[evolution-data-server] Bug #661448 - e_util_copy_*_slist(): Avoid using append function

[Christophe Dumez <cdumez src gnome org>]

commit 05623005c5be50413e2410525d0b7cc682cda25c
Author: Christophe Dumez <christophe dumez intel com>
Date:   Tue Oct 11 14:02:57 2011 +0300

    Bug #661448 - e_util_copy_*_slist(): Avoid using append function
    
    The current implementation calls g_slist_append() for each element
    of the list to copy. However, g_slist_append() is expensive
    because it iterate over the whole destination list.
    
    This patch alters the behavior to first make a deep copy of the
    list and then concatenate the destination list and the list copy.
    The concatenation only iterates of the destination list once.

 libedataserver/e-data-server-util.c |   32 ++++++++++++++++++++------------
 1 files changed, 20 insertions(+), 12 deletions(-)
---
diff --git a/libedataserver/e-data-server-util.c b/libedataserver/e-data-server-util.c
index 764fa09..94d2177 100644
--- a/libedataserver/e-data-server-util.c
+++ b/libedataserver/e-data-server-util.c
@@ -870,14 +870,18 @@ GSList *
 e_util_copy_string_slist (GSList *copy_to,
                           const GSList *strings)
 {
-	GSList *res = copy_to;
-	const GSList *iter;
-
-	for (iter = strings; iter; iter = iter->next) {
-		res = g_slist_append (res, g_strdup (iter->data));
+	if (strings != NULL) {
+		const GSList *iter;
+		GSList *strings_copy = NULL;
+		/* Make deep copy of strings */
+		for (iter = strings; iter; iter = iter->next)
+			strings_copy = g_slist_prepend (strings_copy, g_strdup (iter->data));
+
+		/* Concatenate the two lists */
+		return g_slist_concat (copy_to, g_slist_reverse (strings_copy));
 	}
 
-	return res;
+	return copy_to;
 }
 
 /**
@@ -896,14 +900,18 @@ GSList *
 e_util_copy_object_slist (GSList *copy_to,
                           const GSList *objects)
 {
-	GSList *res = copy_to;
-	const GSList *iter;
-
-	for (iter = objects; iter; iter = iter->next) {
-		res = g_slist_append (res, g_object_ref (iter->data));
+	if (objects != NULL) {
+		const GSList *iter;
+		GSList *objects_copy = NULL;
+		/* Make deep copy of objects */
+		for (iter = objects; iter; iter = iter->next)
+			objects_copy = g_slist_prepend (objects_copy, g_object_ref (iter->data));
+
+		/* Concatenate the two lists */
+		return g_slist_concat (copy_to, g_slist_reverse (objects_copy));
 	}
 
-	return res;
+	return copy_to;
 }
 
 /**