X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=src%2Funixsock.c;h=0b897482c9d956547d74be3f905f9d9941b157be;hb=3b4201d2235c25ed21174c41c526c9b7894de539;hp=734403e87c944fb606670f205e0e5b43a479bd75;hpb=7e5df1a2c6611bd4ac9fb8ac4b78106f9139ae6e;p=collectd.git

diff --git a/src/unixsock.c b/src/unixsock.c
index 734403e8..0b897482 100644
--- a/src/unixsock.c
+++ b/src/unixsock.c
@@ -1,6 +1,6 @@
 /**
  * collectd - src/unixsock.c
- * Copyright (C) 2007  Florian octo Forster
+ * Copyright (C) 2007,2008  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
@@ -24,10 +24,18 @@
 #include "plugin.h"
 #include "configfile.h"
 
+#include "utils_cmd_flush.h"
+#include "utils_cmd_getval.h"
+#include "utils_cmd_getthreshold.h"
+#include "utils_cmd_listval.h"
+#include "utils_cmd_putval.h"
+#include "utils_cmd_putnotif.h"
+
 /* Folks without pthread will need to disable this plugin. */
 #include <pthread.h>
 
 #include <sys/socket.h>
+#include <sys/stat.h>
 #include <sys/un.h>
 
 #include <grp.h>
@@ -36,22 +44,7 @@
 # define UNIX_PATH_MAX sizeof (((struct sockaddr_un *)0)->sun_path)
 #endif
 
-#define US_DEFAULT_PATH PREFIX"/var/run/"PACKAGE_NAME"-unixsock"
-
-/*
- * Private data structures
- */
-/* linked list of cached values */
-typedef struct value_cache_s
-{
-	char       name[4*DATA_MAX_NAME_LEN];
-	int        values_num;
-	gauge_t   *gauge;
-	counter_t *counter;
-	const data_set_t *ds;
-	time_t     time;
-	struct value_cache_s *next;
-} value_cache_t;
+#define US_DEFAULT_PATH LOCALSTATEDIR"/run/"PACKAGE_NAME"-unixsock"
 
 /*
  * Private variables
@@ -61,10 +54,9 @@ static const char *config_keys[] =
 {
 	"SocketFile",
 	"SocketGroup",
-	"SocketPerms",
-	NULL
+	"SocketPerms"
 };
-static int config_keys_num = 3;
+static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
 
 static int loop = 0;
 
@@ -76,261 +68,9 @@ static int   sock_perms = S_IRWXU | S_IRWXG;
 
 static pthread_t listen_thread = (pthread_t) 0;
 
