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#define FOOLOS_MODULE_NAME "ringbuffer"
#include "ringbuffer.h"
// TODO: this is disabled because a kb interrupt can occur anytime
// and the kernel will need to access the ringbuffer while we are accessing!
// DO WE need a spinlock in general? do not use a global one anyway!!!!
//static int sl=9;
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;
}
bool ringbuffer_put(ringbuffer* f,uint8_t c)
{
// x86_cli();
if((f->back-1+f->size)%f->size==f->front)
{
// x86_sti();
return false;
}
f->data[f->back]=c;
f->back--;
f->back+=f->size;
f->back%=f->size;
// x86_sti();
return true;
}
bool ringbuffer_has(ringbuffer* f)
{
// x86_cli();
bool res=true;
if(f->front==f->back)
res=false;
// x86_sti();
return res;
}
uint8_t ringbuffer_get(ringbuffer* f) // non blocking . please check first
{
// x86_cli();
char c;
if(f->front==f->back)
{
// x86_sti();
return ' ';
}
c=f->data[f->front];
f->front--;
f->front+=f->size;
f->front%=f->size;
// x86_sti();
return c;
}
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