rrdtool plugin: Correctly free the cache when shutting down.

diff --git a/src/rrdtool.c b/src/rrdtool.c
index ed1ced1..01fca30 100644 (file)
--- a/src/rrdtool.c
+++ b/src/rrdtool.c
@@ -432,11 +432,6 @@ static void *rrd_queue_thread (void __attribute__((unused)) *data)
                sfree (queue_entry);
        } /* while (42) */
 
-       pthread_mutex_lock (&cache_lock);
-       c_avl_destroy (cache);
-       cache = NULL;
-       pthread_mutex_unlock (&cache_lock);
-
        pthread_exit ((void *) 0);
        return ((void *) 0);
 } /* void *rrd_queue_thread */
@@ -786,6 +781,59 @@ static int rrd_cache_insert (const char *filename,
        return (0);
 } /* int rrd_cache_insert */
 
+static int rrd_cache_destroy (void) /* {{{ */
+{
+  void *key = NULL;
+  void *value = NULL;
+
+  int non_empty = 0;
+
+  pthread_mutex_lock (&cache_lock);
+
+  if (cache == NULL)
+  {
+    pthread_mutex_unlock (&cache_lock);
+    return (0);
+  }
+
+  while (c_avl_pick (cache, &key, &value) == 0)
+  {
+    rrd_cache_t *rc;
+    int i;
+
+    sfree (key);
+    key = NULL;
+
+    rc = value;
+    value = NULL;
+
+    if (rc->values_num > 0)
+      non_empty++;
+
+    for (i = 0; i < rc->values_num; i++)
+      sfree (rc->values[i]);
+    sfree (rc->values);
+    sfree (rc);
+  }
+
+  c_avl_destroy (cache);
+  cache = NULL;
+
+  if (non_empty > 0)
+  {
+    INFO ("rrdtool plugin: %i cache %s had values when destroying the cache.",
+        non_empty, (non_empty == 1) ? "entry" : "entries");
+  }
+  else
+  {
+    DEBUG ("rrdtool plugin: No values have been lost "
+        "when destroying the cache.");
+  }
+
+  pthread_mutex_unlock (&cache_lock);
+  return (0);
+} /* }}} int rrd_cache_destroy */
+
 static int rrd_compare_numeric (const void *a_ptr, const void *b_ptr)
 {
        int a = *((int *) a_ptr);
@@ -807,6 +855,9 @@ static int rrd_write (const data_set_t *ds, const value_list_t *vl,
        char         values[512];
        int          status;
 
+       if (do_shutdown)
+               return (0);
+
        if (0 != strcmp (ds->type, vl->type)) {
                ERROR ("rrdtool plugin: DS type does not match value list type");
                return -1;
@@ -1063,7 +1114,7 @@ static int rrd_shutdown (void)
                DEBUG ("rrdtool plugin: queue_thread exited.");
        }
 
-       /* TODO: Maybe it'd be a good idea to free the cache here.. */
+       rrd_cache_destroy ();
 
        return (0);
 } /* int rrd_shutdown */