-/* Linked list and auxilliary variables for saving values */
-static value_cache_t   *cache_head = NULL;
-static pthread_mutex_t  cache_lock = PTHREAD_MUTEX_INITIALIZER;
-static unsigned int     cache_oldest = UINT_MAX;
-
 /*
  * Functions
  */
-static value_cache_t *cache_search (const char *name)
-{
-	value_cache_t *vc;
-
-	for (vc = cache_head; vc != NULL; vc = vc->next)
-	{
-		if (strcmp (vc->name, name) == 0)
-			break;
-	} /* for vc = cache_head .. NULL */
-
-	return (vc);
-} /* value_cache_t *cache_search */
-
-static int cache_insert (const data_set_t *ds, const value_list_t *vl)
-{
-	/* We're called from `cache_update' so we don't need to lock the mutex */
-	value_cache_t *vc;
-	int i;
-
-	DEBUG ("unixsock plugin: cache_insert: ds->type = %s; ds->ds_num = %i;"
-			" vl->values_len = %i;",
-			ds->type, ds->ds_num, vl->values_len);
-#if COLLECT_DEBUG
-	assert (ds->ds_num == vl->values_len);
-#else
-	if (ds->ds_num != vl->values_len)
-	{
-		ERROR ("unixsock plugin: ds->type = %s: (ds->ds_num = %i) != "
-				"(vl->values_len = %i)",
-				ds->type, ds->ds_num, vl->values_len);
-		return (-1);
-	}
-#endif
-
-	vc = (value_cache_t *) malloc (sizeof (value_cache_t));
-	if (vc == NULL)
-	{
-		char errbuf[1024];
-		pthread_mutex_unlock (&cache_lock);
-		ERROR ("unixsock plugin: malloc failed: %s",
-				sstrerror (errno, errbuf, sizeof (errbuf)));
-		return (-1);
-	}
-
-	vc->gauge = (gauge_t *) malloc (sizeof (gauge_t) * vl->values_len);
-	if (vc->gauge == NULL)
-	{
-		char errbuf[1024];
-		pthread_mutex_unlock (&cache_lock);
-		ERROR ("unixsock plugin: malloc failed: %s",
-				sstrerror (errno, errbuf, sizeof (errbuf)));
-		free (vc);
-		return (-1);
-	}
-
-	vc->counter = (counter_t *) malloc (sizeof (counter_t) * vl->values_len);
-	if (vc->counter == NULL)
-	{
-		char errbuf[1024];
-		pthread_mutex_unlock (&cache_lock);
-		ERROR ("unixsock plugin: malloc failed: %s",
-				sstrerror (errno, errbuf, sizeof (errbuf)));
-		free (vc->gauge);
-		free (vc);
-		return (-1);
-	}
-
-	if (FORMAT_VL (vc->name, sizeof (vc->name), vl, ds))
-	{
-		pthread_mutex_unlock (&cache_lock);
-		ERROR ("unixsock plugin: FORMAT_VL failed.");
-		free (vc->counter);
-		free (vc->gauge);
-		free (vc);
-		return (-1);
-	}
-
-	for (i = 0; i < ds->ds_num; i++)
-	{
-		if (ds->ds[i].type == DS_TYPE_COUNTER)
-		{
-			vc->gauge[i] = 0.0;
-			vc->counter[i] = vl->values[i].counter;
-		}
-		else if (ds->ds[i].type == DS_TYPE_GAUGE)
-		{
-			vc->gauge[i] = vl->values[i].gauge;
-			vc->counter[i] = 0;
-		}
-		else
-		{
-			vc->gauge[i] = 0.0;
-			vc->counter[i] = 0;
-		}
-	}
-	vc->values_num = ds->ds_num;
-	vc->ds = ds;
-
-	vc->next = cache_head;
-	cache_head = vc;
-
-	vc->time = vl->time;
-	if (vc->time < cache_oldest)
-		cache_oldest = vc->time;
-
-	pthread_mutex_unlock (&cache_lock);
-	return (0);
-} /* int cache_insert */
-
-static int cache_update (const data_set_t *ds, const value_list_t *vl)
-{
-	char name[4*DATA_MAX_NAME_LEN];;
-	value_cache_t *vc;
-	int i;
-
-	if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
-		return (-1);
-
-	pthread_mutex_lock (&cache_lock);
-
-	vc = cache_search (name);
-
-	/* pthread_mutex_lock is called by cache_insert. */
-	if (vc == NULL)
-		return (cache_insert (ds, vl));
-
-	assert (vc->values_num == ds->ds_num);
-	assert (vc->values_num == vl->values_len);
-
-	/* Avoid floating-point exceptions due to division by zero. */
-	if (vc->time >= vl->time)
-	{
-		pthread_mutex_unlock (&cache_lock);
-		ERROR ("unixsock plugin: vc->time >= vl->time. vc->time = %u; "
-				"vl->time = %u; vl = %s;",
-				(unsigned int) vc->time, (unsigned int) vl->time,
-				name);
-		return (-1);
-	} /* if (vc->time >= vl->time) */
-
-	/*
-	 * Update the values. This is possibly a lot more that you'd expect
-	 * because we honor min and max values and handle counter overflows here.
-	 */
-	for (i = 0; i < ds->ds_num; i++)
-	{
-		if (ds->ds[i].type == DS_TYPE_COUNTER)
-		{
-			if (vl->values[i].counter < vc->counter[i])
-			{
-				if (vl->values[i].counter <= 4294967295U)
-				{
-					vc->gauge[i] = ((4294967295U - vl->values[i].counter)
-							+ vc->counter[i]) / (vl->time - vc->time);
-				}
-				else
-				{
-					vc->gauge[i] = ((18446744073709551615ULL - vl->values[i].counter)
-						+ vc->counter[i]) / (vl->time - vc->time);
-				}
-			}
-			else
-			{
-				vc->gauge[i] = (vl->values[i].counter - vc->counter[i])
-					/ (vl->time - vc->time);
-			}
-
-			vc->counter[i] = vl->values[i].counter;
-		}
-		else if (ds->ds[i].type == DS_TYPE_GAUGE)
-		{
-			vc->gauge[i] = vl->values[i].gauge;
-			vc->counter[i] = 0;
-		}
-		else
-		{
-			vc->gauge[i] = NAN;
-			vc->counter[i] = 0;
-		}
-
-		if (isnan (vc->gauge[i])
-				|| (!isnan (ds->ds[i].min) && (vc->gauge[i] < ds->ds[i].min))
-				|| (!isnan (ds->ds[i].max) && (vc->gauge[i] > ds->ds[i].max)))
-			vc->gauge[i] = NAN;
-	} /* for i = 0 .. ds->ds_num */
-
-	vc->ds = ds;
-	vc->time = vl->time;
-
-	if (vc->time < cache_oldest)
-		cache_oldest = vc->time;
-
-	pthread_mutex_unlock (&cache_lock);
-	return (0);
-} /* int cache_update */
-
-static void cache_flush (int max_age)
-{
-	value_cache_t *this;
-	value_cache_t *prev;
-	time_t now;
-
-	pthread_mutex_lock (&cache_lock);
-
-	now = time (NULL);
-
-	if ((now - cache_oldest) <= max_age)
-	{
-		pthread_mutex_unlock (&cache_lock);
-		return;
-	}
-	
-	cache_oldest = now;
-
-	prev = NULL;
-	this = cache_head;
-
-	while (this != NULL)
-	{
-		if ((now - this->time) <= max_age)
-		{
-			if (this->time < cache_oldest)
-				cache_oldest = this->time;
-
-			prev = this;
-			this = this->next;
-			continue;
-		}
-
-		if (prev == NULL)
-			cache_head = this->next;
-		else
-			prev->next = this->next;
-
-		free (this->gauge);
-		free (this->counter);
-		free (this);
-
-		if (prev == NULL)
-			this = cache_head;
-		else
-			this = prev->next;
-	} /* while (this != NULL) */
-
-	pthread_mutex_unlock (&cache_lock);
-} /* int cache_flush */
-
 static int us_open_socket (void)
 {
 	struct sockaddr_un sa;
@@ -347,8 +87,8 @@ static int us_open_socket (void)
 
