initial git commit
[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 <sys/mman.h> /* MAP_SHARED, PROT_READ, PROT_WRITE */
38 #include "send.h"
39 #include "error.h"
40 #include "net.h"
41 #include "daemon.h"
42 #include "string.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 = "dopey",
67 .init = dopey_dbtool_init,
68 .update_audio_file = NULL,
69 },
70 #ifdef HAVE_MYSQL
71 {
72 .name = "mysql",
73 .init = mysql_dbtool_init,
74 .update_audio_file = NULL,
75 },
76 #endif
77 {
78 .name = NULL,
79 }
80 };
81
82 /** the list of supported senders */
83 struct sender senders[] = {
84 {
85 .name = "http",
86 .init = http_send_init,
87 },
88 #ifdef HAVE_ORTP
89 {
90 .name = "ortp",
91 .init = ortp_send_init,
92 },
93 #endif
94 {
95 .name = NULL,
96 }
97 };
98
99
100 /* global variables for server-internal use */
101 static FILE *logfile;
102 static int mmd_semid;
103 static int signal_pipe;
104
105 /**
106 * para_server's log function
107 *
108 * \param ll the log level
109 * \param fmt the format string describing the log message
110 */
111 void para_log(int ll, char* fmt,...)
112 {
113 va_list argp;
114 FILE *outfd;
115 struct tm *tm;
116 time_t t1;
117 char str[MAXLINE] = "";
118 pid_t mypid;
119
120 if (ll < conf.loglevel_arg)
121 return;
122 if (!logfile) {
123 if (ll < WARNING)
124 outfd = stdout;
125 else
126 outfd = stderr;
127 } else
128 outfd = logfile;
129 if (conf.daemon_given && !logfile)
130 return;
131 time(&t1);
132 tm = localtime(&t1);
133 strftime(str, MAXLINE, "%b %d %H:%M:%S", tm);
134 fprintf(outfd, "%s ", str);
135 if (conf.loglevel_arg <= INFO)
136 fprintf(outfd, "%i: ", ll);
137 mypid = getpid();
138 if (conf.loglevel_arg <= INFO)
139 fprintf(outfd, "(%d) ", mypid);
140 va_start(argp, fmt);
141 vfprintf(outfd, fmt, argp);
142 va_end(argp);
143 }
144
145
146 /*
147 * setup shared memory area and get semaphore for locking
148 */
149 static void shm_init(void)
150 {
151 int fd;
152 caddr_t area;
153
154 if ((fd = open("/dev/zero", O_RDWR)) < 0) {
155 PARA_EMERG_LOG("%s", "failed to open /dev/zero\n");
156 exit(EXIT_FAILURE);
157 }
158 if ((area = mmap(0, sizeof(struct misc_meta_data),
159 PROT_READ | PROT_WRITE,
160 MAP_SHARED, fd, 0)) == (caddr_t) - 1) {
161 PARA_EMERG_LOG("%s", "mmap error\n");
162 exit(EXIT_FAILURE);
163 }
164 close(fd); /* we dont need /dev/zero anymore */
165 mmd = (struct misc_meta_data *)area;
166
167 mmd->dbt_num = 0;
168 mmd->num_played = 0;
169 mmd->num_commands = 0;
170 mmd->events = 0;
171 mmd->num_connects = 0;
172 mmd->active_connections = 0;
173 strcpy(mmd->filename, "(none)");
174 mmd->audio_format = -1;
175 mmd->afs_status_flags = AFS_NEXT;
176 mmd->new_afs_status_flags = AFS_NEXT;
177 mmd->sender_cmd_data.cmd_num = -1;
178
179 mmd_semid = semget(42, 1, IPC_CREAT | 0666);
180 if (mmd_semid == -1) {
181 PARA_EMERG_LOG("%s", "semget failed\n");
182 exit(EXIT_FAILURE);
183 }
184 }
185
186 static void do_semop(struct sembuf *sops, int num)
187 {
188 if (semop(mmd_semid, sops, num) >= 0)
189 return;
190 PARA_WARNING_LOG("semop failed (%s), retrying\n", strerror(errno));
191 while (semop(mmd_semid, sops, num) < 0)
192 ; /* nothing */
193 }
194
195 /**
196 * lock the shared memory area containing the mmd struct
197 *
198 * \sa semop(2), struct misc_meta_data
199 */
200 void mmd_lock(void)
201 {
202 struct sembuf sops[2] = {
203 {
204 .sem_num = 0,
205 .sem_op = 0,
206 .sem_flg = SEM_UNDO
207 },
208 {
209 .sem_num = 0,
210 .sem_op = 1,
211 .sem_flg = SEM_UNDO
212 }
213 };
214 do_semop(sops, 2);
215 }
216
217 /**
218 * unlock the shared memory area containing the mmd struct
