cutil/bitvec.cpp

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/* =================
          Include Files and Type Defines
 ==================== */
#include "bitvec.h"
#include "emalloc.h"
#include "freelist.h"
#include "callcpp.h"

#include <stdio.h>

/* =================
 Global Data Definitions and Declarations
 ==================== */
static int BitVectorCount = 0;

/* =================
              Public Code
 ==================== */
/* =============================== */
BIT_VECTOR ExpandBitVector(BIT_VECTOR Vector, int NewNumBits) { 
  return ((BIT_VECTOR) Erealloc (Vector,
    sizeof (unsigned long) *
    WordsInVectorOfSize (NewNumBits)));

}                                /* ExpandBitVector */


/* =============================== */
void FreeBitVector(BIT_VECTOR BitVector) { 
  if (BitVector) {
    memfree(BitVector); 
    BitVectorCount--;
  }
  else {
    cprintf ("%6d BITVECTOR elements in use\n", BitVectorCount);
  }

}                                /* FreeBitVector */


/* =============================== */
int hamming_distance(
                     register unsigned long *array1,
                     register unsigned long *array2,
                     register int length) {
  register unsigned long diff;   /*bit difference */
  register int dist;             /*total distance */

  dist = 0;
  for (; length > 0; length--) {
    diff = *array1++ ^ *array2++;/*different bits */
    while (diff) {
      diff &= diff - 1;          /*lose a bit */
      dist++;
    }
  }
  return dist;                   /*total distance */
}


/* =============================== */
BIT_VECTOR NewBitVector(int NumBits) { 
  BitVectorCount++;
  return ((BIT_VECTOR) Emalloc (sizeof (unsigned long) *
    WordsInVectorOfSize (NumBits)));

}                                /* NewBitVector */

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