1 /*
2  * Copyright (c) 2023 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef LIBUDEV_H
17 #define LIBUDEV_H
18 
19 #pragma once
20 
21 #include <stdarg.h>
22 #include <sys/sysmacros.h>
23 #include <sys/types.h>
24 #include <sys/stat.h>
25 
26 #ifdef __cplusplus
27 extern "C" {
28 #endif // __cplusplus
29 
30 /**
31  * udev - library context
32  *
33  * reads the udev config and system environment
34  * allows custom logging
35  */
36 struct udev;
37 struct udev *udev_ref(struct udev *udev);
38 struct udev *udev_unref(struct udev *udev);
39 struct udev *udev_new(void);
40 void udev_set_log_fn(struct udev *udev, void (*log_fn)(struct udev *udev, int priority, const char *file, int line,
41                                             const char *fn, const char *format, va_list args))
42     __attribute__((deprecated));
43 int udev_get_log_priority(struct udev *udev) __attribute__((deprecated));
44 void udev_set_log_priority(struct udev *udev, int priority) __attribute__((deprecated));
45 void *udev_get_userdata(struct udev *udev);
46 void udev_set_userdata(struct udev *udev, void *userdata);
47 
48 /**
49  * udev_list access to libudev generated lists
50  */
51 struct udev_list_entry;
52 struct udev_list_entry *udev_list_entry_get_next(struct udev_list_entry *list_entry);
53 struct udev_list_entry *udev_list_entry_get_by_name(struct udev_list_entry *list_entry, const char *name);
54 const char *udev_list_entry_get_name(struct udev_list_entry *list_entry);
55 const char *udev_list_entry_get_value(struct udev_list_entry *list_entry);
56 
57 /**
58  * udev_list_entry_foreach:
59  * @list_entry: entry to store the current position
60  * @first_entry: first entry to start with
61  *
62  * Helper to iterate over all entries of a list.
63  */
64 #define udev_list_entry_foreach(list_entry, first_entry) \
65     for (list_entry = first_entry; list_entry != NULL; list_entry = udev_list_entry_get_next(list_entry))
66 
67 /**
68  * udev_device access to sysfs/kernel devices
69  */
70 struct udev_device;
71 struct udev_device *udev_device_ref(struct udev_device *udev_device);
72 struct udev_device *udev_device_unref(struct udev_device *udev_device);
73 struct udev *udev_device_get_udev(struct udev_device *udev_device);
74 struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *syspath);
75 struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, dev_t devnum);
76 struct udev_device *udev_device_new_from_subsystem_sysname(
77     struct udev *udev, const char *subsystem, const char *sysname);
78 struct udev_device *udev_device_new_from_device_id(struct udev *udev, const char *id);
79 struct udev_device *udev_device_new_from_environment(struct udev *udev);
80 
81 /**
82  * udev_device_get_parent_*() does not take a reference on the returned device, it is automatically unref'd with the
83  * parent
84  */
85 struct udev_device *udev_device_get_parent(struct udev_device *udev_device);
86 struct udev_device *udev_device_get_parent_with_subsystem_devtype(
87     struct udev_device *udev_device, const char *subsystem, const char *devtype);
88 
89 /* retrieve device properties */
90 int udev_device_read_db(struct udev_device *udev_device);
91 const char *udev_device_get_devpath(struct udev_device *udev_device);
92 const char *udev_device_get_subsystem(struct udev_device *udev_device);
93 const char *udev_device_get_devtype(struct udev_device *udev_device);
94 const char *udev_device_get_syspath(struct udev_device *udev_device);
95 const char *udev_device_get_sysname(struct udev_device *udev_device);
96 const char *udev_device_get_sysnum(struct udev_device *udev_device);
97 const char *udev_device_get_devnode(struct udev_device *udev_device);
98 int udev_device_get_is_initialized(struct udev_device *udev_device);
99 struct udev_list_entry *udev_device_get_devlinks_list_entry(struct udev_device *udev_device);
100 struct udev_list_entry *udev_device_get_properties_list_entry(struct udev_device *udev_device);
101 struct udev_list_entry *udev_device_get_tags_list_entry(struct udev_device *udev_device);
102 struct udev_list_entry *udev_device_get_sysattr_list_entry(struct udev_device *udev_device);
103 const char *udev_device_get_property_value(struct udev_device *udev_device, const char *key);
104 const char *udev_device_get_driver(struct udev_device *udev_device);
105 dev_t udev_device_get_devnum(struct udev_device *udev_device);
106 const char *udev_device_get_action(struct udev_device *udev_device);
107 unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device);
108 unsigned long long int udev_device_get_usec_since_initialized(struct udev_device *udev_device);
109 const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const char *sysattr);
110 int udev_device_set_sysattr_value(struct udev_device *udev_device, const char *sysattr, char *value);
111 int udev_device_has_tag(struct udev_device *udev_device, const char *tag);
112 
113 /**
114  * udev_monitor access to kernel uevents and udev events
