make para_server use the new ipc subsystem
[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 dbtool, \ref sender,
25 * \ref receiver, \ref receiver_node, \ref filter, \ref filter_node.
26 *
27 */
28
29
30
31 #include "server.cmdline.h"
32 #include "db.h"
33 #include "server.h"
34 #include "afs.h"
35 #include "config.h"
36 #include "close_on_fork.h"
37 #include "send.h"
38 #include "error.h"
39 #include "net.h"
40 #include "daemon.h"
41 #include "string.h"
42 #include "ipc.h"
43
44 /** define the array of error lists needed by para_server */
45 INIT_SERVER_ERRLISTS;
46
47 /** shut down non-authorized connections after that many seconds */
48 #define ALARM_TIMEOUT 10
49
50 /* these are exported to afs/command/dbtool */
51 struct misc_meta_data *mmd;
52 /** the configuration of para_server
53 *
54 * It also contains the options for all database tools and all supported
55 * senders.
56 */
57 struct gengetopt_args_info conf;
58 char *user_list = NULL;
59 extern void http_send_init(struct sender *);
60 extern void ortp_send_init(struct sender *);
61 extern struct audio_format afl[];
62
63 /** the list of supported database tools */
64 struct dbtool dblist[] = {
65 {
66 .name = "random",
67 .init = random_dbtool_init,
68 .update_audio_file = NULL,
69 },
70 {
71 .name = "plm",
72 .init = plm_dbtool_init,
73 .update_audio_file = NULL,
74 .pre_select = NULL,
75 .post_select = NULL,
76 },
77 #ifdef HAVE_MYSQL
78 {
79 .name = "mysql",
80 .init = mysql_dbtool_init,
81 .update_audio_file = NULL,
82 .pre_select = NULL,
83 .post_select = NULL,
84 },
85 #endif
86 {
87 .name = NULL,
88 }
89 };
90
91 /** the list of supported senders */
92 struct sender senders[] = {
93 {
94 .name = "http",
95 .init = http_send_init,
96 },
97 #ifdef HAVE_ORTP
98 {
99 .name = "ortp",
100 .init = ortp_send_init,
101 },
102 #endif
103 {
104 .name = NULL,
105 }
106 };
107
108
109 /* global variables for server-internal use */
110 static FILE *logfile;
111 static int mmd_mutex, mmd_shm_id;
112 static int signal_pipe;
113
114 /**
115 * para_server's log function
116 *
117 * \param ll the log level
118 * \param fmt the format string describing the log message
119 */
120 void para_log(int ll, char* fmt,...)
121 {
122 va_list argp;
123 FILE *outfd;
124 struct tm *tm;
125 time_t t1;
126 char str[MAXLINE] = "";
127 pid_t mypid;
128
129 if (ll < conf.loglevel_arg)
130 return;
131 if (!logfile) {
132 if (ll < WARNING)
133 outfd = stdout;
134 else
135 outfd = stderr;
136 } else
137 outfd = logfile;
138 if (conf.daemon_given && !logfile)
139 return;
140 time(&t1);
141 tm = localtime(&t1);
142 strftime(str, MAXLINE, "%b %d %H:%M:%S", tm);
143 fprintf(outfd, "%s ", str);
144 if (conf.loglevel_arg <= INFO)
145 fprintf(outfd, "%i: ", ll);
146 mypid = getpid();
147 if (conf.loglevel_arg <= INFO)
148 fprintf(outfd, "(%d) ", mypid);
149 va_start(argp, fmt);
150 vfprintf(outfd, fmt, argp);
151 va_end(argp);
152 }
153
154 /*
155 * setup shared memory area and get mutex for locking
156 */
157 static void shm_init(void)
158 {
159 void *shm;
160 int ret = shm_new(sizeof(struct misc_meta_data));
161
162 if (ret < 0)
163 goto err_out;
164
165 ret = shm_attach(ret, ATTACH_RW, &shm);
166 if (ret < 0)
167 goto err_out;
168 mmd = shm;
169 mmd_shm_id = ret;
170
171 ret = mutex_new();
172 if (ret < 0)
173 goto err_out;
174 mmd_mutex = ret;
175
176 mmd->dbt_num = 0;
177 mmd->num_played = 0;
178 mmd->num_commands = 0;
179 mmd->events = 0;
180 mmd->num_connects = 0;
181 mmd->active_connections = 0;
182 strcpy(mmd->filename, "(none)");
183 mmd->audio_format = -1;
184 mmd->afs_status_flags = AFS_NEXT;
185 mmd->new_afs_status_flags = AFS_NEXT;
186 mmd->sender_cmd_data.cmd_num = -1;
187 return;
