1/*	$OpenBSD: stdio.c,v 1.9 2005/08/08 08:05:36 espie Exp $ */
2/*-
3 * Copyright (c) 1990, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Chris Torek.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include <errno.h>
35#include <fcntl.h>
36#include <unistd.h>
37#include <stdio.h>
38#include "local.h"
39
40/*
41 * Small standard I/O/seek/close functions.
42 * These maintain the `known seek offset' for seek optimisation.
43 */
44int
45__sread(void *cookie, char *buf, int n)
46{
47	FILE *fp = cookie;
48	int ret;
49
50	ret = TEMP_FAILURE_RETRY(read(fp->_file, buf, n));
51	/* if the read succeeded, update the current offset */
52	if (ret >= 0)
53		fp->_offset += ret;
54	else
55		fp->_flags &= ~__SOFF;	/* paranoia */
56	return (ret);
57}
58
59int
60__swrite(void *cookie, const char *buf, int n)
61{
62	FILE *fp = cookie;
63
64	if (fp->_flags & __SAPP)
65		(void) TEMP_FAILURE_RETRY(lseek(fp->_file, (off_t)0, SEEK_END));
66	fp->_flags &= ~__SOFF;	/* in case FAPPEND mode is set */
67	return TEMP_FAILURE_RETRY(write(fp->_file, buf, n));
68}
69
70fpos_t
71__sseek(void *cookie, fpos_t offset, int whence)
72{
73	FILE *fp = cookie;
74	off_t ret;
75
76	ret = TEMP_FAILURE_RETRY(lseek(fp->_file, (off_t)offset, whence));
77	if (ret == (off_t)-1)
78		fp->_flags &= ~__SOFF;
79	else {
80		fp->_flags |= __SOFF;
81		fp->_offset = ret;
82	}
83	return (ret);
84}
85
86int
87__sclose(void *cookie)
88{
89	return close(((FILE *)cookie)->_file);
90}
91