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
|
/*
* Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Hyra nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/vfs.h>
#include <sys/mount.h>
#include <sys/errno.h>
#include <vm/dynalloc.h>
#include <string.h>
/*
* Fetches the filename within a path at
* the nth index denoted by `idx'
*
* Returns memory allocated by dynalloc()
* containing the filename.
*
* XXX: MUST FREE RETURN VALUE WITH dynfree() WHEN
* DONE!
*/
char *
vfs_get_fname_at(const char *path, size_t idx)
{
size_t pathlen = strlen(path);
size_t fname_len;
char *path_tmp = dynalloc(pathlen + 2);
char *ret = NULL;
char *start_ptr, *ptr;
/* Make one-based */
++idx;
if (path_tmp == NULL) {
return NULL;
}
ptr = path_tmp;
memcpy(path_tmp, path, pathlen + 1);
/*
* We want to by default have a '/' at the end
* to keep the parsing logic from getting more
* complicated than it needs to be.
*/
path_tmp[pathlen] = '/';
path_tmp[pathlen + 1] = '\0';
/* Skip any leading slashes */
while (*ptr == '/')
++ptr;
start_ptr = ptr;
/* Get each filename */
while (*ptr != '\0') {
/* Handle duplicate delimiter */
if (*ptr == '/' && *(ptr + 1) == '/') {
/*
* Snip this delimiter and skip, the next
* will be read and filename returned (if of course
* the index is reached).
*/
*(ptr++) = '\0';
continue;
}
if (*ptr == '/') {
*(ptr++) = '\0';
/* Continue if index not reached */
if ((--idx) != 0) {
start_ptr = ptr;
continue;
}
/* Index has been reached, start_ptr contains name */
fname_len = strlen(start_ptr);
ret = dynalloc(fname_len + 1);
if (ret != NULL) {
memcpy(ret, start_ptr, fname_len + 1);
}
break;
}
++ptr;
}
dynfree(path_tmp);
return ret;
}
/*
* Fetches a vnode from a path.
*
* @path: Path to fetch vnode from.
* @vp: Output var for fetched vnode.
*
* Returns 0 on success.
*/
int
vfs_path_to_node(const char *path, struct vnode **vp)
{
struct vnode *vnode = g_root_vnode;
struct mount *mp;
struct fs_info *fs;
char *name;
int s = 0, fs_caps = 0;
if (strcmp(path, "/") == 0 || !vfs_is_valid_path(path)) {
return -EINVAL;
} else if (*path != '/') {
return -EINVAL;
}
/* See if we have a mountpoint with this name */
name = vfs_get_fname_at(path, 0);
if (vfs_get_mp(name, &mp) == 0) {
fs = mp->fs;
vnode = fs->vnode;
}
/* Fetch filesystem capabilities if we can */
if (vnode->fs != NULL) {
fs = vnode->fs;
fs_caps = fs->caps;
}
/*
* If the filesystem requires full-path lookups, we can try
* throwing the full path at the filesystem to see if
* it'll give us a vnode.
*/
if (__TEST(fs_caps, FSCAP_FULLPATH)) {
s = vfs_vget(vnode, path, &vnode);
goto done;
}
for (size_t i = 1;; ++i) {
name = vfs_get_fname_at(path, i);
if (name == NULL) break;
s = vfs_vget(vnode, name, &vnode);
dynfree(name);
if (s != 0) break;
}
done:
if (vp != NULL && s == 0) {
*vp = vnode;
}
return s;
}
|
