timediff match: Add a match for values with an invalid time.

The time is compared to the server's local time and values which differ
too much (configurable, of course) are matched.

diff --git a/configure.in b/configure.in
index d8cee58..6b2adc1 100644 (file)
--- a/configure.in
+++ b/configure.in
@@ -3064,6 +3064,7 @@ AC_PLUGIN([libvirt],     [$plugin_libvirt],    [Virtual machine statistics])
 AC_PLUGIN([load],        [$plugin_load],       [System load])
 AC_PLUGIN([logfile],     [yes],                [File logging plugin])
 AC_PLUGIN([match_regex], [yes],                [The regex match])
+AC_PLUGIN([match_timediff], [yes],             [The timediff match])
 AC_PLUGIN([match_value], [yes],                [The value match])
 AC_PLUGIN([mbmon],       [yes],                [Query mbmond])
 AC_PLUGIN([memcached],   [yes],                [memcached statistics])
@@ -3263,6 +3264,7 @@ Configuration:
     load  . . . . . . . . $enable_load
     logfile . . . . . . . $enable_logfile
     match_regex . . . . . $enable_match_regex
+    match_timediff  . . . $enable_match_timediff
     match_value . . . . . $enable_match_value
     mbmon . . . . . . . . $enable_mbmon
     memcached . . . . . . $enable_memcached

diff --git a/src/Makefile.am b/src/Makefile.am
index 0c3b476..5c691b2 100644 (file)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -421,6 +421,14 @@ collectd_LDADD += "-dlopen" match_regex.la
 collectd_DEPENDENCIES += match_regex.la
 endif
 
+if BUILD_PLUGIN_MATCH_TIMEDIFF
+pkglib_LTLIBRARIES += match_timediff.la
+match_timediff_la_SOURCES = match_timediff.c
+match_timediff_la_LDFLAGS = -module -avoid-version
+collectd_LDADD += "-dlopen" match_timediff.la
+collectd_DEPENDENCIES += match_timediff.la
+endif
+
 if BUILD_PLUGIN_MATCH_VALUE
 pkglib_LTLIBRARIES += match_value.la
 match_value_la_SOURCES = match_value.c

diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index 0077d24..28f86a8 100644 (file)
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -3151,6 +3151,50 @@ Example:
    Plugin "^foobar$"
  </Match>
 
+=item B<timediff>
+
+Matches values that have a time which differs from the time on the server.
+
+This match is mainly intended for servers that receive values over the
+C<network> plugin and write them to disk using the C<rrdtool> plugin. RRDtool
+is very sensitive to the timestamp used when updating the RRD files. In
+particular, the time must be ever increasing. If a misbehaving client sends one
+packet with a timestamp far in the future, all further packets with a correct
+time will be ignored because of that one packet. What's worse, such corrupted
+RRD files are hard to fix.
+
+This match lets one match all values B<outside> a specified time range
+(relative to the server's time), so you can use the B<stop> target (see below)
+to ignore the value, for example.
+
+Available options:
+
+=over 4
+
+=item B<Future> I<Seconds>
+
+Matches all values that are I<ahead> of the server's time by I<Seconds> or more
+seconds. Set to zero for no limit. Either B<Future> or B<Past> must be
+non-zero.
+
+=item B<Past> I<Seconds>
+
+Matches all values that are I<behind> of the server's time by I<Seconds> or
+more seconds. Set to zero for no limit. Either B<Future> or B<Past> must be
+non-zero.
+
+=back
+
+Example:
+
+ <Match "timediff">
+   Future  300
+   Past   3600
+ </Match>
+
+This example matches all values that are five minutes or more ahead of the
+server or one hour (or more) lagging behind.
+
 =item B<value>
 
