summaryrefslogtreecommitdiffstats
path: root/src/libudev/libudev.c
blob: 73574874ca7af835e0322193e3adf9ab7ce7f7cb (plain)
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
/* SPDX-License-Identifier: LGPL-2.1-or-later */

#include <ctype.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>

#include "libudev.h"

#include "alloc-util.h"
#include "fd-util.h"
#include "string-util.h"

/**
 * SECTION:libudev
 * @short_description: libudev context
 */

/**
 * udev:
 *
 * Opaque object representing the library context.
 */
struct udev {
        unsigned n_ref;
        void *userdata;
};

/**
 * udev_get_userdata:
 * @udev: udev library context
 *
 * Retrieve stored data pointer from library context. This might be useful
 * to access from callbacks.
 *
 * Returns: stored userdata
 **/
_public_ void *udev_get_userdata(struct udev *udev) {
        assert_return(udev, NULL);

        return udev->userdata;
}

/**
 * udev_set_userdata:
 * @udev: udev library context
 * @userdata: data pointer
 *
 * Store custom @userdata in the library context.
 **/
_public_ void udev_set_userdata(struct udev *udev, void *userdata) {
        if (!udev)
                return;

        udev->userdata = userdata;
}

/**
 * udev_new:
 *
 * Create udev library context. This only allocates the basic data structure.
 *
 * The initial refcount is 1, and needs to be decremented to
 * release the resources of the udev library context.
 *
 * Returns: a new udev library context
 **/
_public_ struct udev *udev_new(void) {
        struct udev *udev;

        udev = new(struct udev, 1);
        if (!udev)
                return_with_errno(NULL, ENOMEM);

        *udev = (struct udev) {
                .n_ref = 1,
        };

        return udev;
}

/**
 * udev_ref:
 * @udev: udev library context
 *
 * Take a reference of the udev library context.
 *
 * Returns: the passed udev library context
 **/
DEFINE_PUBLIC_TRIVIAL_REF_FUNC(struct udev, udev);

/**
 * udev_unref:
 * @udev: udev library context
 *
 * Drop a reference of the udev library context. If the refcount
 * reaches zero, the resources of the context will be released.
 *
 * Returns: the passed udev library context if it has still an active reference, or #NULL otherwise.
 **/
_public_ struct udev *udev_unref(struct udev *udev) {
        if (!udev)
                return NULL;

        assert(udev->n_ref > 0);
        udev->n_ref--;
        if (udev->n_ref > 0)
                /* This is different from our convention, but let's keep backward
                 * compatibility. So, do not use DEFINE_PUBLIC_TRIVIAL_UNREF_FUNC()
                 * macro to define this function. */
                return udev;

        return mfree(udev);
}

/**
 * udev_set_log_fn:
 * @udev: udev library context
 * @log_fn: function to be called for log messages
 *
 * This function is deprecated.
 *
 **/
_public_ void udev_set_log_fn(
                        struct udev *udev,
                        void (*log_fn)(struct udev *udev,
                                       int priority, const char *file, int line, const char *fn,
                                       const char *format, va_list args)) {
        return;
}

/**
 * udev_get_log_priority:
 * @udev: udev library context
 *
 * This function is deprecated.
 *
 **/
_public_ int udev_get_log_priority(struct udev *udev) {
        return log_get_max_level();
}

/**
 * udev_set_log_priority:
 * @udev: udev library context
 * @priority: the new log priority
 *
 * This function is deprecated.
 *
 **/
_public_ void udev_set_log_priority(struct udev *udev, int priority) {
        log_set_max_level(priority);
}