getncchanges.c: Split sorting linked attributes into separate function

Longer-term we want to split up the links so that they're sent over
multiple GetNCChanges response messages. So it makes sense to split this
code out into its own function. In the short-term, this removes some of
the complexity from dcesrv_drsuapi_DsGetNCChanges() so that the function
is not quite so big.

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

diff --git a/source4/rpc_server/drsuapi/getncchanges.c b/source4/rpc_server/drsuapi/getncchanges.c
index 7acab667a24682f058b7232b7abc8ae1550762ca..9905ad9b48927f5609580c16de7ba84bbff176af 100644 (file)
--- a/source4/rpc_server/drsuapi/getncchanges.c
+++ b/source4/rpc_server/drsuapi/getncchanges.c
@@ -69,7 +69,7 @@ struct drsuapi_getncchanges_state {
 
 /* We must keep the GUIDs in NDR form for sorting */
 struct la_for_sorting {
-       struct drsuapi_DsReplicaLinkedAttribute *link;
+       const struct drsuapi_DsReplicaLinkedAttribute *link;
        uint8_t target_guid[16];
         uint8_t source_guid[16];
 };
@@ -2007,6 +2007,82 @@ static WERROR dcesrv_drsuapi_obj_cache_exists(struct db_context *obj_cache,
        return WERR_OBJECT_NAME_EXISTS;
 }
 
+/**
+ * Copies the la_list specified into a sorted array, ready to be sent in a
+ * GetNCChanges response.
+ */
+static WERROR getncchanges_get_sorted_array(const struct drsuapi_DsReplicaLinkedAttribute *la_list,
+                                           const uint32_t link_count,
+                                           struct ldb_context *sam_ctx,
+                                           TALLOC_CTX *mem_ctx,
+                                           const struct dsdb_schema *schema,
+                                           struct la_for_sorting **ret_array)
+{
+       int j;
+       struct la_for_sorting *guid_array;
+       WERROR werr = WERR_OK;
+
+       *ret_array = NULL;
+       guid_array = talloc_array(mem_ctx, struct la_for_sorting, link_count);
+       if (guid_array == NULL) {
+               DEBUG(0, ("Out of memory allocating %u linked attributes for sorting", link_count));
+               return WERR_NOT_ENOUGH_MEMORY;
+       }
+
+       for (j = 0; j < link_count; j++) {
+
+               /* we need to get the target GUIDs to compare */
+               struct dsdb_dn *dn;
+               const struct drsuapi_DsReplicaLinkedAttribute *la = &la_list[j];
+               const struct dsdb_attribute *schema_attrib;
+               const struct ldb_val *target_guid;
+               DATA_BLOB source_guid;
+               TALLOC_CTX *frame = talloc_stackframe();
+               NTSTATUS status;
+
+               schema_attrib = dsdb_attribute_by_attributeID_id(schema, la->attid);
+
+               werr = dsdb_dn_la_from_blob(sam_ctx, schema_attrib, schema, frame, la->value.blob, &dn);
+               if (!W_ERROR_IS_OK(werr)) {
+                       DEBUG(0,(__location__ ": Bad la blob in sort\n"));
+                       TALLOC_FREE(frame);
+                       return werr;
+               }
+
+               /* Extract the target GUID in NDR form */
+               target_guid = ldb_dn_get_extended_component(dn->dn, "GUID");
+               if (target_guid == NULL
+                               || target_guid->length != sizeof(guid_array[0].target_guid)) {
+                       status = NT_STATUS_OBJECT_NAME_NOT_FOUND;
+               } else {
+                       /* Repack the source GUID as NDR for sorting */
+                       status = GUID_to_ndr_blob(&la->identifier->guid,
+                                                 frame,
+                                                 &source_guid);
+               }
+
+               if (!NT_STATUS_IS_OK(status)
+                               || source_guid.length != sizeof(guid_array[0].source_guid)) {
+                       DEBUG(0,(__location__ ": Bad la guid in sort\n"));
+                       TALLOC_FREE(frame);
+                       return ntstatus_to_werror(status);
+               }
+
+               guid_array[j].link = &la_list[j];
+               memcpy(guid_array[j].target_guid, target_guid->data,
+                      sizeof(guid_array[j].target_guid));
+               memcpy(guid_array[j].source_guid, source_guid.data,
+                      sizeof(guid_array[j].source_guid));
+               TALLOC_FREE(frame);
+       }
+
+       LDB_TYPESAFE_QSORT(guid_array, link_count, NULL, linked_attribute_compare);
+
+       *ret_array = guid_array;
+
+       return werr;
+}
+
 /* 
   drsuapi_DsGetNCChanges
 
