lib/libc/locale/fix_grouping.c

   1 /*
   2  * Copyright (c) 2001 Alexey Zelkin <phantom@FreeBSD.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: head/lib/libc/locale/fix_grouping.c 116875 2003-06-26 10:46:16Z phantom $
  27  */
  28
  29
  30 #include <ctype.h>
  31 #include <limits.h>
  32 #include <stddef.h>
  33
  34 static const char nogrouping[] = { CHAR_MAX, '\0' };
  35
  36 /*
  37  * Internal helper used to convert grouping sequences from string
  38  * representation into POSIX specified form, i.e.
  39  *
  40  * "3;3;-1" -> "\003\003\177\000"
  41  */
  42
  43 const char *
  44 __fix_locale_grouping_str(const char *str)
  45 {
  46         char *src, *dst;
  47         char n;
  48
  49         if (str == NULL || *str == '\0') {
  50                 return nogrouping;
  51         }
  52
  53         for (src = (char*)str, dst = (char*)str; *src != '\0'; src++) {
  54
  55                 /* input string examples: "3;3", "3;2;-1" */
  56                 if (*src == ';')
  57                         continue;
  58
  59                 if (*src == '-' && *(src+1) == '1') {
  60                         *dst++ = CHAR_MAX;
  61                         src++;
  62                         continue;
  63                 }
  64
  65                 if (!isdigit((unsigned char)*src)) {
  66                         /* broken grouping string */
  67                         return nogrouping;
  68                 }
  69
  70                 /* assume all numbers <= 99 */
  71                 n = *src - '0';
  72                 if (isdigit((unsigned char)*(src+1))) {
  73                         src++;
  74                         n *= 10;
  75                         n += *src - '0';
  76                 }
  77
  78                 *dst = n;
  79                 /* NOTE: assume all input started with "0" as 'no grouping' */
  80                 if (*dst == '\0')
  81                         return (dst == (char*)str) ? nogrouping : str;
  82                 dst++;
  83         }
  84         *dst = '\0';
  85         return str;
  86 }