control: remap - add no-op when the remapping is not active

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

diff --git a/src/control/control_remap.c b/src/control/control_remap.c
index 4824259..f3d6501 100644 (file)
--- a/src/control/control_remap.c
+++ b/src/control/control_remap.c
@@ -1170,6 +1170,13 @@ int snd_ctl_remap_open(snd_ctl_t **handlep, const char *name, snd_config_t *rema
                goto _err;
        }
 
+       /* no-op check, remove the plugin */
+       if (priv->map_items == 0 && priv->remap_items == 0) {
+               remap_free(priv);
+               *handlep = child;
+               return 0;
+       }
+
        priv->map_read_queue = calloc(priv->map_items, sizeof(priv->map_read_queue[0]));
        if (priv->map_read_queue == NULL) {
                result = -ENOMEM;
@@ -1302,13 +1309,14 @@ int _snd_ctl_remap_open(snd_ctl_t **handlep, char *name, snd_config_t *root, snd
                SNDERR("child is not defined");
                return -EINVAL;
        }
-       if (!remap && !map) {
-               SNDERR("remap or create section is not defined");
-               return -EINVAL;
-       }
        err = _snd_ctl_open_child(&cctl, root, child, mode, conf);
        if (err < 0)
                return err;
+       /* no-op, remove the plugin */
+       if (!remap && !map) {
+               *handlep = cctl;
+               return 0;
+       }
        err = snd_ctl_remap_open(handlep, name, remap, map, cctl, mode);
        if (err < 0)
                snd_ctl_close(cctl);