Merge branch 'collectd-4.10' into collectd-5.0

diff --cc src/exec.c
Simple merge

diff --cc src/threshold.c
index 369051a2d46fff900ca778f22736c6da3139ec86,0000000000000000000000000000000000000000..277b45385d0b454e26d230203d5b1326734d4f6d
mode 100644,000000..100644
--- 1/src/threshold.c
--- /dev/null
+++ b/src/threshold.c
@@@ -1,1000 -1,0 +1,1026 @@@
-         "%f. That is %s the %s threshold of %f%s.",
 +/**
 + * collectd - src/threshold.c
 + * Copyright (C) 2007-2010  Florian Forster
 + * Copyright (C) 2008-2009  Sebastian Harl
 + * Copyright (C) 2009       Andrés J. Díaz
 + *
 + * This program is free software; you can redistribute it and/or modify it
 + * under the terms of the GNU General Public License as published by the
 + * Free Software Foundation; only version 2 of the License is applicable.
 + *
 + * This program is distributed in the hope that it will be useful, but
 + * WITHOUT ANY WARRANTY; without even the implied warranty of
 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 + * General Public License for more details.
 + *
 + * You should have received a copy of the GNU General Public License along
 + * with this program; if not, write to the Free Software Foundation, Inc.,
 + * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 + *
 + * Author:
 + *   Florian octo Forster <octo at collectd.org>
 + *   Sebastian Harl <sh at tokkee.org>
 + *   Andrés J. Díaz <ajdiaz at connectical.com>
 + **/
 +
 +#include "collectd.h"
 +#include "common.h"
 +#include "plugin.h"
 +#include "utils_avltree.h"
 +#include "utils_cache.h"
 +
 +#include <assert.h>
 +#include <pthread.h>
 +
 +/*
 + * Private data structures
 + * {{{ */
 +#define UT_FLAG_INVERT  0x01
 +#define UT_FLAG_PERSIST 0x02
 +#define UT_FLAG_PERCENTAGE 0x04
 +#define UT_FLAG_INTERESTING 0x08
 +typedef struct threshold_s
 +{
 +  char host[DATA_MAX_NAME_LEN];
 +  char plugin[DATA_MAX_NAME_LEN];
 +  char plugin_instance[DATA_MAX_NAME_LEN];
 +  char type[DATA_MAX_NAME_LEN];
 +  char type_instance[DATA_MAX_NAME_LEN];
 +  char data_source[DATA_MAX_NAME_LEN];
 +  gauge_t warning_min;
 +  gauge_t warning_max;
 +  gauge_t failure_min;
 +  gauge_t failure_max;
 +  gauge_t hysteresis;
 +  unsigned int flags;
 +  int hits;
 +  struct threshold_s *next;
 +} threshold_t;
 +/* }}} */
 +
 +/*
 + * Private (static) variables
 + * {{{ */
 +static c_avl_tree_t   *threshold_tree = NULL;
 +static pthread_mutex_t threshold_lock = PTHREAD_MUTEX_INITIALIZER;
 +/* }}} */
 +
 +/*
 + * Threshold management
 + * ====================
 + * The following functions add, delete, search, etc. configured thresholds to
 + * the underlying AVL trees.
 + */
 +/*
 + * threshold_t *threshold_get
 + *
 + * Retrieve one specific threshold configuration. For looking up a threshold
 + * matching a value_list_t, see "threshold_search" below. Returns NULL if the
 + * specified threshold doesn't exist.
 + */
 +static threshold_t *threshold_get (const char *hostname,
 +    const char *plugin, const char *plugin_instance,
 +    const char *type, const char *type_instance)
 +{ /* {{{ */
 +  char name[6 * DATA_MAX_NAME_LEN];
 +  threshold_t *th = NULL;
 +
 +  format_name (name, sizeof (name),
 +      (hostname == NULL) ? "" : hostname,
 +      (plugin == NULL) ? "" : plugin, plugin_instance,
 +      (type == NULL) ? "" : type, type_instance);
 +  name[sizeof (name) - 1] = '\0';
 +
 +  if (c_avl_get (threshold_tree, name, (void *) &th) == 0)
 +    return (th);
 +  else
 +    return (NULL);
 +} /* }}} threshold_t *threshold_get */
 +
 +/*
 + * int ut_threshold_add
 + *
 + * Adds a threshold configuration to the list of thresholds. The threshold_t
 + * structure is copied and may be destroyed after this call. Returns zero on
 + * success, non-zero otherwise.
