lib/sh/shmbchar.c

   1 /* Copyright (C) 2001, 2006, 2009, 2010 Free Software Foundation, Inc.
   2
   3    This program is free software: you can redistribute it and/or modify
   4    it under the terms of the GNU General Public License as published by
   5    the Free Software Foundation; either version 3 of the License, or
   6    (at your option) any later version.
   7
   8    This program is distributed in the hope that it will be useful,
   9    but WITHOUT ANY WARRANTY; without even the implied warranty of
  10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11    GNU General Public License for more details.
  12
  13    You should have received a copy of the GNU General Public License
  14    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  15
  16
  17 #include <config.h>
  18
  19 #if defined (HANDLE_MULTIBYTE)
  20 #include <stdlib.h>
  21 #include <limits.h>
  22
  23 #include <shmbutil.h>
  24 #include <shmbchar.h>
  25
  26 #if IS_BASIC_ASCII
  27
  28 /* Bit table of characters in the ISO C "basic character set".  */
  29 const unsigned int is_basic_table [UCHAR_MAX / 32 + 1] =
  30 {
  31   0x00001a00,           /* '\t' '\v' '\f' */
  32   0xffffffef,           /* ' '...'#' '%'...'?' */
  33   0xfffffffe,           /* 'A'...'Z' '[' '\\' ']' '^' '_' */
  34   0x7ffffffe            /* 'a'...'z' '{' '|' '}' '~' */
  35   /* The remaining bits are 0.  */
  36 };
  37
  38 #endif /* IS_BASIC_ASCII */
  39
  40 size_t
  41 mbstrlen (s)
  42      const char *s;
  43 {
  44   size_t clen, nc;
  45   mbstate_t mbs = { 0 }, mbsbak = { 0 };
  46   int f;
  47
  48   nc = 0;
  49   while (*s && (clen = (f = is_basic (*s)) ? 1 : mbrlen(s, MB_CUR_MAX, &mbs)) != 0)
  50     {
  51       if (MB_INVALIDCH(clen))
  52         {
  53           clen = 1;     /* assume single byte */
  54           mbs = mbsbak;
  55         }
  56
  57       if (f == 0)
  58         mbsbak = mbs;
  59
  60       s += clen;
  61       nc++;
  62     }
  63   return nc;
  64 }
  65
  66 /* Return pointer to first multibyte char in S, or NULL if none. */
  67 char *
  68 mbsmbchar (s)
  69      const char *s;
  70 {
  71   char *t;
  72   size_t clen;
  73   mbstate_t mbs = { 0 };
  74
  75   for (t = (char *)s; *t; t++)
  76     {
  77       if (is_basic (*t))
  78         continue;
  79
  80       clen = mbrlen (t, MB_CUR_MAX, &mbs);
  81
  82       if (clen == 0)
  83         return 0;
  84       if (MB_INVALIDCH(clen))
  85         continue;
  86
  87       if (clen > 1)
  88         return t;
  89     }
  90   return 0;
  91 }
  92 #endif