/* File: genselect.c

   A generic selection sort function.
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>   /* for bcopy() */
#include "genselect.h"


void SelectionSort(void *A, int n, int size, CMP_FUNC cmp) {
   int i, j ;
   char *ptr, *iptr,  *jptr, *temp ;

   temp = malloc(size) ;
   if (temp == NULL) {
      fprintf(stderr, "Oops\n") ;
      exit(1) ;
   }

   ptr = (char *) A ;

   for (i=0 ; i < n ; i++) {
      iptr = ptr + i*size ;

      /* Find "largest" element in the remaining array and put in A[i]
      */
      for (j = i+1 ; j < n ; j++) {
         jptr = ptr + j*size ;

         if (cmp(iptr, jptr) < 0) {
            bcopy(iptr, temp, size) ; // copy size bytes from iptr to temp
            bcopy(jptr, iptr, size) ; // copy size bytes from jptr to iptr
            bcopy(temp, jptr, size) ; // copy size bytes from temp to jptr
         }
      }
   }

}