s4:ldb Add a helper function for 'canonicalise' both strings base compares

This will help simplify boilerplate comparison functions where we
don't have a shortcut way to compare.

Andrew Bartlett

2 files changed, 33 insertions, 0 deletions

diff --git a/source4/lib/ldb/common/attrib_handlers.c b/source4/lib/ldb/common/attrib_handlers.c
index ba21fcac9b..1c08741f7d 100644
--- a/source4/lib/ldb/common/attrib_handlers.c
+++ b/source4/lib/ldb/common/attrib_handlers.c
@@ -2,6 +2,7 @@
    ldb database library
 
    Copyright (C) Andrew Tridgell  2005
+   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2006-2009
 
      ** NOTE! The following LGPL license applies to the ldb
      ** library. This does NOT imply that all of Samba is released
@@ -430,3 +431,29 @@ const struct ldb_schema_syntax *ldb_standard_syntax_by_name(struct ldb_context *
 	}
 	return NULL;
 }
+
+int ldb_any_comparison(struct ldb_context *ldb, void *mem_ctx, 
+		       ldb_attr_handler_t canonicalise_fn, 
+		       const struct ldb_val *v1,
+		       const struct ldb_val *v2)
+{
+	int ret, ret1, ret2;
+	struct ldb_val v1_canon, v2_canon;
+	TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
+
+	/* I could try and bail if tmp_ctx was NULL, but what return
+	 * value would I use?
+	 *
+	 * It seems easier to continue on the NULL context 
+	 */
+	ret1 = canonicalise_fn(ldb, tmp_ctx, v1, &v1_canon);
+	ret2 = canonicalise_fn(ldb, tmp_ctx, v2, &v2_canon);
+
+	if (ret1 == LDB_SUCCESS && ret2 == LDB_SUCCESS) {
+		ret = ldb_comparison_binary(ldb, mem_ctx, &v1_canon, &v2_canon);
+	} else {
+		ret = ldb_comparison_binary(ldb, mem_ctx, v1, v2);
+	}
+	talloc_free(tmp_ctx);
+	return ret;
+}
diff --git a/source4/lib/ldb/include/ldb_module.h b/source4/lib/ldb/include/ldb_module.h
index 977d485ada..7c18683201 100644
--- a/source4/lib/ldb/include/ldb_module.h
+++ b/source4/lib/ldb/include/ldb_module.h
@@ -99,6 +99,12 @@ void ldb_schema_attribute_set_override_handler(struct ldb_context *ldb,
 					       ldb_attribute_handler_override_fn_t override,
 					       void *private_data);
 
+/* A useful function to build comparison functions with */
+int ldb_any_comparison(struct ldb_context *ldb, void *mem_ctx, 
+		       ldb_attr_handler_t canonicalise_fn, 
+		       const struct ldb_val *v1,
+		       const struct ldb_val *v2);
+
 /* The following definitions come from lib/ldb/common/ldb_controls.c  */
 struct ldb_control *get_control_from_list(struct ldb_control **controls, const char *oid);
 int save_controls(struct ldb_control *exclude, struct ldb_request *req, struct ldb_control ***saver);