mmd: rename dbt_num to selector_num
[paraslash.git] / server.c
1 /*
2 * Copyright (C) 1997-2006 Andre Noll <maan@systemlinux.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
17 */
18
19 /** \file server.c Paraslash's main server */
20
21
22 /** \mainpage Paraslash API Reference
23 *
24 * Good starting points for reading are probably \ref audio_file_selector,
25 * \ref sender, \ref receiver, \ref receiver_node, \ref filter, \ref
26 * filter_node.
27 *
28 */
29
30
31
32 #include "server.cmdline.h"
33 #include "db.h"
34 #include "server.h"
35 #include "afs.h"
36 #include "config.h"
37 #include "close_on_fork.h"
38 #include "send.h"
39 #include "error.h"
40 #include "net.h"
41 #include "daemon.h"
42 #include "string.h"
43 #include "ipc.h"
44
45 /** define the array of error lists needed by para_server */
46 INIT_SERVER_ERRLISTS;
47
48 /** shut down non-authorized connections after that many seconds */
49 #define ALARM_TIMEOUT 10
50
51 /* these are exported to afs.c. command.c and to all selectors */
52 struct misc_meta_data *mmd;
53 /** the configuration of para_server
54 *
55 * It also contains the options for all audio file selectors and all supported
56 * senders.
57 */
58 struct gengetopt_args_info conf;
59 char *user_list = NULL;
60 extern void http_send_init(struct sender *);
61 extern void ortp_send_init(struct sender *);
62 extern struct audio_format afl[];
63
64 /** the list of supported audio file selectors */
65 struct audio_file_selector dblist[] = {
66 {
67 .name = "random",
68 .init = random_selector_init,
69 .update_audio_file = NULL,
70 },
71 {
72 .name = "playlist",
73 .init = playlist_selector_init,
74 .update_audio_file = NULL,
75 .pre_select = NULL,
76 .post_select = NULL,
77 },
78 #ifdef HAVE_MYSQL
79 {
80 .name = "mysql",
81 .init = mysql_selector_init,
82 .update_audio_file = NULL,
83 .pre_select = NULL,
84 .post_select = NULL,
85 },
86 #endif
87 {
88 .name = NULL,
89 }
90 };
91
92 /** the list of supported senders */
93 struct sender senders[] = {
94 {
95 .name = "http",
96 .init = http_send_init,
97 },
98 #ifdef HAVE_ORTP
99 {
100 .name = "ortp",
101 .init = ortp_send_init,
102 },
103 #endif
104 {
105 .name = NULL,
106 }
107 };
108
109
110 /* global variables for server-internal use */
111 static FILE *logfile;
112 static int mmd_mutex, mmd_shm_id;
113 static int signal_pipe;
114
115 /**
116 * para_server's log function
117 *
118 * \param ll the log level
119 * \param fmt the format string describing the log message
120 */
121 void para_log(int ll, char* fmt,...)
122 {
123 va_list argp;
124 FILE *outfd;
125 struct tm *tm;
126 time_t t1;
127 char str[MAXLINE] = "";
128 pid_t mypid;
129
130 if (ll < conf.loglevel_arg)
131 return;
132 if (!logfile) {
133 if (ll < WARNING)
134 outfd = stdout;
135 else
136 outfd = stderr;
137 } else
138 outfd = logfile;
139 if (conf.daemon_given && !logfile)
140 return;
141 time(&t1);
142 tm = localtime(&t1);
143 strftime(str, MAXLINE, "%b %d %H:%M:%S", tm);
144 fprintf(outfd, "%s ", str);
145 if (conf.loglevel_arg <= INFO)
146 fprintf(outfd, "%i: ", ll);
147 mypid = getpid();
148 if (conf.loglevel_arg <= INFO)
149 fprintf(outfd, "(%d) ", mypid);
150 va_start(argp, fmt);
151 vfprintf(outfd, fmt, argp);
152 va_end(argp);
153 }
154
155 /*
156 * setup shared memory area and get mutex for locking
157 */
158 static void shm_init(void)
159 {
160 void *shm;
161 int ret = shm_new(sizeof(struct misc_meta_data));
162
163 if (ret < 0)
164 goto err_out;
165
166 ret = shm_attach(ret, ATTACH_RW, &shm);
167 if (ret < 0)
168 goto err_out;
169 mmd = shm;
170 mmd_shm_id = ret;
171
172 ret = mutex_new();
173 if (ret < 0)
174 goto err_out;
175 mmd_mutex = ret;
176
