1 /*
2 * Copyright (c) 2001-2002,2004 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software: you can redistribute it and/or modify it
6 * under the terms of the GNU Lesser General Public License as published by
7 * the Free Software Foundation, either version 2.1 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18 #ifndef __ATTRIBUTES_H__
19 #define __ATTRIBUTES_H__
20
21 #ifdef __cplusplus
22 extern "C" {
23 #endif
24
25 #include <stdint.h>
26
27 #ifndef ENOATTR
28 # define ENOATTR ENODATA
29 #endif
30
31 /*
32 * An almost-IRIX-compatible extended attributes API
33 * (the IRIX attribute "list" operation is missing, added ATTR_SECURE).
34 */
35
36 /*
37 * The maximum size (into the kernel or returned from the kernel) of an
38 * attribute value or the buffer used for an attr_list() call. Larger
39 * sizes will result in an E2BIG return code.
40 */
41 #define ATTR_MAX_VALUELEN (64*1024) /* max length of a value */
42
43
44 /*
45 * Flags that can be used with any of the simple attribute calls.
46 * All desired flags should be bit-wise OR'ed together.
47 */
48 #define ATTR_DONTFOLLOW 0x0001 /* do not follow symlinks for a pathname */
49 #define ATTR_ROOT 0x0002 /* use root namespace attributes in op */
50 #define ATTR_TRUST 0x0004 /* tell server we can be trusted to properly
51 handle extended attributes */
52 #define ATTR_SECURE 0x0008 /* use security namespace attributes in op */
53
54 /*
55 * Additional flags that can be used with the set() attribute call.
56 * All desired flags (from both lists) should be bit-wise OR'ed together.
57 */
58 #define ATTR_CREATE 0x0010 /* pure create: fail if attr already exists */
59 #define ATTR_REPLACE 0x0020 /* pure set: fail if attr does not exist */
60
61 /*
62 * Define how lists of attribute names are returned to the user from
63 * the attr_list() call. A large, 32bit aligned, buffer is passed in
64 * along with its size. We put an array of offsets at the top that each
65 * reference an attrlist_ent_t and pack the attrlist_ent_t's at the bottom.
66 */
67 typedef struct attrlist {
68 int32_t al_count; /* number of entries in attrlist */
69 int32_t al_more; /* T/F: more attrs (do call again) */
70 int32_t al_offset[1]; /* byte offsets of attrs [var-sized] */
71 } attrlist_t;
72
73 /*
74 * Show the interesting info about one attribute. This is what the
75 * al_offset[i] entry points to.
76 */
77 typedef struct attrlist_ent { /* data from attr_list() */
78 uint32_t a_valuelen; /* number bytes in value of attr */
79 char a_name[1]; /* attr name (NULL terminated) */
80 } attrlist_ent_t;
81
82 /*
83 * Given a pointer to the (char*) buffer containing the attr_list() result,
84 * and an index, return a pointer to the indicated attribute in the buffer.
85 */
86 #define ATTR_ENTRY(buffer, index) \
87 ((attrlist_ent_t *) \
88 &((char *)buffer)[ ((attrlist_t *)(buffer))->al_offset[index] ])
89
90 /*
91 * Implement a "cursor" for use in successive attr_list() calls.
92 * It provides a way to find the last attribute that was returned in the
93 * last attr_list() call so that we can get the next one without missing
94 * any. This should be zeroed before use and whenever it is desired to
95 * start over from the beginning of the attribute list. The only valid
96 * operation on a cursor is to zero it.
97 */
98 typedef struct attrlist_cursor {
99 uint32_t opaque[4]; /* an opaque cookie */
100 } attrlist_cursor_t;
101
102 /*
103 * Multi-attribute operation vector.
104 */
105 typedef struct attr_multiop {
106 int32_t am_opcode; /* operation to perform (ATTR_OP_GET, etc.) */
107 int32_t am_error; /* [out arg] result of this sub-op (an errno) */
108 char *am_attrname; /* attribute name to work with */
109 char *am_attrvalue; /* [in/out arg] attribute value (raw bytes) */
110 int32_t am_length; /* [in/out arg] length of value */
111 int32_t am_flags; /* flags (bit-wise OR of #defines above) */
112 } attr_multiop_t;
113 #define ATTR_MAX_MULTIOPS 128 /* max number ops in an oplist array */
114
115 /*
116 * Valid values of am_opcode.
