1 /**
2 * collectd - src/collectd.c
3 * Copyright (C) 2005,2006 Florian octo Forster
4 *
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.
9 *
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.
14 *
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
18 *
19 * Authors:
20 * Florian octo Forster <octo at verplant.org>
21 * Alvaro Barcellos <alvaro.barcellos at gmail.com>
22 **/
24 #include "collectd.h"
25 #include "common.h"
26 #include "utils_debug.h"
28 #include "network.h"
29 #include "plugin.h"
30 #include "configfile.h"
32 static int loop = 0;
34 #if HAVE_LIBKSTAT
35 kstat_ctl_t *kc;
36 #endif /* HAVE_LIBKSTAT */
38 /*
39 * exported variables
40 */
41 time_t curtime;
42 int operating_mode;
44 static void sigIntHandler (int signal)
45 {
46 loop++;
47 }
49 static void sigTermHandler (int signal)
50 {
51 loop++;
52 }
54 static int change_basedir (char *dir)
55 {
56 int dirlen = strlen (dir);
58 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
59 dir[--dirlen] = '\0';
61 if (dirlen <= 0)
62 return (-1);
64 if (chdir (dir) == -1)
65 {
66 if (errno == ENOENT)
67 {
68 if (mkdir (dir, 0755) == -1)
69 {
70 syslog (LOG_ERR, "mkdir (%s): %s", dir, strerror (errno));
71 return (-1);
72 }
73 else if (chdir (dir) == -1)
74 {
75 syslog (LOG_ERR, "chdir (%s): %s", dir, strerror (errno));
76 return (-1);
77 }
78 }
79 else
80 {
81 syslog (LOG_ERR, "chdir: %s", strerror (errno));
82 return (-1);
83 }
84 }
86 return (0);
87 } /* static int change_basedir (char *dir) */
89 #if HAVE_LIBKSTAT
90 static void update_kstat (void)
91 {
92 if (kc == NULL)
93 {
94 if ((kc = kstat_open ()) == NULL)
95 syslog (LOG_ERR, "Unable to open kstat control structure");
96 }
97 else
98 {
99 kid_t kid;
100 kid = kstat_chain_update (kc);
101 if (kid > 0)
102 {
103 syslog (LOG_INFO, "kstat chain has been updated");
104 plugin_init_all ();
105 }
106 else if (kid < 0)
107 syslog (LOG_ERR, "kstat chain update failed");
108 /* else: everything works as expected */
109 }
111 return;
112 } /* static void update_kstat (void) */
113 #endif /* HAVE_LIBKSTAT */
115 /* TODO
116 * Remove all settings but `-f' and `-C'
117 */
118 static void exit_usage (char *name)
119 {
120 printf ("Usage: "PACKAGE" [OPTIONS]\n\n"
122 "Available options:\n"
123 " General:\n"
124 " -C <file> Configuration file.\n"
125 " Default: "CONFIGFILE"\n"
126 " -P <file> PID-file.\n"
127 " Default: "PIDFILE"\n"
128 #if COLLECT_DAEMON
129 " -f Don't fork to the background.\n"
130 #endif
131 "\nBuiltin defaults:\n"
132 " Config-File "CONFIGFILE"\n"
133 " PID-File "PIDFILE"\n"
134 " Data-Directory "PKGLOCALSTATEDIR"\n"
135 #if COLLECT_DEBUG
136 " Log-File "LOGFILE"\n"
137 #endif
138 " Step "COLLECTD_STEP" seconds\n"
139 " Heartbeat "COLLECTD_HEARTBEAT" seconds\n"
140 "\n"PACKAGE" "VERSION", http://collectd.org/\n"
141 "by Florian octo Forster <octo@verplant.org>\n"
142 "for contributions see `AUTHORS'\n");
143 exit (0);
144 } /* static void exit_usage (char *name) */
146 static int start_client (void)
147 {
148 int step;
150 struct timeval tv_now;
151 struct timeval tv_next;
152 struct timespec ts_wait;
154 step = atoi (COLLECTD_STEP);
155 if (step <= 0)
156 step = 10;
158 #if HAVE_LIBKSTAT
159 kc = NULL;
160 update_kstat ();
161 #endif
163 #if HAVE_LIBSTATGRAB
164 if (sg_init ())
165 {
166 syslog (LOG_ERR, "sg_init: %s", sg_str_error (sg_get_error ()));
167 return (-1);
168 }
170 if (sg_drop_privileges ())
171 {
172 syslog (LOG_ERR, "sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
173 return (-1);
174 }
175 #endif
177 plugin_init_all ();
179 while (loop == 0)
180 {
181 if (gettimeofday (&tv_next, NULL) < 0)
