1 /**
2 * collectd - src/unixsock.c
3 * Copyright (C) 2007,2008 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; only version 2 of the License is applicable.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 *
18 * Author:
19 * Florian octo Forster <octo at verplant.org>
20 **/
22 #include "collectd.h"
23 #include "common.h"
24 #include "plugin.h"
25 #include "configfile.h"
27 #include "utils_cmd_flush.h"
28 #include "utils_cmd_getval.h"
29 #include "utils_cmd_getthreshold.h"
30 #include "utils_cmd_listval.h"
31 #include "utils_cmd_putval.h"
32 #include "utils_cmd_putnotif.h"
34 /* Folks without pthread will need to disable this plugin. */
35 #include <pthread.h>
37 #include <sys/socket.h>
38 #include <sys/stat.h>
39 #include <sys/un.h>
41 #include <grp.h>
43 #ifndef UNIX_PATH_MAX
44 # define UNIX_PATH_MAX sizeof (((struct sockaddr_un *)0)->sun_path)
45 #endif
47 #define US_DEFAULT_PATH LOCALSTATEDIR"/run/"PACKAGE_NAME"-unixsock"
49 /*
50 * Private variables
51 */
52 /* valid configuration file keys */
53 static const char *config_keys[] =
54 {
55 "SocketFile",
56 "SocketGroup",
57 "SocketPerms",
58 "DeleteSocket"
59 };
60 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
62 static int loop = 0;
64 /* socket configuration */
65 static int sock_fd = -1;
66 static char *sock_file = NULL;
67 static char *sock_group = NULL;
68 static int sock_perms = S_IRWXU | S_IRWXG;
69 static _Bool delete_socket = 0;
71 static pthread_t listen_thread = (pthread_t) 0;
73 /*
74 * Functions
75 */
76 static int us_open_socket (void)
77 {
78 struct sockaddr_un sa;
79 int status;
81 sock_fd = socket (PF_UNIX, SOCK_STREAM, 0);
82 if (sock_fd < 0)
83 {
84 char errbuf[1024];
85 ERROR ("unixsock plugin: socket failed: %s",
86 sstrerror (errno, errbuf, sizeof (errbuf)));
87 return (-1);
88 }
90 memset (&sa, '\0', sizeof (sa));
91 sa.sun_family = AF_UNIX;
92 sstrncpy (sa.sun_path, (sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
93 sizeof (sa.sun_path));
95 DEBUG ("unixsock plugin: socket path = %s", sa.sun_path);
97 if (delete_socket)
98 {
99 errno = 0;
100 status = unlink (sa.sun_path);
101 if ((status != 0) && (errno != ENOENT))
102 {
103 char errbuf[1024];
104 WARNING ("unixsock plugin: Deleting socket file \"%s\" failed: %s",
105 sa.sun_path,
106 sstrerror (errno, errbuf, sizeof (errbuf)));
107 }
108 else if (status == 0)
109 {
110 INFO ("unixsock plugin: Successfully deleted socket file \"%s\".",
111 sa.sun_path);
112 }
113 }
115 status = bind (sock_fd, (struct sockaddr *) &sa, sizeof (sa));
116 if (status != 0)
117 {
118 char errbuf[1024];
119 sstrerror (errno, errbuf, sizeof (errbuf));
120 ERROR ("unixsock plugin: bind failed: %s", errbuf);
121 close (sock_fd);
122 sock_fd = -1;
123 return (-1);
124 }
126 chmod (sa.sun_path, sock_perms);
128 status = listen (sock_fd, 8);
129 if (status != 0)
130 {
131 char errbuf[1024];
132 ERROR ("unixsock plugin: listen failed: %s",
133 sstrerror (errno, errbuf, sizeof (errbuf)));
134 close (sock_fd);
135 sock_fd = -1;
136 return (-1);
137 }
139 do
140 {
141 char *grpname;
142 struct group *g;
143 struct group sg;
144 char grbuf[2048];
146 grpname = (sock_group != NULL) ? sock_group : COLLECTD_GRP_NAME;
147 g = NULL;
149 status = getgrnam_r (grpname, &sg, grbuf, sizeof (grbuf), &g);
150 if (status != 0)
151 {
152 char errbuf[1024];
153 WARNING ("unixsock plugin: getgrnam_r (%s) failed: %s", grpname,
154 sstrerror (errno, errbuf, sizeof (errbuf)));
155 break;
156 }
157 if (g == NULL)
158 {
159 WARNING ("unixsock plugin: No such group: `%s'",
160 grpname);
161 break;
162 }
164 if (chown ((sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
165 (uid_t) -1, g->gr_gid) != 0)
