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 * 3. 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 * @(#)stdio.c 8.1 (Berkeley) 6/4/93
33 * $FreeBSD: src/lib/libc/stdio/stdio.c,v 1.28 2008/05/05 16:14:02 jhb Exp $
34 */
35
36 #include "namespace.h"
37 #include <errno.h>
38 #include <fcntl.h>
39 #include <limits.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <unistd.h>
43 #include "un-namespace.h"
44 #include "local.h"
45
46 /*
47 * Small standard I/O/seek/close functions.
48 */
49 int
__sread(void * cookie,char * buf,int n)50 __sread(void *cookie, char *buf, int n)
51 {
52 FILE *fp = cookie;
53
54 return(_read(fp->pub._fileno, buf, (size_t)n));
55 }
56
57 int
__swrite(void * cookie,const char * buf,int n)58 __swrite(void *cookie, const char *buf, int n)
59 {
60 FILE *fp = cookie;
61
62 return (_write(fp->pub._fileno, buf, (size_t)n));
63 }
64
65 fpos_t
__sseek(void * cookie,fpos_t offset,int whence)66 __sseek(void *cookie, fpos_t offset, int whence)
67 {
68 FILE *fp = cookie;
69
70 return (lseek(fp->pub._fileno, (off_t)offset, whence));
71 }
72
73 int
__sclose(void * cookie)74 __sclose(void *cookie)
75 {
76
77 return (_close(((FILE *)cookie)->pub._fileno));
78 }
79
80 /*
81 * Higher level wrappers.
82 */
83 int
_sread(FILE * fp,char * buf,int n)84 _sread(FILE *fp, char *buf, int n)
85 {
86 int ret;
87
88 ret = (*fp->_read)(fp->_cookie, buf, n);
89 if (ret > 0) {
90 if (fp->pub._flags & __SOFF) {
91 if (fp->_offset <= OFF_MAX - ret)
92 fp->_offset += ret;
93 else
94 fp->pub._flags &= ~__SOFF;
95 }
96 } else if (ret < 0)
97 fp->pub._flags &= ~__SOFF;
98 return (ret);
99 }
100
101 int
_swrite(FILE * fp,const char * buf,int n)102 _swrite(FILE *fp, const char *buf, int n)
103 {
104 int ret;
105 int serrno;
106
107 if (fp->pub._flags & __SAPP) {
108 serrno = errno;
109 if (_sseek(fp, (fpos_t)0, SEEK_END) == -1 &&
110 (fp->pub._flags & __SOPT))
111 return (-1);
112 errno = serrno;
113 }
114 ret = (*fp->_write)(fp->_cookie, buf, n);
115 /* __SOFF removed even on success in case O_APPEND mode is set. */
116 if (ret >= 0) {
117 if ((fp->pub._flags & (__SAPP|__SOFF)) == (__SAPP|__SOFF) &&
118 fp->_offset <= OFF_MAX - ret)
119 fp->_offset += ret;
120 else
121 fp->pub._flags &= ~__SOFF;
122
123 } else if (ret < 0)
124 fp->pub._flags &= ~__SOFF;
125 return (ret);
126 }
127
128 fpos_t
_sseek(FILE * fp,fpos_t offset,int whence)129 _sseek(FILE *fp, fpos_t offset, int whence)
130 {
131 fpos_t ret;
132 int serrno, errret;
133
134 serrno = errno;
135 errno = 0;
136 ret = (*fp->_seek)(fp->_cookie, offset, whence);
137 errret = errno;
138 if (errno == 0)
139 errno = serrno;
140 /*
141 * Disallow negative seeks per POSIX.
142 * It is needed here to help upper level caller
143 * in the cases it can't detect.
144 */
145 if (ret < 0) {
146 if (errret == 0) {
147 if (offset != 0 || whence != SEEK_CUR) {
148 if (HASUB(fp))
149 FREEUB(fp);
150 fp->pub._p = fp->_bf._base;
151 fp->pub._r = 0;
152 fp->pub._flags &= ~__SEOF;
153 }
154 fp->pub._flags |= __SERR;
155 errno = EINVAL;
156 } else if (errret == ESPIPE)
157 fp->pub._flags &= ~__SAPP;
158 fp->pub._flags &= ~__SOFF;
159 ret = -1;
160 } else if (fp->pub._flags & __SOPT) {
161 fp->pub._flags |= __SOFF;
162 fp->_offset = ret;
163 }
164 return (ret);
165 }
166