117 */
118 #define ATTR_OP_GET 1 /* return the indicated attr's value */
119 #define ATTR_OP_SET 2 /* set/create the indicated attr/value pair */
120 #define ATTR_OP_REMOVE 3 /* remove the indicated attr */
121
122 /*
123 * Get the value of an attribute.
124 * Valuelength must be set to the maximum size of the value buffer, it will
125 * be set to the actual number of bytes used in the value buffer upon return.
126 * The return value is -1 on error (w/errno set appropriately), 0 on success.
127 */
128 EXPORT int attr_get (const char *__path, const char *__attrname,
129 char *__attrvalue, int *__valuelength, int __flags)
130 __attribute__ ((deprecated ("Use getxattr or lgetxattr instead")));
131 EXPORT int attr_getf (int __fd, const char *__attrname, char *__attrvalue,
132 int *__valuelength, int __flags)
133 __attribute__ ((deprecated ("Use fgetxattr instead")));
134
135 /*
136 * Set the value of an attribute, creating the attribute if necessary.
137 * The return value is -1 on error (w/errno set appropriately), 0 on success.
138 */
139 EXPORT int attr_set (const char *__path, const char *__attrname,
140 const char *__attrvalue, const int __valuelength,
141 int __flags)
142 __attribute__ ((deprecated ("Use setxattr or lsetxattr instead")));
143 EXPORT int attr_setf (int __fd, const char *__attrname,
144 const char *__attrvalue, const int __valuelength,
145 int __flags)
146 __attribute__ ((deprecated ("Use fsetxattr instead")));
147
148 /*
149 * Remove an attribute.
150 * The return value is -1 on error (w/errno set appropriately), 0 on success.
151 */
152 EXPORT int attr_remove (const char *__path, const char *__attrname,
153 int __flags)
154 __attribute__ ((deprecated ("Use removexattr or lremovexattr instead")));
155 EXPORT int attr_removef (int __fd, const char *__attrname, int __flags)
156 __attribute__ ((deprecated ("Use fremovexattr instead")));
157
158 /*
159 * List the names and sizes of the values of all the attributes of an object.
160 * "Cursor" must be allocated and zeroed before the first call, it is used
161 * to maintain context between system calls if all the attribute names won't
162 * fit into the buffer on the first system call.
163 * The return value is -1 on error (w/errno set appropriately), 0 on success.
164 */
165 EXPORT int attr_list(const char *__path, char *__buffer, const int __buffersize,
166 int __flags, attrlist_cursor_t *__cursor)
167 __attribute__ ((deprecated ("Use listxattr or llistxattr instead")));
168 EXPORT int attr_listf(int __fd, char *__buffer, const int __buffersize,
169 int __flags, attrlist_cursor_t *__cursor)
170 __attribute__ ((deprecated ("Use flistxattr instead")));
171
172 /*
173 * Operate on multiple attributes of the same object simultaneously.
174 *
175 * This call will save on system call overhead when many attributes are
176 * going to be operated on.
177 *
178 * The return value is -1 on error (w/errno set appropriately), 0 on success.
179 * Note that this call will not return -1 as a result of failure of any
180 * of the sub-operations, their return value is stored in each element
181 * of the operation array. This call will return -1 for a failure of the
182 * call as a whole, eg: if the pathname doesn't exist, or the fd is bad.
183 *
184 * The semantics and allowable values for the fields in a attr_multiop_t
185 * are the same as the semantics and allowable values for the arguments to
186 * the corresponding "simple" attribute interface. For example: the args
187 * to a ATTR_OP_GET are the same as the args to an attr_get() call.
188 */
189 EXPORT int attr_multi (const char *__path, attr_multiop_t *__oplist,
190 int __count, int __flags)
191 __attribute__ ((deprecated ("Use getxattr, setxattr, listxattr, removexattr instead")));
192 EXPORT int attr_multif (int __fd, attr_multiop_t *__oplist,
193 int __count, int __flags)
194 __attribute__ ((deprecated ("Use getxattr, setxattr, listxattr, removexattr instead")));
195
196 #ifdef __cplusplus
197 }
198 #endif
199
200 #endif /* __ATTRIBUTES_H__ */