 + */
 +static int ut_threshold_add (const threshold_t *th)
 +{ /* {{{ */
 +  char name[6 * DATA_MAX_NAME_LEN];
 +  char *name_copy;
 +  threshold_t *th_copy;
 +  threshold_t *th_ptr;
 +  int status = 0;
 +
 +  if (format_name (name, sizeof (name), th->host,
 +      th->plugin, th->plugin_instance,
 +      th->type, th->type_instance) != 0)
 +  {
 +    ERROR ("ut_threshold_add: format_name failed.");
 +    return (-1);
 +  }
 +
 +  name_copy = strdup (name);
 +  if (name_copy == NULL)
 +  {
 +    ERROR ("ut_threshold_add: strdup failed.");
 +    return (-1);
 +  }
 +
 +  th_copy = (threshold_t *) malloc (sizeof (threshold_t));
 +  if (th_copy == NULL)
 +  {
 +    sfree (name_copy);
 +    ERROR ("ut_threshold_add: malloc failed.");
 +    return (-1);
 +  }
 +  memcpy (th_copy, th, sizeof (threshold_t));
 +  th_ptr = NULL;
 +
 +  DEBUG ("ut_threshold_add: Adding entry `%s'", name);
 +
 +  pthread_mutex_lock (&threshold_lock);
 +
 +  th_ptr = threshold_get (th->host, th->plugin, th->plugin_instance,
 +      th->type, th->type_instance);
 +
 +  while ((th_ptr != NULL) && (th_ptr->next != NULL))
 +    th_ptr = th_ptr->next;
 +
 +  if (th_ptr == NULL) /* no such threshold yet */
 +  {
 +    status = c_avl_insert (threshold_tree, name_copy, th_copy);
 +  }
 +  else /* th_ptr points to the last threshold in the list */
 +  {
 +    th_ptr->next = th_copy;
 +    /* name_copy isn't needed */
 +    sfree (name_copy);
 +  }
 +
 +  pthread_mutex_unlock (&threshold_lock);
 +
 +  if (status != 0)
 +  {
 +    ERROR ("ut_threshold_add: c_avl_insert (%s) failed.", name);
 +    sfree (name_copy);
 +    sfree (th_copy);
 +  }
 +
 +  return (status);
 +} /* }}} int ut_threshold_add */
 +
 +/* 
 + * threshold_t *threshold_search
 + *
 + * Searches for a threshold configuration using all the possible variations of
 + * "Host", "Plugin" and "Type" blocks. Returns NULL if no threshold could be
 + * found.
 + * XXX: This is likely the least efficient function in collectd.
 + */
 +static threshold_t *threshold_search (const value_list_t *vl)
 +{ /* {{{ */
 +  threshold_t *th;
 +
 +  if ((th = threshold_get (vl->host, vl->plugin, vl->plugin_instance,
 +        vl->type, vl->type_instance)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get (vl->host, vl->plugin, vl->plugin_instance,
 +        vl->type, NULL)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get (vl->host, vl->plugin, NULL,
 +        vl->type, vl->type_instance)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get (vl->host, vl->plugin, NULL,
 +        vl->type, NULL)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get (vl->host, "", NULL,
 +        vl->type, vl->type_instance)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get (vl->host, "", NULL,
 +        vl->type, NULL)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get ("", vl->plugin, vl->plugin_instance,
 +        vl->type, vl->type_instance)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get ("", vl->plugin, vl->plugin_instance,
 +        vl->type, NULL)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get ("", vl->plugin, NULL,
 +        vl->type, vl->type_instance)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get ("", vl->plugin, NULL,
 +        vl->type, NULL)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get ("", "", NULL,
 +        vl->type, vl->type_instance)) != NULL)
 +    return (th);
 +  else if ((th = threshold_get ("", "", NULL,
 +        vl->type, NULL)) != NULL)
 +    return (th);
 +
 +  return (NULL);
 +} /* }}} threshold_t *threshold_search */
 +
 +/*
 + * Configuration
 + * =============
 + * The following approximately two hundred functions are used to handle the
 + * configuration and fill the threshold list.
