#define _POSIX_C_SOURCE 200809L

#include "utils.h"
#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

int getul_n(const char *const s, unsigned long *const out)
{
    char *end;
    unsigned long v;

    errno = 0;
    v = strtoull(s, &end, 10);

    if (errno)
    {
        fprintf(stderr, "%s: strtoul(3) %s: %s\n", __func__, s,
            strerror(errno));
        return -1;
    }
    else if (*end || v > LONG_MAX)
    {
        fprintf(stderr, "%s: invalid number: %.*s\n", __func__,
            (int)(end - s), s);
        return -1;
    }

    *out = v;
    return 0;
}