tests/testdisplay_hotplug.c

/*
 * Copyright 2010 Intel Corporation
 *   Jesse Barnes <jesse.barnes@intel.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include "testdisplay.h"
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#if HAVE_UDEV
#include <libudev.h>
static struct udev_monitor *uevent_monitor;
static struct udev *udev;
static GIOChannel *udevchannel;

static gboolean hotplug_event(GIOChannel *source, GIOCondition condition,
			      gpointer data)
{
	struct udev_device *dev;
	dev_t udev_devnum;
	struct stat s;
	const char *hotplug;

	dev = udev_monitor_receive_device(uevent_monitor);
	if (!dev)
		goto out;

	udev_devnum = udev_device_get_devnum(dev);
	fstat(drm_fd, &s);

	hotplug = udev_device_get_property_value(dev, "HOTPLUG");

	if (memcmp(&s.st_rdev, &udev_devnum, sizeof(dev_t)) == 0 &&
	    hotplug && atoi(hotplug) == 1)
		update_display();

	udev_device_unref(dev);
out:
	return TRUE;
}


gboolean testdisplay_setup_hotplug(void)
{
	int ret;

	udev = udev_new();
	if (!udev) {
		fprintf(stderr, "failed to create udev object\n");
		goto out;
	}

	uevent_monitor = udev_monitor_new_from_netlink(udev, "udev");
	if (!uevent_monitor) {
		fprintf(stderr, "failed to create udev event monitor\n");
		goto out;
	}

	ret = udev_monitor_filter_add_match_subsystem_devtype(uevent_monitor,
							      "drm",
							      "drm_minor");
	if (ret < 0) {
		fprintf(stderr, "failed to filter for drm events\n");
		goto out;
	}

	ret = udev_monitor_enable_receiving(uevent_monitor);
	if (ret < 0) {
		fprintf(stderr, "failed to enable udev event reception\n");
		goto out;
	}

	udevchannel =
		g_io_channel_unix_new(udev_monitor_get_fd(uevent_monitor));
	if (!udevchannel) {
		fprintf(stderr, "failed to create udev GIO channel\n");
		goto out;
	}

	ret = g_io_add_watch(udevchannel, G_IO_IN | G_IO_ERR, hotplug_event,
			     udev);
	if (ret < 0) {
		fprintf(stderr, "failed to add watch on udev GIO channel\n");
		goto out;
	}

	return TRUE;

out:
	testdisplay_cleanup_hotplug();
	return FALSE;
}

void testdisplay_cleanup_hotplug(void)
{
	if (udevchannel)
		g_io_channel_shutdown(udevchannel, TRUE, NULL);
	if (uevent_monitor)
		udev_monitor_unref(uevent_monitor);
	if (udev)
		udev_unref(udev);
}
#else
gboolean testdisplay_setup_hotplug(void)
{
	fprintf(stderr, "no hotplug support on this platform\n");
	return TRUE;
}

void testdisplay_cleanup_hotplug(void)
{
}
#endif