1 /* Copyright (C) 1996 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1996.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If
17 not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
28 static mbstate_t internal;
31 mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps)
41 /* See first paragraph of description in 7.16.6.3.2. */
51 unsigned char byte = (unsigned char) *s++;
54 /* We must look for a possible first byte of a UTF8 sequence. */
57 /* One byte sequence. */
59 *pwc = (wchar_t) byte;
60 return byte ? used : 0;
63 if ((byte & 0xc0) == 0x80 || (byte & 0xfe) == 0xfe)
65 /* Oh, oh. An encoding error. */
70 if ((byte & 0xe0) == 0xc0)
72 /* We expect two bytes. */
74 ps->value = byte & 0x1f;
76 else if ((byte & 0xf0) == 0xe0)
78 /* We expect three bytes. */
80 ps->value = byte & 0x0f;
82 else if ((byte & 0xf8) == 0xf0)
84 /* We expect four bytes. */
86 ps->value = byte & 0x07;
88 else if ((byte & 0xfc) == 0xf8)
90 /* We expect five bytes. */
92 ps->value = byte & 0x03;
96 /* We expect six bytes. */
98 ps->value = byte & 0x01;
102 /* We know we have to handle a multibyte character and there are
103 some more bytes to read. */
106 /* The second to sixths byte must be of the form 10xxxxxx. */
107 unsigned char byte = (unsigned char) *s++;
110 if ((byte & 0xc0) != 0x80)
112 /* Oh, oh. An encoding error. */
118 ps->value |= byte & 0x3f;
120 if (--ps->count == 0)
122 /* The character is finished. */
124 *pwc = (wchar_t) ps->value;
125 return ps->value ? used : 0;