From 1cc2a8257dfebcdd899928145d9cd6997086ed19 Mon Sep 17 00:00:00 2001
From: Florian Forster <sifnfors@faui02h.informatik.uni-erlangen.de>
Date: Mon, 22 Jan 2007 09:59:47 +0100
Subject: [PATCH] entropy plugin: Added a plugin to collect available entropy.

Only works on Linux systems right now..
---
 configure.in    |  2 ++
 src/Makefile.am |  8 +++++
 src/entropy.c   | 97 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 107 insertions(+)
 create mode 100644 src/entropy.c

diff --git a/configure.in b/configure.in
index ac6e5c99..0b0aa890 100644
--- a/configure.in
+++ b/configure.in
@@ -988,6 +988,7 @@ AC_COLLECTD([csv],       [disable], [module], [csv output plugin])
 AC_COLLECTD([df],        [disable], [module], [df statistics])
 AC_COLLECTD([dns],       [disable], [module], [dns statistics])
 AC_COLLECTD([email],     [disable], [module], [email statistics])
+AC_COLLECTD([entropy],   [disable], [module], [entropy statistics])
 AC_COLLECTD([hddtemp],   [disable], [module], [hdd temperature statistics])
 AC_COLLECTD([load],      [disable], [module], [system load statistics])
 AC_COLLECTD([mbmon],     [disable], [module], [motherboard monitor statistics])
@@ -1043,6 +1044,7 @@ Configuration:
     disk  . . . . . . . $enable_disk
     dns . . . . . . . . $enable_dns
     email . . . . . . . $enable_email
+    entropy . . . . . . $enable_entropy
     hddtemp . . . . . . $enable_hddtemp
     load  . . . . . . . $enable_load
     mbmon . . . . . . . $enable_mbmon
diff --git a/src/Makefile.am b/src/Makefile.am
index 55584191..87dcec07 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -186,6 +186,14 @@ collectd_LDADD += "-dlopen" email.la
 collectd_DEPENDENCIES += email.la
 endif
 
+if BUILD_MODULE_ENTROPY
+pkglib_LTLIBRARIES += entropy.la
+entropy_la_SOURCES = entropy.c
+entropy_la_LDFLAGS = -module -avoid-version
+collectd_LDADD += "-dlopen" entropy.la
+collectd_DEPENDENCIES += entropy.la
+endif
+
 #if BUILD_MODULE_QUOTA
 #pkglib_LTLIBRARIES += quota.la
 #quota_la_SOURCES = quota_plugin.c quota_plugin.h
diff --git a/src/entropy.c b/src/entropy.c
new file mode 100644
index 00000000..7e0a8174
--- /dev/null
+++ b/src/entropy.c
@@ -0,0 +1,97 @@
+/**
+ * collectd - src/entropy.c
+ * Copyright (C) 2005,2006  Florian octo 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 octo Forster <octo at verplant.org>
+ **/
+
+#include "collectd.h"
+#include "common.h"
+#include "plugin.h"
+
+#if KERNEL_LINUX
+# define ENTROPY_HAVE_READ 1
+#else
+# define ENTROPY_HAVE_READ 0
+#endif
+
+#define ENTROPY_FILE "/proc/sys/kernel/random/entropy_avail"
+
+static data_source_t dsrc[1] =
+{
+	{"entropy",  DS_TYPE_GAUGE, 0.0, 4294967295.0}
+};
+
+static data_set_t ds =
+{
+	"entropy", 1, dsrc
+};
+
+#if ENTROPY_HAVE_READ
+static void entropy_submit (double entropy)
+{
+	value_t values[1];
+	value_list_t vl = VALUE_LIST_INIT;
+
+	values[0].gauge = entropy;
+
+	vl.values = values;
+	vl.values_len = 1;
+	vl.time = time (NULL);
+	strcpy (vl.host, hostname);
+	strcpy (vl.plugin, "entropy");
+	strcpy (vl.plugin_instance, "");
+	strcpy (vl.type_instance, "");
+
+	plugin_dispatch_values ("entropy", &vl);
+}
+
+static int entropy_read (void)
+{
+#if KERNEL_LINUX
+	double entropy;
+	FILE *fh;
+	char buffer[64];
+
+	fh = fopen (ENTROPY_FILE, "r");
+	if (fh == NULL)
+		return (-1);
+
+	if (fgets (buffer, sizeof (buffer), fh) == NULL)
+	{
+		fclose (fh);
+		return (-1);
+	}
+	fclose (fh);
+
+	entropy = atof (buffer);
+	
+	if (entropy > 0.0)
+		entropy_submit (entropy);
+#endif /* KERNEL_LINUX */
+
+	return (0);
+}
+#endif /* ENTROPY_HAVE_READ */
+
+void module_register (void)
+{
+	plugin_register_data_set (&ds);
+#if ENTROPY_HAVE_READ
+	plugin_register_read ("entropy", entropy_read);
+#endif
+}
-- 
2.11.0