rt-thread-official/examples/kernel/semaphore_buffer_worker.c

274 lines
7.6 KiB
C
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* 程序清单:信号量实现生产者消费者间的互斥
*
* 在这个程序中会创建两个线程一个是生成者线程worker一个是消费者线程thread
*
* 在数据信息生产、消费的过程中worker负责把数据将写入到环形buffer中而thread
* 则从环形buffer中读出。
*/
#include <rtthread.h>
#include "tc_comm.h"
/* 一个环形buffer的实现 */
struct rb
{
rt_uint16_t read_index, write_index;
rt_uint8_t *buffer_ptr;
rt_uint16_t buffer_size;
};
/* 指向信号量控制块的指针 */
static rt_sem_t sem = RT_NULL;
/* 指向线程控制块的指针 */
static rt_thread_t tid = RT_NULL, worker = RT_NULL;
/* 环形buffer的内存块用数组体现出来 */
#define BUFFER_SIZE 256
#define BUFFER_ITEM 32
static rt_uint8_t working_buffer[BUFFER_SIZE];
struct rb working_rb;
/* 初始化环形buffersize指的是buffer的大小。注这里并没对数据地址对齐做处理 */
static void rb_init(struct rb* rb, rt_uint8_t *pool, rt_uint16_t size)
{
RT_ASSERT(rb != RT_NULL);
/* 对读写指针清零*/
rb->read_index = rb->write_index = 0;
/* 设置环形buffer的内存数据块 */
rb->buffer_ptr = pool;
rb->buffer_size = size;
}
/* 向环形buffer中写入数据 */
static rt_bool_t rb_put(struct rb* rb, const rt_uint8_t *ptr, rt_uint16_t length)
{
rt_size_t size;
/* 判断是否有足够的剩余空间 */
if (rb->read_index > rb->write_index)
size = rb->read_index - rb->write_index;
else
size = rb->buffer_size - rb->write_index + rb->read_index;
/* 没有多余的空间 */
if (size < length) return RT_FALSE;
if (rb->read_index > rb->write_index)
{
/* read_index - write_index 即为总的空余空间 */
memcpy(&rb->buffer_ptr[rb->write_index], ptr, length);
rb->write_index += length;
}
else
{
if (rb->buffer_size - rb->write_index > length)
{
/* write_index 后面剩余的空间有足够的长度 */
memcpy(&rb->buffer_ptr[rb->write_index], ptr, length);
rb->write_index += length;
}
else
{
/*
* write_index 后面剩余的空间不存在足够的长度,需要把部分数据复制到
* 前面的剩余空间中
*/
memcpy(&rb->buffer_ptr[rb->write_index], ptr,
rb->buffer_size - rb->write_index);
memcpy(&rb->buffer_ptr[0], &ptr[rb->buffer_size - rb->write_index],
length - (rb->buffer_size - rb->write_index));
rb->write_index = length - (rb->buffer_size - rb->write_index);
}
}
return RT_TRUE;
}
/* 从环形buffer中读出数据 */
static rt_bool_t rb_get(struct rb* rb, rt_uint8_t *ptr, rt_uint16_t length)
{
rt_size_t size;
/* 判断是否有足够的数据 */
if (rb->read_index > rb->write_index)
size = rb->buffer_size - rb->read_index + rb->write_index;
else
size = rb->write_index - rb->read_index;
/* 没有足够的数据 */
if (size < length) return RT_FALSE;
if (rb->read_index > rb->write_index)
{
if (rb->buffer_size - rb->read_index > length)
{
/* read_index的数据足够多直接复制 */
memcpy(ptr, &rb->buffer_ptr[rb->read_index], length);
rb->read_index += length;
}
else
{
/* read_index的数据不够需要分段复制 */
memcpy(ptr, &rb->buffer_ptr[rb->read_index],
rb->buffer_size - rb->read_index);
memcpy(&ptr[rb->buffer_size - rb->read_index], &rb->buffer_ptr[0],
length - rb->buffer_size + rb->read_index);
