kernel/ringbuffer.c


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#include "ringbuffer.h"
#include "kmalloc.h"
#include "log.h"
#include "asm_x86.h"

ringbuffer ringbuffer_init(uint32_t size)
{
    ringbuffer f;
    f.data=kballoc(size);
    f.size=size*4096;
    f.front=0;
    f.back=0;
    return f;
}

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

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

bool ringbuffer_empty(ringbuffer* f)
{
    return(f->front==f->back);
}

bool ringbuffer_has(ringbuffer* f)
{
    return !ringbuffer_empty(f);
}

bool ringbuffer_put(ringbuffer* f,uint8_t c)
{
    if(ringbuffer_full(f))
    {
        klog("ringbuffer is full!");
        return false; 
    }

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

    return true;
}

uint8_t ringbuffer_get(ringbuffer* f)
{
    if(ringbuffer_empty(f))return 0; // indistinguishable from value 0 :( // TODO

    uint8_t c = f->data[f->front];
    f->front++;
    f->front%=f->size;
    return c;
}

// TODO //

uint32_t ringbuffer_write(ringbuffer* f, uint8_t *buf, uint32_t size)
{
    return 0;
}

uint32_t ringbuffer_read(ringbuffer* f, uint8_t *buf, uint32_t size)
{
    return 0;
}