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[] = "@(#)freopen.c 8.1 (Berkeley) 6/4/93";
35#endif /* LIBC_SCCS and not lint */
36#include <sys/cdefs.h>
| 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[] = "@(#)freopen.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/freopen.c 165903 2007-01-09 00:28:16Z imp $");
| 37__FBSDID("$FreeBSD: head/lib/libc/stdio/freopen.c 176628 2008-02-27 19:02:02Z jhb $");
|
38
39#include "namespace.h"
40#include <sys/types.h>
41#include <sys/stat.h>
42#include <fcntl.h>
43#include <errno.h>
44#include <unistd.h>
45#include <stdio.h>
46#include <stdlib.h>
47#include "un-namespace.h"
48#include "libc_private.h"
49#include "local.h"
50
51/*
52 * Re-direct an existing, open (probably) file to some other file.
53 * ANSI is written such that the original file gets closed if at
54 * all possible, no matter what.
55 */
56FILE *
57freopen(file, mode, fp)
58 const char * __restrict file;
59 const char * __restrict mode;
60 FILE *fp;
61{
62 int f;
63 int dflags, flags, isopen, oflags, sverrno, wantfd;
64
65 if ((flags = __sflags(mode, &oflags)) == 0) {
66 sverrno = errno;
67 (void) fclose(fp);
68 errno = sverrno;
69 return (NULL);
70 }
71
72 FLOCKFILE(fp);
73
74 if (!__sdidinit)
75 __sinit();
76
77 /*
78 * If the filename is a NULL pointer, the caller is asking us to
79 * re-open the same file with a different mode. We allow this only
80 * if the modes are compatible.
81 */
82 if (file == NULL) {
83 /* See comment below regarding freopen() of closed files. */
84 if (fp->_flags == 0) {
85 FUNLOCKFILE(fp);
86 errno = EINVAL;
87 return (NULL);
88 }
89 if ((dflags = _fcntl(fp->_file, F_GETFL)) < 0) {
90 sverrno = errno;
91 fclose(fp);
92 FUNLOCKFILE(fp);
93 errno = sverrno;
94 return (NULL);
95 }
96 if ((dflags & O_ACCMODE) != O_RDWR && (dflags & O_ACCMODE) !=
97 (oflags & O_ACCMODE)) {
98 fclose(fp);
99 FUNLOCKFILE(fp);
100 errno = EINVAL;
101 return (NULL);
102 }
103 if (fp->_flags & __SWR)
104 (void) __sflush(fp);
105 if ((oflags ^ dflags) & O_APPEND) {
106 dflags &= ~O_APPEND;
107 dflags |= oflags & O_APPEND;
108 if (_fcntl(fp->_file, F_SETFL, dflags) < 0) {
109 sverrno = errno;
110 fclose(fp);
111 FUNLOCKFILE(fp);
112 errno = sverrno;
113 return (NULL);
114 }
115 }
116 if (oflags & O_TRUNC)
117 (void) ftruncate(fp->_file, (off_t)0);
118 if (!(oflags & O_APPEND))
119 (void) _sseek(fp, (fpos_t)0, SEEK_SET);
120 f = fp->_file;
121 isopen = 0;
122 wantfd = -1;
123 goto finish;
124 }
125
126 /*
127 * There are actually programs that depend on being able to "freopen"
128 * descriptors that weren't originally open. Keep this from breaking.
129 * Remember whether the stream was open to begin with, and which file
130 * descriptor (if any) was associated with it. If it was attached to
131 * a descriptor, defer closing it; freopen("/dev/stdin", "r", stdin)
132 * should work. This is unnecessary if it was not a Unix file.
133 */
134 if (fp->_flags == 0) {
135 fp->_flags = __SEOF; /* hold on to it */
136 isopen = 0;
137 wantfd = -1;
138 } else {
139 /* flush the stream; ANSI doesn't require this. */
140 if (fp->_flags & __SWR)
141 (void) __sflush(fp);
142 /* if close is NULL, closing is a no-op, hence pointless */
143 isopen = fp->_close != NULL;
144 if ((wantfd = fp->_file) < 0 && isopen) {
145 (void) (*fp->_close)(fp->_cookie);
146 isopen = 0;
147 }
148 }
149
150 /* Get a new descriptor to refer to the new file. */
151 f = _open(file, oflags, DEFFILEMODE);
152 if (f < 0 && isopen) {
153 /* If out of fd's close the old one and try again. */
154 if (errno == ENFILE || errno == EMFILE) {
155 (void) (*fp->_close)(fp->_cookie);
156 isopen = 0;
157 f = _open(file, oflags, DEFFILEMODE);
158 }
159 }
160 sverrno = errno;
161
162finish:
163 /*
164 * Finish closing fp. Even if the open succeeded above, we cannot
165 * keep fp->_base: it may be the wrong size. This loses the effect
166 * of any setbuffer calls, but stdio has always done this before.
