1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1990, 1993 The Regents of the University of California.
5 * Copyright (c) 2013 Mariusz Zaborski <[email protected]>
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Chris Torek.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #if defined(LIBC_SCCS) && !defined(lint)
37 static char sccsid[] = "@(#)fclose.c 8.1 (Berkeley) 6/4/93";
38 #endif /* LIBC_SCCS and not lint */
39 #include "namespace.h"
40 #include <errno.h>
41 #include <stdbool.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include "un-namespace.h"
45 #include <spinlock.h>
46 #include "libc_private.h"
47 #include "local.h"
48
49 static int
cleanfile(FILE * fp,bool c)50 cleanfile(FILE *fp, bool c)
51 {
52 int r;
53
54 r = fp->_flags & __SWR ? __sflush(fp) : 0;
55 if (c) {
56 if (fp->_close != NULL && (*fp->_close)(fp->_cookie) < 0)
57 r = EOF;
58 }
59
60 if (fp->_flags & __SMBF)
61 free((char *)fp->_bf._base);
62 if (HASUB(fp))
63 FREEUB(fp);
64 if (HASLB(fp))
65 FREELB(fp);
66 fp->_file = -1;
67 fp->_r = fp->_w = 0; /* Mess up if reaccessed. */
68
69 /*
70 * Lock the spinlock used to protect __sglue list walk in
71 * __sfp(). The __sfp() uses fp->_flags == 0 test as an
72 * indication of the unused FILE.
73 *
74 * Taking the lock prevents possible compiler or processor
75 * reordering of the writes performed before the final _flags
76 * cleanup, making sure that we are done with the FILE before
77 * it is considered available.
78 */
79 STDIO_THREAD_LOCK();
80 fp->_flags = 0; /* Release this FILE for reuse. */
81 STDIO_THREAD_UNLOCK();
82
83 return (r);
84 }
85
86 int
fdclose(FILE * fp,int * fdp)87 fdclose(FILE *fp, int *fdp)
88 {
89 int r, err;
90
91 if (fdp != NULL)
92 *fdp = -1;
93
94 if (fp->_flags == 0) { /* not open! */
95 errno = EBADF;
96 return (EOF);
97 }
98
99 FLOCKFILE_CANCELSAFE(fp);
100 r = 0;
101 if (fp->_close != __sclose) {
102 r = EOF;
103 errno = EOPNOTSUPP;
104 } else if (fp->_file < 0) {
105 r = EOF;
106 errno = EBADF;
107 }
108 if (r == EOF) {
109 err = errno;
110 (void)cleanfile(fp, true);
111 errno = err;
112 } else {
113 if (fdp != NULL)
114 *fdp = fp->_file;
115 r = cleanfile(fp, false);
116 }
117 FUNLOCKFILE_CANCELSAFE();
118
119 return (r);
120 }
121
122 int
fclose(FILE * fp)123 fclose(FILE *fp)
124 {
125 int r;
126
127 if (fp->_flags == 0) { /* not open! */
128 errno = EBADF;
129 return (EOF);
130 }
131
132 FLOCKFILE_CANCELSAFE(fp);
133 r = cleanfile(fp, true);
134 FUNLOCKFILE_CANCELSAFE();
135
136 return (r);
137 }
138