4 Copyright (C) Simo Sorce 2005-2008
6 ** NOTE! The following LGPL license applies to the ldb
7 ** library. This does NOT imply that all of Samba is released
10 This library is free software; you can redistribute it and/or
11 modify it under the terms of the GNU Lesser General Public
12 License as published by the Free Software Foundation; either
13 version 3 of the License, or (at your option) any later version.
15 This library is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
20 You should have received a copy of the GNU Lesser General Public
21 License along with this library; if not, see <http://www.gnu.org/licenses/>.
27 * Component: ldb paged results control module
29 * Description: this module caches a complete search and sends back
30 * results in chunks as asked by the client
35 #include "ldb_module.h"
37 struct message_store {
38 /* keep the whole ldb_reply as an optimization
39 * instead of freeing and talloc-ing the container
42 struct message_store *next;
47 struct results_store {
49 struct private_data *priv;
54 struct results_store *next;
56 struct message_store *first;
57 struct message_store *last;
60 struct message_store *first_ref;
61 struct message_store *last_ref;
63 struct ldb_control **controls;
69 struct results_store *store;
73 static int store_destructor(struct results_store *del)
75 struct private_data *priv = del->priv;
76 struct results_store *loop;
78 if (priv->store == del) {
79 priv->store = del->next;
83 for (loop = priv->store; loop; loop = loop->next) {
84 if (loop->next == del) {
85 loop->next = del->next;
90 /* is not in list ? */
94 static struct results_store *new_store(struct private_data *priv)
96 struct results_store *newr;
97 int new_id = priv->next_free_id++;
99 /* TODO: we should have a limit on the number of
100 * outstanding paged searches
103 newr = talloc(priv, struct results_store);
104 if (!newr) return NULL;
108 newr->cookie = talloc_asprintf(newr, "%d", new_id);
114 newr->timestamp = time(NULL);
117 newr->num_entries = 0;
118 newr->first_ref = NULL;
119 newr->controls = NULL;
121 newr->next = priv->store;
124 talloc_set_destructor(newr, store_destructor);
129 struct paged_context {
130 struct ldb_module *module;
131 struct ldb_request *req;
133 struct results_store *store;
135 struct ldb_control **controls;
138 static int paged_results(struct paged_context *ac)
140 struct ldb_paged_control *paged;
141 struct message_store *msg;
142 int i, num_ctrls, ret;
144 if (ac->store == NULL) {
145 return LDB_ERR_OPERATIONS_ERROR;
148 while (ac->store->num_entries > 0 && ac->size > 0) {
149 msg = ac->store->first;
150 ret = ldb_module_send_entry(ac->req, msg->r->message, msg->r->controls);
151 if (ret != LDB_SUCCESS) {
155 ac->store->first = msg->next;
157 ac->store->num_entries--;
161 while (ac->store->first_ref != NULL) {
162 msg = ac->store->first_ref;
163 ret = ldb_module_send_referral(ac->req, msg->r->referral);
164 if (ret != LDB_SUCCESS) {
168 ac->store->first_ref = msg->next;
172 /* return result done */
176 if (ac->store->controls != NULL) {
177 while (ac->store->controls[i]) i++; /* counting */
182 ac->controls = talloc_array(ac, struct ldb_control *, num_ctrls +1);
183 if (ac->controls == NULL) {
184 return LDB_ERR_OPERATIONS_ERROR;
186 ac->controls[num_ctrls] = NULL;
188 for (i = 0; i < (num_ctrls -1); i++) {
189 ac->controls[i] = talloc_reference(ac->controls, ac->store->controls[i]);
192 ac->controls[i] = talloc(ac->controls, struct ldb_control);
193 if (ac->controls[i] == NULL) {
194 return LDB_ERR_OPERATIONS_ERROR;
197 ac->controls[i]->oid = talloc_strdup(ac->controls[i],
198 LDB_CONTROL_PAGED_RESULTS_OID);
199 if (ac->controls[i]->oid == NULL) {
200 return LDB_ERR_OPERATIONS_ERROR;
203 ac->controls[i]->critical = 0;
205 paged = talloc(ac->controls[i], struct ldb_paged_control);
207 return LDB_ERR_OPERATIONS_ERROR;
210 ac->controls[i]->data = paged;
214 paged->cookie = NULL;
215 paged->cookie_len = 0;
217 paged->size = ac->store->num_entries;
218 paged->cookie = talloc_strdup(paged, ac->store->cookie);
219 paged->cookie_len = strlen(paged->cookie) + 1;
225 static int paged_search_callback(struct ldb_request *req, struct ldb_reply *ares)
227 struct paged_context *ac ;
228 struct message_store *msg_store;
