1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1988 AT&T */
/* All Rights Reserved */
/*
* University Copyright- Copyright (c) 1982, 1986, 1988
* The Regents of the University of California
* All Rights Reserved
*
* University Acknowledgment- Portions of this document are derived from
* software developed by the University of California, Berkeley, and its
* contributors.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include "synonyms.h"
#include "file64.h"
#include <sys/types.h>
#include <stdio.h>
#include <mtlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <limits.h>
#include <thread.h>
#include <synch.h>
#include <stdlib.h>
#include <errno.h>
#include "stdiom.h"
#include "xpg6.h"
/* Final argument to _endopen depends on build environment */
#define LARGE_OPEN (_FILE_OFFSET_BITS == 64)
FILE *
fopen(const char *name, const char *type) /* open name, return new stream */
{
FILE *iop;
FILE *rc;
iop = _findiop();
/*
* Note that iop is not locked here, since no other thread could
* possibly call _endopen with the same iop at this point.
*/
rc = _endopen(name, type, iop, LARGE_OPEN);
if (rc == NULL && iop != NULL)
iop->_flag = 0; /* release iop */
return (rc);
}
static FILE *
_freopen_null(const char *type, FILE *iop)
{
char plus, mode;
int oflag, nflag, fd, accmode;
mbstate_t *mb;
if (iop == NULL || iop->_flag == 0) {
errno = EBADF;
return (NULL);
}
if (!(iop->_flag & _IONBF) && (iop->_flag & (_IOWRT | _IOREAD | _IORW)))
(void) _fflush_u(iop);
if (iop->_flag & _IOMYBUF) {
free((char *)iop->_base - PUSHBACK);
}
iop->_base = NULL;
iop->_ptr = NULL;
/*
* Clear stream orientation, clear stream encoding rule, and set
* stream's mbstate_t object to describe an initial conversion state.
*/
mb = _getmbstate(iop);
if (mb != NULL)
(void) memset(mb, 0, sizeof (mbstate_t));
iop->_cnt = 0;
_setorientation(iop, _NO_MODE);
fd = FILENO(iop);
mode = type[0];
if (mode != 'r' && mode != 'w' && mode != 'a') {
errno = EINVAL;
goto errret;
}
if ((oflag = fcntl(fd, F_GETFL)) == -1)
goto errret;
if ((plus = type[1]) == 'b')
plus = type[2];
/*
* Because the filename has not been specified, the underlying file
* will not be closed and reopened. The access modes of an open
* file descriptor can't be changed via fcntl(). When '+' is
* specified, the old access mode needs to be O_RDWR. When 'r' is
* specified, the old access mode needs to be O_RDONLY or O_RDWR.
* When 'a' or 'w' is specified, the old access mode needs to be
* O_WRONLY or O_RDWR. Otherwise, fail with EBADF, indicating that
* the underlying file descriptor was not opened with a mode that
* would allow the stream to do successful I/O with the requested mode.
*/
accmode = oflag & O_ACCMODE;
if ((accmode == O_RDONLY && (mode != 'r' || plus == '+')) ||
(accmode == O_WRONLY && (mode == 'r' || plus == '+'))) {
(void) close(fd);
errno = EBADF;
goto errret_noclose;
}
#ifdef _LP64
iop->_flag &= ~0377; /* clear lower 8-bits */
if (mode == 'r') {
iop->_flag |= _IOREAD;
nflag = oflag & ~O_APPEND;
} else if (mode == 'w') {
iop->_flag |= _IOWRT;
nflag = oflag & ~O_APPEND;
} else {
iop->_flag |= _IOWRT;
nflag = oflag | O_APPEND;
}
if (plus == '+') {
iop->_flag = (iop->_flag & ~(_IOREAD | _IOWRT)) | _IORW;
}
#else
if (mode == 'r') {
iop->_flag = _IOREAD;
nflag = oflag & ~O_APPEND;
} else if (mode == 'w') {
iop->_flag = _IOWRT;
nflag = oflag & ~O_APPEND;
} else {
iop->_flag = _IOWRT;
nflag = oflag | O_APPEND;
}
if (plus == '+') {
iop->_flag = _IORW;
}
#endif
/*
* Change mode of underlying fd as much as possible without closing
* and reopening it. Ignore truncate failures, eg. with stdout.
*/
if (mode == 'w')
(void) ftruncate64(fd, (off64_t)0);
if (fcntl(fd, F_SETFL, nflag) == -1)
goto errret;
/* ignore seek failures, eg. with pipes */
(void) lseek64(fd, (off64_t)0, SEEK_SET);
return (iop);
errret:
if (errno != EBADF)
(void) close(fd);
errret_noclose:
iop->_flag = 0; /* release iop */
return (NULL);
}
FILE *
freopen(const char *name, const char *type, FILE *iop)
{
FILE *rc;
rmutex_t *lk;
if (name == NULL && __xpg6 & _C99SUSv3_freopen_NULL_filename) {
/*
* XPG6: If name is a null pointer, freopen will attempt to
* change the mode of the stream to that specified by type.
*/
FLOCKFILE(lk, iop);
rc = _freopen_null(type, iop);
FUNLOCKFILE(lk);
return (rc);
}
/*
* there may be concurrent calls to reopen the same stream - need
* to make freopen() atomic
*/
FLOCKFILE(lk, iop);
/*
* new function to do everything that fclose() does, except
* to release the iop - this cannot yet be released since
* _endopen() is yet to be called on this iop
*/
(void) close_fd(iop);
rc = _endopen(name, type, iop, LARGE_OPEN);
if (rc == NULL)
iop->_flag = 0; /* release iop */
FUNLOCKFILE(lk);
return (rc);
}
|
