/*
 * nanobbs, a tiny forums software.
 * Copyright (C) 2025-2026  Xavier Del Campo Romero
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

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

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

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

    *out = v;
    *s = *end ? end + 1 : end;
    return 0;
}