/*
 * callqsort.c - a version of sortfile() which uses a good sort algorithm by
 *               calling the qsort() C library routine.
 *
 * Alan J Rosenthal, November 2000.
 */

#include <stdio.h>
#include <stdlib.h>

#define MAXNUMS 100


void sortfile(FILE *in, FILE *out)
{
    int a[MAXNUMS + 1], size, i;
    extern void sort(int *a, int size);

    /*
     * Read ints from "in", up to array limit or eof.
     * The assignment handout says it's ok to mistake non-numeric for EOF.
     * The array is one too big so that we can easily see if there are more
     * ints after.
     */
    for (size = 0;
	    size < sizeof a / sizeof a[0] && fscanf(in, "%d", &a[size]) == 1;
	    size++)
	;
    /* if we hit array limit, i.e. have exceeded MAXNUMS, then crab & exit */
    if (size > MAXNUMS) {
	fprintf(stderr, "limit of %d values exceeded\n", MAXNUMS);
	exit(1);
    }

    /* sort and output */
    sort(a, size);
    for (i = 0; i < size; i++)
	fprintf(out, "%d\n", a[i]);
}


/* call qsort to do the sorting */
void sort(int *a, int size)
{
    extern int comparator(const void *p, const void *q);
    qsort((void *)a, size, sizeof(int), comparator);
}


int comparator(const void *p, const void *q)
{
    return *(int *)p - *(int *)q;
}