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 | |
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 | |
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 | |
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 | |