166 {
167 char errbuf[1024];
168 WARNING ("unixsock plugin: chown (%s, -1, %i) failed: %s",
169 (sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
170 (int) g->gr_gid,
171 sstrerror (errno, errbuf, sizeof (errbuf)));
172 }
173 } while (0);
175 return (0);
176 } /* int us_open_socket */
178 static void *us_handle_client (void *arg)
179 {
180 int fdin;
181 int fdout;
182 FILE *fhin, *fhout;
184 fdin = *((int *) arg);
185 free (arg);
186 arg = NULL;
188 DEBUG ("unixsock plugin: us_handle_client: Reading from fd #%i", fdin);
190 fdout = dup (fdin);
191 if (fdout < 0)
192 {
193 char errbuf[1024];
194 ERROR ("unixsock plugin: dup failed: %s",
195 sstrerror (errno, errbuf, sizeof (errbuf)));
196 close (fdin);
197 pthread_exit ((void *) 1);
198 }
200 fhin = fdopen (fdin, "r");
201 if (fhin == NULL)
202 {
203 char errbuf[1024];
204 ERROR ("unixsock plugin: fdopen failed: %s",
205 sstrerror (errno, errbuf, sizeof (errbuf)));
206 close (fdin);
207 close (fdout);
208 pthread_exit ((void *) 1);
209 }
211 fhout = fdopen (fdout, "w");
212 if (fhout == NULL)
213 {
214 char errbuf[1024];
215 ERROR ("unixsock plugin: fdopen failed: %s",
216 sstrerror (errno, errbuf, sizeof (errbuf)));
217 fclose (fhin); /* this closes fdin as well */
218 close (fdout);
219 pthread_exit ((void *) 1);
220 }
222 /* change output buffer to line buffered mode */
223 if (setvbuf (fhout, NULL, _IOLBF, 0) != 0)
224 {
225 char errbuf[1024];
226 ERROR ("unixsock plugin: setvbuf failed: %s",
227 sstrerror (errno, errbuf, sizeof (errbuf)));
228 fclose (fhin);
229 fclose (fhout);
230 pthread_exit ((void *) 1);
231 }
233 while (42)
234 {
235 char buffer[1024];
236 char buffer_copy[1024];
237 char *fields[128];
238 int fields_num;
239 int len;
241 errno = 0;
242 if (fgets (buffer, sizeof (buffer), fhin) == NULL)
243 {
244 if (errno != 0)
245 {
246 char errbuf[1024];
247 WARNING ("unixsock plugin: failed to read from socket #%i: %s",
248 fileno (fhin),
249 sstrerror (errno, errbuf, sizeof (errbuf)));
250 }
251 break;
252 }
254 len = strlen (buffer);
255 while ((len > 0)
256 && ((buffer[len - 1] == '\n') || (buffer[len - 1] == '\r')))
257 buffer[--len] = '\0';
259 if (len == 0)
260 continue;
262 sstrncpy (buffer_copy, buffer, sizeof (buffer_copy));
264 fields_num = strsplit (buffer_copy, fields,
265 sizeof (fields) / sizeof (fields[0]));
266 if (fields_num < 1)
267 {
268 fprintf (fhout, "-1 Internal error\n");
269 fclose (fhin);
270 fclose (fhout);
271 pthread_exit ((void *) 1);
272 }
274 if (strcasecmp (fields[0], "getval") == 0)
275 {
276 handle_getval (fhout, buffer);
277 }
278 else if (strcasecmp (fields[0], "getthreshold") == 0)
279 {
280 handle_getthreshold (fhout, buffer);
281 }
282 else if (strcasecmp (fields[0], "putval") == 0)
283 {
284 handle_putval (fhout, buffer);
285 }
286 else if (strcasecmp (fields[0], "listval") == 0)
287 {
288 handle_listval (fhout, buffer);
289 }
290 else if (strcasecmp (fields[0], "putnotif") == 0)
291 {
292 handle_putnotif (fhout, buffer);
293 }
294 else if (strcasecmp (fields[0], "flush") == 0)
295 {
296 handle_flush (fhout, buffer);
297 }
298 else
299 {
300 if (fprintf (fhout, "-1 Unknown command: %s\n", fields[0]) < 0)
301 {
302 char errbuf[1024];
303 WARNING ("unixsock plugin: failed to write to socket #%i: %s",
304 fileno (fhout),
305 sstrerror (errno, errbuf, sizeof (errbuf)));
306 break;
307 }
308 }
309 } /* while (fgets) */
311 DEBUG ("unixsock plugin: us_handle_client: Exiting..");
312 fclose (fhin);
313 fclose (fhout);
315 pthread_exit ((void *) 0);
316 return ((void *) 0);
317 } /* void *us_handle_client */
319 static void *us_server_thread (void __attribute__((unused)) *arg)
320 {
