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 = 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 68 int 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 } 98