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 fd;
162 FILE *fhin, *fhout;
164 fd = *((int *) arg);
165 free (arg);
166 arg = NULL;
168 DEBUG ("unixsock plugin: us_handle_client: Reading from fd #%i", fd);
170 fhin = fdopen (fd, "r");
171 if (fhin == NULL)
172 {
173 char errbuf[1024];
174 ERROR ("unixsock plugin: fdopen failed: %s",
175 sstrerror (errno, errbuf, sizeof (errbuf)));
176 close (fd);
177 pthread_exit ((void *) 1);
178 }
180 fhout = fdopen (fd, "w");
181 if (fhout == NULL)
182 {
183 char errbuf[1024];
184 ERROR ("unixsock plugin: fdopen failed: %s",
185 sstrerror (errno, errbuf, sizeof (errbuf)));
186 fclose (fhin); /* this closes fd as well */
187 pthread_exit ((void *) 1);
188 }
190 /* change output buffer to line buffered mode */
191 if (setvbuf (fhout, NULL, _IOLBF, 0) != 0)
192 {
193 char errbuf[1024];
194 ERROR ("unixsock plugin: setvbuf failed: %s",
195 sstrerror (errno, errbuf, sizeof (errbuf)));
196 fclose (fhin);
197 fclose (fhout);
198 pthread_exit ((void *) 1);
199 }
201 while (42)
202 {
203 char buffer[1024];
204 char buffer_copy[1024];
205 char *fields[128];
206 int fields_num;
207 int len;
209 errno = 0;
210 if (fgets (buffer, sizeof (buffer), fhin) == NULL)
211 {
212 if (errno != 0)
213 {
214 char errbuf[1024];
215 WARNING ("unixsock plugin: failed to read from socket #%i: %s",
216 fileno (fhin),
217 sstrerror (errno, errbuf, sizeof (errbuf)));
218 }
219 break;
220 }
222 len = strlen (buffer);
223 while ((len > 0)
224 && ((buffer[len - 1] == '\n') || (buffer[len - 1] == '\r')))
225 buffer[--len] = '\0';
227 if (len == 0)
228 continue;
230 sstrncpy (buffer_copy, buffer, sizeof (buffer_copy));
232 fields_num = strsplit (buffer_copy, fields,
233 sizeof (fields) / sizeof (fields[0]));
235 if (fields_num < 1)
236 {
237 close (fd);
238 break;
239 }
241 if (strcasecmp (fields[0], "getval") == 0)
242 {
243 handle_getval (fhout, buffer);
244 }
245 else if (strcasecmp (fields[0], "getthreshold") == 0)
246 {
247 handle_getthreshold (fhout, buffer);
248 }
249 else if (strcasecmp (fields[0], "putval") == 0)
250 {
251 handle_putval (fhout, buffer);
252 }
253 else if (strcasecmp (fields[0], "listval") == 0)
254 {
255 handle_listval (fhout, buffer);
256 }
257 else if (strcasecmp (fields[0], "putnotif") == 0)
258 {
259 handle_putnotif (fhout, buffer);
260 }
261 else if (strcasecmp (fields[0], "flush") == 0)
262 {
263 handle_flush (fhout, buffer);
264 }
265 else
266 {
267 if (fprintf (fhout, "-1 Unknown command: %s\n", fields[0]) < 0)
268 {
269 char errbuf[1024];
270 WARNING ("unixsock plugin: failed to write to socket #%i: %s",
271 fileno (fhout),
272 sstrerror (errno, errbuf, sizeof (errbuf)));
273 break;
274 }
275 }
276 } /* while (fgets) */
278 DEBUG ("unixsock plugin: us_handle_client: Exiting..");
279 fclose (fhin);
280 fclose (fhout);
282 pthread_exit ((void *) 0);
283 return ((void *) 0);
284 } /* void *us_handle_client */
286 static void *us_server_thread (void __attribute__((unused)) *arg)
287 {
288 int status;
289 int *remote_fd;
290 pthread_t th;
291 pthread_attr_t th_attr;
293 if (us_open_socket () != 0)
294 pthread_exit ((void *) 1);
296 while (loop != 0)
297 {
298 DEBUG ("unixsock plugin: Calling accept..");
299 status = accept (sock_fd, NULL, NULL);