 + * {{{ */
 +static int ut_config_type_datasource (threshold_t *th, oconfig_item_t *ci)
 +{
 +  if ((ci->values_num != 1)
 +      || (ci->values[0].type != OCONFIG_TYPE_STRING))
 +  {
 +    WARNING ("threshold values: The `DataSource' option needs exactly one "
 +      "string argument.");
 +    return (-1);
 +  }
 +
 +  sstrncpy (th->data_source, ci->values[0].value.string,
 +      sizeof (th->data_source));
 +
 +  return (0);
 +} /* int ut_config_type_datasource */
 +
 +static int ut_config_type_instance (threshold_t *th, oconfig_item_t *ci)
 +{
 +  if ((ci->values_num != 1)
 +      || (ci->values[0].type != OCONFIG_TYPE_STRING))
 +  {
 +    WARNING ("threshold values: The `Instance' option needs exactly one "
 +      "string argument.");
 +    return (-1);
 +  }
 +
 +  sstrncpy (th->type_instance, ci->values[0].value.string,
 +      sizeof (th->type_instance));
 +
 +  return (0);
 +} /* int ut_config_type_instance */
 +
 +static int ut_config_type_max (threshold_t *th, oconfig_item_t *ci)
 +{
 +  if ((ci->values_num != 1)
 +      || (ci->values[0].type != OCONFIG_TYPE_NUMBER))
 +  {
 +    WARNING ("threshold values: The `%s' option needs exactly one "
 +      "number argument.", ci->key);
 +    return (-1);
 +  }
 +
 +  if (strcasecmp (ci->key, "WarningMax") == 0)
 +    th->warning_max = ci->values[0].value.number;
 +  else
 +    th->failure_max = ci->values[0].value.number;
 +
 +  return (0);
 +} /* int ut_config_type_max */
 +
 +static int ut_config_type_min (threshold_t *th, oconfig_item_t *ci)
 +{
 +  if ((ci->values_num != 1)
 +      || (ci->values[0].type != OCONFIG_TYPE_NUMBER))
 +  {
 +    WARNING ("threshold values: The `%s' option needs exactly one "
 +      "number argument.", ci->key);
 +    return (-1);
 +  }
 +
 +  if (strcasecmp (ci->key, "WarningMin") == 0)
 +    th->warning_min = ci->values[0].value.number;
 +  else
 +    th->failure_min = ci->values[0].value.number;
 +
 +  return (0);
 +} /* int ut_config_type_min */
 +
 +static int ut_config_type_hits (threshold_t *th, oconfig_item_t *ci)
 +{
 +  if ((ci->values_num != 1)
 +      || (ci->values[0].type != OCONFIG_TYPE_NUMBER))
 +  {
 +    WARNING ("threshold values: The `%s' option needs exactly one "
 +      "number argument.", ci->key);
 +    return (-1);
 +  }
 +
 +  th->hits = ci->values[0].value.number;
 +
 +  return (0);
 +} /* int ut_config_type_hits */
 +
 +static int ut_config_type_hysteresis (threshold_t *th, oconfig_item_t *ci)
 +{
 +  if ((ci->values_num != 1)
 +      || (ci->values[0].type != OCONFIG_TYPE_NUMBER))
 +  {
 +    WARNING ("threshold values: The `%s' option needs exactly one "
 +      "number argument.", ci->key);
 +    return (-1);
 +  }
 +
 +  th->hysteresis = ci->values[0].value.number;
 +
 +  return (0);
 +} /* int ut_config_type_hysteresis */
 +
 +static int ut_config_type (const threshold_t *th_orig, oconfig_item_t *ci)
 +{
 +  int i;
 +  threshold_t th;
 +  int status = 0;
 +
 +  if ((ci->values_num != 1)
 +      || (ci->values[0].type != OCONFIG_TYPE_STRING))
 +  {
 +    WARNING ("threshold values: The `Type' block needs exactly one string "
 +      "argument.");
 +    return (-1);
 +  }
 +
 +  if (ci->children_num < 1)
 +  {
 +    WARNING ("threshold values: The `Type' block needs at least one option.");
 +    return (-1);
 +  }
 +
 +  memcpy (&th, th_orig, sizeof (th));
 +  sstrncpy (th.type, ci->values[0].value.string, sizeof (th.type));
 +
 +  th.warning_min = NAN;
 +  th.warning_max = NAN;
 +  th.failure_min = NAN;
 +  th.failure_max = NAN;
 +  th.hits = 0;
 +  th.hysteresis = 0;
 +  th.flags = UT_FLAG_INTERESTING; /* interesting by default */
 +
 +  for (i = 0; i < ci->children_num; i++)
 +  {
 +    oconfig_item_t *option = ci->children + i;
 +    status = 0;
 +
 +    if (strcasecmp ("Instance", option->key) == 0)
 +      status = ut_config_type_instance (&th, option);
 +    else if (strcasecmp ("DataSource", option->key) == 0)
 +      status = ut_config_type_datasource (&th, option);
