usr/src/lib/libc/port/locale/strncasecmp.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2013 Garrett D'Amore <garrett@damore.org>
  24  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
  25  */
  26
  27 /*      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T     */
  28 /*        All Rights Reserved   */
  29
  30 /*
  31  * Portions of this source code were derived from Berkeley 4.3 BSD
  32  * under license from the Regents of the University of California.
  33  */
  34
  35 #include "lint.h"
  36 #include <sys/types.h>
  37 #include <strings.h>
  38 #include <ctype.h>
  39 #include <locale.h>
  40 #include "lctype.h"
  41 #include "localeimpl.h"
  42
  43 int
  44 strncasecmp_l(const char *s1, const char *s2, size_t n, locale_t loc)
  45 {
  46         extern int ascii_strncasecmp(const char *s1, const char *s2, size_t n);
  47         const int *cm;
  48         const uchar_t *us1;
  49         const uchar_t *us2;
  50         const struct lc_ctype *lct = loc->ctype;
  51
  52         /*
  53          * If we are in a locale that uses the ASCII character set
  54          * (C or POSIX), use the fast ascii_strncasecmp() function.
  55          */
  56         if (lct->lc_is_ascii)
  57                 return (ascii_strncasecmp(s1, s2, n));
  58
  59         cm = lct->lc_trans_lower;
  60         us1 = (const uchar_t *)s1;
  61         us2 = (const uchar_t *)s2;
  62
  63         while (n != 0 && cm[*us1] == cm[*us2++]) {
  64                 if (*us1++ == '\0')
  65                         return (0);
  66                 n--;
  67         }
  68         return (n == 0 ? 0 : cm[*us1] - cm[*(us2 - 1)]);
  69 }
  70
  71 int
  72 strncasecmp(const char *s1, const char *s2, size_t n)
  73 {
  74         return (strncasecmp_l(s1, s2, n, uselocale(NULL)));
  75 }