From: Florian Forster <octo@noris.net>
Date: Tue, 13 Nov 2007 16:55:50 +0000 (+0000)
Subject: collectd: The new `FQDNLookup' option controls whether or not the FQDN should be... 
X-Git-Tag: collectd-4.3.0beta0~105^2
X-Git-Url: https://git.verplant.org/?a=commitdiff_plain;h=6c9b15cd22b4c1f56b5012b89dd12f0996fa0e4e;p=collectd.git

collectd: The new `FQDNLookup' option controls whether or not the FQDN should be used.

So far the hostname as returned by `gethostname(2)' was used. This is not
practical for large setups.

To stay backwards compatible the option is disabled by default, but the sample
config file includes a line which sets this option so that (new) default
installations will have it enabled.
---

diff --git a/src/collectd.c b/src/collectd.c
index 4e18fd6e..70223b7d 100644
--- a/src/collectd.c
+++ b/src/collectd.c
@@ -23,6 +23,10 @@
 #include "collectd.h"
 #include "common.h"
 
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netdb.h>
+
 #include "plugin.h"
 #include "configfile.h"
 #include "types_list.h"
@@ -48,25 +52,63 @@ static void sigTermHandler (int signal)
 	loop++;
 }
 
-static int init_global_variables (void)
+static int init_hostname (void)
 {
 	const char *str;
 
+	struct addrinfo  ai_hints;
+	struct addrinfo *ai_list;
+	struct addrinfo *ai_ptr;
+	int status;
+
 	str = global_option_get ("Hostname");
 	if (str != NULL)
 	{
 		strncpy (hostname_g, str, sizeof (hostname_g));
+		hostname_g[sizeof (hostname_g) - 1] = '\0';
+		return (0);
 	}
-	else
+
+	if (gethostname (hostname_g, sizeof (hostname_g)) != 0)
 	{
-		if (gethostname (hostname_g, sizeof (hostname_g)) != 0)
-		{
-			fprintf (stderr, "`gethostname' failed and no "
-					"hostname was configured.\n");
-			return (-1);
-		}
+		fprintf (stderr, "`gethostname' failed and no "
+				"hostname was configured.\n");
+		return (-1);
+	}
+
+	str = global_option_get ("FQDNLookup");
+	if ((strcasecmp ("false", str) == 0)
+			|| (strcasecmp ("no", str) == 0)
+			|| (strcasecmp ("off", str) == 0))
+		return (0);
+
+	memset (&ai_hints, '\0', sizeof (ai_hints));
+	ai_hints.ai_flags = AI_CANONNAME;
+
+	status = getaddrinfo (hostname_g, NULL, &ai_hints, &ai_list);
+	if (status != 0)
+	{
+		ERROR ("getaddrinfo failed.");
+		return (-1);
 	}
-	DEBUG ("hostname_g = %s;", hostname_g);
+
+	for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
+	{
+		if (ai_ptr->ai_canonname == NULL)
+			continue;
+
+		strncpy (hostname_g, ai_ptr->ai_canonname, sizeof (hostname_g));
+		hostname_g[sizeof (hostname_g) - 1] = '\0';
+		break;
+	}
+
+	freeaddrinfo (ai_list);
+	return (0);
+} /* int init_hostname */
+
+static int init_global_variables (void)
+{
+	const char *str;
 
 	str = global_option_get ("Interval");
 	if (str == NULL)
@@ -80,6 +122,10 @@ static int init_global_variables (void)
 	}
 	DEBUG ("interval_g = %i;", interval_g);
 
+	if (init_hostname () != 0)
+		return (-1);
+	DEBUG ("hostname_g = %s;", hostname_g);
+
 	return (0);
 } /* int init_global_variables */
 
diff --git a/src/collectd.conf.in b/src/collectd.conf.in
index 58de5258..61789990 100644
--- a/src/collectd.conf.in
+++ b/src/collectd.conf.in
@@ -5,6 +5,7 @@
 #
 
 #Hostname    "localhost"
+FQDNLookup   true
 #BaseDir     "@prefix@/var/lib/@PACKAGE_NAME@"
 #PIDFile     "@prefix@/var/run/@PACKAGE_NAME@.pid"
 #PluginDir   "@prefix@/lib/@PACKAGE_NAME@"
diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index da12f863..d33b2806 100644
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -83,6 +83,23 @@ you may want to increase this if you have more than five plugins that take a
 long time to read. Mostly those are plugin that do network-IO. Setting this to
 a value higher than the number of plugins you've loaded is totally useless.
 
+=item B<Hostname> I<Name>
+
+Sets the hostname that identifies a host. If you omit this setting, the
+hostname will be determinded using the L<gethostname(2)> system call.
+
+=item B<FQDNLookup> B<true|false>
+
+If B<Hostname> is determined automatically this setting controls whether or not
+the daemon should try to figure out the "full qualified domain name", FQDN.
+This is done using a lookup of the name returned by C<gethostname>.
+
+Using this feature (i.E<nbsp>e. setting this option to B<true>) is recommended.
+However, to preserve backwards compatibility the default is set to B<false>.
+The sample config file that is installed with C<makeE<nbsp>install> includes a
+line with sets this option, though, so that default installations will have
+this setting enabled.
+
 =back
 
 =head1 PLUGIN OPTIONS
diff --git a/src/configfile.c b/src/configfile.c
index 0310ca8a..a04a10d5 100644
--- a/src/configfile.c
+++ b/src/configfile.c
@@ -83,12 +83,13 @@ static int cf_value_map_num = STATIC_ARRAY_LEN (cf_value_map);
 
 static cf_global_option_t cf_global_options[] =
 {
-	{"BaseDir",   NULL, PKGLOCALSTATEDIR},
-	{"PIDFile",   NULL, PIDFILE},
-	{"Hostname",  NULL, NULL},
-	{"Interval",  NULL, "10"},
+	{"BaseDir",     NULL, PKGLOCALSTATEDIR},
+	{"PIDFile",     NULL, PIDFILE},
+	{"Hostname",    NULL, NULL},
+	{"FQDNLookup",  NULL, "false"},
+	{"Interval",    NULL, "10"},
 	{"ReadThreads", NULL, "5"},
-	{"TypesDB",   NULL, PLUGINDIR"/types.db"} /* FIXME: Configure path */
+	{"TypesDB",     NULL, PLUGINDIR"/types.db"} /* FIXME: Configure path */
 };
 static int cf_global_options_num = STATIC_ARRAY_LEN (cf_global_options);
 
@@ -173,6 +174,13 @@ static int dispatch_global_option (const oconfig_item_t *ci)
 		tmp[127] = '\0';
 		return (global_option_set (ci->key, tmp));
 	}
+	else if (ci->values[0].type == OCONFIG_TYPE_BOOLEAN)
+	{
+		if (ci->values[0].value.boolean)
+			return (global_option_set (ci->key, "true"));
+		else
+			return (global_option_set (ci->key, "false"));
+	}
 
 	return (-1);
 } /* int dispatch_global_option */