219 *
220 * \sa semop(2), struct misc_meta_data
221 */
222 void mmd_unlock(void)
223 {
224 struct sembuf sops[1] = {
225 {
226 .sem_num = 0,
227 .sem_op = -1,
228 .sem_flg = SEM_UNDO
229 },
230 };
231 do_semop(sops, 1);
232 }
233
234 static void parse_config(int override)
235 {
236 char *home = para_homedir();
237 struct stat statbuf;
238 int ret;
239 char *cf;
240
241 if (conf.config_file_given)
242 cf = conf.config_file_arg;
243 else
244 cf = make_message("%s/.paraslash/server.conf", home);
245 free(user_list);
246 if (!conf.user_list_given)
247 user_list = make_message("%s/.paraslash/server.users", home);
248 else
249 user_list = para_strdup(conf.user_list_arg);
250 ret = stat(cf, &statbuf);
251 if (ret && conf.config_file_given) {
252 ret = -1;
253 PARA_EMERG_LOG("can not stat config file %s\n", cf);
254 goto out;
255 }
256 if (!ret) {
257 int tmp = conf.daemon_given;
258 cmdline_parser_configfile(cf, &conf, override, 0, 0);
259 conf.daemon_given = tmp;
260 }
261 /* logfile */
262 if (!conf.logfile_given && conf.daemon_given) {
263 ret = -1;
264 PARA_EMERG_LOG("%s", "daemon, but no log file\n");
265 goto out;
266 }
267 if (conf.logfile_given)
268 logfile = open_log(conf.logfile_arg);
269 ret = 1;
270 out:
271 free(cf);
272 free(home);
273 if (ret > 0)
274 return;
275 free(user_list);
276 user_list = NULL;
277 exit(EXIT_FAILURE);
278 }
279
280 static void setup_signal_handling(void)
281 {
282 int ret = 0;
283
284 signal_pipe = para_signal_init();
285 // fcntl(signal_pipe, F_SETFL, O_NONBLOCK);
286 PARA_NOTICE_LOG("%s", "setting up signal handlers\n");
287 ret += para_install_sighandler(SIGINT);
288 ret += para_install_sighandler(SIGTERM);
289 ret += para_install_sighandler(SIGHUP);
290 ret += para_install_sighandler(SIGCHLD);
291 signal(SIGPIPE, SIG_IGN);
292 signal(SIGUSR1, SIG_IGN);
293 if (ret != 4) {
294 PARA_EMERG_LOG("%s", "could not install signal handlers\n");
295 exit(EXIT_FAILURE);
296 }
297 }
298
299 static void init_dbtool(void)
300 {
301 int i;
302
303 mmd->dbt_change = -1; /* no change nec., set to new dbt num by com_cdt */
304 if (!dblist[1].name)
305 goto dopey;
306 if (conf.dbtool_given) {
307 for (i = 0; dblist[i].name; i++) {
308 if (strcmp(dblist[i].name, conf.dbtool_arg))
309 continue;
310 PARA_NOTICE_LOG("initializing %s database tool\n",
311 dblist[i].name);
312 if (dblist[i].init(&dblist[i]) < 0) {
313 PARA_WARNING_LOG("init %s failed",
314 dblist[i].name);
315 goto dopey;
316 }
317 mmd->dbt_num = i;
318 return;
319 }
320 PARA_WARNING_LOG("%s", "no such dbtool, switching to dopey\n");
321 goto dopey;
322 }
323 /* use the first dbtool that works
324 * (assuming that dopey always works)
325 */
326 for (i = 1; dblist[i].name; i++) {
327 int ret = dblist[i].init(&dblist[i]);
328 if (ret >= 0) {
329 PARA_INFO_LOG("initialized %s\n", dblist[i].name);
330 mmd->dbt_num = i;
331 return;
332 }
333 PARA_CRIT_LOG("%s init failed: %s\n", dblist[i].name,
334 PARA_STRERROR(-ret));
335 }
336 dopey:
337 mmd->dbt_num = 0;
338 dblist[0].init(&dblist[0]); /* always successful */
339 }
340
341 static unsigned init_network(void)
342 {
343 int sockfd = init_tcp_socket(conf.port_arg);
344
345 if (sockfd < 0)
346 exit(EXIT_FAILURE);
347 return sockfd;
348 }
349
350 static void init_random_seed(void)
351 {
352 int fd, ret = -1, len = sizeof(unsigned int);
353 unsigned int seed;
354
355 fd = open("/dev/random", O_RDONLY);
356 if (fd < 0)
357 goto out;
358 ret = -2;
359 if (read(fd, &seed, len) != len)
360 goto out;
361 srandom(seed);
362 ret = 1;
363 out:
