1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * (C) Copyright 2003 4 * Gerry Hamel, geh (at) ti.com, Texas Instruments 5 */ 6 7 #include <common.h> 8 #include <malloc.h> 9 10 #include <circbuf.h> 11 12 13 int buf_init (circbuf_t * buf, unsigned int size) 14 { 15 assert (buf != NULL); 16 17 buf->size = 0; 18 buf->totalsize = size; 19 buf->data = (char *) malloc (sizeof (char) * size); 20 assert (buf->data != NULL); 21 22 buf->top = buf->data; 23 buf->tail = buf->data; 24 buf->end = &(buf->data[size]); 25 26 return 1; 27 } 28 29 int buf_free (circbuf_t * buf) 30 { 31 assert (buf != NULL); 32 assert (buf->data != NULL); 33 34 free (buf->data); 35 memset (buf, 0, sizeof (circbuf_t)); 36 37 return 1; 38 } 39 40 int buf_pop (circbuf_t * buf, char *dest, unsigned int len) 41 { 42 unsigned int i; 43 char *p; 44 45 assert (buf != NULL); 46 assert (dest != NULL); 47 48 p = buf->top; 49 50 /* Cap to number of bytes in buffer */ 51 if (len > buf->size) 52 len = buf->size; 53 54 for (i = 0; i < len; i++) { 55 dest[i] = *p++; 56 /* Bounds check. */ 57 if (p == buf->end) { 58 p = buf->data; 59 } 60 } 61 62 /* Update 'top' pointer */ 63 buf->top = p; 64 buf->size -= len; 65 66 return len; 67 } 68 69 int buf_push (circbuf_t * buf, const char *src, unsigned int len) 70 { 71 /* NOTE: this function allows push to overwrite old data. */ 72 unsigned int i; 73 char *p; 74 75 assert (buf != NULL); 76 assert (src != NULL); 77 78 p = buf->tail; 79 80 for (i = 0; i < len; i++) { 81 *p++ = src[i]; 82 if (p == buf->end) { 83 p = buf->data; 84 } 85 /* Make sure pushing too much data just replaces old data */ 86 if (buf->size < buf->totalsize) { 87 buf->size++; 88 } else { 89 buf->top++; 90 if (buf->top == buf->end) { 91 buf->top = buf->data; 92 } 93 } 94 } 95 96 /* Update 'tail' pointer */ 97 buf->tail = p; 98 99 return len; 100 } 101
