| commit | author | age | ||
| d6b4a7 | 1 | /********************************************************************************* |
| G | 2 | * Copyright: (C) 2023 LingYun IoT System Studio. |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * Filename: ringbuf.c | |
| 6 | * Description: This file is common ring buffer API functions | |
| 7 | * | |
| 8 | * Version: 1.0.0(11/08/23) | |
| 9 | * Author: Guo Wenxue <guowenxue@gmail.com> | |
| 10 | * ChangeLog: 1, Release initial version on "11/08/23 16:18:43" | |
| 11 | * | |
| 12 | ********************************************************************************/ | |
| 13 | ||
| 14 | #include <string.h> | |
| 15 | #include <assert.h> | |
| 16 | #include "ringbuf.h" | |
| 17 | ||
| 18 | void rb_init (struct ring_buffer *ring, unsigned char* buff, int size) | |
| 19 | { | |
| 20 | memset (ring, 0, sizeof (struct ring_buffer)); | |
| 21 | ring->rd_pointer = 0; | |
| 22 | ring->wr_pointer = 0; | |
| 23 | ring->buffer= buff; | |
| 24 | ring->size = size; | |
| 25 | } | |
| 26 | ||
| 27 | ||
| 28 | int rb_write (struct ring_buffer *rb, unsigned char * buf, int len) | |
| 29 | { | |
| 30 | int total; | |
| 31 | int i; | |
| 32 | ||
| 33 | /* total = len = min(space, len) */ | |
| 34 | total = rb_free_size(rb); | |
| 35 | if(len > total) | |
| 36 | len = total; | |
| 37 | else | |
| 38 | total = len; | |
| 39 | ||
| 40 | i = rb->wr_pointer; | |
| 41 | if(i + len > rb->size) | |
| 42 | { | |
| 43 | memcpy(rb->buffer + i, buf, rb->size - i); | |
| 44 | buf += rb->size - i; | |
| 45 | len -= rb->size - i; | |
| 46 | i = 0; | |
| 47 | } | |
| 48 | ||
| 49 | memcpy(rb->buffer + i, buf, len); | |
| 50 | rb->wr_pointer = i + len; | |
| 51 | return total; | |
| 52 | } | |
| 53 | ||
| 54 | ||
| 55 | int rb_free_size (struct ring_buffer *rb) | |
| 56 | { | |
| 57 | return (rb->size - 1 - rb_data_size(rb)); | |
| 58 | } | |
| 59 | ||
| 60 | ||
| 61 | int rb_read (struct ring_buffer *rb, unsigned char * buf, int max) | |
| 62 | { | |
| 63 | int total; | |
| 64 | int i; | |
| 65 | ||
| 66 | /* total = len = min(used, len) */ | |
| 67 | total = rb_data_size(rb); | |
| 68 | ||
| 69 | if(max > total) | |
| 70 | max = total; | |
| 71 | else | |
| 72 | total = max; | |
| 73 | ||
| 74 | ||
| 75 | i = rb->rd_pointer; | |
| 76 | if(i + max > rb->size) | |
| 77 | { | |
| 78 | memcpy(buf, rb->buffer + i, rb->size - i); | |
| 79 | buf += rb->size - i; | |
| 80 | max -= rb->size - i; | |
| 81 | i = 0; | |
| 82 | } | |
| 83 | ||
| 84 | memcpy(buf, rb->buffer + i, max); | |
| 85 | rb->rd_pointer = i + max; | |
| 86 | ||
| 87 | return total; | |
| 88 | } | |
| 89 | ||
| 90 | int rb_data_size (struct ring_buffer *rb) | |
| 91 | { | |
| 92 | return ((rb->wr_pointer - rb->rd_pointer) & (rb->size-1)); | |
| 93 | } | |
| 94 | ||
| 95 | void rb_clear (struct ring_buffer *rb) | |
| 96 | { | |
| 97 | memset(rb->buffer,0,rb->size); | |
| 98 | rb->rd_pointer=0; | |
| 99 | rb->wr_pointer=0; | |
| 100 | } | |
| 101 | ||
| 102 | unsigned char rb_peek(struct ring_buffer* rb, int index) | |
| 103 | { | |
| 104 | assert(index < rb_data_size(rb)); | |
| 105 | ||
| 106 | return rb->buffer[((rb->rd_pointer + index) % rb->size)]; | |
| 107 | } | |
