fopen.c revision 165903 
1/*-
2 * Copyright (c) 1990, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Chris Torek.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#if defined(LIBC_SCCS) && !defined(lint)
34static char sccsid[] = "@(#)fopen.c	8.1 (Berkeley) 6/4/93";
35#endif /* LIBC_SCCS and not lint */
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD: head/lib/libc/stdio/fopen.c 165903 2007-01-09 00:28:16Z imp $");
38
39#include "namespace.h"
40#include <sys/types.h>
41#include <sys/stat.h>
42#include <fcntl.h>
43#include <stdio.h>
44#include <errno.h>
45#include "un-namespace.h"
46
47#include "local.h"
48
49FILE *
50fopen(file, mode)
51	const char * __restrict file;
52	const char * __restrict mode;
53{
54	FILE *fp;
55	int f;
56	int flags, oflags;
57
58	if ((flags = __sflags(mode, &oflags)) == 0)
59		return (NULL);
60	if ((fp = __sfp()) == NULL)
61		return (NULL);
62	if ((f = _open(file, oflags, DEFFILEMODE)) < 0) {
63		fp->_flags = 0;			/* release */
64		return (NULL);
65	}
66	fp->_file = f;
67	fp->_flags = flags;
68	fp->_cookie = fp;
69	fp->_read = __sread;
70	fp->_write = __swrite;
71	fp->_seek = __sseek;
72	fp->_close = __sclose;
73	/*
74	 * When opening in append mode, even though we use O_APPEND,
75	 * we need to seek to the end so that ftell() gets the right
76	 * answer.  If the user then alters the seek pointer, or
77	 * the file extends, this will fail, but there is not much
78	 * we can do about this.  (We could set __SAPP and check in
79	 * fseek and ftell.)
80	 */
81	if (oflags & O_APPEND)
82		(void)_sseek(fp, (fpos_t)0, SEEK_END);
83	return (fp);
84}
85