kernel/ringbuffer.c


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#include "ringbuffer.h"
#include "kmalloc.h"

ringbuffer ringbuffer_init(uint32_t size)
{
    ringbuffer f;
    f.data=kballoc(size);
    f.size=size*4096;
    f.front=f.size-1;
    f.back=f.size-1;
    return f;
}

void ringbuffer_free(ringbuffer *f)
{
    kbfree(f->data);
}

bool ringbuffer_put(ringbuffer* f,uint8_t c)
{
    if(ringbuffer_full(f))return false;

    f->data[f->back]=c;
    f->back--;
    f->back+=f->size;
    f->back%=f->size;
    return true;
}

bool ringbuffer_full(ringbuffer* f)
{
    if((f->back-1+f->size)%f->size==f->front)
    {
	return true;
    }
    return false;
}

bool ringbuffer_has(ringbuffer* f)
{
    bool res=true;

    if(f->front==f->back)
	res=false;
    return res;
}

uint8_t ringbuffer_get(ringbuffer* f)
{
    char c;

    if(f->front==f->back)
    {
	return 0;
    }

    c=f->data[f->front];

    f->front--;
    f->front+=f->size;
    f->front%=f->size;
    return c;
}