#include <stdlib.h>
#include <string.h>
#include "exhaust.h"
#include "pspace.h"

field_t
pspace_get(const pspace_t *p, u32_t paddr)
{
    paddr = paddr % p->len;
    return paddr==0 ? p->lastresult : p->mem[paddr];
}

void
pspace_set(pspace_t *p, u32_t paddr, field_t val)
{
    paddr = paddr % p->len;
    if ( paddr == 0 ) {
	p->lastresult = val;
    } else {
	p->mem[paddr] = val;
    }
}

void
pspace_clear(pspace_t *p)
{
    p->lastresult = 0;
    memset(p->mem, 0, sizeof(field_t)*p->len);
}

void
pspace_free(pspace_t *p)
{
    if (p) {
	if (p->ownmem){
	    free(p->ownmem);
	}
	free(p);
    }
}

pspace_t *
pspace_alloc(u32_t pspacesize)
{
    pspace_t *p;
    if (( p = (pspace_t*)malloc(sizeof(pspace_t)))) {
	p->len = pspacesize;
	if (!( p->ownmem = (field_t*)malloc(sizeof(field_t)*p->len))) {
	    pspace_free(p);
	    p = NULL;
	}
	p->mem = p->ownmem;
    }
    return p;
}


void
pspace_share(const pspace_t *shared, pspace_t *sharer)
{
    sharer->mem = shared->mem;
}

void
pspace_privatise(pspace_t *p)
{
    p->mem = p->ownmem;
}