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 };
59 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
61 static int loop = 0;
63 /* socket configuration */
64 static int sock_fd = -1;
65 static char *sock_file = NULL;
66 static char *sock_group = NULL;
67 static int sock_perms = S_IRWXU | S_IRWXG;
69 static pthread_t listen_thread = (pthread_t) 0;
71 /*
72 * Functions
73 */
74 static int us_open_socket (void)
75 {
76 struct sockaddr_un sa;
77 int status;
79 sock_fd = socket (PF_UNIX, SOCK_STREAM, 0);
80 if (sock_fd < 0)
81 {
82 char errbuf[1024];
83 ERROR ("unixsock plugin: socket failed: %s",
84 sstrerror (errno, errbuf, sizeof (errbuf)));
85 return (-1);
86 }
88 memset (&sa, '\0', sizeof (sa));
89 sa.sun_family = AF_UNIX;
90 sstrncpy (sa.sun_path, (sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
91 sizeof (sa.sun_path));
92 /* unlink (sa.sun_path); */
94 DEBUG ("unixsock plugin: socket path = %s", sa.sun_path);
96 status = bind (sock_fd, (struct sockaddr *) &sa, sizeof (sa));
97 if (status != 0)
98 {
99 char errbuf[1024];
100 sstrerror (errno, errbuf, sizeof (errbuf));
101 ERROR ("unixsock plugin: bind failed: %s", errbuf);
102 close (sock_fd);
103 sock_fd = -1;
104 return (-1);
105 }
107 chmod (sa.sun_path, sock_perms);
109 status = listen (sock_fd, 8);
110 if (status != 0)
111 {
112 char errbuf[1024];
113 ERROR ("unixsock plugin: listen failed: %s",
114 sstrerror (errno, errbuf, sizeof (errbuf)));
115 close (sock_fd);
116 sock_fd = -1;
117 return (-1);
118 }
120 do
121 {
122 char *grpname;
123 struct group *g;
124 struct group sg;
125 char grbuf[2048];
127 grpname = (sock_group != NULL) ? sock_group : COLLECTD_GRP_NAME;
128 g = NULL;
130 status = getgrnam_r (grpname, &sg, grbuf, sizeof (grbuf), &g);
131 if (status != 0)
132 {
133 char errbuf[1024];
134 WARNING ("unixsock plugin: getgrnam_r (%s) failed: %s", grpname,
135 sstrerror (errno, errbuf, sizeof (errbuf)));
136 break;
137 }
138 if (g == NULL)
139 {
140 WARNING ("unixsock plugin: No such group: `%s'",
141 grpname);
142 break;
143 }
145 if (chown ((sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
146 (uid_t) -1, g->gr_gid) != 0)
147 {
148 char errbuf[1024];
149 WARNING ("unixsock plugin: chown (%s, -1, %i) failed: %s",
150 (sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
151 (int) g->gr_gid,
152 sstrerror (errno, errbuf, sizeof (errbuf)));
153 }
154 } while (0);
156 return (0);
157 } /* int us_open_socket */
159 static void *us_handle_client (void *arg)
160 {
161 int fdin;
162 int fdout;
163 FILE *fhin, *fhout;
165 fdin = *((int *) arg);
166 free (arg);
167 arg = NULL;
169 DEBUG ("unixsock plugin: us_handle_client: Reading from fd #%i", fdin);
171 fdout = dup (fdin);
172 if (fdout < 0)
173 {
174 char errbuf[1024];
175 ERROR ("unixsock plugin: dup failed: %s",
176 sstrerror (errno, errbuf, sizeof (errbuf)));
177 close (fdin);
178 pthread_exit ((void *) 1);
179 }
181 fhin = fdopen (fdin, "r");
182 if (fhin == NULL)
183 {
184 char errbuf[1024];
185 ERROR ("unixsock plugin: fdopen failed: %s",
186 sstrerror (errno, errbuf, sizeof (errbuf)));
187 close (fdin);