 	memset (&sa, '\0', sizeof (sa));
 	sa.sun_family = AF_UNIX;
-	strncpy (sa.sun_path, (sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
-			sizeof (sa.sun_path) - 1);
+	sstrncpy (sa.sun_path, (sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
+			sizeof (sa.sun_path));
 	/* unlink (sa.sun_path); */
 
 	DEBUG ("unixsock plugin: socket path = %s", sa.sun_path);
@@ -364,6 +104,8 @@ static int us_open_socket (void)
 		return (-1);
 	}
 
+	chmod (sa.sun_path, sock_perms);
+
 	status = listen (sock_fd, 8);
 	if (status != 0)
 	{
@@ -414,250 +156,81 @@ static int us_open_socket (void)
 	return (0);
 } /* int us_open_socket */
 
-static int us_handle_getval (FILE *fh, char **fields, int fields_num)
+static void *us_handle_client (void *arg)
 {
-	char *hostname;
-	char *plugin;
-	char *plugin_instance;
-	char *type;
-	char *type_instance;
-	char  name[4*DATA_MAX_NAME_LEN];
-	value_cache_t *vc;
-	int   status;
-	int   i;
-
-	if (fields_num != 2)
-	{
-		DEBUG ("unixsock plugin: Wrong number of fields: %i", fields_num);
-		fprintf (fh, "-1 Wrong number of fields: Got %i, expected 2.\n",
-				fields_num);
-		fflush (fh);
-		return (-1);
-	}
-	DEBUG ("unixsock plugin: Got query for `%s'", fields[1]);
+	int fdin;
+	int fdout;
+	FILE *fhin, *fhout;
 
-	status = parse_identifier (fields[1], &hostname,
-			&plugin, &plugin_instance,
-			&type, &type_instance);
-	if (status != 0)
-	{
-		DEBUG ("unixsock plugin: Cannot parse `%s'", fields[1]);
-		fprintf (fh, "-1 Cannot parse identifier.\n");
-		fflush (fh);
-		return (-1);
-	}
-
-	status = format_name (name, sizeof (name),
-			hostname, plugin, plugin_instance, type, type_instance);
-	if (status != 0)
-	{
-		fprintf (fh, "-1 format_name failed.\n");
-		return (-1);
-	}
-
-	pthread_mutex_lock (&cache_lock);
+	fdin = *((int *) arg);
+	free (arg);
+	arg = NULL;
 
