2 * Copyright (c) 2017-2019, 2021 Arm Limited.
4 * SPDX-License-Identifier: MIT
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in all
14 * copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
25 #include "swapchain_wl_helpers.hpp"
27 #include <wayland-client.h>
28 #include <linux-dmabuf-unstable-v1-client-protocol.h>
36 void registry_handler(void *data, struct wl_registry *wl_registry, uint32_t name, const char *interface,
39 zwp_linux_dmabuf_v1 **dmabuf_interface = (zwp_linux_dmabuf_v1 **)data;
41 if (!strcmp(interface, "zwp_linux_dmabuf_v1"))
44 (zwp_linux_dmabuf_v1 *)wl_registry_bind(wl_registry, name, &zwp_linux_dmabuf_v1_interface, version);
45 assert(*dmabuf_interface);
49 int dispatch_queue(struct wl_display *display, struct wl_event_queue *queue, int timeout)
52 struct pollfd pfd = {};
55 /* Before we sleep, dispatch any pending events. prepare_read_queue will return 0 whilst there are pending
56 * events to dispatch on the queue. */
57 while (0 != wl_display_prepare_read_queue(display, queue))
59 /* dispatch_queue_pending returns -1 on error, or the number of events dispatched otherwise. If we
60 * already dispatched some events, then we might not need to sleep, as we might have just dispatched
61 * the event we want, so return immediately. */
62 err = wl_display_dispatch_queue_pending(display, queue);
65 return (0 > err) ? -1 : 1;
69 /* wl_display_read_events performs a non-blocking read. */
70 pfd.fd = wl_display_get_fd(display);
74 /* Timeout is given in milliseconds. A return value of 0, or -1 with errno set to EINTR means that we
75 * should retry as the timeout was exceeded or we were interrupted by a signal, respectively. A
76 * return value of 1 means that something happened, and we should inspect the pollfd structure to see
79 err = poll(&pfd, 1, timeout);
83 wl_display_cancel_read(display);
90 /* Interrupted by a signal; restart. This resets the timeout. */
95 /* Something else bad happened; abort. */
96 wl_display_cancel_read(display);
102 if (POLLIN == pfd.revents)
104 /* We have data to read, and no errors; proceed to read_events. */
109 /* An error occurred, e.g. file descriptor was closed from underneath us. */
110 wl_display_cancel_read(display);
116 /* Actually read the events from the display. A failure in read_events calls cancel_read internally for us,
117 * so we don't need to do that here. */
118 err = wl_display_read_events(display);
124 /* Finally, if we read any events relevant to our queue, we can dispatch them. */
125 err = wl_display_dispatch_queue_pending(display, queue);
126 retval = err < 0 ? -1 : 1;