stdlib.c

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/*
 * stdlib functions
 *
 * Author: Scott Wood <[email protected]>
 *
 * Copyright (c) 2007 Freescale Semiconductor, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 */

#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;
}