fgetwc.cpp File Reference

#include <corecrt_internal_stdio.h>

Include dependency graph for fgetwc.cpp:

Go to the source code of this file.

Functions
wint_t __cdecl	_fgetwc_nolock (FILE *const public_stream)
wint_t __cdecl	_getwc_nolock (FILE *const stream)
wint_t __cdecl	fgetwc (FILE *const stream)
wint_t __cdecl	getwc (FILE *const stream)
wint_t __cdecl	_fgetwchar ()
wint_t __cdecl	getwchar ()

Function Documentation

_fgetwc_nolock()

wint_t __cdecl _fgetwc_nolock

(

FILE *const

public_stream

)

Definition at line 14 of file fgetwc.cpp.

{
    __crt_stdio_stream const stream(public_stream);
 
    // If the stream is backed by a real file and is open in a Unicode text mode,
    // we need to read two bytes (note that we read two bytes for both UTF-8 and
    // UTF-16 backed streams, since lowio translates UTF-8 to UTF-16 when we read.
    if (!stream.is_string_backed() &&
        _textmode_safe(_fileno(stream.public_stream())) != __crt_lowio_text_mode::ansi)
    {
        wchar_t wc;
 
        // Compose the wide character by reading byte-by-byte from the stream:
        char* const wc_first = reinterpret_cast<char*>(&wc);
        char* const wc_last  = wc_first + sizeof(wc);
 
        for (char* it = wc_first; it != wc_last; ++it)
        {
            int const c = _getc_nolock(stream.public_stream());
            if (c == EOF)
                return WEOF;
 
            *it = static_cast<char>(c);
        }
 
        return wc;
    }
 
    if (!stream.is_string_backed() &&
        (_osfile_safe(_fileno(stream.public_stream())) & FTEXT))
    {
        int size = 1;
        int ch;
        char mbc[4];
        wchar_t wch;
 
        /* text (multi-byte) mode */
        if ((ch = _getc_nolock(stream.public_stream())) == EOF)
            return WEOF;
 
        mbc[0] = static_cast<char>(ch);
 
        if (isleadbyte(static_cast<unsigned char>(mbc[0])))
        {
            if ((ch = _getc_nolock(stream.public_stream())) == EOF)
            {
                ungetc(mbc[0], stream.public_stream());
                return WEOF;
            }
            mbc[1] = static_cast<char>(ch);
            size = 2;
        }
 
        if (mbtowc(&wch, mbc, size) == -1)
        {
            // Conversion failed! Set errno and return failure:
            errno = EILSEQ;
            return WEOF;
        }
 
        return wch;
    }
 
    // binary (Unicode) mode
    if (stream->_cnt >= static_cast<int>(sizeof(wchar_t)))
    {
        stream->_cnt -= static_cast<int>(sizeof(wchar_t));
        return *reinterpret_cast<wchar_t*&>(stream->_ptr)++;
    }
    else
    {
        return static_cast<wint_t>(__acrt_stdio_refill_and_read_wide_nolock(stream.public_stream()));
    }
}

Referenced by _getwc_nolock(), and fgetwc().

_fgetwchar()

wint_t __cdecl _fgetwchar

(

void

)

Definition at line 127 of file fgetwc.cpp.

{
    return fgetwc(stdin);
}

Referenced by getwchar().

_getwc_nolock()

wint_t __cdecl _getwc_nolock

(

FILE *const

stream

)

Definition at line 91 of file fgetwc.cpp.

{
    return _fgetwc_nolock(stream);
}

fgetwc()

wint_t __cdecl fgetwc

(

FILE *const

stream

)

Definition at line 98 of file fgetwc.cpp.

{
    _VALIDATE_RETURN(stream != nullptr, EINVAL, WEOF);
 
    wint_t return_value = 0;
 
    _lock_file(stream);
    __try
    {
        return_value = _fgetwc_nolock(stream);
    }
    __finally
    {
        _unlock_file(stream);
    }
    __endtry
 
    return return_value;
}

Referenced by _fgetwchar(), and getwc().

getwc()

wint_t __cdecl getwc

(

FILE *const

stream

)

Definition at line 120 of file fgetwc.cpp.

{
    return fgetwc(stream);
}

getwchar()

wint_t __cdecl getwchar

(

void

)

Definition at line 134 of file fgetwc.cpp.

{
    return _fgetwchar();
}