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_includes.h"
36 #include "ldb_module.h"
38 struct message_store {
39 /* keep the whole ldb_reply as an optimization
40 * instead of freeing and talloc-ing the container
43 struct message_store *next;
48 struct results_store {
50 struct private_data *priv;
55 struct results_store *next;
57 struct message_store *first;
58 struct message_store *last;
61 struct message_store *first_ref;
62 struct message_store *last_ref;
64 struct ldb_control **controls;
70 struct results_store *store;
74 static int store_destructor(struct results_store *del)
76 struct private_data *priv = del->priv;
77 struct results_store *loop;
79 if (priv->store == del) {
80 priv->store = del->next;
84 for (loop = priv->store; loop; loop = loop->next) {
85 if (loop->next == del) {
86 loop->next = del->next;
91 /* is not in list ? */
95 static struct results_store *new_store(struct private_data *priv)
97 struct results_store *newr;
98 int new_id = priv->next_free_id++;
100 /* TODO: we should have a limit on the number of
101 * outstanding paged searches
104 newr = talloc(priv, struct results_store);
105 if (!newr) return NULL;
109 newr->cookie = talloc_asprintf(newr, "%d", new_id);
115 newr->timestamp = time(NULL);
118 newr->num_entries = 0;
119 newr->first_ref = NULL;
120 newr->controls = NULL;
122 newr->next = priv->store;
125 talloc_set_destructor(newr, store_destructor);
130 struct paged_context {
131 struct ldb_module *module;
132 struct ldb_request *req;
134 struct results_store *store;
136 struct ldb_control **controls;
139 static int paged_results(struct paged_context *ac)
141 struct ldb_paged_control *paged;
142 struct message_store *msg;
143 int i, num_ctrls, ret;
145 if (ac->store == NULL) {
146 return LDB_ERR_OPERATIONS_ERROR;
149 while (ac->store->num_entries > 0 && ac->size > 0) {
150 msg = ac->store->first;
151 ret = ldb_module_send_entry(ac->req, msg->r->message, msg->r->controls);
152 if (ret != LDB_SUCCESS) {
156 ac->store->first = msg->next;
158 ac->store->num_entries--;
162 while (ac->store->first_ref != NULL) {
163 msg = ac->store->first_ref;
164 ret = ldb_module_send_referral(ac->req, msg->r->referral);
165 if (ret != LDB_SUCCESS) {
169 ac->store->first_ref = msg->next;
173 /* return result done */
177 if (ac->store->controls != NULL) {
178 while (ac->store->controls[i]) i++; /* counting */
183 ac->controls = talloc_array(ac, struct ldb_control *, num_ctrls +1);
184 if (ac->controls == NULL) {
185 return LDB_ERR_OPERATIONS_ERROR;
187 ac->controls[num_ctrls] = NULL;
189 for (i = 0; i < (num_ctrls -1); i++) {
190 ac->controls[i] = talloc_reference(ac->controls, ac->store->controls[i]);
193 ac->controls[i] = talloc(ac->controls, struct ldb_control);
194 if (ac->controls[i] == NULL) {
195 return LDB_ERR_OPERATIONS_ERROR;
198 ac->controls[i]->oid = talloc_strdup(ac->controls[i],
199 LDB_CONTROL_PAGED_RESULTS_OID);
200 if (ac->controls[i]->oid == NULL) {
201 return LDB_ERR_OPERATIONS_ERROR;
204 ac->controls[i]->critical = 0;
206 paged = talloc(ac->controls[i], struct ldb_paged_control);
208 return LDB_ERR_OPERATIONS_ERROR;
211 ac->controls[i]->data = paged;
215 paged->cookie = NULL;
216 paged->cookie_len = 0;
218 paged->size = ac->store->num_entries;
219 paged->cookie = talloc_strdup(paged, ac->store->cookie);
220 paged->cookie_len = strlen(paged->cookie) + 1;
226 static int paged_search_callback(struct ldb_request *req, struct ldb_reply *ares)
228 struct paged_context *ac ;
229 struct message_store *msg_store;
232 ac = talloc_get_type(req->context, struct paged_context);
235 return ldb_module_done(ac->req, NULL, NULL,
236 LDB_ERR_OPERATIONS_ERROR);
238 if (ares->error != LDB_SUCCESS) {
239 return ldb_module_done(ac->req, ares->controls,
240 ares->response, ares->error);
243 switch (ares->type) {
244 case LDB_REPLY_ENTRY:
245 msg_store = talloc(ac->store, struct message_store);
