1 /* 2 * (C) Copyright 2003 3 * Gerry Hamel, geh@ti.com, Texas Instruments 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #include <common.h> 9 #include <malloc.h> 10 11 #include <circbuf.h> 12 13 14 int 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 30 int 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 41 int buf_pop (circbuf_t * buf, char *dest, unsigned int len) 42 { 43 unsigned int i; 44 char *p; 45 46 assert (buf != NULL); 47 assert (dest != NULL); 48 49 p = buf->top; 50 51 /* Cap to number of bytes in buffer */ 52 if (len > buf->size) 53 len = buf->size; 54 55 for (i = 0; i < len; i++) { 56 dest[i] = *p++; 57 /* Bounds check. */ 58 if (p == buf->end) { 59 p = buf->data; 60 } 61 } 62 63 /* Update 'top' pointer */ 64 buf->top = p; 65 buf->size -= len; 66 67 return len; 68 } 69 70 int buf_push (circbuf_t * buf, const char *src, unsigned int len) 71 { 72 /* NOTE: this function allows push to overwrite old data. */ 73 unsigned int i; 74 char *p; 75 76 assert (buf != NULL); 77 assert (src != NULL); 78 79 p = buf->tail; 80 81 for (i = 0; i < len; i++) { 82 *p++ = src[i]; 83 if (p == buf->end) { 84 p = buf->data; 85 } 86 /* Make sure pushing too much data just replaces old data */ 87 if (buf->size < buf->totalsize) { 88 buf->size++; 89 } else { 90 buf->top++; 91 if (buf->top == buf->end) { 92 buf->top = buf->data; 93 } 94 } 95 } 96 97 /* Update 'tail' pointer */ 98 buf->tail = p; 99 100 return len; 101 } 102