You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
89 lines
2.8 KiB
C
89 lines
2.8 KiB
C
// Resource/Inspiration: https://embedjournal.com/implementing-circular-buffer-embedded-c/
|
|
|
|
/*
|
|
Penguin's Circular Buffer -- a simple floating queue designed for low memory usage (mainly for embedded)
|
|
|
|
This is a ring buffer with limited capabilities. It is meant as a container for moving data.
|
|
Normally included features such as checks to see if the buffer is full or empty have been omitted
|
|
because this type of buffer is being implemented mainly for sensor data usage. Data is almost never read
|
|
individually, and even if it is, it isn't meant to be cleared on read. It is a simple moving buffer that
|
|
automatically writes over old data for the purpose of keeping track of the most up to date data.
|
|
|
|
Notes:
|
|
- Initialization is mandatory using p_cb_<type>_init.
|
|
- If a circular buffer is not initialized, you will run into a LOT of hard-to-debug problems. Just initialize it.
|
|
- By default, all cb types should be defined as disabled. This is to save on size. Enable the ones you want to use.
|
|
|
|
Behavior:
|
|
- Oldest data is overwritten
|
|
- popping of data isn't implemented. If this feature is required, use a ring buffer.
|
|
|
|
Acronyms:
|
|
- p: penguin
|
|
- pb: penguin buffer
|
|
- cb: circular buffer
|
|
- uX, where X is bit size: unsigned X bit integer
|
|
- iX, where X is bit size: signed X bit integer
|
|
|
|
Note: I wrote this like 3 years ago or something. I hope it works.
|
|
*/
|
|
|
|
#ifndef _PCIRCULARBUFFER_H_
|
|
#define _PCIRCULARBUFFER_H_
|
|
|
|
#include "p_serial_mgr.h"
|
|
#include <stdbool.h>
|
|
#include <stdint.h>
|
|
|
|
#ifdef _DEBUG
|
|
#define PC_CB_DEBUG
|
|
#endif
|
|
|
|
// Max size is 65535 (2^16 - 1) so variables can be safely set 16 bits (unsigned)
|
|
// If you want to change this, you'll need to change the sizes of all heads and max lengths
|
|
#define PB_CB_MAX_BUFFER_SIZE (65535)
|
|
|
|
typedef enum PB_CB_STATUS
|
|
{
|
|
PB_CB_GOOD = 0,
|
|
PB_CB_BAD = 1,
|
|
PB_CB_BAD_BUFFER_SIZE = 2,
|
|
PB_CB_NULL_BUFFER = 3,
|
|
PB_CB_NULL_CBUFFER = 4
|
|
} PB_CB_STATUS;
|
|
|
|
typedef struct p_cb_u8
|
|
{
|
|
uint8_t *buffer;
|
|
uint16_t head;
|
|
uint16_t max_len;
|
|
// Signifies the buffer being filled at least once.
|
|
// Useful for initializing sensor data
|
|
bool b_filled;
|
|
// Signifies the buffer being empty
|
|
// Useful for knowing if data is being received
|
|
bool b_empty;
|
|
|
|
PB_CB_STATUS (*push)(struct p_cb_u8 *cbuffer, uint8_t value);
|
|
PB_CB_STATUS (*empty)(struct p_cb_u8 *cbuffer);
|
|
} p_cb_u8;
|
|
|
|
PB_CB_STATUS p_cb_u8_init(p_cb_u8 *circ_buffer, uint8_t *buff, uint32_t max_length);
|
|
|
|
typedef struct p_cb_serial_pkt_t
|
|
{
|
|
serial_pkt_t *buffer;
|
|
uint16_t head;
|
|
uint16_t max_len;
|
|
bool b_filled;
|
|
// Signifies the buffer being empty
|
|
// Useful for knowing if data is being received
|
|
bool b_empty;
|
|
|
|
PB_CB_STATUS (*push)(struct p_cb_serial_pkt_t *cbuffer, serial_pkt_t value);
|
|
PB_CB_STATUS (*empty)(struct p_cb_serial_pkt_t *cbuffer);
|
|
} p_cb_serial_pkt_t;
|
|
|
|
PB_CB_STATUS p_cb_serial_pkt_init(p_cb_serial_pkt_t *inst, serial_pkt_t *buff, uint32_t max_length);
|
|
#endif
|