39 lines
655 B
C
39 lines
655 B
C
#include <devbuf.h>
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#include <stdio.h>
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#include <stdlib.h>
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devbuf* devbuf_init() {
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devbuf* buf=malloc(sizeof(devbuf));
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buf->rd=0;
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buf->wr=0;
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for (int i=0;i<256;i++) {
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buf->buf[i]=EOF;
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}
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return buf;
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}
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void devbuf_add(char byte,devbuf* buf) {
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buf->buf[buf->wr]=byte;
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buf->wr++;
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if (buf->wr==buf->rd) {
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buf->wr--;
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}
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}
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int devbuf_get(devbuf* buf) {
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if (buf->buf[buf->rd]==-1) {
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buf->rd++;
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if (buf->buf[buf->rd]==-1) {
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buf->rd--;
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while (buf->buf[buf->rd]==-1);
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}
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}
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int data=buf->buf[buf->rd];
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buf->buf[buf->rd]=-1;
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buf->rd++;
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if (buf->rd>buf->wr) {
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buf->rd=buf->wr-1;
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}
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return data;
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}
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