188 close (fdout);
189 pthread_exit ((void *) 1);
190 }
192 fhout = fdopen (fdout, "w");
193 if (fhout == NULL)
194 {
195 char errbuf[1024];
196 ERROR ("unixsock plugin: fdopen failed: %s",
197 sstrerror (errno, errbuf, sizeof (errbuf)));
198 fclose (fhin); /* this closes fdin as well */
199 close (fdout);
200 pthread_exit ((void *) 1);
201 }
203 /* change output buffer to line buffered mode */
204 if (setvbuf (fhout, NULL, _IOLBF, 0) != 0)
205 {
206 char errbuf[1024];
207 ERROR ("unixsock plugin: setvbuf failed: %s",
208 sstrerror (errno, errbuf, sizeof (errbuf)));
209 fclose (fhin);
210 fclose (fhout);
211 pthread_exit ((void *) 1);
212 }
214 while (42)
215 {
216 char buffer[1024];
217 char buffer_copy[1024];
218 char *fields[128];
219 int fields_num;
220 int len;
222 errno = 0;
223 if (fgets (buffer, sizeof (buffer), fhin) == NULL)
224 {
225 if (errno != 0)
226 {
227 char errbuf[1024];
228 WARNING ("unixsock plugin: failed to read from socket #%i: %s",
229 fileno (fhin),
230 sstrerror (errno, errbuf, sizeof (errbuf)));
231 }
232 break;
233 }
235 len = strlen (buffer);
236 while ((len > 0)
237 && ((buffer[len - 1] == '\n') || (buffer[len - 1] == '\r')))
238 buffer[--len] = '\0';
240 if (len == 0)
241 continue;
243 sstrncpy (buffer_copy, buffer, sizeof (buffer_copy));
245 fields_num = strsplit (buffer_copy, fields,
246 sizeof (fields) / sizeof (fields[0]));
247 if (fields_num < 1)
248 {
249 fprintf (fhout, "-1 Internal error\n");
250 fclose (fhin);
251 fclose (fhout);
252 pthread_exit ((void *) 1);
253 }
255 if (strcasecmp (fields[0], "getval") == 0)
256 {
257 handle_getval (fhout, buffer);
258 }
259 else if (strcasecmp (fields[0], "getthreshold") == 0)
260 {
261 handle_getthreshold (fhout, buffer);
262 }
263 else if (strcasecmp (fields[0], "putval") == 0)
264 {
265 handle_putval (fhout, buffer);
266 }
267 else if (strcasecmp (fields[0], "listval") == 0)
268 {
269 handle_listval (fhout, buffer);
270 }
271 else if (strcasecmp (fields[0], "putnotif") == 0)
272 {
273 handle_putnotif (fhout, buffer);
274 }
275 else if (strcasecmp (fields[0], "flush") == 0)
276 {
277 handle_flush (fhout, buffer);
278 }
279 else
280 {
281 if (fprintf (fhout, "-1 Unknown command: %s\n", fields[0]) < 0)
282 {
283 char errbuf[1024];
284 WARNING ("unixsock plugin: failed to write to socket #%i: %s",
285 fileno (fhout),
286 sstrerror (errno, errbuf, sizeof (errbuf)));
287 break;
288 }
289 }
290 } /* while (fgets) */
292 DEBUG ("unixsock plugin: us_handle_client: Exiting..");
293 fclose (fhin);
294 fclose (fhout);
296 pthread_exit ((void *) 0);
297 return ((void *) 0);
298 } /* void *us_handle_client */
300 static void *us_server_thread (void __attribute__((unused)) *arg)
301 {
302 int status;
303 int *remote_fd;
304 pthread_t th;
305 pthread_attr_t th_attr;
307 if (us_open_socket () != 0)
308 pthread_exit ((void *) 1);
310 while (loop != 0)
311 {
312 DEBUG ("unixsock plugin: Calling accept..");
313 status = accept (sock_fd, NULL, NULL);
314 if (status < 0)
315 {
316 char errbuf[1024];
318 if (errno == EINTR)
319 continue;
321 ERROR ("unixsock plugin: accept failed: %s",