177 mmd->selector_num = 0;
178 mmd->num_played = 0;
179 mmd->num_commands = 0;
180 mmd->events = 0;
181 mmd->num_connects = 0;
182 mmd->active_connections = 0;
183 strcpy(mmd->filename, "(none)");
184 mmd->audio_format = -1;
185 mmd->afs_status_flags = AFS_NEXT;
186 mmd->new_afs_status_flags = AFS_NEXT;
187 mmd->sender_cmd_data.cmd_num = -1;
188 return;
189 err_out:
190 PARA_EMERG_LOG("%s", PARA_STRERROR(-ret));
191 exit(EXIT_FAILURE);
192 }
193
194 /**
195 * lock the shared memory area containing the mmd struct
196 *
197 * \sa semop(2), struct misc_meta_data
198 */
199 void mmd_lock(void)
200 {
201 mutex_lock(mmd_mutex);
202 }
203
204 /**
205 * unlock the shared memory area containing the mmd struct
206 *
207 * \sa semop(2), struct misc_meta_data
208 */
209
210 void mmd_unlock(void)
211 {
212 mutex_unlock(mmd_mutex);
213 }
214
215 static void parse_config(int override)
216 {
217 char *home = para_homedir();
218 struct stat statbuf;
219 int ret;
220 char *cf;
221
222 if (conf.config_file_given)
223 cf = conf.config_file_arg;
224 else
225 cf = make_message("%s/.paraslash/server.conf", home);
226 free(user_list);
227 if (!conf.user_list_given)
228 user_list = make_message("%s/.paraslash/server.users", home);
229 else
230 user_list = para_strdup(conf.user_list_arg);
231 ret = stat(cf, &statbuf);
232 if (ret && conf.config_file_given) {
233 ret = -1;
234 PARA_EMERG_LOG("can not stat config file %s\n", cf);
235 goto out;
236 }
237 if (!ret) {
238 int tmp = conf.daemon_given;
239 cmdline_parser_configfile(cf, &conf, override, 0, 0);
240 conf.daemon_given = tmp;
241 }
242 /* logfile */
243 if (!conf.logfile_given && conf.daemon_given) {
244 ret = -1;
245 PARA_EMERG_LOG("%s", "daemon, but no log file\n");
246 goto out;
247 }
248 if (conf.logfile_given)
249 logfile = open_log(conf.logfile_arg);
250 ret = 1;
251 out:
252 free(cf);
253 free(home);
254 if (ret > 0)
255 return;
256 free(user_list);
257 user_list = NULL;
258 exit(EXIT_FAILURE);
259 }
260
261 static void setup_signal_handling(void)
262 {
263 int ret = 0;
264
265 signal_pipe = para_signal_init();
266 // fcntl(signal_pipe, F_SETFL, O_NONBLOCK);
267 PARA_NOTICE_LOG("%s", "setting up signal handlers\n");
268 ret += para_install_sighandler(SIGINT);
269 ret += para_install_sighandler(SIGTERM);
270 ret += para_install_sighandler(SIGHUP);
271 ret += para_install_sighandler(SIGCHLD);
272 ret += para_install_sighandler(SIGUSR1);
273 signal(SIGPIPE, SIG_IGN);
274 if (ret != 5) {
275 PARA_EMERG_LOG("%s", "could not install signal handlers\n");
276 exit(EXIT_FAILURE);
277 }
278 }
279
280 static void init_selector(void)
281 {
282 int i, ret;
283
284 mmd->dbt_change = -1; /* no change nec., set to new dbt num by com_cdt */
285 if (!conf.selector_given)
286 goto random;
287 for (i = 0; dblist[i].name; i++) {
288 if (strcmp(dblist[i].name, conf.selector_arg))
289 continue;
290 PARA_NOTICE_LOG("initializing %s audio file selector\n",
291 dblist[i].name);
292 ret = dblist[i].init(&dblist[i]);
293 if (ret < 0) {
294 PARA_WARNING_LOG("%s", PARA_STRERROR(-ret));
295 break;
296 }
297 mmd->selector_num = i;
298 return;
299 }
300 PARA_WARNING_LOG("%s", "falling back to the random selector\n");
301 random:
302 mmd->selector_num = 0;
303 dblist[0].init(&dblist[0]); /* always successful */
304 }
305
306 static unsigned init_network(void)
307 {
308 int sockfd = init_tcp_socket(conf.port_arg);
309
310 if (sockfd < 0)
311 exit(EXIT_FAILURE);
312 return sockfd;
313 }
314
315 static void init_random_seed(void)
316 {
317 int fd, ret = -1, len = sizeof(unsigned int);
318 unsigned int seed;
319
320 fd = open("/dev/random", O_RDONLY);
321 if (fd < 0)
322 goto out;
323 ret = -2;
