Merge remote-tracking branch 'github/pr/387'

[collectd.git] / src / utils_cache.c

diff --git a/src/utils_cache.c b/src/utils_cache.c
index dd5bcb59ffc9833b2a92341a085e32d526e9e812..fa6e6603ec3e10eedcdc6ea7d56ab64a0b04db6e 100644 (file)
--- a/src/utils_cache.c
+++ b/src/utils_cache.c
@@ -572,6 +572,7 @@ int uc_get_names (char ***ret_names, cdtime_t **ret_times, size_t *ret_number)
   char **names = NULL;
   cdtime_t *times = NULL;
   size_t number = 0;
+  size_t size_arrays = 0;
 
   int status = 0;
 
@@ -580,42 +581,47 @@ int uc_get_names (char ***ret_names, cdtime_t **ret_times, size_t *ret_number)
 
   pthread_mutex_lock (&cache_lock);
 
+  size_arrays = (size_t) c_avl_size (cache_tree);
+  if (size_arrays < 1)
+  {
+    /* Handle the "no values" case here, to avoid the error message when
+     * calloc() returns NULL. */
+    pthread_mutex_unlock (&cache_lock);
+    return (0);
+  }
+
+  names = calloc (size_arrays, sizeof (*names));
+  times = calloc (size_arrays, sizeof (*times));
+  if ((names == NULL) || (times == NULL))
+  {
+    ERROR ("uc_get_names: calloc failed.");
+    sfree (names);
+    sfree (times);
+    pthread_mutex_unlock (&cache_lock);
+    return (ENOMEM);
+  }
+
   iter = c_avl_get_iterator (cache_tree);
   while (c_avl_iterator_next (iter, (void *) &key, (void *) &value) == 0)
   {
-    char **temp;
-
     /* remove missing values when list values */
     if (value->state == STATE_MISSING)
       continue;
 
-    if (ret_times != NULL)
-    {
-      cdtime_t *tmp_times;
+    /* c_avl_size does not return a number smaller than the number of elements
+     * returned by c_avl_iterator_next. */
+    assert (number < size_arrays);
 
-      tmp_times = (cdtime_t *) realloc (times, sizeof (cdtime_t) * (number + 1));
-      if (tmp_times == NULL)
-      {
-       status = -1;
-       break;
-      }
-      times = tmp_times;
+    if (ret_times != NULL)
       times[number] = value->last_time;
-    }
 
-    temp = (char **) realloc (names, sizeof (char *) * (number + 1));
-    if (temp == NULL)
-    {
-      status = -1;
-      break;
-    }
-    names = temp;
     names[number] = strdup (key);
     if (names[number] == NULL)
     {
       status = -1;
       break;
     }
+
     number++;
   } /* while (c_avl_iterator_next) */