300 if (status < 0)
301 {
302 char errbuf[1024];
304 if (errno == EINTR)
305 continue;
307 ERROR ("unixsock plugin: accept failed: %s",
308 sstrerror (errno, errbuf, sizeof (errbuf)));
309 close (sock_fd);
310 sock_fd = -1;
311 pthread_exit ((void *) 1);
312 }
314 remote_fd = (int *) malloc (sizeof (int));
315 if (remote_fd == NULL)
316 {
317 char errbuf[1024];
318 WARNING ("unixsock plugin: malloc failed: %s",
319 sstrerror (errno, errbuf, sizeof (errbuf)));
320 close (status);
321 continue;
322 }
323 *remote_fd = status;
325 DEBUG ("Spawning child to handle connection on fd #%i", *remote_fd);
327 pthread_attr_init (&th_attr);
328 pthread_attr_setdetachstate (&th_attr, PTHREAD_CREATE_DETACHED);
330 status = pthread_create (&th, &th_attr, us_handle_client, (void *) remote_fd);
331 if (status != 0)
332 {
333 char errbuf[1024];
334 WARNING ("unixsock plugin: pthread_create failed: %s",
335 sstrerror (errno, errbuf, sizeof (errbuf)));
336 close (*remote_fd);
337 free (remote_fd);
338 continue;
339 }
340 } /* while (loop) */
342 close (sock_fd);
343 sock_fd = -1;
345 status = unlink ((sock_file != NULL) ? sock_file : US_DEFAULT_PATH);
346 if (status != 0)
347 {
348 char errbuf[1024];
349 NOTICE ("unixsock plugin: unlink (%s) failed: %s",
350 (sock_file != NULL) ? sock_file : US_DEFAULT_PATH,
351 sstrerror (errno, errbuf, sizeof (errbuf)));
352 }
354 return ((void *) 0);
355 } /* void *us_server_thread */
357 static int us_config (const char *key, const char *val)
358 {
359 if (strcasecmp (key, "SocketFile") == 0)
360 {
361 char *new_sock_file = strdup (val);
362 if (new_sock_file == NULL)
363 return (1);
365 sfree (sock_file);
366 sock_file = new_sock_file;
367 }
368 else if (strcasecmp (key, "SocketGroup") == 0)
369 {
370 char *new_sock_group = strdup (val);
371 if (new_sock_group == NULL)
372 return (1);
374 sfree (sock_group);
375 sock_group = new_sock_group;
376 }
377 else if (strcasecmp (key, "SocketPerms") == 0)
378 {
379 sock_perms = (int) strtol (val, NULL, 8);
380 }
381 else
382 {
383 return (-1);
384 }
386 return (0);
387 } /* int us_config */
389 static int us_init (void)
390 {
391 static int have_init = 0;
393 int status;
395 /* Initialize only once. */
396 if (have_init != 0)
397 return (0);
398 have_init = 1;
400 loop = 1;
402 status = pthread_create (&listen_thread, NULL, us_server_thread, NULL);
403 if (status != 0)
404 {
405 char errbuf[1024];
406 ERROR ("unixsock plugin: pthread_create failed: %s",
407 sstrerror (errno, errbuf, sizeof (errbuf)));
408 return (-1);
409 }
411 return (0);
412 } /* int us_init */
414 static int us_shutdown (void)
415 {
416 void *ret;
418 loop = 0;
420 if (listen_thread != (pthread_t) 0)
421 {
422 pthread_kill (listen_thread, SIGTERM);
423 pthread_join (listen_thread, &ret);
424 listen_thread = (pthread_t) 0;
425 }
427 plugin_unregister_init ("unixsock");
428 plugin_unregister_shutdown ("unixsock");
430 return (0);
431 } /* int us_shutdown */
433 void module_register (void)
434 {
435 plugin_register_config ("unixsock", us_config,
436 config_keys, config_keys_num);
437 plugin_register_init ("unixsock", us_init);
438 plugin_register_shutdown ("unixsock", us_shutdown);
439 } /* void module_register (void) */
441 /* vim: set sw=4 ts=4 sts=4 tw=78 : */