364 if (fd >= 0)
365 close(fd);
366 if (ret > 0)
367 return;
368 PARA_EMERG_LOG("can not seed pseudo random generator (ret = %d)\n",
369 ret);
370 exit(EXIT_FAILURE);
371 }
372
373 static unsigned do_inits(int argc, char **argv)
374 {
375 /* connector's address information */
376 int sockfd;
377
378 init_random_seed();
379 /* parse command line options */
380 cmdline_parser(argc, argv, &conf);
381 para_drop_privileges(conf.user_arg);
382 /* parse config file, open log and set defaults */
383 parse_config(0);
384 log_welcome("para_server", conf.loglevel_arg);
385 shm_init(); /* init mmd struct */
386 server_uptime(UPTIME_SET); /* reset server uptime */
387 /* become daemon */
388 if (conf.daemon_given)
389 daemon_init();
390 init_dbtool();
391 PARA_NOTICE_LOG("%s", "initializing audio file sender\n");
392 /* audio file sender */
393 afs_init();
394 mmd->server_pid = getpid();
395 setup_signal_handling();
396 mmd_lock();
397 /* init network socket */
398 PARA_NOTICE_LOG("%s", "initializing tcp command socket\n");
399 sockfd = init_network();
400 if (conf.autoplay_given) {
401 mmd->afs_status_flags |= AFS_PLAYING;
402 mmd->new_afs_status_flags |= AFS_PLAYING;
403 }
404 PARA_NOTICE_LOG("%s", "init complete\n");
405 return sockfd;
406 }
407
408 static void handle_dbt_change(void)
409 {
410 int ret, old = mmd->dbt_num, new = mmd->dbt_change;
411
412 dblist[old].shutdown();
413 ret = dblist[new].init(&dblist[new]);
414 mmd->dbt_change = -1; /* reset */
415 if (ret >= 0) {
416 mmd->dbt_num = new;
417 return;
418 }
419 /* init failed */
420 PARA_ERROR_LOG("%s -- switching to dopey\n", PARA_STRERROR(-ret));
421 dblist[0].init(&dblist[0]);
422 mmd->dbt_num = 0;
423 }
424
425 /*
426 * called when server gets SIGHUP or when client invokes hup command.
427 */
428 static void handle_sighup(void)
429 {
430 PARA_NOTICE_LOG("%s", "SIGHUP\n");
431 close_log(logfile); /* gets reopened if necessary by parse_config */
432 logfile = NULL;
433 parse_config(1); /* reopens log */
434 mmd->dbt_change = mmd->dbt_num; /* do not change dbtool */
435 handle_dbt_change(); /* force reloading dbtool */
436 }
437
438 static void status_refresh(void)
439 {
440 static int prev_uptime = -1, prev_events = -1;
441 int uptime = server_uptime(UPTIME_GET), ret = 1;
442
443 if (prev_events != mmd->events)
444 goto out;
445 if (mmd->new_afs_status_flags != mmd->afs_status_flags)
446 goto out;
447 if (uptime / 60 != prev_uptime / 60)
448 goto out;
449 ret = 0;
450 out:
451 prev_uptime = uptime;
452 prev_events = mmd->events;
453 mmd->afs_status_flags = mmd->new_afs_status_flags;
454 if (ret) {
455 PARA_DEBUG_LOG("%d events, forcing status update, af = %d\n",
456 mmd->events, mmd->audio_format);
457 killpg(0, SIGUSR1);
458 }
459 }
460
461 /*
462 * MAIN
463 */
464 int main(int argc, char *argv[])
465 {
466 /* listen on sock_fd, new connection on new_fd */
467 int sockfd, new_fd;
468 struct sockaddr_in their_addr;
469 int err, i, max_fileno, ret;
470 pid_t chld_pid;
471 fd_set rfds, wfds;
472 struct timeval *timeout;
473
474 valid_fd_012();
475 sockfd = do_inits(argc, argv);
476 repeat:
477 /* check socket and signal pipe in any case */
478 FD_ZERO(&rfds);
479 FD_ZERO(&wfds);
480 FD_SET(sockfd, &rfds);
481 max_fileno = sockfd;
482 FD_SET(signal_pipe, &rfds);
483 max_fileno = MAX(max_fileno, signal_pipe);
484
485 timeout = afs_preselect();
486 status_refresh();
487 for (i = 0; senders[i].name; i++) {
488 if (senders[i].status != SENDER_ON)
489 continue;
490 if (!senders[i].pre_select)
491 continue;
492 senders[i].pre_select(mmd->audio_format >= 0?