231 ac = talloc_get_type(req->context, struct paged_context);
234 return ldb_module_done(ac->req, NULL, NULL,
235 LDB_ERR_OPERATIONS_ERROR);
237 if (ares->error != LDB_SUCCESS) {
238 return ldb_module_done(ac->req, ares->controls,
239 ares->response, ares->error);
242 switch (ares->type) {
243 case LDB_REPLY_ENTRY:
244 msg_store = talloc(ac->store, struct message_store);
245 if (msg_store == NULL) {
246 return ldb_module_done(ac->req, NULL, NULL,
247 LDB_ERR_OPERATIONS_ERROR);
249 msg_store->next = NULL;
250 msg_store->r = talloc_steal(msg_store, ares);
252 if (ac->store->first == NULL) {
253 ac->store->first = msg_store;
255 ac->store->last->next = msg_store;
257 ac->store->last = msg_store;
259 ac->store->num_entries++;
263 case LDB_REPLY_REFERRAL:
264 msg_store = talloc(ac->store, struct message_store);
265 if (msg_store == NULL) {
266 return ldb_module_done(ac->req, NULL, NULL,
267 LDB_ERR_OPERATIONS_ERROR);
269 msg_store->next = NULL;
270 msg_store->r = talloc_steal(msg_store, ares);
272 if (ac->store->first_ref == NULL) {
273 ac->store->first_ref = msg_store;
275 ac->store->last_ref->next = msg_store;
277 ac->store->last_ref = msg_store;
282 ac->store->controls = talloc_move(ac->store, &ares->controls);
283 ret = paged_results(ac);
284 return ldb_module_done(ac->req, ac->controls,
285 ares->response, ret);
291 static int paged_search(struct ldb_module *module, struct ldb_request *req)
293 struct ldb_context *ldb;
294 struct ldb_control *control;
295 struct private_data *private_data;
296 struct ldb_paged_control *paged_ctrl;
297 struct ldb_control **saved_controls;
298 struct ldb_request *search_req;
299 struct paged_context *ac;
302 ldb = ldb_module_get_ctx(module);
304 /* check if there's a paged request control */
305 control = ldb_request_get_control(req, LDB_CONTROL_PAGED_RESULTS_OID);
306 if (control == NULL) {
307 /* not found go on */
308 return ldb_next_request(module, req);
311 paged_ctrl = talloc_get_type(control->data, struct ldb_paged_control);
313 return LDB_ERR_PROTOCOL_ERROR;
316 private_data = talloc_get_type(ldb_module_get_private(module),
317 struct private_data);
319 ac = talloc_zero(req, struct paged_context);
321 ldb_set_errstring(ldb, "Out of Memory");
322 return LDB_ERR_OPERATIONS_ERROR;
327 ac->size = paged_ctrl->size;
329 /* check if it is a continuation search the store */
330 if (paged_ctrl->cookie_len == 0) {
331 if (paged_ctrl->size == 0) {
332 return LDB_ERR_OPERATIONS_ERROR;
335 ac->store = new_store(private_data);
336 if (ac->store == NULL) {
337 return LDB_ERR_OPERATIONS_ERROR;
340 ret = ldb_build_search_req_ex(&search_req, ldb, ac,
342 req->op.search.scope,
344 req->op.search.attrs,
347 paged_search_callback,
350 /* save it locally and remove it from the list */
351 /* we do not need to replace them later as we
352 * are keeping the original req intact */
353 if (!save_controls(control, search_req, &saved_controls)) {
354 return LDB_ERR_OPERATIONS_ERROR;
357 return ldb_next_request(module, search_req);
360 struct results_store *current = NULL;
362 /* TODO: age out old outstanding requests */
363 for (current = private_data->store; current; current = current->next) {
364 if (strcmp(current->cookie, paged_ctrl->cookie) == 0) {
365 current->timestamp = time(NULL);
369 if (current == NULL) {
370 return LDB_ERR_UNWILLING_TO_PERFORM;
375 /* check if it is an abandon */
377 return ldb_module_done(req, NULL, NULL,
381 ret = paged_results(ac);
382 if (ret != LDB_SUCCESS) {
383 return ldb_module_done(req, NULL, NULL, ret);
385 return ldb_module_done(req, ac->controls, NULL,
390 static int paged_request_init(struct ldb_module *module)
392 struct ldb_context *ldb;
393 struct private_data *data;
396 ldb = ldb_module_get_ctx(module);
398 data = talloc(module, struct private_data);
400 return LDB_ERR_OTHER;
403 data->next_free_id = 1;
405 ldb_module_set_private(module, data);
407 ret = ldb_mod_register_control(module, LDB_CONTROL_PAGED_RESULTS_OID);
408 if (ret != LDB_SUCCESS) {
409 ldb_debug(ldb, LDB_DEBUG_WARNING,
411 "Unable to register control with rootdse!\n");
414 return ldb_next_init(module);
417 const struct ldb_module_ops ldb_paged_results_module_ops = {
418 .name = "paged_results",
419 .search = paged_search,
420 .init_context = paged_request_init