324 if (read(fd, &seed, len) != len)
325 goto out;
326 srandom(seed);
327 ret = 1;
328 out:
329 if (fd >= 0)
330 close(fd);
331 if (ret > 0)
332 return;
333 PARA_EMERG_LOG("can not seed pseudo random generator (ret = %d)\n",
334 ret);
335 exit(EXIT_FAILURE);
336 }
337
338 static unsigned do_inits(int argc, char **argv)
339 {
340 /* connector's address information */
341 int sockfd;
342
343 init_random_seed();
344 /* parse command line options */
345 cmdline_parser(argc, argv, &conf);
346 para_drop_privileges(conf.user_arg);
347 /* parse config file, open log and set defaults */
348 parse_config(0);
349 log_welcome("para_server", conf.loglevel_arg);
350 shm_init(); /* init mmd struct */
351 server_uptime(UPTIME_SET); /* reset server uptime */
352 /* become daemon */
353 if (conf.daemon_given)
354 daemon_init();
355 init_selector();
356 PARA_NOTICE_LOG("%s", "initializing audio file sender\n");
357 /* audio file sender */
358 afs_init();
359 mmd->server_pid = getpid();
360 setup_signal_handling();
361 mmd_lock();
362 /* init network socket */
363 PARA_NOTICE_LOG("%s", "initializing tcp command socket\n");
364 sockfd = init_network();
365 if (conf.autoplay_given) {
366 mmd->afs_status_flags |= AFS_PLAYING;
367 mmd->new_afs_status_flags |= AFS_PLAYING;
368 }
369 PARA_NOTICE_LOG("%s", "init complete\n");
370 return sockfd;
371 }
372
373 static void handle_dbt_change(void)
374 {
375 int ret, old = mmd->selector_num, new = mmd->dbt_change;
376
377 dblist[old].shutdown();
378 ret = dblist[new].init(&dblist[new]);
379 mmd->dbt_change = -1; /* reset */
380 if (ret >= 0) {
381 mmd->selector_num = new;
382 return;
383 }
384 /* init failed */
385 PARA_ERROR_LOG("%s -- switching to the random selector\n", PARA_STRERROR(-ret));
386 dblist[0].init(&dblist[0]);
387 mmd->selector_num = 0;
388 }
389
390 /*
391 * called when server gets SIGHUP or when client invokes hup command.
392 */
393 static void handle_sighup(void)
394 {
395 PARA_NOTICE_LOG("%s", "SIGHUP\n");
396 close_log(logfile); /* gets reopened if necessary by parse_config */
397 logfile = NULL;
398 parse_config(1); /* reopens log */
399 mmd->dbt_change = mmd->selector_num; /* do not change selector */
400 handle_dbt_change(); /* reload selector */
401 }
402
403 static void status_refresh(void)
404 {
405 static int prev_uptime = -1, prev_events = -1;
406 int uptime = server_uptime(UPTIME_GET), ret = 1;
407
408 if (prev_events != mmd->events)
409 goto out;
410 if (mmd->new_afs_status_flags != mmd->afs_status_flags)
411 goto out;
412 if (uptime / 60 != prev_uptime / 60)
413 goto out;
414 ret = 0;
415 out:
416 prev_uptime = uptime;
417 prev_events = mmd->events;
418 mmd->afs_status_flags = mmd->new_afs_status_flags;
419 if (ret) {
420 PARA_DEBUG_LOG("%d events, forcing status update, af = %d\n",
421 mmd->events, mmd->audio_format);
422 killpg(0, SIGUSR1);
423 }
424 }
425
426 /*
427 * MAIN
428 */
429 int main(int argc, char *argv[])
430 {
431 /* listen on sock_fd, new connection on new_fd */
432 int sockfd, new_fd;
433 struct sockaddr_in their_addr;
434 int err, i, max_fileno, ret;
435 pid_t chld_pid;
436 fd_set rfds, wfds;
437 struct timeval *timeout;
438
439 valid_fd_012();
440 sockfd = do_inits(argc, argv);
441 repeat:
442 /* check socket and signal pipe in any case */
443 FD_ZERO(&rfds);
444 FD_ZERO(&wfds);
445 FD_SET(sockfd, &rfds);
446 max_fileno = sockfd;
447 FD_SET(signal_pipe, &rfds);
448 max_fileno = MAX(max_fileno, signal_pipe);
449
450 timeout = afs_preselect();
451 status_refresh();
452 for (i = 0; senders[i].name; i++) {
453 if (senders[i].status != SENDER_ON)
454 continue;
455 if (!senders[i].pre_select)
456 continue;
457 senders[i].pre_select(mmd->audio_format >= 0?
