/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
*
* Authors: Michel Zucchi <notzed@ximian.com>
*
* Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
/*
This a bit 'whipped together', so is likely to change mid-term
*/
#ifndef __E_EVENT_H__
#define __E_EVENT_H__
#include <glib-object.h>
#ifdef __cplusplus
extern "C" {
#pragma }
#endif /* __cplusplus */
/* This is an abstract event management class. */
typedef struct _EEvent EEvent;
typedef struct _EEventClass EEventClass;
typedef struct _EEventItem EEventItem;
typedef struct _EEventFactory EEventFactory; /* anonymous type */
typedef struct _EEventTarget EEventTarget;
typedef void (*EEventItemsFunc)(EEvent *ee, GSList *items, void *data);
typedef void (*EEventFunc)(EEvent *ee, EEventItem *item, void *data);
typedef void (*EEventFactoryFunc)(EEvent *ee, void *);
/**
* enum _e_event_t - Event type.
*
* @E_EVENT_PASS: A passthrough event handler which only receives the event.
* @E_EVENT_SINK: A sink event handler swallows all events it processes.
*
* The event type defines what type of event listener this is.
*
* Events should normally be @E_EVENT_PASS.
**/
enum _e_event_t {
E_EVENT_PASS, /* passthrough */
E_EVENT_SINK, /* sink events */
};
/**
* struct _EEventItem - An event listener item.
*
* @type: The type of the event listener.
* @priority: A signed number signifying the priority of the event
* listener. 0 should be used normally. This is used to order event
* receipt when multiple listners are present.
* @id: The name of the event to listen to. By convention events are of the form
* "component.subcomponent". The target mask provides further
* sub-event type qualification.
* @target_type: Target type for this event. This is implementation
* specific.
* @handle: Event handler callback.
* @user_data: Callback data.
* @enable: Target-specific mask to qualify the receipt of events.
* This is target and implementation specific.
*
* An EEventItem defines a specific event listening point on a given
* EEvent object. When an event is broadcast onto an EEvent handler,
* any matching EEventItems will be invoked in priority order.
**/
struct _EEventItem {
enum _e_event_t type;
int priority; /* priority of event */
const char *id; /* event id */
int target_type;
EEventFunc handle;
void *user_data;
guint32 enable; /* enable mask */
};
/**
* struct _EEventTarget - Base EventTarget.
*
* @event: Parent object.
* @type: Target type. Defined by the implementation.
* @mask: Mask of this target. This is defined by the implementation,
* the type, and the actual content of the target.
*
* This defined a base EventTarget. This must be subclassed by
* implementations to provide contextual data for events, and define
* the enablement qualifiers.
*
**/
struct _EEventTarget {
struct _EEvent *event; /* used for virtual methods */
guint32 type; /* targe type, for implementors */
guint32 mask; /* depends on type, enable mask */
/* implementation fields follow */
};
/**
* struct _EEvent - An Event Manager.
*
* @object: Superclass.
* @priv: Private data.
* @id: Id of this event manager.
* @target: The current target, only set during event emission.
*
* The EEvent manager object. Each component which defines event
* types supplies a single EEvent manager object. This manager routes
* all events invoked on this object to all registered listeners based
* on their qualifiers.
**/
struct _EEvent {
GObject object;
struct _EEventPrivate *priv;
char *id;
EEventTarget *target; /* current target during event emission */
};
/**
* struct _EEventClass - Event management type.
*
* @object_class: Superclass.
* @target_free: Virtual method to free the target.
*
* The EEvent class definition. This must be sub-classed for each
* component that wishes to provide hookable events. The subclass
* only needs to know how to allocate and free each target type it
* supports.
**/
struct _EEventClass {
GObjectClass object_class;
void (*target_free)(EEvent *ep, EEventTarget *t);
};
GType e_event_get_type(void);
EEvent *e_event_construct(EEvent *, const char *id);
void *e_event_add_items(EEvent *emp, GSList *items, EEventItemsFunc freefunc, void *data);
void e_event_remove_items(EEvent *emp, void *handle);
void e_event_emit(EEvent *, const char *id, EEventTarget *);
void *e_event_target_new(EEvent *, int type, size_t size);
void e_event_target_free(EEvent *, void *);
/* ********************************************************************** */
/* event plugin target, they are closely integrated */
/* To implement a basic event menu plugin, you just need to subclass
this and initialise the class target type tables */
/* For events, the plugin item talks to a specific instance, rather than
a set of instances of the hook handler */
#include "e-util/e-plugin.h"
typedef struct _EEventHook EEventHook;
typedef struct _EEventHookClass EEventHookClass;
typedef struct _EPluginHookTargetMap EEventHookTargetMap;
typedef struct _EPluginHookTargetKey EEventHookTargetMask;
typedef void (*EEventHookFunc)(struct _EPlugin *plugin, EEventTarget *target);
/**
* struct _EEventHook - An event hook.
*
* @hook: Superclass.
*
* The EEventHook class loads and manages the meta-data required to
* track event listeners. Unlike other hook types, there is a 1:1
* match between an EEventHook instance class and its EEvent instance.
*
* When the hook is loaded, all of its event hooks are stored directly
* on the corresponding EEvent which is stored in its class static area.
**/
struct _EEventHook {
EPluginHook hook;
};
/**
* struct _EEventHookClass -
*
* @hook_class:
* @target_map: Table of EPluginHookTargetMaps which enumerate the
* target types and enable bits of the implementing class.
* @event: The EEvent instance on which all loaded events must be registered.
*
* The EEventHookClass is an empty event hooking class, which must be
* subclassed and initialised before use.
*
* The EPluginHookClass.id must be set to the name and version of the
* hook handler itself, and then the type must be registered with the
* EPlugin hook list before any plugins are loaded.
**/
struct _EEventHookClass {
EPluginHookClass hook_class;
/* EEventHookTargetMap by .type */
GHashTable *target_map;
/* the event router these events's belong to */
EEvent *event;
};
GType e_event_hook_get_type(void);
/* for implementors */
void e_event_hook_class_add_target_map(EEventHookClass *klass, const EEventHookTargetMap *);
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif /* __E_EVENT_H__ */
