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[] = "@(#)stdio.c	8.1 (Berkeley) 6/4/93";
35#endif /* LIBC_SCCS and not lint */
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD: src/lib/libc/stdio/stdio.c,v 1.28 2008/05/05 16:14:02 jhb Exp $");
38
39#include "namespace.h"
40#include <errno.h>
41#include <fcntl.h>
42#include <limits.h>
43#include <stdio.h>
44#include <stdlib.h>
45#include <unistd.h>
46#include "un-namespace.h"
47#include "local.h"
48
49/*
50 * Small standard I/O/seek/close functions.
51 */
52int
53__sread(cookie, buf, n)
54	void *cookie;
55	char *buf;
56	int n;
57{
58	FILE *fp = cookie;
59
60	return(_read(fp->_file, buf, (size_t)n));
61}
62
63int
64__swrite(cookie, buf, n)
65	void *cookie;
66	char const *buf;
67	int n;
68{
69	FILE *fp = cookie;
70
71	return (_write(fp->_file, buf, (size_t)n));
72}
73
74fpos_t
75__sseek(cookie, offset, whence)
76	void *cookie;
77	fpos_t offset;
78	int whence;
79{
80	FILE *fp = cookie;
81
82	return (lseek(fp->_file, (off_t)offset, whence));
83}
84
85int
86__sclose(cookie)
87	void *cookie;
88{
89
90	return (_close(((FILE *)cookie)->_file));
91}
92
93/*
94 * Higher level wrappers.
95 */
96int
97_sread(fp, buf, n)
98	FILE *fp;
99	char *buf;
100	int n;
101{
102	int ret;
103
104	ret = (*fp->_read)(fp->_cookie, buf, n);
105	if (ret > 0) {
106		if (fp->_flags & __SOFF) {
107			if (fp->_offset <= OFF_MAX - ret)
108				fp->_offset += ret;
109			else
110				fp->_flags &= ~__SOFF;
111		}
112	} else if (ret < 0)
113		fp->_flags &= ~__SOFF;
114	return (ret);
115}
116
117int
118_swrite(fp, buf, n)
119	FILE *fp;
120	char const *buf;
121	int n;
122{
123	int ret;
124	int serrno;
125
126	if (fp->_flags & __SAPP) {
127		serrno = errno;
128		if (_sseek(fp, (fpos_t)0, SEEK_END) == -1 &&
129		    (fp->_flags & __SOPT))
130			return (-1);
131		errno = serrno;
132	}
133	ret = (*fp->_write)(fp->_cookie, buf, n);
134	/* __SOFF removed even on success in case O_APPEND mode is set. */
135	if (ret >= 0) {
136		if ((fp->_flags & (__SAPP|__SOFF)) == (__SAPP|__SOFF) &&
137		    fp->_offset <= OFF_MAX - ret)
138			fp->_offset += ret;
139		else
140			fp->_flags &= ~__SOFF;
141
142	} else if (ret < 0)
143		fp->_flags &= ~__SOFF;
144	return (ret);
145}
146
147fpos_t
148_sseek(fp, offset, whence)
149	FILE *fp;
150	fpos_t offset;
151	int whence;
152{
153	fpos_t ret;
154	int serrno, errret;
155
156	serrno = errno;
157	errno = 0;
158	ret = (*fp->_seek)(fp->_cookie, offset, whence);
159	errret = errno;
160	if (errno == 0)
161		errno = serrno;
162	/*
163	 * Disallow negative seeks per POSIX.
164	 * It is needed here to help upper level caller
165	 * in the cases it can't detect.
166	 */
167	if (ret < 0) {
168		if (errret == 0) {
169			if (offset != 0 || whence != SEEK_CUR) {
170				if (HASUB(fp))
171					FREEUB(fp);
172				fp->_p = fp->_bf._base;
173				fp->_r = 0;
174				fp->_flags &= ~__SEOF;
175			}
176			fp->_flags |= __SERR;
177			errno = EINVAL;
178		} else if (errret == ESPIPE)
179			fp->_flags &= ~__SAPP;
180		fp->_flags &= ~__SOFF;
181		ret = -1;
182	} else if (fp->_flags & __SOPT) {
183		fp->_flags |= __SOFF;
184		fp->_offset = ret;
185	}
186	return (ret);
187}
188