115  */
116 struct udev_monitor;
117 struct udev_monitor *udev_monitor_ref(struct udev_monitor *udev_monitor);
118 struct udev_monitor *udev_monitor_unref(struct udev_monitor *udev_monitor);
119 struct udev *udev_monitor_get_udev(struct udev_monitor *udev_monitor);
120 /* kernel and udev generated events over netlink */
121 struct udev_monitor *udev_monitor_new_from_netlink(struct udev *udev, const char *name);
122 /* bind socket */
123 int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor);
124 int udev_monitor_set_receive_buffer_size(struct udev_monitor *udev_monitor, int size);
125 int udev_monitor_get_fd(struct udev_monitor *udev_monitor);
126 struct udev_device *udev_monitor_receive_device(struct udev_monitor *udev_monitor);
127 /* in-kernel socket filters to select messages that get delivered to a listener */
128 int udev_monitor_filter_add_match_subsystem_devtype(
129     struct udev_monitor *udev_monitor, const char *subsystem, const char *devtype);
130 int udev_monitor_filter_add_match_tag(struct udev_monitor *udev_monitor, const char *tag);
131 int udev_monitor_filter_update(struct udev_monitor *udev_monitor);
132 int udev_monitor_filter_remove(struct udev_monitor *udev_monitor);
133 
134 /**
135  * udev_enumerate search sysfs for specific devices and provide a sorted list
136  */
137 struct udev_enumerate;
138 struct udev_enumerate *udev_enumerate_ref(struct udev_enumerate *udev_enumerate);
139 struct udev_enumerate *udev_enumerate_unref(struct udev_enumerate *udev_enumerate);
140 struct udev *udev_enumerate_get_udev(struct udev_enumerate *udev_enumerate);
141 struct udev_enumerate *udev_enumerate_new(struct udev *udev);
142 /* device properties filter */
143 int udev_enumerate_add_match_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem);
144 int udev_enumerate_add_nomatch_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem);
145 int udev_enumerate_add_match_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value);
146 int udev_enumerate_add_nomatch_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value);
147 int udev_enumerate_add_match_property(struct udev_enumerate *udev_enumerate, const char *property, const char *value);
148 int udev_enumerate_add_match_sysname(struct udev_enumerate *udev_enumerate, const char *sysname);
149 int udev_enumerate_add_match_tag(struct udev_enumerate *udev_enumerate, const char *tag);
150 int udev_enumerate_add_match_parent(struct udev_enumerate *udev_enumerate, struct udev_device *parent);
151 int udev_enumerate_add_match_is_initialized(struct udev_enumerate *udev_enumerate);
152 int udev_enumerate_add_syspath(struct udev_enumerate *udev_enumerate, const char *syspath);
153 /* run enumeration with active filters */
154 int udev_enumerate_scan_devices(struct udev_enumerate *udev_enumerate);
155 int udev_enumerate_scan_subsystems(struct udev_enumerate *udev_enumerate);
156 /* return device list */
157 struct udev_list_entry *udev_enumerate_get_list_entry(struct udev_enumerate *udev_enumerate);
158 
159 /**
160  * udev_queue access to the currently running udev events
161  */
162 struct udev_queue;
163 struct udev_queue *udev_queue_ref(struct udev_queue *udev_queue);
164 struct udev_queue *udev_queue_unref(struct udev_queue *udev_queue);
165 struct udev *udev_queue_get_udev(struct udev_queue *udev_queue);
166 struct udev_queue *udev_queue_new(struct udev *udev);
167 unsigned long long int udev_queue_get_kernel_seqnum(struct udev_queue *udev_queue) __attribute__((deprecated));
168 unsigned long long int udev_queue_get_udev_seqnum(struct udev_queue *udev_queue) __attribute__((deprecated));
169 int udev_queue_get_udev_is_active(struct udev_queue *udev_queue);
170 int udev_queue_get_queue_is_empty(struct udev_queue *udev_queue);
171 int udev_queue_get_seqnum_is_finished(struct udev_queue *udev_queue, unsigned long long int seqnum)
172     __attribute__((deprecated));
173 int udev_queue_get_seqnum_sequence_is_finished(struct udev_queue *udev_queue, unsigned long long int start,
174     unsigned long long int end) __attribute__((deprecated));
175 int udev_queue_get_fd(struct udev_queue *udev_queue);
176 int udev_queue_flush(struct udev_queue *udev_queue);
177 struct udev_list_entry *udev_queue_get_queued_list_entry(struct udev_queue *udev_queue) __attribute__((deprecated));
178 
179 /**
180  * udev_hwdb access to the static hardware properties database
181  */
182 struct udev_hwdb;
183 struct udev_hwdb *udev_hwdb_new(struct udev *udev);
184 struct udev_hwdb *udev_hwdb_ref(struct udev_hwdb *hwdb);
185 struct udev_hwdb *udev_hwdb_unref(struct udev_hwdb *hwdb);
186 struct udev_list_entry *udev_hwdb_get_properties_list_entry(
187     struct udev_hwdb *hwdb, const char *modalias, unsigned int flags);
188 
189 /**
190  * udev_util udev specific utilities
191  */
192 int udev_util_encode_string(const char *str, char *str_enc, size_t len);
193 
194 #ifdef __cplusplus
195 } /* extern "C" */
196 #endif // __cplusplus
197 #endif // LIBUDEV_H