59 lines
No EOL
1.1 KiB
C
59 lines
No EOL
1.1 KiB
C
|
|
#include "ringb.h"
|
|
void ringb_init(struct ringb *ring, uint8_t *buf, int len)
|
|
{
|
|
ring->buf_len = len;
|
|
ring->buf = buf;
|
|
ring->idx_r = 0;
|
|
ring->idx_w = 0;
|
|
}
|
|
|
|
int ringb_get(struct ringb *ring) {
|
|
#if 1
|
|
int rval;
|
|
if (ring->idx_r != ring->idx_w) {
|
|
rval = ring->buf[ring->idx_r];
|
|
ring->idx_r = (ring->idx_r + 1) % ring->buf_len;
|
|
return rval;
|
|
}
|
|
return -1;
|
|
#else
|
|
if (((ring->idx_w - ring->idx_r) % ring->buf_len) >= 0) {
|
|
int rval = ring->buf[ring->idx_r];
|
|
ring->idx_r = (ring->idx_r + 1) % ring->buf_len;
|
|
return rval;
|
|
} else {
|
|
return -1;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
bool ringb_put(struct ringb *ring, uint8_t c) {
|
|
#if 1
|
|
unsigned int next = (ring->idx_w + 1) % ring->buf_len;
|
|
if (next != ring->idx_r) {
|
|
ring->buf[ring->idx_w] = c;
|
|
ring->idx_w = next;
|
|
return true;
|
|
}
|
|
return false;
|
|
#else
|
|
if (((ring->idx_w - ring->idx_r) % ring->buf_len) == 0) {
|
|
return false;
|
|
}
|
|
ring->buf[ring->idx_w] = c;
|
|
ring->idx_w = (ring->idx_w + 1) % ring->buf_len;
|
|
return true;
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
void ringb_flush(struct ringb *ring) {
|
|
ring->idx_r = 0;
|
|
ring->idx_w = 0;
|
|
}
|
|
|
|
int ringb_depth(struct ringb *ring) {
|
|
return ((unsigned int)(ring->idx_w - ring->idx_r) % ring->buf_len);
|
|
} |