1 /****************************************************************************
2 * fs/vfs/fs_statfs.c
3 *
4 * Licensed to the Apache Software Foundation (ASF) under one or more
5 * contributor license agreements. See the NOTICE file distributed with
6 * this work for additional information regarding copyright ownership. The
7 * ASF licenses this file to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance with the
9 * License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
16 * License for the specific language governing permissions and limitations
17 * under the License.
18 *
19 ****************************************************************************/
20
21 /****************************************************************************
22 * Included Files
23 ****************************************************************************/
24
25 #include "vfs_config.h"
26
27 #include "sys/statfs.h"
28 #include "string.h"
29 #include "sched.h"
30 #include "vnode.h"
31 #include "fs/mount.h"
32 #include "errno.h"
33 #include "stdlib.h"
34
35 /****************************************************************************
36 * Public Functions
37 ****************************************************************************/
38
39 /****************************************************************************
40 * Name: statfs
41 *
42 * Returned Value:
43 * Zero on success; -1 on failure with errno set:
44 *
45 * EACCES Search permission is denied for one of the directories in the
46 * path prefix of path.
47 * EFAULT Bad address.
48 * ENOENT A component of the path path does not exist, or the path is an
49 * empty string.
50 * ENOMEM Out of memory
51 * ENOTDIR A component of the path is not a directory.
52 * ENOSYS The file system does not support this call.
53 *
54 ****************************************************************************/
55
statfs(const char * path,struct statfs * buf)56 int statfs(const char *path, struct statfs *buf)
57 {
58 struct Vnode *vnode = NULL;
59 struct Mount *mnt = NULL;
60 int ret = OK;
61
62 /* Sanity checks */
63 if (!path || !buf)
64 {
65 ret = -EFAULT;
66 goto errout;
67 }
68 if (!path[0])
69 {
70 ret = -ENOENT;
71 goto errout;
72 }
73 /* Get an vnode for this file */
74 VnodeHold();
75 ret = VnodeLookup(path, &vnode, 0);
76 if (ret < 0)
77 {
78 VnodeDrop();
79 goto errout;
80 }
81 vnode->useCount++;
82 VnodeDrop();
83
84 mnt = vnode->originMount;
85 if (mnt == NULL || mnt->ops == NULL || mnt->ops->Statfs == NULL)
86 {
87 ret = -ENOSYS;
88 goto errout_with_useCount;
89 }
90 else
91 {
92 ret = mnt->ops->Statfs(mnt, buf);
93 if (ret < 0)
94 {
95 goto errout_with_useCount;
96 }
97 }
98
99 VnodeHold();
100 vnode->useCount--;
101 VnodeDrop();
102
103 return OK;
104
105 /* Failure conditions always set the errno appropriately */
106
107 errout_with_useCount:
108 VnodeHold();
109 vnode->useCount--;
110 VnodeDrop();
111 errout:
112 set_errno(-ret);
113 return VFS_ERROR;
114 }
115