493 &afl[mmd->audio_format] : NULL,
494 &max_fileno,
495 &rfds, &wfds);
496 }
497 mmd_unlock();
498 // PARA_DEBUG_LOG("%s: select (max = %i)\n", __func__, max_fileno);
499 ret = select(max_fileno + 1, &rfds, &wfds, NULL, timeout);
500 err = errno;
501 //PARA_DEBUG_LOG("%s: select returned %i\n", __func__, ret);
502 mmd_lock();
503 if (mmd->dbt_change >= 0)
504 handle_dbt_change();
505 if (ret < 0 && err == EINTR)
506 goto repeat;
507 if (ret < 0) {
508 PARA_CRIT_LOG("select error (%s)\n", strerror(err));
509 goto repeat;
510 }
511 for (i = 0; senders[i].name; i++) {
512 if (senders[i].status != SENDER_ON)
513 continue;
514 if (!senders[i].post_select)
515 continue;
516 senders[i].post_select(mmd->audio_format >= 0?
517 &afl[mmd->audio_format] : NULL,
518 &rfds, &wfds);
519 }
520 if (!ret) {
521 afs_send_chunk();
522 status_refresh();
523 }
524 if (FD_ISSET(signal_pipe, &rfds)) {
525 int sig;
526 sig = para_next_signal();
527 switch (sig) {
528 case SIGHUP:
529 handle_sighup();
530 break;
531 case SIGCHLD:
532 para_reap_children();
533 break;
534 /* die on sigint/sigterm. Kill all children too. */
535 case SIGINT:
536 case SIGTERM:
537 PARA_EMERG_LOG("terminating on signal %d\n", sig);
538 kill(0, SIGTERM);
539 exit(EXIT_FAILURE);
540 }
541 }
542 if (mmd->sender_cmd_data.cmd_num >= 0) {
543 int num = mmd->sender_cmd_data.cmd_num,
544 s = mmd->sender_cmd_data.sender_num;
545
546 if (senders[s].client_cmds[num])
547 senders[s].client_cmds[num](&mmd->sender_cmd_data);
548 mmd->sender_cmd_data.cmd_num = -1;
549 }
550 if (!FD_ISSET(sockfd, &rfds))
551 goto repeat;
552
553 new_fd = para_accept(sockfd, &their_addr, sizeof(struct sockaddr_in));
554 if (new_fd < 0)
555 goto repeat;
556 PARA_INFO_LOG("got connection from %s, forking\n",
557 inet_ntoa(their_addr.sin_addr));
558 mmd->num_connects++;
559 mmd->active_connections++;
560 random();
561 chld_pid = fork();
562 if (chld_pid < 0) {
563 PARA_CRIT_LOG("%s", "fork failed\n");
564 goto repeat;
565 }
566 if (chld_pid) {
567 close(new_fd);
568 /* parent keeps accepting connections */
569 goto repeat;
570 }
571 alarm(ALARM_TIMEOUT);
572 close_listed_fds();
573 close(sockfd); /* child doesn't need the listener */
574 /*
575 * put info on who we are serving into argv[0] to make
576 * client ip visible in top/ps
577 */
578 for (i = argc - 1; i >= 0; i--)
579 memset(argv[i], 0, strlen(argv[i]));
580 sprintf(argv[0], "para_server (serving %s)",
581 inet_ntoa(their_addr.sin_addr));
582 return handle_connect(new_fd, &their_addr);
583 }