated whenever any data member or submember (i.e., splits) is changed. GNC_EVENT_DESTROY events should be called before the object has been destroyed or removed from the entity table. Parameters: entity,:  the GUID of the entity generating the event event_type,:  the type of event -- this should be one of the single-bit GNCEngineEventType values, not a combination. Definition at line 199 of file gnc-event.c. { if (!entity) return; if (suspend_counter) return; gnc_engine_generate_event_internal (entity, event_type); }

gint gnc_engine_register_event_handler (  GNCEngineEventHandler  handler, gpointer  user_data )

gnc_engine_register_event_handler Register a handler for engine events. Parameters: handler,:  handler to register user_data,:  data provided when handler is invoked Returns: id identifying handler Definition at line 50 of file gnc-event.c. { HandlerInfo *hi; gint handler_id; GList *node; ENTER ("(handler=%p, data=%p)", handler, user_data); /* sanity check */ if (!handler) { PERR ("no handler specified"); return 0; } /* look for a free handler id */ handler_id = next_handler_id; node = handlers; while (node) { hi = node->data; if (hi->handler_id == handler_id) { handler_id++; node = handlers; continue; } node = node->next; } /* Found one, add the handler */ hi = g_new0 (HandlerInfo, 1); hi->handler = handler; hi->user_data = user_data; hi->handler_id = handler_id; handlers = g_list_prepend (handlers, hi); /* Update id for next registration */ next_handler_id = handler_id + 1; LEAVE ("(handler=%p, data=%p) handler_id=%d", handler, user_data, handler_id); return handler_id; }

void gnc_engine_resume_events (  void   )

gnc_engine_resume_events Resume engine event generation. Definition at line 140 of file gnc-event.c. { if (suspend_counter == 0) { PERR ("suspend counter underflow"); return; } suspend_counter--; }

void gnc_engine_suspend_events (  void   )

gnc_engine_suspend_events Suspend all engine events. This function may be called multiple times. To resume event generation, an equal number of calls to gnc_engine_resume_events must be made. Definition at line 129 of file gnc-event.c. { suspend_counter++; if (suspend_counter == 0) { PERR ("suspend counter overflow"); } }

void gnc_engine_unregister_event_handler (  gint  handler_id  )

gnc_engine_unregister_event_handler Unregister an engine event handler. Parameters: handler_id,:  the id of the handler to unregister Definition at line 100 of file gnc-event.c. { GList *node; ENTER ("(handler_id=%d)", handler_id); for (node = handlers; node; node = node->next) { HandlerInfo *hi = node->data; if (hi->handler_id != handler_id) continue; /* Found it, take out of list */ handlers = g_list_remove_link (handlers, node); LEAVE ("(handler_id=%d) handler=%p data=%p", handler_id, hi->handler, hi->user_data); /* safety */ hi->handler = NULL; g_list_free_1 (node); g_free (hi); return; } PERR ("no such handler: %d", handler_id); }

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