 +    else if ((strcasecmp ("WarningMax", option->key) == 0)
 +      || (strcasecmp ("FailureMax", option->key) == 0))
 +      status = ut_config_type_max (&th, option);
 +    else if ((strcasecmp ("WarningMin", option->key) == 0)
 +      || (strcasecmp ("FailureMin", option->key) == 0))
 +      status = ut_config_type_min (&th, option);
 +    else if (strcasecmp ("Interesting", option->key) == 0)
 +      status = cf_util_get_flag (option, &th.flags, UT_FLAG_INTERESTING);
 +    else if (strcasecmp ("Invert", option->key) == 0)
 +      status = cf_util_get_flag (option, &th.flags, UT_FLAG_INVERT);
 +    else if (strcasecmp ("Persist", option->key) == 0)
 +      status = cf_util_get_flag (option, &th.flags, UT_FLAG_PERSIST);
 +    else if (strcasecmp ("Percentage", option->key) == 0)
 +      status = cf_util_get_flag (option, &th.flags, UT_FLAG_PERCENTAGE);
 +    else if (strcasecmp ("Hits", option->key) == 0)
 +      status = ut_config_type_hits (&th, option);
 +    else if (strcasecmp ("Hysteresis", option->key) == 0)
 +      status = ut_config_type_hysteresis (&th, option);
 +    else
 +    {
 +      WARNING ("threshold values: Option `%s' not allowed inside a `Type' "
 +        "block.", option->key);
 +      status = -1;
 +    }
 +
 +    if (status != 0)
 +      break;
 +  }
 +
 +  if (status == 0)
 +  {
 +    status = ut_threshold_add (&th);
 +  }
 +
 +  return (status);
 +} /* int ut_config_type */
 +
 +static int ut_config_plugin_instance (threshold_t *th, oconfig_item_t *ci)
 +{
 +  if ((ci->values_num != 1)
 +      || (ci->values[0].type != OCONFIG_TYPE_STRING))
 +  {
 +    WARNING ("threshold values: The `Instance' option needs exactly one "
 +      "string argument.");
 +    return (-1);
 +  }
 +
 +  sstrncpy (th->plugin_instance, ci->values[0].value.string,
 +      sizeof (th->plugin_instance));
 +
 +  return (0);
 +} /* int ut_config_plugin_instance */
 +
 +static int ut_config_plugin (const threshold_t *th_orig, oconfig_item_t *ci)
 +{
 +  int i;
 +  threshold_t th;
 +  int status = 0;
 +
 +  if ((ci->values_num != 1)
 +      || (ci->values[0].type != OCONFIG_TYPE_STRING))
 +  {
 +    WARNING ("threshold values: The `Plugin' block needs exactly one string "
 +      "argument.");
 +    return (-1);
 +  }
 +
 +  if (ci->children_num < 1)
 +  {
 +    WARNING ("threshold values: The `Plugin' block needs at least one nested "
 +      "block.");
 +    return (-1);
 +  }
 +
 +  memcpy (&th, th_orig, sizeof (th));
 +  sstrncpy (th.plugin, ci->values[0].value.string, sizeof (th.plugin));
 +
 +  for (i = 0; i < ci->children_num; i++)
 +  {
 +    oconfig_item_t *option = ci->children + i;
 +    status = 0;
 +
 +    if (strcasecmp ("Type", option->key) == 0)
 +      status = ut_config_type (&th, option);
 +    else if (strcasecmp ("Instance", option->key) == 0)
 +      status = ut_config_plugin_instance (&th, option);
 +    else
 +    {
 +      WARNING ("threshold values: Option `%s' not allowed inside a `Plugin' "
 +        "block.", option->key);
 +      status = -1;
 +    }
 +
 +    if (status != 0)
 +      break;
 +  }
 +
 +  return (status);
 +} /* int ut_config_plugin */
 +
 +static int ut_config_host (const threshold_t *th_orig, oconfig_item_t *ci)
 +{
 +  int i;
 +  threshold_t th;
 +  int status = 0;
 +
 +  if ((ci->values_num != 1)
 +      || (ci->values[0].type != OCONFIG_TYPE_STRING))
 +  {
 +    WARNING ("threshold values: The `Host' block needs exactly one string "
 +      "argument.");
 +    return (-1);
 +  }
 +
 +  if (ci->children_num < 1)
 +  {
 +    WARNING ("threshold values: The `Host' block needs at least one nested "
 +      "block.");
 +    return (-1);
 +  }
 +
 +  memcpy (&th, th_orig, sizeof (th));
 +  sstrncpy (th.host, ci->values[0].value.string, sizeof (th.host));
 +
 +  for (i = 0; i < ci->children_num; i++)
 +  {
 +    oconfig_item_t *option = ci->children + i;
 +    status = 0;
 +
 +    if (strcasecmp ("Type", option->key) == 0)
 +      status = ut_config_type (&th, option);
 +    else if (strcasecmp ("Plugin", option->key) == 0)
