一、内核基础组件
- 环形队列
概述
环形队列本质上就是支持先入先出操作的环形buffer，是系统的一个基础组件，通常用来作为实现上层机制的底层数据容器。
API讲解
编程实例
1、编写main.c示例代码：
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "usart.h"
#include "gpio.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "cmsis_os.h"
#include "stdio.h"
#include "tos_k.h"
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
#define STK_SIZE_TASK_DEMO 512
#define PRIO_TASK_DEMO 4
k_stack_t stack_task_demo[STK_SIZE_TASK_DEMO];
k_task_t task_demo;
typedef struct item_st {
int a;
int b;
int c;
} item_t;
#define RING_QUEUE_ITEM_MAX 5
uint8_t ring_q_buffer[RING_QUEUE_ITEM_MAX * sizeof(item_t)];
k_ring_q_t rinq_q;
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
void entry_task_demo(void *arg)
{
k_err_t err;
int i = 0;
item_t item;
size_t item_size;
tos_ring_q_create(&rinq_q, ring_q_buffer, RING_QUEUE_ITEM_MAX, sizeof(item_t));
for (i = 0; i < RING_QUEUE_ITEM_MAX; ++i) {
printf("enqueue: %d %d %d\n", i, i, i);
item.a = i;
item.b = i;
item.c = i;
err = tos_ring_q_enqueue(&rinq_q, &item, sizeof(item_t));
if (err != K_ERR_NONE) {
printf("should never happen\n");
}
}
err = tos_ring_q_enqueue(&rinq_q, &item, sizeof(item_t));
if (err == K_ERR_RING_Q_FULL) {
printf("ring queue is full: %s\n", tos_ring_q_is_full(&rinq_q) ? "TRUE" : "FALSE");
} else {
printf("should never happen\n");
}
for (i = 0; i < RING_QUEUE_ITEM_MAX; ++i) {
err = tos_ring_q_dequeue(&rinq_q, &item, &item_size);
if (err == K_ERR_NONE) {
printf("dequeue: %d %d %d\n", item.a, item.b, item.c);
} else {
printf("should never happen\n");
}
}
err = tos_ring_q_dequeue(&rinq_q, &item, &item_size);
if (err == K_ERR_RING_Q_EMPTY) {
printf("ring queue is empty: %s\n", tos_ring_q_is_empty(&rinq_q) ? "TRUE" : "FALSE");
} else {
printf("should never happen\n");
}
}
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_USART1_UART_Init();
/* USER CODE BEGIN 2 */
tos_knl_init();
(void)tos_task_create(&task_demo, "demo", entry_task_demo, NULL,
PRIO_TASK_DEMO, stack_task_demo, STK_SIZE_TASK_DEMO,
0);
tos_knl_start();
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
2、运行效果：
源码链接