188 err_out:
189 PARA_EMERG_LOG("%s", PARA_STRERROR(-ret));
190 exit(EXIT_FAILURE);
191 }
192
193 /**
194 * lock the shared memory area containing the mmd struct
195 *
196 * \sa semop(2), struct misc_meta_data
197 */
198 void mmd_lock(void)
199 {
200 mutex_lock(mmd_mutex);
201 }
202
203 /**
204 * unlock the shared memory area containing the mmd struct
205 *
206 * \sa semop(2), struct misc_meta_data
207 */
208
209 void mmd_unlock(void)
210 {
211 mutex_unlock(mmd_mutex);
212 }
213
214 static void parse_config(int override)
215 {
216 char *home = para_homedir();
217 struct stat statbuf;
218 int ret;
219 char *cf;
220
221 if (conf.config_file_given)
222 cf = conf.config_file_arg;
223 else
224 cf = make_message("%s/.paraslash/server.conf", home);
225 free(user_list);
226 if (!conf.user_list_given)
227 user_list = make_message("%s/.paraslash/server.users", home);
228 else
229 user_list = para_strdup(conf.user_list_arg);
230 ret = stat(cf, &statbuf);
231 if (ret && conf.config_file_given) {
232 ret = -1;
233 PARA_EMERG_LOG("can not stat config file %s\n", cf);
234 goto out;
235 }
236 if (!ret) {
237 int tmp = conf.daemon_given;
238 cmdline_parser_configfile(cf, &conf, override, 0, 0);
239 conf.daemon_given = tmp;
240 }
241 /* logfile */
242 if (!conf.logfile_given && conf.daemon_given) {
243 ret = -1;
244 PARA_EMERG_LOG("%s", "daemon, but no log file\n");
245 goto out;
246 }
247 if (conf.logfile_given)
248 logfile = open_log(conf.logfile_arg);
249 ret = 1;
250 out:
251 free(cf);
252 free(home);
253 if (ret > 0)
254 return;
255 free(user_list);
256 user_list = NULL;
257 exit(EXIT_FAILURE);
258 }
259
260 static void setup_signal_handling(void)
261 {
262 int ret = 0;
263
264 signal_pipe = para_signal_init();
265 // fcntl(signal_pipe, F_SETFL, O_NONBLOCK);
266 PARA_NOTICE_LOG("%s", "setting up signal handlers\n");
267 ret += para_install_sighandler(SIGINT);
268 ret += para_install_sighandler(SIGTERM);
269 ret += para_install_sighandler(SIGHUP);
270 ret += para_install_sighandler(SIGCHLD);
271 ret += para_install_sighandler(SIGUSR1);
272 signal(SIGPIPE, SIG_IGN);
273 if (ret != 5) {
274 PARA_EMERG_LOG("%s", "could not install signal handlers\n");
275 exit(EXIT_FAILURE);
276 }
277 }
278
279 static void init_dbtool(void)
280 {
281 int i;
282
283 mmd->dbt_change = -1; /* no change nec., set to new dbt num by com_cdt */
284 if (!dblist[1].name)
285 goto random;
286 if (conf.dbtool_given) {
287 for (i = 0; dblist[i].name; i++) {
288 if (strcmp(dblist[i].name, conf.dbtool_arg))
289 continue;
290 PARA_NOTICE_LOG("initializing %s database tool\n",
291 dblist[i].name);
292 if (dblist[i].init(&dblist[i]) < 0) {
293 PARA_WARNING_LOG("init %s failed",
294 dblist[i].name);
295 goto random;
296 }
297 mmd->dbt_num = i;
298 return;
299 }
300 PARA_WARNING_LOG("%s", "no such dbtool, switching to random\n");
301 goto random;
302 }
303 /* use the first dbtool that works
304 * (assuming that random always works)
305 */
306 for (i = 1; dblist[i].name; i++) {
307 int ret = dblist[i].init(&dblist[i]);
308 if (ret >= 0) {
309 PARA_INFO_LOG("initialized %s\n", dblist[i].name);
310 mmd->dbt_num = i;
311 return;
312 }
313 PARA_CRIT_LOG("%s init failed: %s\n", dblist[i].name,
314 PARA_STRERROR(-ret));
315 }
316 random:
317 mmd->dbt_num = 0;
318 dblist[0].init(&dblist[0]); /* always successful */
319 }
320
321 static unsigned init_network(void)
322 {
323 int sockfd = init_tcp_socket(conf.port_arg);
324
325 if (sockfd < 0)
326 exit(EXIT_FAILURE);
327 return sockfd;
328 }
329
330 static void init_random_seed(void)
331 {
332 int fd, ret = -1, len = sizeof(unsigned int);
333 unsigned int seed;
334
335 fd = open("/dev/random", O_RDONLY);
336 if (fd < 0)
337 goto out;