 +      status = ut_config_plugin (&th, option);
 +    else
 +    {
 +      WARNING ("threshold values: Option `%s' not allowed inside a `Host' "
 +        "block.", option->key);
 +      status = -1;
 +    }
 +
 +    if (status != 0)
 +      break;
 +  }
 +
 +  return (status);
 +} /* int ut_config_host */
 +
 +int ut_config (oconfig_item_t *ci)
 +{
 +  int i;
 +  int status = 0;
 +
 +  threshold_t th;
 +
 +  if (ci->values_num != 0)
 +  {
 +    ERROR ("threshold values: The `Threshold' block may not have any "
 +      "arguments.");
 +    return (-1);
 +  }
 +
 +  if (threshold_tree == NULL)
 +  {
 +    threshold_tree = c_avl_create ((void *) strcmp);
 +    if (threshold_tree == NULL)
 +    {
 +      ERROR ("ut_config: c_avl_create failed.");
 +      return (-1);
 +    }
 +  }
 +
 +  memset (&th, '\0', sizeof (th));
 +  th.warning_min = NAN;
 +  th.warning_max = NAN;
 +  th.failure_min = NAN;
 +  th.failure_max = NAN;
 +
 +  th.hits = 0;
 +  th.hysteresis = 0;
 +  th.flags = UT_FLAG_INTERESTING; /* interesting by default */
 +    
 +  for (i = 0; i < ci->children_num; i++)
 +  {
 +    oconfig_item_t *option = ci->children + i;
 +    status = 0;
 +
 +    if (strcasecmp ("Type", option->key) == 0)
 +      status = ut_config_type (&th, option);
 +    else if (strcasecmp ("Plugin", option->key) == 0)
 +      status = ut_config_plugin (&th, option);
 +    else if (strcasecmp ("Host", option->key) == 0)
 +      status = ut_config_host (&th, option);
 +    else
 +    {
 +      WARNING ("threshold values: Option `%s' not allowed here.", option->key);
 +      status = -1;
 +    }
 +
 +    if (status != 0)
 +      break;
 +  }
 +
 +  return (status);
 +} /* int um_config */
 +/*
 + * End of the functions used to configure threshold values.
 + */
 +/* }}} */
 +
 +/*
 + * int ut_report_state
 + *
 + * Checks if the `state' differs from the old state and creates a notification
 + * if appropriate.
 + * Does not fail.
 + */
 +static int ut_report_state (const data_set_t *ds,
 +    const value_list_t *vl,
 +    const threshold_t *th,
 +    const gauge_t *values,
 +    int ds_index,
 +    int state)
 +{ /* {{{ */
 +  int state_old;
 +  notification_t n;
 +
 +  char *buf;
 +  size_t bufsize;
 +
 +  int status;
 +
 +  /* Check if hits matched */
 +  if ( (th->hits != 0) )
 +  {
 +    int hits = uc_get_hits(ds,vl);
 +    /* The STATE_OKAY always reset hits, or if hits reaise the limit */
 +    if ( (state == STATE_OKAY) || (hits > th->hits) )
 +    {
 +        DEBUG("ut_report_state: reset uc_get_hits = 0");
 +        uc_set_hits(ds,vl,0); /* reset hit counter and notify */
 +    } else {
 +      DEBUG("ut_report_state: th->hits = %d, uc_get_hits = %d",th->hits,uc_get_hits(ds,vl));
 +      (void) uc_inc_hits(ds,vl,1); /* increase hit counter */
 +      return (0);
 +    }
 +  } /* end check hits */
 +
 +  state_old = uc_get_state (ds, vl);
 +
 +  /* If the state didn't change, only report if `persistent' is specified and
 +   * the state is not `okay'. */
 +  if (state == state_old)
 +  {
 +    if ((th->flags & UT_FLAG_PERSIST) == 0)
 +      return (0);
 +    else if (state == STATE_OKAY)
 +      return (0);
 +  }
 +
 +  if (state != state_old)
 +    uc_set_state (ds, vl, state);
 +
 +  NOTIFICATION_INIT_VL (&n, vl);
 +
 +  buf = n.message;
 +  bufsize = sizeof (n.message);
 +
 +  if (state == STATE_OKAY)
 +    n.severity = NOTIF_OKAY;
 +  else if (state == STATE_WARNING)
 +    n.severity = NOTIF_WARNING;
 +  else
 +    n.severity = NOTIF_FAILURE;
 +
 +  n.time = vl->time;
 +
 +  status = ssnprintf (buf, bufsize, "Host %s, plugin %s",
 +      vl->host, vl->plugin);
 +  buf += status;
 +  bufsize -= status;
 +
 +  if (vl->plugin_instance[0] != '\0')
 +  {
 +    status = ssnprintf (buf, bufsize, " (instance %s)",
 +      vl->plugin_instance);
 +    buf += status;
 +    bufsize -= status;
 +  }
 +
 +  status = ssnprintf (buf, bufsize, " type %s", vl->type);
 +  buf += status;
 +  bufsize -= status;
 +
 +  if (vl->type_instance[0] != '\0')
