#include <stdio.h>

#include <u.h>
#include <libc.h>
#include <stdio.h>
#include "cpp.h"

/*
* A hideset is a null-terminated array of Nlist pointers.
* They are referred to by indices in the hidesets array.
* Hideset 0 is empty.
*/

#define HSSIZ 32
typedef Nlist **Hideset;
Hideset *hidesets;
int nhidesets = 0;
int maxhidesets = 3;
int inserths(Hideset, Hideset, Nlist *);

/*
* Test for membership in a hideset
*/
int
checkhideset(int hs, Nlist *np)
{
Hideset hsp;

if (hs>=nhidesets)
abort();
for (hsp = hidesets[hs]; *hsp; hsp++) {
if (*hsp == np)
return 1;
}
return 0;
}

/*
* Return the (possibly new) hideset obtained by adding np to hs.
*/
int
newhideset(int hs, Nlist *np)
{
int i, len;
Nlist *nhs[HSSIZ+3];
Hideset hs1, hs2;

len = inserths(nhs, hidesets[hs], np);
for (i=0; i<nhidesets; i++) {
for (hs1=nhs, hs2=hidesets[i]; *hs1==*hs2; hs1++, hs2++)
if (*hs1 == NULL)
return i;
}
if (len>=HSSIZ)
return hs;
if (nhidesets >= maxhidesets) {
maxhidesets = 3*maxhidesets/2+1;
hidesets = (Hideset *)dorealloc(hidesets, (sizeof (Hideset *))*maxhidesets);
}
hs1 = (Hideset)domalloc(len*sizeof(Hideset));
memmove(hs1, nhs, len*sizeof(Hideset));
hidesets[nhidesets] = hs1;
return nhidesets++;
}

int
inserths(Hideset dhs, Hideset shs, Nlist *np)
{
Hideset odhs = dhs;

while (*shs && *shs < np)
*dhs++ = *shs++;
if (*shs != np)
*dhs++ = np;
do {
*dhs++ = *shs;
} while (*shs++);
return dhs - odhs;
}

/*
* Hideset union
*/
int
unionhideset(int hs1, int hs2)
{
Hideset hp;

for (hp = hidesets[hs2]; *hp; hp++)
hs1 = newhideset(hs1, *hp);
return hs1;
}

void
iniths(void)
{
hidesets = (Hideset *)domalloc(maxhidesets*sizeof(Hideset *));
hidesets[0] = (Hideset)domalloc(sizeof(Hideset));
*hidesets[0] = NULL;
nhidesets++;
}

void
prhideset(int hs)
{
Hideset np;

for (np = hidesets[hs]; *np; np++) {
fprintf(stderr, (char*)(*np)->name, (*np)->len);
fprintf(stderr, " ", 1);
}
}