338 ret = -2;
339 if (read(fd, &seed, len) != len)
340 goto out;
341 srandom(seed);
342 ret = 1;
343 out:
344 if (fd >= 0)
345 close(fd);
346 if (ret > 0)
347 return;
348 PARA_EMERG_LOG("can not seed pseudo random generator (ret = %d)\n",
349 ret);
350 exit(EXIT_FAILURE);
351 }
352
353 static unsigned do_inits(int argc, char **argv)
354 {
355 /* connector's address information */
356 int sockfd;
357
358 init_random_seed();
359 /* parse command line options */
360 cmdline_parser(argc, argv, &conf);
361 para_drop_privileges(conf.user_arg);
362 /* parse config file, open log and set defaults */
363 parse_config(0);
364 log_welcome("para_server", conf.loglevel_arg);
365 shm_init(); /* init mmd struct */
366 server_uptime(UPTIME_SET); /* reset server uptime */
367 /* become daemon */
368 if (conf.daemon_given)
369 daemon_init();
370 init_dbtool();
371 PARA_NOTICE_LOG("%s", "initializing audio file sender\n");
372 /* audio file sender */
373 afs_init();
374 mmd->server_pid = getpid();
375 setup_signal_handling();
376 mmd_lock();
377 /* init network socket */
378 PARA_NOTICE_LOG("%s", "initializing tcp command socket\n");
379 sockfd = init_network();
380 if (conf.autoplay_given) {
381 mmd->afs_status_flags |= AFS_PLAYING;
382 mmd->new_afs_status_flags |= AFS_PLAYING;
383 }
384 PARA_NOTICE_LOG("%s", "init complete\n");
385 return sockfd;
386 }
387
388 static void handle_dbt_change(void)
389 {
390 int ret, old = mmd->dbt_num, new = mmd->dbt_change;
391
392 dblist[old].shutdown();
393 ret = dblist[new].init(&dblist[new]);
394 mmd->dbt_change = -1; /* reset */
395 if (ret >= 0) {
396 mmd->dbt_num = new;
397 return;
398 }
399 /* init failed */
400 PARA_ERROR_LOG("%s -- switching to the random dbtool\n", PARA_STRERROR(-ret));
401 dblist[0].init(&dblist[0]);
402 mmd->dbt_num = 0;
403 }
404
405 /*
406 * called when server gets SIGHUP or when client invokes hup command.
407 */
408 static void handle_sighup(void)
409 {
410 PARA_NOTICE_LOG("%s", "SIGHUP\n");
411 close_log(logfile); /* gets reopened if necessary by parse_config */
412 logfile = NULL;
413 parse_config(1); /* reopens log */
414 mmd->dbt_change = mmd->dbt_num; /* do not change dbtool */
415 handle_dbt_change(); /* force reloading dbtool */
416 }
417
418 static void status_refresh(void)
419 {
420 static int prev_uptime = -1, prev_events = -1;
421 int uptime = server_uptime(UPTIME_GET), ret = 1;
422
423 if (prev_events != mmd->events)
424 goto out;
425 if (mmd->new_afs_status_flags != mmd->afs_status_flags)
426 goto out;
427 if (uptime / 60 != prev_uptime / 60)
428 goto out;
429 ret = 0;
430 out:
431 prev_uptime = uptime;
432 prev_events = mmd->events;
433 mmd->afs_status_flags = mmd->new_afs_status_flags;
434 if (ret) {
435 PARA_DEBUG_LOG("%d events, forcing status update, af = %d\n",
436 mmd->events, mmd->audio_format);
437 killpg(0, SIGUSR1);
438 }
439 }
440
441 /*
442 * MAIN
443 */
444 int main(int argc, char *argv[])
445 {
446 /* listen on sock_fd, new connection on new_fd */
447 int sockfd, new_fd;
448 struct sockaddr_in their_addr;
449 int err, i, max_fileno, ret;
450 pid_t chld_pid;
451 fd_set rfds, wfds;
452 struct timeval *timeout;
453
454 valid_fd_012();
455 sockfd = do_inits(argc, argv);
456 repeat:
457 /* check socket and signal pipe in any case */
458 FD_ZERO(&rfds);
459 FD_ZERO(&wfds);
460 FD_SET(sockfd, &rfds);
461 max_fileno = sockfd;
462 FD_SET(signal_pipe, &rfds);
463 max_fileno = MAX(max_fileno, signal_pipe);
464
465 timeout = afs_preselect();
466 status_refresh();
467 for (i = 0; senders[i].name; i++) {
468 if (senders[i].status != SENDER_ON)
469 continue;
470 if (!senders[i].pre_select)
471 continue;
472 senders[i].pre_select(mmd->audio_format >= 0?
