locale/mbrune.c

   1 /*-
   2  * Copyright (c) 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Paul Borman at Krystal Technologies.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by the University of
  19  *      California, Berkeley and its contributors.
  20  * 4. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  */
  36
  37 #if defined(LIBC_SCCS) && !defined(lint)
  38 static char sccsid[] = "@(#)mbrune.c    8.1 (Berkeley) 6/27/93";
  39 #endif /* LIBC_SCCS and not lint */
  40
  41 #include <limits.h>
  42 #include <rune.h>
  43 #include <stddef.h>
  44 #include <string.h>
  45
  46 char *
  47 mbrune(string, c)
  48         const char *string;
  49         rune_t c;
  50 {
  51         char const *result;
  52         rune_t r;
  53
  54         while ((r = sgetrune(string, MB_LEN_MAX, &result))) {
  55                 if (r == c)
  56                         return ((char *)string);
  57                 string = result == string ? string + 1 : result;
  58         }
  59
  60         return (c == *string ? (char *)string : NULL);
  61 }
  62
  63 char *
  64 mbrrune(string, c)
  65         const char *string;
  66         rune_t c;
  67 {
  68         const char *last = 0;
  69         char const *result;
  70         rune_t  r;
  71
  72         while ((r = sgetrune(string, MB_LEN_MAX, &result))) {
  73                 if (r == c)
  74                         last = string;
  75                 string = result == string ? string + 1 : result;
  76         }
  77         return (c == *string ? (char *)string : (char *)last);
  78 }
  79
  80 char *
  81 mbmb(string, pattern)
  82         const char *string;
  83         char *pattern;
  84 {
  85         rune_t first, r;
  86         size_t plen, slen;
  87         char const *result;
  88
  89         plen = strlen(pattern);
  90         slen = strlen(string);
  91         if (plen > slen)
  92                 return (0);
  93
  94         first = sgetrune(pattern, plen, &result);
  95         if (result == string)
  96                 return (0);
  97
  98         while (slen >= plen && (r = sgetrune(string, slen, &result))) {
  99                 if (r == first) {
 100                         if (strncmp(string, pattern, slen) == 0)
 101                                 return ((char *) string);
 102                 }
 103                 if (result == string) {
 104                         --slen;
 105                         ++string;
 106                 } else {
 107                         slen -= result - string;
 108                         string = result;
 109                 }
 110         }
 111         return (0);
 112 }