182 {
183 syslog (LOG_ERR, "gettimeofday failed: %s", strerror (errno));
184 return (-1);
185 }
186 tv_next.tv_sec += step;
188 #if HAVE_LIBKSTAT
189 update_kstat ();
190 #endif
191 /* `curtime' is used by many (all?) plugins as the
192 * data-sample-time passed to RRDTool */
193 curtime = time (NULL);
195 /* Issue all plugins */
196 plugin_read_all (&loop);
198 if (gettimeofday (&tv_now, NULL) < 0)
199 {
200 syslog (LOG_ERR, "gettimeofday failed: %s", strerror (errno));
201 return (-1);
202 }
204 if (timeval_sub_timespec (&tv_next, &tv_now, &ts_wait) != 0)
205 {
206 syslog (LOG_WARNING, "Not sleeping because `timeval_sub_timespec' returned non-zero!");
207 continue;
208 }
210 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) == -1))
211 {
212 if (errno != EINTR)
213 {
214 syslog (LOG_ERR, "nanosleep failed: %s", strerror (errno));
215 break;
216 }
217 }
218 }
220 return (0);
221 } /* static int start_client (void) */
223 #if HAVE_LIBRRD
224 static int start_server (void)
225 {
226 /* FIXME use stack here! */
227 char *host;
228 char *type;
229 char *instance;
230 char *values;
232 while (loop == 0)
233 {
234 if (network_receive (&host, &type, &instance, &values) == 0)
235 plugin_write (host, type, instance, values);
237 if (host != NULL) free (host); host = NULL;
238 if (type != NULL) free (type); type = NULL;
239 if (instance != NULL) free (instance); instance = NULL;
240 if (values != NULL) free (values); values = NULL;
241 }
243 return (0);
244 } /* static int start_server (void) */
245 #endif /* HAVE_LIBRRD */
247 #if COLLECT_DAEMON
248 static int pidfile_create (const char *file)
249 {
250 FILE *fh;
252 if (file == NULL)
253 file = PIDFILE;
255 if ((fh = fopen (file, "w")) == NULL)
256 {
257 syslog (LOG_ERR, "fopen (%s): %s", file, strerror (errno));
258 return (1);
259 }
261 fprintf (fh, "%i\n", (int) getpid ());
262 fclose(fh);
264 return (0);
265 } /* static int pidfile_create (const char *file) */
266 #endif /* COLLECT_DAEMON */
268 #if COLLECT_DAEMON
269 static int pidfile_remove (const char *file)
270 {
271 if (file == NULL) {
272 file = PIDFILE;
273 }
274 return (unlink (file));
275 } /* static int pidfile_remove (const char *file) */
276 #endif /* COLLECT_DAEMON */
278 int main (int argc, char **argv)
279 {
280 struct sigaction sigIntAction;
281 struct sigaction sigTermAction;
282 char *datadir = PKGLOCALSTATEDIR;
283 char *configfile = CONFIGFILE;
284 #if COLLECT_DAEMON
285 struct sigaction sigChldAction;
286 char *pidfile = NULL;
287 pid_t pid;
288 int daemonize = 1;
289 #endif
290 #if COLLECT_DEBUG
291 char *logfile = LOGFILE;
292 #endif
294 #if HAVE_LIBRRD
295 operating_mode = MODE_LOCAL;
296 #else
297 operating_mode = MODE_CLIENT;
298 #endif
300 /* open syslog */
301 openlog (PACKAGE, LOG_CONS | LOG_PID, LOG_DAEMON);
303 /* read options */
304 while (1)
305 {
306 int c;
308 c = getopt (argc, argv, "hC:"
309 #if COLLECT_DAEMON
310 "fP:"
311 #endif
312 );
314 if (c == -1)
315 break;
317 switch (c)
318 {
319 case 'C':
320 configfile = optarg;
321 break;
322 #if COLLECT_DAEMON
323 case 'P':
324 pidfile = optarg;
325 break;
326 case 'f':
327 daemonize = 0;
328 break;
329 #endif /* COLLECT_DAEMON */
330 case 'h':
331 default:
332 exit_usage (argv[0]);
333 } /* switch (c) */
334 } /* while (1) */
336 #if COLLECT_DEBUG
337 if ((logfile = cf_get_option ("LogFile", LOGFILE)) != NULL)
338 DBG_STARTFILE (logfile, "Debug file opened.");
339 #endif
341 /*
342 * Read options from the config file, the environment and the command
343 * line (in that order, with later options overwriting previous ones in
344 * general).