473 &afl[mmd->audio_format] : NULL,
474 &max_fileno,
475 &rfds, &wfds);
476 }
477 if (dblist[mmd->dbt_num].pre_select) {
478 ret = dblist[mmd->dbt_num].pre_select(&rfds, &wfds);
479 max_fileno = MAX(max_fileno, ret);
480 }
481 mmd_unlock();
482 // PARA_DEBUG_LOG("%s: select (max = %i)\n", __func__, max_fileno);
483 ret = select(max_fileno + 1, &rfds, &wfds, NULL, timeout);
484 err = errno;
485 //PARA_DEBUG_LOG("%s: select returned %i\n", __func__, ret);
486 mmd_lock();
487 if (mmd->dbt_change >= 0)
488 handle_dbt_change();
489 if (dblist[mmd->dbt_num].post_select)
490 dblist[mmd->dbt_num].post_select(&rfds, &wfds);
491 if (ret < 0 && err == EINTR)
492 goto repeat;
493 if (ret < 0) {
494 PARA_CRIT_LOG("select error (%s)\n", strerror(err));
495 goto repeat;
496 }
497 for (i = 0; senders[i].name; i++) {
498 if (senders[i].status != SENDER_ON)
499 continue;
500 if (!senders[i].post_select)
501 continue;
502 senders[i].post_select(mmd->audio_format >= 0?
503 &afl[mmd->audio_format] : NULL,
504 &rfds, &wfds);
505 }
506 if (!ret) {
507 afs_send_chunk();
508 status_refresh();
509 }
510 if (FD_ISSET(signal_pipe, &rfds)) {
511 int sig;
512 sig = para_next_signal();
513 switch (sig) {
514 case SIGHUP:
515 handle_sighup();
516 break;
517 case SIGCHLD:
518 para_reap_children();
519 break;
520 /* die on sigint/sigterm. Kill all children too. */
521 case SIGINT:
522 case SIGTERM:
523 PARA_EMERG_LOG("terminating on signal %d\n", sig);
524 kill(0, SIGTERM);
525 dblist[mmd->dbt_num].shutdown();
526 mutex_destroy(mmd_mutex);
527 shm_detach(mmd);
528 shm_destroy(mmd_shm_id);
529 exit(EXIT_FAILURE);
530 }
531 }
532 if (mmd->sender_cmd_data.cmd_num >= 0) {
533 int num = mmd->sender_cmd_data.cmd_num,
534 s = mmd->sender_cmd_data.sender_num;
535
536 if (senders[s].client_cmds[num])
537 senders[s].client_cmds[num](&mmd->sender_cmd_data);
538 mmd->sender_cmd_data.cmd_num = -1;
539 }
540 if (!FD_ISSET(sockfd, &rfds))
541 goto repeat;
542
543 new_fd = para_accept(sockfd, &their_addr, sizeof(struct sockaddr_in));
544 if (new_fd < 0)
545 goto repeat;
546 PARA_INFO_LOG("got connection from %s, forking\n",
547 inet_ntoa(their_addr.sin_addr));
548 mmd->num_connects++;
549 mmd->active_connections++;
550 random();
551 chld_pid = fork();
552 if (chld_pid < 0) {
553 PARA_CRIT_LOG("%s", "fork failed\n");
554 goto repeat;
555 }
556 if (chld_pid) {
557 close(new_fd);
558 /* parent keeps accepting connections */
559 goto repeat;
560 }
561 alarm(ALARM_TIMEOUT);
562 close_listed_fds();
563 close(sockfd); /* child doesn't need the listener */
564 /*
565 * put info on who we are serving into argv[0] to make
566 * client ip visible in top/ps
567 */
568 for (i = argc - 1; i >= 0; i--)
569 memset(argv[i], 0, strlen(argv[i]));
570 sprintf(argv[0], "para_server (serving %s)",
571 inet_ntoa(their_addr.sin_addr));
572 return handle_connect(new_fd, &their_addr);
573 }