-	DEBUG ("vc = cache_search (%s)", name);
-	vc = cache_search (name);
+	DEBUG ("unixsock plugin: us_handle_client: Reading from fd #%i", fdin);
 
-	if (vc == NULL)
-	{
-		DEBUG ("Did not find cache entry.");
-		fprintf (fh, "-1 No such value");
-	}
-	else
+	fdout = dup (fdin);
+	if (fdout < 0)
 	{
-		DEBUG ("Found cache entry.");
-		fprintf (fh, "%i", vc->values_num);
-		for (i = 0; i < vc->values_num; i++)
-		{
-			fprintf (fh, " %s=", vc->ds->ds[i].name);
-			if (isnan (vc->gauge[i]))
-				fprintf (fh, "NaN");
-			else
-				fprintf (fh, "%12e", vc->gauge[i]);
-		}
+		char errbuf[1024];
+		ERROR ("unixsock plugin: dup failed: %s",
+				sstrerror (errno, errbuf, sizeof (errbuf)));
+		close (fdin);
+		pthread_exit ((void *) 1);
 	}
 
-	/* Free the mutex as soon as possible and definitely before flushing */
-	pthread_mutex_unlock (&cache_lock);
-
-	fprintf (fh, "\n");
-	fflush (fh);
-
-	return (0);
-} /* int us_handle_getval */
-
-static int us_handle_putval (FILE *fh, char **fields, int fields_num)
-{
-	char *hostname;
-	char *plugin;
-	char *plugin_instance;
-	char *type;
-	char *type_instance;
-	int   status;
-	int   i;
-
-	const data_set_t *ds;
-	value_list_t vl = VALUE_LIST_INIT;
-
-	char **value_ptr;
-
-	if (fields_num != 3)
+	fhin  = fdopen (fdin, "r");
+	if (fhin == NULL)
 	{
-		DEBUG ("unixsock plugin: Wrong number of fields: %i", fields_num);
-		fprintf (fh, "-1 Wrong number of fields: Got %i, expected 3.\n",
-				fields_num);
-		fflush (fh);
-		return (-1);
+		char errbuf[1024];
+		ERROR ("unixsock plugin: fdopen failed: %s",
+				sstrerror (errno, errbuf, sizeof (errbuf)));
+		close (fdin);
+		close (fdout);
+		pthread_exit ((void *) 1);
 	}
 
-	status = parse_identifier (fields[1], &hostname,
-			&plugin, &plugin_instance,
-			&type, &type_instance);
-	if (status != 0)
+	fhout = fdopen (fdout, "w");
+	if (fhout == NULL)
 	{
-		DEBUG ("unixsock plugin: Cannot parse `%s'", fields[1]);
-		fprintf (fh, "-1 Cannot parse identifier.\n");
-		fflush (fh);
-		return (-1);
+		char errbuf[1024];
+		ERROR ("unixsock plugin: fdopen failed: %s",
+				sstrerror (errno, errbuf, sizeof (errbuf)));
+		fclose (fhin); /* this closes fdin as well */
+		close (fdout);
+		pthread_exit ((void *) 1);
 	}
 
-	if ((strlen (hostname) >= sizeof (vl.host))
-			|| (strlen (plugin) >= sizeof (vl.plugin))
-			|| ((plugin_instance != NULL)
-				&& (strlen (plugin_instance) >= sizeof (vl.plugin_instance)))
-			|| ((type_instance != NULL)
-				&& (strlen (type_instance) >= sizeof (vl.type_instance))))
+	/* change output buffer to line buffered mode */
+	if (setvbuf (fhout, NULL, _IOLBF, 0) != 0)
 	{
-		fprintf (fh, "-1 Identifier too long.");
-		return (-1);
-	}
-
-	strcpy (vl.host, hostname);
-	strcpy (vl.plugin, plugin);
-	if (plugin_instance != NULL)
-		strcpy (vl.plugin_instance, plugin_instance);
-	if (type_instance != NULL)
-		strcpy (vl.type_instance, type_instance);
-
-	{ /* parse the time */
-		char *t = fields[2];
-		char *v = strchr (t, ':');
-		if (v == NULL)
-		{
-			fprintf (fh, "-1 No time found.");
-			return (-1);
-		}
-		*v = '\0'; v++;
-
-		vl.time = (time_t) atoi (t);
-		if (vl.time == 0)
-			vl.time = time (NULL);
-
-		fields[2] = v;
+		char errbuf[1024];
+		ERROR ("unixsock plugin: setvbuf failed: %s",
+				sstrerror (errno, errbuf, sizeof (errbuf)));
+		fclose (fhin);
+		fclose (fhout);
+		pthread_exit ((void *) 1);
 	}
 
