| 1 | /* |
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| 2 | FUNCTION |
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| 3 | <<mbtowc>>---minimal multibyte to wide char converter |
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| 4 | |
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| 5 | INDEX |
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| 6 | mbtowc |
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| 7 | |
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| 8 | SYNOPSIS |
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| 9 | #include <stdlib.h> |
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| 10 | int mbtowc(wchar_t *restrict <[pwc]>, const char *restrict <[s]>, size_t <[n]>); |
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| 11 | |
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| 12 | DESCRIPTION |
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| 13 | When _MB_CAPABLE is not defined, this is a minimal ANSI-conforming |
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| 14 | implementation of <<mbtowc>>. In this case, |
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| 15 | only ``multi-byte character sequences'' recognized are single bytes, |
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| 16 | and they are ``converted'' to themselves. |
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| 17 | Each call to <<mbtowc>> copies one character from <<*<[s]>>> to |
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| 18 | <<*<[pwc]>>>, unless <[s]> is a null pointer. The argument n |
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| 19 | is ignored. |
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| 20 | |
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| 21 | When _MB_CAPABLE is defined, this routine calls <<_mbtowc_r>> to perform |
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| 22 | the conversion, passing a state variable to allow state dependent |
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| 23 | decoding. The result is based on the locale setting which may |
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| 24 | be restricted to a defined set of locales. |
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| 25 | |
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| 26 | RETURNS |
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| 27 | This implementation of <<mbtowc>> returns <<0>> if |
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| 28 | <[s]> is <<NULL>> or is the empty string; |
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| 29 | it returns <<1>> if not _MB_CAPABLE or |
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| 30 | the character is a single-byte character; it returns <<-1>> |
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| 31 | if n is <<0>> or the multi-byte character is invalid; |
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| 32 | otherwise it returns the number of bytes in the multibyte character. |
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| 33 | If the return value is -1, no changes are made to the <<pwc>> |
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| 34 | output string. If the input is the empty string, a wchar_t nul |
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| 35 | is placed in the output string and 0 is returned. If the input |
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| 36 | has a length of 0, no changes are made to the <<pwc>> output string. |
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| 37 | |
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| 38 | PORTABILITY |
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| 39 | <<mbtowc>> is required in the ANSI C standard. However, the precise |
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| 40 | effects vary with the locale. |
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| 41 | |
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| 42 | <<mbtowc>> requires no supporting OS subroutines. |
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| 43 | */ |
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| 44 | |
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| 45 | #ifndef _REENT_ONLY |
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| 46 | |
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| 47 | #include <newlib.h> |
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| 48 | #include <stdlib.h> |
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| 49 | #include <wchar.h> |
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| 50 | #include "local.h" |
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| 51 | |
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| 52 | int |
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| 53 | mbtowc (wchar_t *__restrict pwc, |
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| 54 | const char *__restrict s, |
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| 55 | size_t n) |
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| 56 | { |
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| 57 | #ifdef _MB_CAPABLE |
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| 58 | int retval = 0; |
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| 59 | struct _reent *reent = _REENT; |
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| 60 | mbstate_t *ps; |
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| 61 | |
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| 62 | _REENT_CHECK_MISC(reent); |
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| 63 | ps = &(_REENT_MBTOWC_STATE(reent)); |
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| 64 | |
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| 65 | retval = __MBTOWC (reent, pwc, s, n, ps); |
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| 66 | |
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| 67 | if (retval < 0) |
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| 68 | { |
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| 69 | ps->__count = 0; |
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| 70 | return -1; |
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| 71 | } |
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| 72 | return retval; |
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| 73 | #else /* not _MB_CAPABLE */ |
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| 74 | if (s == NULL) |
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| 75 | return 0; |
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| 76 | if (n == 0) |
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| 77 | return -1; |
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| 78 | if (pwc) |
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| 79 | *pwc = (wchar_t) *s; |
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| 80 | return (*s != '\0'); |
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| 81 | #endif /* not _MB_CAPABLE */ |
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| 82 | } |
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| 83 | |
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| 84 | #endif /* !_REENT_ONLY */ |
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| 85 | |
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| 86 | |
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| 87 | |
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| 88 | |
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