glue-strcasecmp.c

/*
 * Copyright (c) 2008-2014, Pedigree Developers
 *
 * Please see the CONTRIB file in the root of the source tree for a full
 * list of contributors.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "newlib.h"

#include <stdint.h>
#include <wctype.h>

int strcasecmp(const char *s1, const char *s2)
{
    if (!(s1 && s2))
        return 0;  // Same, but NULL.

    int r = 0;
    while (*s1)
    {
        wchar_t c1, c2;
        int s1_stride = mbtowc(&c1, s1, 6);
        int s2_stride = mbtowc(&c2, s2, 6);
        r = towlower(c1) - towlower(c2);
        if (r)
            goto done;
        s1 += s1_stride;
        s2 += s2_stride;
    }

    if (*s1 && !*s2)
        r = -1;
    else if (!*s1 && *s2)
        r = 1;

done:
    return r;
}