167 */
168 if (isopen)
169 (void) (*fp->_close)(fp->_cookie);
170 if (fp->_flags & __SMBF)
171 free((char *)fp->_bf._base);
172 fp->_w = 0;
173 fp->_r = 0;
174 fp->_p = NULL;
175 fp->_bf._base = NULL;
176 fp->_bf._size = 0;
177 fp->_lbfsize = 0;
178 if (HASUB(fp))
179 FREEUB(fp);
180 fp->_ub._size = 0;
181 if (HASLB(fp))
182 FREELB(fp);
183 fp->_lb._size = 0;
184 fp->_extra->orientation = 0;
185 memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
186
187 if (f < 0) { /* did not get it after all */
188 fp->_flags = 0; /* set it free */
189 FUNLOCKFILE(fp);
190 errno = sverrno; /* restore in case _close clobbered */
191 return (NULL);
192 }
193
194 /*
195 * If reopening something that was open before on a real file, try
196 * to maintain the descriptor. Various C library routines (perror)
197 * assume stderr is always fd STDERR_FILENO, even if being freopen'd.
198 */
199 if (wantfd >= 0 && f != wantfd) {
200 if (_dup2(f, wantfd) >= 0) {
201 (void)_close(f);
202 f = wantfd;
203 }
204 }
205
| 38
39#include "namespace.h"
40#include <sys/types.h>
41#include <sys/stat.h>
42#include <fcntl.h>
43#include <errno.h>
44#include <unistd.h>
45#include <stdio.h>
46#include <stdlib.h>
47#include "un-namespace.h"
48#include "libc_private.h"
49#include "local.h"
50
51/*
52 * Re-direct an existing, open (probably) file to some other file.
53 * ANSI is written such that the original file gets closed if at
54 * all possible, no matter what.
55 */
56FILE *
57freopen(file, mode, fp)
58 const char * __restrict file;
59 const char * __restrict mode;
60 FILE *fp;
61{
62 int f;
63 int dflags, flags, isopen, oflags, sverrno, wantfd;
64
65 if ((flags = __sflags(mode, &oflags)) == 0) {
66 sverrno = errno;
67 (void) fclose(fp);
68 errno = sverrno;
69 return (NULL);
70 }
71
72 FLOCKFILE(fp);
73
74 if (!__sdidinit)
75 __sinit();
76
77 /*
78 * If the filename is a NULL pointer, the caller is asking us to
79 * re-open the same file with a different mode. We allow this only
80 * if the modes are compatible.
81 */
82 if (file == NULL) {
83 /* See comment below regarding freopen() of closed files. */
84 if (fp->_flags == 0) {
85 FUNLOCKFILE(fp);
86 errno = EINVAL;
87 return (NULL);
88 }
89 if ((dflags = _fcntl(fp->_file, F_GETFL)) < 0) {
90 sverrno = errno;
91 fclose(fp);
92 FUNLOCKFILE(fp);
93 errno = sverrno;
94 return (NULL);
95 }
96 if ((dflags & O_ACCMODE) != O_RDWR && (dflags & O_ACCMODE) !=
97 (oflags & O_ACCMODE)) {
98 fclose(fp);
99 FUNLOCKFILE(fp);
100 errno = EINVAL;
101 return (NULL);
102 }
103 if (fp->_flags & __SWR)
104 (void) __sflush(fp);
105 if ((oflags ^ dflags) & O_APPEND) {
106 dflags &= ~O_APPEND;
107 dflags |= oflags & O_APPEND;
108 if (_fcntl(fp->_file, F_SETFL, dflags) < 0) {
109 sverrno = errno;
110 fclose(fp);
111 FUNLOCKFILE(fp);
112 errno = sverrno;
113 return (NULL);
114 }
115 }
116 if (oflags & O_TRUNC)
117 (void) ftruncate(fp->_file, (off_t)0);
118 if (!(oflags & O_APPEND))
119 (void) _sseek(fp, (fpos_t)0, SEEK_SET);
120 f = fp->_file;
121 isopen = 0;
122 wantfd = -1;
123 goto finish;
124 }
125
126 /*
127 * There are actually programs that depend on being able to "freopen"
128 * descriptors that weren't originally open. Keep this from breaking.
129 * Remember whether the stream was open to begin with, and which file
130 * descriptor (if any) was associated with it. If it was attached to
131 * a descriptor, defer closing it; freopen("/dev/stdin", "r", stdin)
132 * should work. This is unnecessary if it was not a Unix file.