 +  {
 +    status = ssnprintf (buf, bufsize, " (instance %s)",
 +      vl->type_instance);
 +    buf += status;
 +    bufsize -= status;
 +  }
 +
 +  plugin_notification_meta_add_string (&n, "DataSource",
 +      ds->ds[ds_index].name);
 +  plugin_notification_meta_add_double (&n, "CurrentValue", values[ds_index]);
 +  plugin_notification_meta_add_double (&n, "WarningMin", th->warning_min);
 +  plugin_notification_meta_add_double (&n, "WarningMax", th->warning_max);
 +  plugin_notification_meta_add_double (&n, "FailureMin", th->failure_min);
 +  plugin_notification_meta_add_double (&n, "FailureMax", th->failure_max);
 +
 +  /* Send an okay notification */
 +  if (state == STATE_OKAY)
 +  {
 +    if (state_old == STATE_MISSING)
 +      status = ssnprintf (buf, bufsize,
 +          ": Value is no longer missing.");
 +    else
 +      status = ssnprintf (buf, bufsize,
 +          ": All data sources are within range again.");
 +    buf += status;
 +    bufsize -= status;
 +  }
 +  else
 +  {
 +    double min;
 +    double max;
 +
 +    min = (state == STATE_ERROR) ? th->failure_min : th->warning_min;
 +    max = (state == STATE_ERROR) ? th->failure_max : th->warning_max;
 +
 +    if (th->flags & UT_FLAG_INVERT)
 +    {
 +      if (!isnan (min) && !isnan (max))
 +      {
 +        status = ssnprintf (buf, bufsize, ": Data source \"%s\" is currently "
 +            "%f. That is within the %s region of %f%s and %f%s.",
 +            ds->ds[ds_index].name, values[ds_index],
 +            (state == STATE_ERROR) ? "failure" : "warning",
 +            min, ((th->flags & UT_FLAG_PERCENTAGE) != 0) ? "%" : "",
 +            max, ((th->flags & UT_FLAG_PERCENTAGE) != 0) ? "%" : "");
 +      }
 +      else
 +      {
 +      status = ssnprintf (buf, bufsize, ": Data source \"%s\" is currently "
 +          "%f. That is %s the %s threshold of %f%s.",
 +          ds->ds[ds_index].name, values[ds_index],
 +          isnan (min) ? "below" : "above",
 +          (state == STATE_ERROR) ? "failure" : "warning",
 +          isnan (min) ? max : min,
 +          ((th->flags & UT_FLAG_PERCENTAGE) != 0) ? "%" : "");
 +      }
 +    }
++    else if (th->flags & UT_FLAG_PERCENTAGE)
++    {
++      gauge_t value;
++      gauge_t sum;
++      int i;
++
++      sum = 0.0;
++      for (i = 0; i < vl->values_len; i++)
++      {
++        if (isnan (values[i]))
++          continue;
++
++        sum += values[i];
++      }
++
++      if (sum == 0.0)
++        value = NAN;
++      else
++        value = 100.0 * values[ds_index] / sum;
++
++      status = ssnprintf (buf, bufsize, ": Data source \"%s\" is currently "
++          "%g (%.2f%%). That is %s the %s threshold of %.2f%%.",
++          ds->ds[ds_index].name, values[ds_index], value,
++          (value < min) ? "below" : "above",
++          (state == STATE_ERROR) ? "failure" : "warning",
++          (value < min) ? min : max);
++    }
 +    else /* is not inverted */
 +    {
 +      status = ssnprintf (buf, bufsize, ": Data source \"%s\" is currently "
-         (values[ds_index] < min) ? min : max,
-         ((th->flags & UT_FLAG_PERCENTAGE) != 0) ? "%" : "");
++        "%f. That is %s the %s threshold of %f.",
 +        ds->ds[ds_index].name, values[ds_index],
 +        (values[ds_index] < min) ? "below" : "above",
 +        (state == STATE_ERROR) ? "failure" : "warning",
++        (values[ds_index] < min) ? min : max);
 +    }
 +    buf += status;
 +    bufsize -= status;
 +  }
 +
 +  plugin_dispatch_notification (&n);
 +
 +  plugin_notification_meta_free (n.meta);
 +  return (0);
 +} /* }}} int ut_report_state */
 +
 +/*
 + * int ut_check_one_data_source
 + *
 + * Checks one data source against the given threshold configuration. If the
 + * `DataSource' option is set in the threshold, and the name does NOT match,
 + * `okay' is returned. If the threshold does match, its failure and warning
 + * min and max values are checked and `failure' or `warning' is returned if
 + * appropriate.
