port/stdio/_flsbuf.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1988 AT&T */
/*    All Rights Reserved   */

#pragma ident   "%Z%%M% %I% %E% SMI"

#pragma weak __flsbuf = _flsbuf

#include "lint.h"
#include "file64.h"
#include <mtlib.h>
#include <stdio.h>
#include <thread.h>
#include <synch.h>
#include <unistd.h>
#include <sys/types.h>
#include "stdiom.h"

int
_flsbuf(int ch, FILE *iop)  /* flush (write) buffer, save ch, */
                /* return EOF on failure */
{
    Uchar uch;

    do  /* only loop if need to use _wrtchk() on non-_IOFBF */
    {
        switch (iop->_flag & (_IOFBF | _IOLBF | _IONBF |
                _IOWRT | _IOEOF))
        {
        case _IOFBF | _IOWRT:   /* okay to do full-buffered case */
            if (iop->_base != 0 && iop->_ptr > iop->_base)
                goto flush_putc;    /* skip _wrtchk() */
            break;
        case _IOLBF | _IOWRT:   /* okay to do line-buffered case */
            if (iop->_ptr >= _bufend(iop))
                /*
                 * which will recursively call
                 * __flsbuf via putc because of no room
                 * in the buffer for the character
                 */
                goto flush_putc;
            if ((*iop->_ptr++ = (unsigned char)ch) == '\n')
                (void) _xflsbuf(iop);
            iop->_cnt = 0;
            goto out;
        case _IONBF | _IOWRT:   /* okay to do no-buffered case */
            iop->_cnt = 0;
            uch = (unsigned char)ch;
            if (write(GET_FD(iop), (char *)&uch, 1) != 1) {
                if (!cancel_active())
                    iop->_flag |= _IOERR;
                return (EOF);
            }
            goto out;
        }
        if (_wrtchk(iop) != 0)  /* check, correct permissions */
            return (EOF);
    } while (iop->_flag & (_IOLBF | _IONBF));
flush_putc:
    (void) _xflsbuf(iop);
    (void) PUTC(ch, iop); /*  recursive call */
out:
    /* necessary for putc() */
    return ((iop->_flag & _IOERR) ? EOF : (unsigned char)ch);
}