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