1 files changed, 349 insertions, 0 deletions
diff --git a/source4/lib/ldb/modules/sort.c b/source4/lib/ldb/modules/sort.c
new file mode 100644
index 0000000000..309101c32b
--- /dev/null
+++ b/source4/lib/ldb/modules/sort.c
@@ -0,0 +1,349 @@
+/* 
+   ldb database library
+
+   Copyright (C) Simo Sorce  2005-2008
+
+     ** NOTE! The following LGPL license applies to the ldb
+     ** library. This does NOT imply that all of Samba is released
+     ** under the LGPL
+   
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+/*
+ *  Name: ldb
+ *
+ *  Component: ldb server side sort control module
+ *
+ *  Description: this module sorts the results of a search
+ *
+ *  Author: Simo Sorce
+ */
+
+#include "ldb_module.h"
+
+struct opaque {
+	struct ldb_context *ldb;
+	const struct ldb_attrib_handler *h;
+	const char *attribute;
+	int reverse;
+	int result;
+};
+
+struct sort_context {
+	struct ldb_module *module;
+
+	char *attributeName;
+	char *orderingRule;
+	int reverse;
+
+	struct ldb_request *req;
+	struct ldb_message **msgs;
+	char **referrals;
+	int num_msgs;
+	int num_refs;
+
+	const struct ldb_schema_attribute *a;
+	int sort_result;
+};
+
+static int build_response(void *mem_ctx, struct ldb_control ***ctrls, int result, const char *desc)
+{
+	struct ldb_control **controls;
+	struct ldb_sort_resp_control *resp;
+	int i;
+
+	if (*ctrls) {
+		controls = *ctrls;
+		for (i = 0; controls[i]; i++);
+		controls = talloc_realloc(mem_ctx, controls, struct ldb_control *, i + 2);
+	} else {
+		i = 0;
+		controls = talloc_array(mem_ctx, struct ldb_control *, 2);
+	}
+	if (! controls )
+		return LDB_ERR_OPERATIONS_ERROR;
+
+	*ctrls = controls;
+
+	controls[i+1] = NULL;
+	controls[i] = talloc(controls, struct ldb_control);
+	if (! controls[i] )
+		return LDB_ERR_OPERATIONS_ERROR;
+
+	controls[i]->oid = LDB_CONTROL_SORT_RESP_OID;
+	controls[i]->critical = 0;
+
+	resp = talloc(controls[i], struct ldb_sort_resp_control);
+	if (! resp )
+		return LDB_ERR_OPERATIONS_ERROR;
+
+	resp->result = result;
+	resp->attr_desc = talloc_strdup(resp, desc);
+
+	if (! resp->attr_desc )
+		return LDB_ERR_OPERATIONS_ERROR;
+	
+	controls[i]->data = resp;
+
+	return LDB_SUCCESS;
+}
+
+static int sort_compare(struct ldb_message **msg1, struct ldb_message **msg2, void *opaque)
+{
+	struct sort_context *ac = talloc_get_type(opaque, struct sort_context);
+	struct ldb_message_element *el1, *el2;
+	struct ldb_context *ldb;
+
+	ldb = ldb_module_get_ctx(ac->module);
+
+	if (ac->sort_result != 0) {
+		/* an error occurred previously,
+		 * let's exit the sorting by returning always 0 */
+		return 0;
+	}
+
+	el1 = ldb_msg_find_element(*msg1, ac->attributeName);
+	el2 = ldb_msg_find_element(*msg2, ac->attributeName);
+
+	if (!el1 || !el2) {
+		/* the attribute was not found return and
+		 * set an error */
+		ac->sort_result = LDB_ERR_UNWILLING_TO_PERFORM;
+		return 0;
+	}
+
+	if (ac->reverse)
+		return ac->a->syntax->comparison_fn(ldb, ac, &el2->values[0], &el1->values[0]);
+
+	return ac->a->syntax->comparison_fn(ldb, ac, &el1->values[0], &el2->values[0]);
+}
+
+static int server_sort_results(struct sort_context *ac)
+{
+	struct ldb_context *ldb;
+	struct ldb_reply *ares;
+	int i, ret;
+
+	ldb = ldb_module_get_ctx(ac->module);
+
+	ac->a = ldb_schema_attribute_by_name(ldb, ac->attributeName);
+	ac->sort_result = 0;
+
+	ldb_qsort(ac->msgs, ac->num_msgs,
+		  sizeof(struct ldb_message *),
+		  ac, (ldb_qsort_cmp_fn_t)sort_compare);
+
+	if (ac->sort_result != LDB_SUCCESS) {
+		return ac->sort_result;
+	}
+
+	for (i = 0; i < ac->num_msgs; i++) {
+		ares = talloc_zero(ac, struct ldb_reply);
+		if (!ares) {
+			return LDB_ERR_OPERATIONS_ERROR;
+		}
+
+		ares->type = LDB_REPLY_ENTRY;
+		ares->message = talloc_move(ares, &ac->msgs[i]);
+
+		ret = ldb_module_send_entry(ac->req, ares->message, ares->controls);
+		if (ret != LDB_SUCCESS) {
+			return ret;
+		}
+	}
+
+	for (i = 0; i < ac->num_refs; i++) {
+		ares = talloc_zero(ac, struct ldb_reply);
+		if (!ares) {
+			return LDB_ERR_OPERATIONS_ERROR;
+		}
+
+		ares->type = LDB_REPLY_REFERRAL;
+		ares->referral = talloc_move(ares, &ac->referrals[i]);
+
+		ret = ldb_module_send_referral(ac->req, ares->referral);
+		if (ret != LDB_SUCCESS) {
+			return ret;
+		}
+	}
+
+	return LDB_SUCCESS;
+}
+
+static int server_sort_search_callback(struct ldb_request *req, struct ldb_reply *ares)
