+
+int uc_get_history_by_name (const char *name,
+ gauge_t *ret_history, size_t num_steps, size_t num_ds)
+{
+ cache_entry_t *ce = NULL;
+ size_t i;
+ int status = 0;
+
+ pthread_mutex_lock (&cache_lock);
+
+ status = c_avl_get (cache_tree, name, (void *) &ce);
+ if (status != 0)
+ {
+ pthread_mutex_unlock (&cache_lock);
+ return (-ENOENT);
+ }
+
+ if (((size_t) ce->values_num) != num_ds)
+ {
+ pthread_mutex_unlock (&cache_lock);
+ return (-EINVAL);
+ }
+
+ /* Check if there are enough values available. If not, increase the buffer
+ * size. */
+ if (ce->history_length < num_steps)
+ {
+ gauge_t *tmp;
+ size_t i;
+
+ tmp = realloc (ce->history, sizeof (*ce->history)
+ * num_steps * ce->values_num);
+ if (tmp == NULL)
+ {
+ pthread_mutex_unlock (&cache_lock);
+ return (-ENOMEM);
+ }
+
+ for (i = ce->history_length * ce->values_num;
+ i < (num_steps * ce->values_num);
+ i++)
+ tmp[i] = NAN;
+
+ ce->history = tmp;
+ ce->history_length = num_steps;
+ } /* if (ce->history_length < num_steps) */
+
+ /* Copy the values to the output buffer. */
+ for (i = 0; i < num_steps; i++)
+ {
+ size_t src_index;
+ size_t dst_index;
+
+ if (i < ce->history_index)
+ src_index = ce->history_index - (i + 1);
+ else
+ src_index = ce->history_length + ce->history_index - (i + 1);
+ src_index = src_index * num_ds;
+
+ dst_index = i * num_ds;
+
+ memcpy (ret_history + dst_index, ce->history + src_index,
+ sizeof (*ret_history) * num_ds);
+ }
+
+ pthread_mutex_unlock (&cache_lock);
+
+ return (0);
+} /* int uc_get_history_by_name */
+
+int uc_get_history (const data_set_t *ds, const value_list_t *vl,
+ gauge_t *ret_history, size_t num_steps, size_t num_ds)
+{
+ char name[6 * DATA_MAX_NAME_LEN];
+
+ if (FORMAT_VL (name, sizeof (name), vl) != 0)
+ {
+ ERROR ("utils_cache: uc_get_history: FORMAT_VL failed.");
+ return (-1);
+ }
+
+ return (uc_get_history_by_name (name, ret_history, num_steps, num_ds));
+} /* int uc_get_history */
+
+int uc_get_hits (const data_set_t *ds, const value_list_t *vl)
+{
+ char name[6 * DATA_MAX_NAME_LEN];
+ cache_entry_t *ce = NULL;
+ int ret = STATE_ERROR;
+
+ if (FORMAT_VL (name, sizeof (name), vl) != 0)
+ {
+ ERROR ("uc_get_state: FORMAT_VL failed.");
+ return (STATE_ERROR);
+ }
+
+ pthread_mutex_lock (&cache_lock);
+
+ if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
+ {
+ assert (ce != NULL);
+ ret = ce->hits;
+ }
+
+ pthread_mutex_unlock (&cache_lock);
+
+ return (ret);
+} /* int uc_get_hits */
+
+int uc_set_hits (const data_set_t *ds, const value_list_t *vl, int hits)
+{
+ char name[6 * DATA_MAX_NAME_LEN];
+ cache_entry_t *ce = NULL;
+ int ret = -1;
+
+ if (FORMAT_VL (name, sizeof (name), vl) != 0)
+ {
+ ERROR ("uc_get_state: FORMAT_VL failed.");
+ return (STATE_ERROR);
+ }
+
+ pthread_mutex_lock (&cache_lock);
+
+ if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
+ {
+ assert (ce != NULL);
+ ret = ce->hits;
+ ce->hits = hits;
+ }
+
+ pthread_mutex_unlock (&cache_lock);
+
+ return (ret);
+} /* int uc_set_hits */
+
+int uc_inc_hits (const data_set_t *ds, const value_list_t *vl, int step)
+{
+ char name[6 * DATA_MAX_NAME_LEN];
+ cache_entry_t *ce = NULL;
+ int ret = -1;
+
+ if (FORMAT_VL (name, sizeof (name), vl) != 0)
+ {
+ ERROR ("uc_get_state: FORMAT_VL failed.");