458 &afl[mmd->audio_format] : NULL,
459 &max_fileno,
460 &rfds, &wfds);
461 }
462 if (dblist[mmd->selector_num].pre_select) {
463 ret = dblist[mmd->selector_num].pre_select(&rfds, &wfds);
464 max_fileno = MAX(max_fileno, ret);
465 }
466 mmd_unlock();
467 // PARA_DEBUG_LOG("%s: select (max = %i)\n", __func__, max_fileno);
468 ret = select(max_fileno + 1, &rfds, &wfds, NULL, timeout);
469 err = errno;
470 //PARA_DEBUG_LOG("%s: select returned %i\n", __func__, ret);
471 mmd_lock();
472 if (mmd->dbt_change >= 0)
473 handle_dbt_change();
474 if (dblist[mmd->selector_num].post_select)
475 dblist[mmd->selector_num].post_select(&rfds, &wfds);
476 if (ret < 0 && err == EINTR)
477 goto repeat;
478 if (ret < 0) {
479 PARA_CRIT_LOG("select error (%s)\n", strerror(err));
480 goto repeat;
481 }
482 for (i = 0; senders[i].name; i++) {
483 if (senders[i].status != SENDER_ON)
484 continue;
485 if (!senders[i].post_select)
486 continue;
487 senders[i].post_select(mmd->audio_format >= 0?
488 &afl[mmd->audio_format] : NULL,
489 &rfds, &wfds);
490 }
491 if (!ret) {
492 afs_send_chunk();
493 status_refresh();
494 }
495 if (FD_ISSET(signal_pipe, &rfds)) {
496 int sig;
497 sig = para_next_signal();
498 switch (sig) {
499 case SIGHUP:
500 handle_sighup();
501 break;
502 case SIGCHLD:
503 para_reap_children();
504 break;
505 /* die on sigint/sigterm. Kill all children too. */
506 case SIGINT:
507 case SIGTERM:
508 PARA_EMERG_LOG("terminating on signal %d\n", sig);
509 kill(0, SIGTERM);
510 dblist[mmd->selector_num].shutdown();
511 mutex_destroy(mmd_mutex);
512 shm_detach(mmd);
513 shm_destroy(mmd_shm_id);
514 exit(EXIT_FAILURE);
515 }
516 }
517 if (mmd->sender_cmd_data.cmd_num >= 0) {
518 int num = mmd->sender_cmd_data.cmd_num,
519 s = mmd->sender_cmd_data.sender_num;
520
521 if (senders[s].client_cmds[num])
522 senders[s].client_cmds[num](&mmd->sender_cmd_data);
523 mmd->sender_cmd_data.cmd_num = -1;
524 }
525 if (!FD_ISSET(sockfd, &rfds))
526 goto repeat;
527
528 new_fd = para_accept(sockfd, &their_addr, sizeof(struct sockaddr_in));
529 if (new_fd < 0)
530 goto repeat;
531 PARA_INFO_LOG("got connection from %s, forking\n",
532 inet_ntoa(their_addr.sin_addr));
533 mmd->num_connects++;
534 mmd->active_connections++;
535 random();
536 chld_pid = fork();
537 if (chld_pid < 0) {
538 PARA_CRIT_LOG("%s", "fork failed\n");
539 goto repeat;
540 }
541 if (chld_pid) {
542 close(new_fd);
543 /* parent keeps accepting connections */
544 goto repeat;
545 }
546 alarm(ALARM_TIMEOUT);
547 close_listed_fds();
548 close(sockfd); /* child doesn't need the listener */
549 /*
550 * put info on who we are serving into argv[0] to make
551 * client ip visible in top/ps
552 */
553 for (i = argc - 1; i >= 0; i--)
554 memset(argv[i], 0, strlen(argv[i]));
555 sprintf(argv[0], "para_server (serving %s)",
556 inet_ntoa(their_addr.sin_addr));
557 return handle_connect(new_fd, &their_addr);
558 }