--- /dev/null
+/**
+ * collectd - src/unixsock.c
+ * Copyright (C) 2007 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
+ *
+ * Author:
+ * Florian octo Forster <octo at verplant.org>
+ **/
+
+#include "collectd.h"
+#include "common.h"
+#include "plugin.h"
+#include "configfile.h"
+#include "utils_debug.h"
+
+/* Folks without pthread will need to disable this plugin. */
+#include <pthread.h>
+
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/poll.h>
+
+#include <grp.h>
+
+#ifndef UNIX_PATH_MAX
+# 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;
+ time_t time;
+ struct value_cache_s *next;
+} value_cache_t;
+
+/*
+ * Private variables
+ */
+/* valid configuration file keys */
+static const char *config_keys[] =
+{
+ "SocketFile",
+ "SocketGroup",
+ "SocketPerms",
+ NULL
+};
+static int config_keys_num = 3;
+
+/* socket configuration */
+static int sock_fd = -1;
+static char *sock_file = NULL;
+static char *sock_group = NULL;
+static int sock_perms = S_IRWXU | S_IRWXG;
+
+static pthread_t listen_thread = -1;
+
+/* 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_alloc_name (char *ret, int ret_len,
+ const char *plugin, const char *plugin_instance,
+ const char *type, const char *type_instance)
+{
+ int status;
+
+ assert (plugin != NULL);
+ assert (type != NULL);
+
+ if ((plugin_instance == NULL) || (strlen (plugin_instance) == 0))
+ {
+ if ((type_instance == NULL) || (strlen (type_instance) == 0))
+ status = snprintf (ret, ret_len, "%s/%s",
+ plugin, type);
+ else
+ status = snprintf (ret, ret_len, "%s/%s-%s",
+ plugin, type, type_instance);
+ }
+ else
+ {
+ if ((type_instance == NULL) || (strlen (type_instance) == 0))
+ status = snprintf (ret, ret_len, "%s-%s/%s",
+ plugin, plugin_instance, type);
+ else
+ status = snprintf (ret, ret_len, "%s-%s/%s-%s",
+ plugin, plugin_instance,
+ type, type_instance);
+ }
+
+ if ((status < 1) || (status >= ret_len))
+ return (-1);
+ return (0);
+} /* int cache_alloc_name */
+
+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;
+
+ DBG ("ds->ds_num = %i; vl->values_len = %i;",
+ ds->ds_num, vl->values_len);
+ assert (ds->ds_num == vl->values_len);
+
+ vc = (value_cache_t *) malloc (sizeof (value_cache_t));
+ if (vc == NULL)
+ {
+ pthread_mutex_unlock (&cache_lock);
+ syslog (LOG_ERR, "unixsock plugin: malloc failed: %s",
+ strerror (errno));
+ return (-1);
+ }
+
+ vc->gauge = (gauge_t *) malloc (sizeof (gauge_t) * vl->values_len);
+ if (vc->gauge == NULL)
+ {
+ pthread_mutex_unlock (&cache_lock);
+ syslog (LOG_ERR, "unixsock plugin: malloc failed: %s",
+ strerror (errno));
+ free (vc);
+ return (-1);
+ }
+
+ vc->counter = (counter_t *) malloc (sizeof (counter_t) * vl->values_len);
+ if (vc->counter == NULL)
+ {
+ pthread_mutex_unlock (&cache_lock);
+ syslog (LOG_ERR, "unixsock plugin: malloc failed: %s",
+ strerror (errno));
+ free (vc->gauge);
+ free (vc);
+ return (-1);
+ }
+
+ if (cache_alloc_name (vc->name, sizeof (vc->name),
+ vl->plugin, vl->plugin_instance,
+ ds->type, vl->type_instance) != 0)
+ {
+ pthread_mutex_unlock (&cache_lock);
+ syslog (LOG_ERR, "unixsock plugin: cache_alloc_name 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->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 (cache_alloc_name (name, sizeof (name),
