2 * AT-SPI - Assistive Technology Service Provider Interface
3 * (Gnome Accessibility Project; http://developer.gnome.org/projects/gap)
5 * Copyright 2009, 2010 Codethink Ltd.
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
27 #include "accessible-leasing.h"
30 #include "accessible-cache.h"
33 /*---------------------------------------------------------------------------*/
35 SpiLeasing *spi_global_leasing;
37 typedef struct _ExpiryElement
43 static void spi_leasing_dispose (GObject * object);
45 static void spi_leasing_finalize (GObject * object);
47 static void add_expiry_timeout (SpiLeasing * leasing);
49 /*---------------------------------------------------------------------------*/
51 G_DEFINE_TYPE (SpiLeasing, spi_leasing, G_TYPE_OBJECT)
53 static void spi_leasing_class_init (SpiLeasingClass * klass)
55 GObjectClass *object_class = (GObjectClass *) klass;
57 spi_leasing_parent_class = g_type_class_ref (G_TYPE_OBJECT);
59 object_class->finalize = spi_leasing_finalize;
60 object_class->dispose = spi_leasing_dispose;
64 spi_leasing_init (SpiLeasing * leasing)
66 leasing->expiry_queue = g_queue_new ();
67 leasing->expiry_func_id = 0;
71 spi_leasing_finalize (GObject * object)
73 SpiLeasing *leasing = SPI_LEASING (object);
75 g_free (leasing->expiry_queue);
76 G_OBJECT_CLASS (spi_leasing_parent_class)->finalize (object);
80 spi_leasing_dispose (GObject * object)
82 SpiLeasing *leasing = SPI_LEASING (object);
85 while (head = g_queue_pop_head (leasing->expiry_queue))
87 g_object_unref (head->object);
88 g_slice_free (ExpiryElement, head);
90 G_OBJECT_CLASS (spi_leasing_parent_class)->dispose (object);
93 /*---------------------------------------------------------------------------*/
96 End the lease on all objects whose expiry time has passed.
98 Check when the next event is and set the next expiry func.
101 expiry_func (gpointer data)
103 SpiLeasing *leasing = SPI_LEASING (data);
105 ExpiryElement *head, *current;
108 g_get_current_time (&t);
110 head = g_queue_peek_head (leasing->expiry_queue);
111 while (head != NULL && head->expiry_s <= t.tv_sec)
113 current = g_queue_pop_head (leasing->expiry_queue);
116 g_debug ("REVOKE - ");
117 spi_cache_print_info (current->object);
120 g_object_unref (current->object);
121 g_slice_free (ExpiryElement, current);
123 head = g_queue_peek_head (leasing->expiry_queue);
126 leasing->expiry_func_id = 0;
127 add_expiry_timeout (leasing);
132 /*---------------------------------------------------------------------------*/
135 Checks if an expiry timeout is already scheduled, if so returns.
136 This is becasue events will always be added to the end of the queue.
137 Events are always later in time to previoulsy added events.
139 Otherwise calculate the next wake time using the top of the queue
140 and add the next expiry function.
142 This function is called when a lease is added or at the end of the
143 expiry function to add the next expiry timeout.
146 add_expiry_timeout (SpiLeasing * leasing)
152 if (leasing->expiry_func_id != 0)
155 elem = (ExpiryElement *) g_queue_peek_head (leasing->expiry_queue);
159 /* The current time is implicitly rounded down here by ignoring the us */
160 g_get_current_time (&t);
161 next_expiry = elem->expiry_s - t.tv_sec;
162 leasing->expiry_func_id = g_timeout_add_seconds (next_expiry,
163 expiry_func, leasing);
166 /*---------------------------------------------------------------------------*/
169 The lease time is expected to be in seconds, the rounding is going to be to
170 intervals of 1 second.
172 The lease time is going to be rounded up, as the lease time should be
173 considered a MINIMUM that the object will be leased for.
175 #define LEASE_TIME_S 15
176 #define EXPIRY_TIME_S (LEASE_TIME_S + 1)
179 spi_leasing_take (SpiLeasing * leasing, GObject * object)
182 Get the current time.
184 Add the release event to the queue.
185 Check the next expiry.
193 g_get_current_time (&t);
194 expiry_s = t.tv_sec + EXPIRY_TIME_S;
196 elem = g_slice_new (ExpiryElement);
197 elem->expiry_s = expiry_s;
198 elem->object = g_object_ref (object);
200 g_queue_push_tail (leasing->expiry_queue, elem);
202 add_expiry_timeout (leasing);
205 g_debug ("LEASE - ");
206 spi_cache_print_info (object);
212 /*END------------------------------------------------------------------------*/