-	ds = plugin_get_ds (type);
-	if (ds == NULL)
-		return (-1);
-
-	value_ptr = (char **) calloc (ds->ds_num, sizeof (char *));
-	if (value_ptr == NULL)
+	while (42)
 	{
-		fprintf (fh, "-1 calloc failed.");
-		return (-1);
-	}
+		char buffer[1024];
+		char buffer_copy[1024];
+		char *fields[128];
+		int   fields_num;
+		int   len;
 
-	{ /* parse the value-list. It's colon-separated. */
-		char *dummy;
-		char *ptr;
-		char *saveptr;
-
-		i = 0;
-		dummy = fields[2];
-		saveptr = NULL;
-		while ((ptr = strtok_r (dummy, ":", &saveptr)) != NULL)
+		errno = 0;
+		if (fgets (buffer, sizeof (buffer), fhin) == NULL)
 		{
-			dummy = NULL;
-			if (i >= ds->ds_num)
+			if (errno != 0)
 			{
-				i = ds->ds_num + 1;
-				break;
+				char errbuf[1024];
+				WARNING ("unixsock plugin: failed to read from socket #%i: %s",
+						fileno (fhin),
+						sstrerror (errno, errbuf, sizeof (errbuf)));
 			}
-			value_ptr[i] = ptr;
-			i++;
-		}
-
-		if (i != ds->ds_num)
-		{
-			sfree (value_ptr);
-			fprintf (fh, "-1 Number of values incorrect: Got %i, "
-					"expected %i.", i, ds->ds_num);
-			return (-1);
+			break;
 		}
-	} /* done parsing the value-list */
-
-	vl.values_len = ds->ds_num;
-	vl.values = (value_t *) malloc (vl.values_len * sizeof (value_t));
-	if (vl.values == NULL)
-	{
-		sfree (value_ptr);
-		fprintf (fh, "-1 malloc failed.");
-		return (-1);
-	}
-	DEBUG ("value_ptr = 0x%p; vl.values = 0x%p;", (void *) value_ptr, (void *) vl.values);
-
-	for (i = 0; i < ds->ds_num; i++)
-	{
-		if (strcmp (value_ptr[i], "U") == 0)
-			vl.values[i].gauge = NAN;
-		else if (ds->ds[i].type == DS_TYPE_COUNTER)
-			vl.values[i].counter = atoll (value_ptr[i]);
-		else if (ds->ds[i].type == DS_TYPE_GAUGE)
-			vl.values[i].gauge = atof (value_ptr[i]);
-	} /* for (i = 2 .. fields_num) */
-
-	plugin_dispatch_values (type, &vl);
-
-	DEBUG ("value_ptr = 0x%p; vl.values = 0x%p;", (void *) value_ptr, (void *) vl.values);
-
-	sfree (value_ptr);
-	sfree (vl.values); 
-
-	fprintf (fh, "0 Success\n");
-	fflush (fh);
-
-	return (0);
-} /* int us_handle_putval */
-
-static void *us_handle_client (void *arg)
-{
-	int fd;
-	FILE *fh;
-	char buffer[1024];
-	char *fields[128];
-	int   fields_num;
-
-	fd = *((int *) arg);
-	free (arg);
-	arg = NULL;
-
-	DEBUG ("Reading from fd #%i", fd);
-
-	fh = fdopen (fd, "r+");
-	if (fh == NULL)
-	{
-		char errbuf[1024];
-		ERROR ("unixsock plugin: fdopen failed: %s",
-				sstrerror (errno, errbuf, sizeof (errbuf)));
-		close (fd);
-		pthread_exit ((void *) 1);
-	}
-
-	while (fgets (buffer, sizeof (buffer), fh) != NULL)
-	{
-		int len;
 
 		len = strlen (buffer);
 		while ((len > 0)
@@ -667,39 +240,64 @@ static void *us_handle_client (void *arg)
 		if (len == 0)
 			continue;
 
-		DEBUG ("fgets -> buffer = %s; len = %i;", buffer, len);
+		sstrncpy (buffer_copy, buffer, sizeof (buffer_copy));
 
