2 * collectd - src/plugin.c
3 * Copyright (C) 2005,2006 Florian octo Forster
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 * Florian octo Forster <octo at verplant.org>
29 #include "utils_debug.h"
36 void (*write) (char *host, char *inst, char *val);
37 void (*shutdown) (void);
41 static plugin_t *first_plugin = NULL;
43 extern int operating_mode;
45 static char *plugindir = NULL;
47 char *plugin_get_dir (void)
49 if (plugindir == NULL)
55 void plugin_set_dir (const char *dir)
57 if (plugindir != NULL)
62 else if ((plugindir = strdup (dir)) == NULL)
63 syslog (LOG_ERR, "strdup: %s", strerror (errno));
67 * Returns the number of plugins registered
69 int plugin_count (void)
74 for (i = 0, p = first_plugin; p != NULL; p = p->next)
81 * Returns the plugins with the type `type' or NULL if it's not found.
83 plugin_t *plugin_search (const char *type)
90 for (ret = first_plugin; ret != NULL; ret = ret->next)
91 if (strcmp (ret->type, type) == 0)
98 * Returns true if the plugin is loaded (i.e. `exists') and false otherwise.
99 * This is used in `configfile.c' to skip sections that are not needed..
101 int plugin_exists (char *type)
103 if (plugin_search (type) == NULL)
110 * (Try to) load the shared object `file'. Won't complain if it isn't a shared
111 * object, but it will bitch about a shared object not having a
112 * ``module_register'' symbol..
114 int plugin_load_file (char *file)
117 void (*reg_handle) (void);
119 DBG ("file = %s", file);
122 lt_dlerror (); /* clear errors */
124 if ((dlh = lt_dlopen (file)) == NULL)
126 const char *error = lt_dlerror ();
128 syslog (LOG_ERR, "lt_dlopen failed: %s", error);
129 DBG ("lt_dlopen failed: %s", error);
133 if ((reg_handle = (void (*) (void)) lt_dlsym (dlh, "module_register")) == NULL)
135 syslog (LOG_WARNING, "Couldn't find symbol ``module_register'' in ``%s'': %s\n",
136 file, lt_dlerror ());
147 int plugin_load (const char *type)
151 char filename[BUFSIZE];
152 char typename[BUFSIZE];
158 DBG ("type = %s", type);
160 dir = plugin_get_dir ();
163 /* don't load twice */
164 if (plugin_search (type) != NULL)
167 /* `cpu' should not match `cpufreq'. To solve this we add `.so' to the
168 * type when matching the filename */
169 if (snprintf (typename, BUFSIZE, "%s.so", type) >= BUFSIZE)
171 syslog (LOG_WARNING, "snprintf: truncated: `%s.so'", type);
174 typename_len = strlen (typename);
176 if ((dh = opendir (dir)) == NULL)
178 syslog (LOG_ERR, "opendir (%s): %s", dir, strerror (errno));
182 while ((de = readdir (dh)) != NULL)
184 if (strncasecmp (de->d_name, typename, typename_len))
187 if (snprintf (filename, BUFSIZE, "%s/%s", dir, de->d_name) >= BUFSIZE)
189 syslog (LOG_WARNING, "snprintf: truncated: `%s/%s'", dir, de->d_name);
193 if (lstat (filename, &statbuf) == -1)
195 syslog (LOG_WARNING, "stat %s: %s", filename, strerror (errno));
198 else if (!S_ISREG (statbuf.st_mode))
200 /* don't follow symlinks */
204 if (plugin_load_file (filename) == 0)
218 * (Try to) load all plugins in `dir'. Returns the number of loaded plugins..
220 int plugin_load_all (char *dir)
224 char filename[BUFSIZE];
228 dir = plugin_get_dir ();
230 plugin_set_dir (dir);
232 if ((dh = opendir (dir)) == NULL)
234 syslog (LOG_ERR, "opendir (%s): %s", dir, strerror (errno));
238 while ((de = readdir (dh)) != NULL)
240 if (snprintf (filename, BUFSIZE, "%s/%s", dir, de->d_name) >= BUFSIZE)
242 syslog (LOG_WARNING, "snprintf: truncated: %s/%s", dir, de->d_name);
246 if (lstat (filename, &statbuf) == -1)
248 syslog (LOG_WARNING, "stat %s: %s", filename, strerror (errno));
251 else if (!S_ISREG (statbuf.st_mode))
256 plugin_load_file (filename);
261 return (plugin_count ());
266 * Call `init' on all plugins (if given)
268 void plugin_init_all (void)
272 for (p = first_plugin; p != NULL; p = p->next)
278 * Call `read' on all plugins (if given)
280 void plugin_read_all (const int *loop)
284 for (p = first_plugin; (*loop == 0) && (p != NULL); p = p->next)
290 * Call `shutdown' on all plugins (if given)
292 void plugin_shutdown_all (void)
296 for (p = first_plugin; NULL != p; p = p->next)
297 if (NULL != p->shutdown)
303 * Add plugin to the linked list of registered plugins.
305 void plugin_register (char *type,
308 void (*write) (char *, char *, char *))
312 if (plugin_search (type) != NULL)
316 if (operating_mode != MODE_SERVER)
318 if ((init != NULL) && (read == NULL))
319 syslog (LOG_NOTICE, "Plugin `%s' doesn't provide a read function.", type);
321 if ((p = (plugin_t *) malloc (sizeof (plugin_t))) == NULL)
324 if ((p->type = strdup (type)) == NULL)
336 p->next = first_plugin;
341 * Register the shutdown function (optional).
343 int plugin_register_shutdown (char *type, void (*shutdown) (void))
345 plugin_t *p = plugin_search (type);
350 p->shutdown = shutdown;
355 * Send received data back to the plugin/module which will append DS
356 * definitions and pass it on to ``rrd_update_file''.
358 void plugin_write (char *host, char *type, char *inst, char *val)
362 if ((p = plugin_search (type)) == NULL)
365 if (p->write == NULL)
368 (*p->write) (host, inst, val);
372 * Receive data from the plugin/module and get it somehow to ``plugin_write'':
373 * Either using ``network_send'' (when in network/client mode) or call it
374 * directly (in local mode).
376 void plugin_submit (char *type, char *inst, char *val)
381 if ((type == NULL) || (val == NULL))
383 DBG ("Help! NULL-pointer! type = %s; inst = %s; val = %s;",
384 (type == NULL) ? "(null)" : type,
386 (val == NULL) ? "(null)" : val);
390 if (operating_mode == MODE_CLIENT)
391 network_send (type, inst, val);
393 plugin_write (NULL, type, inst, val);
396 void plugin_complain (int level, complain_t *c, const char *format, ...)
408 step = atoi (COLLECTD_STEP);
411 if (c->interval < step)
416 if (c->interval > 86400)
419 c->delay = c->interval / step;
421 va_start (ap, format);
422 vsnprintf (message, 512, format, ap);
426 syslog (level, message);
429 void plugin_relief (int level, complain_t *c, const char *format, ...)
434 if (c->interval == 0)
439 va_start (ap, format);
440 vsnprintf (message, 512, format, ap);
444 syslog (level, message);