From: Nick Hainke <vincent@systemli.org>
Date: Mon, 7 Dec 2020 23:07:30 +0100
Subject: [PATCH] dhcpleases: add dhcpleases plugin
Changelog: dhcpleases: add plugin for counting current dhcp leases
The plugin is useful for the Freifunk Community. Currently, we use
the exec-plugin. With that dhcpleases plugin we have native collectd
support to measure this important statistic.
Signed-off-by: Nick Hainke <vincent@systemli.org>
---
Makefile.am | 6 ++++
README | 3 ++
configure.ac | 2 ++
src/collectd.conf.in | 5 +++
src/dhcpleases.c | 83 ++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 99 insertions(+)
create mode 100644 src/dhcpleases.c
--- a/Makefile.am
+++ b/Makefile.am
@@ -963,6 +963,12 @@ df_la_LDFLAGS = $(PLUGIN_LDFLAGS)
df_la_LIBADD = libignorelist.la libmount.la
endif
+if BUILD_PLUGIN_DHCPLEASES
+pkglib_LTLIBRARIES += dhcpleases.la
+dhcpleases_la_SOURCES = src/dhcpleases.c
+dhcpleases_la_LDFLAGS = $(PLUGIN_LDFLAGS)
+endif
+
if BUILD_PLUGIN_DISK
pkglib_LTLIBRARIES += disk.la
disk_la_SOURCES = src/disk.c
--- a/README
+++ b/README
@@ -106,6 +106,9 @@ Features
Disk utilization: Sectors read/written, number of read/write actions,
average time an IO-operation took to complete.
+ - dhcpleases
+ Collect number of current dhcp leases.
+
- dns
DNS traffic: Query types, response codes, opcodes and traffic/octets
transferred.
--- a/configure.ac
+++ b/configure.ac
@@ -7063,6 +7063,7 @@ AC_PLUGIN([curl_xml], [$plugi
AC_PLUGIN([dbi], [$with_libdbi], [General database statistics])
AC_PLUGIN([dcpmm], [$with_libpmwapi], [Intel(R) Optane(TM) DC Persistent Memory performance and health statistics])
AC_PLUGIN([df], [$plugin_df], [Filesystem usage statistics])
+AC_PLUGIN([dhcpleases], [yes], [DHCP Leases])
AC_PLUGIN([disk], [$plugin_disk], [Disk usage statistics])
AC_PLUGIN([dns], [$with_libpcap], [DNS traffic analysis])
AC_PLUGIN([dpdkevents], [$plugin_dpdkevents], [Events from DPDK])
@@ -7512,6 +7513,7 @@ AC_MSG_RESULT([ curl_xml . . . . . .
AC_MSG_RESULT([ dbi . . . . . . . . . $enable_dbi])
AC_MSG_RESULT([ dcpmm . . . . . . . $enable_dcpmm])
AC_MSG_RESULT([ df . . . . . . . . . $enable_df])
+AC_MSG_RESULT([ dhcpleases. . . . . . $enable_dhcpleases])
AC_MSG_RESULT([ disk . . . . . . . . $enable_disk])
AC_MSG_RESULT([ dns . . . . . . . . . $enable_dns])
AC_MSG_RESULT([ dpdkevents. . . . . . $enable_dpdkevents])
--- a/src/collectd.conf.in
+++ b/src/collectd.conf.in
@@ -119,6 +119,7 @@
#@BUILD_PLUGIN_DBI_TRUE@LoadPlugin dbi
#@BUILD_PLUGIN_DCPMM_TRUE@LoadPlugin dcpmm
#@BUILD_PLUGIN_DF_TRUE@LoadPlugin df
+#@BUILD_PLUGIN_DHCPLEASES_TRUE@LoadPlugin dhcpleases
#@BUILD_PLUGIN_DISK_TRUE@LoadPlugin disk
#@BUILD_PLUGIN_DNS_TRUE@LoadPlugin dns
#@BUILD_PLUGIN_DPDKEVENTS_TRUE@LoadPlugin dpdkevents
@@ -690,6 +691,10 @@
# SelectNumericQueryTypes true
#</Plugin>
+#<Plugin dhcpleases>
+# Path "/tmp/dhcp.leases"
+#</Plugin>
+
#<Plugin "dpdkevents">
# <EAL>
# Coremask "0x1"
--- /dev/null
+++ b/src/dhcpleases.c
@@ -0,0 +1,83 @@
+#include <errno.h>
+#include <stdio.h>
+
+#include "utils/common/common.h"
+
+#include "configfile.h"
+#include "plugin.h"
+
+static char *dhcp_lease_file;
+
+static const char *config_keys[] = {
+ "Path",
+};
+static int config_keys_num = STATIC_ARRAY_SIZE(config_keys);
+
+/* copied from ping.c plugin */
+static int config_set_string(const char *name, /* {{{ */
+ char **var, const char *value) {
+ char *tmp;
+
+ tmp = strdup(value);
+ if (tmp == NULL) {
+ ERROR("dhcpleases plugin: Setting `%s' to `%s' failed: strdup failed: %s", name,
+ value, STRERRNO);
+ return 1;
+ }
+
+ if (*var != NULL)
+ free(*var);
+ *var = tmp;
+ return 0;
+} /* }}} int config_set_string */
+
+static int dhcpleases_config(const char *key, const char *value) {
+ if (strcasecmp(key, "Path") == 0) {
+ int status = config_set_string(key, &dhcp_lease_file, value);
+ if (status != 0)
+ return status;
+ }
+ return 0;
+}
+
+static void dhcpleases_submit(gauge_t counter) {
+ value_list_t vl = VALUE_LIST_INIT;
+ value_t values[] = {
+ {.gauge = counter},
+ };
+
+ vl.values = values;
+ vl.values_len = STATIC_ARRAY_SIZE(values);
+
+ sstrncpy(vl.plugin, "dhcpleases", sizeof(vl.plugin));
+ sstrncpy(vl.type, "count", sizeof(vl.type));
+
+ plugin_dispatch_values(&vl);
+}
+
+static int dhcp_leases_read(void) {
+
+ FILE *fh;
+ char buffer[1024];
+ gauge_t count = 0;
+
+ if ((fh = fopen(dhcp_lease_file, "r")) == NULL) {
+ WARNING("interface plugin: fopen: %s", STRERRNO);
+ return -1;
+ }
+
+ while (fgets(buffer, 1024, fh) != NULL) {
+ count++;
+ }
+ fclose(fh);
+
+ dhcpleases_submit(count);
+
+ return 0;
+}
+
+void module_register(void) {
+ plugin_register_config("dhcpleases", dhcpleases_config, config_keys,
+ config_keys_num);
+ plugin_register_read("dhcpleases", dhcp_leases_read);
+}