1 /*
2 * GStreamer
3 * Copyright (C) 2010 Intel Corporation.
4 * Copyright (C) 2012 Matthew Waters <ystreet00@gmail.com>
5 * Copyright (C) 2016 Matthew Waters <matthew@centricular.com>
6 *
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.
11 *
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.
16 *
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., 51 Franklin St, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
21 *
22 * Authors:
23 * Matthew Allum
24 * Robert Bragg
25 * Kristian Høgsberg
26 */
27
28 /* code originally from clutter's wayland backend found here
29 * http://git.gnome.org/browse/clutter/tree/clutter/wayland/clutter-event-wayland.c
30 */
31
32 #ifdef HAVE_CONFIG_H
33 #include "config.h"
34 #endif
35
36 #include <stdint.h>
37 #include <stdlib.h>
38 #include <wayland-client.h>
39
40 #include "wayland_event_source.h"
41
42 static void
sync_callback(void * data,struct wl_callback * callback,uint32_t serial)43 sync_callback (void *data, struct wl_callback *callback, uint32_t serial)
44 {
45 gboolean *done = data;
46
47 *done = TRUE;
48 wl_callback_destroy (callback);
49 }
50
51 static const struct wl_callback_listener sync_listener = {
52 sync_callback
53 };
54
55 /* only thread safe iff called on the same thread @queue is being dispatched on */
56 gint
gst_vulkan_wl_display_roundtrip_queue(struct wl_display * display,struct wl_event_queue * queue)57 gst_vulkan_wl_display_roundtrip_queue (struct wl_display *display,
58 struct wl_event_queue *queue)
59 {
60 struct wl_callback *callback;
61 gboolean done = FALSE;
62 gint ret = 0;
63
64 if (queue) {
65 /* creating a wl_proxy and setting the queue is racy with the dispatching
66 * of the default queue */
67 while (wl_display_prepare_read_queue (display, queue) != 0) {
68 if ((ret = wl_display_dispatch_queue_pending (display, queue)) < 0)
69 return ret;
70 }
71 }
72 if (!(callback = wl_display_sync (display))) {
73 return -1;
74 }
75 wl_callback_add_listener (callback, &sync_listener, &done);
76 if (queue) {
77 wl_proxy_set_queue ((struct wl_proxy *) callback, queue);
78 wl_display_cancel_read (display);
79 while (!done && ret >= 0)
80 ret = wl_display_dispatch_queue (display, queue);
81 } else {
82 while (!done && ret >= 0)
83 ret = wl_display_dispatch (display);
84 }
85
86 if (ret == -1 && !done)
87 wl_callback_destroy (callback);
88
89 return ret;
90 }
91
92 typedef struct _WaylandEventSource
93 {
94 GSource source;
95 GPollFD pfd;
96 uint32_t mask;
97 struct wl_display *display;
98 struct wl_event_queue *queue;
99 gboolean reading;
100 } WaylandEventSource;
101
102 static gboolean
wayland_event_source_prepare(GSource * base,gint * timeout)103 wayland_event_source_prepare (GSource * base, gint * timeout)
104 {
105 WaylandEventSource *source = (WaylandEventSource *) base;
106
107 *timeout = -1;
108
109 /* we may be called multiple times for prepare */
110 if (source->reading)
111 wl_display_cancel_read (source->display);
112
113 if (source->queue) {
114 while (wl_display_prepare_read_queue (source->display, source->queue) != 0) {
115 if (wl_display_dispatch_queue_pending (source->display,
116 source->queue) < 0) {
117 g_critical ("Failed to dispatch pending events\n");
118 }
119 }
120 } else {
121 while (wl_display_prepare_read (source->display) != 0) {
122 if (wl_display_dispatch_pending (source->display) < 0) {
123 g_critical ("Failed to dispatch pending events\n");
124 }
125 }
126 }
127 source->reading = TRUE;
128
129 /* FIXME: this may return EAGAIN if the fd is full */
130 if (wl_display_flush (source->display) < 0)
131 g_critical ("Failed to flush Wayland connection\n");
132
133 return FALSE;
134 }
135
136 static gboolean
wayland_event_source_check(GSource * base)137 wayland_event_source_check (GSource * base)
138 {
139 WaylandEventSource *source = (WaylandEventSource *) base;
140 gboolean retval;
141
142 retval = source->pfd.revents;
143
144 if (source->pfd.revents & G_IO_IN) {
145 wl_display_read_events (source->display);
146 } else {
147 wl_display_cancel_read (source->display);
148 }
149 source->reading = FALSE;
150
151 return retval;
152 }
153
154 static gboolean
wayland_event_source_dispatch(GSource * base,GSourceFunc callback,gpointer data)155 wayland_event_source_dispatch (GSource * base,
156 GSourceFunc callback, gpointer data)
157 {
158 WaylandEventSource *source = (WaylandEventSource *) base;
159
160 if (source->queue)
161 wl_display_dispatch_queue_pending (source->display, source->queue);
162 else
163 wl_display_dispatch_pending (source->display);
164 source->pfd.revents = 0;
165
166 if (callback)
167 callback (data);
168
169 return TRUE;
170 }
171
172 static void
wayland_event_source_finalize(GSource * base)173 wayland_event_source_finalize (GSource * base)
174 {
175 WaylandEventSource *source = (WaylandEventSource *) base;
176
177 if (source->reading) {
178 wl_display_cancel_read (source->display);
179 }
180 source->reading = FALSE;
181 }
182
183 static GSourceFuncs wayland_event_source_funcs = {
184 wayland_event_source_prepare,
185 wayland_event_source_check,
186 wayland_event_source_dispatch,
187 wayland_event_source_finalize
188 };
189
190 GSource *
wayland_event_source_new(struct wl_display * display,struct wl_event_queue * queue)191 wayland_event_source_new (struct wl_display *display,
192 struct wl_event_queue *queue)
193 {
194 WaylandEventSource *source;
195
196 source = (WaylandEventSource *)
197 g_source_new (&wayland_event_source_funcs, sizeof (WaylandEventSource));
198 source->display = display;
199 source->queue = queue;
200 source->pfd.fd = wl_display_get_fd (display);
201 source->pfd.events = G_IO_IN | G_IO_ERR;
202 g_source_add_poll (&source->source, &source->pfd);
203
204 return &source->source;
205 }
206