 + * Does not fail.
 + */
 +static int ut_check_one_data_source (const data_set_t *ds,
 +    const value_list_t __attribute__((unused)) *vl,
 +    const threshold_t *th,
 +    const gauge_t *values,
 +    int ds_index)
 +{ /* {{{ */
 +  const char *ds_name;
 +  int is_warning = 0;
 +  int is_failure = 0;
 +  int prev_state = STATE_OKAY;
 +
 +  /* check if this threshold applies to this data source */
 +  if (ds != NULL)
 +  {
 +    ds_name = ds->ds[ds_index].name;
 +    if ((th->data_source[0] != 0)
 +      && (strcmp (ds_name, th->data_source) != 0))
 +      return (STATE_OKAY);
 +  }
 +
 +  if ((th->flags & UT_FLAG_INVERT) != 0)
 +  {
 +    is_warning--;
 +    is_failure--;
 +  }
 +
 +  /* XXX: This is an experimental code, not optimized, not fast, not reliable,
 +   * and probably, do not work as you expect. Enjoy! :D */
 +  if ( (th->hysteresis > 0) && ((prev_state = uc_get_state(ds,vl)) != STATE_OKAY) )
 +  {
 +    switch(prev_state)
 +    {
 +      case STATE_ERROR:
 +      if ( (!isnan (th->failure_min) && ((th->failure_min + th->hysteresis) < values[ds_index])) ||
 +           (!isnan (th->failure_max) && ((th->failure_max - th->hysteresis) > values[ds_index])) )
 +        return (STATE_OKAY);
 +      else
 +        is_failure++;
 +      case STATE_WARNING:
 +      if ( (!isnan (th->warning_min) && ((th->warning_min + th->hysteresis) < values[ds_index])) ||
 +           (!isnan (th->warning_max) && ((th->warning_max - th->hysteresis) > values[ds_index])) )
 +        return (STATE_OKAY);
 +      else
 +        is_warning++;
 +     }
 +  }
 +  else { /* no hysteresis */
 +    if ((!isnan (th->failure_min) && (th->failure_min > values[ds_index]))
 +      || (!isnan (th->failure_max) && (th->failure_max < values[ds_index])))
 +      is_failure++;
 +
 +    if ((!isnan (th->warning_min) && (th->warning_min > values[ds_index]))
 +      || (!isnan (th->warning_max) && (th->warning_max < values[ds_index])))
 +      is_warning++;
 + }
 +
 +  if (is_failure != 0)
 +    return (STATE_ERROR);
 +
 +  if (is_warning != 0)
 +    return (STATE_WARNING);
 +
 +  return (STATE_OKAY);
 +} /* }}} int ut_check_one_data_source */
 +
 +/*
 + * int ut_check_one_threshold
 + *
 + * Checks all data sources of a value list against the given threshold, using
 + * the ut_check_one_data_source function above. Returns the worst status,
 + * which is `okay' if nothing has failed.
 + * Returns less than zero if the data set doesn't have any data sources.
 + */
 +static int ut_check_one_threshold (const data_set_t *ds,
 +    const value_list_t *vl,
 +    const threshold_t *th,
 +    const gauge_t *values,
 +    int *ret_ds_index)
 +{ /* {{{ */
 +  int ret = -1;
 +  int ds_index = -1;
 +  int i;
 +  gauge_t values_copy[ds->ds_num];
 +
 +  memcpy (values_copy, values, sizeof (values_copy));
 +
 +  if ((th->flags & UT_FLAG_PERCENTAGE) != 0)
 +  {
 +    int num = 0;
 +    gauge_t sum=0.0;
 +
 +    if (ds->ds_num == 1)
 +    {
 +      WARNING ("ut_check_one_threshold: The %s type has only one data "
 +          "source, but you have configured to check this as a percentage. "
 +          "That doesn't make much sense, because the percentage will always "
 +          "be 100%%!", ds->type);
 +    }
 +
 +    /* Prepare `sum' and `num'. */
 +    for (i = 0; i < ds->ds_num; i++)
 +      if (!isnan (values[i]))
 +      {
 +        num++;
 +      sum += values[i];
 +      }
 +
 +    if ((num == 0) /* All data sources are undefined. */
 +        || (sum == 0.0)) /* Sum is zero, cannot calculate percentage. */
 +    {
 +      for (i = 0; i < ds->ds_num; i++)
 +        values_copy[i] = NAN;
 +    }
 +    else /* We can actually calculate the percentage. */
 +    {
 +      for (i = 0; i < ds->ds_num; i++)
 +        values_copy[i] = 100.0 * values[i] / sum;
 +    }
 +  } /* if (UT_FLAG_PERCENTAGE) */
 +
 +  for (i = 0; i < ds->ds_num; i++)
 +  {
 +    int status;
 +
 +    status = ut_check_one_data_source (ds, vl, th, values_copy, i);
 +    if (ret < status)
 +    {
 +      ret = status;
 +      ds_index = i;
 +    }
 +  } /* for (ds->ds_num) */
 +
 +  if (ret_ds_index != NULL)
 +    *ret_ds_index = ds_index;
 +
 +  return (ret);
 +} /* }}} int ut_check_one_threshold */
 +
 +/*
 + * int ut_check_threshold
 + *
 + * Gets a list of matching thresholds and searches for the worst status by one
 + * of the thresholds. Then reports that status using the ut_report_state
 + * function above. 
