#include <stdlib.h>

#define ACHUNK 1024

#include "allocv.h"

struct allocv {
  int n;
  int nmax;
  int achunks;
  int esize;
  char **v;
  } ;

ALLOCV *allocv_init(int sz)
{
 ALLOCV *a;

 a = malloc(sizeof(ALLOCV));
 a->n = 0;
 a->nmax = 0;
 a->achunks = 0;
 a->esize = sz;
 a->v = 0;
 return(a);
}

int allocv_new(ALLOCV *a)
{
 int x;

 x = a->n ++;
 if (x >= a->nmax)
  { a->achunks ++;
    a->nmax = a->achunks * ACHUNK;
    a->v = realloc(a->v,a->achunks*sizeof(char *));
    a->v[a->achunks-1] = malloc(ACHUNK*a->esize);
  }
 return(x);
}

void *allocv_el(ALLOCV *a, unsigned int x)
{
 if (x >= a->n) abort();
 return(a->v[x/ACHUNK]+((x%ACHUNK)*a->esize));
}

int allocv_okx(ALLOCV *a, int x)
{
 return((x >= 0) && (x < a->n));
}

int allocv_n(ALLOCV *a)
{
 return(a->n);
}