-		fields_num = strsplit (buffer, fields,
+		fields_num = strsplit (buffer_copy, fields,
 				sizeof (fields) / sizeof (fields[0]));
-
 		if (fields_num < 1)
 		{
-			close (fd);
-			break;
+			fprintf (fhout, "-1 Internal error\n");
+			fclose (fhin);
+			fclose (fhout);
+			pthread_exit ((void *) 1);
 		}
 
 		if (strcasecmp (fields[0], "getval") == 0)
 		{
-			us_handle_getval (fh, fields, fields_num);
+			handle_getval (fhout, buffer);
+		}
+		else if (strcasecmp (fields[0], "getthreshold") == 0)
+		{
+			handle_getthreshold (fhout, buffer);
 		}
 		else if (strcasecmp (fields[0], "putval") == 0)
 		{
-			us_handle_putval (fh, fields, fields_num);
+			handle_putval (fhout, buffer);
+		}
+		else if (strcasecmp (fields[0], "listval") == 0)
+		{
+			handle_listval (fhout, buffer);
+		}
+		else if (strcasecmp (fields[0], "putnotif") == 0)
+		{
+			handle_putnotif (fhout, buffer);
+		}
+		else if (strcasecmp (fields[0], "flush") == 0)
+		{
+			handle_flush (fhout, buffer);
 		}
 		else
 		{
-			fprintf (fh, "-1 Unknown command: %s\n", fields[0]);
-			fflush (fh);
+			if (fprintf (fhout, "-1 Unknown command: %s\n", fields[0]) < 0)
+			{
+				char errbuf[1024];
+				WARNING ("unixsock plugin: failed to write to socket #%i: %s",
+						fileno (fhout),
+						sstrerror (errno, errbuf, sizeof (errbuf)));
+				break;
+			}
 		}
 	} /* while (fgets) */
 
-	DEBUG ("Exiting..");
-	close (fd);
+	DEBUG ("unixsock plugin: us_handle_client: Exiting..");
+	fclose (fhin);
+	fclose (fhout);
 
 	pthread_exit ((void *) 0);
+	return ((void *) 0);
 } /* void *us_handle_client */
 
-static void *us_server_thread (void *arg)
+static void *us_server_thread (void __attribute__((unused)) *arg)
 {
 	int  status;
 	int *remote_fd;
@@ -711,7 +309,7 @@ static void *us_server_thread (void *arg)
 
 	while (loop != 0)
 	{
-		DEBUG ("Calling accept..");
+		DEBUG ("unixsock plugin: Calling accept..");
 		status = accept (sock_fd, NULL, NULL);
 		if (status < 0)
 		{
@@ -774,13 +372,21 @@ static int us_config (const char *key, const char *val)
 {
 	if (strcasecmp (key, "SocketFile") == 0)
 	{
+		char *new_sock_file = strdup (val);
+		if (new_sock_file == NULL)
+			return (1);
+
 		sfree (sock_file);
-		sock_file = strdup (val);
+		sock_file = new_sock_file;
 	}
 	else if (strcasecmp (key, "SocketGroup") == 0)
 	{
+		char *new_sock_group = strdup (val);
+		if (new_sock_group == NULL)
+			return (1);
+
 		sfree (sock_group);
-		sock_group = strdup (val);
+		sock_group = new_sock_group;
 	}
 	else if (strcasecmp (key, "SocketPerms") == 0)
 	{
@@ -796,8 +402,15 @@ static int us_config (const char *key, const char *val)
 
 static int us_init (void)
 {
+	static int have_init = 0;
+
 	int status;
 
+	/* Initialize only once. */
+	if (have_init != 0)
+		return (0);
+	have_init = 1;
+
 	loop = 1;
 
 	status = pthread_create (&listen_thread, NULL, us_server_thread, NULL);
@@ -826,26 +439,16 @@ static int us_shutdown (void)
 	}
 
 	plugin_unregister_init ("unixsock");
-	plugin_unregister_write ("unixsock");
 	plugin_unregister_shutdown ("unixsock");
 
 	return (0);
 } /* int us_shutdown */
 
-static int us_write (const data_set_t *ds, const value_list_t *vl)
-{
-	cache_update (ds, vl);
-	cache_flush (2 * interval_g);
-
-	return (0);
-}
-
 void module_register (void)
 {
 	plugin_register_config ("unixsock", us_config,
 			config_keys, config_keys_num);
 	plugin_register_init ("unixsock", us_init);
-	plugin_register_write ("unixsock", us_write);
 	plugin_register_shutdown ("unixsock", us_shutdown);
 } /* void module_register (void) */