/*-

 * Copyright (c) 1990, 1993

 *	The Regents of the University of California.  All rights reserved.

 *

 * This code is derived from software contributed to Berkeley by

 * Chris Torek.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 4. Neither the name of the University nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 */

#if defined(LIBC_SCCS) && !defined(lint)

static char sccsid[] = "@(#)wsetup.c	8.1 (Berkeley) 6/4/93";

#endif /* LIBC_SCCS and not lint */

#include <sys/cdefs.h>

__FBSDID("$FreeBSD: src/lib/libc/stdio/wsetup.c,v 1.9 2004/06/08 05:44:52 das Exp $");

#include <errno.h>

#include <stdio.h>

#include <stdlib.h>

#include "local.h"

#if (defined(__SYMBIAN32__) && (defined(__WINSCW__) || defined(__WINS__)))

#include "libc_wsd_defs.h"

#endif

#ifdef EMULATOR

int *GET_WSD_VAR_NAME(__sdidinit, g)();

#define __sdidinit (*GET_WSD_VAR_NAME(__sdidinit, g)())

#endif //EMULATOR

/*

 * Various output routines call wsetup to be sure it is safe to write,

 * because either _flags does not include __SWR, or _buf is NULL.

 * _wsetup returns 0 if OK to write; otherwise, it returns EOF and sets errno.

 */

int

__swsetup(fp)

	FILE *fp;

{

	/* make sure stdio is set up */

	if (!__sdidinit)

		__sinit();

	/*

	 * If we are not writing, we had better be reading and writing.

	 */

	if ((fp->_flags & __SWR) == 0) {

		if ((fp->_flags & __SRW) == 0) {

			errno = EBADF;

#ifdef __SYMBIAN32__

			fp->_flags |= __SERR;

#endif			

			return (EOF);

		}

		if (fp->_flags & __SRD) {

			/* clobber any ungetc data */

			if (HASUB(fp))

				FREEUB(fp);

			fp->_flags &= ~(__SRD|__SEOF);

			/*   Need to adjust the real-byte offset of the file

			 *   depending on the value of fp->_r 

			 *   before resetting its value.

			 *   In binary-mode: seekBackCount = No. of unread bytes in buffer

			 *   In text-mode: seekBackCount = (No. of unread chars in buffer + No. of newlines present as part of unread chars in buffer)

			 */

			if(fp->_r)

			    {

	            fpos_t offset = 0;

	            /* Count newlines present as part of unread characters

	             * in buffer denoted by ( fp->_r ) only in text-mode

	             */ 

	            if( fp->_extra->fmode == 't')

	                {

	                int newlines = 0, len = 0;

	                char *p = NULL;

	                p = (char*)(fp->_p);

	                while( len++ < fp->_r )

	                    {

	                    if( *p++ == '\n' )

	                        newlines++;

	                    }

	                offset += newlines;

	                }

	            offset += fp->_r;  

			    if( (_sseek(fp, -(fpos_t)offset, SEEK_CUR)) == (-(fpos_t)1) )

			        return (-1);

			    }

			fp->_r = 0;

			fp->_p = fp->_bf._base;

		}

		fp->_flags |= __SWR;

	}

	/*

	 * Make a buffer if necessary, then set _w.

	 */

	if (fp->_bf._base == NULL)

	{

		__smakebuf(fp);

		if(fp->_bf._base == NULL && errno == ENOMEM)

		{

			return (EOF);

		}

	}

	if (fp->_flags & __SLBF) {

		/*

		 * It is line buffered, so make _lbfsize be -_bufsize

		 * for the putc() macro.  We will change _lbfsize back

		 * to 0 whenever we turn off __SWR.

		 */

		fp->_w = 0;

		fp->_lbfsize = -fp->_bf._size;

	} else

		fp->_w = fp->_flags & __SNBF ? 0 : fp->_bf._size;

	return (0);

}