1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
* Copyright (C) 2018-2019, Google Inc.
*
* device_enumerator_udev.cpp - udev-based device enumerator
*/
#include "device_enumerator_udev.h"
#include <fcntl.h>
#include <libudev.h>
#include <string.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <libcamera/event_notifier.h>
#include "log.h"
namespace libcamera {
LOG_DECLARE_CATEGORY(DeviceEnumerator)
DeviceEnumeratorUdev::DeviceEnumeratorUdev()
: udev_(nullptr)
{
}
DeviceEnumeratorUdev::~DeviceEnumeratorUdev()
{
delete notifier_;
if (monitor_)
udev_monitor_unref(monitor_);
if (udev_)
udev_unref(udev_);
}
int DeviceEnumeratorUdev::init()
{
int ret;
if (udev_)
return -EBUSY;
udev_ = udev_new();
if (!udev_)
return -ENODEV;
monitor_ = udev_monitor_new_from_netlink(udev_, "udev");
if (!monitor_)
return -ENODEV;
ret = udev_monitor_filter_add_match_subsystem_devtype(monitor_, "media",
nullptr);
if (ret < 0)
return ret;
return 0;
}
int DeviceEnumeratorUdev::enumerate()
{
struct udev_enumerate *udev_enum = nullptr;
struct udev_list_entry *ents, *ent;
int ret;
udev_enum = udev_enumerate_new(udev_);
if (!udev_enum)
return -ENOMEM;
ret = udev_enumerate_add_match_subsystem(udev_enum, "media");
if (ret < 0)
goto done;
ret = udev_enumerate_scan_devices(udev_enum);
if (ret < 0)
goto done;
ents = udev_enumerate_get_list_entry(udev_enum);
if (!ents)
goto done;
udev_list_entry_foreach(ent, ents) {
struct udev_device *dev;
const char *devnode;
const char *syspath = udev_list_entry_get_name(ent);
dev = udev_device_new_from_syspath(udev_, syspath);
if (!dev) {
LOG(DeviceEnumerator, Warning)
<< "Failed to get device for '"
<< syspath << "', skipping";
continue;
}
devnode = udev_device_get_devnode(dev);
if (!devnode) {
udev_device_unref(dev);
ret = -ENODEV;
goto done;
}
addDevice(devnode);
udev_device_unref(dev);
}
done:
udev_enumerate_unref(udev_enum);
if (ret < 0)
return ret;
ret = udev_monitor_enable_receiving(monitor_);
if (ret < 0)
return ret;
int fd = udev_monitor_get_fd(monitor_);
notifier_ = new EventNotifier(fd, EventNotifier::Read);
notifier_->activated.connect(this, &DeviceEnumeratorUdev::udevNotify);
return 0;
}
std::string DeviceEnumeratorUdev::lookupDeviceNode(int major, int minor)
{
struct udev_device *device;
const char *name;
dev_t devnum;
std::string deviceNode = std::string();
devnum = makedev(major, minor);
device = udev_device_new_from_devnum(udev_, 'c', devnum);
if (!device)
return std::string();
name = udev_device_get_devnode(device);
if (name)
deviceNode = name;
udev_device_unref(device);
return deviceNode;
}
void DeviceEnumeratorUdev::udevNotify(EventNotifier *notifier)
{
struct udev_device *dev = udev_monitor_receive_device(monitor_);
std::string action(udev_device_get_action(dev));
std::string deviceNode(udev_device_get_devnode(dev));
LOG(DeviceEnumerator, Debug)
<< action << " device " << udev_device_get_devnode(dev);
if (action == "add") {
addDevice(deviceNode);
} else if (action == "remove") {
removeDevice(deviceNode);
}
udev_device_unref(dev);
}
} /* namespace libcamera */
|
