Merge branch 'collectd-4.7' into collectd-4.8

[collectd.git] / src / plugin.c

diff --git a/src/plugin.c b/src/plugin.c
index 24e5e01..11a0ef6 100644 (file)
--- a/src/plugin.c
+++ b/src/plugin.c
@@ -1213,8 +1213,14 @@ void plugin_shutdown_all (void)
                (*callback) ();
        }
 
-       destroy_all_callbacks (&list_write);
+       /* Write plugins which use the `user_data' pointer usually need the
+        * same data available to the flush callback. If this is the case, set
+        * the free_function to NULL when registering the flush callback and to
+        * the real free function when registering the write callback. This way
+        * the data isn't freed twice. */
        destroy_all_callbacks (&list_flush);
+       destroy_all_callbacks (&list_write);
+
        destroy_all_callbacks (&list_notification);
        destroy_all_callbacks (&list_shutdown);
        destroy_all_callbacks (&list_log);
@@ -1230,6 +1236,8 @@ int plugin_dispatch_values (value_list_t *vl)
 
        data_set_t *ds;
 
+       int free_meta_data = 0;
+
        if ((vl == NULL) || (vl->type[0] == 0)
                        || (vl->values == NULL) || (vl->values_len < 1))
        {
@@ -1237,6 +1245,12 @@ int plugin_dispatch_values (value_list_t *vl)
                return (-1);
        }
 
+       /* Free meta data only if the calling function didn't specify any. In
+        * this case matches and targets may add some and the calling function
+        * may not expect (and therefore free) that data. */
+       if (vl->meta == NULL)
+               free_meta_data = 1;
+
        if (list_write == NULL)
                c_complain_once (LOG_WARNING, &no_write_complaint,
                                "plugin_dispatch_values: No write callback has been "
@@ -1377,6 +1391,12 @@ int plugin_dispatch_values (value_list_t *vl)
                vl->values_len = saved_values_len;
        }
 
+       if ((free_meta_data != 0) && (vl->meta != NULL))
+       {
+               meta_data_destroy (vl->meta);
+               vl->meta = NULL;
+       }
+
        return (0);
 } /* int plugin_dispatch_values */