dsdb: linked_attributes module knows about sorted links

Until now the linked attrbutes module has allocated its private data
on a per transaction basis, but we prefer to check the sorted links
feature less often than that. So the private data struct is given
module life time and a transaction member to carry out the old role.

In coming patches, the sorted links flag will be used.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

diff --git a/source4/dsdb/samdb/ldb_modules/linked_attributes.c b/source4/dsdb/samdb/ldb_modules/linked_attributes.c
index 4fd1209a46b2cf5c2e48ec595520c09a6ea6a44e..41c8afbbac07de4c8e4f18bc525880c76a7639c8 100644 (file)
--- a/source4/dsdb/samdb/ldb_modules/linked_attributes.c
+++ b/source4/dsdb/samdb/ldb_modules/linked_attributes.c
@@ -53,10 +53,17 @@
 #include "librpc/gen_ndr/ndr_misc.h"
 #include "dsdb/samdb/ldb_modules/util.h"
 
-struct la_private {
+
+struct la_private_transaction {
        struct la_context *la_list;
 };
 
+
+struct la_private {
+       struct la_private_transaction *transaction;
+       bool sorted_links;
+};
+
 struct la_op_store {
        struct la_op_store *next;
        struct la_op_store *prev;
@@ -936,15 +943,18 @@ static int linked_attributes_rename(struct ldb_module *module, struct ldb_reques
 static int la_queue_mod_request(struct la_context *ac)
 {
        struct la_private *la_private =
-               talloc_get_type(ldb_module_get_private(ac->module), struct la_private);
+               talloc_get_type(ldb_module_get_private(ac->module),
+                               struct la_private);
 
-       if (la_private == NULL) {
-               ldb_debug(ldb_module_get_ctx(ac->module), LDB_DEBUG_ERROR, __location__ ": No la_private transaction setup\n");
+       if (la_private == NULL || la_private->transaction == NULL) {
+               ldb_debug(ldb_module_get_ctx(ac->module),
+                         LDB_DEBUG_ERROR,
+                         __location__ ": No la_private transaction setup\n");
                return ldb_operr(ldb_module_get_ctx(ac->module));
        }
 
-       talloc_steal(la_private, ac);
-       DLIST_ADD(la_private->la_list, ac);
+       talloc_steal(la_private->transaction, ac);
+       DLIST_ADD(la_private->transaction->la_list, ac);
 
        return ldb_module_done(ac->req, ac->op_controls,
                               ac->op_response, LDB_SUCCESS);
@@ -1209,15 +1219,19 @@ static int la_do_mod_request(struct ldb_module *module, struct la_context *ac)
 static int linked_attributes_start_transaction(struct ldb_module *module)
 {
        /* create our private structure for this transaction */
-       struct la_private *la_private = talloc_get_type(ldb_module_get_private(module),
-                                                       struct la_private);
-       talloc_free(la_private);
-       la_private = talloc(module, struct la_private);
+       struct la_private *la_private =
+               talloc_get_type(ldb_module_get_private(module),
+                               struct la_private);
+
        if (la_private == NULL) {
                return ldb_oom(ldb_module_get_ctx(module));
        }
-       la_private->la_list = NULL;
-       ldb_module_set_private(module, la_private);
+       talloc_free(la_private->transaction);
+       la_private->transaction = talloc(module, struct la_private_transaction);
+       if (la_private->transaction == NULL) {
+               return ldb_oom(ldb_module_get_ctx(module));
+       }
+       la_private->transaction->la_list = NULL;
        return ldb_next_start_trans(module);
 }
 
@@ -1227,12 +1241,14 @@ static int linked_attributes_start_transaction(struct ldb_module *module)
  */
 static int linked_attributes_prepare_commit(struct ldb_module *module)
 {
-       struct la_private *la_private =
-               talloc_get_type(ldb_module_get_private(module), struct la_private);
        struct la_context *ac;
-
-       if (!la_private) {
-               /* prepare commit without begin_transaction - let someone else return the error, just don't segfault */
+       struct la_private *la_private =
+               talloc_get_type(ldb_module_get_private(module),
+                               struct la_private);
+       if (la_private == NULL || la_private->transaction == NULL) {
+               DBG_ERR("prepare_commit without begin_transaction\n");
+               /* prepare commit without begin_transaction - let someone else
+                * return the error, just don't segfault */
                return ldb_next_prepare_commit(module);
        }
        /* walk the list backwards, to do the first entry first, as we
@@ -1242,7 +1258,7 @@ static int linked_attributes_prepare_commit(struct ldb_module *module)
        /* Start at the end of the list - so we can start
         * there, but ensure we don't create a loop by NULLing
         * it out in the first element */
-       ac = DLIST_TAIL(la_private->la_list);
+       ac = DLIST_TAIL(la_private->transaction->la_list);
 
        for (; ac; ac=DLIST_PREV(ac)) {
                int ret;
@@ -1250,14 +1266,12 @@ static int linked_attributes_prepare_commit(struct ldb_module *module)
                ret = la_do_mod_request(module, ac);
                if (ret != LDB_SUCCESS) {
                        DEBUG(0,(__location__ ": Failed mod request ret=%d\n", ret));
-                       talloc_free(la_private);
-                       ldb_module_set_private(module, NULL);
+                       TALLOC_FREE(la_private->transaction);
                        return ret;
                }
        }
 
-       talloc_free(la_private);
-       ldb_module_set_private(module, NULL);
+       TALLOC_FREE(la_private->transaction);
 
        return ldb_next_prepare_commit(module);
 }
@@ -1265,15 +1279,17 @@ static int linked_attributes_prepare_commit(struct ldb_module *module)
 static int linked_attributes_del_transaction(struct ldb_module *module)
 {
        struct la_private *la_private =
-               talloc_get_type(ldb_module_get_private(module), struct la_private);
-       talloc_free(la_private);
-       ldb_module_set_private(module, NULL);
+               talloc_get_type(ldb_module_get_private(module),
+                               struct la_private);
+       TALLOC_FREE(la_private->transaction);
        return ldb_next_del_trans(module);
 }
 
 static int linked_attributes_ldb_init(struct ldb_module *module)
 {
        int ret;
+       struct la_private *la_private = NULL;
+       struct ldb_context *ldb = ldb_module_get_ctx(module);
 
        ret = ldb_mod_register_control(module, LDB_CONTROL_VERIFY_NAME_OID);
        if (ret != LDB_SUCCESS) {
@@ -1282,6 +1298,21 @@ static int linked_attributes_ldb_init(struct ldb_module *module)
                return ldb_operr(ldb_module_get_ctx(module));
        }
 
+       la_private = talloc_zero(module, struct la_private);
+       if (la_private == NULL) {
+               ldb_oom(ldb);
+               return LDB_ERR_OPERATIONS_ERROR;
+       }
+
+       ret = dsdb_check_samba_compatible_feature(module,
+                                                 SAMBA_SORTED_LINKS_FEATURE,
+                                                 &la_private->sorted_links);
+       if (ret != LDB_SUCCESS) {
+               talloc_free(la_private);
+               return ret;
+       }
+
+       ldb_module_set_private(module, la_private);
        return ldb_next_init(module);
 }