blob: 9848da3b7b6182df3957a8ac4c9dbfe8271d693f [file] [log] [blame]
wdenk232c1502004-03-12 00:14:09 +00001/*
2 * (C) Copyright 2003
3 * Gerry Hamel, geh@ti.com, Texas Instruments
4 *
Wolfgang Denk1a459662013-07-08 09:37:19 +02005 * SPDX-License-Identifier: GPL-2.0+
wdenk232c1502004-03-12 00:14:09 +00006 */
7
8#include <common.h>
9#include <malloc.h>
10
11#include <circbuf.h>
12
13
14int buf_init (circbuf_t * buf, unsigned int size)
15{
16 assert (buf != NULL);
17
18 buf->size = 0;
19 buf->totalsize = size;
20 buf->data = (char *) malloc (sizeof (char) * size);
21 assert (buf->data != NULL);
22
23 buf->top = buf->data;
24 buf->tail = buf->data;
25 buf->end = &(buf->data[size]);
26
27 return 1;
28}
29
30int buf_free (circbuf_t * buf)
31{
32 assert (buf != NULL);
33 assert (buf->data != NULL);
34
35 free (buf->data);
36 memset (buf, 0, sizeof (circbuf_t));
37
38 return 1;
39}
40
41int buf_pop (circbuf_t * buf, char *dest, unsigned int len)
42{
43 unsigned int i;
44 char *p = buf->top;
45
46 assert (buf != NULL);
47 assert (dest != NULL);
48
49 /* Cap to number of bytes in buffer */
50 if (len > buf->size)
51 len = buf->size;
52
53 for (i = 0; i < len; i++) {
54 dest[i] = *p++;
55 /* Bounds check. */
56 if (p == buf->end) {
57 p = buf->data;
58 }
59 }
60
61 /* Update 'top' pointer */
62 buf->top = p;
63 buf->size -= len;
64
65 return len;
66}
67
68int buf_push (circbuf_t * buf, const char *src, unsigned int len)
69{
70 /* NOTE: this function allows push to overwrite old data. */
71 unsigned int i;
72 char *p = buf->tail;
73
74 assert (buf != NULL);
75 assert (src != NULL);
76
77 for (i = 0; i < len; i++) {
78 *p++ = src[i];
79 if (p == buf->end) {
80 p = buf->data;
81 }
82 /* Make sure pushing too much data just replaces old data */
83 if (buf->size < buf->totalsize) {
84 buf->size++;
85 } else {
86 buf->top++;
87 if (buf->top == buf->end) {
88 buf->top = buf->data;
89 }
90 }
91 }
92
93 /* Update 'tail' pointer */
94 buf->tail = p;
95
96 return len;
97}