/* glibc quick sort test originally by Qualys, enhanced for Rocky Linux */

#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <sys/resource.h>

static int
cmp(const void * const pa, const void * const pb)
{
    const int a = *(const int *)pa;
    const int b = *(const int *)pb;
    return (a - b);
}

int
main(const int argc, const char * const argv[])
{
    if (argc != 2) return __LINE__;
    const size_t nmemb = strtoul(argv[1], NULL, 0);
    if (nmemb <= 0 || nmemb >= (1<<28)) return __LINE__;

    int * const pcanary1 = calloc(1 + nmemb + 1, sizeof(int));
    if (!pcanary1) return __LINE__;
    int * const array = pcanary1 + 1;
    int * const pcanary2 = array + nmemb;

    struct timeval tv;
    if (gettimeofday(&tv, NULL)) return __LINE__;
    srandom((tv.tv_sec << 16) ^ tv.tv_usec);

    const int canary1 = *pcanary1 = (random() << 16) ^ random();
    const int canary2 = *pcanary2 = (random() << 16) ^ random();
    array[random() % nmemb] = INT_MIN;

    /* Force fallback from merge to quick sort */
    const struct rlimit rlim = {};
    setrlimit(RLIMIT_AS, &rlim);

    qsort(array, nmemb, sizeof(int), cmp);
    if (*pcanary1 != canary1) abort();
    if (*pcanary2 != canary2) abort();

    for (size_t i = 0; i < nmemb; i++)
        array[i] = random();

    qsort(array, nmemb, sizeof(int), cmp);
    if (*pcanary1 != canary1) abort();
    if (*pcanary2 != canary2) abort();

    for (size_t i = 1; i < nmemb; i++)
        if (array[i - 1] > array[i]) abort();

    puts("PASSED");

    return 0;
}