 Matches the actual value of data sources against given minimumE<nbsp>/ maximum

diff --git a/src/match_timediff.c b/src/match_timediff.c
new file mode 100644 (file)
index 0000000..673c8d9
--- /dev/null
+++ b/src/match_timediff.c
@@ -0,0 +1,169 @@
+/**
+ * collectd - src/match_timediff.c
+ * Copyright (C) 2008,2009  Florian Forster
+ *
+ * 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
+ *
+ * Authors:
+ *   Florian Forster <octo at verplant.org>
+ **/
+
+#include "collectd.h"
+#include "common.h"
+#include "utils_cache.h"
+#include "filter_chain.h"
+
+#define SATISFY_ALL 0
+#define SATISFY_ANY 1
+
+/*
+ * private data types
+ */
+struct mt_match_s;
+typedef struct mt_match_s mt_match_t;
+struct mt_match_s
+{
+  time_t future;
+  time_t past;
+};
+
+/*
+ * internal helper functions
+ */
+static int mt_config_add_time_t (time_t *ret_value, /* {{{ */
+    oconfig_item_t *ci)
+{
+
+  if ((ci->values_num != 1) || (ci->values[0].type != OCONFIG_TYPE_NUMBER))
+  {
+    ERROR ("timediff match: `%s' needs exactly one numeric argument.",
+        ci->key);
+    return (-1);
+  }
+
+  *ret_value = (time_t) ci->values[0].value.number;
+
+  return (0);
+} /* }}} int mt_config_add_time_t */
+
+static int mt_create (const oconfig_item_t *ci, void **user_data) /* {{{ */
+{
+  mt_match_t *m;
+  int status;
+  int i;
+
+  m = (mt_match_t *) malloc (sizeof (*m));
+  if (m == NULL)
+  {
+    ERROR ("mt_create: malloc failed.");
+    return (-ENOMEM);
+  }
+  memset (m, 0, sizeof (*m));
+
+  m->future = 0;
+  m->past = 0;
+
+  status = 0;
+  for (i = 0; i < ci->children_num; i++)
+  {
+    oconfig_item_t *child = ci->children + i;
+
+    if (strcasecmp ("Future", child->key) == 0)
+      status = mt_config_add_time_t (&m->future, child);
+    else if (strcasecmp ("Past", child->key) == 0)
+      status = mt_config_add_time_t (&m->past, child);
+    else
+    {
+      ERROR ("timediff match: The `%s' configuration option is not "
+          "understood and will be ignored.", child->key);
+      status = 0;
+    }
+
+    if (status != 0)
+      break;
+  }
+
+  /* Additional sanity-checking */
+  while (status == 0)
+  {
+    if ((m->future == 0) && (m->past == 0))
+    {
+      ERROR ("timediff match: Either `Future' or `Past' must be configured. "
+          "This match will be ignored.");
+      status = -1;
+    }
+
+    break;
+  }
+
+  if (status != 0)
+  {
+    free (m);
+    return (status);
+  }
+
+  *user_data = m;
+  return (0);
+} /* }}} int mt_create */
+
+static int mt_destroy (void **user_data) /* {{{ */
+{
+  if (user_data != NULL)
+  {
+    sfree (*user_data);
+  }
+
+  return (0);
+} /* }}} int mt_destroy */
+
+static int mt_match (const data_set_t __attribute__((unused)) *ds, /* {{{ */
+    const value_list_t *vl,
+    notification_meta_t __attribute__((unused)) **meta, void **user_data)
+{
+  mt_match_t *m;
+  time_t now;
+
+  if ((user_data == NULL) || (*user_data == NULL))
+    return (-1);
+
+  m = *user_data;
+  now = time (NULL);
+
+  if (m->future != 0)
+  {
+    if (vl->time >= (now + m->future))
+      return (FC_MATCH_MATCHES);
+  }
+
+  if (m->past != 0)
+  {
+    if (vl->time <= (now - m->past))
+      return (FC_MATCH_MATCHES);
+  }
+
+  return (FC_MATCH_NO_MATCH);
+} /* }}} int mt_match */
+
+void module_register (void)
+{
+  match_proc_t mproc;
+
+  memset (&mproc, 0, sizeof (mproc));
+  mproc.create  = mt_create;
+  mproc.destroy = mt_destroy;
+  mproc.match   = mt_match;
+  fc_register_match ("value", mproc);
+} /* module_register */
+
+/* vim: set sw=2 sts=2 tw=78 et fdm=marker : */