5 Copyright (C) Simo Sorce 2004
7 ** NOTE! The following LGPL license applies to the ldb
8 ** library. This does NOT imply that all of Samba is released
11 This library is free software; you can redistribute it and/or
12 modify it under the terms of the GNU Lesser General Public
13 License as published by the Free Software Foundation; either
14 version 2 of the License, or (at your option) any later version.
16 This library is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 Lesser General Public License for more details.
21 You should have received a copy of the GNU Lesser General Public
22 License along with this library; if not, write to the Free Software
23 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
29 * Component: ldb modules core
31 * Description: core modules routines
37 #include "ldb/include/includes.h"
43 #define LDB_MODULE_PREFIX "modules:"
44 #define LDB_MODULE_PREFIX_LEN 8
46 static char *talloc_strdup_no_spaces(struct ldb_context *ldb, const char *string)
51 trimmed = talloc_strdup(ldb, string);
53 ldb_debug(ldb, LDB_DEBUG_FATAL, "Out of Memory in talloc_strdup_trim_spaces()\n");
57 len = strlen(trimmed);
58 for (i = 0; trimmed[i] != '\0'; i++) {
63 memmove(&trimmed[i], &trimmed[i + 1], len -i -1);
72 /* modules are called in inverse order on the stack.
73 Lets place them as an admin would think the right order is.
74 Modules order is important */
75 static char **ldb_modules_list_from_string(struct ldb_context *ldb, const char *string)
77 char **modules = NULL;
81 /* spaces not admitted */
82 modstr = talloc_strdup_no_spaces(ldb, string);
87 modules = talloc_realloc(ldb, modules, char *, 2);
89 ldb_debug(ldb, LDB_DEBUG_FATAL, "Out of Memory in ldb_modules_list_from_string()\n");
93 talloc_steal(modules, modstr);
96 while ((p = strrchr(modstr, ',')) != NULL) {
102 modules = talloc_realloc(ldb, modules, char *, i + 2);
104 ldb_debug(ldb, LDB_DEBUG_FATAL, "Out of Memory in ldb_modules_list_from_string()\n");
111 modules[i + 1] = NULL;
116 static struct ops_list_entry {
117 const struct ldb_module_ops *ops;
118 struct ops_list_entry *next;
119 } *registered_modules = NULL;
121 static const struct ldb_module_ops *ldb_find_module_ops(const char *name)
123 struct ops_list_entry *e;
125 for (e = registered_modules; e; e = e->next) {
126 if (strcmp(e->ops->name, name) == 0)
134 #define LDAP_INIT ldb_ldap_init,
140 #define SQLITE3_INIT ldb_sqlite3_init,
145 #ifndef STATIC_ldb_MODULES
146 #define STATIC_ldb_MODULES \
152 ldb_operational_init, \
154 ldb_objectclass_init, \
155 ldb_paged_results_init, \
161 int ldb_global_init(void)
163 static int (*static_init_fns[])(void) = STATIC_ldb_MODULES;
165 static int initialized = 0;
173 for (i = 0; static_init_fns[i]; i++) {
174 if (static_init_fns[i]() == -1)
181 int ldb_register_module(const struct ldb_module_ops *ops)
183 struct ops_list_entry *entry = talloc(talloc_autofree_context(), struct ops_list_entry);
185 if (ldb_find_module_ops(ops->name) != NULL)
192 entry->next = registered_modules;
193 registered_modules = entry;
198 int ldb_try_load_dso(struct ldb_context *ldb, const char *name)
202 int (*init_fn) (void);
205 path = talloc_asprintf(ldb, "%s/%s.%s", MODULESDIR, name, SHLIBEXT);
207 ldb_debug(ldb, LDB_DEBUG_TRACE, "trying to load %s from %s\n", name, path);
209 handle = dlopen(path, 0);
210 if (handle == NULL) {
211 ldb_debug(ldb, LDB_DEBUG_WARNING, "unable to load %s from %s: %s\n", name, path, dlerror());
215 init_fn = dlsym(handle, "init_module");
217 if (init_fn == NULL) {
218 ldb_debug(ldb, LDB_DEBUG_ERROR, "no symbol `init_module' found in %s: %s\n", path, dlerror());