+ vl->plugin, vl->plugin_instance,
+ ds->type, vl->type_instance) != 0)
+ return (-1);
+
+ pthread_mutex_lock (&cache_lock);
+
+ vc = cache_search (name);
+
+ if (vc == NULL)
+ return (cache_insert (ds, vl));
+
+ assert (vc->values_num == ds->ds_num);
+ assert (vc->values_num == vl->values_len);
+
+ /*
+ * 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);
+ }
+
+ DBG ("name = %s; old counter: %llu; new counter: %llu; rate: %lf;",
+ name,
+ vc->counter[i], vl->values[i].counter,
+ vc->gauge[i]);
+
+ 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;
+
+ DBG ("name, %s; gauge: %lf;",
+ name, vc->gauge[i]);
+ }
+ else
+ {
+ vc->gauge[i] = NAN;
+ vc->counter[i] = 0;
+ }
+
+ if ((vc->gauge[i] == NAN)
+ || ((ds->ds[i].min != NAN) && (vc->gauge[i] < ds->ds[i].min))
+ || ((ds->ds[i].max != NAN) && (vc->gauge[i] > ds->ds[i].max)))
+ vc->gauge[i] = NAN;
+ } /* for i = 0 .. ds->ds_num */
+
+ 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;
+ int status;
+
+ sock_fd = socket (PF_UNIX, SOCK_STREAM, 0);
+ if (sock_fd < 0)
+ {
+ syslog (LOG_ERR, "unixsock plugin: socket failed: %s",
+ strerror (errno));
+ return (-1);
+ }
+
+ 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);
+ /* unlink (sa.sun_path); */
+
+ status = bind (sock_fd, (struct sockaddr *) &sa, sizeof (sa));
+ if (status != 0)
+ {
+ DBG ("bind failed: %s; sa.sun_path = %s",
+ strerror (errno), sa.sun_path);
+ syslog (LOG_ERR, "unixsock plugin: bind failed: %s",
+ strerror (errno));
+ close (sock_fd);
+ sock_fd = -1;
+ return (-1);
+ }
+
+ status = listen (sock_fd, 8);
+ if (status != 0)
+ {
+ syslog (LOG_ERR, "unixsock plugin: listen failed: %s",
+ strerror (errno));
+ close (sock_fd);
+ sock_fd = -1;
+ return (-1);
+ }
+
+ do
+ {
+ struct group *g;
+
+ errno = 0;
+ g = getgrnam ((sock_group != NULL) ? sock_group : COLLECTD_GRP_NAME);
+
+ if (errno != 0)
+ {
+ syslog (LOG_WARNING, "unixsock plugin: getgrnam (%s) failed: %s",
+ (sock_group != NULL) ? sock_group : COLLECTD_GRP_NAME,
+ strerror (errno));
+ break;
+ }
+
+ if (g == NULL)
+ break;
+
+ if (chown ((sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
+ (uid_t) -1, g->gr_gid) != 0)
+ {
+ syslog (LOG_WARNING, "unixsock plugin: chown (%s, -1, %i) failed: %s",
+ (sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
+ (int) g->gr_gid,
+ strerror (errno));
+ }
+ } while (0);
+
+ return (0);
+} /* int us_open_socket */
+
+static int us_handle_getval (FILE *fh, char **fields, int fields_num)
+{
+ char *plugin = fields[1];
+ 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)
+ return (-1);
+
+ type = strchr (plugin, '/');
+ if (type == NULL)
+ return (-1);
+ *type = '\0'; type++;
+
+ plugin_instance = strchr (plugin, '-');
+ if (plugin_instance != NULL)
+ {
+ *plugin_instance = '\0';
+ plugin_instance++;
+ }
+
+ type_instance = strchr (type, '-');
+ if (type_instance != NULL)
+ {
+ *type_instance = '\0';
+ type_instance++;
+ }
+
+ status = cache_alloc_name (name, sizeof (name),
+ plugin, plugin_instance, type, type_instance);
+ if (status != 0)
+ return (-1);
+
+ pthread_mutex_lock (&cache_lock);
+
+ vc = cache_search (name);
+
+ fprintf (fh, "%i", vc->values_num);
