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/*
* 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 */
/*
* Return file offset.
* Coordinates with buffering.
*/
#pragma weak _ftell = ftell
#include "lint.h"
#include "file64.h"
#include "mtlib.h"
#include <fcntl.h>
#include <stdio.h>
#include <thread.h>
#include <synch.h>
#include <errno.h>
#include <unistd.h>
#include <stddef.h>
#include <limits.h>
#include <sys/types.h>
#include "stdiom.h"
off64_t
ftell_common(FILE *iop)
{
ptrdiff_t adjust;
off64_t tres;
rmutex_t *lk;
FLOCKFILE(lk, iop);
/*
* If we're dealing with a memory stream, we need to flush the internal
* state before we try and determine the location. This is especially
* important for open_wmemstream() as it will have buffered bytes, but
* we need to convert that to wide characters before we proceed. If we
* have no file descriptor, then the units that the backing store are in
* can be arbitrary.
*/
if (_get_fd(iop) == -1) {
(void) _fflush_u(iop);
}
if (iop->_cnt < 0)
iop->_cnt = 0;
if (iop->_flag & _IOREAD) {
adjust = (ptrdiff_t)-iop->_cnt;
} else if (iop->_flag & (_IOWRT | _IORW)) {
adjust = 0;
if (((iop->_flag & (_IOWRT | _IONBF)) == _IOWRT) &&
(iop->_base != 0)) {
adjust = iop->_ptr - iop->_base;
} else if ((iop->_flag & _IORW) && (iop->_base != 0)) {
adjust = (ptrdiff_t)-iop->_cnt;
}
} else {
errno = EBADF; /* file descriptor refers to no open file */
FUNLOCKFILE(lk);
return (EOF);
}
tres = _xseek64(iop, 0, SEEK_CUR);
if (tres >= 0)
tres += adjust;
FUNLOCKFILE(lk);
return (tres);
}
long
ftell(FILE *iop)
{
off64_t tres;
tres = ftell_common(iop);
if (tres > LONG_MAX) {
errno = EOVERFLOW;
return (EOF);
}
return ((long)tres);
}
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