src/plugin.c: Assure that targets get dynamically allocated memory.

[collectd.git] / src / plugin.c

diff --git a/src/plugin.c b/src/plugin.c
index 9f42f2e..367c0d1 100644 (file)
--- a/src/plugin.c
+++ b/src/plugin.c
@@ -837,9 +837,14 @@ int plugin_dispatch_values (value_list_t *vl)
        int status;
        static c_complain_t no_write_complaint = C_COMPLAIN_INIT_STATIC;
 
+       value_t *saved_values;
+       int      saved_values_len;
+
        data_set_t *ds;
 
-       if ((vl == NULL) || (*vl->type == '\0')) {
+       if ((vl == NULL) || (vl->type[0] == 0)
+                       || (vl->values == NULL) || (vl->values_len < 1))
+       {
                ERROR ("plugin_dispatch_values: Invalid value list.");
                return (-1);
        }
@@ -903,6 +908,31 @@ int plugin_dispatch_values (value_list_t *vl)
        escape_slashes (vl->type, sizeof (vl->type));
        escape_slashes (vl->type_instance, sizeof (vl->type_instance));
 
+       /* Copy the values. This way, we can assure `targets' that they get
+        * dynamically allocated values, which they can free and replace if
+        * they like. */
+       if ((pre_cache_chain != NULL) || (post_cache_chain != NULL))
+       {
+               saved_values     = vl->values;
+               saved_values_len = vl->values_len;
+
+               vl->values = (value_t *) calloc (vl->values_len,
+                               sizeof (*vl->values));
+               if (vl->values == NULL)
+               {
+                       ERROR ("plugin_dispatch_values: calloc failed.");
+                       vl->values = saved_values;
+                       return (-1);
+               }
+               memcpy (vl->values, saved_values,
+                               vl->values_len * sizeof (*vl->values));
+       }
+       else /* if ((pre == NULL) && (post == NULL)) */
+       {
+               saved_values     = NULL;
+               saved_values_len = 0;
+       }
+
        if (pre_cache_chain != NULL)
        {
                status = fc_process_chain (ds, vl, pre_cache_chain);
@@ -914,7 +944,17 @@ int plugin_dispatch_values (value_list_t *vl)
                                        status, status);
                }
                else if (status == FC_TARGET_STOP)
+               {
+                       /* Restore the state of the value_list so that plugins
+                        * don't get confused.. */
+                       if (saved_values != NULL)
+                       {
+                               free (vl->values);
+                               vl->values     = saved_values;
+                               vl->values_len = saved_values_len;
+                       }
                        return (0);
+               }
        }
 
        /* Update the value cache */
@@ -934,6 +974,15 @@ int plugin_dispatch_values (value_list_t *vl)
        else
                fc_default_action (ds, vl);
 
+       /* Restore the state of the value_list so that plugins don't get
+        * confused.. */
+       if (saved_values != NULL)
+       {
+               free (vl->values);
+               vl->values     = saved_values;
+               vl->values_len = saved_values_len;
+       }
+
        return (0);
 } /* int plugin_dispatch_values */