+{
+	struct sort_context *ac;
+	struct ldb_context *ldb;
+	int ret;
+
+	ac = talloc_get_type(req->context, struct sort_context);
+	ldb = ldb_module_get_ctx(ac->module);
+
+	if (!ares) {
+		return ldb_module_done(ac->req, NULL, NULL,
+					LDB_ERR_OPERATIONS_ERROR);
+	}
+	if (ares->error != LDB_SUCCESS) {
+		return ldb_module_done(ac->req, ares->controls,
+					ares->response, ares->error);
+	}
+
+	switch (ares->type) {
+	case LDB_REPLY_ENTRY:
+		ac->msgs = talloc_realloc(ac, ac->msgs, struct ldb_message *, ac->num_msgs + 2);
+		if (! ac->msgs) {
+			talloc_free(ares);
+			ldb_oom(ldb);
+			return ldb_module_done(ac->req, NULL, NULL,
+						LDB_ERR_OPERATIONS_ERROR);
+		}
+
+		ac->msgs[ac->num_msgs] = talloc_steal(ac->msgs, ares->message);
+		ac->num_msgs++;
+		ac->msgs[ac->num_msgs] = NULL;
+
+		break;
+
+	case LDB_REPLY_REFERRAL:
+		ac->referrals = talloc_realloc(ac, ac->referrals, char *, ac->num_refs + 2);
+		if (! ac->referrals) {
+			talloc_free(ares);
+			ldb_oom(ldb);
+			return ldb_module_done(ac->req, NULL, NULL,
+						LDB_ERR_OPERATIONS_ERROR);
+		}
+
+		ac->referrals[ac->num_refs] = talloc_steal(ac->referrals, ares->referral);
+		ac->num_refs++;
+		ac->referrals[ac->num_refs] = NULL;
+
+		break;
+
+	case LDB_REPLY_DONE:
+
+		ret = server_sort_results(ac);
+		return ldb_module_done(ac->req, ares->controls,
+					ares->response, ret);
+	}
+
+	talloc_free(ares);
+	return LDB_SUCCESS;
+}
+
+static int server_sort_search(struct ldb_module *module, struct ldb_request *req)
+{
+	struct ldb_control *control;
+	struct ldb_server_sort_control **sort_ctrls;
+	struct ldb_control **saved_controls;
+	struct ldb_control **controls;
+	struct ldb_request *down_req;
+	struct sort_context *ac;
+	struct ldb_context *ldb;
+	int ret;
+
+	ldb = ldb_module_get_ctx(module);
+
+	/* check if there's a paged request control */
+	control = ldb_request_get_control(req, LDB_CONTROL_SERVER_SORT_OID);
+	if (control == NULL) {
+		/* not found go on */
+		return ldb_next_request(module, req);
+	}
+
+	ac = talloc_zero(req, struct sort_context);
+	if (ac == NULL) {
+		ldb_oom(ldb);
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	ac->module = module;
+	ac->req = req;
+
+	sort_ctrls = talloc_get_type(control->data, struct ldb_server_sort_control *);
+	if (!sort_ctrls) {
+		return LDB_ERR_PROTOCOL_ERROR;
+	}
+
+	/* FIXME: we do not support more than one attribute for sorting right now */
+	/* FIXME: we need to check if the attribute type exist or return an error */
+		
+	if (sort_ctrls[1] != NULL) {
+		if (control->critical) {
+
+			/* callback immediately */
+			ret = build_response(req, &controls,
+					     LDB_ERR_UNWILLING_TO_PERFORM,
+					     "sort control is not complete yet");
+			if (ret != LDB_SUCCESS) {
+				return ldb_module_done(req, NULL, NULL,
+						    LDB_ERR_OPERATIONS_ERROR);
+			}
+
+			return ldb_module_done(req, controls, NULL, ret);
+		} else {
+			/* just pass the call down and don't do any sorting */
+			return ldb_next_request(module, req);
+		}
+	}
+
+	ac->attributeName = sort_ctrls[0]->attributeName;
+	ac->orderingRule = sort_ctrls[0]->orderingRule;
+	ac->reverse = sort_ctrls[0]->reverse;
+
+	ret = ldb_build_search_req_ex(&down_req, ldb, ac,
+					req->op.search.base,
+					req->op.search.scope,
+					req->op.search.tree,
+					req->op.search.attrs,
+					req->controls,
+					ac,
+					server_sort_search_callback,
+					req);
+	if (ret != LDB_SUCCESS) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	/* save it locally and remove it from the list */
+	/* we do not need to replace them later as we
+	 * are keeping the original req intact */
+	if (!save_controls(control, down_req, &saved_controls)) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	return ldb_next_request(module, down_req);
+}
+
+static int server_sort_init(struct ldb_module *module)
+{
+	struct ldb_context *ldb;
+	int ret;
+
+	ldb = ldb_module_get_ctx(module);
+
+	ret = ldb_mod_register_control(module, LDB_CONTROL_SERVER_SORT_OID);
+	if (ret != LDB_SUCCESS) {
+		ldb_debug(ldb, LDB_DEBUG_WARNING,
+			"server_sort:"
+			"Unable to register control with rootdse!\n");
+	}
+
+	return ldb_next_init(module);
+}
+
+const struct ldb_module_ops ldb_server_sort_module_ops = {
+	.name		   = "server_sort",
+	.search            = server_sort_search,
+	.init_context	   = server_sort_init
+};