@@ -2925,59 +3001,14 @@ allowed:
        } else {
                /* sort the whole array the first time */
                if (getnc_state->la_sorted == NULL) {
-                       int j;
-                       struct la_for_sorting *guid_array = talloc_array(getnc_state, struct la_for_sorting, getnc_state->la_count);
-                       if (guid_array == NULL) {
-                               DEBUG(0, ("Out of memory allocating %u linked attributes for sorting", getnc_state->la_count));
-                               return WERR_NOT_ENOUGH_MEMORY;
-                       }
-                       for (j = 0; j < getnc_state->la_count; j++) {
-                               /* we need to get the target GUIDs to compare */
-                               struct dsdb_dn *dn;
-                               const struct drsuapi_DsReplicaLinkedAttribute *la = &getnc_state->la_list[j];
-                               const struct dsdb_attribute *schema_attrib;
-                               const struct ldb_val *target_guid;
-                               DATA_BLOB source_guid;
-                               TALLOC_CTX *frame = talloc_stackframe();
-
-                               schema_attrib = dsdb_attribute_by_attributeID_id(schema, la->attid);
-
-                               werr = dsdb_dn_la_from_blob(sam_ctx, schema_attrib, schema, frame, la->value.blob, &dn);
-                               if (!W_ERROR_IS_OK(werr)) {
-                                       DEBUG(0,(__location__ ": Bad la blob in sort\n"));
-                                       TALLOC_FREE(frame);
-                                       return werr;
-                               }
-
-                               /* Extract the target GUID in NDR form */
-                               target_guid = ldb_dn_get_extended_component(dn->dn, "GUID");
-                               if (target_guid == NULL
-                                   || target_guid->length != sizeof(guid_array[0].target_guid)) {
-                                       status = NT_STATUS_OBJECT_NAME_NOT_FOUND;
-                               } else {
-                                       /* Repack the source GUID as NDR for sorting */
-                                       status = GUID_to_ndr_blob(&la->identifier->guid,
-                                                                 frame,
-                                                                 &source_guid);
-                               }
-
-                               if (!NT_STATUS_IS_OK(status)
-                                   || source_guid.length != sizeof(guid_array[0].source_guid)) {
-                                       DEBUG(0,(__location__ ": Bad la guid in sort\n"));
-                                       TALLOC_FREE(frame);
-                                       return ntstatus_to_werror(status);
-                               }
-
-                               guid_array[j].link = &getnc_state->la_list[j];
-                               memcpy(guid_array[j].target_guid, target_guid->data,
-                                      sizeof(guid_array[j].target_guid));
-                               memcpy(guid_array[j].source_guid, source_guid.data,
-                                      sizeof(guid_array[j].source_guid));
-                               TALLOC_FREE(frame);
+                       werr = getncchanges_get_sorted_array(getnc_state->la_list,
+                                                            getnc_state->la_count,
+                                                            sam_ctx, getnc_state,
+                                                            schema,
+                                                            &getnc_state->la_sorted);
+                       if (!W_ERROR_IS_OK(werr)) {
+                               return werr;
                        }
-
-                       LDB_TYPESAFE_QSORT(guid_array, getnc_state->la_count, NULL, linked_attribute_compare);
-                       getnc_state->la_sorted = guid_array;
                }
 
                link_count = getnc_state->la_count - getnc_state->la_idx;