1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*	Copyright (c) 1988 AT&T	*/
28/*	  All Rights Reserved	*/
29
30/*
31 * Seek for standard library.  Coordinates with buffering.
32 */
33
34#pragma weak _fseek = fseek
35
36#include "lint.h"
37#include "file64.h"
38#include "mtlib.h"
39#include <stdio.h>
40#include <errno.h>
41#include <thread.h>
42#include <synch.h>
43#include <unistd.h>
44#include <sys/types.h>
45#include "stdiom.h"
46
47int
48fseek(FILE *iop, long offset, int ptrname)
49{
50	off_t	p;
51	rmutex_t *lk;
52
53	FLOCKFILE(lk, iop);
54	iop->_flag &= ~_IOEOF;
55
56	if (!(iop->_flag & _IOREAD) && !(iop->_flag & (_IOWRT | _IORW))) {
57		errno = EBADF;
58		FUNLOCKFILE(lk);
59		return (-1);
60	}
61
62	if (iop->_flag & _IOREAD) {
63		if (ptrname == 1 && iop->_base && !(iop->_flag&_IONBF)) {
64			offset -= iop->_cnt;
65		}
66	} else if (iop->_flag & (_IOWRT | _IORW)) {
67		if (_fflush_u(iop) == EOF) {
68			FUNLOCKFILE(lk);
69			return (-1);
70		}
71	}
72	iop->_cnt = 0;
73	iop->_ptr = iop->_base;
74	if (iop->_flag & _IORW) {
75		iop->_flag &= ~(_IOREAD | _IOWRT);
76	}
77	p = _xseek(iop, (off_t)offset, ptrname);
78	FUNLOCKFILE(lk);
79	return ((p == (off_t)-1) ? -1: 0);
80}
81