fgets.cpp File Reference

#include <corecrt_internal_stdio.h>

Include dependency graph for fgets.cpp:

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Functions
template<typename Character >
	_Success_ (return !=0) static Character *__cdecl common_fgets(_Out_writes_z_(count) Character *const string
int const __crt_stdio_stream const stream	throw ()
char *__cdecl	fgets (char *const string, int const count, FILE *const stream)
wchar_t *__cdecl	fgetws (wchar_t *const string, int const count, FILE *const stream)

Variables
int const	count

Function Documentation

_Success_()

template<typename Character >

_Success_

(

return !

= 0

)

const

fgets()

char *__cdecl fgets	(	char *const	string,
		int const	count,
		FILE *const	stream
	)

Definition at line 85 of file fgets.cpp.

{
    return common_fgets(string, count, __crt_stdio_stream(stream));
}

fgetws()

wchar_t *__cdecl fgetws	(	wchar_t *const	string,
		int const	count,
		FILE *const	stream
	)

Definition at line 94 of file fgets.cpp.

{
    return common_fgets(string, count, __crt_stdio_stream(stream));
}

throw()

int const __crt_stdio_stream const stream throw

(

)

Definition at line 27 of file fgets.cpp.

{
    typedef __acrt_stdio_char_traits<Character> stdio_traits;
 
    _VALIDATE_RETURN(string != nullptr || count == 0, EINVAL, nullptr);
    _VALIDATE_RETURN(count >= 0,                      EINVAL, nullptr);
    _VALIDATE_RETURN(stream.valid(),                  EINVAL, nullptr);
 
    if (count == 0)
        return nullptr;
 
    Character* return_value = nullptr;
 
    _lock_file(stream.public_stream());
    __try
    {
        if (!stdio_traits::validate_stream_is_ansi_if_required(stream.public_stream()))
            __leave;
 
        // Note that we start iterating at 1, so we read at most 'count - 1'
        // characters from the stream, leaving room for the null terminator:
        Character* it = string;
        for (int i = 1; i != count; ++i)
        {
            int const c = stdio_traits::getc_nolock(stream.public_stream());
            if (c == stdio_traits::eof)
            {
                // If we immediately reach EOF before reading any characters,
                // the C Language Standard mandates that the input buffer should
                // be left unmodified, so we return immediately, without writing
                // anything to the buffer:
                if (it == string)
                    __leave;
 
                // Otherwise, when we reach EOF, we just need to stop iterating:
                break;
            }
 
            // We stop reading when we reach a newline.  We do copy the newline:
            *it++ = static_cast<Character>(c);
            if (static_cast<Character>(c) == '\n')
                break;
        }
 
        *it = '\0';
        return_value = string;
    }
    __finally
    {
        _unlock_file(stream.public_stream());
    }
    __endtry
 
    return return_value;
}

Variable Documentation

count

int const count

Definition at line 25 of file fgets.cpp.

Referenced by throw().