1 /****************************************************************************
2 * fs/vfs/fs_fsync.c
3 *
4 * Copyright (C) 2007-2009, 2013-2014, 2016-2017 Gregory Nutt. All rights
5 * reserved.
6 * Author: Gregory Nutt <gnutt@nuttx.org>
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 *
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
16 * the documentation and/or other materials provided with the
17 * distribution.
18 * 3. Neither the name NuttX nor the names of its contributors may be
19 * used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
29 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
32 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33 * POSSIBILITY OF SUCH DAMAGE.
34 *
35 ****************************************************************************/
36
37 /****************************************************************************
38 * Included Files
39 ****************************************************************************/
40
41 #include "vfs_config.h"
42
43 #include "unistd.h"
44 #include "fcntl.h"
45 #include "errno.h"
46 #include "assert.h"
47
48
49
50 #include "vnode.h"
51
52 /****************************************************************************
53 * Public Functions
54 ****************************************************************************/
55
56 /****************************************************************************
57 * Name: file_fsync
58 *
59 * Description:
60 * Equivalent to the standard fsync() function except that is accepts a
61 * struct file instance instead of a file descriptor and it does not set
62 * the errno variable.
63 *
64 ****************************************************************************/
65
file_fsync(struct file * filep)66 int file_fsync(struct file *filep)
67 {
68 int ret;
69
70 /* Was this file opened for write access? */
71
72 if ((filep->f_oflags & O_ACCMODE) == 0)
73 {
74 ret = EBADF;
75 goto errout;
76 }
77
78 /* Is this vnode a registered mountpoint? Does it support the
79 * sync operations may be relevant to device drivers but only
80 * the mountpoint operations vtable contains a sync method.
81 */
82
83 if (!filep || !filep->ops || !filep->ops->fsync)
84 {
85 ret = EINVAL;
86 goto errout;
87 }
88
89 /* Yes, then tell the mountpoint to sync this file */
90
91 ret = filep->ops->fsync(filep);
92 if (ret >= 0)
93 {
94 return OK;
95 }
96
97 ret = -ret;
98
99 errout:
100 set_errno(ret);
101 return VFS_ERROR;
102 }
103
104 /****************************************************************************
105 * Name: fsync
106 *
107 * Description:
108 * This func simply binds vnode sync methods to the sync system call.
109 *
110 ****************************************************************************/
111
fsync(int fd)112 int fsync(int fd)
113 {
114 struct file *filep = NULL;
115
116 /* Get the file structure corresponding to the file descriptor. */
117
118 int ret = fs_getfilep(fd, &filep);
119 if (ret < 0)
120 {
121 /* The errno value has already been set */
122 return VFS_ERROR;
123 }
124
125 /* Perform the fsync operation */
126
127 return file_fsync(filep);
128 }
129
130