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
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
|
/*
* Copyright (C) 2004-2007 Internet Systems Consortium, Inc. ("ISC")
* Copyright (C) 1999-2001 Internet Software Consortium.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: dbiterator.h,v 1.25 2007-06-19 23:47:16 tbox Exp $ */
#ifndef DNS_DBITERATOR_H
#define DNS_DBITERATOR_H 1
/*****
***** Module Info
*****/
/*! \file dns/dbiterator.h
* \brief
* The DNS DB Iterator interface allows iteration of all of the nodes in a
* database.
*
* The dns_dbiterator_t type is like a "virtual class". To actually use
* it, an implementation of the class is required. This implementation is
* supplied by the database.
*
* It is the client's responsibility to call dns_db_detachnode() on all
* nodes returned.
*
* XXX <more> XXX
*
* MP:
*\li The iterator itself is not locked. The caller must ensure
* synchronization.
*
*\li The iterator methods ensure appropriate database locking.
*
* Reliability:
*\li No anticipated impact.
*
* Resources:
*\li TBS
*
* Security:
*\li No anticipated impact.
*
* Standards:
*\li None.
*/
/*****
***** Imports
*****/
#include <isc/lang.h>
#include <isc/magic.h>
#include <dns/types.h>
ISC_LANG_BEGINDECLS
/*****
***** Types
*****/
typedef struct dns_dbiteratormethods {
void (*destroy)(dns_dbiterator_t **iteratorp);
isc_result_t (*first)(dns_dbiterator_t *iterator);
isc_result_t (*last)(dns_dbiterator_t *iterator);
isc_result_t (*seek)(dns_dbiterator_t *iterator, dns_name_t *name);
isc_result_t (*prev)(dns_dbiterator_t *iterator);
isc_result_t (*next)(dns_dbiterator_t *iterator);
isc_result_t (*current)(dns_dbiterator_t *iterator,
dns_dbnode_t **nodep, dns_name_t *name);
isc_result_t (*pause)(dns_dbiterator_t *iterator);
isc_result_t (*origin)(dns_dbiterator_t *iterator,
dns_name_t *name);
} dns_dbiteratormethods_t;
#define DNS_DBITERATOR_MAGIC ISC_MAGIC('D','N','S','I')
#define DNS_DBITERATOR_VALID(dbi) ISC_MAGIC_VALID(dbi, DNS_DBITERATOR_MAGIC)
/*%
* This structure is actually just the common prefix of a DNS db
* implementation's version of a dns_dbiterator_t.
*
* Clients may use the 'db' field of this structure. Except for that field,
* direct use of this structure by clients is forbidden. DB implementations
* may change the structure. 'magic' must be DNS_DBITERATOR_MAGIC for any of
* the dns_dbiterator routines to work. DB iterator implementations must
* maintain all DB iterator invariants.
*/
struct dns_dbiterator {
/* Unlocked. */
unsigned int magic;
dns_dbiteratormethods_t * methods;
dns_db_t * db;
isc_boolean_t relative_names;
isc_boolean_t cleaning;
};
void
dns_dbiterator_destroy(dns_dbiterator_t **iteratorp);
/*%<
* Destroy '*iteratorp'.
*
* Requires:
*
*\li '*iteratorp' is a valid iterator.
*
* Ensures:
*
*\li All resources used by the iterator are freed.
*
*\li *iteratorp == NULL.
*/
isc_result_t
dns_dbiterator_first(dns_dbiterator_t *iterator);
/*%<
* Move the node cursor to the first node in the database (if any).
*
* Requires:
*\li 'iterator' is a valid iterator.
*
* Returns:
*\li #ISC_R_SUCCESS
*\li #ISC_R_NOMORE There are no nodes in the database.
*
*\li Other results are possible, depending on the DB implementation.
*/
isc_result_t
dns_dbiterator_last(dns_dbiterator_t *iterator);
/*%<
* Move the node cursor to the last node in the database (if any).
*
* Requires:
*\li 'iterator' is a valid iterator.
*
* Returns:
*\li #ISC_R_SUCCESS
*\li #ISC_R_NOMORE There are no nodes in the database.