246 if (msg_store == NULL) {
247 return ldb_module_done(ac->req, NULL, NULL,
248 LDB_ERR_OPERATIONS_ERROR);
250 msg_store->next = NULL;
251 msg_store->r = talloc_steal(msg_store, ares);
253 if (ac->store->first == NULL) {
254 ac->store->first = msg_store;
256 ac->store->last->next = msg_store;
258 ac->store->last = msg_store;
260 ac->store->num_entries++;
264 case LDB_REPLY_REFERRAL:
265 msg_store = talloc(ac->store, struct message_store);
266 if (msg_store == NULL) {
267 return ldb_module_done(ac->req, NULL, NULL,
268 LDB_ERR_OPERATIONS_ERROR);
270 msg_store->next = NULL;
271 msg_store->r = talloc_steal(msg_store, ares);
273 if (ac->store->first_ref == NULL) {
274 ac->store->first_ref = msg_store;
276 ac->store->last_ref->next = msg_store;
278 ac->store->last_ref = msg_store;
283 ac->store->controls = talloc_move(ac->store, &ares->controls);
284 ret = paged_results(ac);
285 return ldb_module_done(ac->req, ac->controls,
286 ares->response, ret);
292 static int paged_search(struct ldb_module *module, struct ldb_request *req)
294 struct ldb_context *ldb;
295 struct ldb_control *control;
296 struct private_data *private_data;
297 struct ldb_paged_control *paged_ctrl;
298 struct ldb_control **saved_controls;
299 struct ldb_request *search_req;
300 struct paged_context *ac;
303 ldb = ldb_module_get_ctx(module);
305 /* check if there's a paged request control */
306 control = ldb_request_get_control(req, LDB_CONTROL_PAGED_RESULTS_OID);
307 if (control == NULL) {
308 /* not found go on */
309 return ldb_next_request(module, req);
312 paged_ctrl = talloc_get_type(control->data, struct ldb_paged_control);
314 return LDB_ERR_PROTOCOL_ERROR;
317 private_data = talloc_get_type(ldb_module_get_private(module),
318 struct private_data);
320 ac = talloc_zero(req, struct paged_context);
322 ldb_set_errstring(ldb, "Out of Memory");
323 return LDB_ERR_OPERATIONS_ERROR;
328 ac->size = paged_ctrl->size;
330 /* check if it is a continuation search the store */
331 if (paged_ctrl->cookie_len == 0) {
332 if (paged_ctrl->size == 0) {
333 return LDB_ERR_OPERATIONS_ERROR;
336 ac->store = new_store(private_data);
337 if (ac->store == NULL) {
338 return LDB_ERR_OPERATIONS_ERROR;
341 ret = ldb_build_search_req_ex(&search_req, ldb, ac,
343 req->op.search.scope,
345 req->op.search.attrs,
348 paged_search_callback,
351 /* save it locally and remove it from the list */
352 /* we do not need to replace them later as we
353 * are keeping the original req intact */
354 if (!save_controls(control, search_req, &saved_controls)) {
355 return LDB_ERR_OPERATIONS_ERROR;
358 return ldb_next_request(module, search_req);
361 struct results_store *current = NULL;
363 /* TODO: age out old outstanding requests */
364 for (current = private_data->store; current; current = current->next) {
365 if (strcmp(current->cookie, paged_ctrl->cookie) == 0) {
366 current->timestamp = time(NULL);
370 if (current == NULL) {
371 return LDB_ERR_UNWILLING_TO_PERFORM;
376 /* check if it is an abandon */
378 return ldb_module_done(req, NULL, NULL,
382 ret = paged_results(ac);
383 if (ret != LDB_SUCCESS) {
384 return ldb_module_done(req, NULL, NULL, ret);
386 return ldb_module_done(req, ac->controls, NULL,
391 static int paged_request_init(struct ldb_module *module)
393 struct ldb_context *ldb;
394 struct private_data *data;
397 ldb = ldb_module_get_ctx(module);
399 data = talloc(module, struct private_data);
401 return LDB_ERR_OTHER;
404 data->next_free_id = 1;
406 ldb_module_set_private(module, data);
408 ret = ldb_mod_register_control(module, LDB_CONTROL_PAGED_RESULTS_OID);
409 if (ret != LDB_SUCCESS) {
410 ldb_debug(ldb, LDB_DEBUG_WARNING,
412 "Unable to register control with rootdse!\n");
415 return ldb_next_init(module);
418 const struct ldb_module_ops ldb_paged_results_module_ops = {
419 .name = "paged_results",
420 .search = paged_search,
421 .init_context = paged_request_init