41 lines
951 B
C
41 lines
951 B
C
#include "../include/fifo.h"
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void fifo8_init(struct FIFO8* fifo, int size, unsigned char* buf) {
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fifo->size = size;
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fifo->buf = buf;
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fifo->free = size; /* 缓冲区大小 */
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fifo->flags = 0;
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fifo->p = 0; /* 下一个数据写入位置 */
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fifo->q = 0; /* 下一个数据读出位置 */
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return;
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}
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int fifo8_put(struct FIFO8* fifo, unsigned char data) {
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if (fifo->free == 0) {
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/* 没有空间了，溢出 */
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fifo->flags |= FLAGS_OVERRUN;
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return -1;
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}
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fifo->buf[fifo->p] = data;
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fifo->p++;
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if (fifo->p == fifo->size) {
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fifo->p = 0;
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}
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fifo->free--;
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return 0;
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}
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int fifo8_get(struct FIFO8* fifo) {
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int data;
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if (fifo->free == fifo->size) {
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/* 如果缓冲区为空则返回-1 */
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return -1;
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}
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data = fifo->buf[fifo->q];
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fifo->q++;
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if (fifo->q == fifo->size) {
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fifo->q = 0;
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}
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fifo->free++;
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return data;
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} |