codec: hxxx_helper: make debug messages optional
[vlc.git] / lib / event.c
blob8c64cacac320703fd9f0d15645025af6ae27b02d
1 /*****************************************************************************
2 * event.c: New libvlc event control API
3 *****************************************************************************
4 * Copyright (C) 2007-2010 VLC authors and VideoLAN
5 * $Id $
7 * Authors: Filippo Carone <filippo@carone.org>
8 * Pierre d'Herbemont <pdherbemont # videolan.org>
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU Lesser General Public License as published by
12 * the Free Software Foundation; either version 2.1 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with this program; if not, write to the Free Software Foundation,
22 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23 *****************************************************************************/
25 #ifdef HAVE_CONFIG_H
26 # include "config.h"
27 #endif
29 #include <assert.h>
30 #include <errno.h>
32 #include <vlc/libvlc.h>
33 #include "libvlc_internal.h"
35 #include <vlc_common.h>
38 * Event Handling
41 /* Example usage
43 * struct libvlc_cool_object_t
44 * {
45 * ...
46 * libvlc_event_manager_t event_manager;
47 * ...
48 * }
50 * libvlc_my_cool_object_new()
51 * {
52 * ...
53 * libvlc_event_manager_init(&p_self->event_manager, p_self)
54 * ...
55 * }
57 * libvlc_my_cool_object_release()
58 * {
59 * ...
60 * libvlc_event_manager_release(&p_self->event_manager);
61 * ...
62 * }
64 * libvlc_my_cool_object_do_something()
65 * {
66 * ...
67 * libvlc_event_t event;
68 * event.type = libvlc_MyCoolObjectDidSomething;
69 * event.u.my_cool_object_did_something.what_it_did = kSomething;
70 * libvlc_event_send(&p_self->event_manager, &event);
71 * }
72 * */
74 typedef struct libvlc_event_listener_t
76 libvlc_event_type_t event_type;
77 void * p_user_data;
78 libvlc_callback_t pf_callback;
79 } libvlc_event_listener_t;
82 * Internal libvlc functions
85 void libvlc_event_manager_init(libvlc_event_manager_t *em, void *obj)
87 em->p_obj = obj;
88 vlc_array_init(&em->listeners);
89 vlc_mutex_init_recursive(&em->lock);
92 void libvlc_event_manager_destroy(libvlc_event_manager_t *em)
94 vlc_mutex_destroy(&em->lock);
96 for (size_t i = 0; i < vlc_array_count(&em->listeners); i++)
97 free(vlc_array_item_at_index(&em->listeners, i));
99 vlc_array_clear(&em->listeners);
102 /**************************************************************************
103 * libvlc_event_send (internal) :
105 * Send a callback.
106 **************************************************************************/
107 void libvlc_event_send( libvlc_event_manager_t * p_em,
108 libvlc_event_t * p_event )
110 /* Fill event with the sending object now */
111 p_event->p_obj = p_em->p_obj;
113 vlc_mutex_lock(&p_em->lock);
114 for (size_t i = 0; i < vlc_array_count(&p_em->listeners); i++)
116 libvlc_event_listener_t *listener;
118 listener = vlc_array_item_at_index(&p_em->listeners, i);
119 if (listener->event_type == p_event->type)
120 listener->pf_callback(p_event, listener->p_user_data);
122 vlc_mutex_unlock(&p_em->lock);
126 * Public libvlc functions
129 /**************************************************************************
130 * libvlc_event_attach (public) :
132 * Add a callback for an event.
133 **************************************************************************/
134 int libvlc_event_attach(libvlc_event_manager_t *em, libvlc_event_type_t type,
135 libvlc_callback_t callback, void *opaque)
137 libvlc_event_listener_t *listener = malloc(sizeof (*listener));
138 if (unlikely(listener == NULL))
139 return ENOMEM;
141 listener->event_type = type;
142 listener->p_user_data = opaque;
143 listener->pf_callback = callback;
145 int i_ret;
146 vlc_mutex_lock(&em->lock);
147 if(vlc_array_append(&em->listeners, listener) != 0)
149 i_ret = VLC_EGENERIC;
150 free(listener);
152 else
153 i_ret = VLC_SUCCESS;
154 vlc_mutex_unlock(&em->lock);
155 return i_ret;
158 /**************************************************************************
159 * libvlc_event_detach (public) :
161 * Remove a callback for an event.
162 **************************************************************************/
163 void libvlc_event_detach(libvlc_event_manager_t *em, libvlc_event_type_t type,
164 libvlc_callback_t callback, void *opaque)
166 vlc_mutex_lock(&em->lock);
167 for (size_t i = 0; i < vlc_array_count(&em->listeners); i++)
169 libvlc_event_listener_t *listener;
171 listener = vlc_array_item_at_index(&em->listeners, i);
173 if (listener->event_type == type
174 && listener->pf_callback == callback
175 && listener->p_user_data == opaque)
176 { /* that's our listener */
177 vlc_array_remove(&em->listeners, i);
178 vlc_mutex_unlock(&em->lock);
179 free(listener);
180 return;
183 abort();