1 /*
2 * This file is part of the MicroPython project, http://micropython.org/
3 *
4 * The MIT License (MIT)
5 *
6 * Copyright (c) 2019 Jim Mussared
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 */
26 #include "ringbuf.h"
27
ringbuf_get16(ringbuf_t * r)28 int ringbuf_get16(ringbuf_t *r) {
29 int v = ringbuf_peek16(r);
30 if (v == -1) {
31 return v;
32 }
33 r->iget += 2;
34 if (r->iget >= r->size) {
35 r->iget -= r->size;
36 }
37 return v;
38 }
39
ringbuf_peek16(ringbuf_t * r)40 int ringbuf_peek16(ringbuf_t *r) {
41 if (r->iget == r->iput) {
42 return -1;
43 }
44 uint32_t iget_a = r->iget + 1;
45 if (iget_a == r->size) {
46 iget_a = 0;
47 }
48 if (iget_a == r->iput) {
49 return -1;
50 }
51 return (r->buf[r->iget] << 8) | (r->buf[iget_a]);
52 }
53
ringbuf_put16(ringbuf_t * r,uint16_t v)54 int ringbuf_put16(ringbuf_t *r, uint16_t v) {
55 uint32_t iput_a = r->iput + 1;
56 if (iput_a == r->size) {
57 iput_a = 0;
58 }
59 if (iput_a == r->iget) {
60 return -1;
61 }
62 uint32_t iput_b = iput_a + 1;
63 if (iput_b == r->size) {
64 iput_b = 0;
65 }
66 if (iput_b == r->iget) {
67 return -1;
68 }
69 r->buf[r->iput] = (v >> 8) & 0xff;
70 r->buf[iput_a] = v & 0xff;
71 r->iput = iput_b;
72 return 0;
73 }
74