rb->read_index = length - rb->buffer_size + rb->read_index;
}
}
else
{
/*
* read_index要比write_index小总的数据量够前面已经有总数据量的判
* 断),直接复制出数据。
*/
memcpy(ptr, &rb->buffer_ptr[rb->read_index], length);
rb->read_index += length;
}
return RT_TRUE;
}
/* 生产者线程入口 */
static void thread_entry(void* parameter)
{
rt_bool_t result;
rt_uint8_t data_buffer[BUFFER_ITEM + 1];
while (1)
{
/* 持有信号量 */
rt_sem_take(sem, RT_WAITING_FOREVER);
/* 从环buffer中获得数据 */
result = rb_get(&working_rb, &data_buffer[0], BUFFER_ITEM);
/* 释放信号量 */
rt_sem_release(sem);
data_buffer[BUFFER_ITEM] = '\0';
if (result == RT_TRUE)
{
/* 获取数据成功,打印数据 */
rt_kprintf("%s\n", data_buffer);
}
/* 做一个5 OS Tick的休眠 */
rt_thread_delay(5);
}
}
/* worker线程入口 */
static void worker_entry(void* parameter)
{
rt_bool_t result;
rt_uint32_t index, setchar;
rt_uint8_t data_buffer[BUFFER_ITEM];
setchar = 0x21;
while (1)
{
/* 构造数据 */
for(index = 0; index < BUFFER_ITEM; index++)
{
data_buffer[index] = setchar;
if (++setchar == 0x7f)
setchar = 0x21;
}
/* 持有信号量 */
rt_sem_take(sem, RT_WAITING_FOREVER);
/* 把数据放到环形buffer中 */
result = rb_put(&working_rb, &data_buffer[0], BUFFER_ITEM);
if (result == RT_FALSE)
{
rt_kprintf("put error\n");
}
/* 释放信号量 */
rt_sem_release(sem);
/* 放入成功做一个10 OS Tick的休眠 */
rt_thread_delay(10);
}
}
int semaphore_buffer_worker_init()
{
/* 初始化ring buffer */
rb_init(&working_rb, working_buffer, BUFFER_SIZE);
/* 创建信号量 */
sem = rt_sem_create("sem", 1, RT_IPC_FLAG_FIFO);
if (sem == RT_NULL)
{
tc_stat(TC_STAT_END | TC_STAT_FAILED);
return 0;
}
/* 创建线程1 */
tid = rt_thread_create("thread",
thread_entry, RT_NULL, /* 线程入口是thread_entry, 入口参数是RT_NULL */
THREAD_STACK_SIZE, THREAD_PRIORITY, THREAD_TIMESLICE);
if (tid != RT_NULL)
rt_thread_startup(tid);
else
tc_stat(TC_STAT_END | TC_STAT_FAILED);
/* 创建线程2 */
worker = rt_thread_create("worker",
worker_entry, RT_NULL, /* 线程入口是worker_entry, 入口参数是RT_NULL */
THREAD_STACK_SIZE, THREAD_PRIORITY, THREAD_TIMESLICE);
if (worker != RT_NULL)
rt_thread_startup(worker);
else
tc_stat(TC_STAT_END | TC_STAT_FAILED);
return 0;
}
#ifdef RT_USING_TC
static void _tc_cleanup()
{
/* 调度器上锁,上锁后,将不再切换到其他线程,仅响应中断 */
rt_enter_critical();
/* 删除信号量 */
if (sem != RT_NULL)
rt_sem_delete(sem);
/* 删除线程 */
if (tid != RT_NULL && tid->stat != RT_THREAD_CLOSE)
rt_thread_delete(tid);
if (worker != RT_NULL && worker->stat != RT_THREAD_CLOSE)
rt_thread_delete(worker);
/* 调度器解锁 */
rt_exit_critical();
/* 设置TestCase状态 */
tc_done(TC_STAT_PASSED);
}
int _tc_semaphore_buffer_worker()
{
/* 设置TestCase清理回调函数 */
tc_cleanup(_tc_cleanup);
semaphore_buffer_worker_init();
/* 返回TestCase运行的最长时间 */
return 100;
}
/* 输出函数命令到finsh shell中 */
FINSH_FUNCTION_EXPORT(_tc_semaphore_buffer_worker, a buffer worker with semaphore example);
#else
/* 用户应用入口 */
int rt_application_init()
{
semaphore_buffer_worker_init();
return 0;
}
#endif