226 ldb_debug(ldb, LDB_DEBUG_TRACE, "no dlopen() - not trying to load %s module\n", name);
231 int ldb_load_modules(struct ldb_context *ldb, const char *options[])
233 char **modules = NULL;
234 struct ldb_module *module;
236 /* find out which modules we are requested to activate */
238 /* check if we have a custom module list passd as ldb option */
240 for (i = 0; options[i] != NULL; i++) {
241 if (strncmp(options[i], LDB_MODULE_PREFIX, LDB_MODULE_PREFIX_LEN) == 0) {
242 modules = ldb_modules_list_from_string(ldb, &options[i][LDB_MODULE_PREFIX_LEN]);
247 /* if not overloaded by options and the backend is not ldap try to load the modules list from ldb */
248 if ((modules == NULL) && (strcmp("ldap", ldb->modules->ops->name) != 0)) {
250 const char * const attrs[] = { "@LIST" , NULL};
251 struct ldb_result *res = NULL;
254 mods = ldb_dn_explode(ldb, "@MODULES");
259 ret = ldb_search(ldb, mods, LDB_SCOPE_BASE, "", attrs, &res);
261 if (ret == LDB_SUCCESS && (res->count == 0 || res->msgs[0]->num_elements == 0)) {
262 ldb_debug(ldb, LDB_DEBUG_TRACE, "no modules required by the db\n");
264 if (ret != LDB_SUCCESS) {
265 ldb_debug(ldb, LDB_DEBUG_FATAL, "ldb error (%s) occurred searching for modules, bailing out\n", ldb_errstring(ldb));
268 if (res->count > 1) {
269 ldb_debug(ldb, LDB_DEBUG_FATAL, "Too many records found (%d), bailing out\n", res->count);
274 modules = ldb_modules_list_from_string(ldb,
275 (const char *)res->msgs[0]->elements[0].values[0].data);
282 if (modules != NULL) {
283 for (i = 0; modules[i] != NULL; i++) {
284 struct ldb_module *current;
285 const struct ldb_module_ops *ops;
287 ops = ldb_find_module_ops(modules[i]);
289 if (ldb_try_load_dso(ldb, modules[i]) == 0) {
290 ops = ldb_find_module_ops(modules[i]);
295 ldb_debug(ldb, LDB_DEBUG_WARNING, "WARNING: Module [%s] not found\n",
300 current = talloc_zero(ldb, struct ldb_module);
301 if (current == NULL) {
308 DLIST_ADD(ldb->modules, current);
311 talloc_free(modules);
313 ldb_debug(ldb, LDB_DEBUG_TRACE, "No modules specified for this database\n");
316 module = ldb->modules;
318 while (module && module->ops->init_context == NULL)
319 module = module->next;
321 if (module && module->ops->init_context &&
322 module->ops->init_context(module) != LDB_SUCCESS) {
323 ldb_debug(ldb, LDB_DEBUG_FATAL, "module initialization failed\n");
331 by using this we allow ldb modules to only implement the functions they care about,
332 which makes writing a module simpler, and makes it more likely to keep working
335 #define FIND_OP(module, op) do { \
336 module = module->next; \
337 while (module && module->ops->op == NULL) module = module->next; \
338 if (module == NULL) return LDB_ERR_OPERATIONS_ERROR; \
343 helper functions to call the next module in chain
345 int ldb_next_request(struct ldb_module *module, struct ldb_request *request)
347 FIND_OP(module, request);
348 return module->ops->request(module, request);
351 int ldb_next_init(struct ldb_module *module)
353 /* init is different in that it is not an error if modules
354 * do not require initialization */
356 module = module->next;
358 while (module && module->ops->init_context == NULL)
359 module = module->next;
364 return module->ops->init_context(module);
367 int ldb_next_start_trans(struct ldb_module *module)
369 FIND_OP(module, start_transaction);
370 return module->ops->start_transaction(module);
373 int ldb_next_end_trans(struct ldb_module *module)
375 FIND_OP(module, end_transaction);
376 return module->ops->end_transaction(module);
379 int ldb_next_del_trans(struct ldb_module *module)
381 FIND_OP(module, del_transaction);
382 return module->ops->del_transaction(module);