一个fifo工程简单模板
gen_fifo.h文件
#ifndef GEN_FIFO_H
#define GEN_FIFO_H#ifdef __cplusplus
extern "C" {
#endiftypedef struct kfifo {unsigned int in;unsigned int out;unsigned int mask;unsigned int esize;unsigned char *buffer;
} gen_fifo_t;/*** @brief 获取FIFO内当前元素个数（内联实现）* @param fifo 指向FIFO结构体的指针* @return FIFO内有效元素个数*/
static inline unsigned int gen_fifo_len(gen_fifo_t *fifo) {return fifo->in - fifo->out;
}/*** @brief 获取FIFO内空闲元素个数（内联实现）* @param fifo 指向FIFO结构体的指针* @return FIFO内空闲元素个数*/
static inline unsigned int gen_fifo_unused(gen_fifo_t *fifo) {return ((fifo->mask + 1) / fifo->esize) - gen_fifo_len(fifo);
}/*** @brief 判断FIFO是否为空（内联实现）* @param fifo 指向FIFO结构体的指针* @return 1-空，0-非空*/
static inline unsigned char gen_fifo_is_empty(gen_fifo_t *fifo) {return gen_fifo_len(fifo) == 0;
}/*** @brief 判断FIFO是否为满（内联实现）* @param fifo 指向FIFO结构体的指针* @return 1-满，0-非满*/
static inline unsigned char gen_fifo_is_full(gen_fifo_t *fifo) {return gen_fifo_unused(fifo) == 0;
}unsigned int gen_fifo_out(gen_fifo_t *fifo, void *buf, unsigned int len);
unsigned int gen_fifo_in(gen_fifo_t *fifo, const void *buf, unsigned int len);
void gen_fifo_init(gen_fifo_t *fifo, unsigned char *buffer, unsigned int size, unsigned int esize);#ifdef __cplusplus
}
#endif#endif /* GEN_FIFO_H */
gen_fifo.c文件
#include <stdint.h>
#include <string.h>
#include <stdio.h>
#include "gen_fifo.h"/*** @brief FIFO初始化函数* @param fifo 指向FIFO结构体的指针* @param buffer 指向静态缓冲区的指针* @param size 缓冲区总字节数* @param esize 单个元素大小*/
void gen_fifo_init(gen_fifo_t *fifo, unsigned char *buffer,unsigned int size, unsigned int esize)
{if (fifo == NULL || buffer == NULL || size == 0 || esize == 0)return;if ((size & (size - 1)) != 0 || (size % esize) != 0)return;fifo->buffer = buffer;fifo->esize = esize;fifo->in = 0;fifo->out = 0;fifo->mask = size - 1;
}// 内部数据入队拷贝
static void gen_fifo_copy_in(gen_fifo_t *fifo, const void *src,unsigned int len, unsigned int off)
{unsigned int size = fifo->mask + 1;unsigned int esize = fifo->esize;unsigned int l;off &= fifo->mask;if (esize != 1) {off *= esize;size *= esize;len *= esize;}l = len < (size - off) ? len : (size - off);memcpy(fifo->buffer + off, src, l);memcpy(fifo->buffer, (const unsigned char *)src + l, len - l);
}/*** @brief FIFO入队函数* @param fifo 指向FIFO结构体的指针* @param buf 指向待入队数据的缓冲区* @param len 待入队元素个数* @return 实际入队元素个数*/
unsigned int gen_fifo_in(gen_fifo_t *fifo, const void *buf, unsigned int len)
{unsigned int l;if (fifo == NULL || buf == NULL || len == 0)return 0;l = gen_fifo_unused(fifo);if (len > l)len = l;gen_fifo_copy_in(fifo, buf, len, fifo->in);fifo->in += len;return len;
}// 内部数据出队拷贝
static void gen_fifo_copy_out(gen_fifo_t *fifo, void *dst,unsigned int len, unsigned int off)
{unsigned int size = fifo->mask + 1;unsigned int esize = fifo->esize;unsigned int l;off &= fifo->mask;if (esize != 1) {off *= esize;size *= esize;len *= esize;}l = len < (size - off) ? len : (size - off);memcpy(dst, fifo->buffer + off, l);memcpy((unsigned char *)dst + l, fifo->buffer, len - l);
}/*** @brief FIFO出队函数* @param fifo 指向FIFO结构体的指针* @param buf 指向存放出队数据的缓冲区* @param len 待出队元素个数* @return 实际出队元素个数*/
unsigned int gen_fifo_out(gen_fifo_t *fifo, void *buf, unsigned int len)
{unsigned int l;if (fifo == NULL || buf == NULL || len == 0)return 0;l = gen_fifo_len(fifo);if (len > l)len = l;gen_fifo_copy_out(fifo, buf, len, fifo->out);fifo->out += len;return len;
}