istrget.cpp

C标准库源代码

/***
* istrget.cpp - definitions for istream class get() member functions
*
*       Copyright (c) 1991-1997, Microsoft Corporation.  All rights reserved.
*
*Purpose:
*       Definitions of get() member functions for istream class.
*       [AT&T C++]
*
*******************************************************************************/

#include <cruntime.h>
#include <internal.h>
#include <iostream.h>
#pragma hdrstop

// unformatted input functions

int istream::get()
{
    int c;
    if (ipfx(1))        // resets x_gcount
        {
        if ((c=bp->sbumpc())==EOF)
            state |= ios::eofbit;
        else
            x_gcount++;
        isfx();
        return c;
        }
    return EOF;
}

// signed and unsigned char make inline calls to this:
istream& istream::get( char& c)
{
    int temp;
    if (ipfx(1))        // resets x_gcount
        {
        if ((temp=bp->sbumpc())==EOF)
            state |= (ios::failbit|ios::eofbit);
        else
            x_gcount++;
        c = (char) temp;
        isfx();
        }
    return *this;
}


// called by signed and unsigned char versions
istream& istream::read(char * ptr, int n)
{
    if (ipfx(1))        // resets x_gcount
        {
        x_gcount = bp->sgetn(ptr, n);
        if ((unsigned)x_gcount < (unsigned)n)
            state |= (ios::failbit|ios::eofbit);
        isfx();
        }
    return *this;
}