uci: optimize update option in uci_set

Optimize for the case when there is no need to reallocate memory when
updating an option in uci_set.

Signed-off-by: Jan Venekamp <jan@venekamp.net>

diff --git a/list.c b/list.c
index a8f2a2cd0f913752f6b403178524460b64b2aca8..5148dfd939ee7451a42a46b0fc730999eff39288 100644 (file)
--- a/list.c
+++ b/list.c
@@ -725,17 +725,19 @@ int uci_set(struct uci_context *ctx, struct uci_ptr *ptr)
                ptr->s = uci_alloc_section(ptr->p, ptr->value, ptr->section);
                ptr->last = &ptr->s->e;
        } else if (ptr->o && ptr->option) { /* update option */
-               struct uci_option *old = ptr->o;
-
-               if ((ptr->o->type == UCI_TYPE_STRING) &&
-                       !strcmp(ptr->o->v.string, ptr->value))
+               if (ptr->o->type == UCI_TYPE_STRING && !strcmp(ptr->o->v.string, ptr->value))
                        return 0;
 
-               ptr->o = uci_alloc_option(ptr->s, ptr->option, ptr->value, &old->e.list);
-               if (ptr->option == old->e.name)
-                       ptr->option = ptr->o->e.name;
-               uci_free_option(old);
-               ptr->last = &ptr->o->e;
+               if (ptr->o->type == UCI_TYPE_STRING && strlen(ptr->o->v.string) == strlen(ptr->value)) {
+                       strcpy(ptr->o->v.string, ptr->value);
+               } else {
+                       struct uci_option *old = ptr->o;
+                       ptr->o = uci_alloc_option(ptr->s, ptr->option, ptr->value, &old->e.list);
+                       if (ptr->option == old->e.name)
+                               ptr->option = ptr->o->e.name;
+                       uci_free_option(old);
+                       ptr->last = &ptr->o->e;
+               }
        } else if (ptr->s && ptr->section) { /* update section */
                char *s = uci_strdup(ctx, ptr->value);