usr/src/lib/libcurses/screen/mbtowc.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 2008 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*  Copyright (c) 1988 AT&T */
  28 /*    All Rights Reserved   */
  29
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31
  32 #include <widec.h>
  33 #include <ctype.h>
  34 #include <sys/types.h>
  35 #include "curses_wchar.h"
  36
  37 int
  38 _curs_mbtowc(wchar_t *wchar, const char *s, size_t n)
  39 {
  40         int length, c;
  41         wchar_t intcode;
  42         char *olds = (char *)s;
  43         wchar_t mask;
  44
  45         if (s == (char *)0)
  46                 return (0);
  47         if (n == 0)
  48                 return (-1);
  49         c = (unsigned char)*s++;
  50         if (c < 0200) {
  51                 if (wchar)
  52                         *wchar = c;
  53                 return (c ? 1 : 0);
  54         }
  55         intcode = 0;
  56         if (c == SS2) {
  57                 if ((length = eucw2) == 0)
  58                         goto lab1;
  59                 mask = P01;
  60                 goto lab2;
  61         } else if (c == SS3) {
  62                 if ((length = eucw3) == 0)
  63                         goto lab1;
  64                 mask = P10;
  65                 goto lab2;
  66         }
  67 lab1:
  68         if (iscntrl(c)) {
  69                 if (wchar)
  70                         *wchar = c;
  71                 return (1);
  72         }
  73         length = eucw1 - 1;
  74         mask = P11;
  75         intcode = c & 0177;
  76 lab2:
  77         if (length + 1 > n || length < 0)
  78                 return (-1);
  79         while (length--) {
  80                 if ((c = (unsigned char)*s++) < 0200 || iscntrl(c))
  81                         return (-1);
  82                 intcode = (intcode << 7) | (c & 0x7F);
  83         }
  84         if (wchar)
  85                 *wchar = intcode | mask;
  86         /*LINTED*/
  87         return ((int)(s - olds));
  88 }