mirror of https://github.com/jeelabs/esp-link.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
63 lines
1.5 KiB
63 lines
1.5 KiB
#include "ringbuf.h"
|
|
|
|
/**
|
|
* \brief init a RINGBUF object
|
|
* \param r pointer to a RINGBUF object
|
|
* \param buf pointer to a byte array
|
|
* \param size size of buf
|
|
* \return 0 if successfull, otherwise failed
|
|
*/
|
|
int16_t ICACHE_FLASH_ATTR
|
|
RINGBUF_Init(RINGBUF* r, uint8_t* buf, int32_t size) {
|
|
if (r == NULL || buf == NULL || size < 2) return -1;
|
|
|
|
r->p_o = r->p_r = r->p_w = buf;
|
|
r->fill_cnt = 0;
|
|
r->size = size;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* \brief put a character into ring buffer
|
|
* \param r pointer to a ringbuf object
|
|
* \param c character to be put
|
|
* \return 0 if successfull, otherwise failed
|
|
*/
|
|
int16_t ICACHE_FLASH_ATTR
|
|
RINGBUF_Put(RINGBUF* r, uint8_t c) {
|
|
if (r->fill_cnt >= r->size)return -1; // ring buffer is full, this should be atomic operation
|
|
|
|
|
|
r->fill_cnt++; // increase filled slots count, this should be atomic operation
|
|
|
|
|
|
*r->p_w++ = c; // put character into buffer
|
|
|
|
if (r->p_w >= r->p_o + r->size) // rollback if write pointer go pass
|
|
r->p_w = r->p_o; // the physical boundary
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* \brief get a character from ring buffer
|
|
* \param r pointer to a ringbuf object
|
|
* \param c read character
|
|
* \return 0 if successfull, otherwise failed
|
|
*/
|
|
int16_t ICACHE_FLASH_ATTR
|
|
RINGBUF_Get(RINGBUF* r, uint8_t* c) {
|
|
if (r->fill_cnt <= 0)return -1; // ring buffer is empty, this should be atomic operation
|
|
|
|
|
|
r->fill_cnt--; // decrease filled slots count
|
|
|
|
|
|
*c = *r->p_r++; // get the character out
|
|
|
|
if (r->p_r >= r->p_o + r->size) // rollback if write pointer go pass
|
|
r->p_r = r->p_o; // the physical boundary
|
|
|
|
return 0;
|
|
}
|
|
|