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
|
/*
* Circular buffer implementation.
* Copyright (C) 2017 Cumulus Networks
* Quentin Young
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; see the file COPYING; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <zebra.h>
#include "ringbuf.h"
#include "memory.h"
DEFINE_MTYPE_STATIC(LIB, RINGBUFFER, "Ring buffer");
struct ringbuf *ringbuf_new(size_t size)
{
struct ringbuf *buf = XCALLOC(MTYPE_RINGBUFFER, sizeof(struct ringbuf));
buf->data = XCALLOC(MTYPE_RINGBUFFER, size);
buf->size = size;
buf->empty = true;
return buf;
}
void ringbuf_del(struct ringbuf *buf)
{
XFREE(MTYPE_RINGBUFFER, buf->data);
XFREE(MTYPE_RINGBUFFER, buf);
}
size_t ringbuf_remain(struct ringbuf *buf)
{
ssize_t diff = buf->end - buf->start;
diff += ((diff == 0) && !buf->empty) ? buf->size : 0;
diff += (diff < 0) ? buf->size : 0;
return (size_t)diff;
}
size_t ringbuf_space(struct ringbuf *buf)
{
return buf->size - ringbuf_remain(buf);
}
size_t ringbuf_put(struct ringbuf *buf, const void *data, size_t size)
{
const uint8_t *dp = data;
size_t space = ringbuf_space(buf);
size_t copysize = MIN(size, space);
size_t tocopy = copysize;
if (tocopy >= buf->size - buf->end) {
size_t ts = buf->size - buf->end;
memcpy(buf->data + buf->end, dp, ts);
buf->end = 0;
tocopy -= ts;
dp += ts;
}
memcpy(buf->data + buf->end, dp, tocopy);
buf->end += tocopy;
buf->empty = (buf->start == buf->end) && (buf->empty && !copysize);
return copysize;
}
size_t ringbuf_get(struct ringbuf *buf, void *data, size_t size)
{
uint8_t *dp = data;
size_t remain = ringbuf_remain(buf);
size_t copysize = MIN(remain, size);
size_t tocopy = copysize;
if (tocopy >= buf->size - buf->start) {
size_t ts = buf->size - buf->start;
memcpy(dp, buf->data + buf->start, ts);
buf->start = 0;
tocopy -= ts;
dp += ts;
}
memcpy(dp, buf->data + buf->start, tocopy);
buf->start = buf->start + tocopy;
buf->empty = (buf->start == buf->end) && (buf->empty || copysize);
return copysize;
}
size_t ringbuf_peek(struct ringbuf *buf, size_t offset, void *data, size_t size)
{
uint8_t *dp = data;
size_t remain = ringbuf_remain(buf);
if (offset >= remain)
return 0;
size_t copysize = MAX(MIN(remain - offset, size), (size_t)0);
size_t tocopy = copysize;
size_t cstart = (buf->start + offset) % buf->size;
if (tocopy >= buf->size - cstart) {
size_t ts = buf->size - cstart;
memcpy(dp, buf->data + cstart, ts);
cstart = 0;
tocopy -= ts;
dp += ts;
}
memcpy(dp, buf->data + cstart, tocopy);
return copysize;
}
size_t ringbuf_copy(struct ringbuf *to, struct ringbuf *from, size_t size)
{
size_t tocopy = MIN(ringbuf_space(to), size);
uint8_t *cbuf = XCALLOC(MTYPE_TMP, tocopy);
tocopy = ringbuf_peek(from, 0, cbuf, tocopy);
size_t put = ringbuf_put(to, cbuf, tocopy);
XFREE(MTYPE_TMP, cbuf);
return put;
}
void ringbuf_reset(struct ringbuf *buf)
{
buf->start = buf->end = 0;
buf->empty = true;
}
void ringbuf_wipe(struct ringbuf *buf)
{
memset(buf->data, 0x00, buf->size);
ringbuf_reset(buf);
}
|
