Filterchain: if we don't find a writer, output the available writers to syslog.

[collectd.git] / src / daemon / plugin.c

diff --git a/src/daemon/plugin.c b/src/daemon/plugin.c
index 25bd37b..b69e65b 100644 (file)
--- a/src/daemon/plugin.c
+++ b/src/daemon/plugin.c
@@ -307,6 +307,56 @@ static int register_callback (llist_t **list, /* {{{ */
        return (0);
 } /* }}} int register_callback */
 
+static void log_list_callbacks (llist_t **list, /* {{{ */
+                               const char *comment)
+{
+       char *str;
+       int len;
+       llentry_t *le;
+       int i;
+       int n;
+       char **keys;
+
+       n = llist_size(*list);
+       if (n == 0)
+       {
+               INFO("%s [none]", comment);
+               return;
+       }
+
+       keys = calloc(n, sizeof(char*));
+
+       if (keys == NULL)
+       {
+               ERROR("%s: failed to allocate memory for list of callbacks",
+                     comment);
+
+               return;
+       }
+
+       for (le = llist_head (*list), i = 0, len = 0;
+            le != NULL;
+            le = le->next, i++)
+       {
+               keys[i] = le->key;
+               len += strlen(le->key) + 6;
+       }
+       str = malloc(len + 10);
+       if (str == NULL)
+       {
+               ERROR("%s: failed to allocate memory for list of callbacks",
+                     comment);
+       }
+       else
+       {
+               *str = '\0';
+               strjoin(str, len, keys, n, "', '");
+               INFO("%s ['%s']", comment, str);
+               free(str);
+       }
+       free(keys);
+} /* }}} void log_list_callbacks */
+
 static int create_register_callback (llist_t **list, /* {{{ */
                const char *name, void *callback, user_data_t *ud)
 {
@@ -1398,6 +1448,11 @@ int plugin_unregister_read (const char *name) /* {{{ */
        return (0);
 } /* }}} int plugin_unregister_read */
 
+void plugin_log_available_writers ()
+{
+       log_list_callbacks (&list_write, "Available writers:");
+}
+
 static int compare_read_func_group (llentry_t *e, void *ud) /* {{{ */
 {
        read_func_t *rf    = e->value;