// SPDX-License-Identifier: GPL-2.0-only
/*
 * stdlib functions
 *
 * Author: Scott Wood <scottwood@freescale.com>
 *
 * Copyright (c) 2007 Freescale Semiconductor, Inc.
 */

#include "stdlib.h"

/* Not currently supported: leading whitespace, sign, 0x prefix, zero base */
unsigned long long int strtoull(const char *ptr, char **end, int base)
{
        unsigned long long ret = 0;

        if (base > 36)
                goto out;

        while (*ptr) {
                int digit;

                if (*ptr >= '0' && *ptr <= '9' && *ptr < '0' + base)
                        digit = *ptr - '0';
                else if (*ptr >= 'A' && *ptr < 'A' + base - 10)
                        digit = *ptr - 'A' + 10;
                else if (*ptr >= 'a' && *ptr < 'a' + base - 10)
                        digit = *ptr - 'a' + 10;
                else
                        break;

                ret *= base;
                ret += digit;
                ptr++;
        }

out:
        if (end)
                *end = (char *)ptr;

        return ret;
}