]>
Commit | Line | Data |
---|---|---|
15c0b25d AP |
1 | // Copyright 2018 The Go Authors. All rights reserved. |
2 | // Use of this source code is governed by a BSD-style | |
3 | // license that can be found in the LICENSE file. | |
4 | ||
5 | // +build freebsd netbsd | |
6 | ||
7 | package unix | |
8 | ||
9 | import ( | |
10 | "strings" | |
11 | "unsafe" | |
12 | ) | |
13 | ||
14 | // Derive extattr namespace and attribute name | |
15 | ||
16 | func xattrnamespace(fullattr string) (ns int, attr string, err error) { | |
17 | s := strings.IndexByte(fullattr, '.') | |
18 | if s == -1 { | |
19 | return -1, "", ENOATTR | |
20 | } | |
21 | ||
22 | namespace := fullattr[0:s] | |
23 | attr = fullattr[s+1:] | |
24 | ||
25 | switch namespace { | |
26 | case "user": | |
27 | return EXTATTR_NAMESPACE_USER, attr, nil | |
28 | case "system": | |
29 | return EXTATTR_NAMESPACE_SYSTEM, attr, nil | |
30 | default: | |
31 | return -1, "", ENOATTR | |
32 | } | |
33 | } | |
34 | ||
35 | func initxattrdest(dest []byte, idx int) (d unsafe.Pointer) { | |
36 | if len(dest) > idx { | |
37 | return unsafe.Pointer(&dest[idx]) | |
38 | } else { | |
39 | return unsafe.Pointer(_zero) | |
40 | } | |
41 | } | |
42 | ||
43 | // FreeBSD and NetBSD implement their own syscalls to handle extended attributes | |
44 | ||
45 | func Getxattr(file string, attr string, dest []byte) (sz int, err error) { | |
46 | d := initxattrdest(dest, 0) | |
47 | destsize := len(dest) | |
48 | ||
49 | nsid, a, err := xattrnamespace(attr) | |
50 | if err != nil { | |
51 | return -1, err | |
52 | } | |
53 | ||
54 | return ExtattrGetFile(file, nsid, a, uintptr(d), destsize) | |
55 | } | |
56 | ||
57 | func Fgetxattr(fd int, attr string, dest []byte) (sz int, err error) { | |
58 | d := initxattrdest(dest, 0) | |
59 | destsize := len(dest) | |
60 | ||
61 | nsid, a, err := xattrnamespace(attr) | |
62 | if err != nil { | |
63 | return -1, err | |
64 | } | |
65 | ||
66 | return ExtattrGetFd(fd, nsid, a, uintptr(d), destsize) | |
67 | } | |
68 | ||
69 | func Lgetxattr(link string, attr string, dest []byte) (sz int, err error) { | |
70 | d := initxattrdest(dest, 0) | |
71 | destsize := len(dest) | |
72 | ||
73 | nsid, a, err := xattrnamespace(attr) | |
74 | if err != nil { | |
75 | return -1, err | |
76 | } | |
77 | ||
78 | return ExtattrGetLink(link, nsid, a, uintptr(d), destsize) | |
79 | } | |
80 | ||
81 | // flags are unused on FreeBSD | |
82 | ||
83 | func Fsetxattr(fd int, attr string, data []byte, flags int) (err error) { | |
107c1cdb ND |
84 | var d unsafe.Pointer |
85 | if len(data) > 0 { | |
86 | d = unsafe.Pointer(&data[0]) | |
87 | } | |
15c0b25d AP |
88 | datasiz := len(data) |
89 | ||
90 | nsid, a, err := xattrnamespace(attr) | |
91 | if err != nil { | |
92 | return | |
93 | } | |
94 | ||
95 | _, err = ExtattrSetFd(fd, nsid, a, uintptr(d), datasiz) | |
96 | return | |
97 | } | |
98 | ||
99 | func Setxattr(file string, attr string, data []byte, flags int) (err error) { | |
107c1cdb ND |
100 | var d unsafe.Pointer |
101 | if len(data) > 0 { | |
102 | d = unsafe.Pointer(&data[0]) | |
103 | } | |
15c0b25d AP |
104 | datasiz := len(data) |
105 | ||
106 | nsid, a, err := xattrnamespace(attr) | |
107 | if err != nil { | |
108 | return | |
109 | } | |
110 | ||
111 | _, err = ExtattrSetFile(file, nsid, a, uintptr(d), datasiz) | |
112 | return | |
113 | } | |
114 | ||
115 | func Lsetxattr(link string, attr string, data []byte, flags int) (err error) { | |
107c1cdb ND |
116 | var d unsafe.Pointer |
117 | if len(data) > 0 { | |
118 | d = unsafe.Pointer(&data[0]) | |
119 | } | |
15c0b25d AP |