+ for (i = 0; i < vc->values_num; i++)
+ {
+ if (vc->gauge[i] == NAN)
+ fprintf (fh, " NaN");
+ else
+ fprintf (fh, " %12e", vc->gauge[i]);
+ }
+
+ /* 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 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;
+
+ DBG ("Reading from fd #%i", fd);
+
+ fh = fdopen (fd, "r+");
+ if (fh == NULL)
+ {
+ syslog (LOG_ERR, "unixsock plugin: fdopen failed: %s",
+ strerror (errno));
+ close (fd);
+ pthread_exit ((void *) 1);
+ }
+
+ while (fgets (buffer, sizeof (buffer), fh) != NULL)
+ {
+ DBG ("fgets -> buffer = %s", buffer);
+
+ fields_num = strsplit (buffer, fields,
+ sizeof (fields) / sizeof (fields[0]));
+
+ if (fields_num < 1)
+ {
+ close (fd);
+ break;
+ }
+
+ if (strcasecmp (fields[0], "getval") == 0)
+ {
+ us_handle_getval (fh, fields, fields_num);
+ }
+ else
+ {
+ fprintf (fh, "Unknown command: %s\n", fields[0]);
+ fflush (fh);
+ }
+ } /* while (fgets) */
+
+ DBG ("Exiting..");
+ close (fd);
+
+ pthread_exit ((void *) 0);
+} /* void *us_handle_client */
+
+static void *us_server_thread (void *arg)
+{
+ int status;
+ int *remote_fd;
+ pthread_t th;
+
+ if (us_open_socket () != 0)
+ pthread_exit ((void *) 1);
+
+ while (42)
+ {
+ DBG ("Calling accept..");
+ status = accept (sock_fd, NULL, NULL);
+ if (status < 0)
+ {
+ if (errno == EINTR)
+ continue;
+
+ syslog (LOG_ERR, "unixsock plugin: accept failed: %s",
+ strerror (errno));
+ close (sock_fd);
+ sock_fd = -1;
+ pthread_exit ((void *) 1);
+ }
+
+ remote_fd = (int *) malloc (sizeof (int));
+ if (remote_fd == NULL)
+ {
+ syslog (LOG_WARNING, "unixsock plugin: malloc failed: %s",
+ strerror (errno));
+ close (status);
+ continue;
+ }
+ *remote_fd = status;
+
+ DBG ("Spawning child to handle connection on fd #%i", *remote_fd);
+
+ status = pthread_create (&th, NULL, us_handle_client, (void *) remote_fd);
+ if (status != 0)
+ {
+ syslog (LOG_WARNING, "unixsock plugin: pthread_create failed: %s",
+ strerror (status));
+ close (*remote_fd);
+ free (remote_fd);
+ continue;
+ }
+ } /* while (42) */
+
+ return ((void *) 0);
+} /* void *us_server_thread */
+
+static int us_config (const char *key, const char *val)
+{
+ if (strcasecmp (key, "SocketFile") == 0)
+ {
+ sfree (sock_file);
+ sock_file = strdup (val);
+ }
+ else if (strcasecmp (key, "SocketGroup") == 0)
+ {
+ sfree (sock_group);
+ sock_group = strdup (val);
+ }
+ else if (strcasecmp (key, "SocketPerms") == 0)
+ {
+ sock_perms = (int) strtol (val, NULL, 8);
+ }
+ else
+ {
+ return (-1);
+ }
+
+ return (0);
+} /* int us_config */
+
+static int us_init (void)
+{
+ int status;
+
+ status = pthread_create (&listen_thread, NULL, us_server_thread, NULL);
+ if (status != 0)
+ {
+ syslog (LOG_ERR, "unixsock plugin: pthread_create failed: %s",
+ strerror (status));
+ return (-1);
+ }
+
+ return (0);
+} /* int us_init */
+
+static int us_shutdown (void)
+{
+ void *ret;
+
+ if (listen_thread >= 0)
+ {
+ pthread_kill (listen_thread, SIGTERM);
+ pthread_join (listen_thread, &ret);
+ }
+
+ 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 * atoi (COLLECTD_STEP));
+
+ 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) */
+
+/* vim: set sw=4 ts=4 sts=4 tw=78 : */
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