 + * Returns zero on success and if no threshold has been configured. Returns
 + * less than zero on failure.
 + */
 +static int ut_check_threshold (const data_set_t *ds, const value_list_t *vl,
 +    __attribute__((unused)) user_data_t *ud)
 +{ /* {{{ */
 +  threshold_t *th;
 +  gauge_t *values;
 +  int status;
 +
 +  int worst_state = -1;
 +  threshold_t *worst_th = NULL;
 +  int worst_ds_index = -1;
 +
 +  if (threshold_tree == NULL)
 +    return (0);
 +
 +  /* Is this lock really necessary? So far, thresholds are only inserted at
 +   * startup. -octo */
 +  pthread_mutex_lock (&threshold_lock);
 +  th = threshold_search (vl);
 +  pthread_mutex_unlock (&threshold_lock);
 +  if (th == NULL)
 +    return (0);
 +
 +  DEBUG ("ut_check_threshold: Found matching threshold(s)");
 +
 +  values = uc_get_rate (ds, vl);
 +  if (values == NULL)
 +    return (0);
 +
 +  while (th != NULL)
 +  {
 +    int ds_index = -1;
 +
 +    status = ut_check_one_threshold (ds, vl, th, values, &ds_index);
 +    if (status < 0)
 +    {
 +      ERROR ("ut_check_threshold: ut_check_one_threshold failed.");
 +      sfree (values);
 +      return (-1);
 +    }
 +
 +    if (worst_state < status)
 +    {
 +      worst_state = status;
 +      worst_th = th;
 +      worst_ds_index = ds_index;
 +    }
 +
 +    th = th->next;
 +  } /* while (th) */
 +
 +  status = ut_report_state (ds, vl, worst_th, values,
 +      worst_ds_index, worst_state);
 +  if (status != 0)
 +  {
 +    ERROR ("ut_check_threshold: ut_report_state failed.");
 +    sfree (values);
 +    return (-1);
 +  }
 +
 +  sfree (values);
 +
 +  return (0);
 +} /* }}} int ut_check_threshold */
 +
 +/*
 + * int ut_missing
 + *
 + * This function is called whenever a value goes "missing".
 + */
 +static int ut_missing (const value_list_t *vl,
 +    __attribute__((unused)) user_data_t *ud)
 +{ /* {{{ */
 +  threshold_t *th;
 +  cdtime_t missing_time;
 +  char identifier[6 * DATA_MAX_NAME_LEN];
 +  notification_t n;
 +
 +  th = threshold_search (vl);
 +  if (th == NULL)
 +    return (0);
 +
 +  missing_time = cdtime () - vl->time;
 +  FORMAT_VL (identifier, sizeof (identifier), vl);
 +
 +  NOTIFICATION_INIT_VL (&n, vl);
 +  ssnprintf (n.message, sizeof (n.message),
 +      "%s has not been updated for %.3f seconds.",
 +      identifier, CDTIME_T_TO_DOUBLE (missing_time));
 +
 +  plugin_dispatch_notification (&n);
 +
 +  return (0);
 +} /* }}} int ut_missing */
 +
 +void module_register (void)
 +{
 +  plugin_register_complex_config ("threshold", ut_config);
 +  plugin_register_missing ("threshold", ut_missing,
 +      /* user data = */ NULL);
 +  plugin_register_write ("threshold", ut_check_threshold,
 +      /* user data = */ NULL);
 +}
 +
 +/* vim: set sw=2 ts=8 sts=2 tw=78 et fdm=marker : */