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
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
/*
Copyright (c) 1990 Regents of the University of California.
All rights reserved.
*/
/*
FUNCTION
<<mbtowc>>---minimal multibyte to wide char converter
INDEX
mbtowc
SYNOPSIS
#include <stdlib.h>
int mbtowc(wchar_t *restrict <[pwc]>, const char *restrict <[s]>, size_t <[n]>);
DESCRIPTION
When _MB_CAPABLE is not defined, this is a minimal ANSI-conforming
implementation of <<mbtowc>>. In this case,
only ``multi-byte character sequences'' recognized are single bytes,
and they are ``converted'' to themselves.
Each call to <<mbtowc>> copies one character from <<*<[s]>>> to
<<*<[pwc]>>>, unless <[s]> is a null pointer. The argument n
is ignored.
When _MB_CAPABLE is defined, this routine uses a state variable to
allow state dependent decoding. The result is based on the locale
setting which may be restricted to a defined set of locales.
RETURNS
This implementation of <<mbtowc>> returns <<0>> if
<[s]> is <<NULL>> or is the empty string;
it returns <<1>> if not _MB_CAPABLE or
the character is a single-byte character; it returns <<-1>>
if n is <<0>> or the multi-byte character is invalid;
otherwise it returns the number of bytes in the multibyte character.
If the return value is -1, no changes are made to the <<pwc>>
output string. If the input is the empty string, a wchar_t nul
is placed in the output string and 0 is returned. If the input
has a length of 0, no changes are made to the <<pwc>> output string.
PORTABILITY
<<mbtowc>> is required in the ANSI C standard. However, the precise
effects vary with the locale.
<<mbtowc>> requires no supporting OS subroutines.
*/
#ifndef _REENT_ONLY
#include <newlib.h>
#include <stdlib.h>
#include <wchar.h>
#include "local.h"
int
mbtowc (wchar_t *__restrict pwc,
const char *__restrict s,
size_t n)
{
#ifdef _MB_CAPABLE
int retval = 0;
static NEWLIB_THREAD_LOCAL mbstate_t _mbtowc_state;
retval = __MBTOWC (pwc, s, n, &_mbtowc_state);
if (retval < 0)
{
_mbtowc_state.__count = 0;
return -1;
}
return retval;
#else /* not _MB_CAPABLE */
if (s == NULL)
return 0;
if (n == 0)
return -1;
if (pwc)
*pwc = (wchar_t) *s;
return (*s != '\0');
#endif /* not _MB_CAPABLE */
}
#endif /* !_REENT_ONLY */
|
