| 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 | |