xref: /netbsd-src/lib/libc/stdio/fseek.c (revision b7ae68fde0d8ef1c03714e8bbb1ee7c6118ea93b)
1 /*	$NetBSD: fseek.c,v 1.22 2006/01/26 10:48:18 kleink Exp $	*/
2 
3 /*-
4  * Copyright (c) 2005 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by David Laight.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of The NetBSD Foundation nor the names of its
19  *    contributors may be used to endorse or promote products derived
20  *    from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
26  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32  * POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 #if defined(LIBC_SCCS) && !defined(lint)
37 __RCSID("$NetBSD: fseek.c,v 1.22 2006/01/26 10:48:18 kleink Exp $");
38 #endif /* LIBC_SCCS and not lint */
39 
40 #include <sys/types.h>
41 #include <sys/stat.h>
42 
43 #include "namespace.h"
44 #include <assert.h>
45 #include <errno.h>
46 #include <fcntl.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include "reentrant.h"
50 #include "local.h"
51 
52 /*
53  * Seek the given file to the given offset.
54  * Zero extend the offset if SEEK_SET to allow access to 4GB files
55  */
56 int
57 fseek(FILE *fp, long l_offset, int whence)
58 {
59 	off_t offset;
60 
61 	if (whence == SEEK_SET)
62 		offset = (unsigned long)l_offset;
63 	else
64 		offset = l_offset;
65 	return fseeko(fp, offset, whence);
66 }
67