linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 *  linux/lib/string.c

 *

 *  Copyright (C) 1991, 1992  Linus Torvalds

 */

​

/*

 * stupid library routines.. The optimized versions should generally be found

 * as inline code in <asm-xx/string.h>

 *

 * These are buggy as well..

 *

 * * Fri Jun 25 1999, Ingo Oeser <ioe@informatik.tu-chemnitz.de>

 * -  Added strsep() which will replace strtok() soon (because strsep() is

 *    reentrant and should be faster). Use only strsep() in new code, please.

 *

 * * Sat Feb 09 2002, Jason Thomas <jason@topic.com.au>,

 *                    Matthew Hawkins <matt@mh.dropbear.id.au>

 * -  Kissed strtok() goodbye

 */

​

#include <linux/types.h>

#include <linux/string.h>

#include <linux/ctype.h>

#include <linux/kernel.h>

#include <linux/export.h>

#include <linux/bug.h>

#include <linux/errno.h>

#include <linux/slab.h>

​

#include <asm/byteorder.h>

#include <asm/word-at-a-time.h>

#include <asm/page.h>

​

#ifndef __HAVE_ARCH_STRNCASECMP

/**

 * strncasecmp - Case insensitive, length-limited string comparison

 * @s1: One string

 * @s2: The other string

 * @len: the maximum number of characters to compare

 */

int strncasecmp(const char *s1, const char *s2, size_t len)

{

    /* Yes, Virginia, it had better be unsigned */

    unsigned char c1, c2;

​

    if (!len)

        return 0;

​

    do {

        c1 = *s1++;

        c2 = *s2++;

        if (!c1 || !c2)

            break;

        if (c1 == c2)

            continue;

        c1 = tolower(c1);

        c2 = tolower(c2);

        if (c1 != c2)

            break;

    } while (--len);

    return (int)c1 - (int)c2;