+ return (STATE_ERROR);
+ }
+
+ pthread_mutex_lock (&cache_lock);
+
+ if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
+ {
+ assert (ce != NULL);
+ ret = ce->hits;
+ ce->hits = ret + step;
+ }
+
+ pthread_mutex_unlock (&cache_lock);
+
+ return (ret);
+} /* int uc_inc_hits */
+
+/*
+ * Meta data interface
+ */
+/* XXX: This function will acquire `cache_lock' but will not free it! */
+static meta_data_t *uc_get_meta (const value_list_t *vl) /* {{{ */
+{
+ char name[6 * DATA_MAX_NAME_LEN];
+ cache_entry_t *ce = NULL;
+ int status;
+
+ status = FORMAT_VL (name, sizeof (name), vl);
+ if (status != 0)
+ {
+ ERROR ("utils_cache: uc_get_meta: FORMAT_VL failed.");
+ return (NULL);
+ }
+
+ pthread_mutex_lock (&cache_lock);
+
+ status = c_avl_get (cache_tree, name, (void *) &ce);
+ if (status != 0)
+ {
+ pthread_mutex_unlock (&cache_lock);
+ return (NULL);
+ }
+ assert (ce != NULL);
+
+ if (ce->meta == NULL)
+ ce->meta = meta_data_create ();
+
+ if (ce->meta == NULL)
+ pthread_mutex_unlock (&cache_lock);
+
+ return (ce->meta);
+} /* }}} meta_data_t *uc_get_meta */
+
+/* Sorry about this preprocessor magic, but it really makes this file much
+ * shorter.. */
+#define UC_WRAP(wrap_function) { \
+ meta_data_t *meta; \
+ int status; \
+ meta = uc_get_meta (vl); \
+ if (meta == NULL) return (-1); \
+ status = wrap_function (meta, key); \
+ pthread_mutex_unlock (&cache_lock); \
+ return (status); \
+}
+int uc_meta_data_exists (const value_list_t *vl, const char *key)
+ UC_WRAP (meta_data_exists)
+
+int uc_meta_data_delete (const value_list_t *vl, const char *key)
+ UC_WRAP (meta_data_delete)
+#undef UC_WRAP
+
+/* We need a new version of this macro because the following functions take
+ * two argumetns. */
+#define UC_WRAP(wrap_function) { \
+ meta_data_t *meta; \
+ int status; \
+ meta = uc_get_meta (vl); \
+ if (meta == NULL) return (-1); \
+ status = wrap_function (meta, key, value); \
+ pthread_mutex_unlock (&cache_lock); \
+ return (status); \
+}
+int uc_meta_data_add_string (const value_list_t *vl,
+ const char *key,
+ const char *value)
+ UC_WRAP(meta_data_add_string)
+int uc_meta_data_add_signed_int (const value_list_t *vl,
+ const char *key,
+ int64_t value)
+ UC_WRAP(meta_data_add_signed_int)
+int uc_meta_data_add_unsigned_int (const value_list_t *vl,
+ const char *key,
+ uint64_t value)
+ UC_WRAP(meta_data_add_unsigned_int)
+int uc_meta_data_add_double (const value_list_t *vl,
+ const char *key,
+ double value)
+ UC_WRAP(meta_data_add_double)
+int uc_meta_data_add_boolean (const value_list_t *vl,
+ const char *key,
+ _Bool value)
+ UC_WRAP(meta_data_add_boolean)
+
+int uc_meta_data_get_string (const value_list_t *vl,
+ const char *key,
+ char **value)
+ UC_WRAP(meta_data_get_string)
+int uc_meta_data_get_signed_int (const value_list_t *vl,
+ const char *key,
+ int64_t *value)
+ UC_WRAP(meta_data_get_signed_int)
+int uc_meta_data_get_unsigned_int (const value_list_t *vl,
+ const char *key,
+ uint64_t *value)
+ UC_WRAP(meta_data_get_unsigned_int)
+int uc_meta_data_get_double (const value_list_t *vl,
+ const char *key,
+ double *value)
+ UC_WRAP(meta_data_get_double)
+int uc_meta_data_get_boolean (const value_list_t *vl,
+ const char *key,
+ _Bool *value)
+ UC_WRAP(meta_data_get_boolean)
+#undef UC_WRAP
+