1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
|
/* Test for initial conversion state.
Copyright (C) 2008-2020 Free Software Foundation, Inc.
Written by Bruno Haible <bruno@clisp.org>, 2008.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
#include <config.h>
/* Specification. */
#include <wchar.h>
#include "verify.h"
#if GNULIB_defined_mbstate_t
/* Platforms that lack mbsinit() also lack mbrlen(), mbrtowc(), mbsrtowcs()
and wcrtomb(), wcsrtombs().
We assume that
- sizeof (mbstate_t) >= 4,
- only stateless encodings are supported (such as UTF-8 and EUC-JP, but
not ISO-2022 variants),
- for each encoding, the number of bytes for a wide character is <= 4.
(This maximum is attained for UTF-8, GB18030, EUC-TW.)
We define the meaning of mbstate_t as follows:
- In mb -> wc direction, mbstate_t's first byte contains the number of
buffered bytes (in the range 0..3), followed by up to 3 buffered bytes.
See mbrtowc.c.
- In wc -> mb direction, mbstate_t contains no information. In other
words, it is always in the initial state. */
verify (sizeof (mbstate_t) >= 4);
int
mbsinit (const mbstate_t *ps)
{
const char *pstate = (const char *)ps;
return pstate == NULL || pstate[0] == 0;
}
#else
int
mbsinit (const mbstate_t *ps)
{
# if defined _WIN32 && !defined __CYGWIN__
/* Native Windows. */
/* MSVC defines 'mbstate_t' as an 8-byte struct; the first 4 bytes matter.
On mingw, 'mbstate_t' is sometimes defined as 'int', sometimes defined as
an 8-byte struct, of which the first 4 bytes matter. */
return ps == NULL || *(const unsigned int *)ps == 0;
# else
/* Minix, HP-UX 11.00, Solaris 2.6, Interix, ... */
/* Maybe this definition works, maybe not... */
return ps == NULL || *(const char *)ps == 0;
# endif
}
#endif
|