120 | datasiz := len(data) |
121 | ||
122 | nsid, a, err := xattrnamespace(attr) | |
123 | if err != nil { | |
124 | return | |
125 | } | |
126 | ||
127 | _, err = ExtattrSetLink(link, nsid, a, uintptr(d), datasiz) | |
128 | return | |
129 | } | |
130 | ||
131 | func Removexattr(file string, attr string) (err error) { | |
132 | nsid, a, err := xattrnamespace(attr) | |
133 | if err != nil { | |
134 | return | |
135 | } | |
136 | ||
137 | err = ExtattrDeleteFile(file, nsid, a) | |
138 | return | |
139 | } | |
140 | ||
141 | func Fremovexattr(fd int, attr string) (err error) { | |
142 | nsid, a, err := xattrnamespace(attr) | |
143 | if err != nil { | |
144 | return | |
145 | } | |
146 | ||
147 | err = ExtattrDeleteFd(fd, nsid, a) | |
148 | return | |
149 | } | |
150 | ||
151 | func Lremovexattr(link string, attr string) (err error) { | |
152 | nsid, a, err := xattrnamespace(attr) | |
153 | if err != nil { | |
154 | return | |
155 | } | |
156 | ||
157 | err = ExtattrDeleteLink(link, nsid, a) | |
158 | return | |
159 | } | |
160 | ||
161 | func Listxattr(file string, dest []byte) (sz int, err error) { | |
162 | d := initxattrdest(dest, 0) | |
163 | destsiz := len(dest) | |
164 | ||
165 | // FreeBSD won't allow you to list xattrs from multiple namespaces | |
166 | s := 0 | |
167 | for _, nsid := range [...]int{EXTATTR_NAMESPACE_USER, EXTATTR_NAMESPACE_SYSTEM} { | |
168 | stmp, e := ExtattrListFile(file, nsid, uintptr(d), destsiz) | |
169 | ||
170 | /* Errors accessing system attrs are ignored so that | |
171 | * we can implement the Linux-like behavior of omitting errors that | |
172 | * we don't have read permissions on | |
173 | * | |
174 | * Linux will still error if we ask for user attributes on a file that | |
175 | * we don't have read permissions on, so don't ignore those errors | |
176 | */ | |
177 | if e != nil && e == EPERM && nsid != EXTATTR_NAMESPACE_USER { | |
178 | continue | |
179 | } else if e != nil { | |
180 | return s, e | |
181 | } | |
182 | ||
183 | s += stmp | |
184 | destsiz -= s | |
185 | if destsiz < 0 { | |
186 | destsiz = 0 | |
187 | } | |
188 | d = initxattrdest(dest, s) | |
189 | } | |
190 | ||
191 | return s, nil | |
192 | } | |
193 | ||
194 | func Flistxattr(fd int, dest []byte) (sz int, err error) { | |
195 | d := initxattrdest(dest, 0) | |
196 | destsiz := len(dest) | |
197 | ||
198 | s := 0 | |
199 | for _, nsid := range [...]int{EXTATTR_NAMESPACE_USER, EXTATTR_NAMESPACE_SYSTEM} { | |
200 | stmp, e := ExtattrListFd(fd, nsid, uintptr(d), destsiz) | |
201 | if e != nil && e == EPERM && nsid != EXTATTR_NAMESPACE_USER { | |
202 | continue | |
203 | } else if e != nil { | |
204 | return s, e | |
205 | } | |
206 | ||
207 | s += stmp | |
208 | destsiz -= s | |
209 | if destsiz < 0 { | |
210 | destsiz = 0 | |
211 | } | |
212 | d = initxattrdest(dest, s) | |
213 | } | |
214 | ||
215 | return s, nil | |
216 | } | |
217 | ||
218 | func Llistxattr(link string, dest []byte) (sz int, err error) { | |
219 | d := initxattrdest(dest, 0) | |
220 | destsiz := len(dest) | |
221 | ||
222 | s := 0 | |
223 | for _, nsid := range [...]int{EXTATTR_NAMESPACE_USER, EXTATTR_NAMESPACE_SYSTEM} { | |
224 | stmp, e := ExtattrListLink(link, nsid, uintptr(d), destsiz) | |
225 | if e != nil && e == EPERM && nsid != EXTATTR_NAMESPACE_USER { | |
226 | continue | |
227 | } else if e != nil { | |
228 | return s, e | |
229 | } | |
230 | ||
231 | s += stmp | |
232 | destsiz -= s | |
233 | if destsiz < 0 { | |
234 | destsiz = 0 | |
235 | } | |
236 | d = initxattrdest(dest, s) | |
237 | } | |
238 | ||
239 | return s, nil | |
240 | } |