/*
* Copyright (C) 2018 edgar1470@gmail.com
*
*/
#include "xm_ringbuffer.h"
#define CACHE_BUFFER_SIZE (1024)
int8_t cache[RING_BUFFER_SIZE][1024] = {{0}};
/*
* return ther initial state of the ring buffer
* @param buffer The buffer to be initialized.
* @param size The buffer size which should be power of two.
* @return -1 if buffer is null; 0 success.
*/
int32_t xm_ringbuffer_init(xm_ringbuffer_t *buffer, uint32_t size)
{
int32_t r = -1;
if (buffer) {
buffer->head = 0;
buffer->tail = 0;
buffer->size = size; /* TODO: force size */
buffer->data = malloc(size);
if (buffer->data) {
r = 0;
}
}
return r;
}
/*
* Returns whether the ring buffer is full.
* @param buffer The buffer for which it should be returned whether it is full.
* @return 1 if full; 0 otherwise.
*/
int32_t xm_ringbuffer_is_full(xm_ringbuffer_t *buffer) {
return (((buffer->head + 1) % buffer->size) == buffer->tail);
}
/*
* Returns whether the ring buffer is empty.
* @param buffer The buffer for which it should be returned whether it is empty.
* @return 1 if empty; 0 otherwise.
*/
int32_t xm_ringbuffer_is_empty(xm_ringbuffer_t *buffer) {
return (buffer->head == buffer->tail);
}
int32_t xm_ringbuffer_write(xm_ringbuffer_t *buffer, uint32_t data)
{
int32_t r = -1;
if (buffer) {
if (xm_ringbuffer_is_full(buffer)) {
/* ring buffer is full just overwirte the oldest one */
buffer->tail = (buffer->tail + 1) % buffer->size;
}
buffer->data[buffer->head] = data;
buffer->head = (buffer->head + 1) % buffer->size;
r = 0;
}
return r;
}
int32_t xm_ringbuffer_read(xm_ringbuffer_t *buffer, uint32_t *data)
{
int32_t r = -1;
if (xm_ringbuffer_is_empty(buffer)) {
return r;
}
*data = buffer->data[buffer->tail];
buffer->tail = (buffer->tail + 1) % buffer->size;
r = 0;
return r;
}