322 sstrerror (errno, errbuf, sizeof (errbuf)));
323 close (sock_fd);
324 sock_fd = -1;
325 pthread_exit ((void *) 1);
326 }
328 remote_fd = (int *) malloc (sizeof (int));
329 if (remote_fd == NULL)
330 {
331 char errbuf[1024];
332 WARNING ("unixsock plugin: malloc failed: %s",
333 sstrerror (errno, errbuf, sizeof (errbuf)));
334 close (status);
335 continue;
336 }
337 *remote_fd = status;
339 DEBUG ("Spawning child to handle connection on fd #%i", *remote_fd);
341 pthread_attr_init (&th_attr);
342 pthread_attr_setdetachstate (&th_attr, PTHREAD_CREATE_DETACHED);
344 status = pthread_create (&th, &th_attr, us_handle_client, (void *) remote_fd);
345 if (status != 0)
346 {
347 char errbuf[1024];
348 WARNING ("unixsock plugin: pthread_create failed: %s",
349 sstrerror (errno, errbuf, sizeof (errbuf)));
350 close (*remote_fd);
351 free (remote_fd);
352 continue;
353 }
354 } /* while (loop) */
356 close (sock_fd);
357 sock_fd = -1;
359 status = unlink ((sock_file != NULL) ? sock_file : US_DEFAULT_PATH);
360 if (status != 0)
361 {
362 char errbuf[1024];
363 NOTICE ("unixsock plugin: unlink (%s) failed: %s",
364 (sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
365 sstrerror (errno, errbuf, sizeof (errbuf)));
366 }
368 return ((void *) 0);
369 } /* void *us_server_thread */
371 static int us_config (const char *key, const char *val)
372 {
373 if (strcasecmp (key, "SocketFile") == 0)
374 {
375 char *new_sock_file = strdup (val);
376 if (new_sock_file == NULL)
377 return (1);
379 sfree (sock_file);
380 sock_file = new_sock_file;
381 }
382 else if (strcasecmp (key, "SocketGroup") == 0)
383 {
384 char *new_sock_group = strdup (val);
385 if (new_sock_group == NULL)
386 return (1);
388 sfree (sock_group);
389 sock_group = new_sock_group;
390 }
391 else if (strcasecmp (key, "SocketPerms") == 0)
392 {
393 sock_perms = (int) strtol (val, NULL, 8);
394 }
395 else
396 {
397 return (-1);
398 }
400 return (0);
401 } /* int us_config */
403 static int us_init (void)
404 {
405 static int have_init = 0;
407 int status;
409 /* Initialize only once. */
410 if (have_init != 0)
411 return (0);
412 have_init = 1;
414 loop = 1;
416 status = pthread_create (&listen_thread, NULL, us_server_thread, NULL);
417 if (status != 0)
418 {
419 char errbuf[1024];
420 ERROR ("unixsock plugin: pthread_create failed: %s",
421 sstrerror (errno, errbuf, sizeof (errbuf)));
422 return (-1);
423 }
425 return (0);
426 } /* int us_init */
428 static int us_shutdown (void)
429 {
430 void *ret;
432 loop = 0;
434 if (listen_thread != (pthread_t) 0)
435 {
436 pthread_kill (listen_thread, SIGTERM);
437 pthread_join (listen_thread, &ret);
438 listen_thread = (pthread_t) 0;
439 }
441 plugin_unregister_init ("unixsock");
442 plugin_unregister_shutdown ("unixsock");
444 return (0);
445 } /* int us_shutdown */
447 void module_register (void)
448 {
449 plugin_register_config ("unixsock", us_config,
450 config_keys, config_keys_num);
451 plugin_register_init ("unixsock", us_init);
452 plugin_register_shutdown ("unixsock", us_shutdown);
453 } /* void module_register (void) */
455 /* vim: set sw=4 ts=4 sts=4 tw=78 : */