summaryrefslogtreecommitdiffstats
path: root/src/fdev.c
blob: a8f369564fbd59a42616f83ce8ff46f2c15d4501 (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
155
156
157
158
159
/*
 * Copyright (C) 2018 "IoT.bzh"
 * Author José Bollo <jose.bollo@iot.bzh>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <stdint.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>

#define FDEV_PROVIDER
#include "fdev.h"

struct fdev
{
	int fd;
	uint32_t events;
	int repeat;
	unsigned refcount;
	struct fdev_itf *itf;
	void *closure_itf;
	void (*callback)(void*,uint32_t,struct fdev*);
	void *closure_callback;
};

struct fdev *fdev_create(int fd)
{
	struct fdev *fdev;

	fdev = calloc(1, sizeof *fdev);
	if (!fdev)
		errno = ENOMEM;
	else {
		fdev->fd = fd;
		fdev->refcount = 3; /* set autoclose by default */
		fdev->repeat = -1; /* always repeat by default */
	}
	return fdev;
}

void fdev_set_itf(struct fdev *fdev, struct fdev_itf *itf, void *closure_itf)
{
	fdev->itf = itf;
	fdev->closure_itf = closure_itf;
}

void fdev_dispatch(struct fdev *fdev, uint32_t events)
{
	if (fdev->repeat > 0 && !--fdev->repeat && fdev->itf)
		fdev->itf->disable(fdev->closure_itf, fdev);
	if (fdev->callback)
		fdev->callback(fdev->closure_callback, events, fdev);
}

struct fdev *fdev_addref(struct fdev *fdev)
{
	if (fdev)
		__atomic_add_fetch(&fdev->refcount, 2, __ATOMIC_RELAXED);
	return fdev;
}

void fdev_unref(struct fdev *fdev)
{
	if (fdev && __atomic_sub_fetch(&fdev->refcount, 2, __ATOMIC_RELAXED) <= 1) {
		if (fdev->itf) {
			fdev->itf->disable(fdev->closure_itf, fdev);
			if (fdev->itf->unref)
				fdev->itf->unref(fdev->closure_itf);
		}
		if (fdev->refcount)
			close(fdev->fd);
		free(fdev);
	}
}

int fdev_fd(const struct fdev *fdev)
{
	return fdev->fd;
}

uint32_t fdev_events(const struct fdev *fdev)
{
	return fdev->events;
}

int fdev_repeat(const struct fdev *fdev)
{
	return fdev->repeat;
}

int fdev_autoclose(const struct fdev *fdev)
{
	return 1 & fdev->refcount;
}

static inline int is_active(struct fdev *fdev)
{
	return fdev->repeat && fdev->callback;
}

static inline void update_activity(struct fdev *fdev, int old_active)
{
	if (is_active(fdev)) {
		if (!old_active)
			fdev->itf->enable(fdev->closure_itf, fdev);
	} else {
		if (old_active)
			fdev->itf->disable(fdev->closure_itf, fdev);
	}
}

void fdev_set_callback(struct fdev *fdev, void (*callback)(void*,uint32_t,struct fdev*), void *closure)
{
	int oa;

	oa = is_active(fdev);
	fdev->callback = callback;
	fdev->closure_callback = closure;
	update_activity(fdev, oa);
}

void fdev_set_events(struct fdev *fdev, uint32_t events)
{
	if (events != fdev->events) {
		fdev->events = events;
		if (is_active(fdev))
			fdev->itf->update(fdev->closure_itf, fdev);
	}
}

void fdev_set_repeat(struct fdev *fdev, int count)
{
	int oa;

	oa = is_active(fdev);
	fdev->repeat = count;
	update_activity(fdev, oa);
}

void fdev_set_autoclose(struct fdev *fdev, int autoclose)
{
	if (autoclose)
		fdev->refcount |= (unsigned)1;
	else
		fdev->refcount &= ~(unsigned)1;
}