345 * Also, this will automatically load modules.
346 */
347 if (cf_read (configfile))
348 {
349 fprintf (stderr, "Error: Reading the config file failed!\n"
350 "Read the syslog for details.\n");
351 return (1);
352 }
354 /*
355 * Change directory. We do this _after_ reading the config and loading
356 * modules to relative paths work as expected.
357 */
358 if ((datadir = cf_get_option ("DataDir", PKGLOCALSTATEDIR)) == NULL)
359 {
360 fprintf (stderr, "Don't have a datadir to use. This should not happen. Ever.");
361 return (1);
362 }
363 if (change_basedir (datadir))
364 {
365 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", datadir);
366 return (1);
367 }
369 #if COLLECT_DAEMON
370 /*
371 * fork off child
372 */
373 sigChldAction.sa_handler = SIG_IGN;
374 sigaction (SIGCHLD, &sigChldAction, NULL);
376 if ((pidfile == NULL)
377 && ((pidfile = cf_get_option ("PIDFile", PIDFILE)) == NULL))
378 {
379 fprintf (stderr, "Cannot obtain pidfile. This shoud not happen. Ever.");
380 return (1);
381 }
383 if (daemonize)
384 {
385 if ((pid = fork ()) == -1)
386 {
387 /* error */
388 fprintf (stderr, "fork: %s", strerror (errno));
389 return (1);
390 }
391 else if (pid != 0)
392 {
393 /* parent */
394 /* printf ("Running (PID %i)\n", pid); */
395 return (0);
396 }
398 /* Detach from session */
399 setsid ();
401 /* Write pidfile */
402 if (pidfile_create (pidfile))
403 exit (2);
405 /* close standard descriptors */
406 close (2);
407 close (1);
408 close (0);
410 if (open ("/dev/null", O_RDWR) != 0)
411 {
412 syslog (LOG_ERR, "Error: Could not connect `STDIN' to `/dev/null'");
413 return (1);
414 }
415 if (dup (0) != 1)
416 {
417 syslog (LOG_ERR, "Error: Could not connect `STDOUT' to `/dev/null'");
418 return (1);
419 }
420 if (dup (0) != 2)
421 {
422 syslog (LOG_ERR, "Error: Could not connect `STDERR' to `/dev/null'");
423 return (1);
424 }
425 } /* if (daemonize) */
426 #endif /* COLLECT_DAEMON */
428 /*
429 * install signal handlers
430 */
431 sigIntAction.sa_handler = sigIntHandler;
432 sigaction (SIGINT, &sigIntAction, NULL);
434 sigTermAction.sa_handler = sigTermHandler;
435 sigaction (SIGTERM, &sigTermAction, NULL);
437 /*
438 * run the actual loops
439 */
440 #if HAVE_LIBRRD
441 if (operating_mode == MODE_SERVER)
442 start_server ();
443 else /* if (operating_mode == MODE_CLIENT || operating_mode == MODE_LOCAL || operating_mode == MODE_LOG) */
444 #endif
445 start_client ();
447 plugin_shutdown_all ();
449 #if COLLECT_DEBUG
450 if (logfile != NULL)
451 DBG_STOPFILE("debug file closed.");
452 #endif
454 /* close syslog */
455 syslog (LOG_INFO, "Exiting normally");
456 closelog ();
458 #if COLLECT_DAEMON
459 if (daemonize)
460 pidfile_remove (pidfile);
461 #endif /* COLLECT_DAEMON */
463 return (0);
464 } /* int main (int argc, char **argv) */