locale/FreeBSD/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
  27 #include <sys/cdefs.h>
  28 __FBSDID("$FreeBSD: src/lib/libc/locale/fix_grouping.c,v 1.8 2003/06/26 10:46:16 phantom Exp $");
  29
  30 #include <ctype.h>
  31 #include <limits.h>
  32 #include <stddef.h>
  33
  34 static const char nogrouping[] = { '\0' };
  35 static const char __nogrouping[] = { CHAR_MAX, '\0' };
  36
  37 /*
  38  * Internal helper used to convert grouping sequences from string
  39  * representation into POSIX specified form, i.e.
  40  *
  41  * "3;3;-1" -> "\003\003\177\000"
  42  */
  43
  44 const char *
  45 __fix_locale_grouping_str(const char *str)
  46 {
  47         char *src, *dst;
  48         char n;
  49
  50         if (str == NULL || *str == '\0') {
  51                 return nogrouping;
  52         }
  53
  54         for (src = (char*)str, dst = (char*)str; *src != '\0'; src++) {
  55
  56                 /* input string examples: "3;3", "3;2;-1" */
  57                 if (*src == ';')
  58                         continue;
  59
  60                 if (*src == '-' && *(src+1) == '1') {
  61                         *dst++ = CHAR_MAX;
  62                         src++;
  63                         continue;
  64                 }
  65
  66                 if (!isdigit((unsigned char)*src)) {
  67                         /* broken grouping string */
  68                         return nogrouping;
  69                 }
  70
  71                 /* assume all numbers <= 99 */
  72                 n = *src - '0';
  73                 if (isdigit((unsigned char)*(src+1))) {
  74                         src++;
  75                         n *= 10;
  76                         n += *src - '0';
  77                 }
  78
  79                 *dst = n;
  80                 /* NOTE: assume all input started with "0" as 'no grouping' */
  81                 if (*dst == '\0')
  82                         return (dst == (char*)str) ? nogrouping : str;
  83                 dst++;
  84         }
  85         *dst = '\0';
  86         return str;
  87 }
  88
  89 /*
  90  * internal helpers for SUSv3 compatibility.  Since "nogrouping" needs to
  91  * be just an empty string, we provide a routine to substitute __nogrouping
  92  * so we don't have to modify code that expects CHAR_MAX.
  93  */
  94 __private_extern__ const char *
  95 __fix_nogrouping(const char *str)
  96 {
  97         return ((str == NULL || *str == '\0') ? __nogrouping : str);
  98 }