133 */
134 if (fp->_flags == 0) {
135 fp->_flags = __SEOF; /* hold on to it */
136 isopen = 0;
137 wantfd = -1;
138 } else {
139 /* flush the stream; ANSI doesn't require this. */
140 if (fp->_flags & __SWR)
141 (void) __sflush(fp);
142 /* if close is NULL, closing is a no-op, hence pointless */
143 isopen = fp->_close != NULL;
144 if ((wantfd = fp->_file) < 0 && isopen) {
145 (void) (*fp->_close)(fp->_cookie);
146 isopen = 0;
147 }
148 }
149
150 /* Get a new descriptor to refer to the new file. */
151 f = _open(file, oflags, DEFFILEMODE);
152 if (f < 0 && isopen) {
153 /* If out of fd's close the old one and try again. */
154 if (errno == ENFILE || errno == EMFILE) {
155 (void) (*fp->_close)(fp->_cookie);
156 isopen = 0;
157 f = _open(file, oflags, DEFFILEMODE);
158 }
159 }
160 sverrno = errno;
161
162finish:
163 /*
164 * Finish closing fp. Even if the open succeeded above, we cannot
165 * keep fp->_base: it may be the wrong size. This loses the effect
166 * of any setbuffer calls, but stdio has always done this before.
167 */
168 if (isopen)
169 (void) (*fp->_close)(fp->_cookie);
170 if (fp->_flags & __SMBF)
171 free((char *)fp->_bf._base);
172 fp->_w = 0;
173 fp->_r = 0;
174 fp->_p = NULL;
175 fp->_bf._base = NULL;
176 fp->_bf._size = 0;
177 fp->_lbfsize = 0;
178 if (HASUB(fp))
179 FREEUB(fp);
180 fp->_ub._size = 0;
181 if (HASLB(fp))
182 FREELB(fp);
183 fp->_lb._size = 0;
184 fp->_extra->orientation = 0;
185 memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
186
187 if (f < 0) { /* did not get it after all */
188 fp->_flags = 0; /* set it free */
189 FUNLOCKFILE(fp);
190 errno = sverrno; /* restore in case _close clobbered */
191 return (NULL);
192 }
193
194 /*
195 * If reopening something that was open before on a real file, try
196 * to maintain the descriptor. Various C library routines (perror)
197 * assume stderr is always fd STDERR_FILENO, even if being freopen'd.
198 */
199 if (wantfd >= 0 && f != wantfd) {
200 if (_dup2(f, wantfd) >= 0) {
201 (void)_close(f);
202 f = wantfd;
203 }
204 }
205
|
| 206 /*
207 * File descriptors are a full int, but _file is only a short.
208 * If we get a valid file descriptor that is greater than
209 * SHRT_MAX, then the fd will get sign-extended into an
210 * invalid file descriptor. Handle this case by failing the
211 * open.
212 */
213 if (f > SHRT_MAX) {
214 fp->_flags = 0; /* set it free */
215 FUNLOCKFILE(fp);
216 errno = EMFILE;
217 return (NULL);
218 }
219
|
206 fp->_flags = flags;
207 fp->_file = f;
208 fp->_cookie = fp;
209 fp->_read = __sread;
210 fp->_write = __swrite;
211 fp->_seek = __sseek;
212 fp->_close = __sclose;
213 /*
214 * When opening in append mode, even though we use O_APPEND,
215 * we need to seek to the end so that ftell() gets the right
216 * answer. If the user then alters the seek pointer, or
217 * the file extends, this will fail, but there is not much
218 * we can do about this. (We could set __SAPP and check in
219 * fseek and ftell.)
220 */
221 if (oflags & O_APPEND)
222 (void) _sseek(fp, (fpos_t)0, SEEK_END);
223 FUNLOCKFILE(fp);
224 return (fp);
225}
| 220 fp->_flags = flags;
221 fp->_file = f;
222 fp->_cookie = fp;
223 fp->_read = __sread;
224 fp->_write = __swrite;
225 fp->_seek = __sseek;
226 fp->_close = __sclose;
227 /*
228 * When opening in append mode, even though we use O_APPEND,
229 * we need to seek to the end so that ftell() gets the right
230 * answer. If the user then alters the seek pointer, or
231 * the file extends, this will fail, but there is not much
232 * we can do about this. (We could set __SAPP and check in
233 * fseek and ftell.)
234 */
235 if (oflags & O_APPEND)
236 (void) _sseek(fp, (fpos_t)0, SEEK_END);
237 FUNLOCKFILE(fp);
238 return (fp);
239}
|