321 int status;
322 int *remote_fd;
323 pthread_t th;
324 pthread_attr_t th_attr;
326 if (us_open_socket () != 0)
327 pthread_exit ((void *) 1);
329 while (loop != 0)
330 {
331 DEBUG ("unixsock plugin: Calling accept..");
332 status = accept (sock_fd, NULL, NULL);
333 if (status < 0)
334 {
335 char errbuf[1024];
337 if (errno == EINTR)
338 continue;
340 ERROR ("unixsock plugin: accept failed: %s",
341 sstrerror (errno, errbuf, sizeof (errbuf)));
342 close (sock_fd);
343 sock_fd = -1;
344 pthread_exit ((void *) 1);
345 }
347 remote_fd = (int *) malloc (sizeof (int));
348 if (remote_fd == NULL)
349 {
350 char errbuf[1024];
351 WARNING ("unixsock plugin: malloc failed: %s",
352 sstrerror (errno, errbuf, sizeof (errbuf)));
353 close (status);
354 continue;
355 }
356 *remote_fd = status;
358 DEBUG ("Spawning child to handle connection on fd #%i", *remote_fd);
360 pthread_attr_init (&th_attr);
361 pthread_attr_setdetachstate (&th_attr, PTHREAD_CREATE_DETACHED);
363 status = pthread_create (&th, &th_attr, us_handle_client, (void *) remote_fd);
364 if (status != 0)
365 {
366 char errbuf[1024];
367 WARNING ("unixsock plugin: pthread_create failed: %s",
368 sstrerror (errno, errbuf, sizeof (errbuf)));
369 close (*remote_fd);
370 free (remote_fd);
371 continue;
372 }
373 } /* while (loop) */
375 close (sock_fd);
376 sock_fd = -1;
378 status = unlink ((sock_file != NULL) ? sock_file : US_DEFAULT_PATH);
379 if (status != 0)
380 {
381 char errbuf[1024];
382 NOTICE ("unixsock plugin: unlink (%s) failed: %s",
383 (sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
384 sstrerror (errno, errbuf, sizeof (errbuf)));
385 }
387 return ((void *) 0);
388 } /* void *us_server_thread */
390 static int us_config (const char *key, const char *val)
391 {
392 if (strcasecmp (key, "SocketFile") == 0)
393 {
394 char *new_sock_file = strdup (val);
395 if (new_sock_file == NULL)
396 return (1);
398 sfree (sock_file);
399 sock_file = new_sock_file;
400 }
401 else if (strcasecmp (key, "SocketGroup") == 0)
402 {
403 char *new_sock_group = strdup (val);
404 if (new_sock_group == NULL)
405 return (1);
407 sfree (sock_group);
408 sock_group = new_sock_group;
409 }
410 else if (strcasecmp (key, "SocketPerms") == 0)
411 {
412 sock_perms = (int) strtol (val, NULL, 8);
413 }
414 else if (strcasecmp (key, "DeleteSocket") == 0)
415 {
416 if (IS_TRUE (val))
417 delete_socket = 1;
418 else
419 delete_socket = 0;
420 }
421 else
422 {
423 return (-1);
424 }
426 return (0);
427 } /* int us_config */
429 static int us_init (void)
430 {
431 static int have_init = 0;
433 int status;
435 /* Initialize only once. */
436 if (have_init != 0)
437 return (0);
438 have_init = 1;
440 loop = 1;
442 status = pthread_create (&listen_thread, NULL, us_server_thread, NULL);
443 if (status != 0)
444 {
445 char errbuf[1024];
446 ERROR ("unixsock plugin: pthread_create failed: %s",
447 sstrerror (errno, errbuf, sizeof (errbuf)));
448 return (-1);
449 }
451 return (0);
452 } /* int us_init */
454 static int us_shutdown (void)
455 {
456 void *ret;
458 loop = 0;
460 if (listen_thread != (pthread_t) 0)
461 {
462 pthread_kill (listen_thread, SIGTERM);
463 pthread_join (listen_thread, &ret);
464 listen_thread = (pthread_t) 0;
465 }
467 plugin_unregister_init ("unixsock");
468 plugin_unregister_shutdown ("unixsock");
470 return (0);
471 } /* int us_shutdown */
473 void module_register (void)
474 {
475 plugin_register_config ("unixsock", us_config,
476 config_keys, config_keys_num);
477 plugin_register_init ("unixsock", us_init);
478 plugin_register_shutdown ("unixsock", us_shutdown);
479 } /* void module_register (void) */
481 /* vim: set sw=4 ts=4 sts=4 tw=78 : */