*
*\li Other results are possible, depending on the DB implementation.
*/
isc_result_t
dns_dbiterator_seek(dns_dbiterator_t *iterator, dns_name_t *name);
/*%<
* Move the node cursor to the node with name 'name'.
*
* Requires:
*\li 'iterator' is a valid iterator.
*
*\li 'name' is a valid name.
*
* Returns:
*\li #ISC_R_SUCCESS
*\li #ISC_R_NOTFOUND
*
*\li Other results are possible, depending on the DB implementation.
*/
isc_result_t
dns_dbiterator_prev(dns_dbiterator_t *iterator);
/*%<
* Move the node cursor to the previous node in the database (if any).
*
* Requires:
*\li 'iterator' is a valid iterator.
*
* Returns:
*\li #ISC_R_SUCCESS
*\li #ISC_R_NOMORE There are no more nodes in the
* database.
*
*\li Other results are possible, depending on the DB implementation.
*/
isc_result_t
dns_dbiterator_next(dns_dbiterator_t *iterator);
/*%<
* Move the node cursor to the next node in the database (if any).
*
* Requires:
*\li 'iterator' is a valid iterator.
*
* Returns:
*\li #ISC_R_SUCCESS
*\li #ISC_R_NOMORE There are no more nodes in the
* database.
*
*\li Other results are possible, depending on the DB implementation.
*/
isc_result_t
dns_dbiterator_current(dns_dbiterator_t *iterator, dns_dbnode_t **nodep,
dns_name_t *name);
/*%<
* Return the current node.
*
* Notes:
*\li If 'name' is not NULL, it will be set to the name of the node.
*
* Requires:
*\li 'iterator' is a valid iterator.
*
*\li nodep != NULL && *nodep == NULL
*
*\li The node cursor of 'iterator' is at a valid location (i.e. the
* result of last call to a cursor movement command was ISC_R_SUCCESS).
*
*\li 'name' is NULL, or is a valid name with a dedicated buffer.
*
* Returns:
*
*\li #ISC_R_SUCCESS
*\li #DNS_R_NEWORIGIN If this iterator was created with
* 'relative_names' set to ISC_TRUE,
* then #DNS_R_NEWORIGIN will be returned
* when the origin the names are
* relative to changes. This result
* can occur only when 'name' is not
* NULL. This is also a successful
* result.
*
*\li Other results are possible, depending on the DB implementation.
*/
isc_result_t
dns_dbiterator_pause(dns_dbiterator_t *iterator);
/*%<
* Pause iteration.
*
* Calling a cursor movement method or dns_dbiterator_current() may cause
* database locks to be acquired. Rather than reacquire these locks every
* time one of these routines is called, the locks may simply be held.
* Calling dns_dbiterator_pause() releases any such locks. Iterator clients
* should call this routine any time they are not going to execute another
* iterator method in the immediate future.
*
* Requires:
*\li 'iterator' is a valid iterator.
*
* Ensures:
*\li Any database locks being held for efficiency of iterator access are
* released.
*
* Returns:
*\li #ISC_R_SUCCESS
*
*\li Other results are possible, depending on the DB implementation.
*/
isc_result_t
dns_dbiterator_origin(dns_dbiterator_t *iterator, dns_name_t *name);
/*%<
* Return the origin to which returned node names are relative.
*
* Requires:
*
*\li 'iterator' is a valid relative_names iterator.
*
*\li 'name' is a valid name with a dedicated buffer.
*
* Returns:
*
*\li #ISC_R_SUCCESS
*\li #ISC_R_NOSPACE
*
*\li Other results are possible, depending on the DB implementation.
*/
void
dns_dbiterator_setcleanmode(dns_dbiterator_t *iterator, isc_boolean_t mode);
/*%<
* Indicate that the given iterator is/is not cleaning the DB.
*
* Notes:
*\li When 'mode' is ISC_TRUE,
*
* Requires:
*\li 'iterator' is a valid iterator.
*/
ISC_LANG_ENDDECLS
#endif /* DNS_DBITERATOR_H */
|
